1 /* $NetBSD: csh.c,v 1.16 1997/01/13 17:53:15 tls Exp $ */ 2 3 /*- 4 * Copyright (c) 1980, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef lint 37 static char copyright[] = 38 "@(#) Copyright (c) 1980, 1991, 1993\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)csh.c 8.2 (Berkeley) 10/12/93"; 45 #else 46 static char rcsid[] = "$NetBSD: csh.c,v 1.16 1997/01/13 17:53:15 tls Exp $"; 47 #endif 48 #endif /* not lint */ 49 50 #include <sys/types.h> 51 #include <sys/ioctl.h> 52 #include <sys/stat.h> 53 #include <fcntl.h> 54 #include <errno.h> 55 #include <pwd.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <locale.h> 59 #include <unistd.h> 60 #include <vis.h> 61 #if __STDC__ 62 # include <stdarg.h> 63 #else 64 # include <varargs.h> 65 #endif 66 67 #include "csh.h" 68 #include "proc.h" 69 #include "extern.h" 70 #include "pathnames.h" 71 72 extern bool MapsAreInited; 73 extern bool NLSMapsAreInited; 74 75 /* 76 * C Shell 77 * 78 * Bill Joy, UC Berkeley, California, USA 79 * October 1978, May 1980 80 * 81 * Jim Kulp, IIASA, Laxenburg, Austria 82 * April 1980 83 * 84 * Christos Zoulas, Cornell University 85 * June, 1991 86 */ 87 88 Char *dumphist[] = {STRhistory, STRmh, 0, 0}; 89 Char *loadhist[] = {STRsource, STRmh, STRtildothist, 0}; 90 91 int nofile = 0; 92 bool reenter = 0; 93 bool nverbose = 0; 94 bool nexececho = 0; 95 bool quitit = 0; 96 bool fast = 0; 97 bool batch = 0; 98 bool mflag = 0; 99 bool prompt = 1; 100 bool enterhist = 0; 101 bool tellwhat = 0; 102 103 extern char **environ; 104 105 static int readf __P((void *, char *, int)); 106 static fpos_t seekf __P((void *, fpos_t, int)); 107 static int writef __P((void *, const char *, int)); 108 static int closef __P((void *)); 109 static int srccat __P((Char *, Char *)); 110 static int srcfile __P((char *, bool, bool)); 111 static void phup __P((int)); 112 static void srcunit __P((int, bool, bool)); 113 static void mailchk __P((void)); 114 static Char **defaultpath __P((void)); 115 116 int 117 main(argc, argv) 118 int argc; 119 char **argv; 120 { 121 Char *cp; 122 char *tcp; 123 int f; 124 char **tempv; 125 struct sigaction oact; 126 sigset_t sigset; 127 128 cshin = stdin; 129 cshout = stdout; 130 csherr = stderr; 131 132 settimes(); /* Immed. estab. timing base */ 133 134 /* 135 * Initialize non constant strings 136 */ 137 #ifdef _PATH_BSHELL 138 STR_BSHELL = SAVE(_PATH_BSHELL); 139 #endif 140 #ifdef _PATH_CSHELL 141 STR_SHELLPATH = SAVE(_PATH_CSHELL); 142 #endif 143 STR_environ = blk2short(environ); 144 environ = short2blk(STR_environ); /* So that we can free it */ 145 STR_WORD_CHARS = SAVE(WORD_CHARS); 146 147 HIST = '!'; 148 HISTSUB = '^'; 149 word_chars = STR_WORD_CHARS; 150 151 tempv = argv; 152 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 153 quitit = 1; 154 uid = getuid(); 155 gid = getgid(); 156 euid = geteuid(); 157 egid = getegid(); 158 /* 159 * We are a login shell if: 1. we were invoked as -<something> and we had 160 * no arguments 2. or we were invoked only with the -l flag 161 */ 162 loginsh = (**tempv == '-' && argc == 1) || 163 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 164 tempv[1][2] == '\0'); 165 166 if (loginsh && **tempv != '-') { 167 /* 168 * Mangle the argv space 169 */ 170 tempv[1][0] = '\0'; 171 tempv[1][1] = '\0'; 172 tempv[1] = NULL; 173 for (tcp = *tempv; *tcp++;) 174 continue; 175 for (tcp--; tcp >= *tempv; tcp--) 176 tcp[1] = tcp[0]; 177 *++tcp = '-'; 178 argc--; 179 } 180 if (loginsh) 181 (void) time(&chktim); 182 183 AsciiOnly = 1; 184 #ifdef NLS 185 (void) setlocale(LC_ALL, ""); 186 { 187 int k; 188 189 for (k = 0200; k <= 0377 && !Isprint(k); k++) 190 continue; 191 AsciiOnly = k > 0377; 192 } 193 #else 194 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 195 #endif /* NLS */ 196 197 /* 198 * Move the descriptors to safe places. The variable didfds is 0 while we 199 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 200 * prefer to use these. 201 */ 202 initdesc(); 203 /* 204 * XXX: This is to keep programs that use stdio happy. 205 * what we really want is freunopen() .... 206 * Closing cshin cshout and csherr (which are really stdin stdout 207 * and stderr at this point and then reopening them in the same order 208 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 209 * If that was not the case builtins like printf that use stdio 210 * would break. But in any case we could fix that with memcpy and 211 * a bit of pointer manipulation... 212 * Fortunately this is not needed under the current implementation 213 * of stdio. 214 */ 215 (void) fclose(cshin); 216 (void) fclose(cshout); 217 (void) fclose(csherr); 218 if (!(cshin = funopen((void *) &SHIN, readf, writef, seekf, closef))) 219 exit(1); 220 if (!(cshout = funopen((void *) &SHOUT, readf, writef, seekf, closef))) 221 exit(1); 222 if (!(csherr = funopen((void *) &SHERR, readf, writef, seekf, closef))) 223 exit(1); 224 (void) setvbuf(cshin, NULL, _IOLBF, 0); 225 (void) setvbuf(cshout, NULL, _IOLBF, 0); 226 (void) setvbuf(csherr, NULL, _IOLBF, 0); 227 228 /* 229 * Initialize the shell variables. ARGV and PROMPT are initialized later. 230 * STATUS is also munged in several places. CHILD is munged when 231 * forking/waiting 232 */ 233 set(STRstatus, Strsave(STR0)); 234 235 if ((tcp = getenv("HOME")) != NULL) 236 cp = quote(SAVE(tcp)); 237 else 238 cp = NULL; 239 240 if (cp == NULL) 241 fast = 1; /* No home -> can't read scripts */ 242 else 243 set(STRhome, cp); 244 dinit(cp); /* dinit thinks that HOME == cwd in a login 245 * shell */ 246 /* 247 * Grab other useful things from the environment. Should we grab 248 * everything?? 249 */ 250 if ((tcp = getenv("LOGNAME")) != NULL || 251 (tcp = getenv("USER")) != NULL) 252 set(STRuser, quote(SAVE(tcp))); 253 if ((tcp = getenv("TERM")) != NULL) 254 set(STRterm, quote(SAVE(tcp))); 255 256 /* 257 * Re-initialize path if set in environment 258 */ 259 if ((tcp = getenv("PATH")) == NULL) 260 setq(STRpath, defaultpath(), &shvhed); 261 else 262 importpath(SAVE(tcp)); 263 264 set(STRshell, Strsave(STR_SHELLPATH)); 265 266 doldol = putn((int) getpid()); /* For $$ */ 267 shtemp = Strspl(STRtmpsh, doldol); /* For << */ 268 269 /* 270 * Record the interrupt states from the parent process. If the parent is 271 * non-interruptible our hand must be forced or we (and our children) won't 272 * be either. Our children inherit termination from our parent. We catch it 273 * only if we are the login shell. 274 */ 275 /* parents interruptibility */ 276 (void) sigaction(SIGINT, NULL, &oact); 277 parintr = oact.sa_handler; 278 (void) sigaction(SIGTERM, NULL, &oact); 279 parterm = oact.sa_handler; 280 281 /* catch these all, login shell or not */ 282 (void) signal(SIGHUP, phup); /* exit processing on HUP */ 283 (void) signal(SIGXCPU, phup); /* ...and on XCPU */ 284 (void) signal(SIGXFSZ, phup); /* ...and on XFSZ */ 285 286 /* 287 * Process the arguments. 288 * 289 * Note that processing of -v/-x is actually delayed till after script 290 * processing. 291 * 292 * We set the first character of our name to be '-' if we are a shell 293 * running interruptible commands. Many programs which examine ps'es 294 * use this to filter such shells out. 295 */ 296 argc--, tempv++; 297 while (argc > 0 && (tcp = tempv[0])[0] == '-' && *++tcp != '\0' && !batch) { 298 do 299 switch (*tcp++) { 300 301 case 0: /* - Interruptible, no prompt */ 302 prompt = 0; 303 setintr = 1; 304 nofile = 1; 305 break; 306 307 case 'b': /* -b Next arg is input file */ 308 batch = 1; 309 break; 310 311 case 'c': /* -c Command input from arg */ 312 if (argc == 1) 313 xexit(0); 314 argc--, tempv++; 315 arginp = SAVE(tempv[0]); 316 prompt = 0; 317 nofile = 1; 318 break; 319 320 case 'e': /* -e Exit on any error */ 321 exiterr = 1; 322 break; 323 324 case 'f': /* -f Fast start */ 325 fast = 1; 326 break; 327 328 case 'i': /* -i Interactive, even if !intty */ 329 intact = 1; 330 nofile = 1; 331 break; 332 333 case 'm': /* -m read .cshrc (from su) */ 334 mflag = 1; 335 break; 336 337 case 'n': /* -n Don't execute */ 338 noexec = 1; 339 break; 340 341 case 'q': /* -q (Undoc'd) ... die on quit */ 342 quitit = 1; 343 break; 344 345 case 's': /* -s Read from std input */ 346 nofile = 1; 347 break; 348 349 case 't': /* -t Read one line from input */ 350 onelflg = 2; 351 prompt = 0; 352 nofile = 1; 353 break; 354 355 case 'v': /* -v Echo hist expanded input */ 356 nverbose = 1; /* ... later */ 357 break; 358 359 case 'x': /* -x Echo just before execution */ 360 nexececho = 1; /* ... later */ 361 break; 362 363 case 'V': /* -V Echo hist expanded input */ 364 setNS(STRverbose); /* NOW! */ 365 break; 366 367 case 'X': /* -X Echo just before execution */ 368 setNS(STRecho); /* NOW! */ 369 break; 370 371 } while (*tcp); 372 tempv++, argc--; 373 } 374 375 if (quitit) /* With all due haste, for debugging */ 376 (void) signal(SIGQUIT, SIG_DFL); 377 378 /* 379 * Unless prevented by -, -c, -i, -s, or -t, if there are remaining 380 * arguments the first of them is the name of a shell file from which to 381 * read commands. 382 */ 383 if (nofile == 0 && argc > 0) { 384 nofile = open(tempv[0], O_RDONLY); 385 if (nofile < 0) { 386 child = 1; /* So this doesn't return */ 387 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 388 } 389 ffile = SAVE(tempv[0]); 390 /* 391 * Replace FSHIN. Handle /dev/std{in,out,err} specially 392 * since once they are closed we cannot open them again. 393 * In that case we use our own saved descriptors 394 */ 395 if ((SHIN = dmove(nofile, FSHIN)) < 0) 396 switch(nofile) { 397 case 0: 398 SHIN = FSHIN; 399 break; 400 case 1: 401 SHIN = FSHOUT; 402 break; 403 case 2: 404 SHIN = FSHERR; 405 break; 406 default: 407 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 408 break; 409 } 410 (void) ioctl(SHIN, FIOCLEX, NULL); 411 prompt = 0; 412 /* argc not used any more */ tempv++; 413 } 414 415 intty = isatty(SHIN); 416 intty |= intact; 417 if (intty || (intact && isatty(SHOUT))) { 418 if (!batch && (uid != euid || gid != egid)) { 419 errno = EACCES; 420 child = 1; /* So this doesn't return */ 421 stderror(ERR_SYSTEM, "csh", strerror(errno)); 422 } 423 } 424 /* 425 * Decide whether we should play with signals or not. If we are explicitly 426 * told (via -i, or -) or we are a login shell (arg0 starts with -) or the 427 * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx") 428 * Note that in only the login shell is it likely that parent may have set 429 * signals to be ignored 430 */ 431 if (loginsh || intact || (intty && isatty(SHOUT))) 432 setintr = 1; 433 settell(); 434 /* 435 * Save the remaining arguments in argv. 436 */ 437 setq(STRargv, blk2short(tempv), &shvhed); 438 439 /* 440 * Set up the prompt. 441 */ 442 if (prompt) { 443 set(STRprompt, Strsave(uid == 0 ? STRsymhash : STRsymcent)); 444 /* that's a meta-questionmark */ 445 set(STRprompt2, Strsave(STRmquestion)); 446 } 447 448 /* 449 * If we are an interactive shell, then start fiddling with the signals; 450 * this is a tricky game. 451 */ 452 shpgrp = getpgrp(); 453 opgrp = tpgrp = -1; 454 if (setintr) { 455 **argv = '-'; 456 if (!quitit) /* Wary! */ 457 (void) signal(SIGQUIT, SIG_IGN); 458 (void) signal(SIGINT, pintr); 459 sigemptyset(&sigset); 460 sigaddset(&sigset, SIGINT); 461 sigprocmask(SIG_BLOCK, &sigset, NULL); 462 (void) signal(SIGTERM, SIG_IGN); 463 if (quitit == 0 && arginp == 0) { 464 (void) signal(SIGTSTP, SIG_IGN); 465 (void) signal(SIGTTIN, SIG_IGN); 466 (void) signal(SIGTTOU, SIG_IGN); 467 /* 468 * Wait till in foreground, in case someone stupidly runs csh & 469 * dont want to try to grab away the tty. 470 */ 471 if (isatty(FSHERR)) 472 f = FSHERR; 473 else if (isatty(FSHOUT)) 474 f = FSHOUT; 475 else if (isatty(OLDSTD)) 476 f = OLDSTD; 477 else 478 f = -1; 479 retry: 480 if ((tpgrp = tcgetpgrp(f)) != -1) { 481 if (tpgrp != shpgrp) { 482 sig_t old = signal(SIGTTIN, SIG_DFL); 483 (void) kill(0, SIGTTIN); 484 (void) signal(SIGTTIN, old); 485 goto retry; 486 } 487 opgrp = shpgrp; 488 shpgrp = getpid(); 489 tpgrp = shpgrp; 490 /* 491 * Setpgid will fail if we are a session leader and 492 * mypid == mypgrp (POSIX 4.3.3) 493 */ 494 if (opgrp != shpgrp) 495 if (setpgid(0, shpgrp) == -1) 496 goto notty; 497 /* 498 * We do that after we set our process group, to make sure 499 * that the process group belongs to a process in the same 500 * session as the tty (our process and our group) (POSIX 7.2.4) 501 */ 502 if (tcsetpgrp(f, shpgrp) == -1) 503 goto notty; 504 (void) ioctl(dcopy(f, FSHTTY), FIOCLEX, NULL); 505 } 506 if (tpgrp == -1) { 507 notty: 508 (void) fprintf(csherr, "Warning: no access to tty (%s).\n", 509 strerror(errno)); 510 (void) fprintf(csherr, "Thus no job control in this shell.\n"); 511 } 512 } 513 } 514 if ((setintr == 0) && (parintr == SIG_DFL)) 515 setintr = 1; 516 (void) signal(SIGCHLD, pchild); /* while signals not ready */ 517 518 /* 519 * Set an exit here in case of an interrupt or error reading the shell 520 * start-up scripts. 521 */ 522 reenter = setexit(); /* PWP */ 523 haderr = 0; /* In case second time through */ 524 if (!fast && reenter == 0) { 525 /* Will have value(STRhome) here because set fast if don't */ 526 { 527 int osetintr = setintr; 528 sig_t oparintr = parintr; 529 sigset_t osigset; 530 531 sigemptyset(&sigset); 532 sigaddset(&sigset, SIGINT); 533 sigprocmask(SIG_BLOCK, &sigset, &osigset); 534 535 setintr = 0; 536 parintr = SIG_IGN; /* Disable onintr */ 537 #ifdef _PATH_DOTCSHRC 538 (void) srcfile(_PATH_DOTCSHRC, 0, 0); 539 #endif 540 if (!fast && !arginp && !onelflg) 541 dohash(NULL, NULL); 542 #ifdef _PATH_DOTLOGIN 543 if (loginsh) 544 (void) srcfile(_PATH_DOTLOGIN, 0, 0); 545 #endif 546 sigprocmask(SIG_SETMASK, &osigset, NULL); 547 setintr = osetintr; 548 parintr = oparintr; 549 } 550 (void) srccat(value(STRhome), STRsldotcshrc); 551 552 if (!fast && !arginp && !onelflg && !havhash) 553 dohash(NULL, NULL); 554 /* 555 * Source history before .login so that it is available in .login 556 */ 557 if ((cp = value(STRhistfile)) != STRNULL) 558 loadhist[2] = cp; 559 dosource(loadhist, NULL); 560 if (loginsh) 561 (void) srccat(value(STRhome), STRsldotlogin); 562 } 563 564 /* 565 * Now are ready for the -v and -x flags 566 */ 567 if (nverbose) 568 setNS(STRverbose); 569 if (nexececho) 570 setNS(STRecho); 571 572 /* 573 * All the rest of the world is inside this call. The argument to process 574 * indicates whether it should catch "error unwinds". Thus if we are a 575 * interactive shell our call here will never return by being blown past on 576 * an error. 577 */ 578 process(setintr); 579 580 /* 581 * Mop-up. 582 */ 583 if (intty) { 584 if (loginsh) { 585 (void) fprintf(cshout, "logout\n"); 586 (void) close(SHIN); 587 child = 1; 588 goodbye(); 589 } 590 else { 591 (void) fprintf(cshout, "exit\n"); 592 } 593 } 594 rechist(); 595 exitstat(); 596 return (0); 597 } 598 599 void 600 untty() 601 { 602 if (tpgrp > 0) { 603 (void) setpgid(0, opgrp); 604 (void) tcsetpgrp(FSHTTY, opgrp); 605 } 606 } 607 608 void 609 importpath(cp) 610 Char *cp; 611 { 612 int i = 0; 613 Char *dp; 614 Char **pv; 615 int c; 616 617 for (dp = cp; *dp; dp++) 618 if (*dp == ':') 619 i++; 620 /* 621 * i+2 where i is the number of colons in the path. There are i+1 622 * directories in the path plus we need room for a zero terminator. 623 */ 624 pv = (Char **) xcalloc((size_t) (i + 2), sizeof(Char **)); 625 dp = cp; 626 i = 0; 627 if (*dp) 628 for (;;) { 629 if ((c = *dp) == ':' || c == 0) { 630 *dp = 0; 631 pv[i++] = Strsave(*cp ? cp : STRdot); 632 if (c) { 633 cp = dp + 1; 634 *dp = ':'; 635 } 636 else 637 break; 638 } 639 dp++; 640 } 641 pv[i] = 0; 642 set1(STRpath, pv, &shvhed); 643 } 644 645 /* 646 * Source to the file which is the catenation of the argument names. 647 */ 648 static int 649 srccat(cp, dp) 650 Char *cp, *dp; 651 { 652 Char *ep = Strspl(cp, dp); 653 char *ptr = short2str(ep); 654 655 xfree((ptr_t) ep); 656 return srcfile(ptr, mflag ? 0 : 1, 0); 657 } 658 659 /* 660 * Source to a file putting the file descriptor in a safe place (> 2). 661 */ 662 static int 663 srcfile(f, onlyown, flag) 664 char *f; 665 bool onlyown, flag; 666 { 667 int unit; 668 669 if ((unit = open(f, O_RDONLY)) == -1) 670 return 0; 671 unit = dmove(unit, -1); 672 673 (void) ioctl(unit, FIOCLEX, NULL); 674 srcunit(unit, onlyown, flag); 675 return 1; 676 } 677 678 /* 679 * Source to a unit. If onlyown it must be our file or our group or 680 * we don't chance it. This occurs on ".cshrc"s and the like. 681 */ 682 int insource; 683 static void 684 srcunit(unit, onlyown, hflg) 685 int unit; 686 bool onlyown, hflg; 687 { 688 /* We have to push down a lot of state here */ 689 /* All this could go into a structure */ 690 int oSHIN = -1, oldintty = intty, oinsource = insource; 691 struct whyle *oldwhyl = whyles; 692 Char *ogointr = gointr, *oarginp = arginp; 693 Char *oevalp = evalp, **oevalvec = evalvec; 694 int oonelflg = onelflg; 695 bool oenterhist = enterhist; 696 char OHIST = HIST; 697 bool otell = cantell; 698 699 struct Bin saveB; 700 sigset_t sigset, osigset; 701 jmp_buf oldexit; 702 703 /* The (few) real local variables */ 704 int my_reenter; 705 706 if (unit < 0) 707 return; 708 if (didfds) 709 donefds(); 710 if (onlyown) { 711 struct stat stb; 712 713 if (fstat(unit, &stb) < 0) { 714 (void) close(unit); 715 return; 716 } 717 } 718 719 /* 720 * There is a critical section here while we are pushing down the input 721 * stream since we have stuff in different structures. If we weren't 722 * careful an interrupt could corrupt SHIN's Bin structure and kill the 723 * shell. 724 * 725 * We could avoid the critical region by grouping all the stuff in a single 726 * structure and pointing at it to move it all at once. This is less 727 * efficient globally on many variable references however. 728 */ 729 insource = 1; 730 getexit(oldexit); 731 732 if (setintr) { 733 sigemptyset(&sigset); 734 sigaddset(&sigset, SIGINT); 735 sigprocmask(SIG_BLOCK, &sigset, &osigset); 736 } 737 /* Setup the new values of the state stuff saved above */ 738 memcpy(&saveB, &B, sizeof(B)); 739 fbuf = NULL; 740 fseekp = feobp = fblocks = 0; 741 oSHIN = SHIN, SHIN = unit, arginp = 0, onelflg = 0; 742 intty = isatty(SHIN), whyles = 0, gointr = 0; 743 evalvec = 0; 744 evalp = 0; 745 enterhist = hflg; 746 if (enterhist) 747 HIST = '\0'; 748 749 /* 750 * Now if we are allowing commands to be interrupted, we let ourselves be 751 * interrupted. 752 */ 753 if (setintr) 754 sigprocmask(SIG_SETMASK, &osigset, NULL); 755 settell(); 756 757 if ((my_reenter = setexit()) == 0) 758 process(0); /* 0 -> blow away on errors */ 759 760 if (setintr) 761 sigprocmask(SIG_SETMASK, &osigset, NULL); 762 if (oSHIN >= 0) { 763 int i; 764 765 /* We made it to the new state... free up its storage */ 766 /* This code could get run twice but xfree doesn't care */ 767 for (i = 0; i < fblocks; i++) 768 xfree((ptr_t) fbuf[i]); 769 xfree((ptr_t) fbuf); 770 771 /* Reset input arena */ 772 memcpy(&B, &saveB, sizeof(B)); 773 774 (void) close(SHIN), SHIN = oSHIN; 775 arginp = oarginp, onelflg = oonelflg; 776 evalp = oevalp, evalvec = oevalvec; 777 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 778 if (enterhist) 779 HIST = OHIST; 780 enterhist = oenterhist; 781 cantell = otell; 782 } 783 784 resexit(oldexit); 785 /* 786 * If process reset() (effectively an unwind) then we must also unwind. 787 */ 788 if (my_reenter) 789 stderror(ERR_SILENT); 790 insource = oinsource; 791 } 792 793 void 794 rechist() 795 { 796 Char buf[BUFSIZ], hbuf[BUFSIZ], *hfile; 797 int fp, ftmp, oldidfds; 798 struct varent *shist; 799 800 if (!fast) { 801 /* 802 * If $savehist is just set, we use the value of $history 803 * else we use the value in $savehist 804 */ 805 if ((shist = adrof(STRsavehist)) != NULL) { 806 if (shist->vec[0][0] != '\0') 807 (void) Strcpy(hbuf, shist->vec[0]); 808 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 809 (void) Strcpy(hbuf, shist->vec[0]); 810 else 811 return; 812 } 813 else 814 return; 815 816 if ((hfile = value(STRhistfile)) == STRNULL) { 817 hfile = Strcpy(buf, value(STRhome)); 818 (void) Strcat(buf, STRsldthist); 819 } 820 821 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 822 0600)) == -1) 823 return; 824 825 oldidfds = didfds; 826 didfds = 0; 827 ftmp = SHOUT; 828 SHOUT = fp; 829 dumphist[2] = hbuf; 830 dohist(dumphist, NULL); 831 SHOUT = ftmp; 832 (void) close(fp); 833 didfds = oldidfds; 834 } 835 } 836 837 void 838 goodbye() 839 { 840 rechist(); 841 842 if (loginsh) { 843 (void) signal(SIGQUIT, SIG_IGN); 844 (void) signal(SIGINT, SIG_IGN); 845 (void) signal(SIGTERM, SIG_IGN); 846 setintr = 0; /* No interrupts after "logout" */ 847 if (!(adrof(STRlogout))) 848 set(STRlogout, STRnormal); 849 #ifdef _PATH_DOTLOGOUT 850 (void) srcfile(_PATH_DOTLOGOUT, 0, 0); 851 #endif 852 if (adrof(STRhome)) 853 (void) srccat(value(STRhome), STRsldtlogout); 854 } 855 exitstat(); 856 } 857 858 void 859 exitstat() 860 { 861 Char *s; 862 #ifdef PROF 863 monitor(0); 864 #endif 865 /* 866 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 867 * directly because we poke child here. Otherwise we might continue 868 * unwarrantedly (sic). 869 */ 870 child = 1; 871 s = value(STRstatus); 872 xexit(s ? getn(s) : 0); 873 } 874 875 /* 876 * in the event of a HUP we want to save the history 877 */ 878 static void 879 phup(sig) 880 int sig; 881 { 882 rechist(); 883 884 /* 885 * We kill the last foreground process group. It then becomes 886 * responsible to propagate the SIGHUP to its progeny. 887 */ 888 { 889 struct process *pp, *np; 890 891 for (pp = proclist.p_next; pp; pp = pp->p_next) { 892 np = pp; 893 /* 894 * Find if this job is in the foreground. It could be that 895 * the process leader has exited and the foreground flag 896 * is cleared for it. 897 */ 898 do 899 /* 900 * If a process is in the foreground; we try to kill 901 * it's process group. If we succeed, then the 902 * whole job is gone. Otherwise we keep going... 903 * But avoid sending HUP to the shell again. 904 */ 905 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 906 kill(-np->p_jobid, SIGHUP) != -1) { 907 /* In case the job was suspended... */ 908 (void) kill(-np->p_jobid, SIGCONT); 909 break; 910 } 911 while ((np = np->p_friends) != pp); 912 } 913 } 914 xexit(sig); 915 } 916 917 Char *jobargv[2] = {STRjobs, 0}; 918 919 /* 920 * Catch an interrupt, e.g. during lexical input. 921 * If we are an interactive shell, we reset the interrupt catch 922 * immediately. In any case we drain the shell output, 923 * and finally go through the normal error mechanism, which 924 * gets a chance to make the shell go away. 925 */ 926 /* ARGSUSED */ 927 void 928 pintr(notused) 929 int notused; 930 { 931 pintr1(1); 932 } 933 934 void 935 pintr1(wantnl) 936 bool wantnl; 937 { 938 Char **v; 939 sigset_t sigset, osigset; 940 941 sigemptyset(&sigset); 942 sigprocmask(SIG_BLOCK, &sigset, &osigset); 943 if (setintr) { 944 sigset = osigset; 945 sigdelset(&sigset, SIGINT); 946 sigprocmask(SIG_SETMASK, &sigset, NULL); 947 if (pjobs) { 948 pjobs = 0; 949 (void) fprintf(cshout, "\n"); 950 dojobs(jobargv, NULL); 951 stderror(ERR_NAME | ERR_INTR); 952 } 953 } 954 sigdelset(&osigset, SIGCHLD); 955 sigprocmask(SIG_SETMASK, &osigset, NULL); 956 (void) fpurge(cshout); 957 (void) endpwent(); 958 959 /* 960 * If we have an active "onintr" then we search for the label. Note that if 961 * one does "onintr -" then we shan't be interruptible so we needn't worry 962 * about that here. 963 */ 964 if (gointr) { 965 gotolab(gointr); 966 timflg = 0; 967 if ((v = pargv) != NULL) 968 pargv = 0, blkfree(v); 969 if ((v = gargv) != NULL) 970 gargv = 0, blkfree(v); 971 reset(); 972 } 973 else if (intty && wantnl) { 974 (void) fputc('\r', cshout); 975 (void) fputc('\n', cshout); 976 } 977 stderror(ERR_SILENT); 978 } 979 980 /* 981 * Process is the main driving routine for the shell. 982 * It runs all command processing, except for those within { ... } 983 * in expressions (which is run by a routine evalav in sh.exp.c which 984 * is a stripped down process), and `...` evaluation which is run 985 * also by a subset of this code in sh.glob.c in the routine backeval. 986 * 987 * The code here is a little strange because part of it is interruptible 988 * and hence freeing of structures appears to occur when none is necessary 989 * if this is ignored. 990 * 991 * Note that if catch is not set then we will unwind on any error. 992 * If an end-of-file occurs, we return. 993 */ 994 static struct command *savet = NULL; 995 void 996 process(catch) 997 bool catch; 998 { 999 jmp_buf osetexit; 1000 struct command *t = savet; 1001 sigset_t sigset; 1002 1003 savet = NULL; 1004 getexit(osetexit); 1005 for (;;) { 1006 pendjob(); 1007 paraml.next = paraml.prev = ¶ml; 1008 paraml.word = STRNULL; 1009 (void) setexit(); 1010 justpr = enterhist; /* execute if not entering history */ 1011 1012 /* 1013 * Interruptible during interactive reads 1014 */ 1015 if (setintr) { 1016 sigemptyset(&sigset); 1017 sigaddset(&sigset, SIGINT); 1018 sigprocmask(SIG_UNBLOCK, &sigset, NULL); 1019 } 1020 1021 /* 1022 * For the sake of reset() 1023 */ 1024 freelex(¶ml); 1025 if (savet) 1026 freesyn(savet), savet = NULL; 1027 1028 if (haderr) { 1029 if (!catch) { 1030 /* unwind */ 1031 doneinp = 0; 1032 resexit(osetexit); 1033 savet = t; 1034 reset(); 1035 } 1036 haderr = 0; 1037 /* 1038 * Every error is eventually caught here or the shell dies. It is 1039 * at this point that we clean up any left-over open files, by 1040 * closing all but a fixed number of pre-defined files. Thus 1041 * routines don't have to worry about leaving files open due to 1042 * deeper errors... they will get closed here. 1043 */ 1044 closem(); 1045 continue; 1046 } 1047 if (doneinp) { 1048 doneinp = 0; 1049 break; 1050 } 1051 if (chkstop) 1052 chkstop--; 1053 if (neednote) 1054 pnote(); 1055 if (intty && prompt && evalvec == 0) { 1056 mailchk(); 1057 /* 1058 * If we are at the end of the input buffer then we are going to 1059 * read fresh stuff. Otherwise, we are rereading input and don't 1060 * need or want to prompt. 1061 */ 1062 if (aret == F_SEEK && fseekp == feobp) 1063 printprompt(); 1064 (void) fflush(cshout); 1065 } 1066 if (seterr) { 1067 xfree((ptr_t) seterr); 1068 seterr = NULL; 1069 } 1070 1071 /* 1072 * Echo not only on VERBOSE, but also with history expansion. If there 1073 * is a lexical error then we forego history echo. 1074 */ 1075 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1076 prlex(csherr, ¶ml); 1077 } 1078 1079 /* 1080 * The parser may lose space if interrupted. 1081 */ 1082 if (setintr) 1083 sigprocmask(SIG_BLOCK, &sigset, NULL); 1084 1085 /* 1086 * Save input text on the history list if reading in old history, or it 1087 * is from the terminal at the top level and not in a loop. 1088 * 1089 * PWP: entry of items in the history list while in a while loop is done 1090 * elsewhere... 1091 */ 1092 if (enterhist || (catch && intty && !whyles)) 1093 savehist(¶ml); 1094 1095 /* 1096 * Print lexical error messages, except when sourcing history lists. 1097 */ 1098 if (!enterhist && seterr) 1099 stderror(ERR_OLD); 1100 1101 /* 1102 * If had a history command :p modifier then this is as far as we 1103 * should go 1104 */ 1105 if (justpr) 1106 reset(); 1107 1108 alias(¶ml); 1109 1110 /* 1111 * Parse the words of the input into a parse tree. 1112 */ 1113 savet = syntax(paraml.next, ¶ml, 0); 1114 if (seterr) 1115 stderror(ERR_OLD); 1116 1117 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1118 1119 /* 1120 * Made it! 1121 */ 1122 freelex(¶ml); 1123 freesyn((struct command *) savet), savet = NULL; 1124 } 1125 resexit(osetexit); 1126 savet = t; 1127 } 1128 1129 void 1130 /*ARGSUSED*/ 1131 dosource(v, t) 1132 Char **v; 1133 struct command *t; 1134 1135 { 1136 Char *f; 1137 bool hflg = 0; 1138 Char buf[BUFSIZ]; 1139 1140 v++; 1141 if (*v && eq(*v, STRmh)) { 1142 if (*++v == NULL) 1143 stderror(ERR_NAME | ERR_HFLAG); 1144 hflg++; 1145 } 1146 (void) Strcpy(buf, *v); 1147 f = globone(buf, G_ERROR); 1148 (void) strcpy((char *) buf, short2str(f)); 1149 xfree((ptr_t) f); 1150 if (!srcfile((char *) buf, 0, hflg) && !hflg) 1151 stderror(ERR_SYSTEM, (char *) buf, strerror(errno)); 1152 } 1153 1154 /* 1155 * Check for mail. 1156 * If we are a login shell, then we don't want to tell 1157 * about any mail file unless its been modified 1158 * after the time we started. 1159 * This prevents us from telling the user things he already 1160 * knows, since the login program insists on saying 1161 * "You have mail." 1162 */ 1163 static void 1164 mailchk() 1165 { 1166 struct varent *v; 1167 Char **vp; 1168 time_t t; 1169 int intvl, cnt; 1170 struct stat stb; 1171 bool new; 1172 1173 v = adrof(STRmail); 1174 if (v == 0) 1175 return; 1176 (void) time(&t); 1177 vp = v->vec; 1178 cnt = blklen(vp); 1179 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1180 if (intvl < 1) 1181 intvl = 1; 1182 if (chktim + intvl > t) 1183 return; 1184 for (; *vp; vp++) { 1185 if (stat(short2str(*vp), &stb) < 0) 1186 continue; 1187 new = stb.st_mtime > time0.tv_sec; 1188 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1189 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1190 (loginsh && !new)) 1191 continue; 1192 if (cnt == 1) 1193 (void) fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1194 else 1195 (void) fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1196 vis_str(*vp)); 1197 } 1198 chktim = t; 1199 } 1200 1201 /* 1202 * Extract a home directory from the password file 1203 * The argument points to a buffer where the name of the 1204 * user whose home directory is sought is currently. 1205 * We write the home directory of the user back there. 1206 */ 1207 int 1208 gethdir(home) 1209 Char *home; 1210 { 1211 Char *h; 1212 struct passwd *pw; 1213 1214 /* 1215 * Is it us? 1216 */ 1217 if (*home == '\0') { 1218 if ((h = value(STRhome)) != NULL) { 1219 (void) Strcpy(home, h); 1220 return 0; 1221 } 1222 else 1223 return 1; 1224 } 1225 1226 if ((pw = getpwnam(short2str(home))) != NULL) { 1227 (void) Strcpy(home, str2short(pw->pw_dir)); 1228 return 0; 1229 } 1230 else 1231 return 1; 1232 } 1233 1234 /* 1235 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1236 * We also check if the shell has already changed the decriptor to point to 1237 * 0, 1, 2 when didfds is set. 1238 */ 1239 #define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1240 1241 static int 1242 readf(oreo, buf, siz) 1243 void *oreo; 1244 char *buf; 1245 int siz; 1246 { 1247 return read(DESC(oreo), buf, siz); 1248 } 1249 1250 1251 static int 1252 writef(oreo, buf, siz) 1253 void *oreo; 1254 const char *buf; 1255 int siz; 1256 { 1257 return write(DESC(oreo), buf, siz); 1258 } 1259 1260 static fpos_t 1261 seekf(oreo, off, whence) 1262 void *oreo; 1263 fpos_t off; 1264 int whence; 1265 { 1266 return lseek(DESC(oreo), off, whence); 1267 } 1268 1269 1270 static int 1271 closef(oreo) 1272 void *oreo; 1273 { 1274 return close(DESC(oreo)); 1275 } 1276 1277 1278 /* 1279 * Print the visible version of a string. 1280 */ 1281 int 1282 vis_fputc(ch, fp) 1283 int ch; 1284 FILE *fp; 1285 { 1286 char uenc[5]; /* 4 + NULL */ 1287 1288 if (ch & QUOTE) 1289 return fputc(ch & TRIM, fp); 1290 /* 1291 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1292 * be encoded, but currently there is no way in vis to do that. 1293 */ 1294 (void) vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1295 return fputs(uenc, fp); 1296 } 1297 1298 /* 1299 * Move the initial descriptors to their eventual 1300 * resting places, closin all other units. 1301 */ 1302 void 1303 initdesc() 1304 { 1305 1306 didfds = 0; /* 0, 1, 2 aren't set up */ 1307 (void) ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1308 (void) ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1309 (void) ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1310 (void) ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1311 closem(); 1312 } 1313 1314 1315 void 1316 #ifdef PROF 1317 done(i) 1318 #else 1319 xexit(i) 1320 #endif 1321 int i; 1322 { 1323 untty(); 1324 _exit(i); 1325 } 1326 1327 static Char ** 1328 defaultpath() 1329 { 1330 char *ptr; 1331 Char **blk, **blkp; 1332 struct stat stb; 1333 1334 blkp = blk = (Char **) xmalloc((size_t) sizeof(Char *) * 10); 1335 1336 #define DIRAPPEND(a) \ 1337 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1338 *blkp++ = SAVE(ptr) 1339 1340 DIRAPPEND(_PATH_BIN); 1341 DIRAPPEND(_PATH_USRBIN); 1342 1343 #undef DIRAPPEND 1344 1345 #if 0 1346 if (euid != 0 && uid != 0) 1347 *blkp++ = Strsave(STRdot); 1348 #endif 1349 1350 *blkp = NULL; 1351 return (blk); 1352 } 1353 1354 void 1355 printprompt() 1356 { 1357 Char *cp; 1358 1359 if (!whyles) { 1360 for (cp = value(STRprompt); *cp; cp++) 1361 if (*cp == HIST) 1362 (void) fprintf(cshout, "%d", eventno + 1); 1363 else { 1364 if (*cp == '\\' && cp[1] == HIST) 1365 cp++; 1366 (void) vis_fputc(*cp | QUOTE, cshout); 1367 } 1368 } 1369 else 1370 /* 1371 * Prompt for forward reading loop body content. 1372 */ 1373 (void) fprintf(cshout, "? "); 1374 (void) fflush(cshout); 1375 } 1376