1 /* $NetBSD: csh.c,v 1.30 2002/05/25 23:29:16 wiz 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 #include <sys/cdefs.h> 37 #ifndef lint 38 __COPYRIGHT("@(#) 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 __RCSID("$NetBSD: csh.c,v 1.30 2002/05/25 23:29:16 wiz Exp $"); 47 #endif 48 #endif /* not lint */ 49 50 #include <sys/types.h> 51 #include <sys/ioctl.h> 52 #include <sys/stat.h> 53 54 #include <errno.h> 55 #include <fcntl.h> 56 #include <locale.h> 57 #include <paths.h> /* should this be included in pathnames.h instead? */ 58 #include <pwd.h> 59 #include <stdarg.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <time.h> 63 #include <unistd.h> 64 #include <vis.h> 65 66 #include "csh.h" 67 #include "extern.h" 68 #include "pathnames.h" 69 #include "proc.h" 70 71 /* 72 * C Shell 73 * 74 * Bill Joy, UC Berkeley, California, USA 75 * October 1978, May 1980 76 * 77 * Jim Kulp, IIASA, Laxenburg, Austria 78 * April 1980 79 * 80 * Christos Zoulas, Cornell University 81 * June, 1991 82 */ 83 84 Char *dumphist[] = {STRhistory, STRmh, 0, 0}; 85 Char *loadhist[] = {STRsource, STRmh, STRtildothist, 0}; 86 87 int nofile = 0; 88 bool batch = 0; 89 bool enterhist = 0; 90 bool fast = 0; 91 bool mflag = 0; 92 bool nexececho = 0; 93 bool nverbose = 0; 94 bool prompt = 1; 95 bool quitit = 0; 96 bool reenter = 0; 97 98 extern char **environ; 99 100 static int readf(void *, char *, int); 101 static fpos_t seekf(void *, fpos_t, int); 102 static int writef(void *, const char *, int); 103 static int closef(void *); 104 static int srccat(Char *, Char *); 105 static int srcfile(char *, bool, bool); 106 static void phup(int); 107 static void srcunit(int, bool, bool); 108 static void mailchk(void); 109 #ifndef _PATH_DEFPATH 110 static Char **defaultpath(void); 111 #endif 112 113 int main(int, char *[]); 114 115 int 116 main(int argc, char *argv[]) 117 { 118 struct sigaction oact; 119 Char *cp; 120 char *tcp, **tempv; 121 const char *ecp; 122 sigset_t sigset; 123 int f; 124 125 cshin = stdin; 126 cshout = stdout; 127 csherr = stderr; 128 129 setprogname(argv[0]); 130 settimes(); /* Immed. estab. timing base */ 131 132 /* 133 * Initialize non constant strings 134 */ 135 #ifdef _PATH_BSHELL 136 STR_BSHELL = SAVE(_PATH_BSHELL); 137 #endif 138 #ifdef _PATH_CSHELL 139 STR_SHELLPATH = SAVE(_PATH_CSHELL); 140 #endif 141 STR_environ = blk2short(environ); 142 environ = short2blk(STR_environ); /* So that we can free it */ 143 STR_WORD_CHARS = SAVE(WORD_CHARS); 144 145 HIST = '!'; 146 HISTSUB = '^'; 147 word_chars = STR_WORD_CHARS; 148 149 tempv = argv; 150 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 151 quitit = 1; 152 uid = getuid(); 153 gid = getgid(); 154 euid = geteuid(); 155 egid = getegid(); 156 /* 157 * We are a login shell if: 1. we were invoked as -<something> and we had 158 * no arguments 2. or we were invoked only with the -l flag 159 */ 160 loginsh = (**tempv == '-' && argc == 1) || 161 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 162 tempv[1][2] == '\0'); 163 164 if (loginsh && **tempv != '-') { 165 /* 166 * Mangle the argv space 167 */ 168 tempv[1][0] = '\0'; 169 tempv[1][1] = '\0'; 170 tempv[1] = NULL; 171 for (tcp = *tempv; *tcp++;) 172 continue; 173 for (tcp--; tcp >= *tempv; tcp--) 174 tcp[1] = tcp[0]; 175 *++tcp = '-'; 176 argc--; 177 } 178 if (loginsh) 179 (void)time(&chktim); 180 181 AsciiOnly = 1; 182 #ifdef NLS 183 (void)setlocale(LC_ALL, ""); 184 { 185 int k; 186 187 for (k = 0200; k <= 0377 && !Isprint(k); k++) 188 continue; 189 AsciiOnly = k > 0377; 190 } 191 #else 192 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 193 #endif /* NLS */ 194 195 /* 196 * Move the descriptors to safe places. The variable didfds is 0 while we 197 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 198 * prefer to use these. 199 */ 200 initdesc(); 201 /* 202 * XXX: This is to keep programs that use stdio happy. 203 * what we really want is freunopen() .... 204 * Closing cshin cshout and csherr (which are really stdin stdout 205 * and stderr at this point and then reopening them in the same order 206 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 207 * If that was not the case builtins like printf that use stdio 208 * would break. But in any case we could fix that with memcpy and 209 * a bit of pointer manipulation... 210 * Fortunately this is not needed under the current implementation 211 * of stdio. 212 */ 213 (void)fclose(cshin); 214 (void)fclose(cshout); 215 (void)fclose(csherr); 216 if (!(cshin = funopen((void *) &SHIN, readf, writef, seekf, closef))) 217 exit(1); 218 if (!(cshout = funopen((void *) &SHOUT, readf, writef, seekf, closef))) 219 exit(1); 220 if (!(csherr = funopen((void *) &SHERR, readf, writef, seekf, closef))) 221 exit(1); 222 (void)setvbuf(cshin, NULL, _IOLBF, 0); 223 (void)setvbuf(cshout, NULL, _IOLBF, 0); 224 (void)setvbuf(csherr, NULL, _IOLBF, 0); 225 226 /* 227 * Initialize the shell variables. ARGV and PROMPT are initialized later. 228 * STATUS is also munged in several places. CHILD is munged when 229 * forking/waiting 230 */ 231 set(STRstatus, Strsave(STR0)); 232 233 if ((ecp = getenv("HOME")) != NULL) 234 cp = quote(SAVE(ecp)); 235 else 236 cp = NULL; 237 238 if (cp == NULL) 239 fast = 1; /* No home -> can't read scripts */ 240 else 241 set(STRhome, cp); 242 dinit(cp); /* dinit thinks that HOME == cwd in a login 243 * shell */ 244 /* 245 * Grab other useful things from the environment. Should we grab 246 * everything?? 247 */ 248 if ((ecp = getenv("LOGNAME")) != NULL || 249 (ecp = getenv("USER")) != NULL) 250 set(STRuser, quote(SAVE(ecp))); 251 if ((ecp = getenv("TERM")) != NULL) 252 set(STRterm, quote(SAVE(ecp))); 253 254 /* 255 * Re-initialize path if set in environment 256 */ 257 if ((ecp = getenv("PATH")) == NULL) { 258 #ifdef _PATH_DEFPATH 259 importpath(str2short(_PATH_DEFPATH)); 260 #else 261 setq(STRpath, defaultpath(), &shvhed); 262 #endif 263 } else { 264 importpath(str2short(ecp)); 265 } 266 267 set(STRshell, Strsave(STR_SHELLPATH)); 268 269 doldol = putn((int) getpid()); /* For $$ */ 270 shtemp = Strspl(STRtmpsh, doldol); /* For << */ 271 272 /* 273 * Record the interrupt states from the parent process. If the parent is 274 * non-interruptible our hand must be forced or we (and our children) won't 275 * be either. Our children inherit termination from our parent. We catch it 276 * only if we are the login shell. 277 */ 278 /* parents interruptibility */ 279 (void)sigaction(SIGINT, NULL, &oact); 280 parintr = oact.sa_handler; 281 (void)sigaction(SIGTERM, NULL, &oact); 282 parterm = oact.sa_handler; 283 284 /* catch these all, login shell or not */ 285 (void)signal(SIGHUP, phup); /* exit processing on HUP */ 286 (void)signal(SIGXCPU, phup); /* ...and on XCPU */ 287 (void)signal(SIGXFSZ, phup); /* ...and on XFSZ */ 288 289 /* 290 * Process the arguments. 291 * 292 * Note that processing of -v/-x is actually delayed till after script 293 * processing. 294 * 295 * We set the first character of our name to be '-' if we are a shell 296 * running interruptible commands. Many programs which examine ps'es 297 * use this to filter such shells out. 298 */ 299 argc--, tempv++; 300 while (argc > 0 && (tcp = tempv[0])[0] == '-' && *++tcp != '\0' && !batch) { 301 do 302 switch (*tcp++) { 303 case 0: /* - Interruptible, no prompt */ 304 prompt = 0; 305 setintr = 1; 306 nofile = 1; 307 break; 308 case 'b': /* -b Next arg is input file */ 309 batch = 1; 310 break; 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 case 'e': /* -e Exit on any error */ 320 exiterr = 1; 321 break; 322 case 'f': /* -f Fast start */ 323 fast = 1; 324 break; 325 case 'i': /* -i Interactive, even if !intty */ 326 intact = 1; 327 nofile = 1; 328 break; 329 case 'm': /* -m read .cshrc (from su) */ 330 mflag = 1; 331 break; 332 case 'n': /* -n Don't execute */ 333 noexec = 1; 334 break; 335 case 'q': /* -q (Undoc'd) ... die on quit */ 336 quitit = 1; 337 break; 338 case 's': /* -s Read from std input */ 339 nofile = 1; 340 break; 341 case 't': /* -t Read one line from input */ 342 onelflg = 2; 343 prompt = 0; 344 nofile = 1; 345 break; 346 case 'v': /* -v Echo hist expanded input */ 347 nverbose = 1; /* ... later */ 348 break; 349 case 'x': /* -x Echo just before execution */ 350 nexececho = 1; /* ... later */ 351 break; 352 case 'V': /* -V Echo hist expanded input */ 353 setNS(STRverbose); /* NOW! */ 354 break; 355 case 'X': /* -X Echo just before execution */ 356 setNS(STRecho); /* NOW! */ 357 break; 358 359 } while (*tcp); 360 tempv++, argc--; 361 } 362 363 if (quitit) /* With all due haste, for debugging */ 364 (void)signal(SIGQUIT, SIG_DFL); 365 366 /* 367 * Unless prevented by -, -c, -i, -s, or -t, if there are remaining 368 * arguments the first of them is the name of a shell file from which to 369 * read commands. 370 */ 371 if (nofile == 0 && argc > 0) { 372 nofile = open(tempv[0], O_RDONLY); 373 if (nofile < 0) { 374 child = 1; /* So this doesn't return */ 375 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 376 } 377 ffile = SAVE(tempv[0]); 378 /* 379 * Replace FSHIN. Handle /dev/std{in,out,err} specially 380 * since once they are closed we cannot open them again. 381 * In that case we use our own saved descriptors 382 */ 383 if ((SHIN = dmove(nofile, FSHIN)) < 0) 384 switch(nofile) { 385 case 0: 386 SHIN = FSHIN; 387 break; 388 case 1: 389 SHIN = FSHOUT; 390 break; 391 case 2: 392 SHIN = FSHERR; 393 break; 394 default: 395 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 396 /* NOTREACHED */ 397 } 398 (void)ioctl(SHIN, FIOCLEX, NULL); 399 prompt = 0; 400 /* argc not used any more */ tempv++; 401 } 402 403 intty = isatty(SHIN); 404 intty |= intact; 405 if (intty || (intact && isatty(SHOUT))) { 406 if (!batch && (uid != euid || gid != egid)) { 407 errno = EACCES; 408 child = 1; /* So this doesn't return */ 409 stderror(ERR_SYSTEM, "csh", strerror(errno)); 410 } 411 } 412 /* 413 * Decide whether we should play with signals or not. If we are explicitly 414 * told (via -i, or -) or we are a login shell (arg0 starts with -) or the 415 * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx") 416 * Note that in only the login shell is it likely that parent may have set 417 * signals to be ignored 418 */ 419 if (loginsh || intact || (intty && isatty(SHOUT))) 420 setintr = 1; 421 settell(); 422 /* 423 * Save the remaining arguments in argv. 424 */ 425 setq(STRargv, blk2short(tempv), &shvhed); 426 427 /* 428 * Set up the prompt. 429 */ 430 if (prompt) { 431 set(STRprompt, Strsave(uid == 0 ? STRsymhash : STRsymcent)); 432 /* that's a meta-questionmark */ 433 set(STRprompt2, Strsave(STRmquestion)); 434 } 435 436 /* 437 * If we are an interactive shell, then start fiddling with the signals; 438 * this is a tricky game. 439 */ 440 shpgrp = getpgrp(); 441 opgrp = tpgrp = -1; 442 if (setintr) { 443 **argv = '-'; 444 if (!quitit) /* Wary! */ 445 (void)signal(SIGQUIT, SIG_IGN); 446 (void)signal(SIGINT, pintr); 447 sigemptyset(&sigset); 448 (void)sigaddset(&sigset, SIGINT); 449 (void)sigprocmask(SIG_BLOCK, &sigset, NULL); 450 (void)signal(SIGTERM, SIG_IGN); 451 if (quitit == 0 && arginp == 0) { 452 (void)signal(SIGTSTP, SIG_IGN); 453 (void)signal(SIGTTIN, SIG_IGN); 454 (void)signal(SIGTTOU, SIG_IGN); 455 /* 456 * Wait till in foreground, in case someone stupidly runs csh & 457 * dont want to try to grab away the tty. 458 */ 459 if (isatty(FSHERR)) 460 f = FSHERR; 461 else if (isatty(FSHOUT)) 462 f = FSHOUT; 463 else if (isatty(OLDSTD)) 464 f = OLDSTD; 465 else 466 f = -1; 467 retry: 468 if ((tpgrp = tcgetpgrp(f)) != -1) { 469 if (tpgrp != shpgrp) { 470 sig_t old = signal(SIGTTIN, SIG_DFL); 471 (void)kill(0, SIGTTIN); 472 (void)signal(SIGTTIN, old); 473 goto retry; 474 } 475 opgrp = shpgrp; 476 shpgrp = getpid(); 477 tpgrp = shpgrp; 478 /* 479 * Setpgid will fail if we are a session leader and 480 * mypid == mypgrp (POSIX 4.3.3) 481 */ 482 if (opgrp != shpgrp) 483 if (setpgid(0, shpgrp) == -1) 484 goto notty; 485 /* 486 * We do that after we set our process group, to make sure 487 * that the process group belongs to a process in the same 488 * session as the tty (our process and our group) (POSIX 7.2.4) 489 */ 490 if (tcsetpgrp(f, shpgrp) == -1) 491 goto notty; 492 (void)ioctl(dcopy(f, FSHTTY), FIOCLEX, NULL); 493 } 494 if (tpgrp == -1) { 495 notty: 496 (void)fprintf(csherr, "Warning: no access to tty (%s).\n", 497 strerror(errno)); 498 (void)fprintf(csherr, "Thus no job control in this shell.\n"); 499 } 500 } 501 } 502 if ((setintr == 0) && (parintr == SIG_DFL)) 503 setintr = 1; 504 (void)signal(SIGCHLD, pchild); /* while signals not ready */ 505 506 /* 507 * Set an exit here in case of an interrupt or error reading the shell 508 * start-up scripts. 509 */ 510 reenter = setexit(); /* PWP */ 511 haderr = 0; /* In case second time through */ 512 if (!fast && reenter == 0) { 513 /* Will have value(STRhome) here because set fast if don't */ 514 { 515 sig_t oparintr; 516 sigset_t osigset; 517 int osetintr; 518 519 oparintr = parintr; 520 osetintr = setintr; 521 sigemptyset(&sigset); 522 (void)sigaddset(&sigset, SIGINT); 523 (void)sigprocmask(SIG_BLOCK, &sigset, &osigset); 524 525 setintr = 0; 526 parintr = SIG_IGN; /* Disable onintr */ 527 #ifdef _PATH_DOTCSHRC 528 (void)srcfile(_PATH_DOTCSHRC, 0, 0); 529 #endif 530 if (!fast && !arginp && !onelflg) 531 dohash(NULL, NULL); 532 #ifdef _PATH_DOTLOGIN 533 if (loginsh) 534 (void)srcfile(_PATH_DOTLOGIN, 0, 0); 535 #endif 536 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 537 setintr = osetintr; 538 parintr = oparintr; 539 } 540 (void)srccat(value(STRhome), STRsldotcshrc); 541 542 if (!fast && !arginp && !onelflg && !havhash) 543 dohash(NULL, NULL); 544 /* 545 * Source history before .login so that it is available in .login 546 */ 547 if ((cp = value(STRhistfile)) != STRNULL) 548 loadhist[2] = cp; 549 dosource(loadhist, NULL); 550 if (loginsh) 551 (void)srccat(value(STRhome), STRsldotlogin); 552 } 553 554 /* 555 * Now are ready for the -v and -x flags 556 */ 557 if (nverbose) 558 setNS(STRverbose); 559 if (nexececho) 560 setNS(STRecho); 561 562 /* 563 * All the rest of the world is inside this call. The argument to process 564 * indicates whether it should catch "error unwinds". Thus if we are a 565 * interactive shell our call here will never return by being blown past on 566 * an error. 567 */ 568 process(setintr); 569 570 /* 571 * Mop-up. 572 */ 573 if (intty) { 574 if (loginsh) { 575 (void)fprintf(cshout, "logout\n"); 576 (void)close(SHIN); 577 child = 1; 578 goodbye(); 579 } 580 else { 581 (void)fprintf(cshout, "exit\n"); 582 } 583 } 584 rechist(); 585 exitstat(); 586 /* NOTREACHED */ 587 } 588 589 void 590 untty(void) 591 { 592 if (tpgrp > 0) { 593 (void)setpgid(0, opgrp); 594 (void)tcsetpgrp(FSHTTY, opgrp); 595 } 596 } 597 598 void 599 importpath(Char *cp) 600 { 601 Char *dp, **pv; 602 int c, i; 603 604 i = 0; 605 for (dp = cp; *dp; dp++) 606 if (*dp == ':') 607 i++; 608 /* 609 * i+2 where i is the number of colons in the path. There are i+1 610 * directories in the path plus we need room for a zero terminator. 611 */ 612 pv = (Char **)xcalloc((size_t) (i + 2), sizeof(Char **)); 613 dp = cp; 614 i = 0; 615 if (*dp) 616 for (;;) { 617 if ((c = *dp) == ':' || c == 0) { 618 *dp = 0; 619 pv[i++] = Strsave(*cp ? cp : STRdot); 620 if (c) { 621 cp = dp + 1; 622 *dp = ':'; 623 } 624 else 625 break; 626 } 627 dp++; 628 } 629 pv[i] = 0; 630 setq(STRpath, pv, &shvhed); 631 } 632 633 /* 634 * Source to the file which is the catenation of the argument names. 635 */ 636 static int 637 srccat(Char *cp, Char *dp) 638 { 639 Char *ep; 640 char *ptr; 641 642 ep = Strspl(cp, dp); 643 ptr = short2str(ep); 644 xfree((ptr_t) ep); 645 return srcfile(ptr, mflag ? 0 : 1, 0); 646 } 647 648 /* 649 * Source to a file putting the file descriptor in a safe place (> 2). 650 */ 651 static int 652 srcfile(char *f, bool onlyown, bool flag) 653 { 654 int unit; 655 656 if ((unit = open(f, O_RDONLY)) == -1) 657 return 0; 658 unit = dmove(unit, -1); 659 660 (void) ioctl(unit, FIOCLEX, NULL); 661 srcunit(unit, onlyown, flag); 662 return 1; 663 } 664 665 /* 666 * Source to a unit. If onlyown it must be our file or our group or 667 * we don't chance it. This occurs on ".cshrc"s and the like. 668 */ 669 int insource; 670 671 static void 672 srcunit(int unit, bool onlyown, bool hflg) 673 { 674 /* We have to push down a lot of state here */ 675 /* All this could go into a structure */ 676 struct whyle *oldwhyl; 677 struct Bin saveB; 678 sigset_t sigset, osigset; 679 jmp_buf oldexit; 680 Char *oarginp, *oevalp, **oevalvec, *ogointr; 681 char OHIST; 682 int oSHIN, oinsource, oldintty, oonelflg; 683 bool oenterhist, otell; 684 /* The (few) real local variables */ 685 int my_reenter; 686 687 oSHIN = -1; 688 oldintty = intty; 689 oinsource = insource; 690 oldwhyl = whyles; 691 ogointr = gointr; 692 oarginp = arginp; 693 oevalp = evalp; 694 oevalvec = evalvec; 695 oonelflg = onelflg; 696 oenterhist = enterhist; 697 OHIST = HIST; 698 otell = cantell; 699 700 if (unit < 0) 701 return; 702 if (didfds) 703 donefds(); 704 if (onlyown) { 705 struct stat stb; 706 707 if (fstat(unit, &stb) < 0) { 708 (void)close(unit); 709 return; 710 } 711 } 712 713 /* 714 * There is a critical section here while we are pushing down the input 715 * stream since we have stuff in different structures. If we weren't 716 * careful an interrupt could corrupt SHIN's Bin structure and kill the 717 * shell. 718 * 719 * We could avoid the critical region by grouping all the stuff in a single 720 * structure and pointing at it to move it all at once. This is less 721 * efficient globally on many variable references however. 722 */ 723 insource = 1; 724 getexit(oldexit); 725 726 if (setintr) { 727 sigemptyset(&sigset); 728 (void)sigaddset(&sigset, SIGINT); 729 (void)sigprocmask(SIG_BLOCK, &sigset, &osigset); 730 } 731 /* Setup the new values of the state stuff saved above */ 732 (void)memcpy(&saveB, &B, sizeof(B)); 733 fbuf = NULL; 734 fseekp = feobp = fblocks = 0; 735 oSHIN = SHIN, SHIN = unit, arginp = 0, onelflg = 0; 736 intty = isatty(SHIN), whyles = 0, gointr = 0; 737 evalvec = 0; 738 evalp = 0; 739 enterhist = hflg; 740 if (enterhist) 741 HIST = '\0'; 742 743 /* 744 * Now if we are allowing commands to be interrupted, we let ourselves be 745 * interrupted. 746 */ 747 if (setintr) 748 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 749 settell(); 750 751 if ((my_reenter = setexit()) == 0) 752 process(0); /* 0 -> blow away on errors */ 753 754 if (setintr) 755 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 756 if (oSHIN >= 0) { 757 int i; 758 759 /* We made it to the new state... free up its storage */ 760 /* This code could get run twice but xfree doesn't care */ 761 for (i = 0; i < fblocks; i++) 762 xfree((ptr_t) fbuf[i]); 763 xfree((ptr_t) fbuf); 764 765 /* Reset input arena */ 766 (void)memcpy(&B, &saveB, sizeof(B)); 767 768 (void)close(SHIN), SHIN = oSHIN; 769 arginp = oarginp, onelflg = oonelflg; 770 evalp = oevalp, evalvec = oevalvec; 771 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 772 if (enterhist) 773 HIST = OHIST; 774 enterhist = oenterhist; 775 cantell = otell; 776 } 777 778 resexit(oldexit); 779 /* 780 * If process reset() (effectively an unwind) then we must also unwind. 781 */ 782 if (my_reenter) 783 stderror(ERR_SILENT); 784 insource = oinsource; 785 } 786 787 void 788 rechist(void) 789 { 790 Char buf[BUFSIZE], hbuf[BUFSIZE], *hfile; 791 int fp, ftmp, oldidfds; 792 struct varent *shist; 793 794 if (!fast) { 795 /* 796 * If $savehist is just set, we use the value of $history 797 * else we use the value in $savehist 798 */ 799 if ((shist = adrof(STRsavehist)) != NULL) { 800 if (shist->vec[0][0] != '\0') 801 (void)Strcpy(hbuf, shist->vec[0]); 802 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 803 (void)Strcpy(hbuf, shist->vec[0]); 804 else 805 return; 806 } 807 else 808 return; 809 810 if ((hfile = value(STRhistfile)) == STRNULL) { 811 hfile = Strcpy(buf, value(STRhome)); 812 (void) Strcat(buf, STRsldthist); 813 } 814 815 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 816 0600)) == -1) 817 return; 818 819 oldidfds = didfds; 820 didfds = 0; 821 ftmp = SHOUT; 822 SHOUT = fp; 823 dumphist[2] = hbuf; 824 dohist(dumphist, NULL); 825 SHOUT = ftmp; 826 (void)close(fp); 827 didfds = oldidfds; 828 } 829 } 830 831 void 832 goodbye(void) 833 { 834 rechist(); 835 836 if (loginsh) { 837 (void)signal(SIGQUIT, SIG_IGN); 838 (void)signal(SIGINT, SIG_IGN); 839 (void)signal(SIGTERM, SIG_IGN); 840 setintr = 0; /* No interrupts after "logout" */ 841 if (!(adrof(STRlogout))) 842 set(STRlogout, STRnormal); 843 #ifdef _PATH_DOTLOGOUT 844 (void)srcfile(_PATH_DOTLOGOUT, 0, 0); 845 #endif 846 if (adrof(STRhome)) 847 (void)srccat(value(STRhome), STRsldtlogout); 848 } 849 exitstat(); 850 /* NOTREACHED */ 851 } 852 853 __dead void 854 exitstat(void) 855 { 856 Char *s; 857 #ifdef PROF 858 monitor(0); 859 #endif 860 /* 861 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 862 * directly because we poke child here. Otherwise we might continue 863 * unwarrantedly (sic). 864 */ 865 child = 1; 866 s = value(STRstatus); 867 xexit(s ? getn(s) : 0); 868 /* NOTREACHED */ 869 } 870 871 /* 872 * in the event of a HUP we want to save the history 873 */ 874 static void 875 phup(int sig) 876 { 877 rechist(); 878 879 /* 880 * We kill the last foreground process group. It then becomes 881 * responsible to propagate the SIGHUP to its progeny. 882 */ 883 { 884 struct process *pp, *np; 885 886 for (pp = proclist.p_next; pp; pp = pp->p_next) { 887 np = pp; 888 /* 889 * Find if this job is in the foreground. It could be that 890 * the process leader has exited and the foreground flag 891 * is cleared for it. 892 */ 893 do 894 /* 895 * If a process is in the foreground; we try to kill 896 * it's process group. If we succeed, then the 897 * whole job is gone. Otherwise we keep going... 898 * But avoid sending HUP to the shell again. 899 */ 900 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 901 kill(-np->p_jobid, SIGHUP) != -1) { 902 /* In case the job was suspended... */ 903 (void)kill(-np->p_jobid, SIGCONT); 904 break; 905 } 906 while ((np = np->p_friends) != pp); 907 } 908 } 909 xexit(sig); 910 /* NOTREACHED */ 911 } 912 913 Char *jobargv[2] = {STRjobs, 0}; 914 915 /* 916 * Catch an interrupt, e.g. during lexical input. 917 * If we are an interactive shell, we reset the interrupt catch 918 * immediately. In any case we drain the shell output, 919 * and finally go through the normal error mechanism, which 920 * gets a chance to make the shell go away. 921 */ 922 /* ARGSUSED */ 923 void 924 pintr(int notused) 925 { 926 pintr1(1); 927 /* NOTREACHED */ 928 } 929 930 void 931 pintr1(bool wantnl) 932 { 933 Char **v; 934 sigset_t sigset, osigset; 935 936 sigemptyset(&sigset); 937 (void)sigprocmask(SIG_BLOCK, &sigset, &osigset); 938 if (setintr) { 939 sigset = osigset; 940 (void)sigdelset(&sigset, SIGINT); 941 (void)sigprocmask(SIG_SETMASK, &sigset, NULL); 942 if (pjobs) { 943 pjobs = 0; 944 (void)fprintf(cshout, "\n"); 945 dojobs(jobargv, NULL); 946 stderror(ERR_NAME | ERR_INTR); 947 } 948 } 949 (void)sigdelset(&osigset, SIGCHLD); 950 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 951 (void)fpurge(cshout); 952 (void)endpwent(); 953 954 /* 955 * If we have an active "onintr" then we search for the label. Note that if 956 * one does "onintr -" then we shan't be interruptible so we needn't worry 957 * about that here. 958 */ 959 if (gointr) { 960 gotolab(gointr); 961 timflg = 0; 962 if ((v = pargv) != NULL) 963 pargv = 0, blkfree(v); 964 if ((v = gargv) != NULL) 965 gargv = 0, blkfree(v); 966 reset(); 967 } 968 else if (intty && wantnl) { 969 (void)fputc('\r', cshout); 970 (void)fputc('\n', cshout); 971 } 972 stderror(ERR_SILENT); 973 /* NOTREACHED */ 974 } 975 976 /* 977 * Process is the main driving routine for the shell. 978 * It runs all command processing, except for those within { ... } 979 * in expressions (which is run by a routine evalav in sh.exp.c which 980 * is a stripped down process), and `...` evaluation which is run 981 * also by a subset of this code in sh.glob.c in the routine backeval. 982 * 983 * The code here is a little strange because part of it is interruptible 984 * and hence freeing of structures appears to occur when none is necessary 985 * if this is ignored. 986 * 987 * Note that if catch is not set then we will unwind on any error. 988 * If an end-of-file occurs, we return. 989 */ 990 static struct command *savet = NULL; 991 992 void 993 process(bool catch) 994 { 995 struct command *t; 996 jmp_buf osetexit; 997 sigset_t sigset; 998 999 t = savet; 1000 savet = NULL; 1001 getexit(osetexit); 1002 for (;;) { 1003 pendjob(); 1004 paraml.next = paraml.prev = ¶ml; 1005 paraml.word = STRNULL; 1006 (void)setexit(); 1007 justpr = enterhist; /* execute if not entering history */ 1008 1009 /* 1010 * Interruptible during interactive reads 1011 */ 1012 if (setintr) { 1013 sigemptyset(&sigset); 1014 (void)sigaddset(&sigset, SIGINT); 1015 (void)sigprocmask(SIG_UNBLOCK, &sigset, NULL); 1016 } 1017 1018 /* 1019 * For the sake of reset() 1020 */ 1021 freelex(¶ml); 1022 if (savet) 1023 freesyn(savet), savet = NULL; 1024 1025 if (haderr) { 1026 if (!catch) { 1027 /* unwind */ 1028 doneinp = 0; 1029 resexit(osetexit); 1030 savet = t; 1031 reset(); 1032 } 1033 haderr = 0; 1034 /* 1035 * Every error is eventually caught here or the shell dies. It is 1036 * at this point that we clean up any left-over open files, by 1037 * closing all but a fixed number of pre-defined files. Thus 1038 * routines don't have to worry about leaving files open due to 1039 * deeper errors... they will get closed here. 1040 */ 1041 closem(); 1042 continue; 1043 } 1044 if (doneinp) { 1045 doneinp = 0; 1046 break; 1047 } 1048 if (chkstop) 1049 chkstop--; 1050 if (neednote) 1051 pnote(); 1052 if (intty && prompt && evalvec == 0) { 1053 mailchk(); 1054 /* 1055 * If we are at the end of the input buffer then we are going to 1056 * read fresh stuff. Otherwise, we are rereading input and don't 1057 * need or want to prompt. 1058 */ 1059 if (aret == F_SEEK && fseekp == feobp) 1060 printprompt(); 1061 (void)fflush(cshout); 1062 } 1063 if (seterr) { 1064 xfree((ptr_t) seterr); 1065 seterr = NULL; 1066 } 1067 1068 /* 1069 * Echo not only on VERBOSE, but also with history expansion. If there 1070 * is a lexical error then we forego history echo. 1071 */ 1072 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1073 int odidfds = didfds; 1074 fflush(csherr); 1075 didfds = 0; 1076 prlex(csherr, ¶ml); 1077 fflush(csherr); 1078 didfds = odidfds; 1079 } 1080 1081 /* 1082 * The parser may lose space if interrupted. 1083 */ 1084 if (setintr) 1085 (void)sigprocmask(SIG_BLOCK, &sigset, NULL); 1086 1087 /* 1088 * Save input text on the history list if reading in old history, or it 1089 * is from the terminal at the top level and not in a loop. 1090 * 1091 * PWP: entry of items in the history list while in a while loop is done 1092 * elsewhere... 1093 */ 1094 if (enterhist || (catch && intty && !whyles)) 1095 savehist(¶ml); 1096 1097 /* 1098 * Print lexical error messages, except when sourcing history lists. 1099 */ 1100 if (!enterhist && seterr) 1101 stderror(ERR_OLD); 1102 1103 /* 1104 * If had a history command :p modifier then this is as far as we 1105 * should go 1106 */ 1107 if (justpr) 1108 reset(); 1109 1110 alias(¶ml); 1111 1112 /* 1113 * Parse the words of the input into a parse tree. 1114 */ 1115 savet = syntax(paraml.next, ¶ml, 0); 1116 if (seterr) 1117 stderror(ERR_OLD); 1118 1119 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1120 1121 /* 1122 * Made it! 1123 */ 1124 freelex(¶ml); 1125 freesyn((struct command *) savet), savet = NULL; 1126 } 1127 resexit(osetexit); 1128 savet = t; 1129 } 1130 1131 void 1132 /*ARGSUSED*/ 1133 dosource(Char **v, struct command *t) 1134 { 1135 Char buf[BUFSIZE], *f; 1136 bool hflg; 1137 1138 hflg = 0; 1139 v++; 1140 if (*v && eq(*v, STRmh)) { 1141 if (*++v == NULL) 1142 stderror(ERR_NAME | ERR_HFLAG); 1143 hflg++; 1144 } 1145 (void)Strcpy(buf, *v); 1146 f = globone(buf, G_ERROR); 1147 (void)strcpy((char *)buf, short2str(f)); 1148 xfree((ptr_t) f); 1149 if (!srcfile((char *)buf, 0, hflg) && !hflg) 1150 stderror(ERR_SYSTEM, (char *)buf, strerror(errno)); 1151 } 1152 1153 /* 1154 * Check for mail. 1155 * If we are a login shell, then we don't want to tell 1156 * about any mail file unless its been modified 1157 * after the time we started. 1158 * This prevents us from telling the user things he already 1159 * knows, since the login program insists on saying 1160 * "You have mail." 1161 */ 1162 static void 1163 mailchk(void) 1164 { 1165 struct stat stb; 1166 struct varent *v; 1167 Char **vp; 1168 time_t t; 1169 int cnt, intvl; 1170 bool new; 1171 1172 v = adrof(STRmail); 1173 if (v == 0) 1174 return; 1175 (void)time(&t); 1176 vp = v->vec; 1177 cnt = blklen(vp); 1178 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1179 if (intvl < 1) 1180 intvl = 1; 1181 if (chktim + intvl > t) 1182 return; 1183 for (; *vp; vp++) { 1184 if (stat(short2str(*vp), &stb) < 0) 1185 continue; 1186 new = stb.st_mtime > time0.tv_sec; 1187 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1188 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1189 (loginsh && !new)) 1190 continue; 1191 if (cnt == 1) 1192 (void)fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1193 else 1194 (void)fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1195 vis_str(*vp)); 1196 } 1197 chktim = t; 1198 } 1199 1200 /* 1201 * Extract a home directory from the password file 1202 * The argument points to a buffer where the name of the 1203 * user whose home directory is sought is currently. 1204 * We write the home directory of the user back there. 1205 */ 1206 int 1207 gethdir(Char *home) 1208 { 1209 struct passwd *pw; 1210 Char *h; 1211 1212 /* 1213 * Is it us? 1214 */ 1215 if (*home == '\0') { 1216 if ((h = value(STRhome)) != NULL) { 1217 (void)Strcpy(home, h); 1218 return 0; 1219 } 1220 else 1221 return 1; 1222 } 1223 1224 if ((pw = getpwnam(short2str(home))) != NULL) { 1225 (void)Strcpy(home, str2short(pw->pw_dir)); 1226 return 0; 1227 } 1228 else 1229 return 1; 1230 } 1231 1232 /* 1233 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1234 * We also check if the shell has already changed the decriptor to point to 1235 * 0, 1, 2 when didfds is set. 1236 */ 1237 #define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1238 1239 static int 1240 readf(void *oreo, char *buf, int siz) 1241 { 1242 return read(DESC(oreo), buf, siz); 1243 } 1244 1245 1246 static int 1247 writef(void *oreo, const char *buf, int siz) 1248 { 1249 return write(DESC(oreo), buf, siz); 1250 } 1251 1252 static fpos_t 1253 seekf(void *oreo, fpos_t off, int whence) 1254 { 1255 return lseek(DESC(oreo), off, whence); 1256 } 1257 1258 1259 static int 1260 closef(void *oreo) 1261 { 1262 return close(DESC(oreo)); 1263 } 1264 1265 1266 /* 1267 * Print the visible version of a string. 1268 */ 1269 int 1270 vis_fputc(int ch, FILE *fp) 1271 { 1272 char uenc[5]; /* 4 + NULL */ 1273 1274 if (ch & QUOTE) 1275 return fputc(ch & TRIM, fp); 1276 /* 1277 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1278 * be encoded, but currently there is no way in vis to do that. 1279 */ 1280 (void)vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1281 return (fputs(uenc, fp)); 1282 } 1283 1284 /* 1285 * Move the initial descriptors to their eventual 1286 * resting places, closin all other units. 1287 */ 1288 void 1289 initdesc(void) 1290 { 1291 didfds = 0; /* 0, 1, 2 aren't set up */ 1292 (void)ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1293 (void)ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1294 (void)ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1295 (void)ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1296 closem(); 1297 } 1298 1299 1300 __dead void 1301 #ifdef PROF 1302 done(int i) 1303 #else 1304 xexit(int i) 1305 #endif 1306 { 1307 untty(); 1308 _exit(i); 1309 /* NOTREACHED */ 1310 } 1311 1312 #ifndef _PATH_DEFPATH 1313 static Char ** 1314 defaultpath(void) 1315 { 1316 struct stat stb; 1317 Char **blk, **blkp; 1318 char *ptr; 1319 1320 blkp = blk = (Char **)xmalloc((size_t) sizeof(Char *) * 10); 1321 1322 #define DIRAPPEND(a) \ 1323 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1324 *blkp++ = SAVE(ptr) 1325 1326 DIRAPPEND(_PATH_BIN); 1327 DIRAPPEND(_PATH_USRBIN); 1328 1329 #undef DIRAPPEND 1330 1331 #if 0 1332 if (euid != 0 && uid != 0) 1333 *blkp++ = Strsave(STRdot); 1334 #endif 1335 1336 *blkp = NULL; 1337 return (blk); 1338 } 1339 #endif /* _PATH_DEFPATH */ 1340 1341 void 1342 printprompt(void) 1343 { 1344 Char *cp; 1345 1346 if (!whyles) { 1347 for (cp = value(STRprompt); *cp; cp++) 1348 if (*cp == HIST) 1349 (void)fprintf(cshout, "%d", eventno + 1); 1350 else { 1351 if (*cp == '\\' && cp[1] == HIST) 1352 cp++; 1353 (void)vis_fputc(*cp | QUOTE, cshout); 1354 } 1355 } 1356 else 1357 /* 1358 * Prompt for forward reading loop body content. 1359 */ 1360 (void)fprintf(cshout, "? "); 1361 (void)fflush(cshout); 1362 } 1363