1 /* $NetBSD: csh.c,v 1.49 2020/01/12 18:36:55 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1980, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1980, 1991, 1993\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)csh.c 8.2 (Berkeley) 10/12/93"; 41 #else 42 __RCSID("$NetBSD: csh.c,v 1.49 2020/01/12 18:36:55 christos Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #include <sys/types.h> 47 #include <sys/ioctl.h> 48 #include <sys/stat.h> 49 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <locale.h> 53 #include <paths.h> /* should this be included in pathnames.h instead? */ 54 #include <pwd.h> 55 #include <stdarg.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <time.h> 59 #include <unistd.h> 60 #include <vis.h> 61 62 #include "csh.h" 63 #include "extern.h" 64 #include "pathnames.h" 65 #include "proc.h" 66 67 /* 68 * C Shell 69 * 70 * Bill Joy, UC Berkeley, California, USA 71 * October 1978, May 1980 72 * 73 * Jim Kulp, IIASA, Laxenburg, Austria 74 * April 1980 75 * 76 * Christos Zoulas, Cornell University 77 * June, 1991 78 */ 79 80 Char *dumphist[] = {STRhistory, STRmh, 0, 0}; 81 Char *tildehist[] = {STRsource, STRmh, STRtildothist, 0}; 82 83 int nofile = 0; 84 int batch = 0; 85 int enterhist = 0; 86 int fast = 0; 87 int mflag = 0; 88 int nexececho = 0; 89 int nverbose = 0; 90 int prompt = 1; 91 int quitit = 0; 92 int reenter = 0; 93 94 extern char **environ; 95 96 static ssize_t readf(void *, void *, size_t); 97 static off_t seekf(void *, off_t, int); 98 static ssize_t writef(void *, const void *, size_t); 99 static int closef(void *); 100 static int srccat(Char *, Char *); 101 static int srcfile(const char *, int, int); 102 __dead static void phup(int); 103 static void srcunit(int, int, int); 104 static void mailchk(void); 105 #ifndef _PATH_DEFPATH 106 static Char **defaultpath(void); 107 #endif 108 109 int 110 main(int argc, char *argv[]) 111 { 112 struct sigaction oact; 113 Char *cp; 114 char *tcp, **tempv; 115 const char *ecp; 116 sigset_t nsigset; 117 int f; 118 119 cshin = stdin; 120 cshout = stdout; 121 csherr = stderr; 122 123 setprogname(argv[0]); 124 settimes(); /* Immed. estab. timing base */ 125 126 /* 127 * Initialize non constant strings 128 */ 129 #ifdef _PATH_BSHELL 130 STR_BSHELL = SAVE(_PATH_BSHELL); 131 #endif 132 #ifdef _PATH_CSHELL 133 STR_SHELLPATH = SAVE(_PATH_CSHELL); 134 #endif 135 STR_environ = blk2short(environ); 136 environ = short2blk(STR_environ); /* So that we can free it */ 137 STR_WORD_CHARS = SAVE(WORD_CHARS); 138 139 HIST = '!'; 140 HISTSUB = '^'; 141 word_chars = STR_WORD_CHARS; 142 143 tempv = argv; 144 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 145 quitit = 1; 146 uid = getuid(); 147 gid = getgid(); 148 euid = geteuid(); 149 egid = getegid(); 150 /* 151 * We are a login shell if: 1. we were invoked as -<something> and we had 152 * no arguments 2. or we were invoked only with the -l flag 153 */ 154 loginsh = (**tempv == '-' && argc == 1) || 155 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 156 tempv[1][2] == '\0'); 157 158 if (loginsh && **tempv != '-') { 159 /* 160 * Mangle the argv space 161 */ 162 tempv[1][0] = '\0'; 163 tempv[1][1] = '\0'; 164 tempv[1] = NULL; 165 for (tcp = *tempv; *tcp++;) 166 continue; 167 for (tcp--; tcp >= *tempv; tcp--) 168 tcp[1] = tcp[0]; 169 *++tcp = '-'; 170 argc--; 171 } 172 if (loginsh) 173 (void)time(&chktim); 174 175 AsciiOnly = 1; 176 #ifdef NLS 177 (void)setlocale(LC_ALL, ""); 178 { 179 int k; 180 181 for (k = 0200; k <= 0377 && !Isprint(k); k++) 182 continue; 183 AsciiOnly = k > 0377; 184 } 185 #else 186 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 187 #endif /* NLS */ 188 189 /* 190 * Move the descriptors to safe places. The variable didfds is 0 while we 191 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 192 * prefer to use these. 193 */ 194 initdesc(); 195 /* 196 * XXX: This is to keep programs that use stdio happy. 197 * what we really want is freunopen() .... 198 * Closing cshin cshout and csherr (which are really stdin stdout 199 * and stderr at this point and then reopening them in the same order 200 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 201 * If that was not the case builtins like printf that use stdio 202 * would break. But in any case we could fix that with memcpy and 203 * a bit of pointer manipulation... 204 * Fortunately this is not needed under the current implementation 205 * of stdio. 206 */ 207 (void)fclose(cshin); 208 (void)fclose(cshout); 209 (void)fclose(csherr); 210 if (!(cshin = funopen2((void *) &SHIN, readf, writef, seekf, NULL, 211 closef))) 212 exit(1); 213 if (!(cshout = funopen2((void *) &SHOUT, readf, writef, seekf, NULL, 214 closef))) 215 exit(1); 216 if (!(csherr = funopen2((void *) &SHERR, readf, writef, seekf, NULL, 217 closef))) 218 exit(1); 219 (void)setvbuf(cshin, NULL, _IOLBF, 0); 220 (void)setvbuf(cshout, NULL, _IOLBF, 0); 221 (void)setvbuf(csherr, NULL, _IOLBF, 0); 222 223 /* 224 * Initialize the shell variables. ARGV and PROMPT are initialized later. 225 * STATUS is also munged in several places. CHILD is munged when 226 * forking/waiting 227 */ 228 set(STRstatus, Strsave(STR0)); 229 230 if ((ecp = getenv("HOME")) != NULL) 231 cp = quote(SAVE(ecp)); 232 else 233 cp = NULL; 234 235 if (cp == NULL) 236 fast = 1; /* No home -> can't read scripts */ 237 else 238 set(STRhome, cp); 239 dinit(cp); /* dinit thinks that HOME == cwd in a login 240 * shell */ 241 /* 242 * Grab other useful things from the environment. Should we grab 243 * everything?? 244 */ 245 if ((ecp = getenv("LOGNAME")) != NULL || 246 (ecp = getenv("USER")) != NULL) 247 set(STRuser, quote(SAVE(ecp))); 248 if ((ecp = getenv("TERM")) != NULL) 249 set(STRterm, quote(SAVE(ecp))); 250 251 /* 252 * Re-initialize path if set in environment 253 */ 254 if ((ecp = getenv("PATH")) == NULL) { 255 #ifdef _PATH_DEFPATH 256 importpath(str2short(_PATH_DEFPATH)); 257 #else 258 setq(STRpath, defaultpath(), &shvhed); 259 #endif 260 } else { 261 importpath(str2short(ecp)); 262 } 263 264 set(STRshell, Strsave(STR_SHELLPATH)); 265 266 doldol = putn((int) getpid()); /* For $$ */ 267 shtemp = Strspl(STRtmpsh, doldol); /* For << */ 268 269 /* 270 * Record the interrupt states from the parent process. If the parent is 271 * non-interruptible our hand must be forced or we (and our children) won't 272 * be either. Our children inherit termination from our parent. We catch it 273 * only if we are the login shell. 274 */ 275 /* parents interruptibility */ 276 (void)sigaction(SIGINT, NULL, &oact); 277 parintr = oact.sa_handler; 278 (void)sigaction(SIGTERM, NULL, &oact); 279 parterm = oact.sa_handler; 280 281 /* catch these all, login shell or not */ 282 (void)signal(SIGHUP, phup); /* exit processing on HUP */ 283 (void)signal(SIGXCPU, phup); /* ...and on XCPU */ 284 (void)signal(SIGXFSZ, phup); /* ...and on XFSZ */ 285 286 /* 287 * Process the arguments. 288 * 289 * Note that processing of -v/-x is actually delayed till after script 290 * processing. 291 * 292 * We set the first character of our name to be '-' if we are a shell 293 * running interruptible commands. Many programs which examine ps'es 294 * use this to filter such shells out. 295 */ 296 argc--, tempv++; 297 while (argc > 0 && (tcp = tempv[0])[0] == '-' && *++tcp != '\0' && !batch) { 298 do 299 switch (*tcp++) { 300 case 0: /* - Interruptible, no prompt */ 301 prompt = 0; 302 setintr = 1; 303 nofile = 1; 304 break; 305 case 'b': /* -b Next arg is input file */ 306 batch = 1; 307 break; 308 case 'c': /* -c Command input from arg */ 309 if (argc == 1) 310 xexit(0); 311 argc--, tempv++; 312 arginp = SAVE(tempv[0]); 313 prompt = 0; 314 nofile = 1; 315 break; 316 case 'e': /* -e Exit on any error */ 317 exiterr = 1; 318 break; 319 case 'f': /* -f Fast start */ 320 fast = 1; 321 break; 322 case 'i': /* -i Interactive, even if !intty */ 323 intact = 1; 324 nofile = 1; 325 break; 326 case 'm': /* -m read .cshrc (from su) */ 327 mflag = 1; 328 break; 329 case 'n': /* -n Don't execute */ 330 noexec = 1; 331 break; 332 case 'q': /* -q (Undoc'd) ... die on quit */ 333 quitit = 1; 334 break; 335 case 's': /* -s Read from std input */ 336 nofile = 1; 337 break; 338 case 't': /* -t Read one line from input */ 339 onelflg = 2; 340 prompt = 0; 341 nofile = 1; 342 break; 343 case 'v': /* -v Echo hist expanded input */ 344 nverbose = 1; /* ... later */ 345 break; 346 case 'x': /* -x Echo just before execution */ 347 nexececho = 1; /* ... later */ 348 break; 349 case 'V': /* -V Echo hist expanded input */ 350 setNS(STRverbose); /* NOW! */ 351 break; 352 case 'X': /* -X Echo just before execution */ 353 setNS(STRecho); /* NOW! */ 354 break; 355 356 } while (*tcp); 357 tempv++, argc--; 358 } 359 360 if (quitit) /* With all due haste, for debugging */ 361 (void)signal(SIGQUIT, SIG_DFL); 362 363 /* 364 * Unless prevented by -, -c, -i, -s, or -t, if there are remaining 365 * arguments the first of them is the name of a shell file from which to 366 * read commands. 367 */ 368 if (nofile == 0 && argc > 0) { 369 nofile = open(tempv[0], O_RDONLY); 370 if (nofile < 0) { 371 child = 1; /* So this doesn't return */ 372 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 373 } 374 ffile = SAVE(tempv[0]); 375 /* 376 * Replace FSHIN. Handle /dev/std{in,out,err} specially 377 * since once they are closed we cannot open them again. 378 * In that case we use our own saved descriptors 379 */ 380 if ((SHIN = dmove(nofile, FSHIN)) < 0) 381 switch(nofile) { 382 case 0: 383 SHIN = FSHIN; 384 break; 385 case 1: 386 SHIN = FSHOUT; 387 break; 388 case 2: 389 SHIN = FSHERR; 390 break; 391 default: 392 stderror(ERR_SYSTEM, tempv[0], strerror(errno)); 393 /* NOTREACHED */ 394 } 395 (void)ioctl(SHIN, FIOCLEX, NULL); 396 prompt = 0; 397 /* argc not used any more */ tempv++; 398 } 399 400 intty = isatty(SHIN); 401 intty |= intact; 402 if (intty || (intact && isatty(SHOUT))) { 403 if (!batch && (uid != euid || gid != egid)) { 404 errno = EACCES; 405 child = 1; /* So this doesn't return */ 406 stderror(ERR_SYSTEM, "csh", strerror(errno)); 407 } 408 } 409 /* 410 * Decide whether we should play with signals or not. If we are explicitly 411 * told (via -i, or -) or we are a login shell (arg0 starts with -) or the 412 * input and output are both the ttys("csh", or "csh</dev/ttyx>/dev/ttyx") 413 * Note that in only the login shell is it likely that parent may have set 414 * signals to be ignored 415 */ 416 if (loginsh || intact || (intty && isatty(SHOUT))) 417 setintr = 1; 418 settell(); 419 /* 420 * Save the remaining arguments in argv. 421 */ 422 setq(STRargv, blk2short(tempv), &shvhed); 423 424 /* 425 * Set up the prompt. 426 */ 427 if (prompt) { 428 set(STRprompt, Strsave(uid == 0 ? STRsymhash : STRsymcent)); 429 /* that's a meta-questionmark */ 430 set(STRprompt2, Strsave(STRmquestion)); 431 } 432 433 /* 434 * If we are an interactive shell, then start fiddling with the signals; 435 * this is a tricky game. 436 */ 437 shpgrp = getpgrp(); 438 opgrp = tpgrp = -1; 439 if (setintr) { 440 **argv = '-'; 441 if (!quitit) /* Wary! */ 442 (void)signal(SIGQUIT, SIG_IGN); 443 (void)signal(SIGINT, pintr); 444 sigemptyset(&nsigset); 445 (void)sigaddset(&nsigset, SIGINT); 446 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 447 (void)signal(SIGTERM, SIG_IGN); 448 if (quitit == 0 && arginp == 0) { 449 (void)signal(SIGTSTP, SIG_IGN); 450 (void)signal(SIGTTIN, SIG_IGN); 451 (void)signal(SIGTTOU, SIG_IGN); 452 /* 453 * Wait till in foreground, in case someone stupidly runs csh & 454 * dont want to try to grab away the tty. 455 */ 456 if (isatty(FSHERR)) 457 f = FSHERR; 458 else if (isatty(FSHOUT)) 459 f = FSHOUT; 460 else if (isatty(OLDSTD)) 461 f = OLDSTD; 462 else 463 f = -1; 464 retry: 465 if ((tpgrp = tcgetpgrp(f)) != -1) { 466 if (tpgrp != shpgrp) { 467 sig_t old = signal(SIGTTIN, SIG_DFL); 468 (void)kill(0, SIGTTIN); 469 (void)signal(SIGTTIN, old); 470 goto retry; 471 } 472 opgrp = shpgrp; 473 shpgrp = getpid(); 474 tpgrp = shpgrp; 475 /* 476 * Setpgid will fail if we are a session leader and 477 * mypid == mypgrp (POSIX 4.3.3) 478 */ 479 if (opgrp != shpgrp) 480 if (setpgid(0, shpgrp) == -1) 481 goto notty; 482 /* 483 * We do that after we set our process group, to make sure 484 * that the process group belongs to a process in the same 485 * session as the tty (our process and our group) (POSIX 7.2.4) 486 */ 487 if (tcsetpgrp(f, shpgrp) == -1) 488 goto notty; 489 (void)ioctl(dcopy(f, FSHTTY), FIOCLEX, NULL); 490 } 491 if (tpgrp == -1) { 492 notty: 493 (void)fprintf(csherr, "Warning: no access to tty (%s).\n", 494 strerror(errno)); 495 (void)fprintf(csherr, "Thus no job control in this shell.\n"); 496 } 497 } 498 } 499 if ((setintr == 0) && (parintr == SIG_DFL)) 500 setintr = 1; 501 (void)signal(SIGCHLD, pchild); /* while signals not ready */ 502 503 /* 504 * Set an exit here in case of an interrupt or error reading the shell 505 * start-up scripts. 506 */ 507 reenter = setexit(); /* PWP */ 508 haderr = 0; /* In case second time through */ 509 if (!fast && reenter == 0) { 510 /* Will have value(STRhome) here because set fast if don't */ 511 { 512 sig_t oparintr; 513 sigset_t osigset; 514 int osetintr; 515 516 oparintr = parintr; 517 osetintr = setintr; 518 sigemptyset(&nsigset); 519 (void)sigaddset(&nsigset, SIGINT); 520 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 521 522 setintr = 0; 523 parintr = SIG_IGN; /* Disable onintr */ 524 #ifdef _PATH_DOTCSHRC 525 (void)srcfile(_PATH_DOTCSHRC, 0, 0); 526 #endif 527 if (!fast && !arginp && !onelflg) 528 dohash(NULL, NULL); 529 #ifdef _PATH_DOTLOGIN 530 if (loginsh) 531 (void)srcfile(_PATH_DOTLOGIN, 0, 0); 532 #endif 533 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 534 setintr = osetintr; 535 parintr = oparintr; 536 } 537 (void)srccat(value(STRhome), STRsldotcshrc); 538 539 if (!fast && !arginp && !onelflg && !havhash) 540 dohash(NULL, NULL); 541 /* 542 * Source history before .login so that it is available in .login 543 */ 544 if ((cp = value(STRhistfile)) != STRNULL) 545 tildehist[2] = cp; 546 dosource(tildehist, NULL); 547 if (loginsh) 548 (void)srccat(value(STRhome), STRsldotlogin); 549 } 550 551 /* 552 * Now are ready for the -v and -x flags 553 */ 554 if (nverbose) 555 setNS(STRverbose); 556 if (nexececho) 557 setNS(STRecho); 558 559 /* 560 * All the rest of the world is inside this call. The argument to process 561 * indicates whether it should catch "error unwinds". Thus if we are a 562 * interactive shell our call here will never return by being blown past on 563 * an error. 564 */ 565 process(setintr); 566 567 /* 568 * Mop-up. 569 */ 570 if (intty) { 571 if (loginsh) { 572 (void)fprintf(cshout, "logout\n"); 573 (void)close(SHIN); 574 child = 1; 575 goodbye(); 576 } 577 else { 578 (void)fprintf(cshout, "exit\n"); 579 } 580 } 581 rechist(); 582 exitstat(); 583 /* NOTREACHED */ 584 } 585 586 void 587 untty(void) 588 { 589 if (tpgrp > 0) { 590 (void)setpgid(0, opgrp); 591 (void)tcsetpgrp(FSHTTY, opgrp); 592 } 593 } 594 595 void 596 importpath(Char *cp) 597 { 598 Char *dp, **pv; 599 int c, i; 600 601 i = 0; 602 for (dp = cp; *dp; dp++) 603 if (*dp == ':') 604 i++; 605 /* 606 * i+2 where i is the number of colons in the path. There are i+1 607 * directories in the path plus we need room for a zero terminator. 608 */ 609 pv = (Char **)xcalloc((size_t) (i + 2), sizeof(Char **)); 610 dp = cp; 611 i = 0; 612 if (*dp) 613 for (;;) { 614 if ((c = *dp) == ':' || c == 0) { 615 *dp = 0; 616 pv[i++] = Strsave(*cp ? cp : STRdot); 617 if (c) { 618 cp = dp + 1; 619 *dp = ':'; 620 } 621 else 622 break; 623 } 624 dp++; 625 } 626 pv[i] = 0; 627 setq(STRpath, pv, &shvhed); 628 } 629 630 /* 631 * Source to the file which is the catenation of the argument names. 632 */ 633 static int 634 srccat(Char *cp, Char *dp) 635 { 636 Char *ep; 637 char *ptr; 638 639 ep = Strspl(cp, dp); 640 ptr = short2str(ep); 641 free(ep); 642 return srcfile(ptr, mflag ? 0 : 1, 0); 643 } 644 645 /* 646 * Source to a file putting the file descriptor in a safe place (> 2). 647 */ 648 static int 649 srcfile(const char *f, int onlyown, int flag) 650 { 651 int unit; 652 653 if ((unit = open(f, O_RDONLY)) == -1) 654 return 0; 655 unit = dmove(unit, -1); 656 657 (void) ioctl(unit, FIOCLEX, NULL); 658 srcunit(unit, onlyown, flag); 659 return 1; 660 } 661 662 /* 663 * Source to a unit. If onlyown it must be our file or our group or 664 * we don't chance it. This occurs on ".cshrc"s and the like. 665 */ 666 int insource; 667 668 static void 669 srcunit(int unit, int onlyown, int hflg) 670 { 671 /* We have to push down a lot of state here */ 672 /* All this could go into a structure */ 673 struct whyle *oldwhyl; 674 struct Bin saveB; 675 sigset_t nsigset, osigset; 676 jmp_buf oldexit; 677 Char *oarginp, *oevalp, **oevalvec, *ogointr; 678 Char OHIST; 679 int oSHIN, oinsource, oldintty, oonelflg; 680 int oenterhist, otell; 681 /* The (few) real local variables */ 682 int my_reenter; 683 684 oSHIN = -1; 685 oldintty = intty; 686 oinsource = insource; 687 oldwhyl = whyles; 688 ogointr = gointr; 689 oarginp = arginp; 690 oevalp = evalp; 691 oevalvec = evalvec; 692 oonelflg = onelflg; 693 oenterhist = enterhist; 694 OHIST = HIST; 695 otell = cantell; 696 697 if (unit < 0) 698 return; 699 if (didfds) 700 donefds(); 701 if (onlyown) { 702 struct stat stb; 703 704 if (fstat(unit, &stb) < 0) { 705 (void)close(unit); 706 return; 707 } 708 } 709 710 /* 711 * There is a critical section here while we are pushing down the input 712 * stream since we have stuff in different structures. If we weren't 713 * careful an interrupt could corrupt SHIN's Bin structure and kill the 714 * shell. 715 * 716 * We could avoid the critical region by grouping all the stuff in a single 717 * structure and pointing at it to move it all at once. This is less 718 * efficient globally on many variable references however. 719 */ 720 insource = 1; 721 getexit(oldexit); 722 723 if (setintr) { 724 sigemptyset(&nsigset); 725 (void)sigaddset(&nsigset, SIGINT); 726 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 727 } 728 /* Setup the new values of the state stuff saved above */ 729 (void)memcpy(&saveB, &B, sizeof(B)); 730 fbuf = NULL; 731 fseekp = feobp = fblocks = 0; 732 oSHIN = SHIN, SHIN = unit, arginp = 0, onelflg = 0; 733 intty = isatty(SHIN), whyles = 0, gointr = 0; 734 evalvec = 0; 735 evalp = 0; 736 enterhist = hflg; 737 if (enterhist) 738 HIST = '\0'; 739 740 /* 741 * Now if we are allowing commands to be interrupted, we let ourselves be 742 * interrupted. 743 */ 744 if (setintr) 745 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 746 settell(); 747 748 if ((my_reenter = setexit()) == 0) 749 process(0); /* 0 -> blow away on errors */ 750 751 if (setintr) 752 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 753 if (oSHIN >= 0) { 754 int i; 755 756 /* We made it to the new state... free up its storage */ 757 /* This code could get run twice but free doesn't care */ 758 /* XXX yes it does */ 759 for (i = 0; i < fblocks; i++) 760 free(fbuf[i]); 761 free(fbuf); 762 763 /* Reset input arena */ 764 (void)memcpy(&B, &saveB, sizeof(B)); 765 766 (void)close(SHIN), SHIN = oSHIN; 767 arginp = oarginp, onelflg = oonelflg; 768 evalp = oevalp, evalvec = oevalvec; 769 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 770 if (enterhist) 771 HIST = OHIST; 772 enterhist = oenterhist; 773 cantell = otell; 774 } 775 776 resexit(oldexit); 777 /* 778 * If process reset() (effectively an unwind) then we must also unwind. 779 */ 780 if (my_reenter) 781 stderror(ERR_SILENT); 782 insource = oinsource; 783 } 784 785 void 786 rechist(void) 787 { 788 Char buf[BUFSIZE], hbuf[BUFSIZE], *hfile; 789 int fp, ftmp, oldidfds; 790 struct varent *shist; 791 792 if (!fast) { 793 /* 794 * If $savehist is just set, we use the value of $history 795 * else we use the value in $savehist 796 */ 797 if ((shist = adrof(STRsavehist)) != NULL) { 798 if (shist->vec[0][0] != '\0') 799 (void)Strcpy(hbuf, shist->vec[0]); 800 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 801 (void)Strcpy(hbuf, shist->vec[0]); 802 else 803 return; 804 } 805 else 806 return; 807 808 if ((hfile = value(STRhistfile)) == STRNULL) { 809 hfile = Strcpy(buf, value(STRhome)); 810 (void) Strcat(buf, STRsldthist); 811 } 812 813 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 814 0600)) == -1) 815 return; 816 817 oldidfds = didfds; 818 didfds = 0; 819 ftmp = SHOUT; 820 SHOUT = fp; 821 dumphist[2] = hbuf; 822 dohist(dumphist, NULL); 823 SHOUT = ftmp; 824 (void)close(fp); 825 didfds = oldidfds; 826 } 827 } 828 829 void 830 goodbye(void) 831 { 832 rechist(); 833 834 if (loginsh) { 835 (void)signal(SIGQUIT, SIG_IGN); 836 (void)signal(SIGINT, SIG_IGN); 837 (void)signal(SIGTERM, SIG_IGN); 838 setintr = 0; /* No interrupts after "logout" */ 839 if (!(adrof(STRlogout))) 840 set(STRlogout, STRnormal); 841 #ifdef _PATH_DOTLOGOUT 842 (void)srcfile(_PATH_DOTLOGOUT, 0, 0); 843 #endif 844 if (adrof(STRhome)) 845 (void)srccat(value(STRhome), STRsldtlogout); 846 } 847 exitstat(); 848 /* NOTREACHED */ 849 } 850 851 __dead void 852 exitstat(void) 853 { 854 Char *s; 855 #ifdef PROF 856 monitor(0); 857 #endif 858 /* 859 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 860 * directly because we poke child here. Otherwise we might continue 861 * unwarrantedly (sic). 862 */ 863 child = 1; 864 s = value(STRstatus); 865 xexit(s ? getn(s) : 0); 866 /* NOTREACHED */ 867 } 868 869 /* 870 * in the event of a HUP we want to save the history 871 */ 872 static void 873 phup(int sig) 874 { 875 rechist(); 876 877 /* 878 * We kill the last foreground process group. It then becomes 879 * responsible to propagate the SIGHUP to its progeny. 880 */ 881 { 882 struct process *pp, *np; 883 884 for (pp = proclist.p_next; pp; pp = pp->p_next) { 885 np = pp; 886 /* 887 * Find if this job is in the foreground. It could be that 888 * the process leader has exited and the foreground flag 889 * is cleared for it. 890 */ 891 do 892 /* 893 * If a process is in the foreground; we try to kill 894 * its process group. If we succeed, then the 895 * whole job is gone. Otherwise we keep going... 896 * But avoid sending HUP to the shell again. 897 */ 898 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 899 kill(-np->p_jobid, SIGHUP) != -1) { 900 /* In case the job was suspended... */ 901 (void)kill(-np->p_jobid, SIGCONT); 902 break; 903 } 904 while ((np = np->p_friends) != pp); 905 } 906 } 907 xexit(sig); 908 /* NOTREACHED */ 909 } 910 911 Char *jobargv[2] = {STRjobs, 0}; 912 913 /* 914 * Catch an interrupt, e.g. during lexical input. 915 * If we are an interactive shell, we reset the interrupt catch 916 * immediately. In any case we drain the shell output, 917 * and finally go through the normal error mechanism, which 918 * gets a chance to make the shell go away. 919 */ 920 /* ARGSUSED */ 921 void 922 pintr(int notused) 923 { 924 pintr1(1); 925 /* NOTREACHED */ 926 } 927 928 void 929 pintr1(int wantnl) 930 { 931 Char **v; 932 sigset_t nsigset, osigset; 933 934 sigemptyset(&nsigset); 935 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 936 if (setintr) { 937 nsigset = osigset; 938 (void)sigdelset(&nsigset, SIGINT); 939 (void)sigprocmask(SIG_SETMASK, &nsigset, NULL); 940 if (pjobs) { 941 pjobs = 0; 942 (void)fprintf(cshout, "\n"); 943 dojobs(jobargv, NULL); 944 stderror(ERR_NAME | ERR_INTR); 945 } 946 } 947 (void)sigdelset(&osigset, SIGCHLD); 948 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 949 (void)fpurge(cshout); 950 (void)endpwent(); 951 952 /* 953 * If we have an active "onintr" then we search for the label. Note that if 954 * one does "onintr -" then we shan't be interruptible so we needn't worry 955 * about that here. 956 */ 957 if (gointr) { 958 gotolab(gointr); 959 timflg = 0; 960 if ((v = pargv) != NULL) 961 pargv = 0, blkfree(v); 962 if ((v = gargv) != NULL) 963 gargv = 0, blkfree(v); 964 reset(); 965 } 966 else if (intty && wantnl) { 967 (void)fputc('\r', cshout); 968 (void)fputc('\n', cshout); 969 } 970 stderror(ERR_SILENT); 971 /* NOTREACHED */ 972 } 973 974 /* 975 * Process is the main driving routine for the shell. 976 * It runs all command processing, except for those within { ... } 977 * in expressions (which is run by a routine evalav in sh.exp.c which 978 * is a stripped down process), and `...` evaluation which is run 979 * also by a subset of this code in sh.glob.c in the routine backeval. 980 * 981 * The code here is a little strange because part of it is interruptible 982 * and hence freeing of structures appears to occur when none is necessary 983 * if this is ignored. 984 * 985 * Note that if catch is not set then we will unwind on any error. 986 * If an end-of-file occurs, we return. 987 */ 988 static struct command *savet = NULL; 989 990 void 991 process(int catch) 992 { 993 struct command *t; 994 jmp_buf osetexit; 995 sigset_t nsigset; 996 997 t = savet; 998 savet = NULL; 999 getexit(osetexit); 1000 for (;;) { 1001 pendjob(); 1002 paraml.next = paraml.prev = ¶ml; 1003 paraml.word = STRNULL; 1004 (void)setexit(); 1005 justpr = enterhist; /* execute if not entering history */ 1006 1007 /* 1008 * Interruptible during interactive reads 1009 */ 1010 if (setintr) { 1011 sigemptyset(&nsigset); 1012 (void)sigaddset(&nsigset, SIGINT); 1013 (void)sigprocmask(SIG_UNBLOCK, &nsigset, NULL); 1014 } 1015 1016 /* 1017 * For the sake of reset() 1018 */ 1019 freelex(¶ml); 1020 if (savet) 1021 freesyn(savet), savet = NULL; 1022 1023 if (haderr) { 1024 if (!catch) { 1025 /* unwind */ 1026 doneinp = 0; 1027 resexit(osetexit); 1028 savet = t; 1029 reset(); 1030 } 1031 haderr = 0; 1032 /* 1033 * Every error is eventually caught here or the shell dies. It is 1034 * at this point that we clean up any left-over open files, by 1035 * closing all but a fixed number of pre-defined files. Thus 1036 * routines don't have to worry about leaving files open due to 1037 * deeper errors... they will get closed here. 1038 */ 1039 closem(); 1040 continue; 1041 } 1042 if (doneinp) { 1043 doneinp = 0; 1044 break; 1045 } 1046 if (chkstop) 1047 chkstop--; 1048 if (neednote) 1049 pnote(); 1050 if (intty && prompt && evalvec == 0) { 1051 mailchk(); 1052 /* 1053 * If we are at the end of the input buffer then we are going to 1054 * read fresh stuff. Otherwise, we are rereading input and don't 1055 * need or want to prompt. 1056 */ 1057 if (aret == F_SEEK && fseekp == feobp) 1058 printprompt(); 1059 (void)fflush(cshout); 1060 } 1061 if (seterr) { 1062 free(seterr); 1063 seterr = NULL; 1064 } 1065 1066 /* 1067 * Echo not only on VERBOSE, but also with history expansion. If there 1068 * is a lexical error then we forego history echo. 1069 */ 1070 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1071 int odidfds = didfds; 1072 fflush(csherr); 1073 didfds = 0; 1074 prlex(csherr, ¶ml); 1075 fflush(csherr); 1076 didfds = odidfds; 1077 } 1078 1079 /* 1080 * The parser may lose space if interrupted. 1081 */ 1082 if (setintr) 1083 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 1084 1085 /* 1086 * Save input text on the history list if reading in old history, or it 1087 * is from the terminal at the top level and not in a loop. 1088 * 1089 * PWP: entry of items in the history list while in a while loop is done 1090 * elsewhere... 1091 */ 1092 if (enterhist || (catch && intty && !whyles)) 1093 savehist(¶ml); 1094 1095 /* 1096 * Print lexical error messages, except when sourcing history lists. 1097 */ 1098 if (!enterhist && seterr) 1099 stderror(ERR_OLD); 1100 1101 /* 1102 * If had a history command :p modifier then this is as far as we 1103 * should go 1104 */ 1105 if (justpr) 1106 reset(); 1107 1108 alias(¶ml); 1109 1110 /* 1111 * Parse the words of the input into a parse tree. 1112 */ 1113 savet = syntax(paraml.next, ¶ml, 0); 1114 if (seterr) 1115 stderror(ERR_OLD); 1116 1117 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1118 1119 /* 1120 * Made it! 1121 */ 1122 freelex(¶ml); 1123 freesyn((struct command *) savet), savet = NULL; 1124 } 1125 resexit(osetexit); 1126 savet = t; 1127 } 1128 1129 void 1130 /*ARGSUSED*/ 1131 dosource(Char **v, struct command *t) 1132 { 1133 Char buf[BUFSIZE], *f; 1134 int hflg; 1135 1136 hflg = 0; 1137 v++; 1138 if (*v && eq(*v, STRmh)) { 1139 if (*++v == NULL) 1140 stderror(ERR_NAME | ERR_HFLAG); 1141 hflg++; 1142 } 1143 (void)Strcpy(buf, *v); 1144 f = globone(buf, G_ERROR); 1145 (void)strcpy((char *)buf, short2str(f)); 1146 free(f); 1147 if (!srcfile((char *)buf, 0, hflg) && !hflg) 1148 stderror(ERR_SYSTEM, (char *)buf, strerror(errno)); 1149 } 1150 1151 /* 1152 * Check for mail. 1153 * If we are a login shell, then we don't want to tell 1154 * about any mail file unless its been modified 1155 * after the time we started. 1156 * This prevents us from telling the user things he already 1157 * knows, since the login program insists on saying 1158 * "You have mail." 1159 */ 1160 static void 1161 mailchk(void) 1162 { 1163 struct stat stb; 1164 struct varent *v; 1165 Char **vp; 1166 time_t t; 1167 int cnt, intvl; 1168 int new; 1169 1170 v = adrof(STRmail); 1171 if (v == 0) 1172 return; 1173 (void)time(&t); 1174 vp = v->vec; 1175 cnt = blklen(vp); 1176 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1177 if (intvl < 1) 1178 intvl = 1; 1179 if (chktim + intvl > t) 1180 return; 1181 for (; *vp; vp++) { 1182 if (stat(short2str(*vp), &stb) < 0) 1183 continue; 1184 new = stb.st_mtime > time0.tv_sec; 1185 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1186 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1187 (loginsh && !new)) 1188 continue; 1189 if (cnt == 1) 1190 (void)fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1191 else 1192 (void)fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1193 vis_str(*vp)); 1194 } 1195 chktim = t; 1196 } 1197 1198 /* 1199 * Extract a home directory from the password file 1200 * The argument points to a buffer where the name of the 1201 * user whose home directory is sought is currently. 1202 * We write the home directory of the user back there. 1203 */ 1204 int 1205 gethdir(Char *home) 1206 { 1207 struct passwd *pw; 1208 Char *h; 1209 1210 /* 1211 * Is it us? 1212 */ 1213 if (*home == '\0') { 1214 if ((h = value(STRhome)) != NULL) { 1215 (void)Strcpy(home, h); 1216 return 0; 1217 } 1218 else 1219 return 1; 1220 } 1221 1222 if ((pw = getpwnam(short2str(home))) != NULL) { 1223 (void)Strcpy(home, str2short(pw->pw_dir)); 1224 return 0; 1225 } 1226 else 1227 return 1; 1228 } 1229 1230 /* 1231 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1232 * We also check if the shell has already changed the descriptor to point to 1233 * 0, 1, 2 when didfds is set. 1234 */ 1235 #define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1236 1237 static ssize_t 1238 readf(void *oreo, void *buf, size_t siz) 1239 { 1240 return read(DESC(oreo), buf, siz); 1241 } 1242 1243 1244 static ssize_t 1245 writef(void *oreo, const void *buf, size_t siz) 1246 { 1247 return write(DESC(oreo), buf, siz); 1248 } 1249 1250 static off_t 1251 seekf(void *oreo, off_t off, int whence) 1252 { 1253 return lseek(DESC(oreo), off, whence); 1254 } 1255 1256 1257 static int 1258 closef(void *oreo) 1259 { 1260 return close(DESC(oreo)); 1261 } 1262 1263 1264 /* 1265 * Print the visible version of a string. 1266 */ 1267 int 1268 vis_fputc(int ch, FILE *fp) 1269 { 1270 char uenc[5]; /* 4 + NULL */ 1271 1272 if (ch & QUOTE) 1273 return fputc(ch & TRIM, fp); 1274 /* 1275 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1276 * be encoded, but currently there is no way in vis to do that. 1277 */ 1278 (void)vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1279 return (fputs(uenc, fp)); 1280 } 1281 1282 /* 1283 * Move the initial descriptors to their eventual 1284 * resting places, closing all other units. 1285 */ 1286 void 1287 initdesc(void) 1288 { 1289 didfds = 0; /* 0, 1, 2 aren't set up */ 1290 (void)ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1291 (void)ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1292 (void)ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1293 (void)ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1294 closem(); 1295 } 1296 1297 1298 __dead void 1299 #ifdef PROF 1300 done(int i) 1301 #else 1302 xexit(int i) 1303 #endif 1304 { 1305 untty(); 1306 _exit(i); 1307 /* NOTREACHED */ 1308 } 1309 1310 #ifndef _PATH_DEFPATH 1311 static Char ** 1312 defaultpath(void) 1313 { 1314 struct stat stb; 1315 Char **blk, **blkp; 1316 char *ptr; 1317 1318 blkp = blk = xmalloc((size_t) sizeof(Char *) * 10); 1319 1320 #define DIRAPPEND(a) \ 1321 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1322 *blkp++ = SAVE(ptr) 1323 #ifdef RESCUEDIR 1324 DIRAPPEND(RESCUEDIR); 1325 #endif 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 (editing) 1347 return; 1348 1349 if (!whyles) { 1350 for (cp = value(STRprompt); *cp; cp++) 1351 if (*cp == HIST) 1352 (void)fprintf(cshout, "%d", eventno + 1); 1353 else { 1354 if (*cp == '\\' && cp[1] == HIST) 1355 cp++; 1356 (void)vis_fputc(*cp | QUOTE, cshout); 1357 } 1358 } 1359 else 1360 /* 1361 * Prompt for forward reading loop body content. 1362 */ 1363 (void)fprintf(cshout, "? "); 1364 (void)fflush(cshout); 1365 } 1366 1367 #ifdef EDIT 1368 char * 1369 printpromptstr(EditLine *elx) { 1370 static char pbuf[1024]; 1371 static char qspace[] = "? "; 1372 Char *cp; 1373 size_t i; 1374 1375 if (whyles) 1376 return qspace; 1377 1378 i = 0; 1379 for (cp = value(STRprompt); *cp; cp++) { 1380 if (i >= sizeof(pbuf)) 1381 break; 1382 if (*cp == HIST) { 1383 int r; 1384 r = snprintf(pbuf + i, sizeof(pbuf) - i, "%d", eventno + 1); 1385 if (r > 0) 1386 i += (size_t)r; 1387 } else 1388 pbuf[i++] = (char)*cp; 1389 } 1390 if (i >= sizeof(pbuf)) 1391 i = sizeof(pbuf) - 1; 1392 pbuf[i] = '\0'; 1393 return pbuf; 1394 } 1395 #endif 1396