1 /* $NetBSD: csh.c,v 1.56 2022/09/15 11:35:06 martin 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 1.56 2022/09/15 11:35:06 martin 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 FILE *cshin, *cshout, *csherr; 81 struct timespec time0; 82 struct rusage ru0; 83 struct varent shvhed, aliases; 84 Char HISTSUB; 85 int editing; 86 87 int child; 88 int chkstop; 89 int didfds; 90 int doneinp; 91 int exiterr; 92 int haderr; 93 int havhash; 94 int intact; 95 int intty; 96 int justpr; 97 int loginsh; 98 int neednote; 99 int noexec; 100 int pjobs; 101 int setintr; 102 int timflg; 103 104 Char *arginp; 105 Char *ffile; 106 int onelflg; 107 Char *shtemp; 108 109 time_t chktim; 110 Char *doldol; 111 pid_t backpid; 112 gid_t egid, gid; 113 uid_t euid, uid; 114 int shpgrp; 115 int tpgrp; 116 117 int opgrp; 118 119 int SHIN; 120 int SHOUT; 121 int SHERR; 122 int OLDSTD; 123 124 jmp_buf reslab; 125 126 Char *gointr; 127 128 sig_t parintr; 129 sig_t parterm; 130 131 struct Bin B; 132 133 struct Ain lineloc; 134 int cantell; 135 Char *lap; 136 struct whyle *whyles; 137 138 struct wordent *alhistp,*alhistt; 139 140 int AsciiOnly; 141 int gflag; 142 long pnleft; 143 Char *pargs; 144 Char *pargcp; 145 struct Hist Histlist; 146 struct wordent paraml; 147 int eventno; 148 int lastev; 149 Char HIST; 150 Char HISTSUB; 151 const char *bname; 152 Char *Vsav; 153 Char *Vdp; 154 Char *Vexpath; 155 char **Vt; 156 Char **evalvec; 157 Char *evalp; 158 Char *word_chars; 159 Char *STR_SHELLPATH; 160 #ifdef _PATH_BSHELL 161 Char *STR_BSHELL; 162 #endif 163 Char *STR_WORD_CHARS; 164 Char **STR_environ; 165 #ifdef EDIT 166 EditLine *el; 167 History *hi; 168 #endif 169 int editing; 170 171 Char *dumphist[] = {STRhistory, STRmh, 0, 0}; 172 Char *tildehist[] = {STRsource, STRmh, STRtildothist, 0}; 173 174 int nofile = 0; 175 int batch = 0; 176 int enterhist = 0; 177 int fast = 0; 178 int mflag = 0; 179 int nexececho = 0; 180 int nverbose = 0; 181 int prompt = 1; 182 int quitit = 0; 183 int reenter = 0; 184 185 extern char **environ; 186 187 static ssize_t readf(void *, void *, size_t); 188 static off_t seekf(void *, off_t, int); 189 static ssize_t writef(void *, const void *, size_t); 190 static int closef(void *); 191 static int srccat(Char *, Char *); 192 static int srcfile(const char *, int, int); 193 __dead static void phup(int); 194 static void srcunit(int, int, int); 195 static void mailchk(void); 196 #ifndef _PATH_DEFPATH 197 static Char **defaultpath(void); 198 #endif 199 200 int 201 main(int argc, char *argv[]) 202 { 203 struct sigaction oact; 204 Char *cp; 205 char *tcp, **tempv; 206 const char *ecp; 207 sigset_t nsigset; 208 int f; 209 210 cshin = stdin; 211 cshout = stdout; 212 csherr = stderr; 213 214 setprogname(argv[0]); 215 settimes(); /* Immed. estab. timing base */ 216 217 /* 218 * Initialize non constant strings 219 */ 220 #ifdef _PATH_BSHELL 221 STR_BSHELL = SAVE(_PATH_BSHELL); 222 #endif 223 #ifdef _PATH_CSHELL 224 STR_SHELLPATH = SAVE(_PATH_CSHELL); 225 #endif 226 STR_environ = blk2short(environ); 227 environ = short2blk(STR_environ); /* So that we can free it */ 228 STR_WORD_CHARS = SAVE(WORD_CHARS); 229 230 HIST = '!'; 231 HISTSUB = '^'; 232 word_chars = STR_WORD_CHARS; 233 234 tempv = argv; 235 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 236 quitit = 1; 237 uid = getuid(); 238 gid = getgid(); 239 euid = geteuid(); 240 egid = getegid(); 241 /* 242 * We are a login shell if: 1. we were invoked as -<something> and we had 243 * no arguments 2. or we were invoked only with the -l flag 244 */ 245 loginsh = (**tempv == '-' && argc == 1) || 246 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 247 tempv[1][2] == '\0'); 248 249 if (loginsh && **tempv != '-') { 250 /* 251 * Mangle the argv space 252 */ 253 tempv[1][0] = '\0'; 254 tempv[1][1] = '\0'; 255 tempv[1] = NULL; 256 for (tcp = *tempv; *tcp++;) 257 continue; 258 for (tcp--; tcp >= *tempv; tcp--) 259 tcp[1] = tcp[0]; 260 *++tcp = '-'; 261 argc--; 262 } 263 if (loginsh) 264 (void)time(&chktim); 265 266 AsciiOnly = 1; 267 #ifdef NLS 268 (void)setlocale(LC_ALL, ""); 269 { 270 int k; 271 272 for (k = 0200; k <= 0377 && !Isprint(k); k++) 273 continue; 274 AsciiOnly = k > 0377; 275 } 276 #else 277 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 278 #endif /* NLS */ 279 280 /* 281 * Move the descriptors to safe places. The variable didfds is 0 while we 282 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 283 * prefer to use these. 284 */ 285 initdesc(); 286 /* 287 * XXX: This is to keep programs that use stdio happy. 288 * what we really want is freunopen() .... 289 * Closing cshin cshout and csherr (which are really stdin stdout 290 * and stderr at this point and then reopening them in the same order 291 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 292 * If that was not the case builtins like printf that use stdio 293 * would break. But in any case we could fix that with memcpy and 294 * a bit of pointer manipulation... 295 * Fortunately this is not needed under the current implementation 296 * of stdio. 297 */ 298 (void)fclose(cshin); 299 (void)fclose(cshout); 300 (void)fclose(csherr); 301 if (!(cshin = funopen2((void *) &SHIN, readf, writef, seekf, NULL, 302 closef))) 303 exit(1); 304 if (!(cshout = funopen2((void *) &SHOUT, readf, writef, seekf, NULL, 305 closef))) 306 exit(1); 307 if (!(csherr = funopen2((void *) &SHERR, readf, writef, seekf, NULL, 308 closef))) 309 exit(1); 310 (void)setvbuf(cshin, NULL, _IOLBF, 0); 311 (void)setvbuf(cshout, NULL, _IOLBF, 0); 312 (void)setvbuf(csherr, NULL, _IOLBF, 0); 313 314 /* 315 * Initialize the shell variables. ARGV and PROMPT are initialized later. 316 * STATUS is also munged in several places. CHILD is munged when 317 * forking/waiting 318 */ 319 set(STRstatus, Strsave(STR0)); 320 321 if ((ecp = getenv("HOME")) != NULL) 322 cp = quote(SAVE(ecp)); 323 else 324 cp = NULL; 325 326 if (cp == NULL) 327 fast = 1; /* No home -> can't read scripts */ 328 else 329 set(STRhome, cp); 330 dinit(cp); /* dinit thinks that HOME == cwd in a login 331 * shell */ 332 /* 333 * Grab other useful things from the environment. Should we grab 334 * everything?? 335 */ 336 if ((ecp = getenv("LOGNAME")) != NULL || 337 (ecp = getenv("USER")) != NULL) 338 set(STRuser, quote(SAVE(ecp))); 339 if ((ecp = getenv("TERM")) != NULL) 340 set(STRterm, quote(SAVE(ecp))); 341 342 /* 343 * Re-initialize path if set in environment 344 */ 345 if ((ecp = getenv("PATH")) == NULL) { 346 #ifdef _PATH_DEFPATH 347 importpath(str2short(_PATH_DEFPATH)); 348 #else 349 setq(STRpath, defaultpath(), &shvhed); 350 #endif 351 } else { 352 importpath(str2short(ecp)); 353 } 354 355 set(STRshell, Strsave(STR_SHELLPATH)); 356 357 doldol = putn((int) getpid()); /* For $$ */ 358 shtemp = Strspl(STRtmpsh, doldol); /* For << */ 359 360 /* 361 * Record the interrupt states from the parent process. If the parent is 362 * non-interruptible our hand must be forced or we (and our children) won't 363 * be either. Our children inherit termination from our parent. We catch it 364 * only if we are the login shell. 365 */ 366 /* parents interruptibility */ 367 (void)sigaction(SIGINT, NULL, &oact); 368 parintr = oact.sa_handler; 369 (void)sigaction(SIGTERM, NULL, &oact); 370 parterm = oact.sa_handler; 371 372 /* catch these all, login shell or not */ 373 (void)signal(SIGHUP, phup); /* exit processing on HUP */ 374 (void)signal(SIGXCPU, phup); /* ...and on XCPU */ 375 (void)signal(SIGXFSZ, phup); /* ...and on XFSZ */ 376 377 /* 378 * Process the arguments. 379 * 380 * Note that processing of -v/-x is actually delayed till after script 381 * processing. 382 * 383 * We set the first character of our name to be '-' if we are a shell 384 * running interruptible commands. Many programs which examine ps'es 385 * use this to filter such shells out. 386 */ 387 argc--, tempv++; 388 while (argc > 0 && (tcp = tempv[0])[0] == '-' && *++tcp != '\0' && !batch) { 389 do 390 switch (*tcp++) { 391 case 0: /* - Interruptible, no prompt */ 392 prompt = 0; 393 setintr = 1; 394 nofile = 1; 395 break; 396 case 'b': /* -b Next arg is input file */ 397 batch = 1; 398 break; 399 case 'c': /* -c Command input from arg */ 400 if (argc == 1) 401 xexit(0); 402 argc--, tempv++; 403 arginp = SAVE(tempv[0]); 404 prompt = 0; 405 nofile = 1; 406 break; 407 case 'e': /* -e Exit on any error */ 408 exiterr = 1; 409 break; 410 case 'f': /* -f Fast start */ 411 fast = 1; 412 break; 413 case 'i': /* -i Interactive, even if !intty */ 414 intact = 1; 415 nofile = 1; 416 break; 417 case 'm': /* -m read .cshrc (from su) */ 418 mflag = 1; 419 break; 420 case 'n': /* -n Don't execute */ 421 noexec = 1; 422 break; 423 case 'q': /* -q (Undoc'd) ... die on quit */ 424 quitit = 1; 425 break; 426 case 's': /* -s Read from std input */ 427 nofile = 1; 428 break; 429 case 't': /* -t Read one line from input */ 430 onelflg = 2; 431 prompt = 0; 432 nofile = 1; 433 break; 434 case 'v': /* -v Echo hist expanded input */ 435 nverbose = 1; /* ... later */ 436 break; 437 case 'x': /* -x Echo just before execution */ 438 nexececho = 1; /* ... later */ 439 break; 440 case 'V': /* -V Echo hist expanded input */ 441 setNS(STRverbose); /* NOW! */ 442 break; 443 case 'X': /* -X Echo just before execution */ 444 setNS(STRecho); /* NOW! */ 445 break; 446 447 } while (*tcp); 448 tempv++, argc--; 449 } 450 451 if (quitit) /* With all due haste, for debugging */ 452 (void)signal(SIGQUIT, SIG_DFL); 453 454 /* 455 * Unless prevented by -, -c, -i, -s, or -t, if there are remaining 456 * arguments the first of them is the name of a shell file from which to 457 * read commands. 458 */ 459 if (nofile == 0 && argc > 0) { 460 nofile = open(tempv[0], O_RDONLY); 461 if (nofile < 0) { 462 child = 1; /* So this doesn't return */ 463 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 464 } 465 ffile = SAVE(tempv[0]); 466 /* 467 * Replace FSHIN. Handle /dev/std{in,out,err} specially 468 * since once they are closed we cannot open them again. 469 * In that case we use our own saved descriptors 470 */ 471 if ((SHIN = dmove(nofile, FSHIN)) < 0) 472 switch(nofile) { 473 case 0: 474 SHIN = FSHIN; 475 break; 476 case 1: 477 SHIN = FSHOUT; 478 break; 479 case 2: 480 SHIN = FSHERR; 481 break; 482 default: 483 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 484 /* NOTREACHED */ 485 } 486 (void)ioctl(SHIN, FIOCLEX, NULL); 487 prompt = 0; 488 /* argc not used any more */ tempv++; 489 } 490 491 intty = isatty(SHIN); 492 intty |= intact; 493 if (intty || (intact && isatty(SHOUT))) { 494 if (!batch && (uid != euid || gid != egid)) { 495 errno = EACCES; 496 child = 1; /* So this doesn't return */ 497 stderror(ERR_SYSTEM, "csh", strerror(errno)); 498 } 499 } 500 /* 501 * Decide whether we should play with signals or not. If we are explicitly 502 * told (via -i, or -) or we are a login shell (arg0 starts with -) or the 503 * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx") 504 * Note that in only the login shell is it likely that parent may have set 505 * signals to be ignored 506 */ 507 if (loginsh || intact || (intty && isatty(SHOUT))) 508 setintr = 1; 509 settell(); 510 /* 511 * Save the remaining arguments in argv. 512 */ 513 setq(STRargv, blk2short(tempv), &shvhed); 514 515 /* 516 * Set up the prompt. 517 */ 518 if (prompt) { 519 set(STRprompt, Strsave(uid == 0 ? STRsymhash : STRsymcent)); 520 /* that's a meta-questionmark */ 521 set(STRprompt2, Strsave(STRmquestion)); 522 } 523 524 /* 525 * If we are an interactive shell, then start fiddling with the signals; 526 * this is a tricky game. 527 */ 528 shpgrp = getpgrp(); 529 opgrp = tpgrp = -1; 530 if (setintr) { 531 **argv = '-'; 532 if (!quitit) /* Wary! */ 533 (void)signal(SIGQUIT, SIG_IGN); 534 (void)signal(SIGINT, pintr); 535 sigemptyset(&nsigset); 536 (void)sigaddset(&nsigset, SIGINT); 537 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 538 (void)signal(SIGTERM, SIG_IGN); 539 if (quitit == 0 && arginp == 0) { 540 (void)signal(SIGTSTP, SIG_IGN); 541 (void)signal(SIGTTIN, SIG_IGN); 542 (void)signal(SIGTTOU, SIG_IGN); 543 /* 544 * Wait till in foreground, in case someone stupidly runs csh & 545 * dont want to try to grab away the tty. 546 */ 547 if (isatty(FSHERR)) 548 f = FSHERR; 549 else if (isatty(FSHOUT)) 550 f = FSHOUT; 551 else if (isatty(OLDSTD)) 552 f = OLDSTD; 553 else 554 f = -1; 555 retry: 556 if ((tpgrp = tcgetpgrp(f)) != -1) { 557 if (tpgrp != shpgrp) { 558 sig_t old = signal(SIGTTIN, SIG_DFL); 559 (void)kill(0, SIGTTIN); 560 (void)signal(SIGTTIN, old); 561 goto retry; 562 } 563 opgrp = shpgrp; 564 shpgrp = getpid(); 565 tpgrp = shpgrp; 566 /* 567 * Setpgid will fail if we are a session leader and 568 * mypid == mypgrp (POSIX 4.3.3) 569 */ 570 if (opgrp != shpgrp) 571 if (setpgid(0, shpgrp) == -1) 572 goto notty; 573 /* 574 * We do that after we set our process group, to make sure 575 * that the process group belongs to a process in the same 576 * session as the tty (our process and our group) (POSIX 7.2.4) 577 */ 578 if (tcsetpgrp(f, shpgrp) == -1) 579 goto notty; 580 (void)ioctl(dcopy(f, FSHTTY), FIOCLEX, NULL); 581 } 582 if (tpgrp == -1) { 583 notty: 584 (void)fprintf(csherr, "Warning: no access to tty (%s).\n", 585 strerror(errno)); 586 (void)fprintf(csherr, "Thus no job control in this shell.\n"); 587 } 588 } 589 } 590 if ((setintr == 0) && (parintr == SIG_DFL)) 591 setintr = 1; 592 (void)signal(SIGCHLD, pchild); /* while signals not ready */ 593 594 /* 595 * Set an exit here in case of an interrupt or error reading the shell 596 * start-up scripts. 597 */ 598 reenter = setexit(); /* PWP */ 599 haderr = 0; /* In case second time through */ 600 if (!fast && reenter == 0) { 601 /* Will have value(STRhome) here because set fast if don't */ 602 { 603 sig_t oparintr; 604 sigset_t osigset; 605 int osetintr; 606 607 oparintr = parintr; 608 osetintr = setintr; 609 sigemptyset(&nsigset); 610 (void)sigaddset(&nsigset, SIGINT); 611 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 612 613 setintr = 0; 614 parintr = SIG_IGN; /* Disable onintr */ 615 #ifdef _PATH_DOTCSHRC 616 (void)srcfile(_PATH_DOTCSHRC, 0, 0); 617 #endif 618 if (!fast && !arginp && !onelflg) 619 dohash(NULL, NULL); 620 #ifdef _PATH_DOTLOGIN 621 if (loginsh) 622 (void)srcfile(_PATH_DOTLOGIN, 0, 0); 623 #endif 624 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 625 setintr = osetintr; 626 parintr = oparintr; 627 } 628 (void)srccat(value(STRhome), STRsldotcshrc); 629 630 if (!fast && !arginp && !onelflg && !havhash) 631 dohash(NULL, NULL); 632 /* 633 * Source history before .login so that it is available in .login 634 */ 635 if ((cp = value(STRhistfile)) != STRNULL) 636 tildehist[2] = cp; 637 dosource(tildehist, NULL); 638 if (loginsh) 639 (void)srccat(value(STRhome), STRsldotlogin); 640 } 641 642 /* 643 * Now are ready for the -v and -x flags 644 */ 645 if (nverbose) 646 setNS(STRverbose); 647 if (nexececho) 648 setNS(STRecho); 649 650 /* 651 * All the rest of the world is inside this call. The argument to process 652 * indicates whether it should catch "error unwinds". Thus if we are a 653 * interactive shell our call here will never return by being blown past on 654 * an error. 655 */ 656 process(setintr); 657 658 /* 659 * Mop-up. 660 */ 661 if (intty) { 662 if (loginsh) { 663 (void)fprintf(cshout, "logout\n"); 664 (void)close(SHIN); 665 child = 1; 666 goodbye(); 667 } 668 else { 669 (void)fprintf(cshout, "exit\n"); 670 } 671 } 672 rechist(); 673 exitstat(); 674 /* NOTREACHED */ 675 } 676 677 void 678 untty(void) 679 { 680 if (tpgrp > 0) { 681 (void)setpgid(0, opgrp); 682 (void)tcsetpgrp(FSHTTY, opgrp); 683 } 684 } 685 686 void 687 importpath(Char *cp) 688 { 689 Char *dp, **pv; 690 int c, i; 691 692 i = 0; 693 for (dp = cp; *dp; dp++) 694 if (*dp == ':') 695 i++; 696 /* 697 * i+2 where i is the number of colons in the path. There are i+1 698 * directories in the path plus we need room for a zero terminator. 699 */ 700 pv = xcalloc((size_t) (i + 2), sizeof(*pv)); 701 dp = cp; 702 i = 0; 703 if (*dp) 704 for (;;) { 705 if ((c = *dp) == ':' || c == 0) { 706 *dp = 0; 707 pv[i++] = Strsave(*cp ? cp : STRdot); 708 if (c) { 709 cp = dp + 1; 710 *dp = ':'; 711 } 712 else 713 break; 714 } 715 dp++; 716 } 717 pv[i] = 0; 718 setq(STRpath, pv, &shvhed); 719 } 720 721 /* 722 * Source to the file which is the catenation of the argument names. 723 */ 724 static int 725 srccat(Char *cp, Char *dp) 726 { 727 Char *ep; 728 char *ptr; 729 730 ep = Strspl(cp, dp); 731 ptr = short2str(ep); 732 free(ep); 733 return srcfile(ptr, mflag ? 0 : 1, 0); 734 } 735 736 /* 737 * Source to a file putting the file descriptor in a safe place (> 2). 738 */ 739 static int 740 srcfile(const char *f, int onlyown, int flag) 741 { 742 int unit; 743 744 if ((unit = open(f, O_RDONLY)) == -1) 745 return 0; 746 unit = dmove(unit, -1); 747 748 (void) ioctl(unit, FIOCLEX, NULL); 749 srcunit(unit, onlyown, flag); 750 return 1; 751 } 752 753 /* 754 * Source to a unit. If onlyown it must be our file or our group or 755 * we don't chance it. This occurs on ".cshrc"s and the like. 756 */ 757 int insource; 758 759 static void 760 srcunit(int unit, int onlyown, int hflg) 761 { 762 /* We have to push down a lot of state here */ 763 /* All this could go into a structure */ 764 struct whyle *oldwhyl; 765 struct Bin saveB; 766 sigset_t nsigset, osigset; 767 jmp_buf oldexit; 768 Char *oarginp, *oevalp, **oevalvec, *ogointr; 769 Char OHIST; 770 int oSHIN, oinsource, oldintty, oonelflg; 771 int oenterhist, otell; 772 /* The (few) real local variables */ 773 int my_reenter; 774 775 oSHIN = -1; 776 oldintty = intty; 777 oinsource = insource; 778 oldwhyl = whyles; 779 ogointr = gointr; 780 oarginp = arginp; 781 oevalp = evalp; 782 oevalvec = evalvec; 783 oonelflg = onelflg; 784 oenterhist = enterhist; 785 OHIST = HIST; 786 otell = cantell; 787 788 if (unit < 0) 789 return; 790 if (didfds) 791 donefds(); 792 if (onlyown) { 793 struct stat stb; 794 795 if (fstat(unit, &stb) < 0) { 796 (void)close(unit); 797 return; 798 } 799 } 800 801 /* 802 * There is a critical section here while we are pushing down the input 803 * stream since we have stuff in different structures. If we weren't 804 * careful an interrupt could corrupt SHIN's Bin structure and kill the 805 * shell. 806 * 807 * We could avoid the critical region by grouping all the stuff in a single 808 * structure and pointing at it to move it all at once. This is less 809 * efficient globally on many variable references however. 810 */ 811 insource = 1; 812 getexit(oldexit); 813 814 if (setintr) { 815 sigemptyset(&nsigset); 816 (void)sigaddset(&nsigset, SIGINT); 817 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 818 } 819 /* Setup the new values of the state stuff saved above */ 820 (void)memcpy(&saveB, &B, sizeof(B)); 821 fbuf = NULL; 822 fseekp = feobp = fblocks = 0; 823 oSHIN = SHIN, SHIN = unit, arginp = 0, onelflg = 0; 824 intty = isatty(SHIN), whyles = 0, gointr = 0; 825 evalvec = 0; 826 evalp = 0; 827 enterhist = hflg; 828 if (enterhist) 829 HIST = '\0'; 830 831 /* 832 * Now if we are allowing commands to be interrupted, we let ourselves be 833 * interrupted. 834 */ 835 if (setintr) 836 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 837 settell(); 838 839 if ((my_reenter = setexit()) == 0) 840 process(0); /* 0 -> blow away on errors */ 841 842 if (setintr) 843 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 844 if (oSHIN >= 0) { 845 int i; 846 847 /* We made it to the new state... free up its storage */ 848 for (i = 0; i < fblocks; i++) 849 free(fbuf[i]); 850 free(fbuf); 851 852 /* Reset input arena */ 853 /* (note that this clears fbuf and fblocks) */ 854 (void)memcpy(&B, &saveB, sizeof(B)); 855 856 (void)close(SHIN), SHIN = oSHIN; 857 arginp = oarginp, onelflg = oonelflg; 858 evalp = oevalp, evalvec = oevalvec; 859 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 860 if (enterhist) 861 HIST = OHIST; 862 enterhist = oenterhist; 863 cantell = otell; 864 } 865 866 resexit(oldexit); 867 /* 868 * If process reset() (effectively an unwind) then we must also unwind. 869 */ 870 if (my_reenter) 871 stderror(ERR_SILENT); 872 insource = oinsource; 873 } 874 875 void 876 rechist(void) 877 { 878 Char buf[BUFSIZE], hbuf[BUFSIZE], *hfile; 879 int fp, ftmp, oldidfds; 880 struct varent *shist; 881 882 if (!fast) { 883 /* 884 * If $savehist is just set, we use the value of $history 885 * else we use the value in $savehist 886 */ 887 if ((shist = adrof(STRsavehist)) != NULL) { 888 if (shist->vec[0][0] != '\0') 889 (void)Strcpy(hbuf, shist->vec[0]); 890 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 891 (void)Strcpy(hbuf, shist->vec[0]); 892 else 893 return; 894 } 895 else 896 return; 897 898 if ((hfile = value(STRhistfile)) == STRNULL) { 899 hfile = Strcpy(buf, value(STRhome)); 900 (void) Strcat(buf, STRsldthist); 901 } 902 903 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 904 0600)) == -1) 905 return; 906 907 oldidfds = didfds; 908 didfds = 0; 909 ftmp = SHOUT; 910 SHOUT = fp; 911 dumphist[2] = hbuf; 912 dohist(dumphist, NULL); 913 SHOUT = ftmp; 914 (void)close(fp); 915 didfds = oldidfds; 916 } 917 } 918 919 void 920 goodbye(void) 921 { 922 rechist(); 923 924 if (loginsh) { 925 (void)signal(SIGQUIT, SIG_IGN); 926 (void)signal(SIGINT, SIG_IGN); 927 (void)signal(SIGTERM, SIG_IGN); 928 setintr = 0; /* No interrupts after "logout" */ 929 if (!(adrof(STRlogout))) 930 set(STRlogout, STRnormal); 931 #ifdef _PATH_DOTLOGOUT 932 (void)srcfile(_PATH_DOTLOGOUT, 0, 0); 933 #endif 934 if (adrof(STRhome)) 935 (void)srccat(value(STRhome), STRsldtlogout); 936 } 937 exitstat(); 938 /* NOTREACHED */ 939 } 940 941 __dead void 942 exitstat(void) 943 { 944 Char *s; 945 #ifdef PROF 946 monitor(0); 947 #endif 948 /* 949 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 950 * directly because we poke child here. Otherwise we might continue 951 * unwarrantedly (sic). 952 */ 953 child = 1; 954 s = value(STRstatus); 955 xexit(s ? getn(s) : 0); 956 /* NOTREACHED */ 957 } 958 959 /* 960 * in the event of a HUP we want to save the history 961 */ 962 static void 963 phup(int sig) 964 { 965 rechist(); 966 967 /* 968 * We kill the last foreground process group. It then becomes 969 * responsible to propagate the SIGHUP to its progeny. 970 */ 971 { 972 struct process *pp, *np; 973 974 for (pp = proclist.p_next; pp; pp = pp->p_next) { 975 np = pp; 976 /* 977 * Find if this job is in the foreground. It could be that 978 * the process leader has exited and the foreground flag 979 * is cleared for it. 980 */ 981 do 982 /* 983 * If a process is in the foreground; we try to kill 984 * its process group. If we succeed, then the 985 * whole job is gone. Otherwise we keep going... 986 * But avoid sending HUP to the shell again. 987 */ 988 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 989 kill(-np->p_jobid, SIGHUP) != -1) { 990 /* In case the job was suspended... */ 991 (void)kill(-np->p_jobid, SIGCONT); 992 break; 993 } 994 while ((np = np->p_friends) != pp); 995 } 996 } 997 xexit(sig); 998 /* NOTREACHED */ 999 } 1000 1001 Char *jobargv[2] = {STRjobs, 0}; 1002 1003 /* 1004 * Catch an interrupt, e.g. during lexical input. 1005 * If we are an interactive shell, we reset the interrupt catch 1006 * immediately. In any case we drain the shell output, 1007 * and finally go through the normal error mechanism, which 1008 * gets a chance to make the shell go away. 1009 */ 1010 /* ARGSUSED */ 1011 void 1012 pintr(int notused) 1013 { 1014 pintr1(1); 1015 /* NOTREACHED */ 1016 } 1017 1018 void 1019 pintr1(int wantnl) 1020 { 1021 Char **v; 1022 sigset_t nsigset, osigset; 1023 1024 sigemptyset(&nsigset); 1025 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 1026 if (setintr) { 1027 nsigset = osigset; 1028 (void)sigdelset(&nsigset, SIGINT); 1029 (void)sigprocmask(SIG_SETMASK, &nsigset, NULL); 1030 if (pjobs) { 1031 pjobs = 0; 1032 (void)fprintf(cshout, "\n"); 1033 dojobs(jobargv, NULL); 1034 stderror(ERR_NAME | ERR_INTR); 1035 } 1036 } 1037 (void)sigdelset(&osigset, SIGCHLD); 1038 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 1039 (void)fpurge(cshout); 1040 (void)endpwent(); 1041 1042 /* 1043 * If we have an active "onintr" then we search for the label. Note that if 1044 * one does "onintr -" then we shan't be interruptible so we needn't worry 1045 * about that here. 1046 */ 1047 if (gointr) { 1048 gotolab(gointr); 1049 timflg = 0; 1050 if ((v = pargv) != NULL) 1051 pargv = 0, blkfree(v); 1052 if ((v = gargv) != NULL) 1053 gargv = 0, blkfree(v); 1054 reset(); 1055 } 1056 else if (intty && wantnl) { 1057 (void)fputc('\r', cshout); 1058 (void)fputc('\n', cshout); 1059 } 1060 stderror(ERR_SILENT); 1061 /* NOTREACHED */ 1062 } 1063 1064 /* 1065 * Process is the main driving routine for the shell. 1066 * It runs all command processing, except for those within { ... } 1067 * in expressions (which is run by a routine evalav in sh.exp.c which 1068 * is a stripped down process), and `...` evaluation which is run 1069 * also by a subset of this code in sh.glob.c in the routine backeval. 1070 * 1071 * The code here is a little strange because part of it is interruptible 1072 * and hence freeing of structures appears to occur when none is necessary 1073 * if this is ignored. 1074 * 1075 * Note that if catch is not set then we will unwind on any error. 1076 * If an end-of-file occurs, we return. 1077 */ 1078 static struct command *savet = NULL; 1079 1080 void 1081 process(int catch) 1082 { 1083 struct command *t; 1084 jmp_buf osetexit; 1085 sigset_t nsigset; 1086 1087 t = savet; 1088 savet = NULL; 1089 getexit(osetexit); 1090 for (;;) { 1091 pendjob(); 1092 paraml.next = paraml.prev = ¶ml; 1093 paraml.word = STRNULL; 1094 (void)setexit(); 1095 justpr = enterhist; /* execute if not entering history */ 1096 1097 /* 1098 * Interruptible during interactive reads 1099 */ 1100 if (setintr) { 1101 sigemptyset(&nsigset); 1102 (void)sigaddset(&nsigset, SIGINT); 1103 (void)sigprocmask(SIG_UNBLOCK, &nsigset, NULL); 1104 } 1105 1106 /* 1107 * For the sake of reset() 1108 */ 1109 freelex(¶ml); 1110 if (savet) 1111 freesyn(savet), savet = NULL; 1112 1113 if (haderr) { 1114 if (!catch) { 1115 /* unwind */ 1116 doneinp = 0; 1117 resexit(osetexit); 1118 savet = t; 1119 reset(); 1120 } 1121 haderr = 0; 1122 /* 1123 * Every error is eventually caught here or the shell dies. It is 1124 * at this point that we clean up any left-over open files, by 1125 * closing all but a fixed number of pre-defined files. Thus 1126 * routines don't have to worry about leaving files open due to 1127 * deeper errors... they will get closed here. 1128 */ 1129 closem(); 1130 continue; 1131 } 1132 if (doneinp) { 1133 doneinp = 0; 1134 break; 1135 } 1136 if (chkstop) 1137 chkstop--; 1138 if (neednote) 1139 pnote(); 1140 if (intty && prompt && evalvec == 0) { 1141 mailchk(); 1142 #ifdef EDIT 1143 updateediting(); 1144 #endif 1145 /* 1146 * If we are at the end of the input buffer then we are going to 1147 * read fresh stuff. Otherwise, we are rereading input and don't 1148 * need or want to prompt. 1149 */ 1150 if (aret == F_SEEK && fseekp == feobp) 1151 printprompt(); 1152 (void)fflush(cshout); 1153 } 1154 if (seterr) { 1155 free(seterr); 1156 seterr = NULL; 1157 } 1158 1159 1160 /* 1161 * Echo not only on VERBOSE, but also with history expansion. If there 1162 * is a lexical error then we forego history echo. 1163 */ 1164 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1165 int odidfds = didfds; 1166 fflush(csherr); 1167 didfds = 0; 1168 prlex(csherr, ¶ml); 1169 fflush(csherr); 1170 didfds = odidfds; 1171 } 1172 1173 /* 1174 * The parser may lose space if interrupted. 1175 */ 1176 if (setintr) 1177 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 1178 1179 /* 1180 * Save input text on the history list if reading in old history, or it 1181 * is from the terminal at the top level and not in a loop. 1182 * 1183 * PWP: entry of items in the history list while in a while loop is done 1184 * elsewhere... 1185 */ 1186 if (enterhist || (catch && intty && !whyles)) 1187 savehist(¶ml); 1188 1189 /* 1190 * Print lexical error messages, except when sourcing history lists. 1191 */ 1192 if (!enterhist && seterr) 1193 stderror(ERR_OLD); 1194 1195 /* 1196 * If had a history command :p modifier then this is as far as we 1197 * should go 1198 */ 1199 if (justpr) 1200 reset(); 1201 1202 alias(¶ml); 1203 1204 /* 1205 * Parse the words of the input into a parse tree. 1206 */ 1207 savet = syntax(paraml.next, ¶ml, 0); 1208 if (seterr) 1209 stderror(ERR_OLD); 1210 1211 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1212 1213 /* 1214 * Made it! 1215 */ 1216 freelex(¶ml); 1217 freesyn(savet), savet = NULL; 1218 } 1219 resexit(osetexit); 1220 savet = t; 1221 } 1222 1223 void 1224 /*ARGSUSED*/ 1225 dosource(Char **v, struct command *t) 1226 { 1227 Char buf[BUFSIZE], *f; 1228 int hflg; 1229 1230 hflg = 0; 1231 v++; 1232 if (*v && eq(*v, STRmh)) { 1233 if (*++v == NULL) 1234 stderror(ERR_NAME | ERR_HFLAG); 1235 hflg++; 1236 } 1237 (void)Strcpy(buf, *v); 1238 f = globone(buf, G_ERROR); 1239 (void)strcpy((char *)buf, short2str(f)); 1240 free(f); 1241 if (!srcfile((char *)buf, 0, hflg) && !hflg) 1242 stderror(ERR_SYSTEM, (char *)buf, strerror(errno)); 1243 } 1244 1245 /* 1246 * Check for mail. 1247 * If we are a login shell, then we don't want to tell 1248 * about any mail file unless its been modified 1249 * after the time we started. 1250 * This prevents us from telling the user things he already 1251 * knows, since the login program insists on saying 1252 * "You have mail." 1253 */ 1254 static void 1255 mailchk(void) 1256 { 1257 struct stat stb; 1258 struct varent *v; 1259 Char **vp; 1260 time_t t; 1261 int cnt, intvl; 1262 int new; 1263 1264 v = adrof(STRmail); 1265 if (v == 0) 1266 return; 1267 (void)time(&t); 1268 vp = v->vec; 1269 cnt = blklen(vp); 1270 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1271 if (intvl < 1) 1272 intvl = 1; 1273 if (chktim + intvl > t) 1274 return; 1275 for (; *vp; vp++) { 1276 if (stat(short2str(*vp), &stb) < 0) 1277 continue; 1278 new = stb.st_mtime > time0.tv_sec; 1279 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1280 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1281 (loginsh && !new)) 1282 continue; 1283 if (cnt == 1) 1284 (void)fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1285 else 1286 (void)fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1287 vis_str(*vp)); 1288 } 1289 chktim = t; 1290 } 1291 1292 /* 1293 * Extract a home directory from the password file 1294 * The argument points to a buffer where the name of the 1295 * user whose home directory is sought is currently. 1296 * We write the home directory of the user back there. 1297 */ 1298 int 1299 gethdir(Char *home) 1300 { 1301 struct passwd *pw; 1302 Char *h; 1303 1304 /* 1305 * Is it us? 1306 */ 1307 if (*home == '\0') { 1308 if ((h = value(STRhome)) != NULL) { 1309 (void)Strcpy(home, h); 1310 return 0; 1311 } 1312 else 1313 return 1; 1314 } 1315 1316 if ((pw = getpwnam(short2str(home))) != NULL) { 1317 (void)Strcpy(home, str2short(pw->pw_dir)); 1318 return 0; 1319 } 1320 else 1321 return 1; 1322 } 1323 1324 /* 1325 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1326 * We also check if the shell has already changed the descriptor to point to 1327 * 0, 1, 2 when didfds is set. 1328 */ 1329 #define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1330 1331 static ssize_t 1332 readf(void *oreo, void *buf, size_t siz) 1333 { 1334 return read(DESC(oreo), buf, siz); 1335 } 1336 1337 1338 static ssize_t 1339 writef(void *oreo, const void *buf, size_t siz) 1340 { 1341 return write(DESC(oreo), buf, siz); 1342 } 1343 1344 static off_t 1345 seekf(void *oreo, off_t off, int whence) 1346 { 1347 return lseek(DESC(oreo), off, whence); 1348 } 1349 1350 1351 static int 1352 closef(void *oreo) 1353 { 1354 return close(DESC(oreo)); 1355 } 1356 1357 1358 /* 1359 * Print the visible version of a string. 1360 */ 1361 int 1362 vis_fputc(int ch, FILE *fp) 1363 { 1364 char uenc[5]; /* 4 + NULL */ 1365 1366 if (ch & QUOTE) 1367 return fputc(ch & TRIM, fp); 1368 /* 1369 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1370 * be encoded, but currently there is no way in vis to do that. 1371 */ 1372 (void)vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1373 return (fputs(uenc, fp)); 1374 } 1375 1376 /* 1377 * Move the initial descriptors to their eventual 1378 * resting places, closing all other units. 1379 */ 1380 void 1381 initdesc(void) 1382 { 1383 didfds = 0; /* 0, 1, 2 aren't set up */ 1384 (void)ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1385 (void)ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1386 (void)ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1387 (void)ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1388 closem(); 1389 } 1390 1391 1392 __dead void 1393 #ifdef PROF 1394 done(int i) 1395 #else 1396 xexit(int i) 1397 #endif 1398 { 1399 untty(); 1400 _exit(i); 1401 /* NOTREACHED */ 1402 } 1403 1404 #ifndef _PATH_DEFPATH 1405 static Char ** 1406 defaultpath(void) 1407 { 1408 struct stat stb; 1409 Char **blk, **blkp; 1410 char *ptr; 1411 1412 blkp = blk = xmalloc((size_t) sizeof(Char *) * 10); 1413 1414 #define DIRAPPEND(a) \ 1415 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1416 *blkp++ = SAVE(ptr) 1417 #ifdef RESCUEDIR 1418 DIRAPPEND(RESCUEDIR); 1419 #endif 1420 DIRAPPEND(_PATH_BIN); 1421 DIRAPPEND(_PATH_USRBIN); 1422 1423 #undef DIRAPPEND 1424 1425 #if 0 1426 if (euid != 0 && uid != 0) 1427 *blkp++ = Strsave(STRdot); 1428 #endif 1429 1430 *blkp = NULL; 1431 return (blk); 1432 } 1433 #endif /* _PATH_DEFPATH */ 1434 1435 void 1436 printprompt(void) 1437 { 1438 Char *cp; 1439 1440 if (editing) 1441 return; 1442 1443 if (!whyles) { 1444 for (cp = value(STRprompt); *cp; cp++) 1445 if (*cp == HIST) 1446 (void)fprintf(cshout, "%d", eventno + 1); 1447 else { 1448 if (*cp == '\\' && cp[1] == HIST) 1449 cp++; 1450 (void)vis_fputc(*cp | QUOTE, cshout); 1451 } 1452 } 1453 else 1454 /* 1455 * Prompt for forward reading loop body content. 1456 */ 1457 (void)fprintf(cshout, "? "); 1458 (void)fflush(cshout); 1459 } 1460 1461 #ifdef EDIT 1462 char * 1463 printpromptstr(EditLine *elx) { 1464 static char pbuf[1024]; 1465 static char qspace[] = "? "; 1466 Char *cp; 1467 size_t i; 1468 1469 if (whyles) 1470 return qspace; 1471 1472 i = 0; 1473 for (cp = value(STRprompt); *cp; cp++) { 1474 if (i >= sizeof(pbuf)) 1475 break; 1476 if (*cp == HIST) { 1477 int r; 1478 r = snprintf(pbuf + i, sizeof(pbuf) - i, "%d", eventno + 1); 1479 if (r > 0) 1480 i += (size_t)r; 1481 } else 1482 pbuf[i++] = (char)*cp; 1483 } 1484 if (i >= sizeof(pbuf)) 1485 i = sizeof(pbuf) - 1; 1486 pbuf[i] = '\0'; 1487 return pbuf; 1488 } 1489 #endif 1490
Indexes created Sat Sep 20 22:09:52 GMT 2025