1/* $NetBSD: csh.c,v 1.43 2012/01/22 18:36:14 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 40static char sccsid[] = "@(#)csh.c 8.2 (Berkeley) 10/12/93"; 41#else 42__RCSID("$NetBSD: csh.c,v 1.43 2012/01/22 18:36:14 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 80Char *dumphist[] = {STRhistory, STRmh, 0, 0}; 81Char *loadhist[] = {STRsource, STRmh, STRtildothist, 0}; 82 83int nofile = 0; 84int batch = 0; 85int enterhist = 0; 86int fast = 0; 87int mflag = 0; 88int nexececho = 0; 89int nverbose = 0; 90int prompt = 1; 91int quitit = 0; 92int reenter = 0; 93 94extern char **environ; 95 96static int readf(void *, char *, int); 97static off_t seekf(void *, off_t, int); 98static int writef(void *, const char *, int); 99static int closef(void *); 100static int srccat(Char *, Char *); 101static int srcfile(const char *, int, int); 102__dead static void phup(int); 103static void srcunit(int, int, int); 104static void mailchk(void); 105#ifndef _PATH_DEFPATH 106static Char **defaultpath(void); 107#endif 108 109int main(int, char *[]); 110 111int 112main(int argc, char *argv[]) 113{ 114 struct sigaction oact; 115 Char *cp; 116 char *tcp, **tempv; 117 const char *ecp; 118 sigset_t nsigset; 119 int f; 120 121 cshin = stdin; 122 cshout = stdout; 123 csherr = stderr; 124 125 setprogname(argv[0]); 126 settimes(); /* Immed. estab. timing base */ 127 128 /* 129 * Initialize non constant strings 130 */ 131#ifdef _PATH_BSHELL 132 STR_BSHELL = SAVE(_PATH_BSHELL); 133#endif 134#ifdef _PATH_CSHELL 135 STR_SHELLPATH = SAVE(_PATH_CSHELL); 136#endif 137 STR_environ = blk2short(environ); 138 environ = short2blk(STR_environ); /* So that we can free it */ 139 STR_WORD_CHARS = SAVE(WORD_CHARS); 140 141 HIST = '!'; 142 HISTSUB = '^'; 143 word_chars = STR_WORD_CHARS; 144 145 tempv = argv; 146 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 147 quitit = 1; 148 uid = getuid(); 149 gid = getgid(); 150 euid = geteuid(); 151 egid = getegid(); 152 /* 153 * We are a login shell if: 1. we were invoked as -<something> and we had 154 * no arguments 2. or we were invoked only with the -l flag 155 */ 156 loginsh = (**tempv == '-' && argc == 1) || 157 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 158 tempv[1][2] == '\0'); 159 160 if (loginsh && **tempv != '-') { 161 /* 162 * Mangle the argv space 163 */ 164 tempv[1][0] = '\0'; 165 tempv[1][1] = '\0'; 166 tempv[1] = NULL; 167 for (tcp = *tempv; *tcp++;) 168 continue; 169 for (tcp--; tcp >= *tempv; tcp--) 170 tcp[1] = tcp[0]; 171 *++tcp = '-'; 172 argc--; 173 } 174 if (loginsh) 175 (void)time(&chktim); 176 177 AsciiOnly = 1; 178#ifdef NLS 179 (void)setlocale(LC_ALL, ""); 180 { 181 int k; 182 183 for (k = 0200; k <= 0377 && !Isprint(k); k++) 184 continue; 185 AsciiOnly = k > 0377; 186 } 187#else 188 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 189#endif /* NLS */ 190 191 /* 192 * Move the descriptors to safe places. The variable didfds is 0 while we 193 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 194 * prefer to use these. 195 */ 196 initdesc(); 197 /* 198 * XXX: This is to keep programs that use stdio happy. 199 * what we really want is freunopen() .... 200 * Closing cshin cshout and csherr (which are really stdin stdout 201 * and stderr at this point and then reopening them in the same order 202 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 203 * If that was not the case builtins like printf that use stdio 204 * would break. But in any case we could fix that with memcpy and 205 * a bit of pointer manipulation... 206 * Fortunately this is not needed under the current implementation 207 * of stdio. 208 */ 209 (void)fclose(cshin); 210 (void)fclose(cshout); 211 (void)fclose(csherr); 212 if (!(cshin = funopen((void *) &SHIN, readf, writef, seekf, closef))) 213 exit(1); 214 if (!(cshout = funopen((void *) &SHOUT, readf, writef, seekf, closef))) 215 exit(1); 216 if (!(csherr = funopen((void *) &SHERR, readf, writef, seekf, closef))) 217 exit(1); 218 (void)setvbuf(cshin, NULL, _IOLBF, 0); 219 (void)setvbuf(cshout, NULL, _IOLBF, 0); 220 (void)setvbuf(csherr, NULL, _IOLBF, 0); 221 222 /* 223 * Initialize the shell variables. ARGV and PROMPT are initialized later. 224 * STATUS is also munged in several places. CHILD is munged when 225 * forking/waiting 226 */ 227 set(STRstatus, Strsave(STR0)); 228 229 if ((ecp = getenv("HOME")) != NULL) 230 cp = quote(SAVE(ecp)); 231 else 232 cp = NULL; 233 234 if (cp == NULL) 235 fast = 1; /* No home -> can't read scripts */ 236 else 237 set(STRhome, cp); 238 dinit(cp); /* dinit thinks that HOME == cwd in a login 239 * shell */ 240 /* 241 * Grab other useful things from the environment. Should we grab 242 * everything?? 243 */ 244 if ((ecp = getenv("LOGNAME")) != NULL || 245 (ecp = getenv("USER")) != NULL) 246 set(STRuser, quote(SAVE(ecp))); 247 if ((ecp = getenv("TERM")) != NULL) 248 set(STRterm, quote(SAVE(ecp))); 249 250 /* 251 * Re-initialize path if set in environment 252 */ 253 if ((ecp = getenv("PATH")) == NULL) { 254#ifdef _PATH_DEFPATH 255 importpath(str2short(_PATH_DEFPATH)); 256#else 257 setq(STRpath, defaultpath(), &shvhed); 258#endif 259 } else { 260 importpath(str2short(ecp)); 261 } 262 263 set(STRshell, Strsave(STR_SHELLPATH)); 264 265 doldol = putn((int) getpid()); /* For $$ */ 266 shtemp = Strspl(STRtmpsh, doldol); /* For << */ 267 268 /* 269 * Record the interrupt states from the parent process. If the parent is 270 * non-interruptible our hand must be forced or we (and our children) won't 271 * be either. Our children inherit termination from our parent. We catch it 272 * only if we are the login shell. 273 */ 274 /* parents interruptibility */ 275 (void)sigaction(SIGINT, NULL, &oact); 276 parintr = oact.sa_handler; 277 (void)sigaction(SIGTERM, NULL, &oact); 278 parterm = oact.sa_handler; 279 280 /* catch these all, login shell or not */ 281 (void)signal(SIGHUP, phup); /* exit processing on HUP */ 282 (void)signal(SIGXCPU, phup); /* ...and on XCPU */ 283 (void)signal(SIGXFSZ, phup); /* ...and on XFSZ */ 284 285 /* 286 * Process the arguments. 287 * 288 * Note that processing of -v/-x is actually delayed till after script 289 * processing. 290 * 291 * We set the first character of our name to be '-' if we are a shell 292 * running interruptible commands. Many programs which examine ps'es 293 * use this to filter such shells out. 294 */ 295 argc--, tempv++; 296 while (argc > 0 && (tcp = tempv[0])[0] == '-' && *++tcp != '\0' && !batch) { 297 do 298 switch (*tcp++) { 299 case 0: /* - Interruptible, no prompt */ 300 prompt = 0; 301 setintr = 1; 302 nofile = 1; 303 break; 304 case 'b': /* -b Next arg is input file */ 305 batch = 1; 306 break; 307 case 'c': /* -c Command input from arg */ 308 if (argc == 1) 309 xexit(0); 310 argc--, tempv++; 311 arginp = SAVE(tempv[0]); 312 prompt = 0; 313 nofile = 1; 314 break; 315 case 'e': /* -e Exit on any error */ 316 exiterr = 1; 317 break; 318 case 'f': /* -f Fast start */ 319 fast = 1; 320 break; 321 case 'i': /* -i Interactive, even if !intty */ 322 intact = 1; 323 nofile = 1; 324 break; 325 case 'm': /* -m read .cshrc (from su) */ 326 mflag = 1; 327 break; 328 case 'n': /* -n Don't execute */ 329 noexec = 1; 330 break; 331 case 'q': /* -q (Undoc'd) ... die on quit */ 332 quitit = 1; 333 break; 334 case 's': /* -s Read from std input */ 335 nofile = 1; 336 break; 337 case 't': /* -t Read one line from input */ 338 onelflg = 2; 339 prompt = 0; 340 nofile = 1; 341 break; 342 case 'v': /* -v Echo hist expanded input */ 343 nverbose = 1; /* ... later */ 344 break; 345 case 'x': /* -x Echo just before execution */ 346 nexececho = 1; /* ... later */ 347 break; 348 case 'V': /* -V Echo hist expanded input */ 349 setNS(STRverbose); /* NOW! */ 350 break; 351 case 'X': /* -X Echo just before execution */ 352 setNS(STRecho); /* NOW! */ 353 break; 354 355 } while (*tcp); 356 tempv++, argc--; 357 } 358 359 if (quitit) /* With all due haste, for debugging */ 360 (void)signal(SIGQUIT, SIG_DFL); 361 362 /* 363 * Unless prevented by -, -c, -i, -s, or -t, if there are remaining 364 * arguments the first of them is the name of a shell file from which to 365 * read commands. 366 */ 367 if (nofile == 0 && argc > 0) { 368 nofile = open(tempv[0], O_RDONLY); 369 if (nofile < 0) { 370 child = 1; /* So this doesn't return */ 371 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 372 } 373 ffile = SAVE(tempv[0]); 374 /* 375 * Replace FSHIN. Handle /dev/std{in,out,err} specially 376 * since once they are closed we cannot open them again. 377 * In that case we use our own saved descriptors 378 */ 379 if ((SHIN = dmove(nofile, FSHIN)) < 0) 380 switch(nofile) { 381 case 0: 382 SHIN = FSHIN; 383 break; 384 case 1: 385 SHIN = FSHOUT; 386 break; 387 case 2: 388 SHIN = FSHERR; 389 break; 390 default: 391 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 392 /* NOTREACHED */ 393 } 394 (void)ioctl(SHIN, FIOCLEX, NULL); 395 prompt = 0; 396 /* argc not used any more */ tempv++; 397 } 398 399 intty = isatty(SHIN); 400 intty |= intact; 401 if (intty || (intact && isatty(SHOUT))) { 402 if (!batch && (uid != euid || gid != egid)) { 403 errno = EACCES; 404 child = 1; /* So this doesn't return */ 405 stderror(ERR_SYSTEM, "csh", strerror(errno)); 406 } 407 } 408 /* 409 * Decide whether we should play with signals or not. If we are explicitly 410 * told (via -i, or -) or we are a login shell (arg0 starts with -) or the 411 * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx") 412 * Note that in only the login shell is it likely that parent may have set 413 * signals to be ignored 414 */ 415 if (loginsh || intact || (intty && isatty(SHOUT))) 416 setintr = 1; 417 settell(); 418 /* 419 * Save the remaining arguments in argv. 420 */ 421 setq(STRargv, blk2short(tempv), &shvhed); 422 423 /* 424 * Set up the prompt. 425 */ 426 if (prompt) { 427 set(STRprompt, Strsave(uid == 0 ? STRsymhash : STRsymcent)); 428 /* that's a meta-questionmark */ 429 set(STRprompt2, Strsave(STRmquestion)); 430 } 431 432 /* 433 * If we are an interactive shell, then start fiddling with the signals; 434 * this is a tricky game. 435 */ 436 shpgrp = getpgrp(); 437 opgrp = tpgrp = -1; 438 if (setintr) { 439 **argv = '-'; 440 if (!quitit) /* Wary! */ 441 (void)signal(SIGQUIT, SIG_IGN); 442 (void)signal(SIGINT, pintr); 443 sigemptyset(&nsigset); 444 (void)sigaddset(&nsigset, SIGINT); 445 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 446 (void)signal(SIGTERM, SIG_IGN); 447 if (quitit == 0 && arginp == 0) { 448 (void)signal(SIGTSTP, SIG_IGN); 449 (void)signal(SIGTTIN, SIG_IGN); 450 (void)signal(SIGTTOU, SIG_IGN); 451 /* 452 * Wait till in foreground, in case someone stupidly runs csh & 453 * dont want to try to grab away the tty. 454 */ 455 if (isatty(FSHERR)) 456 f = FSHERR; 457 else if (isatty(FSHOUT)) 458 f = FSHOUT; 459 else if (isatty(OLDSTD)) 460 f = OLDSTD; 461 else 462 f = -1; 463 retry: 464 if ((tpgrp = tcgetpgrp(f)) != -1) { 465 if (tpgrp != shpgrp) { 466 sig_t old = signal(SIGTTIN, SIG_DFL); 467 (void)kill(0, SIGTTIN); 468 (void)signal(SIGTTIN, old); 469 goto retry; 470 } 471 opgrp = shpgrp; 472 shpgrp = getpid(); 473 tpgrp = shpgrp; 474 /* 475 * Setpgid will fail if we are a session leader and 476 * mypid == mypgrp (POSIX 4.3.3) 477 */ 478 if (opgrp != shpgrp) 479 if (setpgid(0, shpgrp) == -1) 480 goto notty; 481 /* 482 * We do that after we set our process group, to make sure 483 * that the process group belongs to a process in the same 484 * session as the tty (our process and our group) (POSIX 7.2.4) 485 */ 486 if (tcsetpgrp(f, shpgrp) == -1) 487 goto notty; 488 (void)ioctl(dcopy(f, FSHTTY), FIOCLEX, NULL); 489 } 490 if (tpgrp == -1) { 491notty: 492 (void)fprintf(csherr, "Warning: no access to tty (%s).\n", 493 strerror(errno)); 494 (void)fprintf(csherr, "Thus no job control in this shell.\n"); 495 } 496 } 497 } 498 if ((setintr == 0) && (parintr == SIG_DFL)) 499 setintr = 1; 500 (void)signal(SIGCHLD, pchild); /* while signals not ready */ 501 502 /* 503 * Set an exit here in case of an interrupt or error reading the shell 504 * start-up scripts. 505 */ 506 reenter = setexit(); /* PWP */ 507 haderr = 0; /* In case second time through */ 508 if (!fast && reenter == 0) { 509 /* Will have value(STRhome) here because set fast if don't */ 510 { 511 sig_t oparintr; 512 sigset_t osigset; 513 int osetintr; 514 515 oparintr = parintr; 516 osetintr = setintr; 517 sigemptyset(&nsigset); 518 (void)sigaddset(&nsigset, SIGINT); 519 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 520 521 setintr = 0; 522 parintr = SIG_IGN; /* Disable onintr */ 523#ifdef _PATH_DOTCSHRC 524 (void)srcfile(_PATH_DOTCSHRC, 0, 0); 525#endif 526 if (!fast && !arginp && !onelflg) 527 dohash(NULL, NULL); 528#ifdef _PATH_DOTLOGIN 529 if (loginsh) 530 (void)srcfile(_PATH_DOTLOGIN, 0, 0); 531#endif 532 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 533 setintr = osetintr; 534 parintr = oparintr; 535 } 536 (void)srccat(value(STRhome), STRsldotcshrc); 537 538 if (!fast && !arginp && !onelflg && !havhash) 539 dohash(NULL, NULL); 540 /* 541 * Source history before .login so that it is available in .login 542 */ 543 if ((cp = value(STRhistfile)) != STRNULL) 544 loadhist[2] = cp; 545 dosource(loadhist, NULL); 546 if (loginsh) 547 (void)srccat(value(STRhome), STRsldotlogin); 548 } 549 550 /* 551 * Now are ready for the -v and -x flags 552 */ 553 if (nverbose) 554 setNS(STRverbose); 555 if (nexececho) 556 setNS(STRecho); 557 558 /* 559 * All the rest of the world is inside this call. The argument to process 560 * indicates whether it should catch "error unwinds". Thus if we are a 561 * interactive shell our call here will never return by being blown past on 562 * an error. 563 */ 564 process(setintr); 565 566 /* 567 * Mop-up. 568 */ 569 if (intty) { 570 if (loginsh) { 571 (void)fprintf(cshout, "logout\n"); 572 (void)close(SHIN); 573 child = 1; 574 goodbye(); 575 } 576 else { 577 (void)fprintf(cshout, "exit\n"); 578 } 579 } 580 rechist(); 581 exitstat(); 582 /* NOTREACHED */ 583} 584 585void 586untty(void) 587{ 588 if (tpgrp > 0) { 589 (void)setpgid(0, opgrp); 590 (void)tcsetpgrp(FSHTTY, opgrp); 591 } 592} 593 594void 595importpath(Char *cp) 596{ 597 Char *dp, **pv; 598 int c, i; 599 600 i = 0; 601 for (dp = cp; *dp; dp++) 602 if (*dp == ':') 603 i++; 604 /* 605 * i+2 where i is the number of colons in the path. There are i+1 606 * directories in the path plus we need room for a zero terminator. 607 */ 608 pv = (Char **)xcalloc((size_t) (i + 2), sizeof(Char **)); 609 dp = cp; 610 i = 0; 611 if (*dp) 612 for (;;) { 613 if ((c = *dp) == ':' || c == 0) { 614 *dp = 0; 615 pv[i++] = Strsave(*cp ? cp : STRdot); 616 if (c) { 617 cp = dp + 1; 618 *dp = ':'; 619 } 620 else 621 break; 622 } 623 dp++; 624 } 625 pv[i] = 0; 626 setq(STRpath, pv, &shvhed); 627} 628 629/* 630 * Source to the file which is the catenation of the argument names. 631 */ 632static int 633srccat(Char *cp, Char *dp) 634{ 635 Char *ep; 636 char *ptr; 637 638 ep = Strspl(cp, dp); 639 ptr = short2str(ep); 640 xfree((ptr_t) ep); 641 return srcfile(ptr, mflag ? 0 : 1, 0); 642} 643 644/* 645 * Source to a file putting the file descriptor in a safe place (> 2). 646 */ 647static int 648srcfile(const char *f, int onlyown, int flag) 649{ 650 int unit; 651 652 if ((unit = open(f, O_RDONLY)) == -1) 653 return 0; 654 unit = dmove(unit, -1); 655 656 (void) ioctl(unit, FIOCLEX, NULL); 657 srcunit(unit, onlyown, flag); 658 return 1; 659} 660 661/* 662 * Source to a unit. If onlyown it must be our file or our group or 663 * we don't chance it. This occurs on ".cshrc"s and the like. 664 */ 665int insource; 666 667static void 668srcunit(int unit, int onlyown, int hflg) 669{ 670 /* We have to push down a lot of state here */ 671 /* All this could go into a structure */ 672 struct whyle *oldwhyl; 673 struct Bin saveB; 674 sigset_t nsigset, osigset; 675 jmp_buf oldexit; 676 Char *oarginp, *oevalp, **oevalvec, *ogointr; 677 char OHIST; 678 int oSHIN, oinsource, oldintty, oonelflg; 679 int oenterhist, otell; 680 /* The (few) real local variables */ 681 int my_reenter; 682 683 oSHIN = -1; 684 oldintty = intty; 685 oinsource = insource; 686 oldwhyl = whyles; 687 ogointr = gointr; 688 oarginp = arginp; 689 oevalp = evalp; 690 oevalvec = evalvec; 691 oonelflg = onelflg; 692 oenterhist = enterhist; 693 OHIST = HIST; 694 otell = cantell; 695 696 if (unit < 0) 697 return; 698 if (didfds) 699 donefds(); 700 if (onlyown) { 701 struct stat stb; 702 703 if (fstat(unit, &stb) < 0) { 704 (void)close(unit); 705 return; 706 } 707 } 708 709 /* 710 * There is a critical section here while we are pushing down the input 711 * stream since we have stuff in different structures. If we weren't 712 * careful an interrupt could corrupt SHIN's Bin structure and kill the 713 * shell. 714 * 715 * We could avoid the critical region by grouping all the stuff in a single 716 * structure and pointing at it to move it all at once. This is less 717 * efficient globally on many variable references however. 718 */ 719 insource = 1; 720 getexit(oldexit); 721 722 if (setintr) { 723 sigemptyset(&nsigset); 724 (void)sigaddset(&nsigset, SIGINT); 725 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 726 } 727 /* Setup the new values of the state stuff saved above */ 728 (void)memcpy(&saveB, &B, sizeof(B)); 729 fbuf = NULL; 730 fseekp = feobp = fblocks = 0; 731 oSHIN = SHIN, SHIN = unit, arginp = 0, onelflg = 0; 732 intty = isatty(SHIN), whyles = 0, gointr = 0; 733 evalvec = 0; 734 evalp = 0; 735 enterhist = hflg; 736 if (enterhist) 737 HIST = '\0'; 738 739 /* 740 * Now if we are allowing commands to be interrupted, we let ourselves be 741 * interrupted. 742 */ 743 if (setintr) 744 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 745 settell(); 746 747 if ((my_reenter = setexit()) == 0) 748 process(0); /* 0 -> blow away on errors */ 749 750 if (setintr) 751 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 752 if (oSHIN >= 0) { 753 int i; 754 755 /* We made it to the new state... free up its storage */ 756 /* This code could get run twice but xfree doesn't care */ 757 for (i = 0; i < fblocks; i++) 758 xfree((ptr_t) fbuf[i]); 759 xfree((ptr_t) fbuf); 760 761 /* Reset input arena */ 762 (void)memcpy(&B, &saveB, sizeof(B)); 763 764 (void)close(SHIN), SHIN = oSHIN; 765 arginp = oarginp, onelflg = oonelflg; 766 evalp = oevalp, evalvec = oevalvec; 767 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 768 if (enterhist) 769 HIST = OHIST; 770 enterhist = oenterhist; 771 cantell = otell; 772 } 773 774 resexit(oldexit); 775 /* 776 * If process reset() (effectively an unwind) then we must also unwind. 777 */ 778 if (my_reenter) 779 stderror(ERR_SILENT); 780 insource = oinsource; 781} 782 783void 784rechist(void) 785{ 786 Char buf[BUFSIZE], hbuf[BUFSIZE], *hfile; 787 int fp, ftmp, oldidfds; 788 struct varent *shist; 789 790 if (!fast) { 791 /* 792 * If $savehist is just set, we use the value of $history 793 * else we use the value in $savehist 794 */ 795 if ((shist = adrof(STRsavehist)) != NULL) { 796 if (shist->vec[0][0] != '\0') 797 (void)Strcpy(hbuf, shist->vec[0]); 798 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 799 (void)Strcpy(hbuf, shist->vec[0]); 800 else 801 return; 802 } 803 else 804 return; 805 806 if ((hfile = value(STRhistfile)) == STRNULL) { 807 hfile = Strcpy(buf, value(STRhome)); 808 (void) Strcat(buf, STRsldthist); 809 } 810 811 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 812 0600)) == -1) 813 return; 814 815 oldidfds = didfds; 816 didfds = 0; 817 ftmp = SHOUT; 818 SHOUT = fp; 819 dumphist[2] = hbuf; 820 dohist(dumphist, NULL); 821 SHOUT = ftmp; 822 (void)close(fp); 823 didfds = oldidfds; 824 } 825} 826 827void 828goodbye(void) 829{ 830 rechist(); 831 832 if (loginsh) { 833 (void)signal(SIGQUIT, SIG_IGN); 834 (void)signal(SIGINT, SIG_IGN); 835 (void)signal(SIGTERM, SIG_IGN); 836 setintr = 0; /* No interrupts after "logout" */ 837 if (!(adrof(STRlogout))) 838 set(STRlogout, STRnormal); 839#ifdef _PATH_DOTLOGOUT 840 (void)srcfile(_PATH_DOTLOGOUT, 0, 0); 841#endif 842 if (adrof(STRhome)) 843 (void)srccat(value(STRhome), STRsldtlogout); 844 } 845 exitstat(); 846 /* NOTREACHED */ 847} 848 849__dead void 850exitstat(void) 851{ 852 Char *s; 853#ifdef PROF 854 monitor(0); 855#endif 856 /* 857 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 858 * directly because we poke child here. Otherwise we might continue 859 * unwarrantedly (sic). 860 */ 861 child = 1; 862 s = value(STRstatus); 863 xexit(s ? getn(s) : 0); 864 /* NOTREACHED */ 865} 866 867/* 868 * in the event of a HUP we want to save the history 869 */ 870static void 871phup(int sig) 872{ 873 rechist(); 874 875 /* 876 * We kill the last foreground process group. It then becomes 877 * responsible to propagate the SIGHUP to its progeny. 878 */ 879 { 880 struct process *pp, *np; 881 882 for (pp = proclist.p_next; pp; pp = pp->p_next) { 883 np = pp; 884 /* 885 * Find if this job is in the foreground. It could be that 886 * the process leader has exited and the foreground flag 887 * is cleared for it. 888 */ 889 do 890 /* 891 * If a process is in the foreground; we try to kill 892 * its process group. If we succeed, then the 893 * whole job is gone. Otherwise we keep going... 894 * But avoid sending HUP to the shell again. 895 */ 896 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 897 kill(-np->p_jobid, SIGHUP) != -1) { 898 /* In case the job was suspended... */ 899 (void)kill(-np->p_jobid, SIGCONT); 900 break; 901 } 902 while ((np = np->p_friends) != pp); 903 } 904 } 905 xexit(sig); 906 /* NOTREACHED */ 907} 908 909Char *jobargv[2] = {STRjobs, 0}; 910 911/* 912 * Catch an interrupt, e.g. during lexical input. 913 * If we are an interactive shell, we reset the interrupt catch 914 * immediately. In any case we drain the shell output, 915 * and finally go through the normal error mechanism, which 916 * gets a chance to make the shell go away. 917 */ 918/* ARGSUSED */ 919void 920pintr(int notused) 921{ 922 pintr1(1); 923 /* NOTREACHED */ 924} 925 926void 927pintr1(int wantnl) 928{ 929 Char **v; 930 sigset_t nsigset, osigset; 931 932 sigemptyset(&nsigset); 933 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 934 if (setintr) { 935 nsigset = osigset; 936 (void)sigdelset(&nsigset, SIGINT); 937 (void)sigprocmask(SIG_SETMASK, &nsigset, NULL); 938 if (pjobs) { 939 pjobs = 0; 940 (void)fprintf(cshout, "\n"); 941 dojobs(jobargv, NULL); 942 stderror(ERR_NAME | ERR_INTR); 943 } 944 } 945 (void)sigdelset(&osigset, SIGCHLD); 946 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 947 (void)fpurge(cshout); 948 (void)endpwent(); 949 950 /* 951 * If we have an active "onintr" then we search for the label. Note that if 952 * one does "onintr -" then we shan't be interruptible so we needn't worry 953 * about that here. 954 */ 955 if (gointr) { 956 gotolab(gointr); 957 timflg = 0; 958 if ((v = pargv) != NULL) 959 pargv = 0, blkfree(v); 960 if ((v = gargv) != NULL) 961 gargv = 0, blkfree(v); 962 reset(); 963 } 964 else if (intty && wantnl) { 965 (void)fputc('\r', cshout); 966 (void)fputc('\n', cshout); 967 } 968 stderror(ERR_SILENT); 969 /* NOTREACHED */ 970} 971 972/* 973 * Process is the main driving routine for the shell. 974 * It runs all command processing, except for those within { ... } 975 * in expressions (which is run by a routine evalav in sh.exp.c which 976 * is a stripped down process), and `...` evaluation which is run 977 * also by a subset of this code in sh.glob.c in the routine backeval. 978 * 979 * The code here is a little strange because part of it is interruptible 980 * and hence freeing of structures appears to occur when none is necessary 981 * if this is ignored. 982 * 983 * Note that if catch is not set then we will unwind on any error. 984 * If an end-of-file occurs, we return. 985 */ 986static struct command *savet = NULL; 987 988void 989process(int catch) 990{ 991 struct command *t; 992 jmp_buf osetexit; 993 sigset_t nsigset; 994 995 t = savet; 996 savet = NULL; 997 getexit(osetexit); 998 for (;;) { 999 pendjob(); 1000 paraml.next = paraml.prev = ¶ml; 1001 paraml.word = STRNULL; 1002 (void)setexit(); 1003 justpr = enterhist; /* execute if not entering history */ 1004 1005 /* 1006 * Interruptible during interactive reads 1007 */ 1008 if (setintr) { 1009 sigemptyset(&nsigset); 1010 (void)sigaddset(&nsigset, SIGINT); 1011 (void)sigprocmask(SIG_UNBLOCK, &nsigset, NULL); 1012 } 1013 1014 /* 1015 * For the sake of reset() 1016 */ 1017 freelex(¶ml); 1018 if (savet) 1019 freesyn(savet), savet = NULL; 1020 1021 if (haderr) { 1022 if (!catch) { 1023 /* unwind */ 1024 doneinp = 0; 1025 resexit(osetexit); 1026 savet = t; 1027 reset(); 1028 } 1029 haderr = 0; 1030 /* 1031 * Every error is eventually caught here or the shell dies. It is 1032 * at this point that we clean up any left-over open files, by 1033 * closing all but a fixed number of pre-defined files. Thus 1034 * routines don't have to worry about leaving files open due to 1035 * deeper errors... they will get closed here. 1036 */ 1037 closem(); 1038 continue; 1039 } 1040 if (doneinp) { 1041 doneinp = 0; 1042 break; 1043 } 1044 if (chkstop) 1045 chkstop--; 1046 if (neednote) 1047 pnote(); 1048 if (intty && prompt && evalvec == 0) { 1049 mailchk(); 1050 /* 1051 * If we are at the end of the input buffer then we are going to 1052 * read fresh stuff. Otherwise, we are rereading input and don't 1053 * need or want to prompt. 1054 */ 1055 if (aret == F_SEEK && fseekp == feobp) 1056 printprompt(); 1057 (void)fflush(cshout); 1058 } 1059 if (seterr) { 1060 xfree((ptr_t) seterr); 1061 seterr = NULL; 1062 } 1063 1064 /* 1065 * Echo not only on VERBOSE, but also with history expansion. If there 1066 * is a lexical error then we forego history echo. 1067 */ 1068 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1069 int odidfds = didfds; 1070 fflush(csherr); 1071 didfds = 0; 1072 prlex(csherr, ¶ml); 1073 fflush(csherr); 1074 didfds = odidfds; 1075 } 1076 1077 /* 1078 * The parser may lose space if interrupted. 1079 */ 1080 if (setintr) 1081 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 1082 1083 /* 1084 * Save input text on the history list if reading in old history, or it 1085 * is from the terminal at the top level and not in a loop. 1086 * 1087 * PWP: entry of items in the history list while in a while loop is done 1088 * elsewhere... 1089 */ 1090 if (enterhist || (catch && intty && !whyles)) 1091 savehist(¶ml); 1092 1093 /* 1094 * Print lexical error messages, except when sourcing history lists. 1095 */ 1096 if (!enterhist && seterr) 1097 stderror(ERR_OLD); 1098 1099 /* 1100 * If had a history command :p modifier then this is as far as we 1101 * should go 1102 */ 1103 if (justpr) 1104 reset(); 1105 1106 alias(¶ml); 1107 1108 /* 1109 * Parse the words of the input into a parse tree. 1110 */ 1111 savet = syntax(paraml.next, ¶ml, 0); 1112 if (seterr) 1113 stderror(ERR_OLD); 1114 1115 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1116 1117 /* 1118 * Made it! 1119 */ 1120 freelex(¶ml); 1121 freesyn((struct command *) savet), savet = NULL; 1122 } 1123 resexit(osetexit); 1124 savet = t; 1125} 1126 1127void 1128/*ARGSUSED*/ 1129dosource(Char **v, struct command *t) 1130{ 1131 Char buf[BUFSIZE], *f; 1132 int hflg; 1133 1134 hflg = 0; 1135 v++; 1136 if (*v && eq(*v, STRmh)) { 1137 if (*++v == NULL) 1138 stderror(ERR_NAME | ERR_HFLAG); 1139 hflg++; 1140 } 1141 (void)Strcpy(buf, *v); 1142 f = globone(buf, G_ERROR); 1143 (void)strcpy((char *)buf, short2str(f)); 1144 xfree((ptr_t) f); 1145 if (!srcfile((char *)buf, 0, hflg) && !hflg) 1146 stderror(ERR_SYSTEM, (char *)buf, strerror(errno)); 1147} 1148 1149/* 1150 * Check for mail. 1151 * If we are a login shell, then we don't want to tell 1152 * about any mail file unless its been modified 1153 * after the time we started. 1154 * This prevents us from telling the user things he already 1155 * knows, since the login program insists on saying 1156 * "You have mail." 1157 */ 1158static void 1159mailchk(void) 1160{ 1161 struct stat stb; 1162 struct varent *v; 1163 Char **vp; 1164 time_t t; 1165 int cnt, intvl; 1166 int new; 1167 1168 v = adrof(STRmail); 1169 if (v == 0) 1170 return; 1171 (void)time(&t); 1172 vp = v->vec; 1173 cnt = blklen(vp); 1174 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1175 if (intvl < 1) 1176 intvl = 1; 1177 if (chktim + intvl > t) 1178 return; 1179 for (; *vp; vp++) { 1180 if (stat(short2str(*vp), &stb) < 0) 1181 continue; 1182 new = stb.st_mtime > time0.tv_sec; 1183 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1184 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1185 (loginsh && !new)) 1186 continue; 1187 if (cnt == 1) 1188 (void)fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1189 else 1190 (void)fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1191 vis_str(*vp)); 1192 } 1193 chktim = t; 1194} 1195 1196/* 1197 * Extract a home directory from the password file 1198 * The argument points to a buffer where the name of the 1199 * user whose home directory is sought is currently. 1200 * We write the home directory of the user back there. 1201 */ 1202int 1203gethdir(Char *home) 1204{ 1205 struct passwd *pw; 1206 Char *h; 1207 1208 /* 1209 * Is it us? 1210 */ 1211 if (*home == '\0') { 1212 if ((h = value(STRhome)) != NULL) { 1213 (void)Strcpy(home, h); 1214 return 0; 1215 } 1216 else 1217 return 1; 1218 } 1219 1220 if ((pw = getpwnam(short2str(home))) != NULL) { 1221 (void)Strcpy(home, str2short(pw->pw_dir)); 1222 return 0; 1223 } 1224 else 1225 return 1; 1226} 1227 1228/* 1229 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1230 * We also check if the shell has already changed the descriptor to point to 1231 * 0, 1, 2 when didfds is set. 1232 */ 1233#define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1234 1235static int 1236readf(void *oreo, char *buf, int siz) 1237{ 1238 return read(DESC(oreo), buf, siz); 1239} 1240 1241 1242static int 1243writef(void *oreo, const char *buf, int siz) 1244{ 1245 return write(DESC(oreo), buf, siz); 1246} 1247 1248static off_t 1249seekf(void *oreo, off_t off, int whence) 1250{ 1251 return lseek(DESC(oreo), off, whence); 1252} 1253 1254 1255static int 1256closef(void *oreo) 1257{ 1258 return close(DESC(oreo)); 1259} 1260 1261 1262/* 1263 * Print the visible version of a string. 1264 */ 1265int 1266vis_fputc(int ch, FILE *fp) 1267{ 1268 char uenc[5]; /* 4 + NULL */ 1269 1270 if (ch & QUOTE) 1271 return fputc(ch & TRIM, fp); 1272 /* 1273 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1274 * be encoded, but currently there is no way in vis to do that. 1275 */ 1276 (void)vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1277 return (fputs(uenc, fp)); 1278} 1279 1280/* 1281 * Move the initial descriptors to their eventual 1282 * resting places, closing all other units. 1283 */ 1284void 1285initdesc(void) 1286{ 1287 didfds = 0; /* 0, 1, 2 aren't set up */ 1288 (void)ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1289 (void)ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1290 (void)ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1291 (void)ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1292 closem(); 1293} 1294 1295 1296__dead void 1297#ifdef PROF 1298done(int i) 1299#else 1300xexit(int i) 1301#endif 1302{ 1303 untty(); 1304 _exit(i); 1305 /* NOTREACHED */ 1306} 1307 1308#ifndef _PATH_DEFPATH 1309static Char ** 1310defaultpath(void) 1311{ 1312 struct stat stb; 1313 Char **blk, **blkp; 1314 char *ptr; 1315 1316 blkp = blk = (Char **)xmalloc((size_t) sizeof(Char *) * 10); 1317 1318#define DIRAPPEND(a) \ 1319 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1320 *blkp++ = SAVE(ptr) 1321#ifdef RESCUEDIR 1322 DIRAPPEND(RESCUEDIR); 1323#endif 1324 DIRAPPEND(_PATH_BIN); 1325 DIRAPPEND(_PATH_USRBIN); 1326 1327#undef DIRAPPEND 1328 1329#if 0 1330 if (euid != 0 && uid != 0) 1331 *blkp++ = Strsave(STRdot); 1332#endif 1333 1334 *blkp = NULL; 1335 return (blk); 1336} 1337#endif /* _PATH_DEFPATH */ 1338 1339void 1340printprompt(void) 1341{ 1342 Char *cp; 1343 1344 if (!whyles) { 1345 for (cp = value(STRprompt); *cp; cp++) 1346 if (*cp == HIST) 1347 (void)fprintf(cshout, "%d", eventno + 1); 1348 else { 1349 if (*cp == '\\' && cp[1] == HIST) 1350 cp++; 1351 (void)vis_fputc(*cp | QUOTE, cshout); 1352 } 1353 } 1354 else 1355 /* 1356 * Prompt for forward reading loop body content. 1357 */ 1358 (void)fprintf(cshout, "? "); 1359 (void)fflush(cshout); 1360} 1361