1 2=head1 NAME 3 4perl5db.pl - the perl debugger 5 6=head1 SYNOPSIS 7 8 perl -d your_Perl_script 9 10=head1 DESCRIPTION 11 12C<perl5db.pl> is the perl debugger. It is loaded automatically by Perl when 13you invoke a script with C<perl -d>. This documentation tries to outline the 14structure and services provided by C<perl5db.pl>, and to describe how you 15can use them. 16 17=head1 GENERAL NOTES 18 19The debugger can look pretty forbidding to many Perl programmers. There are 20a number of reasons for this, many stemming out of the debugger's history. 21 22When the debugger was first written, Perl didn't have a lot of its nicer 23features - no references, no lexical variables, no closures, no object-oriented 24programming. So a lot of the things one would normally have done using such 25features was done using global variables, globs and the C<local()> operator 26in creative ways. 27 28Some of these have survived into the current debugger; a few of the more 29interesting and still-useful idioms are noted in this section, along with notes 30on the comments themselves. 31 32=head2 Why not use more lexicals? 33 34Experienced Perl programmers will note that the debugger code tends to use 35mostly package globals rather than lexically-scoped variables. This is done 36to allow a significant amount of control of the debugger from outside the 37debugger itself. 38 39Unfortunately, though the variables are accessible, they're not well 40documented, so it's generally been a decision that hasn't made a lot of 41difference to most users. Where appropriate, comments have been added to 42make variables more accessible and usable, with the understanding that these 43I<are> debugger internals, and are therefore subject to change. Future 44development should probably attempt to replace the globals with a well-defined 45API, but for now, the variables are what we've got. 46 47=head2 Automated variable stacking via C<local()> 48 49As you may recall from reading C<perlfunc>, the C<local()> operator makes a 50temporary copy of a variable in the current scope. When the scope ends, the 51old copy is restored. This is often used in the debugger to handle the 52automatic stacking of variables during recursive calls: 53 54 sub foo { 55 local $some_global++; 56 57 # Do some stuff, then ... 58 return; 59 } 60 61What happens is that on entry to the subroutine, C<$some_global> is localized, 62then altered. When the subroutine returns, Perl automatically undoes the 63localization, restoring the previous value. Voila, automatic stack management. 64 65The debugger uses this trick a I<lot>. Of particular note is C<DB::eval>, 66which lets the debugger get control inside of C<eval>'ed code. The debugger 67localizes a saved copy of C<$@> inside the subroutine, which allows it to 68keep C<$@> safe until it C<DB::eval> returns, at which point the previous 69value of C<$@> is restored. This makes it simple (well, I<simpler>) to keep 70track of C<$@> inside C<eval>s which C<eval> other C<eval's>. 71 72In any case, watch for this pattern. It occurs fairly often. 73 74=head2 The C<^> trick 75 76This is used to cleverly reverse the sense of a logical test depending on 77the value of an auxiliary variable. For instance, the debugger's C<S> 78(search for subroutines by pattern) allows you to negate the pattern 79like this: 80 81 # Find all non-'foo' subs: 82 S !/foo/ 83 84Boolean algebra states that the truth table for XOR looks like this: 85 86=over 4 87 88=item * 0 ^ 0 = 0 89 90(! not present and no match) --> false, don't print 91 92=item * 0 ^ 1 = 1 93 94(! not present and matches) --> true, print 95 96=item * 1 ^ 0 = 1 97 98(! present and no match) --> true, print 99 100=item * 1 ^ 1 = 0 101 102(! present and matches) --> false, don't print 103 104=back 105 106As you can see, the first pair applies when C<!> isn't supplied, and 107the second pair applies when it is. The XOR simply allows us to 108compact a more complicated if-then-elseif-else into a more elegant 109(but perhaps overly clever) single test. After all, it needed this 110explanation... 111 112=head2 FLAGS, FLAGS, FLAGS 113 114There is a certain C programming legacy in the debugger. Some variables, 115such as C<$single>, C<$trace>, and C<$frame>, have I<magical> values composed 116of 1, 2, 4, etc. (powers of 2) OR'ed together. This allows several pieces 117of state to be stored independently in a single scalar. 118 119A test like 120 121 if ($scalar & 4) ... 122 123is checking to see if the appropriate bit is on. Since each bit can be 124"addressed" independently in this way, C<$scalar> is acting sort of like 125an array of bits. Obviously, since the contents of C<$scalar> are just a 126bit-pattern, we can save and restore it easily (it will just look like 127a number). 128 129The problem, is of course, that this tends to leave magic numbers scattered 130all over your program whenever a bit is set, cleared, or checked. So why do 131it? 132 133=over 4 134 135=item * 136 137First, doing an arithmetical or bitwise operation on a scalar is 138just about the fastest thing you can do in Perl: C<use constant> actually 139creates a subroutine call, and array and hash lookups are much slower. Is 140this over-optimization at the expense of readability? Possibly, but the 141debugger accesses these variables a I<lot>. Any rewrite of the code will 142probably have to benchmark alternate implementations and see which is the 143best balance of readability and speed, and then document how it actually 144works. 145 146=item * 147 148Second, it's very easy to serialize a scalar number. This is done in 149the restart code; the debugger state variables are saved in C<%ENV> and then 150restored when the debugger is restarted. Having them be just numbers makes 151this trivial. 152 153=item * 154 155Third, some of these variables are being shared with the Perl core 156smack in the middle of the interpreter's execution loop. It's much faster for 157a C program (like the interpreter) to check a bit in a scalar than to access 158several different variables (or a Perl array). 159 160=back 161 162=head2 What are those C<XXX> comments for? 163 164Any comment containing C<XXX> means that the comment is either somewhat 165speculative - it's not exactly clear what a given variable or chunk of 166code is doing, or that it is incomplete - the basics may be clear, but the 167subtleties are not completely documented. 168 169Send in a patch if you can clear up, fill out, or clarify an C<XXX>. 170 171=head1 DATA STRUCTURES MAINTAINED BY CORE 172 173There are a number of special data structures provided to the debugger by 174the Perl interpreter. 175 176The array C<@{$main::{'_<'.$filename}}> (aliased locally to C<@dbline> 177via glob assignment) contains the text from C<$filename>, with each 178element corresponding to a single line of C<$filename>. Additionally, 179breakable lines will be dualvars with the numeric component being the 180memory address of a COP node. Non-breakable lines are dualvar to 0. 181 182The hash C<%{'_<'.$filename}> (aliased locally to C<%dbline> via glob 183assignment) contains breakpoints and actions. The keys are line numbers; 184you can set individual values, but not the whole hash. The Perl interpreter 185uses this hash to determine where breakpoints have been set. Any true value is 186considered to be a breakpoint; C<perl5db.pl> uses C<$break_condition\0$action>. 187Values are magical in numeric context: 1 if the line is breakable, 0 if not. 188 189The scalar C<${"_<$filename"}> simply contains the string C<$filename>. 190This is also the case for evaluated strings that contain subroutines, or 191which are currently being executed. The $filename for C<eval>ed strings looks 192like C<(eval 34). 193 194=head1 DEBUGGER STARTUP 195 196When C<perl5db.pl> starts, it reads an rcfile (C<perl5db.ini> for 197non-interactive sessions, C<.perldb> for interactive ones) that can set a number 198of options. In addition, this file may define a subroutine C<&afterinit> 199that will be executed (in the debugger's context) after the debugger has 200initialized itself. 201 202Next, it checks the C<PERLDB_OPTS> environment variable and treats its 203contents as the argument of a C<o> command in the debugger. 204 205=head2 STARTUP-ONLY OPTIONS 206 207The following options can only be specified at startup. 208To set them in your rcfile, add a call to 209C<&parse_options("optionName=new_value")>. 210 211=over 4 212 213=item * TTY 214 215the TTY to use for debugging i/o. 216 217=item * noTTY 218 219if set, goes in NonStop mode. On interrupt, if TTY is not set, 220uses the value of noTTY or F<$HOME/.perldbtty$$> to find TTY using 221Term::Rendezvous. Current variant is to have the name of TTY in this 222file. 223 224=item * ReadLine 225 226if false, a dummy ReadLine is used, so you can debug 227ReadLine applications. 228 229=item * NonStop 230 231if true, no i/o is performed until interrupt. 232 233=item * LineInfo 234 235file or pipe to print line number info to. If it is a 236pipe, a short "emacs like" message is used. 237 238=item * RemotePort 239 240host:port to connect to on remote host for remote debugging. 241 242=item * HistFile 243 244file to store session history to. There is no default and so no 245history file is written unless this variable is explicitly set. 246 247=item * HistSize 248 249number of commands to store to the file specified in C<HistFile>. 250Default is 100. 251 252=back 253 254=head3 SAMPLE RCFILE 255 256 &parse_options("NonStop=1 LineInfo=db.out"); 257 sub afterinit { $trace = 1; } 258 259The script will run without human intervention, putting trace 260information into C<db.out>. (If you interrupt it, you had better 261reset C<LineInfo> to something I<interactive>!) 262 263=head1 INTERNALS DESCRIPTION 264 265=head2 DEBUGGER INTERFACE VARIABLES 266 267Perl supplies the values for C<%sub>. It effectively inserts 268a C<&DB::DB();> in front of each place that can have a 269breakpoint. At each subroutine call, it calls C<&DB::sub> with 270C<$DB::sub> set to the called subroutine. It also inserts a C<BEGIN 271{require 'perl5db.pl'}> before the first line. 272 273After each C<require>d file is compiled, but before it is executed, a 274call to C<&DB::postponed($main::{'_<'.$filename})> is done. C<$filename> 275is the expanded name of the C<require>d file (as found via C<%INC>). 276 277=head3 IMPORTANT INTERNAL VARIABLES 278 279=head4 C<$CreateTTY> 280 281Used to control when the debugger will attempt to acquire another TTY to be 282used for input. 283 284=over 285 286=item * 1 - on C<fork()> 287 288=item * 2 - debugger is started inside debugger 289 290=item * 4 - on startup 291 292=back 293 294=head4 C<$doret> 295 296The value -2 indicates that no return value should be printed. 297Any other positive value causes C<DB::sub> to print return values. 298 299=head4 C<$evalarg> 300 301The item to be eval'ed by C<DB::eval>. Used to prevent messing with the current 302contents of C<@_> when C<DB::eval> is called. 303 304=head4 C<$frame> 305 306Determines what messages (if any) will get printed when a subroutine (or eval) 307is entered or exited. 308 309=over 4 310 311=item * 0 - No enter/exit messages 312 313=item * 1 - Print I<entering> messages on subroutine entry 314 315=item * 2 - Adds exit messages on subroutine exit. If no other flag is on, acts like 1+2. 316 317=item * 4 - Extended messages: C<< <in|out> I<context>=I<fully-qualified sub name> from I<file>:I<line> >>. If no other flag is on, acts like 1+4. 318 319=item * 8 - Adds parameter information to messages, and overloaded stringify and tied FETCH is enabled on the printed arguments. Ignored if C<4> is not on. 320 321=item * 16 - Adds C<I<context> return from I<subname>: I<value>> messages on subroutine/eval exit. Ignored if C<4> is is not on. 322 323=back 324 325To get everything, use C<$frame=30> (or C<o f=30> as a debugger command). 326The debugger internally juggles the value of C<$frame> during execution to 327protect external modules that the debugger uses from getting traced. 328 329=head4 C<$level> 330 331Tracks current debugger nesting level. Used to figure out how many 332C<E<lt>E<gt>> pairs to surround the line number with when the debugger 333outputs a prompt. Also used to help determine if the program has finished 334during command parsing. 335 336=head4 C<$onetimeDump> 337 338Controls what (if anything) C<DB::eval()> will print after evaluating an 339expression. 340 341=over 4 342 343=item * C<undef> - don't print anything 344 345=item * C<dump> - use C<dumpvar.pl> to display the value returned 346 347=item * C<methods> - print the methods callable on the first item returned 348 349=back 350 351=head4 C<$onetimeDumpDepth> 352 353Controls how far down C<dumpvar.pl> will go before printing C<...> while 354dumping a structure. Numeric. If C<undef>, print all levels. 355 356=head4 C<$signal> 357 358Used to track whether or not an C<INT> signal has been detected. C<DB::DB()>, 359which is called before every statement, checks this and puts the user into 360command mode if it finds C<$signal> set to a true value. 361 362=head4 C<$single> 363 364Controls behavior during single-stepping. Stacked in C<@stack> on entry to 365each subroutine; popped again at the end of each subroutine. 366 367=over 4 368 369=item * 0 - run continuously. 370 371=item * 1 - single-step, go into subs. The C<s> command. 372 373=item * 2 - single-step, don't go into subs. The C<n> command. 374 375=item * 4 - print current sub depth (turned on to force this when C<too much 376recursion> occurs. 377 378=back 379 380=head4 C<$trace> 381 382Controls the output of trace information. 383 384=over 4 385 386=item * 1 - The C<t> command was entered to turn on tracing (every line executed is printed) 387 388=item * 2 - watch expressions are active 389 390=item * 4 - user defined a C<watchfunction()> in C<afterinit()> 391 392=back 393 394=head4 C<$slave_editor> 395 3961 if C<LINEINFO> was directed to a pipe; 0 otherwise. 397 398=head4 C<@cmdfhs> 399 400Stack of filehandles that C<DB::readline()> will read commands from. 401Manipulated by the debugger's C<source> command and C<DB::readline()> itself. 402 403=head4 C<@dbline> 404 405Local alias to the magical line array, C<@{$main::{'_<'.$filename}}> , 406supplied by the Perl interpreter to the debugger. Contains the source. 407 408=head4 C<@old_watch> 409 410Previous values of watch expressions. First set when the expression is 411entered; reset whenever the watch expression changes. 412 413=head4 C<@saved> 414 415Saves important globals (C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, C<$\>, C<$^W>) 416so that the debugger can substitute safe values while it's running, and 417restore them when it returns control. 418 419=head4 C<@stack> 420 421Saves the current value of C<$single> on entry to a subroutine. 422Manipulated by the C<c> command to turn off tracing in all subs above the 423current one. 424 425=head4 C<@to_watch> 426 427The 'watch' expressions: to be evaluated before each line is executed. 428 429=head4 C<@typeahead> 430 431The typeahead buffer, used by C<DB::readline>. 432 433=head4 C<%alias> 434 435Command aliases. Stored as character strings to be substituted for a command 436entered. 437 438=head4 C<%break_on_load> 439 440Keys are file names, values are 1 (break when this file is loaded) or undef 441(don't break when it is loaded). 442 443=head4 C<%dbline> 444 445Keys are line numbers, values are C<condition\0action>. If used in numeric 446context, values are 0 if not breakable, 1 if breakable, no matter what is 447in the actual hash entry. 448 449=head4 C<%had_breakpoints> 450 451Keys are file names; values are bitfields: 452 453=over 4 454 455=item * 1 - file has a breakpoint in it. 456 457=item * 2 - file has an action in it. 458 459=back 460 461A zero or undefined value means this file has neither. 462 463=head4 C<%option> 464 465Stores the debugger options. These are character string values. 466 467=head4 C<%postponed> 468 469Saves breakpoints for code that hasn't been compiled yet. 470Keys are subroutine names, values are: 471 472=over 4 473 474=item * C<compile> - break when this sub is compiled 475 476=item * C<< break +0 if <condition> >> - break (conditionally) at the start of this routine. The condition will be '1' if no condition was specified. 477 478=back 479 480=head4 C<%postponed_file> 481 482This hash keeps track of breakpoints that need to be set for files that have 483not yet been compiled. Keys are filenames; values are references to hashes. 484Each of these hashes is keyed by line number, and its values are breakpoint 485definitions (C<condition\0action>). 486 487=head1 DEBUGGER INITIALIZATION 488 489The debugger's initialization actually jumps all over the place inside this 490package. This is because there are several BEGIN blocks (which of course 491execute immediately) spread through the code. Why is that? 492 493The debugger needs to be able to change some things and set some things up 494before the debugger code is compiled; most notably, the C<$deep> variable that 495C<DB::sub> uses to tell when a program has recursed deeply. In addition, the 496debugger has to turn off warnings while the debugger code is compiled, but then 497restore them to their original setting before the program being debugged begins 498executing. 499 500The first C<BEGIN> block simply turns off warnings by saving the current 501setting of C<$^W> and then setting it to zero. The second one initializes 502the debugger variables that are needed before the debugger begins executing. 503The third one puts C<$^X> back to its former value. 504 505We'll detail the second C<BEGIN> block later; just remember that if you need 506to initialize something before the debugger starts really executing, that's 507where it has to go. 508 509=cut 510 511package DB; 512 513use strict; 514 515BEGIN {eval 'use IO::Handle'}; # Needed for flush only? breaks under miniperl 516 517BEGIN { 518 require feature; 519 $^V =~ /^v(\d+\.\d+)/; 520 feature->import(":$1"); 521} 522 523# Debugger for Perl 5.00x; perl5db.pl patch level: 524use vars qw($VERSION $header); 525 526$VERSION = '1.39_10'; 527 528$header = "perl5db.pl version $VERSION"; 529 530=head1 DEBUGGER ROUTINES 531 532=head2 C<DB::eval()> 533 534This function replaces straight C<eval()> inside the debugger; it simplifies 535the process of evaluating code in the user's context. 536 537The code to be evaluated is passed via the package global variable 538C<$DB::evalarg>; this is done to avoid fiddling with the contents of C<@_>. 539 540Before we do the C<eval()>, we preserve the current settings of C<$trace>, 541C<$single>, C<$^D> and C<$usercontext>. The latter contains the 542preserved values of C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, C<$\>, C<$^W> and the 543user's current package, grabbed when C<DB::DB> got control. This causes the 544proper context to be used when the eval is actually done. Afterward, we 545restore C<$trace>, C<$single>, and C<$^D>. 546 547Next we need to handle C<$@> without getting confused. We save C<$@> in a 548local lexical, localize C<$saved[0]> (which is where C<save()> will put 549C<$@>), and then call C<save()> to capture C<$@>, C<$!>, C<$^E>, C<$,>, 550C<$/>, C<$\>, and C<$^W>) and set C<$,>, C<$/>, C<$\>, and C<$^W> to values 551considered sane by the debugger. If there was an C<eval()> error, we print 552it on the debugger's output. If C<$onetimedump> is defined, we call 553C<dumpit> if it's set to 'dump', or C<methods> if it's set to 554'methods'. Setting it to something else causes the debugger to do the eval 555but not print the result - handy if you want to do something else with it 556(the "watch expressions" code does this to get the value of the watch 557expression but not show it unless it matters). 558 559In any case, we then return the list of output from C<eval> to the caller, 560and unwinding restores the former version of C<$@> in C<@saved> as well 561(the localization of C<$saved[0]> goes away at the end of this scope). 562 563=head3 Parameters and variables influencing execution of DB::eval() 564 565C<DB::eval> isn't parameterized in the standard way; this is to keep the 566debugger's calls to C<DB::eval()> from mucking with C<@_>, among other things. 567The variables listed below influence C<DB::eval()>'s execution directly. 568 569=over 4 570 571=item C<$evalarg> - the thing to actually be eval'ed 572 573=item C<$trace> - Current state of execution tracing 574 575=item C<$single> - Current state of single-stepping 576 577=item C<$onetimeDump> - what is to be displayed after the evaluation 578 579=item C<$onetimeDumpDepth> - how deep C<dumpit()> should go when dumping results 580 581=back 582 583The following variables are altered by C<DB::eval()> during its execution. They 584are "stacked" via C<local()>, enabling recursive calls to C<DB::eval()>. 585 586=over 4 587 588=item C<@res> - used to capture output from actual C<eval>. 589 590=item C<$otrace> - saved value of C<$trace>. 591 592=item C<$osingle> - saved value of C<$single>. 593 594=item C<$od> - saved value of C<$^D>. 595 596=item C<$saved[0]> - saved value of C<$@>. 597 598=item $\ - for output of C<$@> if there is an evaluation error. 599 600=back 601 602=head3 The problem of lexicals 603 604The context of C<DB::eval()> presents us with some problems. Obviously, 605we want to be 'sandboxed' away from the debugger's internals when we do 606the eval, but we need some way to control how punctuation variables and 607debugger globals are used. 608 609We can't use local, because the code inside C<DB::eval> can see localized 610variables; and we can't use C<my> either for the same reason. The code 611in this routine compromises and uses C<my>. 612 613After this routine is over, we don't have user code executing in the debugger's 614context, so we can use C<my> freely. 615 616=cut 617 618############################################## Begin lexical danger zone 619 620# 'my' variables used here could leak into (that is, be visible in) 621# the context that the code being evaluated is executing in. This means that 622# the code could modify the debugger's variables. 623# 624# Fiddling with the debugger's context could be Bad. We insulate things as 625# much as we can. 626 627use vars qw( 628 @args 629 %break_on_load 630 $CommandSet 631 $CreateTTY 632 $DBGR 633 @dbline 634 $dbline 635 %dbline 636 $dieLevel 637 $filename 638 $histfile 639 $histsize 640 $IN 641 $inhibit_exit 642 @ini_INC 643 $ini_warn 644 $maxtrace 645 $od 646 @options 647 $osingle 648 $otrace 649 $pager 650 $post 651 %postponed 652 $prc 653 $pre 654 $pretype 655 $psh 656 @RememberOnROptions 657 $remoteport 658 @res 659 $rl 660 @saved 661 $signalLevel 662 $sub 663 $term 664 $usercontext 665 $warnLevel 666); 667 668our ( 669 @cmdfhs, 670 $evalarg, 671 $frame, 672 $hist, 673 $ImmediateStop, 674 $line, 675 $onetimeDump, 676 $onetimedumpDepth, 677 %option, 678 $OUT, 679 $packname, 680 $signal, 681 $single, 682 $start, 683 %sub, 684 $subname, 685 $trace, 686 $window, 687); 688 689# Used to save @ARGV and extract any debugger-related flags. 690use vars qw(@ARGS); 691 692# Used to prevent multiple entries to diesignal() 693# (if for instance diesignal() itself dies) 694use vars qw($panic); 695 696# Used to prevent the debugger from running nonstop 697# after a restart 698our ($second_time); 699 700sub _calc_usercontext { 701 my ($package) = @_; 702 703 # Cancel strict completely for the evaluated code, so the code 704 # the user evaluates won't be affected by it. (Shlomi Fish) 705 return 'no strict; ($@, $!, $^E, $,, $/, $\, $^W) = @DB::saved;' 706 . "package $package;"; # this won't let them modify, alas 707} 708 709sub eval { 710 711 # 'my' would make it visible from user code 712 # but so does local! --tchrist 713 # Remember: this localizes @DB::res, not @main::res. 714 local @res; 715 { 716 717 # Try to keep the user code from messing with us. Save these so that 718 # even if the eval'ed code changes them, we can put them back again. 719 # Needed because the user could refer directly to the debugger's 720 # package globals (and any 'my' variables in this containing scope) 721 # inside the eval(), and we want to try to stay safe. 722 local $otrace = $trace; 723 local $osingle = $single; 724 local $od = $^D; 725 726 # Untaint the incoming eval() argument. 727 { ($evalarg) = $evalarg =~ /(.*)/s; } 728 729 # $usercontext built in DB::DB near the comment 730 # "set up the context for DB::eval ..." 731 # Evaluate and save any results. 732 @res = eval "$usercontext $evalarg;\n"; # '\n' for nice recursive debug 733 734 # Restore those old values. 735 $trace = $otrace; 736 $single = $osingle; 737 $^D = $od; 738 } 739 740 # Save the current value of $@, and preserve it in the debugger's copy 741 # of the saved precious globals. 742 my $at = $@; 743 744 # Since we're only saving $@, we only have to localize the array element 745 # that it will be stored in. 746 local $saved[0]; # Preserve the old value of $@ 747 eval { &DB::save }; 748 749 # Now see whether we need to report an error back to the user. 750 if ($at) { 751 local $\ = ''; 752 print $OUT $at; 753 } 754 755 # Display as required by the caller. $onetimeDump and $onetimedumpDepth 756 # are package globals. 757 elsif ($onetimeDump) { 758 if ( $onetimeDump eq 'dump' ) { 759 local $option{dumpDepth} = $onetimedumpDepth 760 if defined $onetimedumpDepth; 761 dumpit( $OUT, \@res ); 762 } 763 elsif ( $onetimeDump eq 'methods' ) { 764 methods( $res[0] ); 765 } 766 } ## end elsif ($onetimeDump) 767 @res; 768} ## end sub eval 769 770############################################## End lexical danger zone 771 772# After this point it is safe to introduce lexicals. 773# The code being debugged will be executing in its own context, and 774# can't see the inside of the debugger. 775# 776# However, one should not overdo it: leave as much control from outside as 777# possible. If you make something a lexical, it's not going to be addressable 778# from outside the debugger even if you know its name. 779 780# This file is automatically included if you do perl -d. 781# It's probably not useful to include this yourself. 782# 783# Before venturing further into these twisty passages, it is 784# wise to read the perldebguts man page or risk the ire of dragons. 785# 786# (It should be noted that perldebguts will tell you a lot about 787# the underlying mechanics of how the debugger interfaces into the 788# Perl interpreter, but not a lot about the debugger itself. The new 789# comments in this code try to address this problem.) 790 791# Note that no subroutine call is possible until &DB::sub is defined 792# (for subroutines defined outside of the package DB). In fact the same is 793# true if $deep is not defined. 794 795# Enhanced by ilya@math.ohio-state.edu (Ilya Zakharevich) 796 797# modified Perl debugger, to be run from Emacs in perldb-mode 798# Ray Lischner (uunet!mntgfx!lisch) as of 5 Nov 1990 799# Johan Vromans -- upgrade to 4.0 pl 10 800# Ilya Zakharevich -- patches after 5.001 (and some before ;-) 801######################################################################## 802 803=head1 DEBUGGER INITIALIZATION 804 805The debugger starts up in phases. 806 807=head2 BASIC SETUP 808 809First, it initializes the environment it wants to run in: turning off 810warnings during its own compilation, defining variables which it will need 811to avoid warnings later, setting itself up to not exit when the program 812terminates, and defaulting to printing return values for the C<r> command. 813 814=cut 815 816# Needed for the statement after exec(): 817# 818# This BEGIN block is simply used to switch off warnings during debugger 819# compilation. Probably it would be better practice to fix the warnings, 820# but this is how it's done at the moment. 821 822BEGIN { 823 $ini_warn = $^W; 824 $^W = 0; 825} # Switch compilation warnings off until another BEGIN. 826 827local ($^W) = 0; # Switch run-time warnings off during init. 828 829=head2 THREADS SUPPORT 830 831If we are running under a threaded Perl, we require threads and threads::shared 832if the environment variable C<PERL5DB_THREADED> is set, to enable proper 833threaded debugger control. C<-dt> can also be used to set this. 834 835Each new thread will be announced and the debugger prompt will always inform 836you of each new thread created. It will also indicate the thread id in which 837we are currently running within the prompt like this: 838 839 [tid] DB<$i> 840 841Where C<[tid]> is an integer thread id and C<$i> is the familiar debugger 842command prompt. The prompt will show: C<[0]> when running under threads, but 843not actually in a thread. C<[tid]> is consistent with C<gdb> usage. 844 845While running under threads, when you set or delete a breakpoint (etc.), this 846will apply to all threads, not just the currently running one. When you are 847in a currently executing thread, you will stay there until it completes. With 848the current implementation it is not currently possible to hop from one thread 849to another. 850 851The C<e> and C<E> commands are currently fairly minimal - see C<h e> and C<h E>. 852 853Note that threading support was built into the debugger as of Perl version 854C<5.8.6> and debugger version C<1.2.8>. 855 856=cut 857 858BEGIN { 859 # ensure we can share our non-threaded variables or no-op 860 if ($ENV{PERL5DB_THREADED}) { 861 require threads; 862 require threads::shared; 863 import threads::shared qw(share); 864 $DBGR; 865 share(\$DBGR); 866 lock($DBGR); 867 print "Threads support enabled\n"; 868 } else { 869 *share = sub(\[$@%]) {}; 870 } 871} 872 873# These variables control the execution of 'dumpvar.pl'. 874{ 875 package dumpvar; 876 use vars qw( 877 $hashDepth 878 $arrayDepth 879 $dumpDBFiles 880 $dumpPackages 881 $quoteHighBit 882 $printUndef 883 $globPrint 884 $usageOnly 885 ); 886} 887 888# used to control die() reporting in diesignal() 889{ 890 package Carp; 891 use vars qw($CarpLevel); 892} 893 894# without threads, $filename is not defined until DB::DB is called 895share($main::{'_<'.$filename}) if defined $filename; 896 897# Command-line + PERLLIB: 898# Save the contents of @INC before they are modified elsewhere. 899@ini_INC = @INC; 900 901# This was an attempt to clear out the previous values of various 902# trapped errors. Apparently it didn't help. XXX More info needed! 903# $prevwarn = $prevdie = $prevbus = $prevsegv = ''; # Does not help?! 904 905# We set these variables to safe values. We don't want to blindly turn 906# off warnings, because other packages may still want them. 907$trace = $signal = $single = 0; # Uninitialized warning suppression 908 # (local $^W cannot help - other packages!). 909 910# Default to not exiting when program finishes; print the return 911# value when the 'r' command is used to return from a subroutine. 912$inhibit_exit = $option{PrintRet} = 1; 913 914use vars qw($trace_to_depth); 915 916# Default to 1E9 so it won't be limited to a certain recursion depth. 917$trace_to_depth = 1E9; 918 919=head1 OPTION PROCESSING 920 921The debugger's options are actually spread out over the debugger itself and 922C<dumpvar.pl>; some of these are variables to be set, while others are 923subs to be called with a value. To try to make this a little easier to 924manage, the debugger uses a few data structures to define what options 925are legal and how they are to be processed. 926 927First, the C<@options> array defines the I<names> of all the options that 928are to be accepted. 929 930=cut 931 932@options = qw( 933 CommandSet HistFile HistSize 934 hashDepth arrayDepth dumpDepth 935 DumpDBFiles DumpPackages DumpReused 936 compactDump veryCompact quote 937 HighBit undefPrint globPrint 938 PrintRet UsageOnly frame 939 AutoTrace TTY noTTY 940 ReadLine NonStop LineInfo 941 maxTraceLen recallCommand ShellBang 942 pager tkRunning ornaments 943 signalLevel warnLevel dieLevel 944 inhibit_exit ImmediateStop bareStringify 945 CreateTTY RemotePort windowSize 946 DollarCaretP 947); 948 949@RememberOnROptions = qw(DollarCaretP); 950 951=pod 952 953Second, C<optionVars> lists the variables that each option uses to save its 954state. 955 956=cut 957 958use vars qw(%optionVars); 959 960%optionVars = ( 961 hashDepth => \$dumpvar::hashDepth, 962 arrayDepth => \$dumpvar::arrayDepth, 963 CommandSet => \$CommandSet, 964 DumpDBFiles => \$dumpvar::dumpDBFiles, 965 DumpPackages => \$dumpvar::dumpPackages, 966 DumpReused => \$dumpvar::dumpReused, 967 HighBit => \$dumpvar::quoteHighBit, 968 undefPrint => \$dumpvar::printUndef, 969 globPrint => \$dumpvar::globPrint, 970 UsageOnly => \$dumpvar::usageOnly, 971 CreateTTY => \$CreateTTY, 972 bareStringify => \$dumpvar::bareStringify, 973 frame => \$frame, 974 AutoTrace => \$trace, 975 inhibit_exit => \$inhibit_exit, 976 maxTraceLen => \$maxtrace, 977 ImmediateStop => \$ImmediateStop, 978 RemotePort => \$remoteport, 979 windowSize => \$window, 980 HistFile => \$histfile, 981 HistSize => \$histsize, 982); 983 984=pod 985 986Third, C<%optionAction> defines the subroutine to be called to process each 987option. 988 989=cut 990 991use vars qw(%optionAction); 992 993%optionAction = ( 994 compactDump => \&dumpvar::compactDump, 995 veryCompact => \&dumpvar::veryCompact, 996 quote => \&dumpvar::quote, 997 TTY => \&TTY, 998 noTTY => \&noTTY, 999 ReadLine => \&ReadLine, 1000 NonStop => \&NonStop, 1001 LineInfo => \&LineInfo, 1002 recallCommand => \&recallCommand, 1003 ShellBang => \&shellBang, 1004 pager => \&pager, 1005 signalLevel => \&signalLevel, 1006 warnLevel => \&warnLevel, 1007 dieLevel => \&dieLevel, 1008 tkRunning => \&tkRunning, 1009 ornaments => \&ornaments, 1010 RemotePort => \&RemotePort, 1011 DollarCaretP => \&DollarCaretP, 1012); 1013 1014=pod 1015 1016Last, the C<%optionRequire> notes modules that must be C<require>d if an 1017option is used. 1018 1019=cut 1020 1021# Note that this list is not complete: several options not listed here 1022# actually require that dumpvar.pl be loaded for them to work, but are 1023# not in the table. A subsequent patch will correct this problem; for 1024# the moment, we're just recommenting, and we are NOT going to change 1025# function. 1026use vars qw(%optionRequire); 1027 1028%optionRequire = ( 1029 compactDump => 'dumpvar.pl', 1030 veryCompact => 'dumpvar.pl', 1031 quote => 'dumpvar.pl', 1032); 1033 1034=pod 1035 1036There are a number of initialization-related variables which can be set 1037by putting code to set them in a BEGIN block in the C<PERL5DB> environment 1038variable. These are: 1039 1040=over 4 1041 1042=item C<$rl> - readline control XXX needs more explanation 1043 1044=item C<$warnLevel> - whether or not debugger takes over warning handling 1045 1046=item C<$dieLevel> - whether or not debugger takes over die handling 1047 1048=item C<$signalLevel> - whether or not debugger takes over signal handling 1049 1050=item C<$pre> - preprompt actions (array reference) 1051 1052=item C<$post> - postprompt actions (array reference) 1053 1054=item C<$pretype> 1055 1056=item C<$CreateTTY> - whether or not to create a new TTY for this debugger 1057 1058=item C<$CommandSet> - which command set to use (defaults to new, documented set) 1059 1060=back 1061 1062=cut 1063 1064# These guys may be defined in $ENV{PERL5DB} : 1065$rl = 1 unless defined $rl; 1066$warnLevel = 1 unless defined $warnLevel; 1067$dieLevel = 1 unless defined $dieLevel; 1068$signalLevel = 1 unless defined $signalLevel; 1069$pre = [] unless defined $pre; 1070$post = [] unless defined $post; 1071$pretype = [] unless defined $pretype; 1072$CreateTTY = 3 unless defined $CreateTTY; 1073$CommandSet = '580' unless defined $CommandSet; 1074 1075share($rl); 1076share($warnLevel); 1077share($dieLevel); 1078share($signalLevel); 1079share($pre); 1080share($post); 1081share($pretype); 1082share($rl); 1083share($CreateTTY); 1084share($CommandSet); 1085 1086=pod 1087 1088The default C<die>, C<warn>, and C<signal> handlers are set up. 1089 1090=cut 1091 1092warnLevel($warnLevel); 1093dieLevel($dieLevel); 1094signalLevel($signalLevel); 1095 1096=pod 1097 1098The pager to be used is needed next. We try to get it from the 1099environment first. If it's not defined there, we try to find it in 1100the Perl C<Config.pm>. If it's not there, we default to C<more>. We 1101then call the C<pager()> function to save the pager name. 1102 1103=cut 1104 1105# This routine makes sure $pager is set up so that '|' can use it. 1106pager( 1107 1108 # If PAGER is defined in the environment, use it. 1109 defined $ENV{PAGER} 1110 ? $ENV{PAGER} 1111 1112 # If not, see if Config.pm defines it. 1113 : eval { require Config } 1114 && defined $Config::Config{pager} 1115 ? $Config::Config{pager} 1116 1117 # If not, fall back to 'more'. 1118 : 'more' 1119 ) 1120 unless defined $pager; 1121 1122=pod 1123 1124We set up the command to be used to access the man pages, the command 1125recall character (C<!> unless otherwise defined) and the shell escape 1126character (C<!> unless otherwise defined). Yes, these do conflict, and 1127neither works in the debugger at the moment. 1128 1129=cut 1130 1131setman(); 1132 1133# Set up defaults for command recall and shell escape (note: 1134# these currently don't work in linemode debugging). 1135recallCommand("!") unless defined $prc; 1136shellBang("!") unless defined $psh; 1137 1138=pod 1139 1140We then set up the gigantic string containing the debugger help. 1141We also set the limit on the number of arguments we'll display during a 1142trace. 1143 1144=cut 1145 1146sethelp(); 1147 1148# If we didn't get a default for the length of eval/stack trace args, 1149# set it here. 1150$maxtrace = 400 unless defined $maxtrace; 1151 1152=head2 SETTING UP THE DEBUGGER GREETING 1153 1154The debugger I<greeting> helps to inform the user how many debuggers are 1155running, and whether the current debugger is the primary or a child. 1156 1157If we are the primary, we just hang onto our pid so we'll have it when 1158or if we start a child debugger. If we are a child, we'll set things up 1159so we'll have a unique greeting and so the parent will give us our own 1160TTY later. 1161 1162We save the current contents of the C<PERLDB_PIDS> environment variable 1163because we mess around with it. We'll also need to hang onto it because 1164we'll need it if we restart. 1165 1166Child debuggers make a label out of the current PID structure recorded in 1167PERLDB_PIDS plus the new PID. They also mark themselves as not having a TTY 1168yet so the parent will give them one later via C<resetterm()>. 1169 1170=cut 1171 1172# Save the current contents of the environment; we're about to 1173# much with it. We'll need this if we have to restart. 1174use vars qw($ini_pids); 1175$ini_pids = $ENV{PERLDB_PIDS}; 1176 1177use vars qw ($pids $term_pid); 1178 1179if ( defined $ENV{PERLDB_PIDS} ) { 1180 1181 # We're a child. Make us a label out of the current PID structure 1182 # recorded in PERLDB_PIDS plus our (new) PID. Mark us as not having 1183 # a term yet so the parent will give us one later via resetterm(). 1184 1185 my $env_pids = $ENV{PERLDB_PIDS}; 1186 $pids = "[$env_pids]"; 1187 1188 # Unless we are on OpenVMS, all programs under the DCL shell run under 1189 # the same PID. 1190 1191 if (($^O eq 'VMS') && ($env_pids =~ /\b$$\b/)) { 1192 $term_pid = $$; 1193 } 1194 else { 1195 $ENV{PERLDB_PIDS} .= "->$$"; 1196 $term_pid = -1; 1197 } 1198 1199} ## end if (defined $ENV{PERLDB_PIDS... 1200else { 1201 1202 # We're the parent PID. Initialize PERLDB_PID in case we end up with a 1203 # child debugger, and mark us as the parent, so we'll know to set up 1204 # more TTY's is we have to. 1205 $ENV{PERLDB_PIDS} = "$$"; 1206 $pids = "[pid=$$]"; 1207 $term_pid = $$; 1208} 1209 1210use vars qw($pidprompt); 1211$pidprompt = ''; 1212 1213# Sets up $emacs as a synonym for $slave_editor. 1214our ($slave_editor); 1215*emacs = $slave_editor if $slave_editor; # May be used in afterinit()... 1216 1217=head2 READING THE RC FILE 1218 1219The debugger will read a file of initialization options if supplied. If 1220running interactively, this is C<.perldb>; if not, it's C<perldb.ini>. 1221 1222=cut 1223 1224# As noted, this test really doesn't check accurately that the debugger 1225# is running at a terminal or not. 1226 1227use vars qw($rcfile); 1228{ 1229 my $dev_tty = (($^O eq 'VMS') ? 'TT:' : '/dev/tty'); 1230 # this is the wrong metric! 1231 $rcfile = ((-e $dev_tty) ? ".perldb" : "perldb.ini"); 1232} 1233 1234=pod 1235 1236The debugger does a safety test of the file to be read. It must be owned 1237either by the current user or root, and must only be writable by the owner. 1238 1239=cut 1240 1241# This wraps a safety test around "do" to read and evaluate the init file. 1242# 1243# This isn't really safe, because there's a race 1244# between checking and opening. The solution is to 1245# open and fstat the handle, but then you have to read and 1246# eval the contents. But then the silly thing gets 1247# your lexical scope, which is unfortunate at best. 1248sub safe_do { 1249 my $file = shift; 1250 1251 # Just exactly what part of the word "CORE::" don't you understand? 1252 local $SIG{__WARN__}; 1253 local $SIG{__DIE__}; 1254 1255 unless ( is_safe_file($file) ) { 1256 CORE::warn <<EO_GRIPE; 1257perldb: Must not source insecure rcfile $file. 1258 You or the superuser must be the owner, and it must not 1259 be writable by anyone but its owner. 1260EO_GRIPE 1261 return; 1262 } ## end unless (is_safe_file($file... 1263 1264 do $file; 1265 CORE::warn("perldb: couldn't parse $file: $@") if $@; 1266} ## end sub safe_do 1267 1268# This is the safety test itself. 1269# 1270# Verifies that owner is either real user or superuser and that no 1271# one but owner may write to it. This function is of limited use 1272# when called on a path instead of upon a handle, because there are 1273# no guarantees that filename (by dirent) whose file (by ino) is 1274# eventually accessed is the same as the one tested. 1275# Assumes that the file's existence is not in doubt. 1276sub is_safe_file { 1277 my $path = shift; 1278 stat($path) || return; # mysteriously vaporized 1279 my ( $dev, $ino, $mode, $nlink, $uid, $gid ) = stat(_); 1280 1281 return 0 if $uid != 0 && $uid != $<; 1282 return 0 if $mode & 022; 1283 return 1; 1284} ## end sub is_safe_file 1285 1286# If the rcfile (whichever one we decided was the right one to read) 1287# exists, we safely do it. 1288if ( -f $rcfile ) { 1289 safe_do("./$rcfile"); 1290} 1291 1292# If there isn't one here, try the user's home directory. 1293elsif ( defined $ENV{HOME} && -f "$ENV{HOME}/$rcfile" ) { 1294 safe_do("$ENV{HOME}/$rcfile"); 1295} 1296 1297# Else try the login directory. 1298elsif ( defined $ENV{LOGDIR} && -f "$ENV{LOGDIR}/$rcfile" ) { 1299 safe_do("$ENV{LOGDIR}/$rcfile"); 1300} 1301 1302# If the PERLDB_OPTS variable has options in it, parse those out next. 1303if ( defined $ENV{PERLDB_OPTS} ) { 1304 parse_options( $ENV{PERLDB_OPTS} ); 1305} 1306 1307=pod 1308 1309The last thing we do during initialization is determine which subroutine is 1310to be used to obtain a new terminal when a new debugger is started. Right now, 1311the debugger only handles TCP sockets, X11, OS/2, amd Mac OS X 1312(darwin). 1313 1314=cut 1315 1316# Set up the get_fork_TTY subroutine to be aliased to the proper routine. 1317# Works if you're running an xterm or xterm-like window, or you're on 1318# OS/2, or on Mac OS X. This may need some expansion. 1319 1320if (not defined &get_fork_TTY) # only if no routine exists 1321{ 1322 if ( defined $remoteport ) { 1323 # Expect an inetd-like server 1324 *get_fork_TTY = \&socket_get_fork_TTY; # to listen to us 1325 } 1326 elsif (defined $ENV{TERM} # If we know what kind 1327 # of terminal this is, 1328 and $ENV{TERM} eq 'xterm' # and it's an xterm, 1329 and defined $ENV{DISPLAY} # and what display it's on, 1330 ) 1331 { 1332 *get_fork_TTY = \&xterm_get_fork_TTY; # use the xterm version 1333 } 1334 elsif ( $^O eq 'os2' ) { # If this is OS/2, 1335 *get_fork_TTY = \&os2_get_fork_TTY; # use the OS/2 version 1336 } 1337 elsif ( $^O eq 'darwin' # If this is Mac OS X 1338 and defined $ENV{TERM_PROGRAM} # and we're running inside 1339 and $ENV{TERM_PROGRAM} 1340 eq 'Apple_Terminal' # Terminal.app 1341 ) 1342 { 1343 *get_fork_TTY = \&macosx_get_fork_TTY; # use the Mac OS X version 1344 } 1345} ## end if (not defined &get_fork_TTY... 1346 1347# untaint $^O, which may have been tainted by the last statement. 1348# see bug [perl #24674] 1349$^O =~ m/^(.*)\z/; 1350$^O = $1; 1351 1352# Here begin the unreadable code. It needs fixing. 1353 1354=head2 RESTART PROCESSING 1355 1356This section handles the restart command. When the C<R> command is invoked, it 1357tries to capture all of the state it can into environment variables, and 1358then sets C<PERLDB_RESTART>. When we start executing again, we check to see 1359if C<PERLDB_RESTART> is there; if so, we reload all the information that 1360the R command stuffed into the environment variables. 1361 1362 PERLDB_RESTART - flag only, contains no restart data itself. 1363 PERLDB_HIST - command history, if it's available 1364 PERLDB_ON_LOAD - breakpoints set by the rc file 1365 PERLDB_POSTPONE - subs that have been loaded/not executed, and have actions 1366 PERLDB_VISITED - files that had breakpoints 1367 PERLDB_FILE_... - breakpoints for a file 1368 PERLDB_OPT - active options 1369 PERLDB_INC - the original @INC 1370 PERLDB_PRETYPE - preprompt debugger actions 1371 PERLDB_PRE - preprompt Perl code 1372 PERLDB_POST - post-prompt Perl code 1373 PERLDB_TYPEAHEAD - typeahead captured by readline() 1374 1375We chug through all these variables and plug the values saved in them 1376back into the appropriate spots in the debugger. 1377 1378=cut 1379 1380use vars qw(%postponed_file @typeahead); 1381 1382our (@hist, @truehist); 1383 1384sub _restore_shared_globals_after_restart 1385{ 1386 @hist = get_list('PERLDB_HIST'); 1387 %break_on_load = get_list("PERLDB_ON_LOAD"); 1388 %postponed = get_list("PERLDB_POSTPONE"); 1389 1390 share(@hist); 1391 share(@truehist); 1392 share(%break_on_load); 1393 share(%postponed); 1394} 1395 1396sub _restore_breakpoints_and_actions { 1397 1398 my @had_breakpoints = get_list("PERLDB_VISITED"); 1399 1400 for my $file_idx ( 0 .. $#had_breakpoints ) { 1401 my $filename = $had_breakpoints[$file_idx]; 1402 my %pf = get_list("PERLDB_FILE_$file_idx"); 1403 $postponed_file{ $filename } = \%pf if %pf; 1404 my @lines = sort {$a <=> $b} keys(%pf); 1405 my @enabled_statuses = get_list("PERLDB_FILE_ENABLED_$file_idx"); 1406 for my $line_idx (0 .. $#lines) { 1407 _set_breakpoint_enabled_status( 1408 $filename, 1409 $lines[$line_idx], 1410 ($enabled_statuses[$line_idx] ? 1 : ''), 1411 ); 1412 } 1413 } 1414 1415 return; 1416} 1417 1418sub _restore_options_after_restart 1419{ 1420 my %options_map = get_list("PERLDB_OPT"); 1421 1422 while ( my ( $opt, $val ) = each %options_map ) { 1423 $val =~ s/[\\\']/\\$1/g; 1424 parse_options("$opt'$val'"); 1425 } 1426 1427 return; 1428} 1429 1430sub _restore_globals_after_restart 1431{ 1432 # restore original @INC 1433 @INC = get_list("PERLDB_INC"); 1434 @ini_INC = @INC; 1435 1436 # return pre/postprompt actions and typeahead buffer 1437 $pretype = [ get_list("PERLDB_PRETYPE") ]; 1438 $pre = [ get_list("PERLDB_PRE") ]; 1439 $post = [ get_list("PERLDB_POST") ]; 1440 @typeahead = get_list( "PERLDB_TYPEAHEAD", @typeahead ); 1441 1442 return; 1443} 1444 1445 1446if ( exists $ENV{PERLDB_RESTART} ) { 1447 1448 # We're restarting, so we don't need the flag that says to restart anymore. 1449 delete $ENV{PERLDB_RESTART}; 1450 1451 # $restart = 1; 1452 _restore_shared_globals_after_restart(); 1453 1454 _restore_breakpoints_and_actions(); 1455 1456 # restore options 1457 _restore_options_after_restart(); 1458 1459 _restore_globals_after_restart(); 1460} ## end if (exists $ENV{PERLDB_RESTART... 1461 1462=head2 SETTING UP THE TERMINAL 1463 1464Now, we'll decide how the debugger is going to interact with the user. 1465If there's no TTY, we set the debugger to run non-stop; there's not going 1466to be anyone there to enter commands. 1467 1468=cut 1469 1470use vars qw($notty $console $tty $LINEINFO); 1471use vars qw($lineinfo $doccmd); 1472 1473our ($runnonstop); 1474 1475# Local autoflush to avoid rt#116769, 1476# as calling IO::File methods causes an unresolvable loop 1477# that results in debugger failure. 1478sub _autoflush { 1479 my $o = select($_[0]); 1480 $|++; 1481 select($o); 1482} 1483 1484if ($notty) { 1485 $runnonstop = 1; 1486 share($runnonstop); 1487} 1488 1489=pod 1490 1491If there is a TTY, we have to determine who it belongs to before we can 1492proceed. If this is a slave editor or graphical debugger (denoted by 1493the first command-line switch being '-emacs'), we shift this off and 1494set C<$rl> to 0 (XXX ostensibly to do straight reads). 1495 1496=cut 1497 1498else { 1499 1500 # Is Perl being run from a slave editor or graphical debugger? 1501 # If so, don't use readline, and set $slave_editor = 1. 1502 if ($slave_editor = ( @main::ARGV && ( $main::ARGV[0] eq '-emacs' ) )) { 1503 $rl = 0; 1504 shift(@main::ARGV); 1505 } 1506 1507 #require Term::ReadLine; 1508 1509=pod 1510 1511We then determine what the console should be on various systems: 1512 1513=over 4 1514 1515=item * Cygwin - We use C<stdin> instead of a separate device. 1516 1517=cut 1518 1519 if ( $^O eq 'cygwin' ) { 1520 1521 # /dev/tty is binary. use stdin for textmode 1522 undef $console; 1523 } 1524 1525=item * Unix - use F</dev/tty>. 1526 1527=cut 1528 1529 elsif ( -e "/dev/tty" ) { 1530 $console = "/dev/tty"; 1531 } 1532 1533=item * Windows or MSDOS - use C<con>. 1534 1535=cut 1536 1537 elsif ( $^O eq 'dos' or -e "con" or $^O eq 'MSWin32' ) { 1538 $console = "con"; 1539 } 1540 1541=item * VMS - use C<sys$command>. 1542 1543=cut 1544 1545 else { 1546 1547 # everything else is ... 1548 $console = "sys\$command"; 1549 } 1550 1551=pod 1552 1553=back 1554 1555Several other systems don't use a specific console. We C<undef $console> 1556for those (Windows using a slave editor/graphical debugger, NetWare, OS/2 1557with a slave editor). 1558 1559=cut 1560 1561 if ( ( $^O eq 'MSWin32' ) and ( $slave_editor or defined $ENV{EMACS} ) ) { 1562 1563 # /dev/tty is binary. use stdin for textmode 1564 $console = undef; 1565 } 1566 1567 if ( $^O eq 'NetWare' ) { 1568 1569 # /dev/tty is binary. use stdin for textmode 1570 $console = undef; 1571 } 1572 1573 # In OS/2, we need to use STDIN to get textmode too, even though 1574 # it pretty much looks like Unix otherwise. 1575 if ( defined $ENV{OS2_SHELL} and ( $slave_editor or $ENV{WINDOWID} ) ) 1576 { # In OS/2 1577 $console = undef; 1578 } 1579 1580=pod 1581 1582If there is a TTY hanging around from a parent, we use that as the console. 1583 1584=cut 1585 1586 $console = $tty if defined $tty; 1587 1588=head2 SOCKET HANDLING 1589 1590The debugger is capable of opening a socket and carrying out a debugging 1591session over the socket. 1592 1593If C<RemotePort> was defined in the options, the debugger assumes that it 1594should try to start a debugging session on that port. It builds the socket 1595and then tries to connect the input and output filehandles to it. 1596 1597=cut 1598 1599 # Handle socket stuff. 1600 1601 if ( defined $remoteport ) { 1602 1603 # If RemotePort was defined in the options, connect input and output 1604 # to the socket. 1605 $IN = $OUT = connect_remoteport(); 1606 } ## end if (defined $remoteport) 1607 1608=pod 1609 1610If no C<RemotePort> was defined, and we want to create a TTY on startup, 1611this is probably a situation where multiple debuggers are running (for example, 1612a backticked command that starts up another debugger). We create a new IN and 1613OUT filehandle, and do the necessary mojo to create a new TTY if we know how 1614and if we can. 1615 1616=cut 1617 1618 # Non-socket. 1619 else { 1620 1621 # Two debuggers running (probably a system or a backtick that invokes 1622 # the debugger itself under the running one). create a new IN and OUT 1623 # filehandle, and do the necessary mojo to create a new tty if we 1624 # know how, and we can. 1625 create_IN_OUT(4) if $CreateTTY & 4; 1626 if ($console) { 1627 1628 # If we have a console, check to see if there are separate ins and 1629 # outs to open. (They are assumed identical if not.) 1630 1631 my ( $i, $o ) = split /,/, $console; 1632 $o = $i unless defined $o; 1633 1634 # read/write on in, or just read, or read on STDIN. 1635 open( IN, "+<$i" ) 1636 || open( IN, "<$i" ) 1637 || open( IN, "<&STDIN" ); 1638 1639 # read/write/create/clobber out, or write/create/clobber out, 1640 # or merge with STDERR, or merge with STDOUT. 1641 open( OUT, "+>$o" ) 1642 || open( OUT, ">$o" ) 1643 || open( OUT, ">&STDERR" ) 1644 || open( OUT, ">&STDOUT" ); # so we don't dongle stdout 1645 1646 } ## end if ($console) 1647 elsif ( not defined $console ) { 1648 1649 # No console. Open STDIN. 1650 open( IN, "<&STDIN" ); 1651 1652 # merge with STDERR, or with STDOUT. 1653 open( OUT, ">&STDERR" ) 1654 || open( OUT, ">&STDOUT" ); # so we don't dongle stdout 1655 $console = 'STDIN/OUT'; 1656 } ## end elsif (not defined $console) 1657 1658 # Keep copies of the filehandles so that when the pager runs, it 1659 # can close standard input without clobbering ours. 1660 if ($console or (not defined($console))) { 1661 $IN = \*IN; 1662 $OUT = \*OUT; 1663 } 1664 } ## end elsif (from if(defined $remoteport)) 1665 1666 # Unbuffer DB::OUT. We need to see responses right away. 1667 _autoflush($OUT); 1668 1669 # Line info goes to debugger output unless pointed elsewhere. 1670 # Pointing elsewhere makes it possible for slave editors to 1671 # keep track of file and position. We have both a filehandle 1672 # and a I/O description to keep track of. 1673 $LINEINFO = $OUT unless defined $LINEINFO; 1674 $lineinfo = $console unless defined $lineinfo; 1675 # share($LINEINFO); # <- unable to share globs 1676 share($lineinfo); # 1677 1678=pod 1679 1680To finish initialization, we show the debugger greeting, 1681and then call the C<afterinit()> subroutine if there is one. 1682 1683=cut 1684 1685 # Show the debugger greeting. 1686 $header =~ s/.Header: ([^,]+),v(\s+\S+\s+\S+).*$/$1$2/; 1687 unless ($runnonstop) { 1688 local $\ = ''; 1689 local $, = ''; 1690 if ( $term_pid eq '-1' ) { 1691 print $OUT "\nDaughter DB session started...\n"; 1692 } 1693 else { 1694 print $OUT "\nLoading DB routines from $header\n"; 1695 print $OUT ( 1696 "Editor support ", 1697 $slave_editor ? "enabled" : "available", ".\n" 1698 ); 1699 print $OUT 1700"\nEnter h or 'h h' for help, or '$doccmd perldebug' for more help.\n\n"; 1701 } ## end else [ if ($term_pid eq '-1') 1702 } ## end unless ($runnonstop) 1703} ## end else [ if ($notty) 1704 1705# XXX This looks like a bug to me. 1706# Why copy to @ARGS and then futz with @args? 1707@ARGS = @ARGV; 1708# for (@args) { 1709 # Make sure backslashes before single quotes are stripped out, and 1710 # keep args unless they are numeric (XXX why?) 1711 # s/\'/\\\'/g; # removed while not justified understandably 1712 # s/(.*)/'$1'/ unless /^-?[\d.]+$/; # ditto 1713# } 1714 1715# If there was an afterinit() sub defined, call it. It will get 1716# executed in our scope, so it can fiddle with debugger globals. 1717if ( defined &afterinit ) { # May be defined in $rcfile 1718 afterinit(); 1719} 1720 1721# Inform us about "Stack dump during die enabled ..." in dieLevel(). 1722use vars qw($I_m_init); 1723 1724$I_m_init = 1; 1725 1726############################################################ Subroutines 1727 1728=head1 SUBROUTINES 1729 1730=head2 DB 1731 1732This gigantic subroutine is the heart of the debugger. Called before every 1733statement, its job is to determine if a breakpoint has been reached, and 1734stop if so; read commands from the user, parse them, and execute 1735them, and then send execution off to the next statement. 1736 1737Note that the order in which the commands are processed is very important; 1738some commands earlier in the loop will actually alter the C<$cmd> variable 1739to create other commands to be executed later. This is all highly I<optimized> 1740but can be confusing. Check the comments for each C<$cmd ... && do {}> to 1741see what's happening in any given command. 1742 1743=cut 1744 1745# $cmd cannot be an our() variable unfortunately (possible perl bug?). 1746 1747use vars qw( 1748 $action 1749 $cmd 1750 $file 1751 $filename_ini 1752 $finished 1753 %had_breakpoints 1754 $level 1755 $max 1756 $package 1757 $try 1758); 1759 1760our ( 1761 %alias, 1762 $doret, 1763 $end, 1764 $fall_off_end, 1765 $incr, 1766 $laststep, 1767 $rc, 1768 $sh, 1769 $stack_depth, 1770 @stack, 1771 @to_watch, 1772 @old_watch, 1773); 1774 1775sub _DB__determine_if_we_should_break 1776{ 1777 # if we have something here, see if we should break. 1778 # $stop is lexical and local to this block - $action on the other hand 1779 # is global. 1780 my $stop; 1781 1782 if ( $dbline{$line} 1783 && _is_breakpoint_enabled($filename, $line) 1784 && (( $stop, $action ) = split( /\0/, $dbline{$line} ) ) ) 1785 { 1786 1787 # Stop if the stop criterion says to just stop. 1788 if ( $stop eq '1' ) { 1789 $signal |= 1; 1790 } 1791 1792 # It's a conditional stop; eval it in the user's context and 1793 # see if we should stop. If so, remove the one-time sigil. 1794 elsif ($stop) { 1795 $evalarg = "\$DB::signal |= 1 if do {$stop}"; 1796 # The &-call is here to ascertain the mutability of @_. 1797 &DB::eval; 1798 # If the breakpoint is temporary, then delete its enabled status. 1799 if ($dbline{$line} =~ s/;9($|\0)/$1/) { 1800 _cancel_breakpoint_temp_enabled_status($filename, $line); 1801 } 1802 } 1803 } ## end if ($dbline{$line} && ... 1804} 1805 1806sub _DB__is_finished { 1807 if ($finished and $level <= 1) { 1808 end_report(); 1809 return 1; 1810 } 1811 else { 1812 return; 1813 } 1814} 1815 1816sub _DB__read_next_cmd 1817{ 1818 my ($tid) = @_; 1819 1820 # We have a terminal, or can get one ... 1821 if (!$term) { 1822 setterm(); 1823 } 1824 1825 # ... and it belogs to this PID or we get one for this PID ... 1826 if ($term_pid != $$) { 1827 resetterm(1); 1828 } 1829 1830 # ... and we got a line of command input ... 1831 $cmd = DB::readline( 1832 "$pidprompt $tid DB" 1833 . ( '<' x $level ) 1834 . ( $#hist + 1 ) 1835 . ( '>' x $level ) . " " 1836 ); 1837 1838 return defined($cmd); 1839} 1840 1841sub _DB__trim_command_and_return_first_component { 1842 my ($obj) = @_; 1843 1844 $cmd =~ s/\A\s+//s; # trim annoying leading whitespace 1845 $cmd =~ s/\s+\z//s; # trim annoying trailing whitespace 1846 1847 my ($verb, $args) = $cmd =~ m{\A(\S*)\s*(.*)}s; 1848 1849 $obj->cmd_verb($verb); 1850 $obj->cmd_args($args); 1851 1852 return; 1853} 1854 1855sub _DB__handle_f_command { 1856 my ($obj) = @_; 1857 1858 if ($file = $obj->cmd_args) { 1859 # help for no arguments (old-style was return from sub). 1860 if ( !$file ) { 1861 print $OUT 1862 "The old f command is now the r command.\n"; # hint 1863 print $OUT "The new f command switches filenames.\n"; 1864 next CMD; 1865 } ## end if (!$file) 1866 1867 # if not in magic file list, try a close match. 1868 if ( !defined $main::{ '_<' . $file } ) { 1869 if ( ($try) = grep( m#^_<.*$file#, keys %main:: ) ) { 1870 { 1871 $try = substr( $try, 2 ); 1872 print $OUT "Choosing $try matching '$file':\n"; 1873 $file = $try; 1874 } 1875 } ## end if (($try) = grep(m#^_<.*$file#... 1876 } ## end if (!defined $main::{ ... 1877 1878 # If not successfully switched now, we failed. 1879 if ( !defined $main::{ '_<' . $file } ) { 1880 print $OUT "No file matching '$file' is loaded.\n"; 1881 next CMD; 1882 } 1883 1884 # We switched, so switch the debugger internals around. 1885 elsif ( $file ne $filename ) { 1886 *dbline = $main::{ '_<' . $file }; 1887 $max = $#dbline; 1888 $filename = $file; 1889 $start = 1; 1890 $cmd = "l"; 1891 } ## end elsif ($file ne $filename) 1892 1893 # We didn't switch; say we didn't. 1894 else { 1895 print $OUT "Already in $file.\n"; 1896 next CMD; 1897 } 1898 } 1899 1900 return; 1901} 1902 1903sub _DB__handle_dot_command { 1904 my ($obj) = @_; 1905 1906 # . command. 1907 if ($obj->_is_full('.')) { 1908 $incr = -1; # stay at current line 1909 1910 # Reset everything to the old location. 1911 $start = $line; 1912 $filename = $filename_ini; 1913 *dbline = $main::{ '_<' . $filename }; 1914 $max = $#dbline; 1915 1916 # Now where are we? 1917 print_lineinfo($obj->position()); 1918 next CMD; 1919 } 1920 1921 return; 1922} 1923 1924sub _DB__handle_y_command { 1925 my ($obj) = @_; 1926 1927 if (my ($match_level, $match_vars) 1928 = $obj->cmd_args =~ /\A(?:(\d*)\s*(.*))?\z/) { 1929 1930 # See if we've got the necessary support. 1931 if (!eval { require PadWalker; PadWalker->VERSION(0.08) }) { 1932 my $Err = $@; 1933 _db_warn( 1934 $Err =~ /locate/ 1935 ? "PadWalker module not found - please install\n" 1936 : $Err 1937 ); 1938 next CMD; 1939 } 1940 1941 # Load up dumpvar if we don't have it. If we can, that is. 1942 do 'dumpvar.pl' || die $@ unless defined &main::dumpvar; 1943 defined &main::dumpvar 1944 or print $OUT "dumpvar.pl not available.\n" 1945 and next CMD; 1946 1947 # Got all the modules we need. Find them and print them. 1948 my @vars = split( ' ', $match_vars || '' ); 1949 1950 # Find the pad. 1951 my $h = eval { PadWalker::peek_my( ( $match_level || 0 ) + 1 ) }; 1952 1953 # Oops. Can't find it. 1954 if (my $Err = $@) { 1955 $Err =~ s/ at .*//; 1956 _db_warn($Err); 1957 next CMD; 1958 } 1959 1960 # Show the desired vars with dumplex(). 1961 my $savout = select($OUT); 1962 1963 # Have dumplex dump the lexicals. 1964 foreach my $key (sort keys %$h) { 1965 dumpvar::dumplex( $key, $h->{$key}, 1966 defined $option{dumpDepth} ? $option{dumpDepth} : -1, 1967 @vars ); 1968 } 1969 select($savout); 1970 next CMD; 1971 } 1972} 1973 1974sub _DB__handle_c_command { 1975 my ($obj) = @_; 1976 1977 my $i = $obj->cmd_args; 1978 1979 if ($i =~ m#\A[\w:]*\z#) { 1980 1981 # Hey, show's over. The debugged program finished 1982 # executing already. 1983 next CMD if _DB__is_finished(); 1984 1985 # Capture the place to put a one-time break. 1986 $subname = $i; 1987 1988 # Probably not needed, since we finish an interactive 1989 # sub-session anyway... 1990 # local $filename = $filename; 1991 # local *dbline = *dbline; # XXX Would this work?! 1992 # 1993 # The above question wonders if localizing the alias 1994 # to the magic array works or not. Since it's commented 1995 # out, we'll just leave that to speculation for now. 1996 1997 # If the "subname" isn't all digits, we'll assume it 1998 # is a subroutine name, and try to find it. 1999 if ( $subname =~ /\D/ ) { # subroutine name 2000 # Qualify it to the current package unless it's 2001 # already qualified. 2002 $subname = $package . "::" . $subname 2003 unless $subname =~ /::/; 2004 2005 # find_sub will return "file:line_number" corresponding 2006 # to where the subroutine is defined; we call find_sub, 2007 # break up the return value, and assign it in one 2008 # operation. 2009 ( $file, $i ) = ( find_sub($subname) =~ /^(.*):(.*)$/ ); 2010 2011 # Force the line number to be numeric. 2012 $i = $i + 0; 2013 2014 # If we got a line number, we found the sub. 2015 if ($i) { 2016 2017 # Switch all the debugger's internals around so 2018 # we're actually working with that file. 2019 $filename = $file; 2020 *dbline = $main::{ '_<' . $filename }; 2021 2022 # Mark that there's a breakpoint in this file. 2023 $had_breakpoints{$filename} |= 1; 2024 2025 # Scan forward to the first executable line 2026 # after the 'sub whatever' line. 2027 $max = $#dbline; 2028 my $_line_num = $i; 2029 while ($dbline[$_line_num] == 0 && $_line_num< $max) 2030 { 2031 $_line_num++; 2032 } 2033 $i = $_line_num; 2034 } ## end if ($i) 2035 2036 # We didn't find a sub by that name. 2037 else { 2038 print $OUT "Subroutine $subname not found.\n"; 2039 next CMD; 2040 } 2041 } ## end if ($subname =~ /\D/) 2042 2043 # At this point, either the subname was all digits (an 2044 # absolute line-break request) or we've scanned through 2045 # the code following the definition of the sub, looking 2046 # for an executable, which we may or may not have found. 2047 # 2048 # If $i (which we set $subname from) is non-zero, we 2049 # got a request to break at some line somewhere. On 2050 # one hand, if there wasn't any real subroutine name 2051 # involved, this will be a request to break in the current 2052 # file at the specified line, so we have to check to make 2053 # sure that the line specified really is breakable. 2054 # 2055 # On the other hand, if there was a subname supplied, the 2056 # preceding block has moved us to the proper file and 2057 # location within that file, and then scanned forward 2058 # looking for the next executable line. We have to make 2059 # sure that one was found. 2060 # 2061 # On the gripping hand, we can't do anything unless the 2062 # current value of $i points to a valid breakable line. 2063 # Check that. 2064 if ($i) { 2065 2066 # Breakable? 2067 if ( $dbline[$i] == 0 ) { 2068 print $OUT "Line $i not breakable.\n"; 2069 next CMD; 2070 } 2071 2072 # Yes. Set up the one-time-break sigil. 2073 $dbline{$i} =~ s/($|\0)/;9$1/; # add one-time-only b.p. 2074 _enable_breakpoint_temp_enabled_status($filename, $i); 2075 } ## end if ($i) 2076 2077 # Turn off stack tracing from here up. 2078 for my $j (0 .. $stack_depth) { 2079 $stack[ $j ] &= ~1; 2080 } 2081 last CMD; 2082 } 2083 2084 return; 2085} 2086 2087sub _DB__handle_forward_slash_command { 2088 my ($obj) = @_; 2089 2090 # The pattern as a string. 2091 use vars qw($inpat); 2092 2093 if (($inpat) = $cmd =~ m#\A/(.*)\z#) { 2094 2095 # Remove the final slash. 2096 $inpat =~ s:([^\\])/$:$1:; 2097 2098 # If the pattern isn't null ... 2099 if ( $inpat ne "" ) { 2100 2101 # Turn of warn and die procesing for a bit. 2102 local $SIG{__DIE__}; 2103 local $SIG{__WARN__}; 2104 2105 # Create the pattern. 2106 eval 'no strict q/vars/; $inpat =~ m' . "\a$inpat\a"; 2107 if ( $@ ne "" ) { 2108 2109 # Oops. Bad pattern. No biscuit. 2110 # Print the eval error and go back for more 2111 # commands. 2112 print {$OUT} "$@"; 2113 next CMD; 2114 } 2115 $obj->pat($inpat); 2116 } ## end if ($inpat ne "") 2117 2118 # Set up to stop on wrap-around. 2119 $end = $start; 2120 2121 # Don't move off the current line. 2122 $incr = -1; 2123 2124 my $pat = $obj->pat; 2125 2126 # Done in eval so nothing breaks if the pattern 2127 # does something weird. 2128 eval 2129 { 2130 no strict q/vars/; 2131 for (;;) { 2132 # Move ahead one line. 2133 ++$start; 2134 2135 # Wrap if we pass the last line. 2136 if ($start > $max) { 2137 $start = 1; 2138 } 2139 2140 # Stop if we have gotten back to this line again, 2141 last if ($start == $end); 2142 2143 # A hit! (Note, though, that we are doing 2144 # case-insensitive matching. Maybe a qr// 2145 # expression would be better, so the user could 2146 # do case-sensitive matching if desired. 2147 if ($dbline[$start] =~ m/$pat/i) { 2148 if ($slave_editor) { 2149 # Handle proper escaping in the slave. 2150 print {$OUT} "\032\032$filename:$start:0\n"; 2151 } 2152 else { 2153 # Just print the line normally. 2154 print {$OUT} "$start:\t",$dbline[$start],"\n"; 2155 } 2156 # And quit since we found something. 2157 last; 2158 } 2159 } 2160 }; 2161 2162 if ($@) { 2163 warn $@; 2164 } 2165 2166 # If we wrapped, there never was a match. 2167 if ( $start == $end ) { 2168 print {$OUT} "/$pat/: not found\n"; 2169 } 2170 next CMD; 2171 } 2172 2173 return; 2174} 2175 2176sub _DB__handle_question_mark_command { 2177 my ($obj) = @_; 2178 2179 # ? - backward pattern search. 2180 if (my ($inpat) = $cmd =~ m#\A\?(.*)\z#) { 2181 2182 # Get the pattern, remove trailing question mark. 2183 $inpat =~ s:([^\\])\?$:$1:; 2184 2185 # If we've got one ... 2186 if ( $inpat ne "" ) { 2187 2188 # Turn off die & warn handlers. 2189 local $SIG{__DIE__}; 2190 local $SIG{__WARN__}; 2191 eval '$inpat =~ m' . "\a$inpat\a"; 2192 2193 if ( $@ ne "" ) { 2194 2195 # Ouch. Not good. Print the error. 2196 print $OUT $@; 2197 next CMD; 2198 } 2199 $obj->pat($inpat); 2200 } ## end if ($inpat ne "") 2201 2202 # Where we are now is where to stop after wraparound. 2203 $end = $start; 2204 2205 # Don't move away from this line. 2206 $incr = -1; 2207 2208 my $pat = $obj->pat; 2209 # Search inside the eval to prevent pattern badness 2210 # from killing us. 2211 eval { 2212 no strict q/vars/; 2213 for (;;) { 2214 # Back up a line. 2215 --$start; 2216 2217 # Wrap if we pass the first line. 2218 2219 $start = $max if ($start <= 0); 2220 2221 # Quit if we get back where we started, 2222 last if ($start == $end); 2223 2224 # Match? 2225 if ($dbline[$start] =~ m/$pat/i) { 2226 if ($slave_editor) { 2227 # Yep, follow slave editor requirements. 2228 print $OUT "\032\032$filename:$start:0\n"; 2229 } 2230 else { 2231 # Yep, just print normally. 2232 print $OUT "$start:\t",$dbline[$start],"\n"; 2233 } 2234 2235 # Found, so done. 2236 last; 2237 } 2238 } 2239 }; 2240 2241 # Say we failed if the loop never found anything, 2242 if ( $start == $end ) { 2243 print {$OUT} "?$pat?: not found\n"; 2244 } 2245 next CMD; 2246 } 2247 2248 return; 2249} 2250 2251sub _DB__handle_restart_and_rerun_commands { 2252 my ($obj) = @_; 2253 2254 my $cmd_cmd = $obj->cmd_verb; 2255 my $cmd_params = $obj->cmd_args; 2256 # R - restart execution. 2257 # rerun - controlled restart execution. 2258 if ($cmd_cmd eq 'rerun' or $cmd_params eq '') { 2259 my @args = ($cmd_cmd eq 'R' ? restart() : rerun($cmd_params)); 2260 2261 # Close all non-system fds for a clean restart. A more 2262 # correct method would be to close all fds that were not 2263 # open when the process started, but this seems to be 2264 # hard. See "debugger 'R'estart and open database 2265 # connections" on p5p. 2266 2267 my $max_fd = 1024; # default if POSIX can't be loaded 2268 if (eval { require POSIX }) { 2269 eval { $max_fd = POSIX::sysconf(POSIX::_SC_OPEN_MAX()) }; 2270 } 2271 2272 if (defined $max_fd) { 2273 foreach ($^F+1 .. $max_fd-1) { 2274 next unless open FD_TO_CLOSE, "<&=$_"; 2275 close(FD_TO_CLOSE); 2276 } 2277 } 2278 2279 # And run Perl again. We use exec() to keep the 2280 # PID stable (and that way $ini_pids is still valid). 2281 exec(@args) or print {$OUT} "exec failed: $!\n"; 2282 2283 last CMD; 2284 } 2285 2286 return; 2287} 2288 2289sub _DB__handle_run_command_in_pager_command { 2290 my ($obj) = @_; 2291 2292 if ($cmd =~ m#\A\|\|?\s*[^|]#) { 2293 if ( $pager =~ /^\|/ ) { 2294 2295 # Default pager is into a pipe. Redirect I/O. 2296 open( SAVEOUT, ">&STDOUT" ) 2297 || _db_warn("Can't save STDOUT"); 2298 open( STDOUT, ">&OUT" ) 2299 || _db_warn("Can't redirect STDOUT"); 2300 } ## end if ($pager =~ /^\|/) 2301 else { 2302 2303 # Not into a pipe. STDOUT is safe. 2304 open( SAVEOUT, ">&OUT" ) || _db_warn("Can't save DB::OUT"); 2305 } 2306 2307 # Fix up environment to record we have less if so. 2308 fix_less(); 2309 2310 unless ( $obj->piped(scalar ( open( OUT, $pager ) ) ) ) { 2311 2312 # Couldn't open pipe to pager. 2313 _db_warn("Can't pipe output to '$pager'"); 2314 if ( $pager =~ /^\|/ ) { 2315 2316 # Redirect I/O back again. 2317 open( OUT, ">&STDOUT" ) # XXX: lost message 2318 || _db_warn("Can't restore DB::OUT"); 2319 open( STDOUT, ">&SAVEOUT" ) 2320 || _db_warn("Can't restore STDOUT"); 2321 close(SAVEOUT); 2322 } ## end if ($pager =~ /^\|/) 2323 else { 2324 2325 # Redirect I/O. STDOUT already safe. 2326 open( OUT, ">&STDOUT" ) # XXX: lost message 2327 || _db_warn("Can't restore DB::OUT"); 2328 } 2329 next CMD; 2330 } ## end unless ($piped = open(OUT,... 2331 2332 # Set up broken-pipe handler if necessary. 2333 $SIG{PIPE} = \&DB::catch 2334 if $pager =~ /^\|/ 2335 && ( "" eq $SIG{PIPE} || "DEFAULT" eq $SIG{PIPE} ); 2336 2337 _autoflush(\*OUT); 2338 # Save current filehandle, and put it back. 2339 $obj->selected(scalar( select(OUT) )); 2340 # Don't put it back if pager was a pipe. 2341 if ($cmd !~ /\A\|\|/) 2342 { 2343 select($obj->selected()); 2344 $obj->selected(""); 2345 } 2346 2347 # Trim off the pipe symbols and run the command now. 2348 $cmd =~ s#\A\|+\s*##; 2349 redo PIPE; 2350 } 2351 2352 return; 2353} 2354 2355sub _DB__handle_m_command { 2356 my ($obj) = @_; 2357 2358 if ($cmd =~ s#\Am\s+([\w:]+)\s*\z# #) { 2359 methods($1); 2360 next CMD; 2361 } 2362 2363 # m expr - set up DB::eval to do the work 2364 if ($cmd =~ s#\Am\b# #) { # Rest gets done by DB::eval() 2365 $onetimeDump = 'methods'; # method output gets used there 2366 } 2367 2368 return; 2369} 2370 2371sub _DB__at_end_of_every_command { 2372 my ($obj) = @_; 2373 2374 # At the end of every command: 2375 if ($obj->piped) { 2376 2377 # Unhook the pipe mechanism now. 2378 if ( $pager =~ /^\|/ ) { 2379 2380 # No error from the child. 2381 $? = 0; 2382 2383 # we cannot warn here: the handle is missing --tchrist 2384 close(OUT) || print SAVEOUT "\nCan't close DB::OUT\n"; 2385 2386 # most of the $? crud was coping with broken cshisms 2387 # $? is explicitly set to 0, so this never runs. 2388 if ($?) { 2389 print SAVEOUT "Pager '$pager' failed: "; 2390 if ( $? == -1 ) { 2391 print SAVEOUT "shell returned -1\n"; 2392 } 2393 elsif ( $? >> 8 ) { 2394 print SAVEOUT ( $? & 127 ) 2395 ? " (SIG#" . ( $? & 127 ) . ")" 2396 : "", ( $? & 128 ) ? " -- core dumped" : "", "\n"; 2397 } 2398 else { 2399 print SAVEOUT "status ", ( $? >> 8 ), "\n"; 2400 } 2401 } ## end if ($?) 2402 2403 # Reopen filehandle for our output (if we can) and 2404 # restore STDOUT (if we can). 2405 open( OUT, ">&STDOUT" ) || _db_warn("Can't restore DB::OUT"); 2406 open( STDOUT, ">&SAVEOUT" ) 2407 || _db_warn("Can't restore STDOUT"); 2408 2409 # Turn off pipe exception handler if necessary. 2410 $SIG{PIPE} = "DEFAULT" if $SIG{PIPE} eq \&DB::catch; 2411 2412 # Will stop ignoring SIGPIPE if done like nohup(1) 2413 # does SIGINT but Perl doesn't give us a choice. 2414 } ## end if ($pager =~ /^\|/) 2415 else { 2416 2417 # Non-piped "pager". Just restore STDOUT. 2418 open( OUT, ">&SAVEOUT" ) || _db_warn("Can't restore DB::OUT"); 2419 } 2420 2421 # Close filehandle pager was using, restore the normal one 2422 # if necessary, 2423 close(SAVEOUT); 2424 2425 if ($obj->selected() ne "") { 2426 select($obj->selected); 2427 $obj->selected(""); 2428 } 2429 2430 # No pipes now. 2431 $obj->piped(""); 2432 } ## end if ($piped) 2433 2434 return; 2435} 2436 2437sub _DB__handle_watch_expressions 2438{ 2439 my $self = shift; 2440 2441 if ( $DB::trace & 2 ) { 2442 for my $n (0 .. $#DB::to_watch) { 2443 $DB::evalarg = $DB::to_watch[$n]; 2444 local $DB::onetimeDump; # Tell DB::eval() to not output results 2445 2446 # Fix context DB::eval() wants to return an array, but 2447 # we need a scalar here. 2448 my ($val) = join( "', '", DB::eval(@_) ); 2449 $val = ( ( defined $val ) ? "'$val'" : 'undef' ); 2450 2451 # Did it change? 2452 if ( $val ne $DB::old_watch[$n] ) { 2453 2454 # Yep! Show the difference, and fake an interrupt. 2455 $DB::signal = 1; 2456 print {$DB::OUT} <<EOP; 2457Watchpoint $n:\t$DB::to_watch[$n] changed: 2458 old value:\t$DB::old_watch[$n] 2459 new value:\t$val 2460EOP 2461 $DB::old_watch[$n] = $val; 2462 } ## end if ($val ne $old_watch... 2463 } ## end for my $n (0 .. 2464 } ## end if ($trace & 2) 2465 2466 return; 2467} 2468 2469# 't' is type. 2470# 'm' is method. 2471# 'v' is the value (i.e: method name or subroutine ref). 2472# 's' is subroutine. 2473my %cmd_lookup = 2474( 2475 '-' => { t => 'm', v => '_handle_dash_command', }, 2476 '.' => { t => 's', v => \&_DB__handle_dot_command, }, 2477 '=' => { t => 'm', v => '_handle_equal_sign_command', }, 2478 'H' => { t => 'm', v => '_handle_H_command', }, 2479 'S' => { t => 'm', v => '_handle_S_command', }, 2480 'T' => { t => 'm', v => '_handle_T_command', }, 2481 'W' => { t => 'm', v => '_handle_W_command', }, 2482 'c' => { t => 's', v => \&_DB__handle_c_command, }, 2483 'f' => { t => 's', v => \&_DB__handle_f_command, }, 2484 'm' => { t => 's', v => \&_DB__handle_m_command, }, 2485 'n' => { t => 'm', v => '_handle_n_command', }, 2486 'p' => { t => 'm', v => '_handle_p_command', }, 2487 'q' => { t => 'm', v => '_handle_q_command', }, 2488 'r' => { t => 'm', v => '_handle_r_command', }, 2489 's' => { t => 'm', v => '_handle_s_command', }, 2490 'save' => { t => 'm', v => '_handle_save_command', }, 2491 'source' => { t => 'm', v => '_handle_source_command', }, 2492 't' => { t => 'm', v => '_handle_t_command', }, 2493 'w' => { t => 'm', v => '_handle_w_command', }, 2494 'x' => { t => 'm', v => '_handle_x_command', }, 2495 'y' => { t => 's', v => \&_DB__handle_y_command, }, 2496 (map { $_ => { t => 'm', v => '_handle_V_command_and_X_command', }, } 2497 ('X', 'V')), 2498 (map { $_ => { t => 'm', v => '_handle_enable_disable_commands', }, } 2499 qw(enable disable)), 2500 (map { $_ => 2501 { t => 's', v => \&_DB__handle_restart_and_rerun_commands, }, 2502 } qw(R rerun)), 2503 (map { $_ => {t => 'm', v => '_handle_cmd_wrapper_commands' }, } 2504 qw(a A b B e E h i l L M o O P v w W)), 2505); 2506 2507sub DB { 2508 2509 # lock the debugger and get the thread id for the prompt 2510 lock($DBGR); 2511 my $tid; 2512 my $position; 2513 my ($prefix, $after, $infix); 2514 my $pat; 2515 my $explicit_stop; 2516 my $piped; 2517 my $selected; 2518 2519 if ($ENV{PERL5DB_THREADED}) { 2520 $tid = eval { "[".threads->tid."]" }; 2521 } 2522 2523 my $cmd_verb; 2524 my $cmd_args; 2525 2526 my $obj = DB::Obj->new( 2527 { 2528 position => \$position, 2529 prefix => \$prefix, 2530 after => \$after, 2531 explicit_stop => \$explicit_stop, 2532 infix => \$infix, 2533 cmd_args => \$cmd_args, 2534 cmd_verb => \$cmd_verb, 2535 pat => \$pat, 2536 piped => \$piped, 2537 selected => \$selected, 2538 }, 2539 ); 2540 2541 $obj->_DB_on_init__initialize_globals(@_); 2542 2543 # Preserve current values of $@, $!, $^E, $,, $/, $\, $^W. 2544 # The code being debugged may have altered them. 2545 DB::save(); 2546 2547 # Since DB::DB gets called after every line, we can use caller() to 2548 # figure out where we last were executing. Sneaky, eh? This works because 2549 # caller is returning all the extra information when called from the 2550 # debugger. 2551 local ( $package, $filename, $line ) = caller; 2552 $filename_ini = $filename; 2553 2554 # set up the context for DB::eval, so it can properly execute 2555 # code on behalf of the user. We add the package in so that the 2556 # code is eval'ed in the proper package (not in the debugger!). 2557 local $usercontext = _calc_usercontext($package); 2558 2559 # Create an alias to the active file magical array to simplify 2560 # the code here. 2561 local (*dbline) = $main::{ '_<' . $filename }; 2562 2563 # Last line in the program. 2564 $max = $#dbline; 2565 2566 # The &-call is here to ascertain the mutability of @_. 2567 &_DB__determine_if_we_should_break; 2568 2569 # Preserve the current stop-or-not, and see if any of the W 2570 # (watch expressions) has changed. 2571 my $was_signal = $signal; 2572 2573 # If we have any watch expressions ... 2574 _DB__handle_watch_expressions($obj); 2575 2576=head2 C<watchfunction()> 2577 2578C<watchfunction()> is a function that can be defined by the user; it is a 2579function which will be run on each entry to C<DB::DB>; it gets the 2580current package, filename, and line as its parameters. 2581 2582The watchfunction can do anything it likes; it is executing in the 2583debugger's context, so it has access to all of the debugger's internal 2584data structures and functions. 2585 2586C<watchfunction()> can control the debugger's actions. Any of the following 2587will cause the debugger to return control to the user's program after 2588C<watchfunction()> executes: 2589 2590=over 4 2591 2592=item * 2593 2594Returning a false value from the C<watchfunction()> itself. 2595 2596=item * 2597 2598Altering C<$single> to a false value. 2599 2600=item * 2601 2602Altering C<$signal> to a false value. 2603 2604=item * 2605 2606Turning off the C<4> bit in C<$trace> (this also disables the 2607check for C<watchfunction()>. This can be done with 2608 2609 $trace &= ~4; 2610 2611=back 2612 2613=cut 2614 2615 # If there's a user-defined DB::watchfunction, call it with the 2616 # current package, filename, and line. The function executes in 2617 # the DB:: package. 2618 if ( $trace & 4 ) { # User-installed watch 2619 return 2620 if watchfunction( $package, $filename, $line ) 2621 and not $single 2622 and not $was_signal 2623 and not( $trace & ~4 ); 2624 } ## end if ($trace & 4) 2625 2626 # Pick up any alteration to $signal in the watchfunction, and 2627 # turn off the signal now. 2628 $was_signal = $signal; 2629 $signal = 0; 2630 2631=head2 GETTING READY TO EXECUTE COMMANDS 2632 2633The debugger decides to take control if single-step mode is on, the 2634C<t> command was entered, or the user generated a signal. If the program 2635has fallen off the end, we set things up so that entering further commands 2636won't cause trouble, and we say that the program is over. 2637 2638=cut 2639 2640 # Make sure that we always print if asked for explicitly regardless 2641 # of $trace_to_depth . 2642 $explicit_stop = ($single || $was_signal); 2643 2644 # Check to see if we should grab control ($single true, 2645 # trace set appropriately, or we got a signal). 2646 if ( $explicit_stop || ( $trace & 1 ) ) { 2647 $obj->_DB__grab_control(@_); 2648 } ## end if ($single || ($trace... 2649 2650=pod 2651 2652If there's an action to be executed for the line we stopped at, execute it. 2653If there are any preprompt actions, execute those as well. 2654 2655=cut 2656 2657 # If there's an action, do it now. 2658 if ($action) { 2659 $evalarg = $action; 2660 # The &-call is here to ascertain the mutability of @_. 2661 &DB::eval; 2662 } 2663 2664 # Are we nested another level (e.g., did we evaluate a function 2665 # that had a breakpoint in it at the debugger prompt)? 2666 if ( $single || $was_signal ) { 2667 2668 # Yes, go down a level. 2669 local $level = $level + 1; 2670 2671 # Do any pre-prompt actions. 2672 foreach $evalarg (@$pre) { 2673 # The &-call is here to ascertain the mutability of @_. 2674 &DB::eval; 2675 } 2676 2677 # Complain about too much recursion if we passed the limit. 2678 if ($single & 4) { 2679 print $OUT $stack_depth . " levels deep in subroutine calls!\n"; 2680 } 2681 2682 # The line we're currently on. Set $incr to -1 to stay here 2683 # until we get a command that tells us to advance. 2684 $start = $line; 2685 $incr = -1; # for backward motion. 2686 2687 # Tack preprompt debugger actions ahead of any actual input. 2688 @typeahead = ( @$pretype, @typeahead ); 2689 2690=head2 WHERE ARE WE? 2691 2692XXX Relocate this section? 2693 2694The debugger normally shows the line corresponding to the current line of 2695execution. Sometimes, though, we want to see the next line, or to move elsewhere 2696in the file. This is done via the C<$incr>, C<$start>, and C<$max> variables. 2697 2698C<$incr> controls by how many lines the I<current> line should move forward 2699after a command is executed. If set to -1, this indicates that the I<current> 2700line shouldn't change. 2701 2702C<$start> is the I<current> line. It is used for things like knowing where to 2703move forwards or backwards from when doing an C<L> or C<-> command. 2704 2705C<$max> tells the debugger where the last line of the current file is. It's 2706used to terminate loops most often. 2707 2708=head2 THE COMMAND LOOP 2709 2710Most of C<DB::DB> is actually a command parsing and dispatch loop. It comes 2711in two parts: 2712 2713=over 4 2714 2715=item * 2716 2717The outer part of the loop, starting at the C<CMD> label. This loop 2718reads a command and then executes it. 2719 2720=item * 2721 2722The inner part of the loop, starting at the C<PIPE> label. This part 2723is wholly contained inside the C<CMD> block and only executes a command. 2724Used to handle commands running inside a pager. 2725 2726=back 2727 2728So why have two labels to restart the loop? Because sometimes, it's easier to 2729have a command I<generate> another command and then re-execute the loop to do 2730the new command. This is faster, but perhaps a bit more convoluted. 2731 2732=cut 2733 2734 # The big command dispatch loop. It keeps running until the 2735 # user yields up control again. 2736 # 2737 # If we have a terminal for input, and we get something back 2738 # from readline(), keep on processing. 2739 2740 CMD: 2741 while (_DB__read_next_cmd($tid)) 2742 { 2743 2744 share($cmd); 2745 # ... try to execute the input as debugger commands. 2746 2747 # Don't stop running. 2748 $single = 0; 2749 2750 # No signal is active. 2751 $signal = 0; 2752 2753 # Handle continued commands (ending with \): 2754 if ($cmd =~ s/\\\z/\n/) { 2755 $cmd .= DB::readline(" cont: "); 2756 redo CMD; 2757 } 2758 2759=head4 The null command 2760 2761A newline entered by itself means I<re-execute the last command>. We grab the 2762command out of C<$laststep> (where it was recorded previously), and copy it 2763back into C<$cmd> to be executed below. If there wasn't any previous command, 2764we'll do nothing below (no command will match). If there was, we also save it 2765in the command history and fall through to allow the command parsing to pick 2766it up. 2767 2768=cut 2769 2770 # Empty input means repeat the last command. 2771 if ($cmd eq '') { 2772 $cmd = $laststep; 2773 } 2774 chomp($cmd); # get rid of the annoying extra newline 2775 if (length($cmd) >= 2) { 2776 push( @hist, $cmd ); 2777 } 2778 push( @truehist, $cmd ); 2779 share(@hist); 2780 share(@truehist); 2781 2782 # This is a restart point for commands that didn't arrive 2783 # via direct user input. It allows us to 'redo PIPE' to 2784 # re-execute command processing without reading a new command. 2785 PIPE: { 2786 _DB__trim_command_and_return_first_component($obj); 2787 2788=head3 COMMAND ALIASES 2789 2790The debugger can create aliases for commands (these are stored in the 2791C<%alias> hash). Before a command is executed, the command loop looks it up 2792in the alias hash and substitutes the contents of the alias for the command, 2793completely replacing it. 2794 2795=cut 2796 2797 # See if there's an alias for the command, and set it up if so. 2798 if ( $alias{$cmd_verb} ) { 2799 2800 # Squelch signal handling; we want to keep control here 2801 # if something goes loco during the alias eval. 2802 local $SIG{__DIE__}; 2803 local $SIG{__WARN__}; 2804 2805 # This is a command, so we eval it in the DEBUGGER's 2806 # scope! Otherwise, we can't see the special debugger 2807 # variables, or get to the debugger's subs. (Well, we 2808 # _could_, but why make it even more complicated?) 2809 eval "\$cmd =~ $alias{$cmd_verb}"; 2810 if ($@) { 2811 local $\ = ''; 2812 print $OUT "Couldn't evaluate '$cmd_verb' alias: $@"; 2813 next CMD; 2814 } 2815 _DB__trim_command_and_return_first_component($obj); 2816 } ## end if ($alias{$cmd_verb}) 2817 2818=head3 MAIN-LINE COMMANDS 2819 2820All of these commands work up to and after the program being debugged has 2821terminated. 2822 2823=head4 C<q> - quit 2824 2825Quit the debugger. This entails setting the C<$fall_off_end> flag, so we don't 2826try to execute further, cleaning any restart-related stuff out of the 2827environment, and executing with the last value of C<$?>. 2828 2829=cut 2830 2831 # All of these commands were remapped in perl 5.8.0; 2832 # we send them off to the secondary dispatcher (see below). 2833 $obj->_handle_special_char_cmd_wrapper_commands; 2834 _DB__trim_command_and_return_first_component($obj); 2835 2836 if (my $cmd_rec = $cmd_lookup{$cmd_verb}) { 2837 my $type = $cmd_rec->{t}; 2838 my $val = $cmd_rec->{v}; 2839 if ($type eq 'm') { 2840 $obj->$val(); 2841 } 2842 elsif ($type eq 's') { 2843 $val->($obj); 2844 } 2845 } 2846 2847=head4 C<t> - trace [n] 2848 2849Turn tracing on or off. Inverts the appropriate bit in C<$trace> (q.v.). 2850If level is specified, set C<$trace_to_depth>. 2851 2852=head4 C<S> - list subroutines matching/not matching a pattern 2853 2854Walks through C<%sub>, checking to see whether or not to print the name. 2855 2856=head4 C<X> - list variables in current package 2857 2858Since the C<V> command actually processes this, just change this to the 2859appropriate C<V> command and fall through. 2860 2861=head4 C<V> - list variables 2862 2863Uses C<dumpvar.pl> to dump out the current values for selected variables. 2864 2865=head4 C<x> - evaluate and print an expression 2866 2867Hands the expression off to C<DB::eval>, setting it up to print the value 2868via C<dumpvar.pl> instead of just printing it directly. 2869 2870=head4 C<m> - print methods 2871 2872Just uses C<DB::methods> to determine what methods are available. 2873 2874=head4 C<f> - switch files 2875 2876Switch to a different filename. 2877 2878=head4 C<.> - return to last-executed line. 2879 2880We set C<$incr> to -1 to indicate that the debugger shouldn't move ahead, 2881and then we look up the line in the magical C<%dbline> hash. 2882 2883=head4 C<-> - back one window 2884 2885We change C<$start> to be one window back; if we go back past the first line, 2886we set it to be the first line. We ser C<$incr> to put us back at the 2887currently-executing line, and then put a C<l $start +> (list one window from 2888C<$start>) in C<$cmd> to be executed later. 2889 2890=head3 PRE-580 COMMANDS VS. NEW COMMANDS: C<a, A, b, B, h, l, L, M, o, O, P, v, w, W, E<lt>, E<lt>E<lt>, E<0x7B>, E<0x7B>E<0x7B>> 2891 2892In Perl 5.8.0, a realignment of the commands was done to fix up a number of 2893problems, most notably that the default case of several commands destroying 2894the user's work in setting watchpoints, actions, etc. We wanted, however, to 2895retain the old commands for those who were used to using them or who preferred 2896them. At this point, we check for the new commands and call C<cmd_wrapper> to 2897deal with them instead of processing them in-line. 2898 2899=head4 C<y> - List lexicals in higher scope 2900 2901Uses C<PadWalker> to find the lexicals supplied as arguments in a scope 2902above the current one and then displays then using C<dumpvar.pl>. 2903 2904=head3 COMMANDS NOT WORKING AFTER PROGRAM ENDS 2905 2906All of the commands below this point don't work after the program being 2907debugged has ended. All of them check to see if the program has ended; this 2908allows the commands to be relocated without worrying about a 'line of 2909demarcation' above which commands can be entered anytime, and below which 2910they can't. 2911 2912=head4 C<n> - single step, but don't trace down into subs 2913 2914Done by setting C<$single> to 2, which forces subs to execute straight through 2915when entered (see C<DB::sub>). We also save the C<n> command in C<$laststep>, 2916so a null command knows what to re-execute. 2917 2918=head4 C<s> - single-step, entering subs 2919 2920Sets C<$single> to 1, which causes C<DB::sub> to continue tracing inside 2921subs. Also saves C<s> as C<$lastcmd>. 2922 2923=head4 C<c> - run continuously, setting an optional breakpoint 2924 2925Most of the code for this command is taken up with locating the optional 2926breakpoint, which is either a subroutine name or a line number. We set 2927the appropriate one-time-break in C<@dbline> and then turn off single-stepping 2928in this and all call levels above this one. 2929 2930=head4 C<r> - return from a subroutine 2931 2932For C<r> to work properly, the debugger has to stop execution again 2933immediately after the return is executed. This is done by forcing 2934single-stepping to be on in the call level above the current one. If 2935we are printing return values when a C<r> is executed, set C<$doret> 2936appropriately, and force us out of the command loop. 2937 2938=head4 C<T> - stack trace 2939 2940Just calls C<DB::print_trace>. 2941 2942=head4 C<w> - List window around current line. 2943 2944Just calls C<DB::cmd_w>. 2945 2946=head4 C<W> - watch-expression processing. 2947 2948Just calls C<DB::cmd_W>. 2949 2950=head4 C</> - search forward for a string in the source 2951 2952We take the argument and treat it as a pattern. If it turns out to be a 2953bad one, we return the error we got from trying to C<eval> it and exit. 2954If not, we create some code to do the search and C<eval> it so it can't 2955mess us up. 2956 2957=cut 2958 2959 _DB__handle_forward_slash_command($obj); 2960 2961=head4 C<?> - search backward for a string in the source 2962 2963Same as for C</>, except the loop runs backwards. 2964 2965=cut 2966 2967 _DB__handle_question_mark_command($obj); 2968 2969=head4 C<$rc> - Recall command 2970 2971Manages the commands in C<@hist> (which is created if C<Term::ReadLine> reports 2972that the terminal supports history). It find the command required, puts it 2973into C<$cmd>, and redoes the loop to execute it. 2974 2975=cut 2976 2977 # $rc - recall command. 2978 $obj->_handle_rc_recall_command; 2979 2980=head4 C<$sh$sh> - C<system()> command 2981 2982Calls the C<_db_system()> to handle the command. This keeps the C<STDIN> and 2983C<STDOUT> from getting messed up. 2984 2985=cut 2986 2987 $obj->_handle_sh_command; 2988 2989=head4 C<$rc I<pattern> $rc> - Search command history 2990 2991Another command to manipulate C<@hist>: this one searches it with a pattern. 2992If a command is found, it is placed in C<$cmd> and executed via C<redo>. 2993 2994=cut 2995 2996 $obj->_handle_rc_search_history_command; 2997 2998=head4 C<$sh> - Invoke a shell 2999 3000Uses C<_db_system()> to invoke a shell. 3001 3002=cut 3003 3004=head4 C<$sh I<command>> - Force execution of a command in a shell 3005 3006Like the above, but the command is passed to the shell. Again, we use 3007C<_db_system()> to avoid problems with C<STDIN> and C<STDOUT>. 3008 3009=head4 C<H> - display commands in history 3010 3011Prints the contents of C<@hist> (if any). 3012 3013=head4 C<man, doc, perldoc> - look up documentation 3014 3015Just calls C<runman()> to print the appropriate document. 3016 3017=cut 3018 3019 $obj->_handle_doc_command; 3020 3021=head4 C<p> - print 3022 3023Builds a C<print EXPR> expression in the C<$cmd>; this will get executed at 3024the bottom of the loop. 3025 3026=head4 C<=> - define command alias 3027 3028Manipulates C<%alias> to add or list command aliases. 3029 3030=head4 C<source> - read commands from a file. 3031 3032Opens a lexical filehandle and stacks it on C<@cmdfhs>; C<DB::readline> will 3033pick it up. 3034 3035=head4 C<enable> C<disable> - enable or disable breakpoints 3036 3037This enables or disables breakpoints. 3038 3039=head4 C<save> - send current history to a file 3040 3041Takes the complete history, (not the shrunken version you see with C<H>), 3042and saves it to the given filename, so it can be replayed using C<source>. 3043 3044Note that all C<^(save|source)>'s are commented out with a view to minimise recursion. 3045 3046=head4 C<R> - restart 3047 3048Restart the debugger session. 3049 3050=head4 C<rerun> - rerun the current session 3051 3052Return to any given position in the B<true>-history list 3053 3054=head4 C<|, ||> - pipe output through the pager. 3055 3056For C<|>, we save C<OUT> (the debugger's output filehandle) and C<STDOUT> 3057(the program's standard output). For C<||>, we only save C<OUT>. We open a 3058pipe to the pager (restoring the output filehandles if this fails). If this 3059is the C<|> command, we also set up a C<SIGPIPE> handler which will simply 3060set C<$signal>, sending us back into the debugger. 3061 3062We then trim off the pipe symbols and C<redo> the command loop at the 3063C<PIPE> label, causing us to evaluate the command in C<$cmd> without 3064reading another. 3065 3066=cut 3067 3068 # || - run command in the pager, with output to DB::OUT. 3069 _DB__handle_run_command_in_pager_command($obj); 3070 3071=head3 END OF COMMAND PARSING 3072 3073Anything left in C<$cmd> at this point is a Perl expression that we want to 3074evaluate. We'll always evaluate in the user's context, and fully qualify 3075any variables we might want to address in the C<DB> package. 3076 3077=cut 3078 3079 } # PIPE: 3080 3081 # trace an expression 3082 $cmd =~ s/^t\s/\$DB::trace |= 1;\n/; 3083 3084 # Make sure the flag that says "the debugger's running" is 3085 # still on, to make sure we get control again. 3086 $evalarg = "\$^D = \$^D | \$DB::db_stop;\n$cmd"; 3087 3088 # Run *our* eval that executes in the caller's context. 3089 # The &-call is here to ascertain the mutability of @_. 3090 &DB::eval; 3091 3092 # Turn off the one-time-dump stuff now. 3093 if ($onetimeDump) { 3094 $onetimeDump = undef; 3095 $onetimedumpDepth = undef; 3096 } 3097 elsif ( $term_pid == $$ ) { 3098 eval { # May run under miniperl, when not available... 3099 STDOUT->flush(); 3100 STDERR->flush(); 3101 }; 3102 3103 # XXX If this is the master pid, print a newline. 3104 print {$OUT} "\n"; 3105 } 3106 } ## end while (($term || &setterm... 3107 3108=head3 POST-COMMAND PROCESSING 3109 3110After each command, we check to see if the command output was piped anywhere. 3111If so, we go through the necessary code to unhook the pipe and go back to 3112our standard filehandles for input and output. 3113 3114=cut 3115 3116 continue { # CMD: 3117 _DB__at_end_of_every_command($obj); 3118 } # CMD: 3119 3120=head3 COMMAND LOOP TERMINATION 3121 3122When commands have finished executing, we come here. If the user closed the 3123input filehandle, we turn on C<$fall_off_end> to emulate a C<q> command. We 3124evaluate any post-prompt items. We restore C<$@>, C<$!>, C<$^E>, C<$,>, C<$/>, 3125C<$\>, and C<$^W>, and return a null list as expected by the Perl interpreter. 3126The interpreter will then execute the next line and then return control to us 3127again. 3128 3129=cut 3130 3131 # No more commands? Quit. 3132 $fall_off_end = 1 unless defined $cmd; # Emulate 'q' on EOF 3133 3134 # Evaluate post-prompt commands. 3135 foreach $evalarg (@$post) { 3136 # The &-call is here to ascertain the mutability of @_. 3137 &DB::eval; 3138 } 3139 } # if ($single || $signal) 3140 3141 # Put the user's globals back where you found them. 3142 ( $@, $!, $^E, $,, $/, $\, $^W ) = @saved; 3143 (); 3144} ## end sub DB 3145 3146# Because DB::Obj is used above, 3147# 3148# my $obj = DB::Obj->new( 3149# 3150# The following package declaraton must come before that, 3151# or else runtime errors will occur with 3152# 3153# PERLDB_OPTS="autotrace nonstop" 3154# 3155# ( rt#116771 ) 3156BEGIN { 3157 3158package DB::Obj; 3159 3160sub new { 3161 my $class = shift; 3162 3163 my $self = bless {}, $class; 3164 3165 $self->_init(@_); 3166 3167 return $self; 3168} 3169 3170sub _init { 3171 my ($self, $args) = @_; 3172 3173 %{$self} = (%$self, %$args); 3174 3175 return; 3176} 3177 3178{ 3179 no strict 'refs'; 3180 foreach my $slot_name (qw( 3181 after explicit_stop infix pat piped position prefix selected cmd_verb 3182 cmd_args 3183 )) { 3184 my $slot = $slot_name; 3185 *{$slot} = sub { 3186 my $self = shift; 3187 3188 if (@_) { 3189 ${ $self->{$slot} } = shift; 3190 } 3191 3192 return ${ $self->{$slot} }; 3193 }; 3194 3195 *{"append_to_$slot"} = sub { 3196 my $self = shift; 3197 my $s = shift; 3198 3199 return $self->$slot($self->$slot . $s); 3200 }; 3201 } 3202} 3203 3204sub _DB_on_init__initialize_globals 3205{ 3206 my $self = shift; 3207 3208 # Check for whether we should be running continuously or not. 3209 # _After_ the perl program is compiled, $single is set to 1: 3210 if ( $single and not $second_time++ ) { 3211 3212 # Options say run non-stop. Run until we get an interrupt. 3213 if ($runnonstop) { # Disable until signal 3214 # If there's any call stack in place, turn off single 3215 # stepping into subs throughout the stack. 3216 for my $i (0 .. $stack_depth) { 3217 $stack[ $i ] &= ~1; 3218 } 3219 3220 # And we are now no longer in single-step mode. 3221 $single = 0; 3222 3223 # If we simply returned at this point, we wouldn't get 3224 # the trace info. Fall on through. 3225 # return; 3226 } ## end if ($runnonstop) 3227 3228 elsif ($ImmediateStop) { 3229 3230 # We are supposed to stop here; XXX probably a break. 3231 $ImmediateStop = 0; # We've processed it; turn it off 3232 $signal = 1; # Simulate an interrupt to force 3233 # us into the command loop 3234 } 3235 } ## end if ($single and not $second_time... 3236 3237 # If we're in single-step mode, or an interrupt (real or fake) 3238 # has occurred, turn off non-stop mode. 3239 $runnonstop = 0 if $single or $signal; 3240 3241 return; 3242} 3243 3244sub _my_print_lineinfo 3245{ 3246 my ($self, $i, $incr_pos) = @_; 3247 3248 if ($frame) { 3249 # Print it indented if tracing is on. 3250 DB::print_lineinfo( ' ' x $stack_depth, 3251 "$i:\t$DB::dbline[$i]" . $self->after ); 3252 } 3253 else { 3254 DB::depth_print_lineinfo($self->explicit_stop, $incr_pos); 3255 } 3256} 3257 3258sub _curr_line { 3259 return $DB::dbline[$line]; 3260} 3261 3262sub _is_full { 3263 my ($self, $letter) = @_; 3264 3265 return ($DB::cmd eq $letter); 3266} 3267 3268sub _DB__grab_control 3269{ 3270 my $self = shift; 3271 3272 # Yes, grab control. 3273 if ($slave_editor) { 3274 3275 # Tell the editor to update its position. 3276 $self->position("\032\032${DB::filename}:$line:0\n"); 3277 DB::print_lineinfo($self->position()); 3278 } 3279 3280=pod 3281 3282Special check: if we're in package C<DB::fake>, we've gone through the 3283C<END> block at least once. We set up everything so that we can continue 3284to enter commands and have a valid context to be in. 3285 3286=cut 3287 3288 elsif ( $DB::package eq 'DB::fake' ) { 3289 3290 # Fallen off the end already. 3291 if (!$DB::term) { 3292 DB::setterm(); 3293 } 3294 3295 DB::print_help(<<EOP); 3296Debugged program terminated. Use B<q> to quit or B<R> to restart, 3297use B<o> I<inhibit_exit> to avoid stopping after program termination, 3298B<h q>, B<h R> or B<h o> to get additional info. 3299EOP 3300 3301 # Set the DB::eval context appropriately. 3302 $DB::package = 'main'; 3303 $DB::usercontext = DB::_calc_usercontext($DB::package); 3304 } ## end elsif ($package eq 'DB::fake') 3305 3306=pod 3307 3308If the program hasn't finished executing, we scan forward to the 3309next executable line, print that out, build the prompt from the file and line 3310number information, and print that. 3311 3312=cut 3313 3314 else { 3315 3316 3317 # Still somewhere in the midst of execution. Set up the 3318 # debugger prompt. 3319 $DB::sub =~ s/\'/::/; # Swap Perl 4 package separators (') to 3320 # Perl 5 ones (sorry, we don't print Klingon 3321 #module names) 3322 3323 $self->prefix($DB::sub =~ /::/ ? "" : ($DB::package . '::')); 3324 $self->append_to_prefix( "$DB::sub(${DB::filename}:" ); 3325 $self->after( $self->_curr_line =~ /\n$/ ? '' : "\n" ); 3326 3327 # Break up the prompt if it's really long. 3328 if ( length($self->prefix()) > 30 ) { 3329 $self->position($self->prefix . "$line):\n$line:\t" . $self->_curr_line . $self->after); 3330 $self->prefix(""); 3331 $self->infix(":\t"); 3332 } 3333 else { 3334 $self->infix("):\t"); 3335 $self->position( 3336 $self->prefix . $line. $self->infix 3337 . $self->_curr_line . $self->after 3338 ); 3339 } 3340 3341 # Print current line info, indenting if necessary. 3342 $self->_my_print_lineinfo($line, $self->position); 3343 3344 my $i; 3345 my $line_i = sub { return $DB::dbline[$i]; }; 3346 3347 # Scan forward, stopping at either the end or the next 3348 # unbreakable line. 3349 for ( $i = $line + 1 ; $i <= $DB::max && $line_i->() == 0 ; ++$i ) 3350 { #{ vi 3351 3352 # Drop out on null statements, block closers, and comments. 3353 last if $line_i->() =~ /^\s*[\;\}\#\n]/; 3354 3355 # Drop out if the user interrupted us. 3356 last if $signal; 3357 3358 # Append a newline if the line doesn't have one. Can happen 3359 # in eval'ed text, for instance. 3360 $self->after( $line_i->() =~ /\n$/ ? '' : "\n" ); 3361 3362 # Next executable line. 3363 my $incr_pos = $self->prefix . $i . $self->infix . $line_i->() 3364 . $self->after; 3365 $self->append_to_position($incr_pos); 3366 $self->_my_print_lineinfo($i, $incr_pos); 3367 } ## end for ($i = $line + 1 ; $i... 3368 } ## end else [ if ($slave_editor) 3369 3370 return; 3371} 3372 3373sub _handle_t_command { 3374 my $self = shift; 3375 3376 my $levels = $self->cmd_args(); 3377 3378 if ((!length($levels)) or ($levels !~ /\D/)) { 3379 $trace ^= 1; 3380 local $\ = ''; 3381 $DB::trace_to_depth = $levels ? $stack_depth + $levels : 1E9; 3382 print {$OUT} "Trace = " 3383 . ( ( $trace & 1 ) 3384 ? ( $levels ? "on (to level $DB::trace_to_depth)" : "on" ) 3385 : "off" ) . "\n"; 3386 next CMD; 3387 } 3388 3389 return; 3390} 3391 3392 3393sub _handle_S_command { 3394 my $self = shift; 3395 3396 if (my ($print_all_subs, $should_reverse, $Spatt) 3397 = $self->cmd_args =~ /\A((!)?(.+))?\z/) { 3398 # $Spatt is the pattern (if any) to use. 3399 # Reverse scan? 3400 my $Srev = defined $should_reverse; 3401 # No args - print all subs. 3402 my $Snocheck = !defined $print_all_subs; 3403 3404 # Need to make these sane here. 3405 local $\ = ''; 3406 local $, = ''; 3407 3408 # Search through the debugger's magical hash of subs. 3409 # If $nocheck is true, just print the sub name. 3410 # Otherwise, check it against the pattern. We then use 3411 # the XOR trick to reverse the condition as required. 3412 foreach $subname ( sort( keys %sub ) ) { 3413 if ( $Snocheck or $Srev ^ ( $subname =~ /$Spatt/ ) ) { 3414 print $OUT $subname, "\n"; 3415 } 3416 } 3417 next CMD; 3418 } 3419 3420 return; 3421} 3422 3423sub _handle_V_command_and_X_command { 3424 my $self = shift; 3425 3426 $DB::cmd =~ s/^X\b/V $DB::package/; 3427 3428 # Bare V commands get the currently-being-debugged package 3429 # added. 3430 if ($self->_is_full('V')) { 3431 $DB::cmd = "V $DB::package"; 3432 } 3433 3434 # V - show variables in package. 3435 if (my ($new_packname, $new_vars_str) = 3436 $DB::cmd =~ /\AV\b\s*(\S+)\s*(.*)/) { 3437 3438 # Save the currently selected filehandle and 3439 # force output to debugger's filehandle (dumpvar 3440 # just does "print" for output). 3441 my $savout = select($OUT); 3442 3443 # Grab package name and variables to dump. 3444 $packname = $new_packname; 3445 my @vars = split( ' ', $new_vars_str ); 3446 3447 # If main::dumpvar isn't here, get it. 3448 do 'dumpvar.pl' || die $@ unless defined &main::dumpvar; 3449 if ( defined &main::dumpvar ) { 3450 3451 # We got it. Turn off subroutine entry/exit messages 3452 # for the moment, along with return values. 3453 local $frame = 0; 3454 local $doret = -2; 3455 3456 # must detect sigpipe failures - not catching 3457 # then will cause the debugger to die. 3458 eval { 3459 main::dumpvar( 3460 $packname, 3461 defined $option{dumpDepth} 3462 ? $option{dumpDepth} 3463 : -1, # assume -1 unless specified 3464 @vars 3465 ); 3466 }; 3467 3468 # The die doesn't need to include the $@, because 3469 # it will automatically get propagated for us. 3470 if ($@) { 3471 die unless $@ =~ /dumpvar print failed/; 3472 } 3473 } ## end if (defined &main::dumpvar) 3474 else { 3475 3476 # Couldn't load dumpvar. 3477 print $OUT "dumpvar.pl not available.\n"; 3478 } 3479 3480 # Restore the output filehandle, and go round again. 3481 select($savout); 3482 next CMD; 3483 } 3484 3485 return; 3486} 3487 3488sub _handle_dash_command { 3489 my $self = shift; 3490 3491 if ($self->_is_full('-')) { 3492 3493 # back up by a window; go to 1 if back too far. 3494 $start -= $incr + $window + 1; 3495 $start = 1 if $start <= 0; 3496 $incr = $window - 1; 3497 3498 # Generate and execute a "l +" command (handled below). 3499 $DB::cmd = 'l ' . ($start) . '+'; 3500 redo CMD; 3501 } 3502 return; 3503} 3504 3505sub _n_or_s_commands_generic { 3506 my ($self, $new_val) = @_; 3507 # n - next 3508 next CMD if DB::_DB__is_finished(); 3509 3510 # Single step, but don't enter subs. 3511 $single = $new_val; 3512 3513 # Save for empty command (repeat last). 3514 $laststep = $DB::cmd; 3515 last CMD; 3516} 3517 3518sub _n_or_s { 3519 my ($self, $letter, $new_val) = @_; 3520 3521 if ($self->_is_full($letter)) { 3522 $self->_n_or_s_commands_generic($new_val); 3523 } 3524 else { 3525 $self->_n_or_s_and_arg_commands_generic($letter, $new_val); 3526 } 3527 3528 return; 3529} 3530 3531sub _handle_n_command { 3532 my $self = shift; 3533 3534 return $self->_n_or_s('n', 2); 3535} 3536 3537sub _handle_s_command { 3538 my $self = shift; 3539 3540 return $self->_n_or_s('s', 1); 3541} 3542 3543sub _handle_r_command { 3544 my $self = shift; 3545 3546 # r - return from the current subroutine. 3547 if ($self->_is_full('r')) { 3548 3549 # Can't do anything if the program's over. 3550 next CMD if DB::_DB__is_finished(); 3551 3552 # Turn on stack trace. 3553 $stack[$stack_depth] |= 1; 3554 3555 # Print return value unless the stack is empty. 3556 $doret = $option{PrintRet} ? $stack_depth - 1 : -2; 3557 last CMD; 3558 } 3559 3560 return; 3561} 3562 3563sub _handle_T_command { 3564 my $self = shift; 3565 3566 if ($self->_is_full('T')) { 3567 DB::print_trace( $OUT, 1 ); # skip DB 3568 next CMD; 3569 } 3570 3571 return; 3572} 3573 3574sub _handle_w_command { 3575 my $self = shift; 3576 3577 DB::cmd_w( 'w', $self->cmd_args() ); 3578 next CMD; 3579 3580 return; 3581} 3582 3583sub _handle_W_command { 3584 my $self = shift; 3585 3586 if (my $arg = $self->cmd_args) { 3587 DB::cmd_W( 'W', $arg ); 3588 next CMD; 3589 } 3590 3591 return; 3592} 3593 3594sub _handle_rc_recall_command { 3595 my $self = shift; 3596 3597 # $rc - recall command. 3598 if (my ($minus, $arg) = $DB::cmd =~ m#\A$rc+\s*(-)?(\d+)?\z#) { 3599 3600 # No arguments, take one thing off history. 3601 pop(@hist) if length($DB::cmd) > 1; 3602 3603 # Relative (- found)? 3604 # Y - index back from most recent (by 1 if bare minus) 3605 # N - go to that particular command slot or the last 3606 # thing if nothing following. 3607 3608 $self->cmd_verb( 3609 scalar($minus ? ( $#hist - ( $arg || 1 ) ) : ( $arg || $#hist )) 3610 ); 3611 3612 # Pick out the command desired. 3613 $DB::cmd = $hist[$self->cmd_verb]; 3614 3615 # Print the command to be executed and restart the loop 3616 # with that command in the buffer. 3617 print {$OUT} $DB::cmd, "\n"; 3618 redo CMD; 3619 } 3620 3621 return; 3622} 3623 3624sub _handle_rc_search_history_command { 3625 my $self = shift; 3626 3627 # $rc pattern $rc - find a command in the history. 3628 if (my ($arg) = $DB::cmd =~ /\A$rc([^$rc].*)\z/) { 3629 3630 # Create the pattern to use. 3631 my $pat = "^$arg"; 3632 $self->pat($pat); 3633 3634 # Toss off last entry if length is >1 (and it always is). 3635 pop(@hist) if length($DB::cmd) > 1; 3636 3637 my $i; 3638 3639 # Look backward through the history. 3640 SEARCH_HIST: 3641 for ( $i = $#hist ; $i ; --$i ) { 3642 # Stop if we find it. 3643 last SEARCH_HIST if $hist[$i] =~ /$pat/; 3644 } 3645 3646 if ( !$i ) { 3647 3648 # Never found it. 3649 print $OUT "No such command!\n\n"; 3650 next CMD; 3651 } 3652 3653 # Found it. Put it in the buffer, print it, and process it. 3654 $DB::cmd = $hist[$i]; 3655 print $OUT $DB::cmd, "\n"; 3656 redo CMD; 3657 } 3658 3659 return; 3660} 3661 3662sub _handle_H_command { 3663 my $self = shift; 3664 3665 if ($self->cmd_args =~ m#\A\*#) { 3666 @hist = @truehist = (); 3667 print $OUT "History cleansed\n"; 3668 next CMD; 3669 } 3670 3671 if (my ($num) = $self->cmd_args =~ /\A(?:-(\d+))?/) { 3672 3673 # Anything other than negative numbers is ignored by 3674 # the (incorrect) pattern, so this test does nothing. 3675 $end = $num ? ( $#hist - $num ) : 0; 3676 3677 # Set to the minimum if less than zero. 3678 $hist = 0 if $hist < 0; 3679 3680 # Start at the end of the array. 3681 # Stay in while we're still above the ending value. 3682 # Tick back by one each time around the loop. 3683 my $i; 3684 3685 for ( $i = $#hist ; $i > $end ; $i-- ) { 3686 3687 # Print the command unless it has no arguments. 3688 print $OUT "$i: ", $hist[$i], "\n" 3689 unless $hist[$i] =~ /^.?$/; 3690 } 3691 3692 next CMD; 3693 } 3694 3695 return; 3696} 3697 3698sub _handle_doc_command { 3699 my $self = shift; 3700 3701 # man, perldoc, doc - show manual pages. 3702 if (my ($man_page) 3703 = $DB::cmd =~ /\A(?:man|(?:perl)?doc)\b(?:\s+([^(]*))?\z/) { 3704 DB::runman($man_page); 3705 next CMD; 3706 } 3707 3708 return; 3709} 3710 3711sub _handle_p_command { 3712 my $self = shift; 3713 3714 my $print_cmd = 'print {$DB::OUT} '; 3715 # p - print (no args): print $_. 3716 if ($self->_is_full('p')) { 3717 $DB::cmd = $print_cmd . '$_'; 3718 } 3719 else { 3720 # p - print the given expression. 3721 $DB::cmd =~ s/\Ap\b/$print_cmd /; 3722 } 3723 3724 return; 3725} 3726 3727sub _handle_equal_sign_command { 3728 my $self = shift; 3729 3730 if ($DB::cmd =~ s/\A=\s*//) { 3731 my @keys; 3732 if ( length $DB::cmd == 0 ) { 3733 3734 # No args, get current aliases. 3735 @keys = sort keys %alias; 3736 } 3737 elsif ( my ( $k, $v ) = ( $DB::cmd =~ /^(\S+)\s+(\S.*)/ ) ) { 3738 3739 # Creating a new alias. $k is alias name, $v is 3740 # alias value. 3741 3742 # can't use $_ or kill //g state 3743 for my $x ( $k, $v ) { 3744 3745 # Escape "alarm" characters. 3746 $x =~ s/\a/\\a/g; 3747 } 3748 3749 # Substitute key for value, using alarm chars 3750 # as separators (which is why we escaped them in 3751 # the command). 3752 $alias{$k} = "s\a$k\a$v\a"; 3753 3754 # Turn off standard warn and die behavior. 3755 local $SIG{__DIE__}; 3756 local $SIG{__WARN__}; 3757 3758 # Is it valid Perl? 3759 unless ( eval "sub { s\a$k\a$v\a }; 1" ) { 3760 3761 # Nope. Bad alias. Say so and get out. 3762 print $OUT "Can't alias $k to $v: $@\n"; 3763 delete $alias{$k}; 3764 next CMD; 3765 } 3766 3767 # We'll only list the new one. 3768 @keys = ($k); 3769 } ## end elsif (my ($k, $v) = ($DB::cmd... 3770 3771 # The argument is the alias to list. 3772 else { 3773 @keys = ($DB::cmd); 3774 } 3775 3776 # List aliases. 3777 for my $k (@keys) { 3778 3779 # Messy metaquoting: Trim the substitution code off. 3780 # We use control-G as the delimiter because it's not 3781 # likely to appear in the alias. 3782 if ( ( my $v = $alias{$k} ) =~ ss\a$k\a(.*)\a$1 ) { 3783 3784 # Print the alias. 3785 print $OUT "$k\t= $1\n"; 3786 } 3787 elsif ( defined $alias{$k} ) { 3788 3789 # Couldn't trim it off; just print the alias code. 3790 print $OUT "$k\t$alias{$k}\n"; 3791 } 3792 else { 3793 3794 # No such, dude. 3795 print "No alias for $k\n"; 3796 } 3797 } ## end for my $k (@keys) 3798 next CMD; 3799 } 3800 3801 return; 3802} 3803 3804sub _handle_source_command { 3805 my $self = shift; 3806 3807 # source - read commands from a file (or pipe!) and execute. 3808 if (my $sourced_fn = $self->cmd_args) { 3809 if ( open my $fh, $sourced_fn ) { 3810 3811 # Opened OK; stick it in the list of file handles. 3812 push @cmdfhs, $fh; 3813 } 3814 else { 3815 3816 # Couldn't open it. 3817 DB::_db_warn("Can't execute '$sourced_fn': $!\n"); 3818 } 3819 next CMD; 3820 } 3821 3822 return; 3823} 3824 3825sub _handle_enable_disable_commands { 3826 my $self = shift; 3827 3828 my $which_cmd = $self->cmd_verb; 3829 my $position = $self->cmd_args; 3830 3831 if ($position !~ /\s/) { 3832 my ($fn, $line_num); 3833 if ($position =~ m{\A\d+\z}) 3834 { 3835 $fn = $DB::filename; 3836 $line_num = $position; 3837 } 3838 elsif (my ($new_fn, $new_line_num) 3839 = $position =~ m{\A(.*):(\d+)\z}) { 3840 ($fn, $line_num) = ($new_fn, $new_line_num); 3841 } 3842 else 3843 { 3844 DB::_db_warn("Wrong spec for enable/disable argument.\n"); 3845 } 3846 3847 if (defined($fn)) { 3848 if (DB::_has_breakpoint_data_ref($fn, $line_num)) { 3849 DB::_set_breakpoint_enabled_status($fn, $line_num, 3850 ($which_cmd eq 'enable' ? 1 : '') 3851 ); 3852 } 3853 else { 3854 DB::_db_warn("No breakpoint set at ${fn}:${line_num}\n"); 3855 } 3856 } 3857 3858 next CMD; 3859 } 3860 3861 return; 3862} 3863 3864sub _handle_save_command { 3865 my $self = shift; 3866 3867 if (my $new_fn = $self->cmd_args) { 3868 my $filename = $new_fn || '.perl5dbrc'; # default? 3869 if ( open my $fh, '>', $filename ) { 3870 3871 # chomp to remove extraneous newlines from source'd files 3872 chomp( my @truelist = 3873 map { m/\A\s*(save|source)/ ? "#$_" : $_ } 3874 @truehist ); 3875 print {$fh} join( "\n", @truelist ); 3876 print "commands saved in $filename\n"; 3877 } 3878 else { 3879 DB::_db_warn("Can't save debugger commands in '$new_fn': $!\n"); 3880 } 3881 next CMD; 3882 } 3883 3884 return; 3885} 3886 3887sub _n_or_s_and_arg_commands_generic { 3888 my ($self, $letter, $new_val) = @_; 3889 3890 # s - single-step. Remember the last command was 's'. 3891 if ($DB::cmd =~ s#\A\Q$letter\E\s#\$DB::single = $new_val;\n#) { 3892 $laststep = $letter; 3893 } 3894 3895 return; 3896} 3897 3898sub _handle_sh_command { 3899 my $self = shift; 3900 3901 # $sh$sh - run a shell command (if it's all ASCII). 3902 # Can't run shell commands with Unicode in the debugger, hmm. 3903 my $my_cmd = $DB::cmd; 3904 if ($my_cmd =~ m#\A$sh#gms) { 3905 3906 if ($my_cmd =~ m#\G\z#cgms) { 3907 # Run the user's shell. If none defined, run Bourne. 3908 # We resume execution when the shell terminates. 3909 DB::_db_system( $ENV{SHELL} || "/bin/sh" ); 3910 next CMD; 3911 } 3912 elsif ($my_cmd =~ m#\G$sh\s*(.*)#cgms) { 3913 # System it. 3914 DB::_db_system($1); 3915 next CMD; 3916 } 3917 elsif ($my_cmd =~ m#\G\s*(.*)#cgms) { 3918 DB::_db_system( $ENV{SHELL} || "/bin/sh", "-c", $1 ); 3919 next CMD; 3920 } 3921 } 3922} 3923 3924sub _handle_x_command { 3925 my $self = shift; 3926 3927 if ($DB::cmd =~ s#\Ax\b# #) { # Remainder gets done by DB::eval() 3928 $onetimeDump = 'dump'; # main::dumpvar shows the output 3929 3930 # handle special "x 3 blah" syntax XXX propagate 3931 # doc back to special variables. 3932 if ( $DB::cmd =~ s#\A\s*(\d+)(?=\s)# #) { 3933 $onetimedumpDepth = $1; 3934 } 3935 } 3936 3937 return; 3938} 3939 3940sub _handle_q_command { 3941 my $self = shift; 3942 3943 if ($self->_is_full('q')) { 3944 $fall_off_end = 1; 3945 DB::clean_ENV(); 3946 exit $?; 3947 } 3948 3949 return; 3950} 3951 3952sub _handle_cmd_wrapper_commands { 3953 my $self = shift; 3954 3955 DB::cmd_wrapper( $self->cmd_verb, $self->cmd_args, $line ); 3956 next CMD; 3957} 3958 3959sub _handle_special_char_cmd_wrapper_commands { 3960 my $self = shift; 3961 3962 # All of these commands were remapped in perl 5.8.0; 3963 # we send them off to the secondary dispatcher (see below). 3964 if (my ($cmd_letter, $my_arg) = $DB::cmd =~ /\A([<>\{]{1,2})\s*(.*)/so) { 3965 DB::cmd_wrapper( $cmd_letter, $my_arg, $line ); 3966 next CMD; 3967 } 3968 3969 return; 3970} 3971 3972} ## end DB::Obj 3973 3974package DB; 3975 3976# The following code may be executed now: 3977# BEGIN {warn 4} 3978 3979=head2 sub 3980 3981C<sub> is called whenever a subroutine call happens in the program being 3982debugged. The variable C<$DB::sub> contains the name of the subroutine 3983being called. 3984 3985The core function of this subroutine is to actually call the sub in the proper 3986context, capturing its output. This of course causes C<DB::DB> to get called 3987again, repeating until the subroutine ends and returns control to C<DB::sub> 3988again. Once control returns, C<DB::sub> figures out whether or not to dump the 3989return value, and returns its captured copy of the return value as its own 3990return value. The value then feeds back into the program being debugged as if 3991C<DB::sub> hadn't been there at all. 3992 3993C<sub> does all the work of printing the subroutine entry and exit messages 3994enabled by setting C<$frame>. It notes what sub the autoloader got called for, 3995and also prints the return value if needed (for the C<r> command and if 3996the 16 bit is set in C<$frame>). 3997 3998It also tracks the subroutine call depth by saving the current setting of 3999C<$single> in the C<@stack> package global; if this exceeds the value in 4000C<$deep>, C<sub> automatically turns on printing of the current depth by 4001setting the C<4> bit in C<$single>. In any case, it keeps the current setting 4002of stop/don't stop on entry to subs set as it currently is set. 4003 4004=head3 C<caller()> support 4005 4006If C<caller()> is called from the package C<DB>, it provides some 4007additional data, in the following order: 4008 4009=over 4 4010 4011=item * C<$package> 4012 4013The package name the sub was in 4014 4015=item * C<$filename> 4016 4017The filename it was defined in 4018 4019=item * C<$line> 4020 4021The line number it was defined on 4022 4023=item * C<$subroutine> 4024 4025The subroutine name; C<(eval)> if an C<eval>(). 4026 4027=item * C<$hasargs> 4028 40291 if it has arguments, 0 if not 4030 4031=item * C<$wantarray> 4032 40331 if array context, 0 if scalar context 4034 4035=item * C<$evaltext> 4036 4037The C<eval>() text, if any (undefined for C<eval BLOCK>) 4038 4039=item * C<$is_require> 4040 4041frame was created by a C<use> or C<require> statement 4042 4043=item * C<$hints> 4044 4045pragma information; subject to change between versions 4046 4047=item * C<$bitmask> 4048 4049pragma information; subject to change between versions 4050 4051=item * C<@DB::args> 4052 4053arguments with which the subroutine was invoked 4054 4055=back 4056 4057=cut 4058 4059use vars qw($deep); 4060 4061# We need to fully qualify the name ("DB::sub") to make "use strict;" 4062# happy. -- Shlomi Fish 4063 4064sub _indent_print_line_info { 4065 my ($offset, $str) = @_; 4066 4067 print_lineinfo( ' ' x ($stack_depth - $offset), $str); 4068 4069 return; 4070} 4071 4072sub _print_frame_message { 4073 my ($al) = @_; 4074 4075 if ($frame) { 4076 if ($frame & 4) { # Extended frame entry message 4077 _indent_print_line_info(-1, "in "); 4078 4079 # Why -1? But it works! :-( 4080 # Because print_trace will call add 1 to it and then call 4081 # dump_trace; this results in our skipping -1+1 = 0 stack frames 4082 # in dump_trace. 4083 # 4084 # Now it's 0 because we extracted a function. 4085 print_trace( $LINEINFO, 0, 1, 1, "$sub$al" ); 4086 } 4087 else { 4088 _indent_print_line_info(-1, "entering $sub$al\n" ); 4089 } 4090 } 4091 4092 return; 4093} 4094 4095sub DB::sub { 4096 # Do not use a regex in this subroutine -> results in corrupted memory 4097 # See: [perl #66110] 4098 4099 # lock ourselves under threads 4100 lock($DBGR); 4101 4102 # Whether or not the autoloader was running, a scalar to put the 4103 # sub's return value in (if needed), and an array to put the sub's 4104 # return value in (if needed). 4105 my ( $al, $ret, @ret ) = ""; 4106 if ($sub eq 'threads::new' && $ENV{PERL5DB_THREADED}) { 4107 print "creating new thread\n"; 4108 } 4109 4110 # If the last ten characters are '::AUTOLOAD', note we've traced 4111 # into AUTOLOAD for $sub. 4112 if ( length($sub) > 10 && substr( $sub, -10, 10 ) eq '::AUTOLOAD' ) { 4113 no strict 'refs'; 4114 $al = " for $$sub" if defined $$sub; 4115 } 4116 4117 # We stack the stack pointer and then increment it to protect us 4118 # from a situation that might unwind a whole bunch of call frames 4119 # at once. Localizing the stack pointer means that it will automatically 4120 # unwind the same amount when multiple stack frames are unwound. 4121 local $stack_depth = $stack_depth + 1; # Protect from non-local exits 4122 4123 # Expand @stack. 4124 $#stack = $stack_depth; 4125 4126 # Save current single-step setting. 4127 $stack[-1] = $single; 4128 4129 # Turn off all flags except single-stepping. 4130 $single &= 1; 4131 4132 # If we've gotten really deeply recursed, turn on the flag that will 4133 # make us stop with the 'deep recursion' message. 4134 $single |= 4 if $stack_depth == $deep; 4135 4136 # If frame messages are on ... 4137 4138 _print_frame_message($al); 4139 # standard frame entry message 4140 4141 my $print_exit_msg = sub { 4142 # Check for exit trace messages... 4143 if ($frame & 2) 4144 { 4145 if ($frame & 4) # Extended exit message 4146 { 4147 _indent_print_line_info(0, "out "); 4148 print_trace( $LINEINFO, 0, 1, 1, "$sub$al" ); 4149 } 4150 else 4151 { 4152 _indent_print_line_info(0, "exited $sub$al\n" ); 4153 } 4154 } 4155 return; 4156 }; 4157 4158 # Determine the sub's return type, and capture appropriately. 4159 if (wantarray) { 4160 4161 # Called in array context. call sub and capture output. 4162 # DB::DB will recursively get control again if appropriate; we'll come 4163 # back here when the sub is finished. 4164 { 4165 no strict 'refs'; 4166 @ret = &$sub; 4167 } 4168 4169 # Pop the single-step value back off the stack. 4170 $single |= $stack[ $stack_depth-- ]; 4171 4172 $print_exit_msg->(); 4173 4174 # Print the return info if we need to. 4175 if ( $doret eq $stack_depth or $frame & 16 ) { 4176 4177 # Turn off output record separator. 4178 local $\ = ''; 4179 my $fh = ( $doret eq $stack_depth ? $OUT : $LINEINFO ); 4180 4181 # Indent if we're printing because of $frame tracing. 4182 if ($frame & 16) 4183 { 4184 print {$fh} ' ' x $stack_depth; 4185 } 4186 4187 # Print the return value. 4188 print {$fh} "list context return from $sub:\n"; 4189 dumpit( $fh, \@ret ); 4190 4191 # And don't print it again. 4192 $doret = -2; 4193 } ## end if ($doret eq $stack_depth... 4194 # And we have to return the return value now. 4195 @ret; 4196 } ## end if (wantarray) 4197 4198 # Scalar context. 4199 else { 4200 if ( defined wantarray ) { 4201 no strict 'refs'; 4202 # Save the value if it's wanted at all. 4203 $ret = &$sub; 4204 } 4205 else { 4206 no strict 'refs'; 4207 # Void return, explicitly. 4208 &$sub; 4209 undef $ret; 4210 } 4211 4212 # Pop the single-step value off the stack. 4213 $single |= $stack[ $stack_depth-- ]; 4214 4215 # If we're doing exit messages... 4216 $print_exit_msg->(); 4217 4218 # If we are supposed to show the return value... same as before. 4219 if ( $doret eq $stack_depth or $frame & 16 and defined wantarray ) { 4220 local $\ = ''; 4221 my $fh = ( $doret eq $stack_depth ? $OUT : $LINEINFO ); 4222 print $fh ( ' ' x $stack_depth ) if $frame & 16; 4223 print $fh ( 4224 defined wantarray 4225 ? "scalar context return from $sub: " 4226 : "void context return from $sub\n" 4227 ); 4228 dumpit( $fh, $ret ) if defined wantarray; 4229 $doret = -2; 4230 } ## end if ($doret eq $stack_depth... 4231 4232 # Return the appropriate scalar value. 4233 $ret; 4234 } ## end else [ if (wantarray) 4235} ## end sub _sub 4236 4237sub lsub : lvalue { 4238 4239 no strict 'refs'; 4240 4241 # lock ourselves under threads 4242 lock($DBGR); 4243 4244 # Whether or not the autoloader was running, a scalar to put the 4245 # sub's return value in (if needed), and an array to put the sub's 4246 # return value in (if needed). 4247 my ( $al, $ret, @ret ) = ""; 4248 if ($sub =~ /^threads::new$/ && $ENV{PERL5DB_THREADED}) { 4249 print "creating new thread\n"; 4250 } 4251 4252 # If the last ten characters are C'::AUTOLOAD', note we've traced 4253 # into AUTOLOAD for $sub. 4254 if ( length($sub) > 10 && substr( $sub, -10, 10 ) eq '::AUTOLOAD' ) { 4255 $al = " for $$sub"; 4256 } 4257 4258 # We stack the stack pointer and then increment it to protect us 4259 # from a situation that might unwind a whole bunch of call frames 4260 # at once. Localizing the stack pointer means that it will automatically 4261 # unwind the same amount when multiple stack frames are unwound. 4262 local $stack_depth = $stack_depth + 1; # Protect from non-local exits 4263 4264 # Expand @stack. 4265 $#stack = $stack_depth; 4266 4267 # Save current single-step setting. 4268 $stack[-1] = $single; 4269 4270 # Turn off all flags except single-stepping. 4271 $single &= 1; 4272 4273 # If we've gotten really deeply recursed, turn on the flag that will 4274 # make us stop with the 'deep recursion' message. 4275 $single |= 4 if $stack_depth == $deep; 4276 4277 # If frame messages are on ... 4278 _print_frame_message($al); 4279 4280 # Pop the single-step value back off the stack. 4281 $single |= $stack[ $stack_depth-- ]; 4282 4283 # call the original lvalue sub. 4284 &$sub; 4285} 4286 4287# Abstracting common code from multiple places elsewhere: 4288sub depth_print_lineinfo { 4289 my $always_print = shift; 4290 4291 print_lineinfo( @_ ) if ($always_print or $stack_depth < $trace_to_depth); 4292} 4293 4294=head1 EXTENDED COMMAND HANDLING AND THE COMMAND API 4295 4296In Perl 5.8.0, there was a major realignment of the commands and what they did, 4297Most of the changes were to systematize the command structure and to eliminate 4298commands that threw away user input without checking. 4299 4300The following sections describe the code added to make it easy to support 4301multiple command sets with conflicting command names. This section is a start 4302at unifying all command processing to make it simpler to develop commands. 4303 4304Note that all the cmd_[a-zA-Z] subroutines require the command name, a line 4305number, and C<$dbline> (the current line) as arguments. 4306 4307Support functions in this section which have multiple modes of failure C<die> 4308on error; the rest simply return a false value. 4309 4310The user-interface functions (all of the C<cmd_*> functions) just output 4311error messages. 4312 4313=head2 C<%set> 4314 4315The C<%set> hash defines the mapping from command letter to subroutine 4316name suffix. 4317 4318C<%set> is a two-level hash, indexed by set name and then by command name. 4319Note that trying to set the CommandSet to C<foobar> simply results in the 43205.8.0 command set being used, since there's no top-level entry for C<foobar>. 4321 4322=cut 4323 4324### The API section 4325 4326my %set = ( # 4327 'pre580' => { 4328 'a' => 'pre580_a', 4329 'A' => 'pre580_null', 4330 'b' => 'pre580_b', 4331 'B' => 'pre580_null', 4332 'd' => 'pre580_null', 4333 'D' => 'pre580_D', 4334 'h' => 'pre580_h', 4335 'M' => 'pre580_null', 4336 'O' => 'o', 4337 'o' => 'pre580_null', 4338 'v' => 'M', 4339 'w' => 'v', 4340 'W' => 'pre580_W', 4341 }, 4342 'pre590' => { 4343 '<' => 'pre590_prepost', 4344 '<<' => 'pre590_prepost', 4345 '>' => 'pre590_prepost', 4346 '>>' => 'pre590_prepost', 4347 '{' => 'pre590_prepost', 4348 '{{' => 'pre590_prepost', 4349 }, 4350); 4351 4352my %breakpoints_data; 4353 4354sub _has_breakpoint_data_ref { 4355 my ($filename, $line) = @_; 4356 4357 return ( 4358 exists( $breakpoints_data{$filename} ) 4359 and 4360 exists( $breakpoints_data{$filename}{$line} ) 4361 ); 4362} 4363 4364sub _get_breakpoint_data_ref { 4365 my ($filename, $line) = @_; 4366 4367 return ($breakpoints_data{$filename}{$line} ||= +{}); 4368} 4369 4370sub _delete_breakpoint_data_ref { 4371 my ($filename, $line) = @_; 4372 4373 delete($breakpoints_data{$filename}{$line}); 4374 if (! scalar(keys( %{$breakpoints_data{$filename}} )) ) { 4375 delete($breakpoints_data{$filename}); 4376 } 4377 4378 return; 4379} 4380 4381sub _set_breakpoint_enabled_status { 4382 my ($filename, $line, $status) = @_; 4383 4384 _get_breakpoint_data_ref($filename, $line)->{'enabled'} = 4385 ($status ? 1 : '') 4386 ; 4387 4388 return; 4389} 4390 4391sub _enable_breakpoint_temp_enabled_status { 4392 my ($filename, $line) = @_; 4393 4394 _get_breakpoint_data_ref($filename, $line)->{'temp_enabled'} = 1; 4395 4396 return; 4397} 4398 4399sub _cancel_breakpoint_temp_enabled_status { 4400 my ($filename, $line) = @_; 4401 4402 my $ref = _get_breakpoint_data_ref($filename, $line); 4403 4404 delete ($ref->{'temp_enabled'}); 4405 4406 if (! %$ref) { 4407 _delete_breakpoint_data_ref($filename, $line); 4408 } 4409 4410 return; 4411} 4412 4413sub _is_breakpoint_enabled { 4414 my ($filename, $line) = @_; 4415 4416 my $data_ref = _get_breakpoint_data_ref($filename, $line); 4417 return ($data_ref->{'enabled'} || $data_ref->{'temp_enabled'}); 4418} 4419 4420=head2 C<cmd_wrapper()> (API) 4421 4422C<cmd_wrapper()> allows the debugger to switch command sets 4423depending on the value of the C<CommandSet> option. 4424 4425It tries to look up the command in the C<%set> package-level I<lexical> 4426(which means external entities can't fiddle with it) and create the name of 4427the sub to call based on the value found in the hash (if it's there). I<All> 4428of the commands to be handled in a set have to be added to C<%set>; if they 4429aren't found, the 5.8.0 equivalent is called (if there is one). 4430 4431This code uses symbolic references. 4432 4433=cut 4434 4435sub cmd_wrapper { 4436 my $cmd = shift; 4437 my $line = shift; 4438 my $dblineno = shift; 4439 4440 # Assemble the command subroutine's name by looking up the 4441 # command set and command name in %set. If we can't find it, 4442 # default to the older version of the command. 4443 my $call = 'cmd_' 4444 . ( $set{$CommandSet}{$cmd} 4445 || ( $cmd =~ /\A[<>{]+/o ? 'prepost' : $cmd ) ); 4446 4447 # Call the command subroutine, call it by name. 4448 return __PACKAGE__->can($call)->( $cmd, $line, $dblineno ); 4449} ## end sub cmd_wrapper 4450 4451=head3 C<cmd_a> (command) 4452 4453The C<a> command handles pre-execution actions. These are associated with a 4454particular line, so they're stored in C<%dbline>. We default to the current 4455line if none is specified. 4456 4457=cut 4458 4459sub cmd_a { 4460 my $cmd = shift; 4461 my $line = shift || ''; # [.|line] expr 4462 my $dbline = shift; 4463 4464 # If it's dot (here), or not all digits, use the current line. 4465 $line =~ s/\A\./$dbline/; 4466 4467 # Should be a line number followed by an expression. 4468 if ( my ($lineno, $expr) = $line =~ /^\s*(\d*)\s*(\S.+)/ ) { 4469 4470 if (! length($lineno)) { 4471 $lineno = $dbline; 4472 } 4473 4474 # If we have an expression ... 4475 if ( length $expr ) { 4476 4477 # ... but the line isn't breakable, complain. 4478 if ( $dbline[$lineno] == 0 ) { 4479 print $OUT 4480 "Line $lineno($dbline[$lineno]) does not have an action?\n"; 4481 } 4482 else { 4483 4484 # It's executable. Record that the line has an action. 4485 $had_breakpoints{$filename} |= 2; 4486 4487 # Remove any action, temp breakpoint, etc. 4488 $dbline{$lineno} =~ s/\0[^\0]*//; 4489 4490 # Add the action to the line. 4491 $dbline{$lineno} .= "\0" . action($expr); 4492 4493 _set_breakpoint_enabled_status($filename, $lineno, 1); 4494 } 4495 } ## end if (length $expr) 4496 } ## end if ($line =~ /^\s*(\d*)\s*(\S.+)/) 4497 else { 4498 4499 # Syntax wrong. 4500 print $OUT 4501 "Adding an action requires an optional lineno and an expression\n" 4502 ; # hint 4503 } 4504} ## end sub cmd_a 4505 4506=head3 C<cmd_A> (command) 4507 4508Delete actions. Similar to above, except the delete code is in a separate 4509subroutine, C<delete_action>. 4510 4511=cut 4512 4513sub cmd_A { 4514 my $cmd = shift; 4515 my $line = shift || ''; 4516 my $dbline = shift; 4517 4518 # Dot is this line. 4519 $line =~ s/^\./$dbline/; 4520 4521 # Call delete_action with a null param to delete them all. 4522 # The '1' forces the eval to be true. It'll be false only 4523 # if delete_action blows up for some reason, in which case 4524 # we print $@ and get out. 4525 if ( $line eq '*' ) { 4526 if (! eval { _delete_all_actions(); 1 }) { 4527 print {$OUT} $@; 4528 return; 4529 } 4530 } 4531 4532 # There's a real line number. Pass it to delete_action. 4533 # Error trapping is as above. 4534 elsif ( $line =~ /^(\S.*)/ ) { 4535 if (! eval { delete_action($1); 1 }) { 4536 print {$OUT} $@; 4537 return; 4538 } 4539 } 4540 4541 # Swing and a miss. Bad syntax. 4542 else { 4543 print $OUT 4544 "Deleting an action requires a line number, or '*' for all\n" ; # hint 4545 } 4546} ## end sub cmd_A 4547 4548=head3 C<delete_action> (API) 4549 4550C<delete_action> accepts either a line number or C<undef>. If a line number 4551is specified, we check for the line being executable (if it's not, it 4552couldn't have had an action). If it is, we just take the action off (this 4553will get any kind of an action, including breakpoints). 4554 4555=cut 4556 4557sub _remove_action_from_dbline { 4558 my $i = shift; 4559 4560 $dbline{$i} =~ s/\0[^\0]*//; # \^a 4561 delete $dbline{$i} if $dbline{$i} eq ''; 4562 4563 return; 4564} 4565 4566sub _delete_all_actions { 4567 print {$OUT} "Deleting all actions...\n"; 4568 4569 for my $file ( keys %had_breakpoints ) { 4570 local *dbline = $main::{ '_<' . $file }; 4571 $max = $#dbline; 4572 my $was; 4573 for my $i (1 .. $max) { 4574 if ( defined $dbline{$i} ) { 4575 _remove_action_from_dbline($i); 4576 } 4577 } 4578 4579 unless ( $had_breakpoints{$file} &= ~2 ) { 4580 delete $had_breakpoints{$file}; 4581 } 4582 } 4583 4584 return; 4585} 4586 4587sub delete_action { 4588 my $i = shift; 4589 4590 if ( defined($i) ) { 4591 # Can there be one? 4592 die "Line $i has no action .\n" if $dbline[$i] == 0; 4593 4594 # Nuke whatever's there. 4595 _remove_action_from_dbline($i); 4596 } 4597 else { 4598 _delete_all_actions(); 4599 } 4600} 4601 4602=head3 C<cmd_b> (command) 4603 4604Set breakpoints. Since breakpoints can be set in so many places, in so many 4605ways, conditionally or not, the breakpoint code is kind of complex. Mostly, 4606we try to parse the command type, and then shuttle it off to an appropriate 4607subroutine to actually do the work of setting the breakpoint in the right 4608place. 4609 4610=cut 4611 4612sub cmd_b { 4613 my $cmd = shift; 4614 my $line = shift; # [.|line] [cond] 4615 my $dbline = shift; 4616 4617 my $default_cond = sub { 4618 my $cond = shift; 4619 return length($cond) ? $cond : '1'; 4620 }; 4621 4622 # Make . the current line number if it's there.. 4623 $line =~ s/^\.(\s|\z)/$dbline$1/; 4624 4625 # No line number, no condition. Simple break on current line. 4626 if ( $line =~ /^\s*$/ ) { 4627 cmd_b_line( $dbline, 1 ); 4628 } 4629 4630 # Break on load for a file. 4631 elsif ( my ($file) = $line =~ /^load\b\s*(.*)/ ) { 4632 $file =~ s/\s+\z//; 4633 cmd_b_load($file); 4634 } 4635 4636 # b compile|postpone <some sub> [<condition>] 4637 # The interpreter actually traps this one for us; we just put the 4638 # necessary condition in the %postponed hash. 4639 elsif ( my ($action, $subname, $cond) 4640 = $line =~ /^(postpone|compile)\b\s*([':A-Za-z_][':\w]*)\s*(.*)/ ) { 4641 4642 # De-Perl4-ify the name - ' separators to ::. 4643 $subname =~ s/'/::/g; 4644 4645 # Qualify it into the current package unless it's already qualified. 4646 $subname = "${package}::" . $subname unless $subname =~ /::/; 4647 4648 # Add main if it starts with ::. 4649 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::"; 4650 4651 # Save the break type for this sub. 4652 $postponed{$subname} = (($action eq 'postpone') 4653 ? ( "break +0 if " . $default_cond->($cond) ) 4654 : "compile"); 4655 } ## end elsif ($line =~ ... 4656 # b <filename>:<line> [<condition>] 4657 elsif (my ($filename, $line_num, $cond) 4658 = $line =~ /\A(\S+[^:]):(\d+)\s*(.*)/ms) { 4659 cmd_b_filename_line( 4660 $filename, 4661 $line_num, 4662 (length($cond) ? $cond : '1'), 4663 ); 4664 } 4665 # b <sub name> [<condition>] 4666 elsif ( my ($new_subname, $new_cond) = 4667 $line =~ /^([':A-Za-z_][':\w]*(?:\[.*\])?)\s*(.*)/ ) { 4668 4669 # 4670 $subname = $new_subname; 4671 cmd_b_sub( $subname, $default_cond->($new_cond) ); 4672 } 4673 4674 # b <line> [<condition>]. 4675 elsif ( my ($line_n, $cond) = $line =~ /^(\d*)\s*(.*)/ ) { 4676 4677 # Capture the line. If none, it's the current line. 4678 $line = $line_n || $dbline; 4679 4680 # Break on line. 4681 cmd_b_line( $line, $default_cond->($cond) ); 4682 } 4683 4684 # Line didn't make sense. 4685 else { 4686 print "confused by line($line)?\n"; 4687 } 4688 4689 return; 4690} ## end sub cmd_b 4691 4692=head3 C<break_on_load> (API) 4693 4694We want to break when this file is loaded. Mark this file in the 4695C<%break_on_load> hash, and note that it has a breakpoint in 4696C<%had_breakpoints>. 4697 4698=cut 4699 4700sub break_on_load { 4701 my $file = shift; 4702 $break_on_load{$file} = 1; 4703 $had_breakpoints{$file} |= 1; 4704} 4705 4706=head3 C<report_break_on_load> (API) 4707 4708Gives us an array of filenames that are set to break on load. Note that 4709only files with break-on-load are in here, so simply showing the keys 4710suffices. 4711 4712=cut 4713 4714sub report_break_on_load { 4715 sort keys %break_on_load; 4716} 4717 4718=head3 C<cmd_b_load> (command) 4719 4720We take the file passed in and try to find it in C<%INC> (which maps modules 4721to files they came from). We mark those files for break-on-load via 4722C<break_on_load> and then report that it was done. 4723 4724=cut 4725 4726sub cmd_b_load { 4727 my $file = shift; 4728 my @files; 4729 4730 # This is a block because that way we can use a redo inside it 4731 # even without there being any looping structure at all outside it. 4732 { 4733 4734 # Save short name and full path if found. 4735 push @files, $file; 4736 push @files, $::INC{$file} if $::INC{$file}; 4737 4738 # Tack on .pm and do it again unless there was a '.' in the name 4739 # already. 4740 $file .= '.pm', redo unless $file =~ /\./; 4741 } 4742 4743 # Do the real work here. 4744 break_on_load($_) for @files; 4745 4746 # All the files that have break-on-load breakpoints. 4747 @files = report_break_on_load; 4748 4749 # Normalize for the purposes of our printing this. 4750 local $\ = ''; 4751 local $" = ' '; 4752 print $OUT "Will stop on load of '@files'.\n"; 4753} ## end sub cmd_b_load 4754 4755=head3 C<$filename_error> (API package global) 4756 4757Several of the functions we need to implement in the API need to work both 4758on the current file and on other files. We don't want to duplicate code, so 4759C<$filename_error> is used to contain the name of the file that's being 4760worked on (if it's not the current one). 4761 4762We can now build functions in pairs: the basic function works on the current 4763file, and uses C<$filename_error> as part of its error message. Since this is 4764initialized to C<"">, no filename will appear when we are working on the 4765current file. 4766 4767The second function is a wrapper which does the following: 4768 4769=over 4 4770 4771=item * 4772 4773Localizes C<$filename_error> and sets it to the name of the file to be processed. 4774 4775=item * 4776 4777Localizes the C<*dbline> glob and reassigns it to point to the file we want to process. 4778 4779=item * 4780 4781Calls the first function. 4782 4783The first function works on the I<current> file (i.e., the one we changed to), 4784and prints C<$filename_error> in the error message (the name of the other file) 4785if it needs to. When the functions return, C<*dbline> is restored to point 4786to the actual current file (the one we're executing in) and 4787C<$filename_error> is restored to C<"">. This restores everything to 4788the way it was before the second function was called at all. 4789 4790See the comments in C<breakable_line> and C<breakable_line_in_file> for more 4791details. 4792 4793=back 4794 4795=cut 4796 4797use vars qw($filename_error); 4798$filename_error = ''; 4799 4800=head3 breakable_line(from, to) (API) 4801 4802The subroutine decides whether or not a line in the current file is breakable. 4803It walks through C<@dbline> within the range of lines specified, looking for 4804the first line that is breakable. 4805 4806If C<$to> is greater than C<$from>, the search moves forwards, finding the 4807first line I<after> C<$to> that's breakable, if there is one. 4808 4809If C<$from> is greater than C<$to>, the search goes I<backwards>, finding the 4810first line I<before> C<$to> that's breakable, if there is one. 4811 4812=cut 4813 4814sub breakable_line { 4815 4816 my ( $from, $to ) = @_; 4817 4818 # $i is the start point. (Where are the FORTRAN programs of yesteryear?) 4819 my $i = $from; 4820 4821 # If there are at least 2 arguments, we're trying to search a range. 4822 if ( @_ >= 2 ) { 4823 4824 # $delta is positive for a forward search, negative for a backward one. 4825 my $delta = $from < $to ? +1 : -1; 4826 4827 # Keep us from running off the ends of the file. 4828 my $limit = $delta > 0 ? $#dbline : 1; 4829 4830 # Clever test. If you're a mathematician, it's obvious why this 4831 # test works. If not: 4832 # If $delta is positive (going forward), $limit will be $#dbline. 4833 # If $to is less than $limit, ($limit - $to) will be positive, times 4834 # $delta of 1 (positive), so the result is > 0 and we should use $to 4835 # as the stopping point. 4836 # 4837 # If $to is greater than $limit, ($limit - $to) is negative, 4838 # times $delta of 1 (positive), so the result is < 0 and we should 4839 # use $limit ($#dbline) as the stopping point. 4840 # 4841 # If $delta is negative (going backward), $limit will be 1. 4842 # If $to is zero, ($limit - $to) will be 1, times $delta of -1 4843 # (negative) so the result is > 0, and we use $to as the stopping 4844 # point. 4845 # 4846 # If $to is less than zero, ($limit - $to) will be positive, 4847 # times $delta of -1 (negative), so the result is not > 0, and 4848 # we use $limit (1) as the stopping point. 4849 # 4850 # If $to is 1, ($limit - $to) will zero, times $delta of -1 4851 # (negative), still giving zero; the result is not > 0, and 4852 # we use $limit (1) as the stopping point. 4853 # 4854 # if $to is >1, ($limit - $to) will be negative, times $delta of -1 4855 # (negative), giving a positive (>0) value, so we'll set $limit to 4856 # $to. 4857 4858 $limit = $to if ( $limit - $to ) * $delta > 0; 4859 4860 # The real search loop. 4861 # $i starts at $from (the point we want to start searching from). 4862 # We move through @dbline in the appropriate direction (determined 4863 # by $delta: either -1 (back) or +1 (ahead). 4864 # We stay in as long as we haven't hit an executable line 4865 # ($dbline[$i] == 0 means not executable) and we haven't reached 4866 # the limit yet (test similar to the above). 4867 $i += $delta while $dbline[$i] == 0 and ( $limit - $i ) * $delta > 0; 4868 4869 } ## end if (@_ >= 2) 4870 4871 # If $i points to a line that is executable, return that. 4872 return $i unless $dbline[$i] == 0; 4873 4874 # Format the message and print it: no breakable lines in range. 4875 my ( $pl, $upto ) = ( '', '' ); 4876 ( $pl, $upto ) = ( 's', "..$to" ) if @_ >= 2 and $from != $to; 4877 4878 # If there's a filename in filename_error, we'll see it. 4879 # If not, not. 4880 die "Line$pl $from$upto$filename_error not breakable\n"; 4881} ## end sub breakable_line 4882 4883=head3 breakable_line_in_filename(file, from, to) (API) 4884 4885Like C<breakable_line>, but look in another file. 4886 4887=cut 4888 4889sub breakable_line_in_filename { 4890 4891 # Capture the file name. 4892 my ($f) = shift; 4893 4894 # Swap the magic line array over there temporarily. 4895 local *dbline = $main::{ '_<' . $f }; 4896 4897 # If there's an error, it's in this other file. 4898 local $filename_error = " of '$f'"; 4899 4900 # Find the breakable line. 4901 breakable_line(@_); 4902 4903 # *dbline and $filename_error get restored when this block ends. 4904 4905} ## end sub breakable_line_in_filename 4906 4907=head3 break_on_line(lineno, [condition]) (API) 4908 4909Adds a breakpoint with the specified condition (or 1 if no condition was 4910specified) to the specified line. Dies if it can't. 4911 4912=cut 4913 4914sub break_on_line { 4915 my $i = shift; 4916 my $cond = @_ ? shift(@_) : 1; 4917 4918 my $inii = $i; 4919 my $after = ''; 4920 my $pl = ''; 4921 4922 # Woops, not a breakable line. $filename_error allows us to say 4923 # if it was in a different file. 4924 die "Line $i$filename_error not breakable.\n" if $dbline[$i] == 0; 4925 4926 # Mark this file as having breakpoints in it. 4927 $had_breakpoints{$filename} |= 1; 4928 4929 # If there is an action or condition here already ... 4930 if ( $dbline{$i} ) { 4931 4932 # ... swap this condition for the existing one. 4933 $dbline{$i} =~ s/^[^\0]*/$cond/; 4934 } 4935 else { 4936 4937 # Nothing here - just add the condition. 4938 $dbline{$i} = $cond; 4939 4940 _set_breakpoint_enabled_status($filename, $i, 1); 4941 } 4942 4943 return; 4944} ## end sub break_on_line 4945 4946=head3 cmd_b_line(line, [condition]) (command) 4947 4948Wrapper for C<break_on_line>. Prints the failure message if it 4949doesn't work. 4950 4951=cut 4952 4953sub cmd_b_line { 4954 if (not eval { break_on_line(@_); 1 }) { 4955 local $\ = ''; 4956 print $OUT $@ and return; 4957 } 4958 4959 return; 4960} ## end sub cmd_b_line 4961 4962=head3 cmd_b_filename_line(line, [condition]) (command) 4963 4964Wrapper for C<break_on_filename_line>. Prints the failure message if it 4965doesn't work. 4966 4967=cut 4968 4969sub cmd_b_filename_line { 4970 if (not eval { break_on_filename_line(@_); 1 }) { 4971 local $\ = ''; 4972 print $OUT $@ and return; 4973 } 4974 4975 return; 4976} 4977 4978=head3 break_on_filename_line(file, line, [condition]) (API) 4979 4980Switches to the file specified and then calls C<break_on_line> to set 4981the breakpoint. 4982 4983=cut 4984 4985sub break_on_filename_line { 4986 my $f = shift; 4987 my $i = shift; 4988 my $cond = @_ ? shift(@_) : 1; 4989 4990 # Switch the magical hash temporarily. 4991 local *dbline = $main::{ '_<' . $f }; 4992 4993 # Localize the variables that break_on_line uses to make its message. 4994 local $filename_error = " of '$f'"; 4995 local $filename = $f; 4996 4997 # Add the breakpoint. 4998 break_on_line( $i, $cond ); 4999 5000 return; 5001} ## end sub break_on_filename_line 5002 5003=head3 break_on_filename_line_range(file, from, to, [condition]) (API) 5004 5005Switch to another file, search the range of lines specified for an 5006executable one, and put a breakpoint on the first one you find. 5007 5008=cut 5009 5010sub break_on_filename_line_range { 5011 my $f = shift; 5012 my $from = shift; 5013 my $to = shift; 5014 my $cond = @_ ? shift(@_) : 1; 5015 5016 # Find a breakable line if there is one. 5017 my $i = breakable_line_in_filename( $f, $from, $to ); 5018 5019 # Add the breakpoint. 5020 break_on_filename_line( $f, $i, $cond ); 5021 5022 return; 5023} ## end sub break_on_filename_line_range 5024 5025=head3 subroutine_filename_lines(subname, [condition]) (API) 5026 5027Search for a subroutine within a given file. The condition is ignored. 5028Uses C<find_sub> to locate the desired subroutine. 5029 5030=cut 5031 5032sub subroutine_filename_lines { 5033 my ( $subname ) = @_; 5034 5035 # Returned value from find_sub() is fullpathname:startline-endline. 5036 # The match creates the list (fullpathname, start, end). 5037 return (find_sub($subname) =~ /^(.*):(\d+)-(\d+)$/); 5038} ## end sub subroutine_filename_lines 5039 5040=head3 break_subroutine(subname) (API) 5041 5042Places a break on the first line possible in the specified subroutine. Uses 5043C<subroutine_filename_lines> to find the subroutine, and 5044C<break_on_filename_line_range> to place the break. 5045 5046=cut 5047 5048sub break_subroutine { 5049 my $subname = shift; 5050 5051 # Get filename, start, and end. 5052 my ( $file, $s, $e ) = subroutine_filename_lines($subname) 5053 or die "Subroutine $subname not found.\n"; 5054 5055 5056 # Null condition changes to '1' (always true). 5057 my $cond = @_ ? shift(@_) : 1; 5058 5059 # Put a break the first place possible in the range of lines 5060 # that make up this subroutine. 5061 break_on_filename_line_range( $file, $s, $e, $cond ); 5062 5063 return; 5064} ## end sub break_subroutine 5065 5066=head3 cmd_b_sub(subname, [condition]) (command) 5067 5068We take the incoming subroutine name and fully-qualify it as best we can. 5069 5070=over 4 5071 5072=item 1. If it's already fully-qualified, leave it alone. 5073 5074=item 2. Try putting it in the current package. 5075 5076=item 3. If it's not there, try putting it in CORE::GLOBAL if it exists there. 5077 5078=item 4. If it starts with '::', put it in 'main::'. 5079 5080=back 5081 5082After all this cleanup, we call C<break_subroutine> to try to set the 5083breakpoint. 5084 5085=cut 5086 5087sub cmd_b_sub { 5088 my $subname = shift; 5089 my $cond = @_ ? shift : 1; 5090 5091 # If the subname isn't a code reference, qualify it so that 5092 # break_subroutine() will work right. 5093 if ( ref($subname) ne 'CODE' ) { 5094 5095 # Not Perl 4. 5096 $subname =~ s/'/::/g; 5097 my $s = $subname; 5098 5099 # Put it in this package unless it's already qualified. 5100 if ($subname !~ /::/) 5101 { 5102 $subname = $package . '::' . $subname; 5103 }; 5104 5105 # Requalify it into CORE::GLOBAL if qualifying it into this 5106 # package resulted in its not being defined, but only do so 5107 # if it really is in CORE::GLOBAL. 5108 my $core_name = "CORE::GLOBAL::$s"; 5109 if ((!defined(&$subname)) 5110 and ($s !~ /::/) 5111 and (defined &{$core_name})) 5112 { 5113 $subname = $core_name; 5114 } 5115 5116 # Put it in package 'main' if it has a leading ::. 5117 if ($subname =~ /\A::/) 5118 { 5119 $subname = "main" . $subname; 5120 } 5121 } ## end if ( ref($subname) ne 'CODE' ) { 5122 5123 # Try to set the breakpoint. 5124 if (not eval { break_subroutine( $subname, $cond ); 1 }) { 5125 local $\ = ''; 5126 print {$OUT} $@; 5127 return; 5128 } 5129 5130 return; 5131} ## end sub cmd_b_sub 5132 5133=head3 C<cmd_B> - delete breakpoint(s) (command) 5134 5135The command mostly parses the command line and tries to turn the argument 5136into a line spec. If it can't, it uses the current line. It then calls 5137C<delete_breakpoint> to actually do the work. 5138 5139If C<*> is specified, C<cmd_B> calls C<delete_breakpoint> with no arguments, 5140thereby deleting all the breakpoints. 5141 5142=cut 5143 5144sub cmd_B { 5145 my $cmd = shift; 5146 5147 # No line spec? Use dbline. 5148 # If there is one, use it if it's non-zero, or wipe it out if it is. 5149 my $line = ( $_[0] =~ /\A\./ ) ? $dbline : (shift || ''); 5150 my $dbline = shift; 5151 5152 # If the line was dot, make the line the current one. 5153 $line =~ s/^\./$dbline/; 5154 5155 # If it's * we're deleting all the breakpoints. 5156 if ( $line eq '*' ) { 5157 if (not eval { delete_breakpoint(); 1 }) { 5158 print {$OUT} $@; 5159 } 5160 } 5161 5162 # If there is a line spec, delete the breakpoint on that line. 5163 elsif ( $line =~ /\A(\S.*)/ ) { 5164 if (not eval { delete_breakpoint( $line || $dbline ); 1 }) { 5165 local $\ = ''; 5166 print {$OUT} $@; 5167 } 5168 } ## end elsif ($line =~ /^(\S.*)/) 5169 5170 # No line spec. 5171 else { 5172 print {$OUT} 5173 "Deleting a breakpoint requires a line number, or '*' for all\n" 5174 ; # hint 5175 } 5176 5177 return; 5178} ## end sub cmd_B 5179 5180=head3 delete_breakpoint([line]) (API) 5181 5182This actually does the work of deleting either a single breakpoint, or all 5183of them. 5184 5185For a single line, we look for it in C<@dbline>. If it's nonbreakable, we 5186just drop out with a message saying so. If it is, we remove the condition 5187part of the 'condition\0action' that says there's a breakpoint here. If, 5188after we've done that, there's nothing left, we delete the corresponding 5189line in C<%dbline> to signal that no action needs to be taken for this line. 5190 5191For all breakpoints, we iterate through the keys of C<%had_breakpoints>, 5192which lists all currently-loaded files which have breakpoints. We then look 5193at each line in each of these files, temporarily switching the C<%dbline> 5194and C<@dbline> structures to point to the files in question, and do what 5195we did in the single line case: delete the condition in C<@dbline>, and 5196delete the key in C<%dbline> if nothing's left. 5197 5198We then wholesale delete C<%postponed>, C<%postponed_file>, and 5199C<%break_on_load>, because these structures contain breakpoints for files 5200and code that haven't been loaded yet. We can just kill these off because there 5201are no magical debugger structures associated with them. 5202 5203=cut 5204 5205sub _remove_breakpoint_entry { 5206 my ($fn, $i) = @_; 5207 5208 delete $dbline{$i}; 5209 _delete_breakpoint_data_ref($fn, $i); 5210 5211 return; 5212} 5213 5214sub _delete_all_breakpoints { 5215 print {$OUT} "Deleting all breakpoints...\n"; 5216 5217 # %had_breakpoints lists every file that had at least one 5218 # breakpoint in it. 5219 for my $fn ( keys %had_breakpoints ) { 5220 5221 # Switch to the desired file temporarily. 5222 local *dbline = $main::{ '_<' . $fn }; 5223 5224 $max = $#dbline; 5225 5226 # For all lines in this file ... 5227 for my $i (1 .. $max) { 5228 5229 # If there's a breakpoint or action on this line ... 5230 if ( defined $dbline{$i} ) { 5231 5232 # ... remove the breakpoint. 5233 $dbline{$i} =~ s/\A[^\0]+//; 5234 if ( $dbline{$i} =~ s/\A\0?\z// ) { 5235 # Remove the entry altogether if no action is there. 5236 _remove_breakpoint_entry($fn, $i); 5237 } 5238 } ## end if (defined $dbline{$i... 5239 } ## end for $i (1 .. $max) 5240 5241 # If, after we turn off the "there were breakpoints in this file" 5242 # bit, the entry in %had_breakpoints for this file is zero, 5243 # we should remove this file from the hash. 5244 if ( not $had_breakpoints{$fn} &= (~1) ) { 5245 delete $had_breakpoints{$fn}; 5246 } 5247 } ## end for my $fn (keys %had_breakpoints) 5248 5249 # Kill off all the other breakpoints that are waiting for files that 5250 # haven't been loaded yet. 5251 undef %postponed; 5252 undef %postponed_file; 5253 undef %break_on_load; 5254 5255 return; 5256} 5257 5258sub _delete_breakpoint_from_line { 5259 my ($i) = @_; 5260 5261 # Woops. This line wasn't breakable at all. 5262 die "Line $i not breakable.\n" if $dbline[$i] == 0; 5263 5264 # Kill the condition, but leave any action. 5265 $dbline{$i} =~ s/\A[^\0]*//; 5266 5267 # Remove the entry entirely if there's no action left. 5268 if ($dbline{$i} eq '') { 5269 _remove_breakpoint_entry($filename, $i); 5270 } 5271 5272 return; 5273} 5274 5275sub delete_breakpoint { 5276 my $i = shift; 5277 5278 # If we got a line, delete just that one. 5279 if ( defined($i) ) { 5280 _delete_breakpoint_from_line($i); 5281 } 5282 # No line; delete them all. 5283 else { 5284 _delete_all_breakpoints(); 5285 } 5286 5287 return; 5288} 5289 5290=head3 cmd_stop (command) 5291 5292This is meant to be part of the new command API, but it isn't called or used 5293anywhere else in the debugger. XXX It is probably meant for use in development 5294of new commands. 5295 5296=cut 5297 5298sub cmd_stop { # As on ^C, but not signal-safy. 5299 $signal = 1; 5300} 5301 5302=head3 C<cmd_e> - threads 5303 5304Display the current thread id: 5305 5306 e 5307 5308This could be how (when implemented) to send commands to this thread id (e cmd) 5309or that thread id (e tid cmd). 5310 5311=cut 5312 5313sub cmd_e { 5314 my $cmd = shift; 5315 my $line = shift; 5316 unless (exists($INC{'threads.pm'})) { 5317 print "threads not loaded($ENV{PERL5DB_THREADED}) 5318 please run the debugger with PERL5DB_THREADED=1 set in the environment\n"; 5319 } else { 5320 my $tid = threads->tid; 5321 print "thread id: $tid\n"; 5322 } 5323} ## end sub cmd_e 5324 5325=head3 C<cmd_E> - list of thread ids 5326 5327Display the list of available thread ids: 5328 5329 E 5330 5331This could be used (when implemented) to send commands to all threads (E cmd). 5332 5333=cut 5334 5335sub cmd_E { 5336 my $cmd = shift; 5337 my $line = shift; 5338 unless (exists($INC{'threads.pm'})) { 5339 print "threads not loaded($ENV{PERL5DB_THREADED}) 5340 please run the debugger with PERL5DB_THREADED=1 set in the environment\n"; 5341 } else { 5342 my $tid = threads->tid; 5343 print "thread ids: ".join(', ', 5344 map { ($tid == $_->tid ? '<'.$_->tid.'>' : $_->tid) } threads->list 5345 )."\n"; 5346 } 5347} ## end sub cmd_E 5348 5349=head3 C<cmd_h> - help command (command) 5350 5351Does the work of either 5352 5353=over 4 5354 5355=item * 5356 5357Showing all the debugger help 5358 5359=item * 5360 5361Showing help for a specific command 5362 5363=back 5364 5365=cut 5366 5367use vars qw($help); 5368use vars qw($summary); 5369 5370sub cmd_h { 5371 my $cmd = shift; 5372 5373 # If we have no operand, assume null. 5374 my $line = shift || ''; 5375 5376 # 'h h'. Print the long-format help. 5377 if ( $line =~ /\Ah\s*\z/ ) { 5378 print_help($help); 5379 } 5380 5381 # 'h <something>'. Search for the command and print only its help. 5382 elsif ( my ($asked) = $line =~ /\A(\S.*)\z/ ) { 5383 5384 # support long commands; otherwise bogus errors 5385 # happen when you ask for h on <CR> for example 5386 my $qasked = quotemeta($asked); # for searching; we don't 5387 # want to use it as a pattern. 5388 # XXX: finds CR but not <CR> 5389 5390 # Search the help string for the command. 5391 if ( 5392 $help =~ /^ # Start of a line 5393 <? # Optional '<' 5394 (?:[IB]<) # Optional markup 5395 $qasked # The requested command 5396 /mx 5397 ) 5398 { 5399 5400 # It's there; pull it out and print it. 5401 while ( 5402 $help =~ /^ 5403 (<? # Optional '<' 5404 (?:[IB]<) # Optional markup 5405 $qasked # The command 5406 ([\s\S]*?) # Description line(s) 5407 \n) # End of last description line 5408 (?!\s) # Next line not starting with 5409 # whitespace 5410 /mgx 5411 ) 5412 { 5413 print_help($1); 5414 } 5415 } 5416 5417 # Not found; not a debugger command. 5418 else { 5419 print_help("B<$asked> is not a debugger command.\n"); 5420 } 5421 } ## end elsif ($line =~ /^(\S.*)$/) 5422 5423 # 'h' - print the summary help. 5424 else { 5425 print_help($summary); 5426 } 5427} ## end sub cmd_h 5428 5429=head3 C<cmd_i> - inheritance display 5430 5431Display the (nested) parentage of the module or object given. 5432 5433=cut 5434 5435sub cmd_i { 5436 my $cmd = shift; 5437 my $line = shift; 5438 foreach my $isa ( split( /\s+/, $line ) ) { 5439 $evalarg = $isa; 5440 # The &-call is here to ascertain the mutability of @_. 5441 ($isa) = &DB::eval; 5442 no strict 'refs'; 5443 print join( 5444 ', ', 5445 map { 5446 "$_" 5447 . ( 5448 defined( ${"$_\::VERSION"} ) 5449 ? ' ' . ${"$_\::VERSION"} 5450 : undef ) 5451 } @{mro::get_linear_isa(ref($isa) || $isa)} 5452 ); 5453 print "\n"; 5454 } 5455} ## end sub cmd_i 5456 5457=head3 C<cmd_l> - list lines (command) 5458 5459Most of the command is taken up with transforming all the different line 5460specification syntaxes into 'start-stop'. After that is done, the command 5461runs a loop over C<@dbline> for the specified range of lines. It handles 5462the printing of each line and any markers (C<==E<gt>> for current line, 5463C<b> for break on this line, C<a> for action on this line, C<:> for this 5464line breakable). 5465 5466We save the last line listed in the C<$start> global for further listing 5467later. 5468 5469=cut 5470 5471sub _min { 5472 my $min = shift; 5473 foreach my $v (@_) { 5474 if ($min > $v) { 5475 $min = $v; 5476 } 5477 } 5478 return $min; 5479} 5480 5481sub _max { 5482 my $max = shift; 5483 foreach my $v (@_) { 5484 if ($max < $v) { 5485 $max = $v; 5486 } 5487 } 5488 return $max; 5489} 5490 5491sub _minify_to_max { 5492 my $ref = shift; 5493 5494 $$ref = _min($$ref, $max); 5495 5496 return; 5497} 5498 5499sub _cmd_l_handle_var_name { 5500 my $var_name = shift; 5501 5502 $evalarg = $var_name; 5503 5504 my ($s) = DB::eval(); 5505 5506 # Ooops. Bad scalar. 5507 if ($@) { 5508 print {$OUT} "Error: $@\n"; 5509 next CMD; 5510 } 5511 5512 # Good scalar. If it's a reference, find what it points to. 5513 $s = CvGV_name($s); 5514 print {$OUT} "Interpreted as: $1 $s\n"; 5515 $line = "$1 $s"; 5516 5517 # Call self recursively to really do the command. 5518 return _cmd_l_main( $s ); 5519} 5520 5521sub _cmd_l_handle_subname { 5522 5523 my $s = $subname; 5524 5525 # De-Perl4. 5526 $subname =~ s/\'/::/; 5527 5528 # Put it in this package unless it starts with ::. 5529 $subname = $package . "::" . $subname unless $subname =~ /::/; 5530 5531 # Put it in CORE::GLOBAL if t doesn't start with :: and 5532 # it doesn't live in this package and it lives in CORE::GLOBAL. 5533 $subname = "CORE::GLOBAL::$s" 5534 if not defined &$subname 5535 and $s !~ /::/ 5536 and defined &{"CORE::GLOBAL::$s"}; 5537 5538 # Put leading '::' names into 'main::'. 5539 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::"; 5540 5541 # Get name:start-stop from find_sub, and break this up at 5542 # colons. 5543 my @pieces = split( /:/, find_sub($subname) || $sub{$subname} ); 5544 5545 # Pull off start-stop. 5546 my $subrange = pop @pieces; 5547 5548 # If the name contained colons, the split broke it up. 5549 # Put it back together. 5550 $file = join( ':', @pieces ); 5551 5552 # If we're not in that file, switch over to it. 5553 if ( $file ne $filename ) { 5554 if (! $slave_editor) { 5555 print {$OUT} "Switching to file '$file'.\n"; 5556 } 5557 5558 # Switch debugger's magic structures. 5559 *dbline = $main::{ '_<' . $file }; 5560 $max = $#dbline; 5561 $filename = $file; 5562 } ## end if ($file ne $filename) 5563 5564 # Subrange is 'start-stop'. If this is less than a window full, 5565 # swap it to 'start+', which will list a window from the start point. 5566 if ($subrange) { 5567 if ( eval($subrange) < -$window ) { 5568 $subrange =~ s/-.*/+/; 5569 } 5570 5571 # Call self recursively to list the range. 5572 return _cmd_l_main( $subrange ); 5573 } ## end if ($subrange) 5574 5575 # Couldn't find it. 5576 else { 5577 print {$OUT} "Subroutine $subname not found.\n"; 5578 return; 5579 } 5580} 5581 5582sub _cmd_l_empty { 5583 # Compute new range to list. 5584 $incr = $window - 1; 5585 5586 # Recurse to do it. 5587 return _cmd_l_main( $start . '-' . ( $start + $incr ) ); 5588} 5589 5590sub _cmd_l_plus { 5591 my ($new_start, $new_incr) = @_; 5592 5593 # Don't reset start for 'l +nnn'. 5594 $start = $new_start if $new_start; 5595 5596 # Increment for list. Use window size if not specified. 5597 # (Allows 'l +' to work.) 5598 $incr = $new_incr || ($window - 1); 5599 5600 # Create a line range we'll understand, and recurse to do it. 5601 return _cmd_l_main( $start . '-' . ( $start + $incr ) ); 5602} 5603 5604sub _cmd_l_calc_initial_end_and_i { 5605 my ($spec, $start_match, $end_match) = @_; 5606 5607 # Determine end point; use end of file if not specified. 5608 my $end = ( !defined $start_match ) ? $max : 5609 ( $end_match ? $end_match : $start_match ); 5610 5611 # Go on to the end, and then stop. 5612 _minify_to_max(\$end); 5613 5614 # Determine start line. 5615 my $i = $start_match; 5616 5617 if ($i eq '.') { 5618 $i = $spec; 5619 } 5620 5621 $i = _max($i, 1); 5622 5623 $incr = $end - $i; 5624 5625 return ($end, $i); 5626} 5627 5628sub _cmd_l_range { 5629 my ($spec, $current_line, $start_match, $end_match) = @_; 5630 5631 my ($end, $i) = 5632 _cmd_l_calc_initial_end_and_i($spec, $start_match, $end_match); 5633 5634 # If we're running under a slave editor, force it to show the lines. 5635 if ($slave_editor) { 5636 print {$OUT} "\032\032$filename:$i:0\n"; 5637 $i = $end; 5638 } 5639 # We're doing it ourselves. We want to show the line and special 5640 # markers for: 5641 # - the current line in execution 5642 # - whether a line is breakable or not 5643 # - whether a line has a break or not 5644 # - whether a line has an action or not 5645 else { 5646 I_TO_END: 5647 for ( ; $i <= $end ; $i++ ) { 5648 5649 # Check for breakpoints and actions. 5650 my ( $stop, $action ); 5651 if ($dbline{$i}) { 5652 ( $stop, $action ) = split( /\0/, $dbline{$i} ); 5653 } 5654 5655 # ==> if this is the current line in execution, 5656 # : if it's breakable. 5657 my $arrow = 5658 ( $i == $current_line and $filename eq $filename_ini ) 5659 ? '==>' 5660 : ( $dbline[$i] + 0 ? ':' : ' ' ); 5661 5662 # Add break and action indicators. 5663 $arrow .= 'b' if $stop; 5664 $arrow .= 'a' if $action; 5665 5666 # Print the line. 5667 print {$OUT} "$i$arrow\t", $dbline[$i]; 5668 5669 # Move on to the next line. Drop out on an interrupt. 5670 if ($signal) { 5671 $i++; 5672 last I_TO_END; 5673 } 5674 } ## end for (; $i <= $end ; $i++) 5675 5676 # Line the prompt up; print a newline if the last line listed 5677 # didn't have a newline. 5678 if ($dbline[ $i - 1 ] !~ /\n\z/) { 5679 print {$OUT} "\n"; 5680 } 5681 } ## end else [ if ($slave_editor) 5682 5683 # Save the point we last listed to in case another relative 'l' 5684 # command is desired. Don't let it run off the end. 5685 $start = $i; 5686 _minify_to_max(\$start); 5687 5688 return; 5689} 5690 5691sub _cmd_l_main { 5692 my $spec = shift; 5693 5694 # If this is '-something', delete any spaces after the dash. 5695 $spec =~ s/\A-\s*\z/-/; 5696 5697 # If the line is '$something', assume this is a scalar containing a 5698 # line number. 5699 # Set up for DB::eval() - evaluate in *user* context. 5700 if ( my ($var_name) = $spec =~ /\A(\$.*)/s ) { 5701 return _cmd_l_handle_var_name($var_name); 5702 } 5703 # l name. Try to find a sub by that name. 5704 elsif ( ($subname) = $spec =~ /\A([\':A-Za-z_][\':\w]*(?:\[.*\])?)/s ) { 5705 return _cmd_l_handle_subname(); 5706 } 5707 # Bare 'l' command. 5708 elsif ( $spec !~ /\S/ ) { 5709 return _cmd_l_empty(); 5710 } 5711 # l [start]+number_of_lines 5712 elsif ( my ($new_start, $new_incr) = $spec =~ /\A(\d*)\+(\d*)\z/ ) { 5713 return _cmd_l_plus($new_start, $new_incr); 5714 } 5715 # l start-stop or l start,stop 5716 elsif (my ($s, $e) = $spec =~ /^(?:(-?[\d\$\.]+)(?:[-,]([\d\$\.]+))?)?/ ) { 5717 return _cmd_l_range($spec, $line, $s, $e); 5718 } 5719 5720 return; 5721} ## end sub cmd_l 5722 5723sub cmd_l { 5724 my (undef, $line) = @_; 5725 5726 return _cmd_l_main($line); 5727} 5728 5729=head3 C<cmd_L> - list breakpoints, actions, and watch expressions (command) 5730 5731To list breakpoints, the command has to look determine where all of them are 5732first. It starts a C<%had_breakpoints>, which tells us what all files have 5733breakpoints and/or actions. For each file, we switch the C<*dbline> glob (the 5734magic source and breakpoint data structures) to the file, and then look 5735through C<%dbline> for lines with breakpoints and/or actions, listing them 5736out. We look through C<%postponed> not-yet-compiled subroutines that have 5737breakpoints, and through C<%postponed_file> for not-yet-C<require>'d files 5738that have breakpoints. 5739 5740Watchpoints are simpler: we just list the entries in C<@to_watch>. 5741 5742=cut 5743 5744sub _cmd_L_calc_arg { 5745 # If no argument, list everything. Pre-5.8.0 version always lists 5746 # everything 5747 my $arg = shift || 'abw'; 5748 if ($CommandSet ne '580') 5749 { 5750 $arg = 'abw'; 5751 } 5752 5753 return $arg; 5754} 5755 5756sub _cmd_L_calc_wanted_flags { 5757 my $arg = _cmd_L_calc_arg(shift); 5758 5759 return (map { index($arg, $_) >= 0 ? 1 : 0 } qw(a b w)); 5760} 5761 5762 5763sub _cmd_L_handle_breakpoints { 5764 my ($handle_db_line) = @_; 5765 5766 BREAKPOINTS_SCAN: 5767 # Look in all the files with breakpoints... 5768 for my $file ( keys %had_breakpoints ) { 5769 5770 # Temporary switch to this file. 5771 local *dbline = $main::{ '_<' . $file }; 5772 5773 # Set up to look through the whole file. 5774 $max = $#dbline; 5775 my $was; # Flag: did we print something 5776 # in this file? 5777 5778 # For each line in the file ... 5779 for my $i (1 .. $max) { 5780 5781 # We've got something on this line. 5782 if ( defined $dbline{$i} ) { 5783 5784 # Print the header if we haven't. 5785 if (not $was++) { 5786 print {$OUT} "$file:\n"; 5787 } 5788 5789 # Print the line. 5790 print {$OUT} " $i:\t", $dbline[$i]; 5791 5792 $handle_db_line->($dbline{$i}); 5793 5794 # Quit if the user hit interrupt. 5795 if ($signal) { 5796 last BREAKPOINTS_SCAN; 5797 } 5798 } ## end if (defined $dbline{$i... 5799 } ## end for my $i (1 .. $max) 5800 } ## end for my $file (keys %had_breakpoints) 5801 5802 return; 5803} 5804 5805sub _cmd_L_handle_postponed_breakpoints { 5806 my ($handle_db_line) = @_; 5807 5808 print {$OUT} "Postponed breakpoints in files:\n"; 5809 5810 POSTPONED_SCANS: 5811 for my $file ( keys %postponed_file ) { 5812 my $db = $postponed_file{$file}; 5813 print {$OUT} " $file:\n"; 5814 for my $line ( sort { $a <=> $b } keys %$db ) { 5815 print {$OUT} " $line:\n"; 5816 5817 $handle_db_line->($db->{$line}); 5818 5819 if ($signal) { 5820 last POSTPONED_SCANS; 5821 } 5822 } 5823 if ($signal) { 5824 last POSTPONED_SCANS; 5825 } 5826 } 5827 5828 return; 5829} 5830 5831 5832sub cmd_L { 5833 my $cmd = shift; 5834 5835 my ($action_wanted, $break_wanted, $watch_wanted) = 5836 _cmd_L_calc_wanted_flags(shift); 5837 5838 my $handle_db_line = sub { 5839 my ($l) = @_; 5840 5841 my ( $stop, $action ) = split( /\0/, $l ); 5842 5843 if ($stop and $break_wanted) { 5844 print {$OUT} " break if (", $stop, ")\n" 5845 } 5846 5847 if ($action && $action_wanted) { 5848 print {$OUT} " action: ", $action, "\n" 5849 } 5850 5851 return; 5852 }; 5853 5854 # Breaks and actions are found together, so we look in the same place 5855 # for both. 5856 if ( $break_wanted or $action_wanted ) { 5857 _cmd_L_handle_breakpoints($handle_db_line); 5858 } 5859 5860 # Look for breaks in not-yet-compiled subs: 5861 if ( %postponed and $break_wanted ) { 5862 print {$OUT} "Postponed breakpoints in subroutines:\n"; 5863 my $subname; 5864 SUBS_SCAN: 5865 for $subname ( keys %postponed ) { 5866 print {$OUT} " $subname\t$postponed{$subname}\n"; 5867 if ($signal) { 5868 last SUBS_SCAN; 5869 } 5870 } 5871 } ## end if (%postponed and $break_wanted) 5872 5873 # Find files that have not-yet-loaded breaks: 5874 my @have = map { # Combined keys 5875 keys %{ $postponed_file{$_} } 5876 } keys %postponed_file; 5877 5878 # If there are any, list them. 5879 if ( @have and ( $break_wanted or $action_wanted ) ) { 5880 _cmd_L_handle_postponed_breakpoints($handle_db_line); 5881 } ## end if (@have and ($break_wanted... 5882 5883 if ( %break_on_load and $break_wanted ) { 5884 print {$OUT} "Breakpoints on load:\n"; 5885 BREAK_ON_LOAD: for my $filename ( keys %break_on_load ) { 5886 print {$OUT} " $filename\n"; 5887 last BREAK_ON_LOAD if $signal; 5888 } 5889 } ## end if (%break_on_load and... 5890 5891 if ($watch_wanted and ( $trace & 2 )) { 5892 print {$OUT} "Watch-expressions:\n" if @to_watch; 5893 TO_WATCH: for my $expr (@to_watch) { 5894 print {$OUT} " $expr\n"; 5895 last TO_WATCH if $signal; 5896 } 5897 } 5898 5899 return; 5900} ## end sub cmd_L 5901 5902=head3 C<cmd_M> - list modules (command) 5903 5904Just call C<list_modules>. 5905 5906=cut 5907 5908sub cmd_M { 5909 list_modules(); 5910 5911 return; 5912} 5913 5914=head3 C<cmd_o> - options (command) 5915 5916If this is just C<o> by itself, we list the current settings via 5917C<dump_option>. If there's a nonblank value following it, we pass that on to 5918C<parse_options> for processing. 5919 5920=cut 5921 5922sub cmd_o { 5923 my $cmd = shift; 5924 my $opt = shift || ''; # opt[=val] 5925 5926 # Nonblank. Try to parse and process. 5927 if ( $opt =~ /^(\S.*)/ ) { 5928 parse_options($1); 5929 } 5930 5931 # Blank. List the current option settings. 5932 else { 5933 for (@options) { 5934 dump_option($_); 5935 } 5936 } 5937} ## end sub cmd_o 5938 5939=head3 C<cmd_O> - nonexistent in 5.8.x (command) 5940 5941Advises the user that the O command has been renamed. 5942 5943=cut 5944 5945sub cmd_O { 5946 print $OUT "The old O command is now the o command.\n"; # hint 5947 print $OUT "Use 'h' to get current command help synopsis or\n"; # 5948 print $OUT "use 'o CommandSet=pre580' to revert to old usage\n"; # 5949} 5950 5951=head3 C<cmd_v> - view window (command) 5952 5953Uses the C<$preview> variable set in the second C<BEGIN> block (q.v.) to 5954move back a few lines to list the selected line in context. Uses C<cmd_l> 5955to do the actual listing after figuring out the range of line to request. 5956 5957=cut 5958 5959use vars qw($preview); 5960 5961sub cmd_v { 5962 my $cmd = shift; 5963 my $line = shift; 5964 5965 # Extract the line to list around. (Astute readers will have noted that 5966 # this pattern will match whether or not a numeric line is specified, 5967 # which means that we'll always enter this loop (though a non-numeric 5968 # argument results in no action at all)). 5969 if ( $line =~ /^(\d*)$/ ) { 5970 5971 # Total number of lines to list (a windowful). 5972 $incr = $window - 1; 5973 5974 # Set the start to the argument given (if there was one). 5975 $start = $1 if $1; 5976 5977 # Back up by the context amount. 5978 $start -= $preview; 5979 5980 # Put together a linespec that cmd_l will like. 5981 $line = $start . '-' . ( $start + $incr ); 5982 5983 # List the lines. 5984 cmd_l( 'l', $line ); 5985 } ## end if ($line =~ /^(\d*)$/) 5986} ## end sub cmd_v 5987 5988=head3 C<cmd_w> - add a watch expression (command) 5989 5990The 5.8 version of this command adds a watch expression if one is specified; 5991it does nothing if entered with no operands. 5992 5993We extract the expression, save it, evaluate it in the user's context, and 5994save the value. We'll re-evaluate it each time the debugger passes a line, 5995and will stop (see the code at the top of the command loop) if the value 5996of any of the expressions changes. 5997 5998=cut 5999 6000sub _add_watch_expr { 6001 my $expr = shift; 6002 6003 # ... save it. 6004 push @to_watch, $expr; 6005 6006 # Parameterize DB::eval and call it to get the expression's value 6007 # in the user's context. This version can handle expressions which 6008 # return a list value. 6009 $evalarg = $expr; 6010 # The &-call is here to ascertain the mutability of @_. 6011 my ($val) = join( ' ', &DB::eval); 6012 $val = ( defined $val ) ? "'$val'" : 'undef'; 6013 6014 # Save the current value of the expression. 6015 push @old_watch, $val; 6016 6017 # We are now watching expressions. 6018 $trace |= 2; 6019 6020 return; 6021} 6022 6023sub cmd_w { 6024 my $cmd = shift; 6025 6026 # Null expression if no arguments. 6027 my $expr = shift || ''; 6028 6029 # If expression is not null ... 6030 if ( $expr =~ /\A\S/ ) { 6031 _add_watch_expr($expr); 6032 } ## end if ($expr =~ /^(\S.*)/) 6033 6034 # You have to give one to get one. 6035 else { 6036 print $OUT "Adding a watch-expression requires an expression\n"; # hint 6037 } 6038 6039 return; 6040} 6041 6042=head3 C<cmd_W> - delete watch expressions (command) 6043 6044This command accepts either a watch expression to be removed from the list 6045of watch expressions, or C<*> to delete them all. 6046 6047If C<*> is specified, we simply empty the watch expression list and the 6048watch expression value list. We also turn off the bit that says we've got 6049watch expressions. 6050 6051If an expression (or partial expression) is specified, we pattern-match 6052through the expressions and remove the ones that match. We also discard 6053the corresponding values. If no watch expressions are left, we turn off 6054the I<watching expressions> bit. 6055 6056=cut 6057 6058sub cmd_W { 6059 my $cmd = shift; 6060 my $expr = shift || ''; 6061 6062 # Delete them all. 6063 if ( $expr eq '*' ) { 6064 6065 # Not watching now. 6066 $trace &= ~2; 6067 6068 print $OUT "Deleting all watch expressions ...\n"; 6069 6070 # And all gone. 6071 @to_watch = @old_watch = (); 6072 } 6073 6074 # Delete one of them. 6075 elsif ( $expr =~ /^(\S.*)/ ) { 6076 6077 # Where we are in the list. 6078 my $i_cnt = 0; 6079 6080 # For each expression ... 6081 foreach (@to_watch) { 6082 my $val = $to_watch[$i_cnt]; 6083 6084 # Does this one match the command argument? 6085 if ( $val eq $expr ) { # =~ m/^\Q$i$/) { 6086 # Yes. Turn it off, and its value too. 6087 splice( @to_watch, $i_cnt, 1 ); 6088 splice( @old_watch, $i_cnt, 1 ); 6089 } 6090 $i_cnt++; 6091 } ## end foreach (@to_watch) 6092 6093 # We don't bother to turn watching off because 6094 # a) we don't want to stop calling watchfunction() it it exists 6095 # b) foreach over a null list doesn't do anything anyway 6096 6097 } ## end elsif ($expr =~ /^(\S.*)/) 6098 6099 # No command arguments entered. 6100 else { 6101 print $OUT 6102 "Deleting a watch-expression requires an expression, or '*' for all\n" 6103 ; # hint 6104 } 6105} ## end sub cmd_W 6106 6107### END of the API section 6108 6109=head1 SUPPORT ROUTINES 6110 6111These are general support routines that are used in a number of places 6112throughout the debugger. 6113 6114=head2 save 6115 6116save() saves the user's versions of globals that would mess us up in C<@saved>, 6117and installs the versions we like better. 6118 6119=cut 6120 6121sub save { 6122 6123 # Save eval failure, command failure, extended OS error, output field 6124 # separator, input record separator, output record separator and 6125 # the warning setting. 6126 @saved = ( $@, $!, $^E, $,, $/, $\, $^W ); 6127 6128 $, = ""; # output field separator is null string 6129 $/ = "\n"; # input record separator is newline 6130 $\ = ""; # output record separator is null string 6131 $^W = 0; # warnings are off 6132} ## end sub save 6133 6134=head2 C<print_lineinfo> - show where we are now 6135 6136print_lineinfo prints whatever it is that it is handed; it prints it to the 6137C<$LINEINFO> filehandle instead of just printing it to STDOUT. This allows 6138us to feed line information to a slave editor without messing up the 6139debugger output. 6140 6141=cut 6142 6143sub print_lineinfo { 6144 6145 # Make the terminal sensible if we're not the primary debugger. 6146 resetterm(1) if $LINEINFO eq $OUT and $term_pid != $$; 6147 local $\ = ''; 6148 local $, = ''; 6149 print $LINEINFO @_; 6150} ## end sub print_lineinfo 6151 6152=head2 C<postponed_sub> 6153 6154Handles setting postponed breakpoints in subroutines once they're compiled. 6155For breakpoints, we use C<DB::find_sub> to locate the source file and line 6156range for the subroutine, then mark the file as having a breakpoint, 6157temporarily switch the C<*dbline> glob over to the source file, and then 6158search the given range of lines to find a breakable line. If we find one, 6159we set the breakpoint on it, deleting the breakpoint from C<%postponed>. 6160 6161=cut 6162 6163# The following takes its argument via $evalarg to preserve current @_ 6164 6165sub postponed_sub { 6166 6167 # Get the subroutine name. 6168 my $subname = shift; 6169 6170 # If this is a 'break +<n> if <condition>' ... 6171 if ( $postponed{$subname} =~ s/^break\s([+-]?\d+)\s+if\s// ) { 6172 6173 # If there's no offset, use '+0'. 6174 my $offset = $1 || 0; 6175 6176 # find_sub's value is 'fullpath-filename:start-stop'. It's 6177 # possible that the filename might have colons in it too. 6178 my ( $file, $i ) = ( find_sub($subname) =~ /^(.*):(\d+)-.*$/ ); 6179 if ($i) { 6180 6181 # We got the start line. Add the offset '+<n>' from 6182 # $postponed{subname}. 6183 $i += $offset; 6184 6185 # Switch to the file this sub is in, temporarily. 6186 local *dbline = $main::{ '_<' . $file }; 6187 6188 # No warnings, please. 6189 local $^W = 0; # != 0 is magical below 6190 6191 # This file's got a breakpoint in it. 6192 $had_breakpoints{$file} |= 1; 6193 6194 # Last line in file. 6195 $max = $#dbline; 6196 6197 # Search forward until we hit a breakable line or get to 6198 # the end of the file. 6199 ++$i until $dbline[$i] != 0 or $i >= $max; 6200 6201 # Copy the breakpoint in and delete it from %postponed. 6202 $dbline{$i} = delete $postponed{$subname}; 6203 } ## end if ($i) 6204 6205 # find_sub didn't find the sub. 6206 else { 6207 local $\ = ''; 6208 print $OUT "Subroutine $subname not found.\n"; 6209 } 6210 return; 6211 } ## end if ($postponed{$subname... 6212 elsif ( $postponed{$subname} eq 'compile' ) { $signal = 1 } 6213 6214 #print $OUT "In postponed_sub for '$subname'.\n"; 6215} ## end sub postponed_sub 6216 6217=head2 C<postponed> 6218 6219Called after each required file is compiled, but before it is executed; 6220also called if the name of a just-compiled subroutine is a key of 6221C<%postponed>. Propagates saved breakpoints (from C<b compile>, C<b load>, 6222etc.) into the just-compiled code. 6223 6224If this is a C<require>'d file, the incoming parameter is the glob 6225C<*{"_<$filename"}>, with C<$filename> the name of the C<require>'d file. 6226 6227If it's a subroutine, the incoming parameter is the subroutine name. 6228 6229=cut 6230 6231sub postponed { 6232 6233 # If there's a break, process it. 6234 if ($ImmediateStop) { 6235 6236 # Right, we've stopped. Turn it off. 6237 $ImmediateStop = 0; 6238 6239 # Enter the command loop when DB::DB gets called. 6240 $signal = 1; 6241 } 6242 6243 # If this is a subroutine, let postponed_sub() deal with it. 6244 if (ref(\$_[0]) ne 'GLOB') { 6245 return postponed_sub(@_); 6246 } 6247 6248 # Not a subroutine. Deal with the file. 6249 local *dbline = shift; 6250 my $filename = $dbline; 6251 $filename =~ s/^_<//; 6252 local $\ = ''; 6253 $signal = 1, print $OUT "'$filename' loaded...\n" 6254 if $break_on_load{$filename}; 6255 print_lineinfo( ' ' x $stack_depth, "Package $filename.\n" ) if $frame; 6256 6257 # Do we have any breakpoints to put in this file? 6258 return unless $postponed_file{$filename}; 6259 6260 # Yes. Mark this file as having breakpoints. 6261 $had_breakpoints{$filename} |= 1; 6262 6263 # "Cannot be done: insufficient magic" - we can't just put the 6264 # breakpoints saved in %postponed_file into %dbline by assigning 6265 # the whole hash; we have to do it one item at a time for the 6266 # breakpoints to be set properly. 6267 #%dbline = %{$postponed_file{$filename}}; 6268 6269 # Set the breakpoints, one at a time. 6270 my $key; 6271 6272 for $key ( keys %{ $postponed_file{$filename} } ) { 6273 6274 # Stash the saved breakpoint into the current file's magic line array. 6275 $dbline{$key} = ${ $postponed_file{$filename} }{$key}; 6276 } 6277 6278 # This file's been compiled; discard the stored breakpoints. 6279 delete $postponed_file{$filename}; 6280 6281} ## end sub postponed 6282 6283=head2 C<dumpit> 6284 6285C<dumpit> is the debugger's wrapper around dumpvar.pl. 6286 6287It gets a filehandle (to which C<dumpvar.pl>'s output will be directed) and 6288a reference to a variable (the thing to be dumped) as its input. 6289 6290The incoming filehandle is selected for output (C<dumpvar.pl> is printing to 6291the currently-selected filehandle, thank you very much). The current 6292values of the package globals C<$single> and C<$trace> are backed up in 6293lexicals, and they are turned off (this keeps the debugger from trying 6294to single-step through C<dumpvar.pl> (I think.)). C<$frame> is localized to 6295preserve its current value and it is set to zero to prevent entry/exit 6296messages from printing, and C<$doret> is localized as well and set to -2 to 6297prevent return values from being shown. 6298 6299C<dumpit()> then checks to see if it needs to load C<dumpvar.pl> and 6300tries to load it (note: if you have a C<dumpvar.pl> ahead of the 6301installed version in C<@INC>, yours will be used instead. Possible security 6302problem?). 6303 6304It then checks to see if the subroutine C<main::dumpValue> is now defined 6305it should have been defined by C<dumpvar.pl>). If it has, C<dumpit()> 6306localizes the globals necessary for things to be sane when C<main::dumpValue()> 6307is called, and picks up the variable to be dumped from the parameter list. 6308 6309It checks the package global C<%options> to see if there's a C<dumpDepth> 6310specified. If not, -1 is assumed; if so, the supplied value gets passed on to 6311C<dumpvar.pl>. This tells C<dumpvar.pl> where to leave off when dumping a 6312structure: -1 means dump everything. 6313 6314C<dumpValue()> is then called if possible; if not, C<dumpit()>just prints a 6315warning. 6316 6317In either case, C<$single>, C<$trace>, C<$frame>, and C<$doret> are restored 6318and we then return to the caller. 6319 6320=cut 6321 6322sub dumpit { 6323 6324 # Save the current output filehandle and switch to the one 6325 # passed in as the first parameter. 6326 my $savout = select(shift); 6327 6328 # Save current settings of $single and $trace, and then turn them off. 6329 my $osingle = $single; 6330 my $otrace = $trace; 6331 $single = $trace = 0; 6332 6333 # XXX Okay, what do $frame and $doret do, again? 6334 local $frame = 0; 6335 local $doret = -2; 6336 6337 # Load dumpvar.pl unless we've already got the sub we need from it. 6338 unless ( defined &main::dumpValue ) { 6339 do 'dumpvar.pl' or die $@; 6340 } 6341 6342 # If the load succeeded (or we already had dumpvalue()), go ahead 6343 # and dump things. 6344 if ( defined &main::dumpValue ) { 6345 local $\ = ''; 6346 local $, = ''; 6347 local $" = ' '; 6348 my $v = shift; 6349 my $maxdepth = shift || $option{dumpDepth}; 6350 $maxdepth = -1 unless defined $maxdepth; # -1 means infinite depth 6351 main::dumpValue( $v, $maxdepth ); 6352 } ## end if (defined &main::dumpValue) 6353 6354 # Oops, couldn't load dumpvar.pl. 6355 else { 6356 local $\ = ''; 6357 print $OUT "dumpvar.pl not available.\n"; 6358 } 6359 6360 # Reset $single and $trace to their old values. 6361 $single = $osingle; 6362 $trace = $otrace; 6363 6364 # Restore the old filehandle. 6365 select($savout); 6366} ## end sub dumpit 6367 6368=head2 C<print_trace> 6369 6370C<print_trace>'s job is to print a stack trace. It does this via the 6371C<dump_trace> routine, which actually does all the ferreting-out of the 6372stack trace data. C<print_trace> takes care of formatting it nicely and 6373printing it to the proper filehandle. 6374 6375Parameters: 6376 6377=over 4 6378 6379=item * 6380 6381The filehandle to print to. 6382 6383=item * 6384 6385How many frames to skip before starting trace. 6386 6387=item * 6388 6389How many frames to print. 6390 6391=item * 6392 6393A flag: if true, print a I<short> trace without filenames, line numbers, or arguments 6394 6395=back 6396 6397The original comment below seems to be noting that the traceback may not be 6398correct if this routine is called in a tied method. 6399 6400=cut 6401 6402# Tied method do not create a context, so may get wrong message: 6403 6404sub print_trace { 6405 local $\ = ''; 6406 my $fh = shift; 6407 6408 # If this is going to a slave editor, but we're not the primary 6409 # debugger, reset it first. 6410 resetterm(1) 6411 if $fh eq $LINEINFO # slave editor 6412 and $LINEINFO eq $OUT # normal output 6413 and $term_pid != $$; # not the primary 6414 6415 # Collect the actual trace information to be formatted. 6416 # This is an array of hashes of subroutine call info. 6417 my @sub = dump_trace( $_[0] + 1, $_[1] ); 6418 6419 # Grab the "short report" flag from @_. 6420 my $short = $_[2]; # Print short report, next one for sub name 6421 6422 # Run through the traceback info, format it, and print it. 6423 my $s; 6424 for my $i (0 .. $#sub) { 6425 6426 # Drop out if the user has lost interest and hit control-C. 6427 last if $signal; 6428 6429 # Set the separator so arrys print nice. 6430 local $" = ', '; 6431 6432 # Grab and stringify the arguments if they are there. 6433 my $args = 6434 defined $sub[$i]{args} 6435 ? "(@{ $sub[$i]{args} })" 6436 : ''; 6437 6438 # Shorten them up if $maxtrace says they're too long. 6439 $args = ( substr $args, 0, $maxtrace - 3 ) . '...' 6440 if length $args > $maxtrace; 6441 6442 # Get the file name. 6443 my $file = $sub[$i]{file}; 6444 6445 # Put in a filename header if short is off. 6446 $file = $file eq '-e' ? $file : "file '$file'" unless $short; 6447 6448 # Get the actual sub's name, and shorten to $maxtrace's requirement. 6449 $s = $sub[$i]{'sub'}; 6450 $s = ( substr $s, 0, $maxtrace - 3 ) . '...' if length $s > $maxtrace; 6451 6452 # Short report uses trimmed file and sub names. 6453 if ($short) { 6454 my $sub = @_ >= 4 ? $_[3] : $s; 6455 print $fh "$sub[$i]{context}=$sub$args from $file:$sub[$i]{line}\n"; 6456 } ## end if ($short) 6457 6458 # Non-short report includes full names. 6459 else { 6460 print $fh "$sub[$i]{context} = $s$args" 6461 . " called from $file" 6462 . " line $sub[$i]{line}\n"; 6463 } 6464 } ## end for my $i (0 .. $#sub) 6465} ## end sub print_trace 6466 6467=head2 dump_trace(skip[,count]) 6468 6469Actually collect the traceback information available via C<caller()>. It does 6470some filtering and cleanup of the data, but mostly it just collects it to 6471make C<print_trace()>'s job easier. 6472 6473C<skip> defines the number of stack frames to be skipped, working backwards 6474from the most current. C<count> determines the total number of frames to 6475be returned; all of them (well, the first 10^9) are returned if C<count> 6476is omitted. 6477 6478This routine returns a list of hashes, from most-recent to least-recent 6479stack frame. Each has the following keys and values: 6480 6481=over 4 6482 6483=item * C<context> - C<.> (null), C<$> (scalar), or C<@> (array) 6484 6485=item * C<sub> - subroutine name, or C<eval> information 6486 6487=item * C<args> - undef, or a reference to an array of arguments 6488 6489=item * C<file> - the file in which this item was defined (if any) 6490 6491=item * C<line> - the line on which it was defined 6492 6493=back 6494 6495=cut 6496 6497sub _dump_trace_calc_saved_single_arg 6498{ 6499 my ($nothard, $arg) = @_; 6500 6501 my $type; 6502 if ( not defined $arg ) { # undefined parameter 6503 return "undef"; 6504 } 6505 6506 elsif ( $nothard and tied $arg ) { # tied parameter 6507 return "tied"; 6508 } 6509 elsif ( $nothard and $type = ref $arg ) { # reference 6510 return "ref($type)"; 6511 } 6512 else { # can be stringified 6513 local $_ = 6514 "$arg"; # Safe to stringify now - should not call f(). 6515 6516 # Backslash any single-quotes or backslashes. 6517 s/([\'\\])/\\$1/g; 6518 6519 # Single-quote it unless it's a number or a colon-separated 6520 # name. 6521 s/(.*)/'$1'/s 6522 unless /^(?: -?[\d.]+ | \*[\w:]* )$/x; 6523 6524 # Turn high-bit characters into meta-whatever. 6525 s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg; 6526 6527 # Turn control characters into ^-whatever. 6528 s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg; 6529 6530 return $_; 6531 } 6532} 6533 6534sub _dump_trace_calc_save_args { 6535 my ($nothard) = @_; 6536 6537 return [ 6538 map { _dump_trace_calc_saved_single_arg($nothard, $_) } @args 6539 ]; 6540} 6541 6542sub dump_trace { 6543 6544 # How many levels to skip. 6545 my $skip = shift; 6546 6547 # How many levels to show. (1e9 is a cheap way of saying "all of them"; 6548 # it's unlikely that we'll have more than a billion stack frames. If you 6549 # do, you've got an awfully big machine...) 6550 my $count = shift || 1e9; 6551 6552 # We increment skip because caller(1) is the first level *back* from 6553 # the current one. Add $skip to the count of frames so we have a 6554 # simple stop criterion, counting from $skip to $count+$skip. 6555 $skip++; 6556 $count += $skip; 6557 6558 # These variables are used to capture output from caller(); 6559 my ( $p, $file, $line, $sub, $h, $context ); 6560 6561 my ( $e, $r, @sub, $args ); 6562 6563 # XXX Okay... why'd we do that? 6564 my $nothard = not $frame & 8; 6565 local $frame = 0; 6566 6567 # Do not want to trace this. 6568 my $otrace = $trace; 6569 $trace = 0; 6570 6571 # Start out at the skip count. 6572 # If we haven't reached the number of frames requested, and caller() is 6573 # still returning something, stay in the loop. (If we pass the requested 6574 # number of stack frames, or we run out - caller() returns nothing - we 6575 # quit. 6576 # Up the stack frame index to go back one more level each time. 6577 for ( 6578 my $i = $skip ; 6579 $i < $count 6580 and ( $p, $file, $line, $sub, $h, $context, $e, $r ) = caller($i) ; 6581 $i++ 6582 ) 6583 { 6584 6585 # Go through the arguments and save them for later. 6586 my $save_args = _dump_trace_calc_save_args($nothard); 6587 6588 # If context is true, this is array (@)context. 6589 # If context is false, this is scalar ($) context. 6590 # If neither, context isn't defined. (This is apparently a 'can't 6591 # happen' trap.) 6592 $context = $context ? '@' : ( defined $context ? "\$" : '.' ); 6593 6594 # if the sub has args ($h true), make an anonymous array of the 6595 # dumped args. 6596 $args = $h ? $save_args : undef; 6597 6598 # remove trailing newline-whitespace-semicolon-end of line sequence 6599 # from the eval text, if any. 6600 $e =~ s/\n\s*\;\s*\Z// if $e; 6601 6602 # Escape backslashed single-quotes again if necessary. 6603 $e =~ s/([\\\'])/\\$1/g if $e; 6604 6605 # if the require flag is true, the eval text is from a require. 6606 if ($r) { 6607 $sub = "require '$e'"; 6608 } 6609 6610 # if it's false, the eval text is really from an eval. 6611 elsif ( defined $r ) { 6612 $sub = "eval '$e'"; 6613 } 6614 6615 # If the sub is '(eval)', this is a block eval, meaning we don't 6616 # know what the eval'ed text actually was. 6617 elsif ( $sub eq '(eval)' ) { 6618 $sub = "eval {...}"; 6619 } 6620 6621 # Stick the collected information into @sub as an anonymous hash. 6622 push( 6623 @sub, 6624 { 6625 context => $context, 6626 sub => $sub, 6627 args => $args, 6628 file => $file, 6629 line => $line 6630 } 6631 ); 6632 6633 # Stop processing frames if the user hit control-C. 6634 last if $signal; 6635 } ## end for ($i = $skip ; $i < ... 6636 6637 # Restore the trace value again. 6638 $trace = $otrace; 6639 @sub; 6640} ## end sub dump_trace 6641 6642=head2 C<action()> 6643 6644C<action()> takes input provided as the argument to an add-action command, 6645either pre- or post-, and makes sure it's a complete command. It doesn't do 6646any fancy parsing; it just keeps reading input until it gets a string 6647without a trailing backslash. 6648 6649=cut 6650 6651sub action { 6652 my $action = shift; 6653 6654 while ( $action =~ s/\\$// ) { 6655 6656 # We have a backslash on the end. Read more. 6657 $action .= gets(); 6658 } ## end while ($action =~ s/\\$//) 6659 6660 # Return the assembled action. 6661 $action; 6662} ## end sub action 6663 6664=head2 unbalanced 6665 6666This routine mostly just packages up a regular expression to be used 6667to check that the thing it's being matched against has properly-matched 6668curly braces. 6669 6670Of note is the definition of the C<$balanced_brace_re> global via C<||=>, which 6671speeds things up by only creating the qr//'ed expression once; if it's 6672already defined, we don't try to define it again. A speed hack. 6673 6674=cut 6675 6676use vars qw($balanced_brace_re); 6677 6678sub unbalanced { 6679 6680 # I hate using globals! 6681 $balanced_brace_re ||= qr{ 6682 ^ \{ 6683 (?: 6684 (?> [^{}] + ) # Non-parens without backtracking 6685 | 6686 (??{ $balanced_brace_re }) # Group with matching parens 6687 ) * 6688 \} $ 6689 }x; 6690 return $_[0] !~ m/$balanced_brace_re/; 6691} ## end sub unbalanced 6692 6693=head2 C<gets()> 6694 6695C<gets()> is a primitive (very primitive) routine to read continuations. 6696It was devised for reading continuations for actions. 6697it just reads more input with C<readline()> and returns it. 6698 6699=cut 6700 6701sub gets { 6702 return DB::readline("cont: "); 6703} 6704 6705=head2 C<_db_system()> - handle calls to<system()> without messing up the debugger 6706 6707The C<system()> function assumes that it can just go ahead and use STDIN and 6708STDOUT, but under the debugger, we want it to use the debugger's input and 6709outout filehandles. 6710 6711C<_db_system()> socks away the program's STDIN and STDOUT, and then substitutes 6712the debugger's IN and OUT filehandles for them. It does the C<system()> call, 6713and then puts everything back again. 6714 6715=cut 6716 6717sub _db_system { 6718 6719 # We save, change, then restore STDIN and STDOUT to avoid fork() since 6720 # some non-Unix systems can do system() but have problems with fork(). 6721 open( SAVEIN, "<&STDIN" ) || db_warn("Can't save STDIN"); 6722 open( SAVEOUT, ">&STDOUT" ) || db_warn("Can't save STDOUT"); 6723 open( STDIN, "<&IN" ) || db_warn("Can't redirect STDIN"); 6724 open( STDOUT, ">&OUT" ) || db_warn("Can't redirect STDOUT"); 6725 6726 # XXX: using csh or tcsh destroys sigint retvals! 6727 system(@_); 6728 open( STDIN, "<&SAVEIN" ) || db_warn("Can't restore STDIN"); 6729 open( STDOUT, ">&SAVEOUT" ) || db_warn("Can't restore STDOUT"); 6730 close(SAVEIN); 6731 close(SAVEOUT); 6732 6733 # most of the $? crud was coping with broken cshisms 6734 if ( $? >> 8 ) { 6735 db_warn( "(Command exited ", ( $? >> 8 ), ")\n" ); 6736 } 6737 elsif ($?) { 6738 db_warn( 6739 "(Command died of SIG#", 6740 ( $? & 127 ), 6741 ( ( $? & 128 ) ? " -- core dumped" : "" ), 6742 ")", "\n" 6743 ); 6744 } ## end elsif ($?) 6745 6746 return $?; 6747 6748} ## end sub system 6749 6750*system = \&_db_system; 6751 6752=head1 TTY MANAGEMENT 6753 6754The subs here do some of the terminal management for multiple debuggers. 6755 6756=head2 setterm 6757 6758Top-level function called when we want to set up a new terminal for use 6759by the debugger. 6760 6761If the C<noTTY> debugger option was set, we'll either use the terminal 6762supplied (the value of the C<noTTY> option), or we'll use C<Term::Rendezvous> 6763to find one. If we're a forked debugger, we call C<resetterm> to try to 6764get a whole new terminal if we can. 6765 6766In either case, we set up the terminal next. If the C<ReadLine> option was 6767true, we'll get a C<Term::ReadLine> object for the current terminal and save 6768the appropriate attributes. We then 6769 6770=cut 6771 6772use vars qw($ornaments); 6773use vars qw($rl_attribs); 6774 6775sub setterm { 6776 6777 # Load Term::Readline, but quietly; don't debug it and don't trace it. 6778 local $frame = 0; 6779 local $doret = -2; 6780 require Term::ReadLine; 6781 6782 # If noTTY is set, but we have a TTY name, go ahead and hook up to it. 6783 if ($notty) { 6784 if ($tty) { 6785 my ( $i, $o ) = split $tty, /,/; 6786 $o = $i unless defined $o; 6787 open( IN, "<$i" ) or die "Cannot open TTY '$i' for read: $!"; 6788 open( OUT, ">$o" ) or die "Cannot open TTY '$o' for write: $!"; 6789 $IN = \*IN; 6790 $OUT = \*OUT; 6791 _autoflush($OUT); 6792 } ## end if ($tty) 6793 6794 # We don't have a TTY - try to find one via Term::Rendezvous. 6795 else { 6796 require Term::Rendezvous; 6797 6798 # See if we have anything to pass to Term::Rendezvous. 6799 # Use $HOME/.perldbtty$$ if not. 6800 my $rv = $ENV{PERLDB_NOTTY} || "$ENV{HOME}/.perldbtty$$"; 6801 6802 # Rendezvous and get the filehandles. 6803 my $term_rv = Term::Rendezvous->new( $rv ); 6804 $IN = $term_rv->IN; 6805 $OUT = $term_rv->OUT; 6806 } ## end else [ if ($tty) 6807 } ## end if ($notty) 6808 6809 # We're a daughter debugger. Try to fork off another TTY. 6810 if ( $term_pid eq '-1' ) { # In a TTY with another debugger 6811 resetterm(2); 6812 } 6813 6814 # If we shouldn't use Term::ReadLine, don't. 6815 if ( !$rl ) { 6816 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT ); 6817 } 6818 6819 # We're using Term::ReadLine. Get all the attributes for this terminal. 6820 else { 6821 $term = Term::ReadLine->new( 'perldb', $IN, $OUT ); 6822 6823 $rl_attribs = $term->Attribs; 6824 $rl_attribs->{basic_word_break_characters} .= '-:+/*,[])}' 6825 if defined $rl_attribs->{basic_word_break_characters} 6826 and index( $rl_attribs->{basic_word_break_characters}, ":" ) == -1; 6827 $rl_attribs->{special_prefixes} = '$@&%'; 6828 $rl_attribs->{completer_word_break_characters} .= '$@&%'; 6829 $rl_attribs->{completion_function} = \&db_complete; 6830 } ## end else [ if (!$rl) 6831 6832 # Set up the LINEINFO filehandle. 6833 $LINEINFO = $OUT unless defined $LINEINFO; 6834 $lineinfo = $console unless defined $lineinfo; 6835 6836 $term->MinLine(2); 6837 6838 load_hist(); 6839 6840 if ( $term->Features->{setHistory} and "@hist" ne "?" ) { 6841 $term->SetHistory(@hist); 6842 } 6843 6844 # XXX Ornaments are turned on unconditionally, which is not 6845 # always a good thing. 6846 ornaments($ornaments) if defined $ornaments; 6847 $term_pid = $$; 6848} ## end sub setterm 6849 6850sub load_hist { 6851 $histfile //= option_val("HistFile", undef); 6852 return unless defined $histfile; 6853 open my $fh, "<", $histfile or return; 6854 local $/ = "\n"; 6855 @hist = (); 6856 while (<$fh>) { 6857 chomp; 6858 push @hist, $_; 6859 } 6860 close $fh; 6861} 6862 6863sub save_hist { 6864 return unless defined $histfile; 6865 eval { require File::Path } or return; 6866 eval { require File::Basename } or return; 6867 File::Path::mkpath(File::Basename::dirname($histfile)); 6868 open my $fh, ">", $histfile or die "Could not open '$histfile': $!"; 6869 $histsize //= option_val("HistSize",100); 6870 my @copy = grep { $_ ne '?' } @hist; 6871 my $start = scalar(@copy) > $histsize ? scalar(@copy)-$histsize : 0; 6872 for ($start .. $#copy) { 6873 print $fh "$copy[$_]\n"; 6874 } 6875 close $fh or die "Could not write '$histfile': $!"; 6876} 6877 6878=head1 GET_FORK_TTY EXAMPLE FUNCTIONS 6879 6880When the process being debugged forks, or the process invokes a command 6881via C<system()> which starts a new debugger, we need to be able to get a new 6882C<IN> and C<OUT> filehandle for the new debugger. Otherwise, the two processes 6883fight over the terminal, and you can never quite be sure who's going to get the 6884input you're typing. 6885 6886C<get_fork_TTY> is a glob-aliased function which calls the real function that 6887is tasked with doing all the necessary operating system mojo to get a new 6888TTY (and probably another window) and to direct the new debugger to read and 6889write there. 6890 6891The debugger provides C<get_fork_TTY> functions which work for TCP 6892socket servers, X11, OS/2, and Mac OS X. Other systems are not 6893supported. You are encouraged to write C<get_fork_TTY> functions which 6894work for I<your> platform and contribute them. 6895 6896=head3 C<socket_get_fork_TTY> 6897 6898=cut 6899 6900sub connect_remoteport { 6901 require IO::Socket; 6902 6903 my $socket = IO::Socket::INET->new( 6904 Timeout => '10', 6905 PeerAddr => $remoteport, 6906 Proto => 'tcp', 6907 ); 6908 if ( ! $socket ) { 6909 die "Unable to connect to remote host: $remoteport\n"; 6910 } 6911 return $socket; 6912} 6913 6914sub socket_get_fork_TTY { 6915 $tty = $LINEINFO = $IN = $OUT = connect_remoteport(); 6916 6917 # Do I need to worry about setting $term? 6918 6919 reset_IN_OUT( $IN, $OUT ); 6920 return ''; 6921} 6922 6923=head3 C<xterm_get_fork_TTY> 6924 6925This function provides the C<get_fork_TTY> function for X11. If a 6926program running under the debugger forks, a new <xterm> window is opened and 6927the subsidiary debugger is directed there. 6928 6929The C<open()> call is of particular note here. We have the new C<xterm> 6930we're spawning route file number 3 to STDOUT, and then execute the C<tty> 6931command (which prints the device name of the TTY we'll want to use for input 6932and output to STDOUT, then C<sleep> for a very long time, routing this output 6933to file number 3. This way we can simply read from the <XT> filehandle (which 6934is STDOUT from the I<commands> we ran) to get the TTY we want to use. 6935 6936Only works if C<xterm> is in your path and C<$ENV{DISPLAY}>, etc. are 6937properly set up. 6938 6939=cut 6940 6941sub xterm_get_fork_TTY { 6942 ( my $name = $0 ) =~ s,^.*[/\\],,s; 6943 open XT, 6944qq[3>&1 xterm -title "Daughter Perl debugger $pids $name" -e sh -c 'tty 1>&3;\ 6945 sleep 10000000' |]; 6946 6947 # Get the output from 'tty' and clean it up a little. 6948 my $tty = <XT>; 6949 chomp $tty; 6950 6951 $pidprompt = ''; # Shown anyway in titlebar 6952 6953 # We need $term defined or we can not switch to the newly created xterm 6954 if ($tty ne '' && !defined $term) { 6955 require Term::ReadLine; 6956 if ( !$rl ) { 6957 $term = Term::ReadLine::Stub->new( 'perldb', $IN, $OUT ); 6958 } 6959 else { 6960 $term = Term::ReadLine->new( 'perldb', $IN, $OUT ); 6961 } 6962 } 6963 # There's our new TTY. 6964 return $tty; 6965} ## end sub xterm_get_fork_TTY 6966 6967=head3 C<os2_get_fork_TTY> 6968 6969XXX It behooves an OS/2 expert to write the necessary documentation for this! 6970 6971=cut 6972 6973# This example function resets $IN, $OUT itself 6974my $c_pipe = 0; 6975sub os2_get_fork_TTY { # A simplification of the following (and works without): 6976 local $\ = ''; 6977 ( my $name = $0 ) =~ s,^.*[/\\],,s; 6978 my %opt = ( title => "Daughter Perl debugger $pids $name", 6979 ($rl ? (read_by_key => 1) : ()) ); 6980 require OS2::Process; 6981 my ($in, $out, $pid) = eval { OS2::Process::io_term(related => 0, %opt) } 6982 or return; 6983 $pidprompt = ''; # Shown anyway in titlebar 6984 reset_IN_OUT($in, $out); 6985 $tty = '*reset*'; 6986 return ''; # Indicate that reset_IN_OUT is called 6987} ## end sub os2_get_fork_TTY 6988 6989=head3 C<macosx_get_fork_TTY> 6990 6991The Mac OS X version uses AppleScript to tell Terminal.app to create 6992a new window. 6993 6994=cut 6995 6996# Notes about Terminal.app's AppleScript support, 6997# (aka things that might break in future OS versions). 6998# 6999# The "do script" command doesn't return a reference to the new window 7000# it creates, but since it appears frontmost and windows are enumerated 7001# front to back, we can use "first window" === "window 1". 7002# 7003# Since "do script" is implemented by supplying the argument (plus a 7004# return character) as terminal input, there's a potential race condition 7005# where the debugger could beat the shell to reading the command. 7006# To prevent this, we wait for the screen to clear before proceeding. 7007# 7008# 10.3 and 10.4: 7009# There's no direct accessor for the tty device name, so we fiddle 7010# with the window title options until it says what we want. 7011# 7012# 10.5: 7013# There _is_ a direct accessor for the tty device name, _and_ there's 7014# a new possible component of the window title (the name of the settings 7015# set). A separate version is needed. 7016 7017my @script_versions= 7018 7019 ([237, <<'__LEOPARD__'], 7020tell application "Terminal" 7021 do script "clear;exec sleep 100000" 7022 tell first tab of first window 7023 copy tty to thetty 7024 set custom title to "forked perl debugger" 7025 set title displays custom title to true 7026 repeat while (length of first paragraph of (get contents)) > 0 7027 delay 0.1 7028 end repeat 7029 end tell 7030end tell 7031thetty 7032__LEOPARD__ 7033 7034 [100, <<'__JAGUAR_TIGER__'], 7035tell application "Terminal" 7036 do script "clear;exec sleep 100000" 7037 tell first window 7038 set title displays shell path to false 7039 set title displays window size to false 7040 set title displays file name to false 7041 set title displays device name to true 7042 set title displays custom title to true 7043 set custom title to "" 7044 copy "/dev/" & name to thetty 7045 set custom title to "forked perl debugger" 7046 repeat while (length of first paragraph of (get contents)) > 0 7047 delay 0.1 7048 end repeat 7049 end tell 7050end tell 7051thetty 7052__JAGUAR_TIGER__ 7053 7054); 7055 7056sub macosx_get_fork_TTY 7057{ 7058 my($version,$script,$pipe,$tty); 7059 7060 return unless $version=$ENV{TERM_PROGRAM_VERSION}; 7061 foreach my $entry (@script_versions) { 7062 if ($version>=$entry->[0]) { 7063 $script=$entry->[1]; 7064 last; 7065 } 7066 } 7067 return unless defined($script); 7068 return unless open($pipe,'-|','/usr/bin/osascript','-e',$script); 7069 $tty=readline($pipe); 7070 close($pipe); 7071 return unless defined($tty) && $tty =~ m(^/dev/); 7072 chomp $tty; 7073 return $tty; 7074} 7075 7076=head2 C<create_IN_OUT($flags)> 7077 7078Create a new pair of filehandles, pointing to a new TTY. If impossible, 7079try to diagnose why. 7080 7081Flags are: 7082 7083=over 4 7084 7085=item * 1 - Don't know how to create a new TTY. 7086 7087=item * 2 - Debugger has forked, but we can't get a new TTY. 7088 7089=item * 4 - standard debugger startup is happening. 7090 7091=back 7092 7093=cut 7094 7095use vars qw($fork_TTY); 7096 7097sub create_IN_OUT { # Create a window with IN/OUT handles redirected there 7098 7099 # If we know how to get a new TTY, do it! $in will have 7100 # the TTY name if get_fork_TTY works. 7101 my $in = get_fork_TTY(@_) if defined &get_fork_TTY; 7102 7103 # It used to be that 7104 $in = $fork_TTY if defined $fork_TTY; # Backward compatibility 7105 7106 if ( not defined $in ) { 7107 my $why = shift; 7108 7109 # We don't know how. 7110 print_help(<<EOP) if $why == 1; 7111I<#########> Forked, but do not know how to create a new B<TTY>. I<#########> 7112EOP 7113 7114 # Forked debugger. 7115 print_help(<<EOP) if $why == 2; 7116I<#########> Daughter session, do not know how to change a B<TTY>. I<#########> 7117 This may be an asynchronous session, so the parent debugger may be active. 7118EOP 7119 7120 # Note that both debuggers are fighting over the same input. 7121 print_help(<<EOP) if $why != 4; 7122 Since two debuggers fight for the same TTY, input is severely entangled. 7123 7124EOP 7125 print_help(<<EOP); 7126 I know how to switch the output to a different window in xterms, OS/2 7127 consoles, and Mac OS X Terminal.app only. For a manual switch, put the name 7128 of the created I<TTY> in B<\$DB::fork_TTY>, or define a function 7129 B<DB::get_fork_TTY()> returning this. 7130 7131 On I<UNIX>-like systems one can get the name of a I<TTY> for the given window 7132 by typing B<tty>, and disconnect the I<shell> from I<TTY> by B<sleep 1000000>. 7133 7134EOP 7135 } ## end if (not defined $in) 7136 elsif ( $in ne '' ) { 7137 TTY($in); 7138 } 7139 else { 7140 $console = ''; # Indicate no need to open-from-the-console 7141 } 7142 undef $fork_TTY; 7143} ## end sub create_IN_OUT 7144 7145=head2 C<resetterm> 7146 7147Handles rejiggering the prompt when we've forked off a new debugger. 7148 7149If the new debugger happened because of a C<system()> that invoked a 7150program under the debugger, the arrow between the old pid and the new 7151in the prompt has I<two> dashes instead of one. 7152 7153We take the current list of pids and add this one to the end. If there 7154isn't any list yet, we make one up out of the initial pid associated with 7155the terminal and our new pid, sticking an arrow (either one-dashed or 7156two dashed) in between them. 7157 7158If C<CreateTTY> is off, or C<resetterm> was called with no arguments, 7159we don't try to create a new IN and OUT filehandle. Otherwise, we go ahead 7160and try to do that. 7161 7162=cut 7163 7164sub resetterm { # We forked, so we need a different TTY 7165 7166 # Needs to be passed to create_IN_OUT() as well. 7167 my $in = shift; 7168 7169 # resetterm(2): got in here because of a system() starting a debugger. 7170 # resetterm(1): just forked. 7171 my $systemed = $in > 1 ? '-' : ''; 7172 7173 # If there's already a list of pids, add this to the end. 7174 if ($pids) { 7175 $pids =~ s/\]/$systemed->$$]/; 7176 } 7177 7178 # No pid list. Time to make one. 7179 else { 7180 $pids = "[$term_pid->$$]"; 7181 } 7182 7183 # The prompt we're going to be using for this debugger. 7184 $pidprompt = $pids; 7185 7186 # We now 0wnz this terminal. 7187 $term_pid = $$; 7188 7189 # Just return if we're not supposed to try to create a new TTY. 7190 return unless $CreateTTY & $in; 7191 7192 # Try to create a new IN/OUT pair. 7193 create_IN_OUT($in); 7194} ## end sub resetterm 7195 7196=head2 C<readline> 7197 7198First, we handle stuff in the typeahead buffer. If there is any, we shift off 7199the next line, print a message saying we got it, add it to the terminal 7200history (if possible), and return it. 7201 7202If there's nothing in the typeahead buffer, check the command filehandle stack. 7203If there are any filehandles there, read from the last one, and return the line 7204if we got one. If not, we pop the filehandle off and close it, and try the 7205next one up the stack. 7206 7207If we've emptied the filehandle stack, we check to see if we've got a socket 7208open, and we read that and return it if we do. If we don't, we just call the 7209core C<readline()> and return its value. 7210 7211=cut 7212 7213sub readline { 7214 7215 # Localize to prevent it from being smashed in the program being debugged. 7216 local $.; 7217 7218 # If there are stacked filehandles to read from ... 7219 # (Handle it before the typeahead, because we may call source/etc. from 7220 # the typeahead.) 7221 while (@cmdfhs) { 7222 7223 # Read from the last one in the stack. 7224 my $line = CORE::readline( $cmdfhs[-1] ); 7225 7226 # If we got a line ... 7227 defined $line 7228 ? ( print $OUT ">> $line" and return $line ) # Echo and return 7229 : close pop @cmdfhs; # Pop and close 7230 } ## end while (@cmdfhs) 7231 7232 # Pull a line out of the typeahead if there's stuff there. 7233 if (@typeahead) { 7234 7235 # How many lines left. 7236 my $left = @typeahead; 7237 7238 # Get the next line. 7239 my $got = shift @typeahead; 7240 7241 # Print a message saying we got input from the typeahead. 7242 local $\ = ''; 7243 print $OUT "auto(-$left)", shift, $got, "\n"; 7244 7245 # Add it to the terminal history (if possible). 7246 $term->AddHistory($got) 7247 if length($got) > 1 7248 and defined $term->Features->{addHistory}; 7249 return $got; 7250 } ## end if (@typeahead) 7251 7252 # We really need to read some input. Turn off entry/exit trace and 7253 # return value printing. 7254 local $frame = 0; 7255 local $doret = -2; 7256 7257 # Nothing on the filehandle stack. Socket? 7258 if ( ref $OUT and UNIVERSAL::isa( $OUT, 'IO::Socket::INET' ) ) { 7259 7260 # Send anything we have to send. 7261 $OUT->write( join( '', @_ ) ); 7262 7263 # Receive anything there is to receive. 7264 my $stuff = ''; 7265 my $buf; 7266 my $first_time = 1; 7267 7268 while ($first_time or (length($buf) && ($stuff .= $buf) !~ /\n/)) 7269 { 7270 $first_time = 0; 7271 $IN->recv( $buf = '', 2048 ); # XXX "what's wrong with sysread?" 7272 # XXX Don't know. You tell me. 7273 } 7274 7275 # What we got. 7276 return $stuff; 7277 } ## end if (ref $OUT and UNIVERSAL::isa... 7278 7279 # No socket. Just read from the terminal. 7280 else { 7281 return $term->readline(@_); 7282 } 7283} ## end sub readline 7284 7285=head1 OPTIONS SUPPORT ROUTINES 7286 7287These routines handle listing and setting option values. 7288 7289=head2 C<dump_option> - list the current value of an option setting 7290 7291This routine uses C<option_val> to look up the value for an option. 7292It cleans up escaped single-quotes and then displays the option and 7293its value. 7294 7295=cut 7296 7297sub dump_option { 7298 my ( $opt, $val ) = @_; 7299 $val = option_val( $opt, 'N/A' ); 7300 $val =~ s/([\\\'])/\\$1/g; 7301 printf $OUT "%20s = '%s'\n", $opt, $val; 7302} ## end sub dump_option 7303 7304sub options2remember { 7305 foreach my $k (@RememberOnROptions) { 7306 $option{$k} = option_val( $k, 'N/A' ); 7307 } 7308 return %option; 7309} 7310 7311=head2 C<option_val> - find the current value of an option 7312 7313This can't just be a simple hash lookup because of the indirect way that 7314the option values are stored. Some are retrieved by calling a subroutine, 7315some are just variables. 7316 7317You must supply a default value to be used in case the option isn't set. 7318 7319=cut 7320 7321sub option_val { 7322 my ( $opt, $default ) = @_; 7323 my $val; 7324 7325 # Does this option exist, and is it a variable? 7326 # If so, retrieve the value via the value in %optionVars. 7327 if ( defined $optionVars{$opt} 7328 and defined ${ $optionVars{$opt} } ) 7329 { 7330 $val = ${ $optionVars{$opt} }; 7331 } 7332 7333 # Does this option exist, and it's a subroutine? 7334 # If so, call the subroutine via the ref in %optionAction 7335 # and capture the value. 7336 elsif ( defined $optionAction{$opt} 7337 and defined &{ $optionAction{$opt} } ) 7338 { 7339 $val = &{ $optionAction{$opt} }(); 7340 } 7341 7342 # If there's an action or variable for the supplied option, 7343 # but no value was set, use the default. 7344 elsif (defined $optionAction{$opt} and not defined $option{$opt} 7345 or defined $optionVars{$opt} and not defined ${ $optionVars{$opt} } ) 7346 { 7347 $val = $default; 7348 } 7349 7350 # Otherwise, do the simple hash lookup. 7351 else { 7352 $val = $option{$opt}; 7353 } 7354 7355 # If the value isn't defined, use the default. 7356 # Then return whatever the value is. 7357 $val = $default unless defined $val; 7358 $val; 7359} ## end sub option_val 7360 7361=head2 C<parse_options> 7362 7363Handles the parsing and execution of option setting/displaying commands. 7364 7365An option entered by itself is assumed to be I<set me to 1> (the default value) 7366if the option is a boolean one. If not, the user is prompted to enter a valid 7367value or to query the current value (via C<option? >). 7368 7369If C<option=value> is entered, we try to extract a quoted string from the 7370value (if it is quoted). If it's not, we just use the whole value as-is. 7371 7372We load any modules required to service this option, and then we set it: if 7373it just gets stuck in a variable, we do that; if there's a subroutine to 7374handle setting the option, we call that. 7375 7376Finally, if we're running in interactive mode, we display the effect of the 7377user's command back to the terminal, skipping this if we're setting things 7378during initialization. 7379 7380=cut 7381 7382sub parse_options { 7383 my ($s) = @_; 7384 local $\ = ''; 7385 7386 my $option; 7387 7388 # These options need a value. Don't allow them to be clobbered by accident. 7389 my %opt_needs_val = map { ( $_ => 1 ) } qw{ 7390 dumpDepth arrayDepth hashDepth LineInfo maxTraceLen ornaments windowSize 7391 pager quote ReadLine recallCommand RemotePort ShellBang TTY CommandSet 7392 }; 7393 7394 while (length($s)) { 7395 my $val_defaulted; 7396 7397 # Clean off excess leading whitespace. 7398 $s =~ s/^\s+// && next; 7399 7400 # Options are always all word characters, followed by a non-word 7401 # separator. 7402 if ($s !~ s/^(\w+)(\W?)//) { 7403 print {$OUT} "Invalid option '$s'\n"; 7404 last; 7405 } 7406 my ( $opt, $sep ) = ( $1, $2 ); 7407 7408 # Make sure that such an option exists. 7409 my $matches = ( grep { /^\Q$opt/ && ( $option = $_ ) } @options ) 7410 || ( grep { /^\Q$opt/i && ( $option = $_ ) } @options ); 7411 7412 unless ($matches) { 7413 print {$OUT} "Unknown option '$opt'\n"; 7414 next; 7415 } 7416 if ($matches > 1) { 7417 print {$OUT} "Ambiguous option '$opt'\n"; 7418 next; 7419 } 7420 my $val; 7421 7422 # '?' as separator means query, but must have whitespace after it. 7423 if ( "?" eq $sep ) { 7424 if ($s =~ /\A\S/) { 7425 print {$OUT} "Option query '$opt?' followed by non-space '$s'\n" ; 7426 7427 last; 7428 } 7429 7430 #&dump_option($opt); 7431 } ## end if ("?" eq $sep) 7432 7433 # Separator is whitespace (or just a carriage return). 7434 # They're going for a default, which we assume is 1. 7435 elsif ( $sep !~ /\S/ ) { 7436 $val_defaulted = 1; 7437 $val = "1"; # this is an evil default; make 'em set it! 7438 } 7439 7440 # Separator is =. Trying to set a value. 7441 elsif ( $sep eq "=" ) { 7442 7443 # If quoted, extract a quoted string. 7444 if ($s =~ s/ (["']) ( (?: \\. | (?! \1 ) [^\\] )* ) \1 //x) { 7445 my $quote = $1; 7446 ( $val = $2 ) =~ s/\\([$quote\\])/$1/g; 7447 } 7448 7449 # Not quoted. Use the whole thing. Warn about 'option='. 7450 else { 7451 $s =~ s/^(\S*)//; 7452 $val = $1; 7453 print OUT qq(Option better cleared using $opt=""\n) 7454 unless length $val; 7455 } ## end else [ if (s/ (["']) ( (?: \\. | (?! \1 ) [^\\] )* ) \1 //x) 7456 7457 } ## end elsif ($sep eq "=") 7458 7459 # "Quoted" with [], <>, or {}. 7460 else { #{ to "let some poor schmuck bounce on the % key in B<vi>." 7461 my ($end) = 7462 "\\" . substr( ")]>}$sep", index( "([<{", $sep ), 1 ); #} 7463 $s =~ s/^(([^\\$end]|\\[\\$end])*)$end($|\s+)// 7464 or print( $OUT "Unclosed option value '$opt$sep$_'\n" ), last; 7465 ( $val = $1 ) =~ s/\\([\\$end])/$1/g; 7466 } ## end else [ if ("?" eq $sep) 7467 7468 # Exclude non-booleans from getting set to 1 by default. 7469 if ( $opt_needs_val{$option} && $val_defaulted ) { 7470 my $cmd = ( $CommandSet eq '580' ) ? 'o' : 'O'; 7471 print {$OUT} 7472"Option '$opt' is non-boolean. Use '$cmd $option=VAL' to set, '$cmd $option?' to query\n"; 7473 next; 7474 } ## end if ($opt_needs_val{$option... 7475 7476 # Save the option value. 7477 $option{$option} = $val if defined $val; 7478 7479 # Load any module that this option requires. 7480 if ( defined($optionRequire{$option}) && defined($val) ) { 7481 eval qq{ 7482 local \$frame = 0; 7483 local \$doret = -2; 7484 require '$optionRequire{$option}'; 7485 1; 7486 } || die $@ # XXX: shouldn't happen 7487 } 7488 7489 # Set it. 7490 # Stick it in the proper variable if it goes in a variable. 7491 if (defined($optionVars{$option}) && defined($val)) { 7492 ${ $optionVars{$option} } = $val; 7493 } 7494 7495 # Call the appropriate sub if it gets set via sub. 7496 if (defined($optionAction{$option}) 7497 && defined (&{ $optionAction{$option} }) 7498 && defined ($val)) 7499 { 7500 &{ $optionAction{$option} }($val); 7501 } 7502 7503 # Not initialization - echo the value we set it to. 7504 dump_option($option) if ($OUT ne \*STDERR); 7505 } ## end while (length) 7506} ## end sub parse_options 7507 7508=head1 RESTART SUPPORT 7509 7510These routines are used to store (and restore) lists of items in environment 7511variables during a restart. 7512 7513=head2 set_list 7514 7515Set_list packages up items to be stored in a set of environment variables 7516(VAR_n, containing the number of items, and VAR_0, VAR_1, etc., containing 7517the values). Values outside the standard ASCII charset are stored by encoding 7518then as hexadecimal values. 7519 7520=cut 7521 7522sub set_list { 7523 my ( $stem, @list ) = @_; 7524 my $val; 7525 7526 # VAR_n: how many we have. Scalar assignment gets the number of items. 7527 $ENV{"${stem}_n"} = @list; 7528 7529 # Grab each item in the list, escape the backslashes, encode the non-ASCII 7530 # as hex, and then save in the appropriate VAR_0, VAR_1, etc. 7531 for my $i ( 0 .. $#list ) { 7532 $val = $list[$i]; 7533 $val =~ s/\\/\\\\/g; 7534 $val =~ s/([\0-\37\177\200-\377])/"\\0x" . unpack('H2',$1)/eg; 7535 $ENV{"${stem}_$i"} = $val; 7536 } ## end for $i (0 .. $#list) 7537} ## end sub set_list 7538 7539=head2 get_list 7540 7541Reverse the set_list operation: grab VAR_n to see how many we should be getting 7542back, and then pull VAR_0, VAR_1. etc. back out. 7543 7544=cut 7545 7546sub get_list { 7547 my $stem = shift; 7548 my @list; 7549 my $n = delete $ENV{"${stem}_n"}; 7550 my $val; 7551 for my $i ( 0 .. $n - 1 ) { 7552 $val = delete $ENV{"${stem}_$i"}; 7553 $val =~ s/\\((\\)|0x(..))/ $2 ? $2 : pack('H2', $3) /ge; 7554 push @list, $val; 7555 } 7556 @list; 7557} ## end sub get_list 7558 7559=head1 MISCELLANEOUS SIGNAL AND I/O MANAGEMENT 7560 7561=head2 catch() 7562 7563The C<catch()> subroutine is the essence of fast and low-impact. We simply 7564set an already-existing global scalar variable to a constant value. This 7565avoids allocating any memory possibly in the middle of something that will 7566get all confused if we do, particularly under I<unsafe signals>. 7567 7568=cut 7569 7570sub catch { 7571 $signal = 1; 7572 return; # Put nothing on the stack - malloc/free land! 7573} 7574 7575=head2 C<warn()> 7576 7577C<warn> emits a warning, by joining together its arguments and printing 7578them, with couple of fillips. 7579 7580If the composited message I<doesn't> end with a newline, we automatically 7581add C<$!> and a newline to the end of the message. The subroutine expects $OUT 7582to be set to the filehandle to be used to output warnings; it makes no 7583assumptions about what filehandles are available. 7584 7585=cut 7586 7587sub _db_warn { 7588 my ($msg) = join( "", @_ ); 7589 $msg .= ": $!\n" unless $msg =~ /\n$/; 7590 local $\ = ''; 7591 print $OUT $msg; 7592} ## end sub warn 7593 7594*warn = \&_db_warn; 7595 7596=head1 INITIALIZATION TTY SUPPORT 7597 7598=head2 C<reset_IN_OUT> 7599 7600This routine handles restoring the debugger's input and output filehandles 7601after we've tried and failed to move them elsewhere. In addition, it assigns 7602the debugger's output filehandle to $LINEINFO if it was already open there. 7603 7604=cut 7605 7606sub reset_IN_OUT { 7607 my $switch_li = $LINEINFO eq $OUT; 7608 7609 # If there's a term and it's able to get a new tty, try to get one. 7610 if ( $term and $term->Features->{newTTY} ) { 7611 ( $IN, $OUT ) = ( shift, shift ); 7612 $term->newTTY( $IN, $OUT ); 7613 } 7614 7615 # This term can't get a new tty now. Better luck later. 7616 elsif ($term) { 7617 _db_warn("Too late to set IN/OUT filehandles, enabled on next 'R'!\n"); 7618 } 7619 7620 # Set the filehndles up as they were. 7621 else { 7622 ( $IN, $OUT ) = ( shift, shift ); 7623 } 7624 7625 # Unbuffer the output filehandle. 7626 _autoflush($OUT); 7627 7628 # Point LINEINFO to the same output filehandle if it was there before. 7629 $LINEINFO = $OUT if $switch_li; 7630} ## end sub reset_IN_OUT 7631 7632=head1 OPTION SUPPORT ROUTINES 7633 7634The following routines are used to process some of the more complicated 7635debugger options. 7636 7637=head2 C<TTY> 7638 7639Sets the input and output filehandles to the specified files or pipes. 7640If the terminal supports switching, we go ahead and do it. If not, and 7641there's already a terminal in place, we save the information to take effect 7642on restart. 7643 7644If there's no terminal yet (for instance, during debugger initialization), 7645we go ahead and set C<$console> and C<$tty> to the file indicated. 7646 7647=cut 7648 7649sub TTY { 7650 7651 if ( @_ and $term and $term->Features->{newTTY} ) { 7652 7653 # This terminal supports switching to a new TTY. 7654 # Can be a list of two files, or on string containing both names, 7655 # comma-separated. 7656 # XXX Should this perhaps be an assignment from @_? 7657 my ( $in, $out ) = shift; 7658 if ( $in =~ /,/ ) { 7659 7660 # Split list apart if supplied. 7661 ( $in, $out ) = split /,/, $in, 2; 7662 } 7663 else { 7664 7665 # Use the same file for both input and output. 7666 $out = $in; 7667 } 7668 7669 # Open file onto the debugger's filehandles, if you can. 7670 open IN, $in or die "cannot open '$in' for read: $!"; 7671 open OUT, ">$out" or die "cannot open '$out' for write: $!"; 7672 7673 # Swap to the new filehandles. 7674 reset_IN_OUT( \*IN, \*OUT ); 7675 7676 # Save the setting for later. 7677 return $tty = $in; 7678 } ## end if (@_ and $term and $term... 7679 7680 # Terminal doesn't support new TTY, or doesn't support readline. 7681 # Can't do it now, try restarting. 7682 if ($term and @_) { 7683 _db_warn("Too late to set TTY, enabled on next 'R'!\n"); 7684 } 7685 7686 # Useful if done through PERLDB_OPTS: 7687 $console = $tty = shift if @_; 7688 7689 # Return whatever the TTY is. 7690 $tty or $console; 7691} ## end sub TTY 7692 7693=head2 C<noTTY> 7694 7695Sets the C<$notty> global, controlling whether or not the debugger tries to 7696get a terminal to read from. If called after a terminal is already in place, 7697we save the value to use it if we're restarted. 7698 7699=cut 7700 7701sub noTTY { 7702 if ($term) { 7703 _db_warn("Too late to set noTTY, enabled on next 'R'!\n") if @_; 7704 } 7705 $notty = shift if @_; 7706 $notty; 7707} ## end sub noTTY 7708 7709=head2 C<ReadLine> 7710 7711Sets the C<$rl> option variable. If 0, we use C<Term::ReadLine::Stub> 7712(essentially, no C<readline> processing on this I<terminal>). Otherwise, we 7713use C<Term::ReadLine>. Can't be changed after a terminal's in place; we save 7714the value in case a restart is done so we can change it then. 7715 7716=cut 7717 7718sub ReadLine { 7719 if ($term) { 7720 _db_warn("Too late to set ReadLine, enabled on next 'R'!\n") if @_; 7721 } 7722 $rl = shift if @_; 7723 $rl; 7724} ## end sub ReadLine 7725 7726=head2 C<RemotePort> 7727 7728Sets the port that the debugger will try to connect to when starting up. 7729If the terminal's already been set up, we can't do it, but we remember the 7730setting in case the user does a restart. 7731 7732=cut 7733 7734sub RemotePort { 7735 if ($term) { 7736 _db_warn("Too late to set RemotePort, enabled on next 'R'!\n") if @_; 7737 } 7738 $remoteport = shift if @_; 7739 $remoteport; 7740} ## end sub RemotePort 7741 7742=head2 C<tkRunning> 7743 7744Checks with the terminal to see if C<Tk> is running, and returns true or 7745false. Returns false if the current terminal doesn't support C<readline>. 7746 7747=cut 7748 7749sub tkRunning { 7750 if ( ${ $term->Features }{tkRunning} ) { 7751 return $term->tkRunning(@_); 7752 } 7753 else { 7754 local $\ = ''; 7755 print $OUT "tkRunning not supported by current ReadLine package.\n"; 7756 0; 7757 } 7758} ## end sub tkRunning 7759 7760=head2 C<NonStop> 7761 7762Sets nonstop mode. If a terminal's already been set up, it's too late; the 7763debugger remembers the setting in case you restart, though. 7764 7765=cut 7766 7767sub NonStop { 7768 if ($term) { 7769 _db_warn("Too late to set up NonStop mode, enabled on next 'R'!\n") 7770 if @_; 7771 } 7772 $runnonstop = shift if @_; 7773 $runnonstop; 7774} ## end sub NonStop 7775 7776sub DollarCaretP { 7777 if ($term) { 7778 _db_warn("Some flag changes could not take effect until next 'R'!\n") 7779 if @_; 7780 } 7781 $^P = parse_DollarCaretP_flags(shift) if @_; 7782 expand_DollarCaretP_flags($^P); 7783} 7784 7785=head2 C<pager> 7786 7787Set up the C<$pager> variable. Adds a pipe to the front unless there's one 7788there already. 7789 7790=cut 7791 7792sub pager { 7793 if (@_) { 7794 $pager = shift; 7795 $pager = "|" . $pager unless $pager =~ /^(\+?\>|\|)/; 7796 } 7797 $pager; 7798} ## end sub pager 7799 7800=head2 C<shellBang> 7801 7802Sets the shell escape command, and generates a printable copy to be used 7803in the help. 7804 7805=cut 7806 7807sub shellBang { 7808 7809 # If we got an argument, meta-quote it, and add '\b' if it 7810 # ends in a word character. 7811 if (@_) { 7812 $sh = quotemeta shift; 7813 $sh .= "\\b" if $sh =~ /\w$/; 7814 } 7815 7816 # Generate the printable version for the help: 7817 $psh = $sh; # copy it 7818 $psh =~ s/\\b$//; # Take off trailing \b if any 7819 $psh =~ s/\\(.)/$1/g; # De-escape 7820 $psh; # return the printable version 7821} ## end sub shellBang 7822 7823=head2 C<ornaments> 7824 7825If the terminal has its own ornaments, fetch them. Otherwise accept whatever 7826was passed as the argument. (This means you can't override the terminal's 7827ornaments.) 7828 7829=cut 7830 7831sub ornaments { 7832 if ( defined $term ) { 7833 7834 # We don't want to show warning backtraces, but we do want die() ones. 7835 local $warnLevel = 0; 7836 local $dieLevel = 1; 7837 7838 # No ornaments if the terminal doesn't support them. 7839 if (not $term->Features->{ornaments}) { 7840 return ''; 7841 } 7842 7843 return (eval { $term->ornaments(@_) } || ''); 7844 } 7845 7846 # Use what was passed in if we can't determine it ourselves. 7847 else { 7848 $ornaments = shift; 7849 7850 return $ornaments; 7851 } 7852 7853} ## end sub ornaments 7854 7855=head2 C<recallCommand> 7856 7857Sets the recall command, and builds a printable version which will appear in 7858the help text. 7859 7860=cut 7861 7862sub recallCommand { 7863 7864 # If there is input, metaquote it. Add '\b' if it ends with a word 7865 # character. 7866 if (@_) { 7867 $rc = quotemeta shift; 7868 $rc .= "\\b" if $rc =~ /\w$/; 7869 } 7870 7871 # Build it into a printable version. 7872 $prc = $rc; # Copy it 7873 $prc =~ s/\\b$//; # Remove trailing \b 7874 $prc =~ s/\\(.)/$1/g; # Remove escapes 7875 return $prc; # Return the printable version 7876} ## end sub recallCommand 7877 7878=head2 C<LineInfo> - where the line number information goes 7879 7880Called with no arguments, returns the file or pipe that line info should go to. 7881 7882Called with an argument (a file or a pipe), it opens that onto the 7883C<LINEINFO> filehandle, unbuffers the filehandle, and then returns the 7884file or pipe again to the caller. 7885 7886=cut 7887 7888sub LineInfo { 7889 if (@_) { 7890 $lineinfo = shift; 7891 7892 # If this is a valid "thing to be opened for output", tack a 7893 # '>' onto the front. 7894 my $stream = ( $lineinfo =~ /^(\+?\>|\|)/ ) ? $lineinfo : ">$lineinfo"; 7895 7896 # If this is a pipe, the stream points to a slave editor. 7897 $slave_editor = ( $stream =~ /^\|/ ); 7898 7899 my $new_lineinfo_fh; 7900 # Open it up and unbuffer it. 7901 open ($new_lineinfo_fh , $stream ) 7902 or _db_warn("Cannot open '$stream' for write"); 7903 $LINEINFO = $new_lineinfo_fh; 7904 _autoflush($LINEINFO); 7905 } 7906 7907 return $lineinfo; 7908} ## end sub LineInfo 7909 7910=head1 COMMAND SUPPORT ROUTINES 7911 7912These subroutines provide functionality for various commands. 7913 7914=head2 C<list_modules> 7915 7916For the C<M> command: list modules loaded and their versions. 7917Essentially just runs through the keys in %INC, picks each package's 7918C<$VERSION> variable, gets the file name, and formats the information 7919for output. 7920 7921=cut 7922 7923sub list_modules { # versions 7924 my %version; 7925 my $file; 7926 7927 # keys are the "as-loaded" name, values are the fully-qualified path 7928 # to the file itself. 7929 for ( keys %INC ) { 7930 $file = $_; # get the module name 7931 s,\.p[lm]$,,i; # remove '.pl' or '.pm' 7932 s,/,::,g; # change '/' to '::' 7933 s/^perl5db$/DB/; # Special case: debugger 7934 # moves to package DB 7935 s/^Term::ReadLine::readline$/readline/; # simplify readline 7936 7937 # If the package has a $VERSION package global (as all good packages 7938 # should!) decode it and save as partial message. 7939 my $pkg_version = do { no strict 'refs'; ${ $_ . '::VERSION' } }; 7940 if ( defined $pkg_version ) { 7941 $version{$file} = "$pkg_version from "; 7942 } 7943 7944 # Finish up the message with the file the package came from. 7945 $version{$file} .= $INC{$file}; 7946 } ## end for (keys %INC) 7947 7948 # Hey, dumpit() formats a hash nicely, so why not use it? 7949 dumpit( $OUT, \%version ); 7950} ## end sub list_modules 7951 7952=head2 C<sethelp()> 7953 7954Sets up the monster string used to format and print the help. 7955 7956=head3 HELP MESSAGE FORMAT 7957 7958The help message is a peculiar format unto itself; it mixes C<pod> I<ornaments> 7959(C<< B<> >> C<< I<> >>) with tabs to come up with a format that's fairly 7960easy to parse and portable, but which still allows the help to be a little 7961nicer than just plain text. 7962 7963Essentially, you define the command name (usually marked up with C<< B<> >> 7964and C<< I<> >>), followed by a tab, and then the descriptive text, ending in a 7965newline. The descriptive text can also be marked up in the same way. If you 7966need to continue the descriptive text to another line, start that line with 7967just tabs and then enter the marked-up text. 7968 7969If you are modifying the help text, I<be careful>. The help-string parser is 7970not very sophisticated, and if you don't follow these rules it will mangle the 7971help beyond hope until you fix the string. 7972 7973=cut 7974 7975use vars qw($pre580_help); 7976use vars qw($pre580_summary); 7977 7978sub sethelp { 7979 7980 # XXX: make sure there are tabs between the command and explanation, 7981 # or print_help will screw up your formatting if you have 7982 # eeevil ornaments enabled. This is an insane mess. 7983 7984 $help = " 7985Help is currently only available for the new 5.8 command set. 7986No help is available for the old command set. 7987We assume you know what you're doing if you switch to it. 7988 7989B<T> Stack trace. 7990B<s> [I<expr>] Single step [in I<expr>]. 7991B<n> [I<expr>] Next, steps over subroutine calls [in I<expr>]. 7992<B<CR>> Repeat last B<n> or B<s> command. 7993B<r> Return from current subroutine. 7994B<c> [I<line>|I<sub>] Continue; optionally inserts a one-time-only breakpoint 7995 at the specified position. 7996B<l> I<min>B<+>I<incr> List I<incr>+1 lines starting at I<min>. 7997B<l> I<min>B<->I<max> List lines I<min> through I<max>. 7998B<l> I<line> List single I<line>. 7999B<l> I<subname> List first window of lines from subroutine. 8000B<l> I<\$var> List first window of lines from subroutine referenced by I<\$var>. 8001B<l> List next window of lines. 8002B<-> List previous window of lines. 8003B<v> [I<line>] View window around I<line>. 8004B<.> Return to the executed line. 8005B<f> I<filename> Switch to viewing I<filename>. File must be already loaded. 8006 I<filename> may be either the full name of the file, or a regular 8007 expression matching the full file name: 8008 B<f> I</home/me/foo.pl> and B<f> I<oo\\.> may access the same file. 8009 Evals (with saved bodies) are considered to be filenames: 8010 B<f> I<(eval 7)> and B<f> I<eval 7\\b> access the body of the 7th eval 8011 (in the order of execution). 8012B</>I<pattern>B</> Search forwards for I<pattern>; final B</> is optional. 8013B<?>I<pattern>B<?> Search backwards for I<pattern>; final B<?> is optional. 8014B<L> [I<a|b|w>] List actions and or breakpoints and or watch-expressions. 8015B<S> [[B<!>]I<pattern>] List subroutine names [not] matching I<pattern>. 8016B<t> [I<n>] Toggle trace mode (to max I<n> levels below current stack depth). 8017B<t> [I<n>] I<expr> Trace through execution of I<expr>. 8018B<b> Sets breakpoint on current line) 8019B<b> [I<line>] [I<condition>] 8020 Set breakpoint; I<line> defaults to the current execution line; 8021 I<condition> breaks if it evaluates to true, defaults to '1'. 8022B<b> I<subname> [I<condition>] 8023 Set breakpoint at first line of subroutine. 8024B<b> I<\$var> Set breakpoint at first line of subroutine referenced by I<\$var>. 8025B<b> B<load> I<filename> Set breakpoint on 'require'ing the given file. 8026B<b> B<postpone> I<subname> [I<condition>] 8027 Set breakpoint at first line of subroutine after 8028 it is compiled. 8029B<b> B<compile> I<subname> 8030 Stop after the subroutine is compiled. 8031B<B> [I<line>] Delete the breakpoint for I<line>. 8032B<B> I<*> Delete all breakpoints. 8033B<a> [I<line>] I<command> 8034 Set an action to be done before the I<line> is executed; 8035 I<line> defaults to the current execution line. 8036 Sequence is: check for breakpoint/watchpoint, print line 8037 if necessary, do action, prompt user if necessary, 8038 execute line. 8039B<a> Does nothing 8040B<A> [I<line>] Delete the action for I<line>. 8041B<A> I<*> Delete all actions. 8042B<w> I<expr> Add a global watch-expression. 8043B<w> Does nothing 8044B<W> I<expr> Delete a global watch-expression. 8045B<W> I<*> Delete all watch-expressions. 8046B<V> [I<pkg> [I<vars>]] List some (default all) variables in package (default current). 8047 Use B<~>I<pattern> and B<!>I<pattern> for positive and negative regexps. 8048B<X> [I<vars>] Same as \"B<V> I<currentpackage> [I<vars>]\". 8049B<x> I<expr> Evals expression in list context, dumps the result. 8050B<m> I<expr> Evals expression in list context, prints methods callable 8051 on the first element of the result. 8052B<m> I<class> Prints methods callable via the given class. 8053B<M> Show versions of loaded modules. 8054B<i> I<class> Prints nested parents of given class. 8055B<e> Display current thread id. 8056B<E> Display all thread ids the current one will be identified: <n>. 8057B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>. 8058 8059B<<> ? List Perl commands to run before each prompt. 8060B<<> I<expr> Define Perl command to run before each prompt. 8061B<<<> I<expr> Add to the list of Perl commands to run before each prompt. 8062B<< *> Delete the list of perl commands to run before each prompt. 8063B<>> ? List Perl commands to run after each prompt. 8064B<>> I<expr> Define Perl command to run after each prompt. 8065B<>>B<>> I<expr> Add to the list of Perl commands to run after each prompt. 8066B<>>B< *> Delete the list of Perl commands to run after each prompt. 8067B<{> I<db_command> Define debugger command to run before each prompt. 8068B<{> ? List debugger commands to run before each prompt. 8069B<{{> I<db_command> Add to the list of debugger commands to run before each prompt. 8070B<{ *> Delete the list of debugger commands to run before each prompt. 8071B<$prc> I<number> Redo a previous command (default previous command). 8072B<$prc> I<-number> Redo number'th-to-last command. 8073B<$prc> I<pattern> Redo last command that started with I<pattern>. 8074 See 'B<O> I<recallCommand>' too. 8075B<$psh$psh> I<cmd> Run cmd in a subprocess (reads from DB::IN, writes to DB::OUT)" 8076 . ( 8077 $rc eq $sh 8078 ? "" 8079 : " 8080B<$psh> [I<cmd>] Run I<cmd> in subshell (forces \"\$SHELL -c 'cmd'\")." 8081 ) . " 8082 See 'B<O> I<shellBang>' too. 8083B<source> I<file> Execute I<file> containing debugger commands (may nest). 8084B<save> I<file> Save current debugger session (actual history) to I<file>. 8085B<rerun> Rerun session to current position. 8086B<rerun> I<n> Rerun session to numbered command. 8087B<rerun> I<-n> Rerun session to number'th-to-last command. 8088B<H> I<-number> Display last number commands (default all). 8089B<H> I<*> Delete complete history. 8090B<p> I<expr> Same as \"I<print {DB::OUT} expr>\" in current package. 8091B<|>I<dbcmd> Run debugger command, piping DB::OUT to current pager. 8092B<||>I<dbcmd> Same as B<|>I<dbcmd> but DB::OUT is temporarily select()ed as well. 8093B<\=> [I<alias> I<value>] Define a command alias, or list current aliases. 8094I<command> Execute as a perl statement in current package. 8095B<R> Pure-man-restart of debugger, some of debugger state 8096 and command-line options may be lost. 8097 Currently the following settings are preserved: 8098 history, breakpoints and actions, debugger B<O>ptions 8099 and the following command-line options: I<-w>, I<-I>, I<-e>. 8100 8101B<o> [I<opt>] ... Set boolean option to true 8102B<o> [I<opt>B<?>] Query options 8103B<o> [I<opt>B<=>I<val>] [I<opt>=B<\">I<val>B<\">] ... 8104 Set options. Use quotes if spaces in value. 8105 I<recallCommand>, I<ShellBang> chars used to recall command or spawn shell; 8106 I<pager> program for output of \"|cmd\"; 8107 I<tkRunning> run Tk while prompting (with ReadLine); 8108 I<signalLevel> I<warnLevel> I<dieLevel> level of verbosity; 8109 I<inhibit_exit> Allows stepping off the end of the script. 8110 I<ImmediateStop> Debugger should stop as early as possible. 8111 I<RemotePort> Remote hostname:port for remote debugging 8112 The following options affect what happens with B<V>, B<X>, and B<x> commands: 8113 I<arrayDepth>, I<hashDepth> print only first N elements ('' for all); 8114 I<compactDump>, I<veryCompact> change style of array and hash dump; 8115 I<globPrint> whether to print contents of globs; 8116 I<DumpDBFiles> dump arrays holding debugged files; 8117 I<DumpPackages> dump symbol tables of packages; 8118 I<DumpReused> dump contents of \"reused\" addresses; 8119 I<quote>, I<HighBit>, I<undefPrint> change style of string dump; 8120 I<bareStringify> Do not print the overload-stringified value; 8121 Other options include: 8122 I<PrintRet> affects printing of return value after B<r> command, 8123 I<frame> affects printing messages on subroutine entry/exit. 8124 I<AutoTrace> affects printing messages on possible breaking points. 8125 I<maxTraceLen> gives max length of evals/args listed in stack trace. 8126 I<ornaments> affects screen appearance of the command line. 8127 I<CreateTTY> bits control attempts to create a new TTY on events: 8128 1: on fork() 2: debugger is started inside debugger 8129 4: on startup 8130 During startup options are initialized from \$ENV{PERLDB_OPTS}. 8131 You can put additional initialization options I<TTY>, I<noTTY>, 8132 I<ReadLine>, I<NonStop>, and I<RemotePort> there (or use 8133 B<R> after you set them). 8134 8135B<q> or B<^D> Quit. Set B<\$DB::finished = 0> to debug global destruction. 8136B<h> Summary of debugger commands. 8137B<h> [I<db_command>] Get help [on a specific debugger command], enter B<|h> to page. 8138B<h h> Long help for debugger commands 8139B<$doccmd> I<manpage> Runs the external doc viewer B<$doccmd> command on the 8140 named Perl I<manpage>, or on B<$doccmd> itself if omitted. 8141 Set B<\$DB::doccmd> to change viewer. 8142 8143Type '|h h' for a paged display if this was too hard to read. 8144 8145"; # Fix balance of vi % matching: }}}} 8146 8147 # note: tabs in the following section are not-so-helpful 8148 $summary = <<"END_SUM"; 8149I<List/search source lines:> I<Control script execution:> 8150 B<l> [I<ln>|I<sub>] List source code B<T> Stack trace 8151 B<-> or B<.> List previous/current line B<s> [I<expr>] Single step [in expr] 8152 B<v> [I<line>] View around line B<n> [I<expr>] Next, steps over subs 8153 B<f> I<filename> View source in file <B<CR>/B<Enter>> Repeat last B<n> or B<s> 8154 B</>I<pattern>B</> B<?>I<patt>B<?> Search forw/backw B<r> Return from subroutine 8155 B<M> Show module versions B<c> [I<ln>|I<sub>] Continue until position 8156I<Debugger controls:> B<L> List break/watch/actions 8157 B<o> [...] Set debugger options B<t> [I<n>] [I<expr>] Toggle trace [max depth] ][trace expr] 8158 B<<>[B<<>]|B<{>[B<{>]|B<>>[B<>>] [I<cmd>] Do pre/post-prompt B<b> [I<ln>|I<event>|I<sub>] [I<cnd>] Set breakpoint 8159 B<$prc> [I<N>|I<pat>] Redo a previous command B<B> I<ln|*> Delete a/all breakpoints 8160 B<H> [I<-num>] Display last num commands B<a> [I<ln>] I<cmd> Do cmd before line 8161 B<=> [I<a> I<val>] Define/list an alias B<A> I<ln|*> Delete a/all actions 8162 B<h> [I<db_cmd>] Get help on command B<w> I<expr> Add a watch expression 8163 B<h h> Complete help page B<W> I<expr|*> Delete a/all watch exprs 8164 B<|>[B<|>]I<db_cmd> Send output to pager B<$psh>\[B<$psh>\] I<syscmd> Run cmd in a subprocess 8165 B<q> or B<^D> Quit B<R> Attempt a restart 8166I<Data Examination:> B<expr> Execute perl code, also see: B<s>,B<n>,B<t> I<expr> 8167 B<x>|B<m> I<expr> Evals expr in list context, dumps the result or lists methods. 8168 B<p> I<expr> Print expression (uses script's current package). 8169 B<S> [[B<!>]I<pat>] List subroutine names [not] matching pattern 8170 B<V> [I<Pk> [I<Vars>]] List Variables in Package. Vars can be ~pattern or !pattern. 8171 B<X> [I<Vars>] Same as \"B<V> I<current_package> [I<Vars>]\". B<i> I<class> inheritance tree. 8172 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>. 8173 B<e> Display thread id B<E> Display all thread ids. 8174For more help, type B<h> I<cmd_letter>, or run B<$doccmd perldebug> for all docs. 8175END_SUM 8176 8177 # ')}}; # Fix balance of vi % matching 8178 8179 # and this is really numb... 8180 $pre580_help = " 8181B<T> Stack trace. 8182B<s> [I<expr>] Single step [in I<expr>]. 8183B<n> [I<expr>] Next, steps over subroutine calls [in I<expr>]. 8184B<CR>> Repeat last B<n> or B<s> command. 8185B<r> Return from current subroutine. 8186B<c> [I<line>|I<sub>] Continue; optionally inserts a one-time-only breakpoint 8187 at the specified position. 8188B<l> I<min>B<+>I<incr> List I<incr>+1 lines starting at I<min>. 8189B<l> I<min>B<->I<max> List lines I<min> through I<max>. 8190B<l> I<line> List single I<line>. 8191B<l> I<subname> List first window of lines from subroutine. 8192B<l> I<\$var> List first window of lines from subroutine referenced by I<\$var>. 8193B<l> List next window of lines. 8194B<-> List previous window of lines. 8195B<w> [I<line>] List window around I<line>. 8196B<.> Return to the executed line. 8197B<f> I<filename> Switch to viewing I<filename>. File must be already loaded. 8198 I<filename> may be either the full name of the file, or a regular 8199 expression matching the full file name: 8200 B<f> I</home/me/foo.pl> and B<f> I<oo\\.> may access the same file. 8201 Evals (with saved bodies) are considered to be filenames: 8202 B<f> I<(eval 7)> and B<f> I<eval 7\\b> access the body of the 7th eval 8203 (in the order of execution). 8204B</>I<pattern>B</> Search forwards for I<pattern>; final B</> is optional. 8205B<?>I<pattern>B<?> Search backwards for I<pattern>; final B<?> is optional. 8206B<L> List all breakpoints and actions. 8207B<S> [[B<!>]I<pattern>] List subroutine names [not] matching I<pattern>. 8208B<t> [I<n>] Toggle trace mode (to max I<n> levels below current stack depth) . 8209B<t> [I<n>] I<expr> Trace through execution of I<expr>. 8210B<b> [I<line>] [I<condition>] 8211 Set breakpoint; I<line> defaults to the current execution line; 8212 I<condition> breaks if it evaluates to true, defaults to '1'. 8213B<b> I<subname> [I<condition>] 8214 Set breakpoint at first line of subroutine. 8215B<b> I<\$var> Set breakpoint at first line of subroutine referenced by I<\$var>. 8216B<b> B<load> I<filename> Set breakpoint on 'require'ing the given file. 8217B<b> B<postpone> I<subname> [I<condition>] 8218 Set breakpoint at first line of subroutine after 8219 it is compiled. 8220B<b> B<compile> I<subname> 8221 Stop after the subroutine is compiled. 8222B<d> [I<line>] Delete the breakpoint for I<line>. 8223B<D> Delete all breakpoints. 8224B<a> [I<line>] I<command> 8225 Set an action to be done before the I<line> is executed; 8226 I<line> defaults to the current execution line. 8227 Sequence is: check for breakpoint/watchpoint, print line 8228 if necessary, do action, prompt user if necessary, 8229 execute line. 8230B<a> [I<line>] Delete the action for I<line>. 8231B<A> Delete all actions. 8232B<W> I<expr> Add a global watch-expression. 8233B<W> Delete all watch-expressions. 8234B<V> [I<pkg> [I<vars>]] List some (default all) variables in package (default current). 8235 Use B<~>I<pattern> and B<!>I<pattern> for positive and negative regexps. 8236B<X> [I<vars>] Same as \"B<V> I<currentpackage> [I<vars>]\". 8237B<x> I<expr> Evals expression in list context, dumps the result. 8238B<m> I<expr> Evals expression in list context, prints methods callable 8239 on the first element of the result. 8240B<m> I<class> Prints methods callable via the given class. 8241 8242B<<> ? List Perl commands to run before each prompt. 8243B<<> I<expr> Define Perl command to run before each prompt. 8244B<<<> I<expr> Add to the list of Perl commands to run before each prompt. 8245B<>> ? List Perl commands to run after each prompt. 8246B<>> I<expr> Define Perl command to run after each prompt. 8247B<>>B<>> I<expr> Add to the list of Perl commands to run after each prompt. 8248B<{> I<db_command> Define debugger command to run before each prompt. 8249B<{> ? List debugger commands to run before each prompt. 8250B<{{> I<db_command> Add to the list of debugger commands to run before each prompt. 8251B<$prc> I<number> Redo a previous command (default previous command). 8252B<$prc> I<-number> Redo number'th-to-last command. 8253B<$prc> I<pattern> Redo last command that started with I<pattern>. 8254 See 'B<O> I<recallCommand>' too. 8255B<$psh$psh> I<cmd> Run cmd in a subprocess (reads from DB::IN, writes to DB::OUT)" 8256 . ( 8257 $rc eq $sh 8258 ? "" 8259 : " 8260B<$psh> [I<cmd>] Run I<cmd> in subshell (forces \"\$SHELL -c 'cmd'\")." 8261 ) . " 8262 See 'B<O> I<shellBang>' too. 8263B<source> I<file> Execute I<file> containing debugger commands (may nest). 8264B<H> I<-number> Display last number commands (default all). 8265B<p> I<expr> Same as \"I<print {DB::OUT} expr>\" in current package. 8266B<|>I<dbcmd> Run debugger command, piping DB::OUT to current pager. 8267B<||>I<dbcmd> Same as B<|>I<dbcmd> but DB::OUT is temporarilly select()ed as well. 8268B<\=> [I<alias> I<value>] Define a command alias, or list current aliases. 8269I<command> Execute as a perl statement in current package. 8270B<v> Show versions of loaded modules. 8271B<R> Pure-man-restart of debugger, some of debugger state 8272 and command-line options may be lost. 8273 Currently the following settings are preserved: 8274 history, breakpoints and actions, debugger B<O>ptions 8275 and the following command-line options: I<-w>, I<-I>, I<-e>. 8276 8277B<O> [I<opt>] ... Set boolean option to true 8278B<O> [I<opt>B<?>] Query options 8279B<O> [I<opt>B<=>I<val>] [I<opt>=B<\">I<val>B<\">] ... 8280 Set options. Use quotes if spaces in value. 8281 I<recallCommand>, I<ShellBang> chars used to recall command or spawn shell; 8282 I<pager> program for output of \"|cmd\"; 8283 I<tkRunning> run Tk while prompting (with ReadLine); 8284 I<signalLevel> I<warnLevel> I<dieLevel> level of verbosity; 8285 I<inhibit_exit> Allows stepping off the end of the script. 8286 I<ImmediateStop> Debugger should stop as early as possible. 8287 I<RemotePort> Remote hostname:port for remote debugging 8288 The following options affect what happens with B<V>, B<X>, and B<x> commands: 8289 I<arrayDepth>, I<hashDepth> print only first N elements ('' for all); 8290 I<compactDump>, I<veryCompact> change style of array and hash dump; 8291 I<globPrint> whether to print contents of globs; 8292 I<DumpDBFiles> dump arrays holding debugged files; 8293 I<DumpPackages> dump symbol tables of packages; 8294 I<DumpReused> dump contents of \"reused\" addresses; 8295 I<quote>, I<HighBit>, I<undefPrint> change style of string dump; 8296 I<bareStringify> Do not print the overload-stringified value; 8297 Other options include: 8298 I<PrintRet> affects printing of return value after B<r> command, 8299 I<frame> affects printing messages on subroutine entry/exit. 8300 I<AutoTrace> affects printing messages on possible breaking points. 8301 I<maxTraceLen> gives max length of evals/args listed in stack trace. 8302 I<ornaments> affects screen appearance of the command line. 8303 I<CreateTTY> bits control attempts to create a new TTY on events: 8304 1: on fork() 2: debugger is started inside debugger 8305 4: on startup 8306 During startup options are initialized from \$ENV{PERLDB_OPTS}. 8307 You can put additional initialization options I<TTY>, I<noTTY>, 8308 I<ReadLine>, I<NonStop>, and I<RemotePort> there (or use 8309 B<R> after you set them). 8310 8311B<q> or B<^D> Quit. Set B<\$DB::finished = 0> to debug global destruction. 8312B<h> [I<db_command>] Get help [on a specific debugger command], enter B<|h> to page. 8313B<h h> Summary of debugger commands. 8314B<$doccmd> I<manpage> Runs the external doc viewer B<$doccmd> command on the 8315 named Perl I<manpage>, or on B<$doccmd> itself if omitted. 8316 Set B<\$DB::doccmd> to change viewer. 8317 8318Type '|h' for a paged display if this was too hard to read. 8319 8320"; # Fix balance of vi % matching: }}}} 8321 8322 # note: tabs in the following section are not-so-helpful 8323 $pre580_summary = <<"END_SUM"; 8324I<List/search source lines:> I<Control script execution:> 8325 B<l> [I<ln>|I<sub>] List source code B<T> Stack trace 8326 B<-> or B<.> List previous/current line B<s> [I<expr>] Single step [in expr] 8327 B<w> [I<line>] List around line B<n> [I<expr>] Next, steps over subs 8328 B<f> I<filename> View source in file <B<CR>/B<Enter>> Repeat last B<n> or B<s> 8329 B</>I<pattern>B</> B<?>I<patt>B<?> Search forw/backw B<r> Return from subroutine 8330 B<v> Show versions of modules B<c> [I<ln>|I<sub>] Continue until position 8331I<Debugger controls:> B<L> List break/watch/actions 8332 B<O> [...] Set debugger options B<t> [I<expr>] Toggle trace [trace expr] 8333 B<<>[B<<>]|B<{>[B<{>]|B<>>[B<>>] [I<cmd>] Do pre/post-prompt B<b> [I<ln>|I<event>|I<sub>] [I<cnd>] Set breakpoint 8334 B<$prc> [I<N>|I<pat>] Redo a previous command B<d> [I<ln>] or B<D> Delete a/all breakpoints 8335 B<H> [I<-num>] Display last num commands B<a> [I<ln>] I<cmd> Do cmd before line 8336 B<=> [I<a> I<val>] Define/list an alias B<W> I<expr> Add a watch expression 8337 B<h> [I<db_cmd>] Get help on command B<A> or B<W> Delete all actions/watch 8338 B<|>[B<|>]I<db_cmd> Send output to pager B<$psh>\[B<$psh>\] I<syscmd> Run cmd in a subprocess 8339 B<q> or B<^D> Quit B<R> Attempt a restart 8340I<Data Examination:> B<expr> Execute perl code, also see: B<s>,B<n>,B<t> I<expr> 8341 B<x>|B<m> I<expr> Evals expr in list context, dumps the result or lists methods. 8342 B<p> I<expr> Print expression (uses script's current package). 8343 B<S> [[B<!>]I<pat>] List subroutine names [not] matching pattern 8344 B<V> [I<Pk> [I<Vars>]] List Variables in Package. Vars can be ~pattern or !pattern. 8345 B<X> [I<Vars>] Same as \"B<V> I<current_package> [I<Vars>]\". 8346 B<y> [I<n> [I<Vars>]] List lexicals in higher scope <n>. Vars same as B<V>. 8347For more help, type B<h> I<cmd_letter>, or run B<$doccmd perldebug> for all docs. 8348END_SUM 8349 8350 # ')}}; # Fix balance of vi % matching 8351 8352} ## end sub sethelp 8353 8354=head2 C<print_help()> 8355 8356Most of what C<print_help> does is just text formatting. It finds the 8357C<B> and C<I> ornaments, cleans them off, and substitutes the proper 8358terminal control characters to simulate them (courtesy of 8359C<Term::ReadLine::TermCap>). 8360 8361=cut 8362 8363sub print_help { 8364 my $help_str = shift; 8365 8366 # Restore proper alignment destroyed by eeevil I<> and B<> 8367 # ornaments: A pox on both their houses! 8368 # 8369 # A help command will have everything up to and including 8370 # the first tab sequence padded into a field 16 (or if indented 20) 8371 # wide. If it's wider than that, an extra space will be added. 8372 $help_str =~ s{ 8373 ^ # only matters at start of line 8374 ( \040{4} | \t )* # some subcommands are indented 8375 ( < ? # so <CR> works 8376 [BI] < [^\t\n] + ) # find an eeevil ornament 8377 ( \t+ ) # original separation, discarded 8378 ( .* ) # this will now start (no earlier) than 8379 # column 16 8380 } { 8381 my($leadwhite, $command, $midwhite, $text) = ($1, $2, $3, $4); 8382 my $clean = $command; 8383 $clean =~ s/[BI]<([^>]*)>/$1/g; 8384 8385 # replace with this whole string: 8386 ($leadwhite ? " " x 4 : "") 8387 . $command 8388 . ((" " x (16 + ($leadwhite ? 4 : 0) - length($clean))) || " ") 8389 . $text; 8390 8391 }mgex; 8392 8393 $help_str =~ s{ # handle bold ornaments 8394 B < ( [^>] + | > ) > 8395 } { 8396 $Term::ReadLine::TermCap::rl_term_set[2] 8397 . $1 8398 . $Term::ReadLine::TermCap::rl_term_set[3] 8399 }gex; 8400 8401 $help_str =~ s{ # handle italic ornaments 8402 I < ( [^>] + | > ) > 8403 } { 8404 $Term::ReadLine::TermCap::rl_term_set[0] 8405 . $1 8406 . $Term::ReadLine::TermCap::rl_term_set[1] 8407 }gex; 8408 8409 local $\ = ''; 8410 print {$OUT} $help_str; 8411 8412 return; 8413} ## end sub print_help 8414 8415=head2 C<fix_less> 8416 8417This routine does a lot of gyrations to be sure that the pager is C<less>. 8418It checks for C<less> masquerading as C<more> and records the result in 8419C<$fixed_less> so we don't have to go through doing the stats again. 8420 8421=cut 8422 8423use vars qw($fixed_less); 8424 8425sub _calc_is_less { 8426 if ($pager =~ /\bless\b/) 8427 { 8428 return 1; 8429 } 8430 elsif ($pager =~ /\bmore\b/) 8431 { 8432 # Nope, set to more. See what's out there. 8433 my @st_more = stat('/usr/bin/more'); 8434 my @st_less = stat('/usr/bin/less'); 8435 8436 # is it really less, pretending to be more? 8437 return ( 8438 @st_more 8439 && @st_less 8440 && $st_more[0] == $st_less[0] 8441 && $st_more[1] == $st_less[1] 8442 ); 8443 } 8444 else { 8445 return; 8446 } 8447} 8448 8449sub fix_less { 8450 8451 # We already know if this is set. 8452 return if $fixed_less; 8453 8454 # changes environment! 8455 # 'r' added so we don't do (slow) stats again. 8456 $fixed_less = 1 if _calc_is_less(); 8457 8458 return; 8459} ## end sub fix_less 8460 8461=head1 DIE AND WARN MANAGEMENT 8462 8463=head2 C<diesignal> 8464 8465C<diesignal> is a just-drop-dead C<die> handler. It's most useful when trying 8466to debug a debugger problem. 8467 8468It does its best to report the error that occurred, and then forces the 8469program, debugger, and everything to die. 8470 8471=cut 8472 8473sub diesignal { 8474 8475 # No entry/exit messages. 8476 local $frame = 0; 8477 8478 # No return value prints. 8479 local $doret = -2; 8480 8481 # set the abort signal handling to the default (just terminate). 8482 $SIG{'ABRT'} = 'DEFAULT'; 8483 8484 # If we enter the signal handler recursively, kill myself with an 8485 # abort signal (so we just terminate). 8486 kill 'ABRT', $$ if $panic++; 8487 8488 # If we can show detailed info, do so. 8489 if ( defined &Carp::longmess ) { 8490 8491 # Don't recursively enter the warn handler, since we're carping. 8492 local $SIG{__WARN__} = ''; 8493 8494 # Skip two levels before reporting traceback: we're skipping 8495 # mydie and confess. 8496 local $Carp::CarpLevel = 2; # mydie + confess 8497 8498 # Tell us all about it. 8499 _db_warn( Carp::longmess("Signal @_") ); 8500 } 8501 8502 # No Carp. Tell us about the signal as best we can. 8503 else { 8504 local $\ = ''; 8505 print $DB::OUT "Got signal @_\n"; 8506 } 8507 8508 # Drop dead. 8509 kill 'ABRT', $$; 8510} ## end sub diesignal 8511 8512=head2 C<dbwarn> 8513 8514The debugger's own default C<$SIG{__WARN__}> handler. We load C<Carp> to 8515be able to get a stack trace, and output the warning message vi C<DB::dbwarn()>. 8516 8517=cut 8518 8519sub dbwarn { 8520 8521 # No entry/exit trace. 8522 local $frame = 0; 8523 8524 # No return value printing. 8525 local $doret = -2; 8526 8527 # Turn off warn and die handling to prevent recursive entries to this 8528 # routine. 8529 local $SIG{__WARN__} = ''; 8530 local $SIG{__DIE__} = ''; 8531 8532 # Load Carp if we can. If $^S is false (current thing being compiled isn't 8533 # done yet), we may not be able to do a require. 8534 eval { require Carp } 8535 if defined $^S; # If error/warning during compilation, 8536 # require may be broken. 8537 8538 # Use the core warn() unless Carp loaded OK. 8539 CORE::warn( @_, 8540 "\nCannot print stack trace, load with -MCarp option to see stack" ), 8541 return 8542 unless defined &Carp::longmess; 8543 8544 # Save the current values of $single and $trace, and then turn them off. 8545 my ( $mysingle, $mytrace ) = ( $single, $trace ); 8546 $single = 0; 8547 $trace = 0; 8548 8549 # We can call Carp::longmess without its being "debugged" (which we 8550 # don't want - we just want to use it!). Capture this for later. 8551 my $mess = Carp::longmess(@_); 8552 8553 # Restore $single and $trace to their original values. 8554 ( $single, $trace ) = ( $mysingle, $mytrace ); 8555 8556 # Use the debugger's own special way of printing warnings to print 8557 # the stack trace message. 8558 _db_warn($mess); 8559} ## end sub dbwarn 8560 8561=head2 C<dbdie> 8562 8563The debugger's own C<$SIG{__DIE__}> handler. Handles providing a stack trace 8564by loading C<Carp> and calling C<Carp::longmess()> to get it. We turn off 8565single stepping and tracing during the call to C<Carp::longmess> to avoid 8566debugging it - we just want to use it. 8567 8568If C<dieLevel> is zero, we let the program being debugged handle the 8569exceptions. If it's 1, you get backtraces for any exception. If it's 2, 8570the debugger takes over all exception handling, printing a backtrace and 8571displaying the exception via its C<dbwarn()> routine. 8572 8573=cut 8574 8575sub dbdie { 8576 local $frame = 0; 8577 local $doret = -2; 8578 local $SIG{__DIE__} = ''; 8579 local $SIG{__WARN__} = ''; 8580 if ( $dieLevel > 2 ) { 8581 local $SIG{__WARN__} = \&dbwarn; 8582 _db_warn(@_); # Yell no matter what 8583 return; 8584 } 8585 if ( $dieLevel < 2 ) { 8586 die @_ if $^S; # in eval propagate 8587 } 8588 8589 # The code used to check $^S to see if compilation of the current thing 8590 # hadn't finished. We don't do it anymore, figuring eval is pretty stable. 8591 eval { require Carp }; 8592 8593 die( @_, 8594 "\nCannot print stack trace, load with -MCarp option to see stack" ) 8595 unless defined &Carp::longmess; 8596 8597 # We do not want to debug this chunk (automatic disabling works 8598 # inside DB::DB, but not in Carp). Save $single and $trace, turn them off, 8599 # get the stack trace from Carp::longmess (if possible), restore $signal 8600 # and $trace, and then die with the stack trace. 8601 my ( $mysingle, $mytrace ) = ( $single, $trace ); 8602 $single = 0; 8603 $trace = 0; 8604 my $mess = "@_"; 8605 { 8606 8607 package Carp; # Do not include us in the list 8608 eval { $mess = Carp::longmess(@_); }; 8609 } 8610 ( $single, $trace ) = ( $mysingle, $mytrace ); 8611 die $mess; 8612} ## end sub dbdie 8613 8614=head2 C<warnlevel()> 8615 8616Set the C<$DB::warnLevel> variable that stores the value of the 8617C<warnLevel> option. Calling C<warnLevel()> with a positive value 8618results in the debugger taking over all warning handlers. Setting 8619C<warnLevel> to zero leaves any warning handlers set up by the program 8620being debugged in place. 8621 8622=cut 8623 8624sub warnLevel { 8625 if (@_) { 8626 my $prevwarn = $SIG{__WARN__} unless $warnLevel; 8627 $warnLevel = shift; 8628 if ($warnLevel) { 8629 $SIG{__WARN__} = \&DB::dbwarn; 8630 } 8631 elsif ($prevwarn) { 8632 $SIG{__WARN__} = $prevwarn; 8633 } else { 8634 undef $SIG{__WARN__}; 8635 } 8636 } ## end if (@_) 8637 $warnLevel; 8638} ## end sub warnLevel 8639 8640=head2 C<dielevel> 8641 8642Similar to C<warnLevel>. Non-zero values for C<dieLevel> result in the 8643C<DB::dbdie()> function overriding any other C<die()> handler. Setting it to 8644zero lets you use your own C<die()> handler. 8645 8646=cut 8647 8648sub dieLevel { 8649 local $\ = ''; 8650 if (@_) { 8651 my $prevdie = $SIG{__DIE__} unless $dieLevel; 8652 $dieLevel = shift; 8653 if ($dieLevel) { 8654 8655 # Always set it to dbdie() for non-zero values. 8656 $SIG{__DIE__} = \&DB::dbdie; # if $dieLevel < 2; 8657 8658 # No longer exists, so don't try to use it. 8659 #$SIG{__DIE__} = \&DB::diehard if $dieLevel >= 2; 8660 8661 # If we've finished initialization, mention that stack dumps 8662 # are enabled, If dieLevel is 1, we won't stack dump if we die 8663 # in an eval(). 8664 print $OUT "Stack dump during die enabled", 8665 ( $dieLevel == 1 ? " outside of evals" : "" ), ".\n" 8666 if $I_m_init; 8667 8668 # XXX This is probably obsolete, given that diehard() is gone. 8669 print $OUT "Dump printed too.\n" if $dieLevel > 2; 8670 } ## end if ($dieLevel) 8671 8672 # Put the old one back if there was one. 8673 elsif ($prevdie) { 8674 $SIG{__DIE__} = $prevdie; 8675 print $OUT "Default die handler restored.\n"; 8676 } else { 8677 undef $SIG{__DIE__}; 8678 print $OUT "Die handler removed.\n"; 8679 } 8680 } ## end if (@_) 8681 $dieLevel; 8682} ## end sub dieLevel 8683 8684=head2 C<signalLevel> 8685 8686Number three in a series: set C<signalLevel> to zero to keep your own 8687signal handler for C<SIGSEGV> and/or C<SIGBUS>. Otherwise, the debugger 8688takes over and handles them with C<DB::diesignal()>. 8689 8690=cut 8691 8692sub signalLevel { 8693 if (@_) { 8694 my $prevsegv = $SIG{SEGV} unless $signalLevel; 8695 my $prevbus = $SIG{BUS} unless $signalLevel; 8696 $signalLevel = shift; 8697 if ($signalLevel) { 8698 $SIG{SEGV} = \&DB::diesignal; 8699 $SIG{BUS} = \&DB::diesignal; 8700 } 8701 else { 8702 $SIG{SEGV} = $prevsegv; 8703 $SIG{BUS} = $prevbus; 8704 } 8705 } ## end if (@_) 8706 $signalLevel; 8707} ## end sub signalLevel 8708 8709=head1 SUBROUTINE DECODING SUPPORT 8710 8711These subroutines are used during the C<x> and C<X> commands to try to 8712produce as much information as possible about a code reference. They use 8713L<Devel::Peek> to try to find the glob in which this code reference lives 8714(if it does) - this allows us to actually code references which correspond 8715to named subroutines (including those aliased via glob assignment). 8716 8717=head2 C<CvGV_name()> 8718 8719Wrapper for C<CvGV_name_or_bust>; tries to get the name of a reference 8720via that routine. If this fails, return the reference again (when the 8721reference is stringified, it'll come out as C<SOMETHING(0x...)>). 8722 8723=cut 8724 8725sub CvGV_name { 8726 my $in = shift; 8727 my $name = CvGV_name_or_bust($in); 8728 defined $name ? $name : $in; 8729} 8730 8731=head2 C<CvGV_name_or_bust> I<coderef> 8732 8733Calls L<Devel::Peek> to try to find the glob the ref lives in; returns 8734C<undef> if L<Devel::Peek> can't be loaded, or if C<Devel::Peek::CvGV> can't 8735find a glob for this ref. 8736 8737Returns C<< I<package>::I<glob name> >> if the code ref is found in a glob. 8738 8739=cut 8740 8741use vars qw($skipCvGV); 8742 8743sub CvGV_name_or_bust { 8744 my $in = shift; 8745 return if $skipCvGV; # Backdoor to avoid problems if XS broken... 8746 return unless ref $in; 8747 $in = \&$in; # Hard reference... 8748 eval { require Devel::Peek; 1 } or return; 8749 my $gv = Devel::Peek::CvGV($in) or return; 8750 *$gv{PACKAGE} . '::' . *$gv{NAME}; 8751} ## end sub CvGV_name_or_bust 8752 8753=head2 C<find_sub> 8754 8755A utility routine used in various places; finds the file where a subroutine 8756was defined, and returns that filename and a line-number range. 8757 8758Tries to use C<@sub> first; if it can't find it there, it tries building a 8759reference to the subroutine and uses C<CvGV_name_or_bust> to locate it, 8760loading it into C<@sub> as a side effect (XXX I think). If it can't find it 8761this way, it brute-force searches C<%sub>, checking for identical references. 8762 8763=cut 8764 8765sub _find_sub_helper { 8766 my $subr = shift; 8767 8768 return unless defined &$subr; 8769 my $name = CvGV_name_or_bust($subr); 8770 my $data; 8771 $data = $sub{$name} if defined $name; 8772 return $data if defined $data; 8773 8774 # Old stupid way... 8775 $subr = \&$subr; # Hard reference 8776 my $s; 8777 for ( keys %sub ) { 8778 $s = $_, last if $subr eq \&$_; 8779 } 8780 if ($s) 8781 { 8782 return $sub{$s}; 8783 } 8784 else 8785 { 8786 return; 8787 } 8788 8789} 8790 8791sub find_sub { 8792 my $subr = shift; 8793 return ( $sub{$subr} || _find_sub_helper($subr) ); 8794} ## end sub find_sub 8795 8796=head2 C<methods> 8797 8798A subroutine that uses the utility function C<methods_via> to find all the 8799methods in the class corresponding to the current reference and in 8800C<UNIVERSAL>. 8801 8802=cut 8803 8804use vars qw(%seen); 8805 8806sub methods { 8807 8808 # Figure out the class - either this is the class or it's a reference 8809 # to something blessed into that class. 8810 my $class = shift; 8811 $class = ref $class if ref $class; 8812 8813 local %seen; 8814 8815 # Show the methods that this class has. 8816 methods_via( $class, '', 1 ); 8817 8818 # Show the methods that UNIVERSAL has. 8819 methods_via( 'UNIVERSAL', 'UNIVERSAL', 0 ); 8820} ## end sub methods 8821 8822=head2 C<methods_via($class, $prefix, $crawl_upward)> 8823 8824C<methods_via> does the work of crawling up the C<@ISA> tree and reporting 8825all the parent class methods. C<$class> is the name of the next class to 8826try; C<$prefix> is the message prefix, which gets built up as we go up the 8827C<@ISA> tree to show parentage; C<$crawl_upward> is 1 if we should try to go 8828higher in the C<@ISA> tree, 0 if we should stop. 8829 8830=cut 8831 8832sub methods_via { 8833 8834 # If we've processed this class already, just quit. 8835 my $class = shift; 8836 return if $seen{$class}++; 8837 8838 # This is a package that is contributing the methods we're about to print. 8839 my $prefix = shift; 8840 my $prepend = $prefix ? "via $prefix: " : ''; 8841 my @to_print; 8842 8843 # Extract from all the symbols in this class. 8844 my $class_ref = do { no strict "refs"; \%{$class . '::'} }; 8845 while (my ($name, $glob) = each %$class_ref) { 8846 # references directly in the symbol table are Proxy Constant 8847 # Subroutines, and are by their very nature defined 8848 # Otherwise, check if the thing is a typeglob, and if it is, it decays 8849 # to a subroutine reference, which can be tested by defined. 8850 # $glob might also be the value -1 (from sub foo;) 8851 # or (say) '$$' (from sub foo ($$);) 8852 # \$glob will be SCALAR in both cases. 8853 if ((ref $glob || ($glob && ref \$glob eq 'GLOB' && defined &$glob)) 8854 && !$seen{$name}++) { 8855 push @to_print, "$prepend$name\n"; 8856 } 8857 } 8858 8859 { 8860 local $\ = ''; 8861 local $, = ''; 8862 print $DB::OUT $_ foreach sort @to_print; 8863 } 8864 8865 # If the $crawl_upward argument is false, just quit here. 8866 return unless shift; 8867 8868 # $crawl_upward true: keep going up the tree. 8869 # Find all the classes this one is a subclass of. 8870 my $class_ISA_ref = do { no strict "refs"; \@{"${class}::ISA"} }; 8871 for my $name ( @$class_ISA_ref ) { 8872 8873 # Set up the new prefix. 8874 $prepend = $prefix ? $prefix . " -> $name" : $name; 8875 8876 # Crawl up the tree and keep trying to crawl up. 8877 methods_via( $name, $prepend, 1 ); 8878 } 8879} ## end sub methods_via 8880 8881=head2 C<setman> - figure out which command to use to show documentation 8882 8883Just checks the contents of C<$^O> and sets the C<$doccmd> global accordingly. 8884 8885=cut 8886 8887sub setman { 8888 $doccmd = $^O !~ /^(?:MSWin32|VMS|os2|dos|amigaos|riscos|NetWare)\z/s 8889 ? "man" # O Happy Day! 8890 : "perldoc"; # Alas, poor unfortunates 8891} ## end sub setman 8892 8893=head2 C<runman> - run the appropriate command to show documentation 8894 8895Accepts a man page name; runs the appropriate command to display it (set up 8896during debugger initialization). Uses C<_db_system()> to avoid mucking up the 8897program's STDIN and STDOUT. 8898 8899=cut 8900 8901my %_is_in_pods = (map { $_ => 1 } 8902 qw( 8903 5004delta 8904 5005delta 8905 561delta 8906 56delta 8907 570delta 8908 571delta 8909 572delta 8910 573delta 8911 58delta 8912 581delta 8913 582delta 8914 583delta 8915 584delta 8916 590delta 8917 591delta 8918 592delta 8919 aix 8920 amiga 8921 apio 8922 api 8923 artistic 8924 book 8925 boot 8926 bot 8927 bs2000 8928 call 8929 ce 8930 cheat 8931 clib 8932 cn 8933 compile 8934 cygwin 8935 data 8936 dbmfilter 8937 debguts 8938 debtut 8939 debug 8940 delta 8941 dgux 8942 diag 8943 doc 8944 dos 8945 dsc 8946 ebcdic 8947 embed 8948 faq1 8949 faq2 8950 faq3 8951 faq4 8952 faq5 8953 faq6 8954 faq7 8955 faq8 8956 faq9 8957 faq 8958 filter 8959 fork 8960 form 8961 freebsd 8962 func 8963 gpl 8964 guts 8965 hack 8966 hist 8967 hpux 8968 hurd 8969 intern 8970 intro 8971 iol 8972 ipc 8973 irix 8974 jp 8975 ko 8976 lexwarn 8977 locale 8978 lol 8979 macos 8980 macosx 8981 modinstall 8982 modlib 8983 mod 8984 modstyle 8985 netware 8986 newmod 8987 number 8988 obj 8989 opentut 8990 op 8991 os2 8992 os390 8993 os400 8994 packtut 8995 plan9 8996 pod 8997 podspec 8998 port 8999 qnx 9000 ref 9001 reftut 9002 re 9003 requick 9004 reref 9005 retut 9006 run 9007 sec 9008 solaris 9009 style 9010 sub 9011 syn 9012 thrtut 9013 tie 9014 toc 9015 todo 9016 tooc 9017 toot 9018 trap 9019 tru64 9020 tw 9021 unicode 9022 uniintro 9023 util 9024 uts 9025 var 9026 vms 9027 vos 9028 win32 9029 xs 9030 xstut 9031 ) 9032); 9033 9034sub runman { 9035 my $page = shift; 9036 unless ($page) { 9037 _db_system("$doccmd $doccmd"); 9038 return; 9039 } 9040 9041 # this way user can override, like with $doccmd="man -Mwhatever" 9042 # or even just "man " to disable the path check. 9043 if ( $doccmd ne 'man' ) { 9044 _db_system("$doccmd $page"); 9045 return; 9046 } 9047 9048 $page = 'perl' if lc($page) eq 'help'; 9049 9050 require Config; 9051 my $man1dir = $Config::Config{'man1dir'}; 9052 my $man3dir = $Config::Config{'man3dir'}; 9053 for ( $man1dir, $man3dir ) { s#/[^/]*\z## if /\S/ } 9054 my $manpath = ''; 9055 $manpath .= "$man1dir:" if $man1dir =~ /\S/; 9056 $manpath .= "$man3dir:" if $man3dir =~ /\S/ && $man1dir ne $man3dir; 9057 chop $manpath if $manpath; 9058 9059 # harmless if missing, I figure 9060 my $oldpath = $ENV{MANPATH}; 9061 $ENV{MANPATH} = $manpath if $manpath; 9062 my $nopathopt = $^O =~ /dunno what goes here/; 9063 if ( 9064 CORE::system( 9065 $doccmd, 9066 9067 # I just *know* there are men without -M 9068 ( ( $manpath && !$nopathopt ) ? ( "-M", $manpath ) : () ), 9069 split ' ', $page 9070 ) 9071 ) 9072 { 9073 unless ( $page =~ /^perl\w/ ) { 9074# do it this way because its easier to slurp in to keep up to date - clunky though. 9075 if (exists($_is_in_pods{$page})) { 9076 CORE::system( $doccmd, 9077 ( ( $manpath && !$nopathopt ) ? ( "-M", $manpath ) : () ), 9078 "perl$page" ); 9079 } 9080 } 9081 } ## end if (CORE::system($doccmd... 9082 if ( defined $oldpath ) { 9083 $ENV{MANPATH} = $manpath; 9084 } 9085 else { 9086 delete $ENV{MANPATH}; 9087 } 9088} ## end sub runman 9089 9090#use Carp; # This did break, left for debugging 9091 9092=head1 DEBUGGER INITIALIZATION - THE SECOND BEGIN BLOCK 9093 9094Because of the way the debugger interface to the Perl core is designed, any 9095debugger package globals that C<DB::sub()> requires have to be defined before 9096any subroutines can be called. These are defined in the second C<BEGIN> block. 9097 9098This block sets things up so that (basically) the world is sane 9099before the debugger starts executing. We set up various variables that the 9100debugger has to have set up before the Perl core starts running: 9101 9102=over 4 9103 9104=item * 9105 9106The debugger's own filehandles (copies of STD and STDOUT for now). 9107 9108=item * 9109 9110Characters for shell escapes, the recall command, and the history command. 9111 9112=item * 9113 9114The maximum recursion depth. 9115 9116=item * 9117 9118The size of a C<w> command's window. 9119 9120=item * 9121 9122The before-this-line context to be printed in a C<v> (view a window around this line) command. 9123 9124=item * 9125 9126The fact that we're not in a sub at all right now. 9127 9128=item * 9129 9130The default SIGINT handler for the debugger. 9131 9132=item * 9133 9134The appropriate value of the flag in C<$^D> that says the debugger is running 9135 9136=item * 9137 9138The current debugger recursion level 9139 9140=item * 9141 9142The list of postponed items and the C<$single> stack (XXX define this) 9143 9144=item * 9145 9146That we want no return values and no subroutine entry/exit trace. 9147 9148=back 9149 9150=cut 9151 9152# The following BEGIN is very handy if debugger goes havoc, debugging debugger? 9153 9154use vars qw($db_stop); 9155 9156BEGIN { # This does not compile, alas. (XXX eh?) 9157 $IN = \*STDIN; # For bugs before DB::OUT has been opened 9158 $OUT = \*STDERR; # For errors before DB::OUT has been opened 9159 9160 # Define characters used by command parsing. 9161 $sh = '!'; # Shell escape (does not work) 9162 $rc = ','; # Recall command (does not work) 9163 @hist = ('?'); # Show history (does not work) 9164 @truehist = (); # Can be saved for replay (per session) 9165 9166 # This defines the point at which you get the 'deep recursion' 9167 # warning. It MUST be defined or the debugger will not load. 9168 $deep = 100; 9169 9170 # Number of lines around the current one that are shown in the 9171 # 'w' command. 9172 $window = 10; 9173 9174 # How much before-the-current-line context the 'v' command should 9175 # use in calculating the start of the window it will display. 9176 $preview = 3; 9177 9178 # We're not in any sub yet, but we need this to be a defined value. 9179 $sub = ''; 9180 9181 # Set up the debugger's interrupt handler. It simply sets a flag 9182 # ($signal) that DB::DB() will check before each command is executed. 9183 $SIG{INT} = \&DB::catch; 9184 9185 # The following lines supposedly, if uncommented, allow the debugger to 9186 # debug itself. Perhaps we can try that someday. 9187 # This may be enabled to debug debugger: 9188 #$warnLevel = 1 unless defined $warnLevel; 9189 #$dieLevel = 1 unless defined $dieLevel; 9190 #$signalLevel = 1 unless defined $signalLevel; 9191 9192 # This is the flag that says "a debugger is running, please call 9193 # DB::DB and DB::sub". We will turn it on forcibly before we try to 9194 # execute anything in the user's context, because we always want to 9195 # get control back. 9196 $db_stop = 0; # Compiler warning ... 9197 $db_stop = 1 << 30; # ... because this is only used in an eval() later. 9198 9199 # This variable records how many levels we're nested in debugging. Used 9200 # Used in the debugger prompt, and in determining whether it's all over or 9201 # not. 9202 $level = 0; # Level of recursive debugging 9203 9204 # "Triggers bug (?) in perl if we postpone this until runtime." 9205 # XXX No details on this yet, or whether we should fix the bug instead 9206 # of work around it. Stay tuned. 9207 @stack = (0); 9208 9209 # Used to track the current stack depth using the auto-stacked-variable 9210 # trick. 9211 $stack_depth = 0; # Localized repeatedly; simple way to track $#stack 9212 9213 # Don't print return values on exiting a subroutine. 9214 $doret = -2; 9215 9216 # No extry/exit tracing. 9217 $frame = 0; 9218 9219} ## end BEGIN 9220 9221BEGIN { $^W = $ini_warn; } # Switch warnings back 9222 9223=head1 READLINE SUPPORT - COMPLETION FUNCTION 9224 9225=head2 db_complete 9226 9227C<readline> support - adds command completion to basic C<readline>. 9228 9229Returns a list of possible completions to C<readline> when invoked. C<readline> 9230will print the longest common substring following the text already entered. 9231 9232If there is only a single possible completion, C<readline> will use it in full. 9233 9234This code uses C<map> and C<grep> heavily to create lists of possible 9235completion. Think LISP in this section. 9236 9237=cut 9238 9239sub db_complete { 9240 9241 # Specific code for b c l V m f O, &blah, $blah, @blah, %blah 9242 # $text is the text to be completed. 9243 # $line is the incoming line typed by the user. 9244 # $start is the start of the text to be completed in the incoming line. 9245 my ( $text, $line, $start ) = @_; 9246 9247 # Save the initial text. 9248 # The search pattern is current package, ::, extract the next qualifier 9249 # Prefix and pack are set to undef. 9250 my ( $itext, $search, $prefix, $pack ) = 9251 ( $text, "^\Q${package}::\E([^:]+)\$" ); 9252 9253=head3 C<b postpone|compile> 9254 9255=over 4 9256 9257=item * 9258 9259Find all the subroutines that might match in this package 9260 9261=item * 9262 9263Add C<postpone>, C<load>, and C<compile> as possibles (we may be completing the keyword itself) 9264 9265=item * 9266 9267Include all the rest of the subs that are known 9268 9269=item * 9270 9271C<grep> out the ones that match the text we have so far 9272 9273=item * 9274 9275Return this as the list of possible completions 9276 9277=back 9278 9279=cut 9280 9281 return sort grep /^\Q$text/, ( keys %sub ), 9282 qw(postpone load compile), # subroutines 9283 ( map { /$search/ ? ($1) : () } keys %sub ) 9284 if ( substr $line, 0, $start ) =~ /^\|*[blc]\s+((postpone|compile)\s+)?$/; 9285 9286=head3 C<b load> 9287 9288Get all the possible files from C<@INC> as it currently stands and 9289select the ones that match the text so far. 9290 9291=cut 9292 9293 return sort grep /^\Q$text/, values %INC # files 9294 if ( substr $line, 0, $start ) =~ /^\|*b\s+load\s+$/; 9295 9296=head3 C<V> (list variable) and C<m> (list modules) 9297 9298There are two entry points for these commands: 9299 9300=head4 Unqualified package names 9301 9302Get the top-level packages and grab everything that matches the text 9303so far. For each match, recursively complete the partial packages to 9304get all possible matching packages. Return this sorted list. 9305 9306=cut 9307 9308 return sort map { ( $_, db_complete( $_ . "::", "V ", 2 ) ) } 9309 grep /^\Q$text/, map { /^(.*)::$/ ? ($1) : () } keys %:: # top-packages 9310 if ( substr $line, 0, $start ) =~ /^\|*[Vm]\s+$/ and $text =~ /^\w*$/; 9311 9312=head4 Qualified package names 9313 9314Take a partially-qualified package and find all subpackages for it 9315by getting all the subpackages for the package so far, matching all 9316the subpackages against the text, and discarding all of them which 9317start with 'main::'. Return this list. 9318 9319=cut 9320 9321 return sort map { ( $_, db_complete( $_ . "::", "V ", 2 ) ) } 9322 grep !/^main::/, grep /^\Q$text/, 9323 map { /^(.*)::$/ ? ( $prefix . "::$1" ) : () } 9324 do { no strict 'refs'; keys %{ $prefix . '::' } } 9325 if ( substr $line, 0, $start ) =~ /^\|*[Vm]\s+$/ 9326 and $text =~ /^(.*[^:])::?(\w*)$/ 9327 and $prefix = $1; 9328 9329=head3 C<f> - switch files 9330 9331Here, we want to get a fully-qualified filename for the C<f> command. 9332Possibilities are: 9333 9334=over 4 9335 9336=item 1. The original source file itself 9337 9338=item 2. A file from C<@INC> 9339 9340=item 3. An C<eval> (the debugger gets a C<(eval N)> fake file for each C<eval>). 9341 9342=back 9343 9344=cut 9345 9346 if ( $line =~ /^\|*f\s+(.*)/ ) { # Loaded files 9347 # We might possibly want to switch to an eval (which has a "filename" 9348 # like '(eval 9)'), so we may need to clean up the completion text 9349 # before proceeding. 9350 $prefix = length($1) - length($text); 9351 $text = $1; 9352 9353=pod 9354 9355Under the debugger, source files are represented as C<_E<lt>/fullpath/to/file> 9356(C<eval>s are C<_E<lt>(eval NNN)>) keys in C<%main::>. We pull all of these 9357out of C<%main::>, add the initial source file, and extract the ones that 9358match the completion text so far. 9359 9360=cut 9361 9362 return sort 9363 map { substr $_, 2 + $prefix } grep /^_<\Q$text/, ( keys %main:: ), 9364 $0; 9365 } ## end if ($line =~ /^\|*f\s+(.*)/) 9366 9367=head3 Subroutine name completion 9368 9369We look through all of the defined subs (the keys of C<%sub>) and 9370return both all the possible matches to the subroutine name plus 9371all the matches qualified to the current package. 9372 9373=cut 9374 9375 if ( ( substr $text, 0, 1 ) eq '&' ) { # subroutines 9376 $text = substr $text, 1; 9377 $prefix = "&"; 9378 return sort map "$prefix$_", grep /^\Q$text/, ( keys %sub ), 9379 ( 9380 map { /$search/ ? ($1) : () } 9381 keys %sub 9382 ); 9383 } ## end if ((substr $text, 0, ... 9384 9385=head3 Scalar, array, and hash completion: partially qualified package 9386 9387Much like the above, except we have to do a little more cleanup: 9388 9389=cut 9390 9391 if ( $text =~ /^[\$@%](.*)::(.*)/ ) { # symbols in a package 9392 9393=pod 9394 9395=over 4 9396 9397=item * 9398 9399Determine the package that the symbol is in. Put it in C<::> (effectively C<main::>) if no package is specified. 9400 9401=cut 9402 9403 $pack = ( $1 eq 'main' ? '' : $1 ) . '::'; 9404 9405=pod 9406 9407=item * 9408 9409Figure out the prefix vs. what needs completing. 9410 9411=cut 9412 9413 $prefix = ( substr $text, 0, 1 ) . $1 . '::'; 9414 $text = $2; 9415 9416=pod 9417 9418=item * 9419 9420Look through all the symbols in the package. C<grep> out all the possible hashes/arrays/scalars, and then C<grep> the possible matches out of those. C<map> the prefix onto all the possibilities. 9421 9422=cut 9423 9424 my @out = do { 9425 no strict 'refs'; 9426 map "$prefix$_", grep /^\Q$text/, grep /^_?[a-zA-Z]/, 9427 keys %$pack; 9428 }; 9429 9430=pod 9431 9432=item * 9433 9434If there's only one hit, and it's a package qualifier, and it's not equal to the initial text, re-complete it using the symbol we actually found. 9435 9436=cut 9437 9438 if ( @out == 1 and $out[0] =~ /::$/ and $out[0] ne $itext ) { 9439 return db_complete( $out[0], $line, $start ); 9440 } 9441 9442 # Return the list of possibles. 9443 return sort @out; 9444 9445 } ## end if ($text =~ /^[\$@%](.*)::(.*)/) 9446 9447=pod 9448 9449=back 9450 9451=head3 Symbol completion: current package or package C<main>. 9452 9453=cut 9454 9455 if ( $text =~ /^[\$@%]/ ) { # symbols (in $package + packages in main) 9456=pod 9457 9458=over 4 9459 9460=item * 9461 9462If it's C<main>, delete main to just get C<::> leading. 9463 9464=cut 9465 9466 $pack = ( $package eq 'main' ? '' : $package ) . '::'; 9467 9468=pod 9469 9470=item * 9471 9472We set the prefix to the item's sigil, and trim off the sigil to get the text to be completed. 9473 9474=cut 9475 9476 $prefix = substr $text, 0, 1; 9477 $text = substr $text, 1; 9478 9479 my @out; 9480 9481=pod 9482 9483=item * 9484 9485We look for the lexical scope above DB::DB and auto-complete lexical variables 9486if PadWalker could be loaded. 9487 9488=cut 9489 9490 if (not $text =~ /::/ and eval { require PadWalker } ) { 9491 my $level = 1; 9492 while (1) { 9493 my @info = caller($level); 9494 $level++; 9495 $level = -1, last 9496 if not @info; 9497 last if $info[3] eq 'DB::DB'; 9498 } 9499 if ($level > 0) { 9500 my $lexicals = PadWalker::peek_my($level); 9501 push @out, grep /^\Q$prefix$text/, keys %$lexicals; 9502 } 9503 } 9504 9505=pod 9506 9507=item * 9508 9509If the package is C<::> (C<main>), create an empty list; if it's something else, create a list of all the packages known. Append whichever list to a list of all the possible symbols in the current package. C<grep> out the matches to the text entered so far, then C<map> the prefix back onto the symbols. 9510 9511=cut 9512 9513 push @out, map "$prefix$_", grep /^\Q$text/, 9514 ( grep /^_?[a-zA-Z]/, keys %$pack ), 9515 ( $pack eq '::' ? () : ( grep /::$/, keys %:: ) ); 9516 9517=item * 9518 9519If there's only one hit, it's a package qualifier, and it's not equal to the initial text, recomplete using this symbol. 9520 9521=back 9522 9523=cut 9524 9525 if ( @out == 1 and $out[0] =~ /::$/ and $out[0] ne $itext ) { 9526 return db_complete( $out[0], $line, $start ); 9527 } 9528 9529 # Return the list of possibles. 9530 return sort @out; 9531 } ## end if ($text =~ /^[\$@%]/) 9532 9533=head3 Options 9534 9535We use C<option_val()> to look up the current value of the option. If there's 9536only a single value, we complete the command in such a way that it is a 9537complete command for setting the option in question. If there are multiple 9538possible values, we generate a command consisting of the option plus a trailing 9539question mark, which, if executed, will list the current value of the option. 9540 9541=cut 9542 9543 if ( ( substr $line, 0, $start ) =~ /^\|*[oO]\b.*\s$/ ) 9544 { # Options after space 9545 # We look for the text to be matched in the list of possible options, 9546 # and fetch the current value. 9547 my @out = grep /^\Q$text/, @options; 9548 my $val = option_val( $out[0], undef ); 9549 9550 # Set up a 'query option's value' command. 9551 my $out = '? '; 9552 if ( not defined $val or $val =~ /[\n\r]/ ) { 9553 9554 # There's really nothing else we can do. 9555 } 9556 9557 # We have a value. Create a proper option-setting command. 9558 elsif ( $val =~ /\s/ ) { 9559 9560 # XXX This may be an extraneous variable. 9561 my $found; 9562 9563 # We'll want to quote the string (because of the embedded 9564 # whtespace), but we want to make sure we don't end up with 9565 # mismatched quote characters. We try several possibilities. 9566 foreach my $l ( split //, qq/\"\'\#\|/ ) { 9567 9568 # If we didn't find this quote character in the value, 9569 # quote it using this quote character. 9570 $out = "$l$val$l ", last if ( index $val, $l ) == -1; 9571 } 9572 } ## end elsif ($val =~ /\s/) 9573 9574 # Don't need any quotes. 9575 else { 9576 $out = "=$val "; 9577 } 9578 9579 # If there were multiple possible values, return '? ', which 9580 # makes the command into a query command. If there was just one, 9581 # have readline append that. 9582 $rl_attribs->{completer_terminator_character} = 9583 ( @out == 1 ? $out : '? ' ); 9584 9585 # Return list of possibilities. 9586 return sort @out; 9587 } ## end if ((substr $line, 0, ... 9588 9589=head3 Filename completion 9590 9591For entering filenames. We simply call C<readline>'s C<filename_list()> 9592method with the completion text to get the possible completions. 9593 9594=cut 9595 9596 return $term->filename_list($text); # filenames 9597 9598} ## end sub db_complete 9599 9600=head1 MISCELLANEOUS SUPPORT FUNCTIONS 9601 9602Functions that possibly ought to be somewhere else. 9603 9604=head2 end_report 9605 9606Say we're done. 9607 9608=cut 9609 9610sub end_report { 9611 local $\ = ''; 9612 print $OUT "Use 'q' to quit or 'R' to restart. 'h q' for details.\n"; 9613} 9614 9615=head2 clean_ENV 9616 9617If we have $ini_pids, save it in the environment; else remove it from the 9618environment. Used by the C<R> (restart) command. 9619 9620=cut 9621 9622sub clean_ENV { 9623 if ( defined($ini_pids) ) { 9624 $ENV{PERLDB_PIDS} = $ini_pids; 9625 } 9626 else { 9627 delete( $ENV{PERLDB_PIDS} ); 9628 } 9629} ## end sub clean_ENV 9630 9631# PERLDBf_... flag names from perl.h 9632our ( %DollarCaretP_flags, %DollarCaretP_flags_r ); 9633 9634BEGIN { 9635 %DollarCaretP_flags = ( 9636 PERLDBf_SUB => 0x01, # Debug sub enter/exit 9637 PERLDBf_LINE => 0x02, # Keep line # 9638 PERLDBf_NOOPT => 0x04, # Switch off optimizations 9639 PERLDBf_INTER => 0x08, # Preserve more data 9640 PERLDBf_SUBLINE => 0x10, # Keep subr source lines 9641 PERLDBf_SINGLE => 0x20, # Start with single-step on 9642 PERLDBf_NONAME => 0x40, # For _SUB: no name of the subr 9643 PERLDBf_GOTO => 0x80, # Report goto: call DB::goto 9644 PERLDBf_NAMEEVAL => 0x100, # Informative names for evals 9645 PERLDBf_NAMEANON => 0x200, # Informative names for anon subs 9646 PERLDBf_SAVESRC => 0x400, # Save source lines into @{"_<$filename"} 9647 PERLDB_ALL => 0x33f, # No _NONAME, _GOTO 9648 ); 9649 # PERLDBf_LINE also enables the actions of PERLDBf_SAVESRC, so the debugger 9650 # doesn't need to set it. It's provided for the benefit of profilers and 9651 # other code analysers. 9652 9653 %DollarCaretP_flags_r = reverse %DollarCaretP_flags; 9654} 9655 9656sub parse_DollarCaretP_flags { 9657 my $flags = shift; 9658 $flags =~ s/^\s+//; 9659 $flags =~ s/\s+$//; 9660 my $acu = 0; 9661 foreach my $f ( split /\s*\|\s*/, $flags ) { 9662 my $value; 9663 if ( $f =~ /^0x([[:xdigit:]]+)$/ ) { 9664 $value = hex $1; 9665 } 9666 elsif ( $f =~ /^(\d+)$/ ) { 9667 $value = int $1; 9668 } 9669 elsif ( $f =~ /^DEFAULT$/i ) { 9670 $value = $DollarCaretP_flags{PERLDB_ALL}; 9671 } 9672 else { 9673 $f =~ /^(?:PERLDBf_)?(.*)$/i; 9674 $value = $DollarCaretP_flags{ 'PERLDBf_' . uc($1) }; 9675 unless ( defined $value ) { 9676 print $OUT ( 9677 "Unrecognized \$^P flag '$f'!\n", 9678 "Acceptable flags are: " 9679 . join( ', ', sort keys %DollarCaretP_flags ), 9680 ", and hexadecimal and decimal numbers.\n" 9681 ); 9682 return undef; 9683 } 9684 } 9685 $acu |= $value; 9686 } 9687 $acu; 9688} 9689 9690sub expand_DollarCaretP_flags { 9691 my $DollarCaretP = shift; 9692 my @bits = ( 9693 map { 9694 my $n = ( 1 << $_ ); 9695 ( $DollarCaretP & $n ) 9696 ? ( $DollarCaretP_flags_r{$n} 9697 || sprintf( '0x%x', $n ) ) 9698 : () 9699 } 0 .. 31 9700 ); 9701 return @bits ? join( '|', @bits ) : 0; 9702} 9703 9704=over 4 9705 9706=item rerun 9707 9708Rerun the current session to: 9709 9710 rerun current position 9711 9712 rerun 4 command number 4 9713 9714 rerun -4 current command minus 4 (go back 4 steps) 9715 9716Whether this always makes sense, in the current context is unknowable, and is 9717in part left as a useful exercise for the reader. This sub returns the 9718appropriate arguments to rerun the current session. 9719 9720=cut 9721 9722sub rerun { 9723 my $i = shift; 9724 my @args; 9725 pop(@truehist); # strim 9726 unless (defined $truehist[$i]) { 9727 print "Unable to return to non-existent command: $i\n"; 9728 } else { 9729 $#truehist = ($i < 0 ? $#truehist + $i : $i > 0 ? $i : $#truehist); 9730 my @temp = @truehist; # store 9731 push(@DB::typeahead, @truehist); # saved 9732 @truehist = @hist = (); # flush 9733 @args = restart(); # setup 9734 get_list("PERLDB_HIST"); # clean 9735 set_list("PERLDB_HIST", @temp); # reset 9736 } 9737 return @args; 9738} 9739 9740=item restart 9741 9742Restarting the debugger is a complex operation that occurs in several phases. 9743First, we try to reconstruct the command line that was used to invoke Perl 9744and the debugger. 9745 9746=cut 9747 9748sub restart { 9749 # I may not be able to resurrect you, but here goes ... 9750 print $OUT 9751"Warning: some settings and command-line options may be lost!\n"; 9752 my ( @script, @flags, $cl ); 9753 9754 # If warn was on before, turn it on again. 9755 push @flags, '-w' if $ini_warn; 9756 9757 # Rebuild the -I flags that were on the initial 9758 # command line. 9759 for (@ini_INC) { 9760 push @flags, '-I', $_; 9761 } 9762 9763 # Turn on taint if it was on before. 9764 push @flags, '-T' if ${^TAINT}; 9765 9766 # Arrange for setting the old INC: 9767 # Save the current @init_INC in the environment. 9768 set_list( "PERLDB_INC", @ini_INC ); 9769 9770 # If this was a perl one-liner, go to the "file" 9771 # corresponding to the one-liner read all the lines 9772 # out of it (except for the first one, which is going 9773 # to be added back on again when 'perl -d' runs: that's 9774 # the 'require perl5db.pl;' line), and add them back on 9775 # to the command line to be executed. 9776 if ( $0 eq '-e' ) { 9777 my $lines = *{$main::{'_<-e'}}{ARRAY}; 9778 for ( 1 .. $#$lines ) { # The first line is PERL5DB 9779 chomp( $cl = $lines->[$_] ); 9780 push @script, '-e', $cl; 9781 } 9782 } ## end if ($0 eq '-e') 9783 9784 # Otherwise we just reuse the original name we had 9785 # before. 9786 else { 9787 @script = $0; 9788 } 9789 9790=pod 9791 9792After the command line has been reconstructed, the next step is to save 9793the debugger's status in environment variables. The C<DB::set_list> routine 9794is used to save aggregate variables (both hashes and arrays); scalars are 9795just popped into environment variables directly. 9796 9797=cut 9798 9799 # If the terminal supported history, grab it and 9800 # save that in the environment. 9801 set_list( "PERLDB_HIST", 9802 $term->Features->{getHistory} 9803 ? $term->GetHistory 9804 : @hist ); 9805 9806 # Find all the files that were visited during this 9807 # session (i.e., the debugger had magic hashes 9808 # corresponding to them) and stick them in the environment. 9809 my @had_breakpoints = keys %had_breakpoints; 9810 set_list( "PERLDB_VISITED", @had_breakpoints ); 9811 9812 # Save the debugger options we chose. 9813 set_list( "PERLDB_OPT", %option ); 9814 # set_list( "PERLDB_OPT", options2remember() ); 9815 9816 # Save the break-on-loads. 9817 set_list( "PERLDB_ON_LOAD", %break_on_load ); 9818 9819=pod 9820 9821The most complex part of this is the saving of all of the breakpoints. They 9822can live in an awful lot of places, and we have to go through all of them, 9823find the breakpoints, and then save them in the appropriate environment 9824variable via C<DB::set_list>. 9825 9826=cut 9827 9828 # Go through all the breakpoints and make sure they're 9829 # still valid. 9830 my @hard; 9831 for ( 0 .. $#had_breakpoints ) { 9832 9833 # We were in this file. 9834 my $file = $had_breakpoints[$_]; 9835 9836 # Grab that file's magic line hash. 9837 *dbline = $main::{ '_<' . $file }; 9838 9839 # Skip out if it doesn't exist, or if the breakpoint 9840 # is in a postponed file (we'll do postponed ones 9841 # later). 9842 next unless %dbline or $postponed_file{$file}; 9843 9844 # In an eval. This is a little harder, so we'll 9845 # do more processing on that below. 9846 ( push @hard, $file ), next 9847 if $file =~ /^\(\w*eval/; 9848 9849 # XXX I have no idea what this is doing. Yet. 9850 my @add; 9851 @add = %{ $postponed_file{$file} } 9852 if $postponed_file{$file}; 9853 9854 # Save the list of all the breakpoints for this file. 9855 set_list( "PERLDB_FILE_$_", %dbline, @add ); 9856 9857 # Serialize the extra data %breakpoints_data hash. 9858 # That's a bug fix. 9859 set_list( "PERLDB_FILE_ENABLED_$_", 9860 map { _is_breakpoint_enabled($file, $_) ? 1 : 0 } 9861 sort { $a <=> $b } keys(%dbline) 9862 ) 9863 } ## end for (0 .. $#had_breakpoints) 9864 9865 # The breakpoint was inside an eval. This is a little 9866 # more difficult. XXX and I don't understand it. 9867 foreach my $hard_file (@hard) { 9868 # Get over to the eval in question. 9869 *dbline = $main::{ '_<' . $hard_file }; 9870 my $quoted = quotemeta $hard_file; 9871 my %subs; 9872 for my $sub ( keys %sub ) { 9873 if (my ($n1, $n2) = $sub{$sub} =~ /\A$quoted:(\d+)-(\d+)\z/) { 9874 $subs{$sub} = [ $n1, $n2 ]; 9875 } 9876 } 9877 unless (%subs) { 9878 print {$OUT} 9879 "No subroutines in $hard_file, ignoring breakpoints.\n"; 9880 next; 9881 } 9882 LINES: foreach my $line ( keys %dbline ) { 9883 9884 # One breakpoint per sub only: 9885 my ( $offset, $found ); 9886 SUBS: foreach my $sub ( keys %subs ) { 9887 if ( 9888 $subs{$sub}->[1] >= $line # Not after the subroutine 9889 and ( 9890 not defined $offset # Not caught 9891 or $offset < 0 9892 ) 9893 ) 9894 { # or badly caught 9895 $found = $sub; 9896 $offset = $line - $subs{$sub}->[0]; 9897 if ($offset >= 0) { 9898 $offset = "+$offset"; 9899 last SUBS; 9900 } 9901 } ## end if ($subs{$sub}->[1] >=... 9902 } ## end for $sub (keys %subs) 9903 if ( defined $offset ) { 9904 $postponed{$found} = 9905 "break $offset if $dbline{$line}"; 9906 } 9907 else { 9908 print {$OUT} 9909 ("Breakpoint in ${hard_file}:$line ignored:" 9910 . " after all the subroutines.\n"); 9911 } 9912 } ## end for $line (keys %dbline) 9913 } ## end for (@hard) 9914 9915 # Save the other things that don't need to be 9916 # processed. 9917 set_list( "PERLDB_POSTPONE", %postponed ); 9918 set_list( "PERLDB_PRETYPE", @$pretype ); 9919 set_list( "PERLDB_PRE", @$pre ); 9920 set_list( "PERLDB_POST", @$post ); 9921 set_list( "PERLDB_TYPEAHEAD", @typeahead ); 9922 9923 # We are officially restarting. 9924 $ENV{PERLDB_RESTART} = 1; 9925 9926 # We are junking all child debuggers. 9927 delete $ENV{PERLDB_PIDS}; # Restore ini state 9928 9929 # Set this back to the initial pid. 9930 $ENV{PERLDB_PIDS} = $ini_pids if defined $ini_pids; 9931 9932=pod 9933 9934After all the debugger status has been saved, we take the command we built up 9935and then return it, so we can C<exec()> it. The debugger will spot the 9936C<PERLDB_RESTART> environment variable and realize it needs to reload its state 9937from the environment. 9938 9939=cut 9940 9941 # And run Perl again. Add the "-d" flag, all the 9942 # flags we built up, the script (whether a one-liner 9943 # or a file), add on the -emacs flag for a slave editor, 9944 # and then the old arguments. 9945 9946 return ($^X, '-d', @flags, @script, ($slave_editor ? '-emacs' : ()), @ARGS); 9947 9948}; # end restart 9949 9950=back 9951 9952=head1 END PROCESSING - THE C<END> BLOCK 9953 9954Come here at the very end of processing. We want to go into a 9955loop where we allow the user to enter commands and interact with the 9956debugger, but we don't want anything else to execute. 9957 9958First we set the C<$finished> variable, so that some commands that 9959shouldn't be run after the end of program quit working. 9960 9961We then figure out whether we're truly done (as in the user entered a C<q> 9962command, or we finished execution while running nonstop). If we aren't, 9963we set C<$single> to 1 (causing the debugger to get control again). 9964 9965We then call C<DB::fake::at_exit()>, which returns the C<Use 'q' to quit ...> 9966message and returns control to the debugger. Repeat. 9967 9968When the user finally enters a C<q> command, C<$fall_off_end> is set to 99691 and the C<END> block simply exits with C<$single> set to 0 (don't 9970break, run to completion.). 9971 9972=cut 9973 9974END { 9975 $finished = 1 if $inhibit_exit; # So that some commands may be disabled. 9976 $fall_off_end = 1 unless $inhibit_exit; 9977 9978 # Do not stop in at_exit() and destructors on exit: 9979 if ($fall_off_end or $runnonstop) { 9980 save_hist(); 9981 } else { 9982 $DB::single = 1; 9983 DB::fake::at_exit(); 9984 } 9985} ## end END 9986 9987=head1 PRE-5.8 COMMANDS 9988 9989Some of the commands changed function quite a bit in the 5.8 command 9990realignment, so much so that the old code had to be replaced completely. 9991Because we wanted to retain the option of being able to go back to the 9992former command set, we moved the old code off to this section. 9993 9994There's an awful lot of duplicated code here. We've duplicated the 9995comments to keep things clear. 9996 9997=head2 Null command 9998 9999Does nothing. Used to I<turn off> commands. 10000 10001=cut 10002 10003sub cmd_pre580_null { 10004 10005 # do nothing... 10006} 10007 10008=head2 Old C<a> command. 10009 10010This version added actions if you supplied them, and deleted them 10011if you didn't. 10012 10013=cut 10014 10015sub cmd_pre580_a { 10016 my $xcmd = shift; 10017 my $cmd = shift; 10018 10019 # Argument supplied. Add the action. 10020 if ( $cmd =~ /^(\d*)\s*(.*)/ ) { 10021 10022 # If the line isn't there, use the current line. 10023 my $i = $1 || $line; 10024 my $j = $2; 10025 10026 # If there is an action ... 10027 if ( length $j ) { 10028 10029 # ... but the line isn't breakable, skip it. 10030 if ( $dbline[$i] == 0 ) { 10031 print $OUT "Line $i may not have an action.\n"; 10032 } 10033 else { 10034 10035 # ... and the line is breakable: 10036 # Mark that there's an action in this file. 10037 $had_breakpoints{$filename} |= 2; 10038 10039 # Delete any current action. 10040 $dbline{$i} =~ s/\0[^\0]*//; 10041 10042 # Add the new action, continuing the line as needed. 10043 $dbline{$i} .= "\0" . action($j); 10044 } 10045 } ## end if (length $j) 10046 10047 # No action supplied. 10048 else { 10049 10050 # Delete the action. 10051 $dbline{$i} =~ s/\0[^\0]*//; 10052 10053 # Mark as having no break or action if nothing's left. 10054 delete $dbline{$i} if $dbline{$i} eq ''; 10055 } 10056 } ## end if ($cmd =~ /^(\d*)\s*(.*)/) 10057} ## end sub cmd_pre580_a 10058 10059=head2 Old C<b> command 10060 10061Add breakpoints. 10062 10063=cut 10064 10065sub cmd_pre580_b { 10066 my $xcmd = shift; 10067 my $cmd = shift; 10068 my $dbline = shift; 10069 10070 # Break on load. 10071 if ( $cmd =~ /^load\b\s*(.*)/ ) { 10072 my $file = $1; 10073 $file =~ s/\s+$//; 10074 cmd_b_load($file); 10075 } 10076 10077 # b compile|postpone <some sub> [<condition>] 10078 # The interpreter actually traps this one for us; we just put the 10079 # necessary condition in the %postponed hash. 10080 elsif ( $cmd =~ /^(postpone|compile)\b\s*([':A-Za-z_][':\w]*)\s*(.*)/ ) { 10081 10082 # Capture the condition if there is one. Make it true if none. 10083 my $cond = length $3 ? $3 : '1'; 10084 10085 # Save the sub name and set $break to 1 if $1 was 'postpone', 0 10086 # if it was 'compile'. 10087 my ( $subname, $break ) = ( $2, $1 eq 'postpone' ); 10088 10089 # De-Perl4-ify the name - ' separators to ::. 10090 $subname =~ s/\'/::/g; 10091 10092 # Qualify it into the current package unless it's already qualified. 10093 $subname = "${package}::" . $subname 10094 unless $subname =~ /::/; 10095 10096 # Add main if it starts with ::. 10097 $subname = "main" . $subname if substr( $subname, 0, 2 ) eq "::"; 10098 10099 # Save the break type for this sub. 10100 $postponed{$subname} = $break ? "break +0 if $cond" : "compile"; 10101 } ## end elsif ($cmd =~ ... 10102 10103 # b <sub name> [<condition>] 10104 elsif ( $cmd =~ /^([':A-Za-z_][':\w]*(?:\[.*\])?)\s*(.*)/ ) { 10105 my $subname = $1; 10106 my $cond = length $2 ? $2 : '1'; 10107 cmd_b_sub( $subname, $cond ); 10108 } 10109 # b <line> [<condition>]. 10110 elsif ( $cmd =~ /^(\d*)\s*(.*)/ ) { 10111 my $i = $1 || $dbline; 10112 my $cond = length $2 ? $2 : '1'; 10113 cmd_b_line( $i, $cond ); 10114 } 10115} ## end sub cmd_pre580_b 10116 10117=head2 Old C<D> command. 10118 10119Delete all breakpoints unconditionally. 10120 10121=cut 10122 10123sub cmd_pre580_D { 10124 my $xcmd = shift; 10125 my $cmd = shift; 10126 if ( $cmd =~ /^\s*$/ ) { 10127 print $OUT "Deleting all breakpoints...\n"; 10128 10129 # %had_breakpoints lists every file that had at least one 10130 # breakpoint in it. 10131 my $file; 10132 for $file ( keys %had_breakpoints ) { 10133 10134 # Switch to the desired file temporarily. 10135 local *dbline = $main::{ '_<' . $file }; 10136 10137 $max = $#dbline; 10138 my $was; 10139 10140 # For all lines in this file ... 10141 for my $i (1 .. $max) { 10142 10143 # If there's a breakpoint or action on this line ... 10144 if ( defined $dbline{$i} ) { 10145 10146 # ... remove the breakpoint. 10147 $dbline{$i} =~ s/^[^\0]+//; 10148 if ( $dbline{$i} =~ s/^\0?$// ) { 10149 10150 # Remove the entry altogether if no action is there. 10151 delete $dbline{$i}; 10152 } 10153 } ## end if (defined $dbline{$i... 10154 } ## end for my $i (1 .. $max) 10155 10156 # If, after we turn off the "there were breakpoints in this file" 10157 # bit, the entry in %had_breakpoints for this file is zero, 10158 # we should remove this file from the hash. 10159 if ( not $had_breakpoints{$file} &= ~1 ) { 10160 delete $had_breakpoints{$file}; 10161 } 10162 } ## end for $file (keys %had_breakpoints) 10163 10164 # Kill off all the other breakpoints that are waiting for files that 10165 # haven't been loaded yet. 10166 undef %postponed; 10167 undef %postponed_file; 10168 undef %break_on_load; 10169 } ## end if ($cmd =~ /^\s*$/) 10170} ## end sub cmd_pre580_D 10171 10172=head2 Old C<h> command 10173 10174Print help. Defaults to printing the long-form help; the 5.8 version 10175prints the summary by default. 10176 10177=cut 10178 10179sub cmd_pre580_h { 10180 my $xcmd = shift; 10181 my $cmd = shift; 10182 10183 # Print the *right* help, long format. 10184 if ( $cmd =~ /^\s*$/ ) { 10185 print_help($pre580_help); 10186 } 10187 10188 # 'h h' - explicitly-requested summary. 10189 elsif ( $cmd =~ /^h\s*/ ) { 10190 print_help($pre580_summary); 10191 } 10192 10193 # Find and print a command's help. 10194 elsif ( $cmd =~ /^h\s+(\S.*)$/ ) { 10195 my $asked = $1; # for proper errmsg 10196 my $qasked = quotemeta($asked); # for searching 10197 # XXX: finds CR but not <CR> 10198 if ( 10199 $pre580_help =~ /^ 10200 <? # Optional '<' 10201 (?:[IB]<) # Optional markup 10202 $qasked # The command name 10203 /mx 10204 ) 10205 { 10206 10207 while ( 10208 $pre580_help =~ /^ 10209 ( # The command help: 10210 <? # Optional '<' 10211 (?:[IB]<) # Optional markup 10212 $qasked # The command name 10213 ([\s\S]*?) # Lines starting with tabs 10214 \n # Final newline 10215 ) 10216 (?!\s)/mgx 10217 ) # Line not starting with space 10218 # (Next command's help) 10219 { 10220 print_help($1); 10221 } 10222 } ## end if ($pre580_help =~ /^<?(?:[IB]<)$qasked/m) 10223 10224 # Help not found. 10225 else { 10226 print_help("B<$asked> is not a debugger command.\n"); 10227 } 10228 } ## end elsif ($cmd =~ /^h\s+(\S.*)$/) 10229} ## end sub cmd_pre580_h 10230 10231=head2 Old C<W> command 10232 10233C<W E<lt>exprE<gt>> adds a watch expression, C<W> deletes them all. 10234 10235=cut 10236 10237sub cmd_pre580_W { 10238 my $xcmd = shift; 10239 my $cmd = shift; 10240 10241 # Delete all watch expressions. 10242 if ( $cmd =~ /^$/ ) { 10243 10244 # No watching is going on. 10245 $trace &= ~2; 10246 10247 # Kill all the watch expressions and values. 10248 @to_watch = @old_watch = (); 10249 } 10250 10251 # Add a watch expression. 10252 elsif ( $cmd =~ /^(.*)/s ) { 10253 10254 # add it to the list to be watched. 10255 push @to_watch, $1; 10256 10257 # Get the current value of the expression. 10258 # Doesn't handle expressions returning list values! 10259 $evalarg = $1; 10260 # The &-call is here to ascertain the mutability of @_. 10261 my ($val) = &DB::eval; 10262 $val = ( defined $val ) ? "'$val'" : 'undef'; 10263 10264 # Save it. 10265 push @old_watch, $val; 10266 10267 # We're watching stuff. 10268 $trace |= 2; 10269 10270 } ## end elsif ($cmd =~ /^(.*)/s) 10271} ## end sub cmd_pre580_W 10272 10273=head1 PRE-AND-POST-PROMPT COMMANDS AND ACTIONS 10274 10275The debugger used to have a bunch of nearly-identical code to handle 10276the pre-and-post-prompt action commands. C<cmd_pre590_prepost> and 10277C<cmd_prepost> unify all this into one set of code to handle the 10278appropriate actions. 10279 10280=head2 C<cmd_pre590_prepost> 10281 10282A small wrapper around C<cmd_prepost>; it makes sure that the default doesn't 10283do something destructive. In pre 5.8 debuggers, the default action was to 10284delete all the actions. 10285 10286=cut 10287 10288sub cmd_pre590_prepost { 10289 my $cmd = shift; 10290 my $line = shift || '*'; 10291 my $dbline = shift; 10292 10293 return cmd_prepost( $cmd, $line, $dbline ); 10294} ## end sub cmd_pre590_prepost 10295 10296=head2 C<cmd_prepost> 10297 10298Actually does all the handling for C<E<lt>>, C<E<gt>>, C<{{>, C<{>, etc. 10299Since the lists of actions are all held in arrays that are pointed to by 10300references anyway, all we have to do is pick the right array reference and 10301then use generic code to all, delete, or list actions. 10302 10303=cut 10304 10305sub cmd_prepost { 10306 my $cmd = shift; 10307 10308 # No action supplied defaults to 'list'. 10309 my $line = shift || '?'; 10310 10311 # Figure out what to put in the prompt. 10312 my $which = ''; 10313 10314 # Make sure we have some array or another to address later. 10315 # This means that if ssome reason the tests fail, we won't be 10316 # trying to stash actions or delete them from the wrong place. 10317 my $aref = []; 10318 10319 # < - Perl code to run before prompt. 10320 if ( $cmd =~ /^\</o ) { 10321 $which = 'pre-perl'; 10322 $aref = $pre; 10323 } 10324 10325 # > - Perl code to run after prompt. 10326 elsif ( $cmd =~ /^\>/o ) { 10327 $which = 'post-perl'; 10328 $aref = $post; 10329 } 10330 10331 # { - first check for properly-balanced braces. 10332 elsif ( $cmd =~ /^\{/o ) { 10333 if ( $cmd =~ /^\{.*\}$/o && unbalanced( substr( $cmd, 1 ) ) ) { 10334 print $OUT 10335"$cmd is now a debugger command\nuse ';$cmd' if you mean Perl code\n"; 10336 } 10337 10338 # Properly balanced. Pre-prompt debugger actions. 10339 else { 10340 $which = 'pre-debugger'; 10341 $aref = $pretype; 10342 } 10343 } ## end elsif ( $cmd =~ /^\{/o ) 10344 10345 # Did we find something that makes sense? 10346 unless ($which) { 10347 print $OUT "Confused by command: $cmd\n"; 10348 } 10349 10350 # Yes. 10351 else { 10352 10353 # List actions. 10354 if ( $line =~ /^\s*\?\s*$/o ) { 10355 unless (@$aref) { 10356 10357 # Nothing there. Complain. 10358 print $OUT "No $which actions.\n"; 10359 } 10360 else { 10361 10362 # List the actions in the selected list. 10363 print $OUT "$which commands:\n"; 10364 foreach my $action (@$aref) { 10365 print $OUT "\t$cmd -- $action\n"; 10366 } 10367 } ## end else 10368 } ## end if ( $line =~ /^\s*\?\s*$/o) 10369 10370 # Might be a delete. 10371 else { 10372 if ( length($cmd) == 1 ) { 10373 if ( $line =~ /^\s*\*\s*$/o ) { 10374 10375 # It's a delete. Get rid of the old actions in the 10376 # selected list.. 10377 @$aref = (); 10378 print $OUT "All $cmd actions cleared.\n"; 10379 } 10380 else { 10381 10382 # Replace all the actions. (This is a <, >, or {). 10383 @$aref = action($line); 10384 } 10385 } ## end if ( length($cmd) == 1) 10386 elsif ( length($cmd) == 2 ) { 10387 10388 # Add the action to the line. (This is a <<, >>, or {{). 10389 push @$aref, action($line); 10390 } 10391 else { 10392 10393 # <<<, >>>>, {{{{{{ ... something not a command. 10394 print $OUT 10395 "Confused by strange length of $which command($cmd)...\n"; 10396 } 10397 } ## end else [ if ( $line =~ /^\s*\?\s*$/o) 10398 } ## end else 10399} ## end sub cmd_prepost 10400 10401=head1 C<DB::fake> 10402 10403Contains the C<at_exit> routine that the debugger uses to issue the 10404C<Debugged program terminated ...> message after the program completes. See 10405the C<END> block documentation for more details. 10406 10407=cut 10408 10409package DB::fake; 10410 10411sub at_exit { 10412 "Debugged program terminated. Use 'q' to quit or 'R' to restart."; 10413} 10414 10415package DB; # Do not trace this 1; below! 10416 104171; 10418 10419 10420