1 /* $NetBSD: csh.c,v 1.45 2013/01/23 16:39:03 christos 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1980, 1991, 1993\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)csh.c 8.2 (Berkeley) 10/12/93"; 41 #else 42 __RCSID("$NetBSD: csh.c,v 1.45 2013/01/23 16:39:03 christos Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #include <sys/types.h> 47 #include <sys/ioctl.h> 48 #include <sys/stat.h> 49 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <locale.h> 53 #include <paths.h> /* should this be included in pathnames.h instead? */ 54 #include <pwd.h> 55 #include <stdarg.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <time.h> 59 #include <unistd.h> 60 #include <vis.h> 61 62 #include "csh.h" 63 #include "extern.h" 64 #include "pathnames.h" 65 #include "proc.h" 66 67 /* 68 * C Shell 69 * 70 * Bill Joy, UC Berkeley, California, USA 71 * October 1978, May 1980 72 * 73 * Jim Kulp, IIASA, Laxenburg, Austria 74 * April 1980 75 * 76 * Christos Zoulas, Cornell University 77 * June, 1991 78 */ 79 80 Char *dumphist[] = {STRhistory, STRmh, 0, 0}; 81 Char *tildehist[] = {STRsource, STRmh, STRtildothist, 0}; 82 83 int nofile = 0; 84 int batch = 0; 85 int enterhist = 0; 86 int fast = 0; 87 int mflag = 0; 88 int nexececho = 0; 89 int nverbose = 0; 90 int prompt = 1; 91 int quitit = 0; 92 int reenter = 0; 93 94 extern char **environ; 95 96 static int readf(void *, char *, int); 97 static off_t seekf(void *, off_t, int); 98 static int writef(void *, const char *, int); 99 static int closef(void *); 100 static int srccat(Char *, Char *); 101 static int srcfile(const char *, int, int); 102 __dead static void phup(int); 103 static void srcunit(int, int, int); 104 static void mailchk(void); 105 #ifndef _PATH_DEFPATH 106 static Char **defaultpath(void); 107 #endif 108 #ifdef EDITING 109 int editing = 0; 110 #endif 111 112 int 113 main(int argc, char *argv[]) 114 { 115 struct sigaction oact; 116 Char *cp; 117 char *tcp, **tempv; 118 const char *ecp; 119 sigset_t nsigset; 120 int f; 121 122 cshin = stdin; 123 cshout = stdout; 124 csherr = stderr; 125 126 setprogname(argv[0]); 127 settimes(); /* Immed. estab. timing base */ 128 129 /* 130 * Initialize non constant strings 131 */ 132 #ifdef _PATH_BSHELL 133 STR_BSHELL = SAVE(_PATH_BSHELL); 134 #endif 135 #ifdef _PATH_CSHELL 136 STR_SHELLPATH = SAVE(_PATH_CSHELL); 137 #endif 138 STR_environ = blk2short(environ); 139 environ = short2blk(STR_environ); /* So that we can free it */ 140 STR_WORD_CHARS = SAVE(WORD_CHARS); 141 142 HIST = '!'; 143 HISTSUB = '^'; 144 word_chars = STR_WORD_CHARS; 145 146 tempv = argv; 147 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 148 quitit = 1; 149 uid = getuid(); 150 gid = getgid(); 151 euid = geteuid(); 152 egid = getegid(); 153 /* 154 * We are a login shell if: 1. we were invoked as -<something> and we had 155 * no arguments 2. or we were invoked only with the -l flag 156 */ 157 loginsh = (**tempv == '-' && argc == 1) || 158 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 159 tempv[1][2] == '\0'); 160 161 if (loginsh && **tempv != '-') { 162 /* 163 * Mangle the argv space 164 */ 165 tempv[1][0] = '\0'; 166 tempv[1][1] = '\0'; 167 tempv[1] = NULL; 168 for (tcp = *tempv; *tcp++;) 169 continue; 170 for (tcp--; tcp >= *tempv; tcp--) 171 tcp[1] = tcp[0]; 172 *++tcp = '-'; 173 argc--; 174 } 175 if (loginsh) 176 (void)time(&chktim); 177 178 AsciiOnly = 1; 179 #ifdef NLS 180 (void)setlocale(LC_ALL, ""); 181 { 182 int k; 183 184 for (k = 0200; k <= 0377 && !Isprint(k); k++) 185 continue; 186 AsciiOnly = k > 0377; 187 } 188 #else 189 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 190 #endif /* NLS */ 191 192 /* 193 * Move the descriptors to safe places. The variable didfds is 0 while we 194 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 195 * prefer to use these. 196 */ 197 initdesc(); 198 /* 199 * XXX: This is to keep programs that use stdio happy. 200 * what we really want is freunopen() .... 201 * Closing cshin cshout and csherr (which are really stdin stdout 202 * and stderr at this point and then reopening them in the same order 203 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 204 * If that was not the case builtins like printf that use stdio 205 * would break. But in any case we could fix that with memcpy and 206 * a bit of pointer manipulation... 207 * Fortunately this is not needed under the current implementation 208 * of stdio. 209 */ 210 (void)fclose(cshin); 211 (void)fclose(cshout); 212 (void)fclose(csherr); 213 if (!(cshin = funopen((void *) &SHIN, readf, writef, seekf, closef))) 214 exit(1); 215 if (!(cshout = funopen((void *) &SHOUT, readf, writef, seekf, closef))) 216 exit(1); 217 if (!(csherr = funopen((void *) &SHERR, readf, writef, seekf, closef))) 218 exit(1); 219 (void)setvbuf(cshin, NULL, _IOLBF, 0); 220 (void)setvbuf(cshout, NULL, _IOLBF, 0); 221 (void)setvbuf(csherr, NULL, _IOLBF, 0); 222 223 /* 224 * Initialize the shell variables. ARGV and PROMPT are initialized later. 225 * STATUS is also munged in several places. CHILD is munged when 226 * forking/waiting 227 */ 228 set(STRstatus, Strsave(STR0)); 229 230 if ((ecp = getenv("HOME")) != NULL) 231 cp = quote(SAVE(ecp)); 232 else 233 cp = NULL; 234 235 if (cp == NULL) 236 fast = 1; /* No home -> can't read scripts */ 237 else 238 set(STRhome, cp); 239 dinit(cp); /* dinit thinks that HOME == cwd in a login 240 * shell */ 241 /* 242 * Grab other useful things from the environment. Should we grab 243 * everything?? 244 */ 245 if ((ecp = getenv("LOGNAME")) != NULL || 246 (ecp = getenv("USER")) != NULL) 247 set(STRuser, quote(SAVE(ecp))); 248 if ((ecp = getenv("TERM")) != NULL) 249 set(STRterm, quote(SAVE(ecp))); 250 251 /* 252 * Re-initialize path if set in environment 253 */ 254 if ((ecp = getenv("PATH")) == NULL) { 255 #ifdef _PATH_DEFPATH 256 importpath(str2short(_PATH_DEFPATH)); 257 #else 258 setq(STRpath, defaultpath(), &shvhed); 259 #endif 260 } else { 261 importpath(str2short(ecp)); 262 } 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 case 0: /* - Interruptible, no prompt */ 301 prompt = 0; 302 setintr = 1; 303 nofile = 1; 304 break; 305 case 'b': /* -b Next arg is input file */ 306 batch = 1; 307 break; 308 case 'c': /* -c Command input from arg */ 309 if (argc == 1) 310 xexit(0); 311 argc--, tempv++; 312 arginp = SAVE(tempv[0]); 313 prompt = 0; 314 nofile = 1; 315 break; 316 case 'e': /* -e Exit on any error */ 317 exiterr = 1; 318 break; 319 case 'f': /* -f Fast start */ 320 fast = 1; 321 break; 322 case 'i': /* -i Interactive, even if !intty */ 323 intact = 1; 324 nofile = 1; 325 break; 326 case 'm': /* -m read .cshrc (from su) */ 327 mflag = 1; 328 break; 329 case 'n': /* -n Don't execute */ 330 noexec = 1; 331 break; 332 case 'q': /* -q (Undoc'd) ... die on quit */ 333 quitit = 1; 334 break; 335 case 's': /* -s Read from std input */ 336 nofile = 1; 337 break; 338 case 't': /* -t Read one line from input */ 339 onelflg = 2; 340 prompt = 0; 341 nofile = 1; 342 break; 343 case 'v': /* -v Echo hist expanded input */ 344 nverbose = 1; /* ... later */ 345 break; 346 case 'x': /* -x Echo just before execution */ 347 nexececho = 1; /* ... later */ 348 break; 349 case 'V': /* -V Echo hist expanded input */ 350 setNS(STRverbose); /* NOW! */ 351 break; 352 case 'X': /* -X Echo just before execution */ 353 setNS(STRecho); /* NOW! */ 354 break; 355 356 } while (*tcp); 357 tempv++, argc--; 358 } 359 360 if (quitit) /* With all due haste, for debugging */ 361 (void)signal(SIGQUIT, SIG_DFL); 362 363 /* 364 * Unless prevented by -, -c, -i, -s, or -t, if there are remaining 365 * arguments the first of them is the name of a shell file from which to 366 * read commands. 367 */ 368 if (nofile == 0 && argc > 0) { 369 nofile = open(tempv[0], O_RDONLY); 370 if (nofile < 0) { 371 child = 1; /* So this doesn't return */ 372 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 373 } 374 ffile = SAVE(tempv[0]); 375 /* 376 * Replace FSHIN. Handle /dev/std{in,out,err} specially 377 * since once they are closed we cannot open them again. 378 * In that case we use our own saved descriptors 379 */ 380 if ((SHIN = dmove(nofile, FSHIN)) < 0) 381 switch(nofile) { 382 case 0: 383 SHIN = FSHIN; 384 break; 385 case 1: 386 SHIN = FSHOUT; 387 break; 388 case 2: 389 SHIN = FSHERR; 390 break; 391 default: 392 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 393 /* NOTREACHED */ 394 } 395 (void)ioctl(SHIN, FIOCLEX, NULL); 396 prompt = 0; 397 /* argc not used any more */ tempv++; 398 } 399 400 intty = isatty(SHIN); 401 intty |= intact; 402 if (intty || (intact && isatty(SHOUT))) { 403 if (!batch && (uid != euid || gid != egid)) { 404 errno = EACCES; 405 child = 1; /* So this doesn't return */ 406 stderror(ERR_SYSTEM, "csh", strerror(errno)); 407 } 408 } 409 /* 410 * Decide whether we should play with signals or not. If we are explicitly 411 * told (via -i, or -) or we are a login shell (arg0 starts with -) or the 412 * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx") 413 * Note that in only the login shell is it likely that parent may have set 414 * signals to be ignored 415 */ 416 if (loginsh || intact || (intty && isatty(SHOUT))) 417 setintr = 1; 418 settell(); 419 /* 420 * Save the remaining arguments in argv. 421 */ 422 setq(STRargv, blk2short(tempv), &shvhed); 423 424 /* 425 * Set up the prompt. 426 */ 427 if (prompt) { 428 set(STRprompt, Strsave(uid == 0 ? STRsymhash : STRsymcent)); 429 /* that's a meta-questionmark */ 430 set(STRprompt2, Strsave(STRmquestion)); 431 } 432 433 /* 434 * If we are an interactive shell, then start fiddling with the signals; 435 * this is a tricky game. 436 */ 437 shpgrp = getpgrp(); 438 opgrp = tpgrp = -1; 439 if (setintr) { 440 **argv = '-'; 441 if (!quitit) /* Wary! */ 442 (void)signal(SIGQUIT, SIG_IGN); 443 (void)signal(SIGINT, pintr); 444 sigemptyset(&nsigset); 445 (void)sigaddset(&nsigset, SIGINT); 446 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 447 (void)signal(SIGTERM, SIG_IGN); 448 if (quitit == 0 && arginp == 0) { 449 (void)signal(SIGTSTP, SIG_IGN); 450 (void)signal(SIGTTIN, SIG_IGN); 451 (void)signal(SIGTTOU, SIG_IGN); 452 /* 453 * Wait till in foreground, in case someone stupidly runs csh & 454 * dont want to try to grab away the tty. 455 */ 456 if (isatty(FSHERR)) 457 f = FSHERR; 458 else if (isatty(FSHOUT)) 459 f = FSHOUT; 460 else if (isatty(OLDSTD)) 461 f = OLDSTD; 462 else 463 f = -1; 464 retry: 465 if ((tpgrp = tcgetpgrp(f)) != -1) { 466 if (tpgrp != shpgrp) { 467 sig_t old = signal(SIGTTIN, SIG_DFL); 468 (void)kill(0, SIGTTIN); 469 (void)signal(SIGTTIN, old); 470 goto retry; 471 } 472 opgrp = shpgrp; 473 shpgrp = getpid(); 474 tpgrp = shpgrp; 475 /* 476 * Setpgid will fail if we are a session leader and 477 * mypid == mypgrp (POSIX 4.3.3) 478 */ 479 if (opgrp != shpgrp) 480 if (setpgid(0, shpgrp) == -1) 481 goto notty; 482 /* 483 * We do that after we set our process group, to make sure 484 * that the process group belongs to a process in the same 485 * session as the tty (our process and our group) (POSIX 7.2.4) 486 */ 487 if (tcsetpgrp(f, shpgrp) == -1) 488 goto notty; 489 (void)ioctl(dcopy(f, FSHTTY), FIOCLEX, NULL); 490 } 491 if (tpgrp == -1) { 492 notty: 493 (void)fprintf(csherr, "Warning: no access to tty (%s).\n", 494 strerror(errno)); 495 (void)fprintf(csherr, "Thus no job control in this shell.\n"); 496 } 497 } 498 } 499 if ((setintr == 0) && (parintr == SIG_DFL)) 500 setintr = 1; 501 (void)signal(SIGCHLD, pchild); /* while signals not ready */ 502 503 /* 504 * Set an exit here in case of an interrupt or error reading the shell 505 * start-up scripts. 506 */ 507 reenter = setexit(); /* PWP */ 508 haderr = 0; /* In case second time through */ 509 if (!fast && reenter == 0) { 510 /* Will have value(STRhome) here because set fast if don't */ 511 { 512 sig_t oparintr; 513 sigset_t osigset; 514 int osetintr; 515 516 oparintr = parintr; 517 osetintr = setintr; 518 sigemptyset(&nsigset); 519 (void)sigaddset(&nsigset, SIGINT); 520 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 521 522 setintr = 0; 523 parintr = SIG_IGN; /* Disable onintr */ 524 #ifdef _PATH_DOTCSHRC 525 (void)srcfile(_PATH_DOTCSHRC, 0, 0); 526 #endif 527 if (!fast && !arginp && !onelflg) 528 dohash(NULL, NULL); 529 #ifdef _PATH_DOTLOGIN 530 if (loginsh) 531 (void)srcfile(_PATH_DOTLOGIN, 0, 0); 532 #endif 533 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 534 setintr = osetintr; 535 parintr = oparintr; 536 } 537 (void)srccat(value(STRhome), STRsldotcshrc); 538 539 if (!fast && !arginp && !onelflg && !havhash) 540 dohash(NULL, NULL); 541 /* 542 * Source history before .login so that it is available in .login 543 */ 544 if ((cp = value(STRhistfile)) != STRNULL) 545 tildehist[2] = cp; 546 dosource(tildehist, NULL); 547 if (loginsh) 548 (void)srccat(value(STRhome), STRsldotlogin); 549 } 550 551 /* 552 * Now are ready for the -v and -x flags 553 */ 554 if (nverbose) 555 setNS(STRverbose); 556 if (nexececho) 557 setNS(STRecho); 558 559 /* 560 * All the rest of the world is inside this call. The argument to process 561 * indicates whether it should catch "error unwinds". Thus if we are a 562 * interactive shell our call here will never return by being blown past on 563 * an error. 564 */ 565 process(setintr); 566 567 /* 568 * Mop-up. 569 */ 570 if (intty) { 571 if (loginsh) { 572 (void)fprintf(cshout, "logout\n"); 573 (void)close(SHIN); 574 child = 1; 575 goodbye(); 576 } 577 else { 578 (void)fprintf(cshout, "exit\n"); 579 } 580 } 581 rechist(); 582 exitstat(); 583 /* NOTREACHED */ 584 } 585 586 void 587 untty(void) 588 { 589 if (tpgrp > 0) { 590 (void)setpgid(0, opgrp); 591 (void)tcsetpgrp(FSHTTY, opgrp); 592 } 593 } 594 595 void 596 importpath(Char *cp) 597 { 598 Char *dp, **pv; 599 int c, i; 600 601 i = 0; 602 for (dp = cp; *dp; dp++) 603 if (*dp == ':') 604 i++; 605 /* 606 * i+2 where i is the number of colons in the path. There are i+1 607 * directories in the path plus we need room for a zero terminator. 608 */ 609 pv = (Char **)xcalloc((size_t) (i + 2), sizeof(Char **)); 610 dp = cp; 611 i = 0; 612 if (*dp) 613 for (;;) { 614 if ((c = *dp) == ':' || c == 0) { 615 *dp = 0; 616 pv[i++] = Strsave(*cp ? cp : STRdot); 617 if (c) { 618 cp = dp + 1; 619 *dp = ':'; 620 } 621 else 622 break; 623 } 624 dp++; 625 } 626 pv[i] = 0; 627 setq(STRpath, pv, &shvhed); 628 } 629 630 /* 631 * Source to the file which is the catenation of the argument names. 632 */ 633 static int 634 srccat(Char *cp, Char *dp) 635 { 636 Char *ep; 637 char *ptr; 638 639 ep = Strspl(cp, dp); 640 ptr = short2str(ep); 641 xfree((ptr_t) ep); 642 return srcfile(ptr, mflag ? 0 : 1, 0); 643 } 644 645 /* 646 * Source to a file putting the file descriptor in a safe place (> 2). 647 */ 648 static int 649 srcfile(const char *f, int onlyown, int flag) 650 { 651 int unit; 652 653 if ((unit = open(f, O_RDONLY)) == -1) 654 return 0; 655 unit = dmove(unit, -1); 656 657 (void) ioctl(unit, FIOCLEX, NULL); 658 srcunit(unit, onlyown, flag); 659 return 1; 660 } 661 662 /* 663 * Source to a unit. If onlyown it must be our file or our group or 664 * we don't chance it. This occurs on ".cshrc"s and the like. 665 */ 666 int insource; 667 668 static void 669 srcunit(int unit, int onlyown, int hflg) 670 { 671 /* We have to push down a lot of state here */ 672 /* All this could go into a structure */ 673 struct whyle *oldwhyl; 674 struct Bin saveB; 675 sigset_t nsigset, osigset; 676 jmp_buf oldexit; 677 Char *oarginp, *oevalp, **oevalvec, *ogointr; 678 char OHIST; 679 int oSHIN, oinsource, oldintty, oonelflg; 680 int oenterhist, otell; 681 /* The (few) real local variables */ 682 int my_reenter; 683 684 oSHIN = -1; 685 oldintty = intty; 686 oinsource = insource; 687 oldwhyl = whyles; 688 ogointr = gointr; 689 oarginp = arginp; 690 oevalp = evalp; 691 oevalvec = evalvec; 692 oonelflg = onelflg; 693 oenterhist = enterhist; 694 OHIST = HIST; 695 otell = cantell; 696 697 if (unit < 0) 698 return; 699 if (didfds) 700 donefds(); 701 if (onlyown) { 702 struct stat stb; 703 704 if (fstat(unit, &stb) < 0) { 705 (void)close(unit); 706 return; 707 } 708 } 709 710 /* 711 * There is a critical section here while we are pushing down the input 712 * stream since we have stuff in different structures. If we weren't 713 * careful an interrupt could corrupt SHIN's Bin structure and kill the 714 * shell. 715 * 716 * We could avoid the critical region by grouping all the stuff in a single 717 * structure and pointing at it to move it all at once. This is less 718 * efficient globally on many variable references however. 719 */ 720 insource = 1; 721 getexit(oldexit); 722 723 if (setintr) { 724 sigemptyset(&nsigset); 725 (void)sigaddset(&nsigset, SIGINT); 726 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 727 } 728 /* Setup the new values of the state stuff saved above */ 729 (void)memcpy(&saveB, &B, sizeof(B)); 730 fbuf = NULL; 731 fseekp = feobp = fblocks = 0; 732 oSHIN = SHIN, SHIN = unit, arginp = 0, onelflg = 0; 733 intty = isatty(SHIN), whyles = 0, gointr = 0; 734 evalvec = 0; 735 evalp = 0; 736 enterhist = hflg; 737 if (enterhist) 738 HIST = '\0'; 739 740 /* 741 * Now if we are allowing commands to be interrupted, we let ourselves be 742 * interrupted. 743 */ 744 if (setintr) 745 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 746 settell(); 747 748 if ((my_reenter = setexit()) == 0) 749 process(0); /* 0 -> blow away on errors */ 750 751 if (setintr) 752 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 753 if (oSHIN >= 0) { 754 int i; 755 756 /* We made it to the new state... free up its storage */ 757 /* This code could get run twice but xfree doesn't care */ 758 for (i = 0; i < fblocks; i++) 759 xfree((ptr_t) fbuf[i]); 760 xfree((ptr_t) fbuf); 761 762 /* Reset input arena */ 763 (void)memcpy(&B, &saveB, sizeof(B)); 764 765 (void)close(SHIN), SHIN = oSHIN; 766 arginp = oarginp, onelflg = oonelflg; 767 evalp = oevalp, evalvec = oevalvec; 768 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 769 if (enterhist) 770 HIST = OHIST; 771 enterhist = oenterhist; 772 cantell = otell; 773 } 774 775 resexit(oldexit); 776 /* 777 * If process reset() (effectively an unwind) then we must also unwind. 778 */ 779 if (my_reenter) 780 stderror(ERR_SILENT); 781 insource = oinsource; 782 } 783 784 void 785 rechist(void) 786 { 787 Char buf[BUFSIZE], hbuf[BUFSIZE], *hfile; 788 int fp, ftmp, oldidfds; 789 struct varent *shist; 790 791 if (!fast) { 792 /* 793 * If $savehist is just set, we use the value of $history 794 * else we use the value in $savehist 795 */ 796 if ((shist = adrof(STRsavehist)) != NULL) { 797 if (shist->vec[0][0] != '\0') 798 (void)Strcpy(hbuf, shist->vec[0]); 799 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 800 (void)Strcpy(hbuf, shist->vec[0]); 801 else 802 return; 803 } 804 else 805 return; 806 807 if ((hfile = value(STRhistfile)) == STRNULL) { 808 hfile = Strcpy(buf, value(STRhome)); 809 (void) Strcat(buf, STRsldthist); 810 } 811 812 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 813 0600)) == -1) 814 return; 815 816 oldidfds = didfds; 817 didfds = 0; 818 ftmp = SHOUT; 819 SHOUT = fp; 820 dumphist[2] = hbuf; 821 dohist(dumphist, NULL); 822 SHOUT = ftmp; 823 (void)close(fp); 824 didfds = oldidfds; 825 } 826 } 827 828 void 829 goodbye(void) 830 { 831 rechist(); 832 833 if (loginsh) { 834 (void)signal(SIGQUIT, SIG_IGN); 835 (void)signal(SIGINT, SIG_IGN); 836 (void)signal(SIGTERM, SIG_IGN); 837 setintr = 0; /* No interrupts after "logout" */ 838 if (!(adrof(STRlogout))) 839 set(STRlogout, STRnormal); 840 #ifdef _PATH_DOTLOGOUT 841 (void)srcfile(_PATH_DOTLOGOUT, 0, 0); 842 #endif 843 if (adrof(STRhome)) 844 (void)srccat(value(STRhome), STRsldtlogout); 845 } 846 exitstat(); 847 /* NOTREACHED */ 848 } 849 850 __dead void 851 exitstat(void) 852 { 853 Char *s; 854 #ifdef PROF 855 monitor(0); 856 #endif 857 /* 858 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 859 * directly because we poke child here. Otherwise we might continue 860 * unwarrantedly (sic). 861 */ 862 child = 1; 863 s = value(STRstatus); 864 xexit(s ? getn(s) : 0); 865 /* NOTREACHED */ 866 } 867 868 /* 869 * in the event of a HUP we want to save the history 870 */ 871 static void 872 phup(int sig) 873 { 874 rechist(); 875 876 /* 877 * We kill the last foreground process group. It then becomes 878 * responsible to propagate the SIGHUP to its progeny. 879 */ 880 { 881 struct process *pp, *np; 882 883 for (pp = proclist.p_next; pp; pp = pp->p_next) { 884 np = pp; 885 /* 886 * Find if this job is in the foreground. It could be that 887 * the process leader has exited and the foreground flag 888 * is cleared for it. 889 */ 890 do 891 /* 892 * If a process is in the foreground; we try to kill 893 * its process group. If we succeed, then the 894 * whole job is gone. Otherwise we keep going... 895 * But avoid sending HUP to the shell again. 896 */ 897 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 898 kill(-np->p_jobid, SIGHUP) != -1) { 899 /* In case the job was suspended... */ 900 (void)kill(-np->p_jobid, SIGCONT); 901 break; 902 } 903 while ((np = np->p_friends) != pp); 904 } 905 } 906 xexit(sig); 907 /* NOTREACHED */ 908 } 909 910 Char *jobargv[2] = {STRjobs, 0}; 911 912 /* 913 * Catch an interrupt, e.g. during lexical input. 914 * If we are an interactive shell, we reset the interrupt catch 915 * immediately. In any case we drain the shell output, 916 * and finally go through the normal error mechanism, which 917 * gets a chance to make the shell go away. 918 */ 919 /* ARGSUSED */ 920 void 921 pintr(int notused) 922 { 923 pintr1(1); 924 /* NOTREACHED */ 925 } 926 927 void 928 pintr1(int wantnl) 929 { 930 Char **v; 931 sigset_t nsigset, osigset; 932 933 sigemptyset(&nsigset); 934 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 935 if (setintr) { 936 nsigset = osigset; 937 (void)sigdelset(&nsigset, SIGINT); 938 (void)sigprocmask(SIG_SETMASK, &nsigset, NULL); 939 if (pjobs) { 940 pjobs = 0; 941 (void)fprintf(cshout, "\n"); 942 dojobs(jobargv, NULL); 943 stderror(ERR_NAME | ERR_INTR); 944 } 945 } 946 (void)sigdelset(&osigset, SIGCHLD); 947 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 948 (void)fpurge(cshout); 949 (void)endpwent(); 950 951 /* 952 * If we have an active "onintr" then we search for the label. Note that if 953 * one does "onintr -" then we shan't be interruptible so we needn't worry 954 * about that here. 955 */ 956 if (gointr) { 957 gotolab(gointr); 958 timflg = 0; 959 if ((v = pargv) != NULL) 960 pargv = 0, blkfree(v); 961 if ((v = gargv) != NULL) 962 gargv = 0, blkfree(v); 963 reset(); 964 } 965 else if (intty && wantnl) { 966 (void)fputc('\r', cshout); 967 (void)fputc('\n', cshout); 968 } 969 stderror(ERR_SILENT); 970 /* NOTREACHED */ 971 } 972 973 /* 974 * Process is the main driving routine for the shell. 975 * It runs all command processing, except for those within { ... } 976 * in expressions (which is run by a routine evalav in sh.exp.c which 977 * is a stripped down process), and `...` evaluation which is run 978 * also by a subset of this code in sh.glob.c in the routine backeval. 979 * 980 * The code here is a little strange because part of it is interruptible 981 * and hence freeing of structures appears to occur when none is necessary 982 * if this is ignored. 983 * 984 * Note that if catch is not set then we will unwind on any error. 985 * If an end-of-file occurs, we return. 986 */ 987 static struct command *savet = NULL; 988 989 void 990 process(int catch) 991 { 992 struct command *t; 993 jmp_buf osetexit; 994 sigset_t nsigset; 995 996 t = savet; 997 savet = NULL; 998 getexit(osetexit); 999 for (;;) { 1000 pendjob(); 1001 paraml.next = paraml.prev = ¶ml; 1002 paraml.word = STRNULL; 1003 (void)setexit(); 1004 justpr = enterhist; /* execute if not entering history */ 1005 1006 /* 1007 * Interruptible during interactive reads 1008 */ 1009 if (setintr) { 1010 sigemptyset(&nsigset); 1011 (void)sigaddset(&nsigset, SIGINT); 1012 (void)sigprocmask(SIG_UNBLOCK, &nsigset, NULL); 1013 } 1014 1015 /* 1016 * For the sake of reset() 1017 */ 1018 freelex(¶ml); 1019 if (savet) 1020 freesyn(savet), savet = NULL; 1021 1022 if (haderr) { 1023 if (!catch) { 1024 /* unwind */ 1025 doneinp = 0; 1026 resexit(osetexit); 1027 savet = t; 1028 reset(); 1029 } 1030 haderr = 0; 1031 /* 1032 * Every error is eventually caught here or the shell dies. It is 1033 * at this point that we clean up any left-over open files, by 1034 * closing all but a fixed number of pre-defined files. Thus 1035 * routines don't have to worry about leaving files open due to 1036 * deeper errors... they will get closed here. 1037 */ 1038 closem(); 1039 continue; 1040 } 1041 if (doneinp) { 1042 doneinp = 0; 1043 break; 1044 } 1045 if (chkstop) 1046 chkstop--; 1047 if (neednote) 1048 pnote(); 1049 if (intty && prompt && evalvec == 0) { 1050 mailchk(); 1051 /* 1052 * If we are at the end of the input buffer then we are going to 1053 * read fresh stuff. Otherwise, we are rereading input and don't 1054 * need or want to prompt. 1055 */ 1056 if (aret == F_SEEK && fseekp == feobp) 1057 printprompt(); 1058 (void)fflush(cshout); 1059 } 1060 if (seterr) { 1061 xfree((ptr_t) seterr); 1062 seterr = NULL; 1063 } 1064 1065 /* 1066 * Echo not only on VERBOSE, but also with history expansion. If there 1067 * is a lexical error then we forego history echo. 1068 */ 1069 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1070 int odidfds = didfds; 1071 fflush(csherr); 1072 didfds = 0; 1073 prlex(csherr, ¶ml); 1074 fflush(csherr); 1075 didfds = odidfds; 1076 } 1077 1078 /* 1079 * The parser may lose space if interrupted. 1080 */ 1081 if (setintr) 1082 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 1083 1084 /* 1085 * Save input text on the history list if reading in old history, or it 1086 * is from the terminal at the top level and not in a loop. 1087 * 1088 * PWP: entry of items in the history list while in a while loop is done 1089 * elsewhere... 1090 */ 1091 if (enterhist || (catch && intty && !whyles)) 1092 savehist(¶ml); 1093 1094 /* 1095 * Print lexical error messages, except when sourcing history lists. 1096 */ 1097 if (!enterhist && seterr) 1098 stderror(ERR_OLD); 1099 1100 /* 1101 * If had a history command :p modifier then this is as far as we 1102 * should go 1103 */ 1104 if (justpr) 1105 reset(); 1106 1107 alias(¶ml); 1108 1109 /* 1110 * Parse the words of the input into a parse tree. 1111 */ 1112 savet = syntax(paraml.next, ¶ml, 0); 1113 if (seterr) 1114 stderror(ERR_OLD); 1115 1116 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1117 1118 /* 1119 * Made it! 1120 */ 1121 freelex(¶ml); 1122 freesyn((struct command *) savet), savet = NULL; 1123 } 1124 resexit(osetexit); 1125 savet = t; 1126 } 1127 1128 void 1129 /*ARGSUSED*/ 1130 dosource(Char **v, struct command *t) 1131 { 1132 Char buf[BUFSIZE], *f; 1133 int hflg; 1134 1135 hflg = 0; 1136 v++; 1137 if (*v && eq(*v, STRmh)) { 1138 if (*++v == NULL) 1139 stderror(ERR_NAME | ERR_HFLAG); 1140 hflg++; 1141 } 1142 (void)Strcpy(buf, *v); 1143 f = globone(buf, G_ERROR); 1144 (void)strcpy((char *)buf, short2str(f)); 1145 xfree((ptr_t) f); 1146 if (!srcfile((char *)buf, 0, hflg) && !hflg) 1147 stderror(ERR_SYSTEM, (char *)buf, strerror(errno)); 1148 } 1149 1150 /* 1151 * Check for mail. 1152 * If we are a login shell, then we don't want to tell 1153 * about any mail file unless its been modified 1154 * after the time we started. 1155 * This prevents us from telling the user things he already 1156 * knows, since the login program insists on saying 1157 * "You have mail." 1158 */ 1159 static void 1160 mailchk(void) 1161 { 1162 struct stat stb; 1163 struct varent *v; 1164 Char **vp; 1165 time_t t; 1166 int cnt, intvl; 1167 int new; 1168 1169 v = adrof(STRmail); 1170 if (v == 0) 1171 return; 1172 (void)time(&t); 1173 vp = v->vec; 1174 cnt = blklen(vp); 1175 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1176 if (intvl < 1) 1177 intvl = 1; 1178 if (chktim + intvl > t) 1179 return; 1180 for (; *vp; vp++) { 1181 if (stat(short2str(*vp), &stb) < 0) 1182 continue; 1183 new = stb.st_mtime > time0.tv_sec; 1184 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1185 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1186 (loginsh && !new)) 1187 continue; 1188 if (cnt == 1) 1189 (void)fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1190 else 1191 (void)fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1192 vis_str(*vp)); 1193 } 1194 chktim = t; 1195 } 1196 1197 /* 1198 * Extract a home directory from the password file 1199 * The argument points to a buffer where the name of the 1200 * user whose home directory is sought is currently. 1201 * We write the home directory of the user back there. 1202 */ 1203 int 1204 gethdir(Char *home) 1205 { 1206 struct passwd *pw; 1207 Char *h; 1208 1209 /* 1210 * Is it us? 1211 */ 1212 if (*home == '\0') { 1213 if ((h = value(STRhome)) != NULL) { 1214 (void)Strcpy(home, h); 1215 return 0; 1216 } 1217 else 1218 return 1; 1219 } 1220 1221 if ((pw = getpwnam(short2str(home))) != NULL) { 1222 (void)Strcpy(home, str2short(pw->pw_dir)); 1223 return 0; 1224 } 1225 else 1226 return 1; 1227 } 1228 1229 /* 1230 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1231 * We also check if the shell has already changed the descriptor to point to 1232 * 0, 1, 2 when didfds is set. 1233 */ 1234 #define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1235 1236 static int 1237 readf(void *oreo, char *buf, int siz) 1238 { 1239 return read(DESC(oreo), buf, siz); 1240 } 1241 1242 1243 static int 1244 writef(void *oreo, const char *buf, int siz) 1245 { 1246 return write(DESC(oreo), buf, siz); 1247 } 1248 1249 static off_t 1250 seekf(void *oreo, off_t off, int whence) 1251 { 1252 return lseek(DESC(oreo), off, whence); 1253 } 1254 1255 1256 static int 1257 closef(void *oreo) 1258 { 1259 return close(DESC(oreo)); 1260 } 1261 1262 1263 /* 1264 * Print the visible version of a string. 1265 */ 1266 int 1267 vis_fputc(int ch, FILE *fp) 1268 { 1269 char uenc[5]; /* 4 + NULL */ 1270 1271 if (ch & QUOTE) 1272 return fputc(ch & TRIM, fp); 1273 /* 1274 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1275 * be encoded, but currently there is no way in vis to do that. 1276 */ 1277 (void)vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1278 return (fputs(uenc, fp)); 1279 } 1280 1281 /* 1282 * Move the initial descriptors to their eventual 1283 * resting places, closing all other units. 1284 */ 1285 void 1286 initdesc(void) 1287 { 1288 didfds = 0; /* 0, 1, 2 aren't set up */ 1289 (void)ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1290 (void)ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1291 (void)ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1292 (void)ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1293 closem(); 1294 } 1295 1296 1297 __dead void 1298 #ifdef PROF 1299 done(int i) 1300 #else 1301 xexit(int i) 1302 #endif 1303 { 1304 untty(); 1305 _exit(i); 1306 /* NOTREACHED */ 1307 } 1308 1309 #ifndef _PATH_DEFPATH 1310 static Char ** 1311 defaultpath(void) 1312 { 1313 struct stat stb; 1314 Char **blk, **blkp; 1315 char *ptr; 1316 1317 blkp = blk = (Char **)xmalloc((size_t) sizeof(Char *) * 10); 1318 1319 #define DIRAPPEND(a) \ 1320 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1321 *blkp++ = SAVE(ptr) 1322 #ifdef RESCUEDIR 1323 DIRAPPEND(RESCUEDIR); 1324 #endif 1325 DIRAPPEND(_PATH_BIN); 1326 DIRAPPEND(_PATH_USRBIN); 1327 1328 #undef DIRAPPEND 1329 1330 #if 0 1331 if (euid != 0 && uid != 0) 1332 *blkp++ = Strsave(STRdot); 1333 #endif 1334 1335 *blkp = NULL; 1336 return (blk); 1337 } 1338 #endif /* _PATH_DEFPATH */ 1339 1340 void 1341 printprompt(void) 1342 { 1343 Char *cp; 1344 1345 if (editing) 1346 return; 1347 1348 if (!whyles) { 1349 for (cp = value(STRprompt); *cp; cp++) 1350 if (*cp == HIST) 1351 (void)fprintf(cshout, "%d", eventno + 1); 1352 else { 1353 if (*cp == '\\' && cp[1] == HIST) 1354 cp++; 1355 (void)vis_fputc(*cp | QUOTE, cshout); 1356 } 1357 } 1358 else 1359 /* 1360 * Prompt for forward reading loop body content. 1361 */ 1362 (void)fprintf(cshout, "? "); 1363 (void)fflush(cshout); 1364 } 1365 1366 #ifdef EDIT 1367 char * 1368 printpromptstr(EditLine *elx) { 1369 static char pbuf[1024]; 1370 static char qspace[] = "? "; 1371 Char *cp; 1372 size_t i; 1373 1374 if (whyles) 1375 return qspace; 1376 1377 i = 0; 1378 for (cp = value(STRprompt); *cp; cp++) { 1379 if (i >= sizeof(pbuf)) 1380 break; 1381 if (*cp == HIST) 1382 i += snprintf(pbuf + i, sizeof(pbuf) - i, "%d", eventno + 1); 1383 else 1384 pbuf[i++] = *cp; 1385 } 1386 if (i >= sizeof(pbuf)) 1387 i = sizeof(pbuf) - 1; 1388 pbuf[i] = '\0'; 1389 return pbuf; 1390 } 1391 #endif 1392