1 /* $NetBSD: csh.c,v 1.48 2019/01/05 16:54:00 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 1.48 2019/01/05 16:54:00 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 #ifdef EDITING 109 int editing = 0; 110 #endif 111 112 int 113 main(int argc, char *argv[]) 114 { 115 struct sigaction oact; 116 Char *cp; 117 char *tcp, **tempv; 118 const char *ecp; 119 sigset_t nsigset; 120 int f; 121 122 cshin = stdin; 123 cshout = stdout; 124 csherr = stderr; 125 126 setprogname(argv[0]); 127 settimes(); /* Immed. estab. timing base */ 128 129 /* 130 * Initialize non constant strings 131 */ 132 #ifdef _PATH_BSHELL 133 STR_BSHELL = SAVE(_PATH_BSHELL); 134 #endif 135 #ifdef _PATH_CSHELL 136 STR_SHELLPATH = SAVE(_PATH_CSHELL); 137 #endif 138 STR_environ = blk2short(environ); 139 environ = short2blk(STR_environ); /* So that we can free it */ 140 STR_WORD_CHARS = SAVE(WORD_CHARS); 141 142 HIST = '!'; 143 HISTSUB = '^'; 144 word_chars = STR_WORD_CHARS; 145 146 tempv = argv; 147 if (eq(str2short(tempv[0]), STRaout)) /* A.out's are quittable */ 148 quitit = 1; 149 uid = getuid(); 150 gid = getgid(); 151 euid = geteuid(); 152 egid = getegid(); 153 /* 154 * We are a login shell if: 1. we were invoked as -<something> and we had 155 * no arguments 2. or we were invoked only with the -l flag 156 */ 157 loginsh = (**tempv == '-' && argc == 1) || 158 (argc == 2 && tempv[1][0] == '-' && tempv[1][1] == 'l' && 159 tempv[1][2] == '\0'); 160 161 if (loginsh && **tempv != '-') { 162 /* 163 * Mangle the argv space 164 */ 165 tempv[1][0] = '\0'; 166 tempv[1][1] = '\0'; 167 tempv[1] = NULL; 168 for (tcp = *tempv; *tcp++;) 169 continue; 170 for (tcp--; tcp >= *tempv; tcp--) 171 tcp[1] = tcp[0]; 172 *++tcp = '-'; 173 argc--; 174 } 175 if (loginsh) 176 (void)time(&chktim); 177 178 AsciiOnly = 1; 179 #ifdef NLS 180 (void)setlocale(LC_ALL, ""); 181 { 182 int k; 183 184 for (k = 0200; k <= 0377 && !Isprint(k); k++) 185 continue; 186 AsciiOnly = k > 0377; 187 } 188 #else 189 AsciiOnly = getenv("LANG") == NULL && getenv("LC_CTYPE") == NULL; 190 #endif /* NLS */ 191 192 /* 193 * Move the descriptors to safe places. The variable didfds is 0 while we 194 * have only FSH* to work with. When didfds is true, we have 0,1,2 and 195 * prefer to use these. 196 */ 197 initdesc(); 198 /* 199 * XXX: This is to keep programs that use stdio happy. 200 * what we really want is freunopen() .... 201 * Closing cshin cshout and csherr (which are really stdin stdout 202 * and stderr at this point and then reopening them in the same order 203 * gives us again stdin == cshin stdout == cshout and stderr == csherr. 204 * If that was not the case builtins like printf that use stdio 205 * would break. But in any case we could fix that with memcpy and 206 * a bit of pointer manipulation... 207 * Fortunately this is not needed under the current implementation 208 * of stdio. 209 */ 210 (void)fclose(cshin); 211 (void)fclose(cshout); 212 (void)fclose(csherr); 213 if (!(cshin = funopen2((void *) &SHIN, readf, writef, seekf, NULL, 214 closef))) 215 exit(1); 216 if (!(cshout = funopen2((void *) &SHOUT, readf, writef, seekf, NULL, 217 closef))) 218 exit(1); 219 if (!(csherr = funopen2((void *) &SHERR, readf, writef, seekf, NULL, 220 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(&nsigset); 448 (void)sigaddset(&nsigset, SIGINT); 449 (void)sigprocmask(SIG_BLOCK, &nsigset, 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(&nsigset); 522 (void)sigaddset(&nsigset, SIGINT); 523 (void)sigprocmask(SIG_BLOCK, &nsigset, &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 tildehist[2] = cp; 549 dosource(tildehist, 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 free(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(const char *f, int onlyown, int 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, int onlyown, int 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 nsigset, osigset; 679 jmp_buf oldexit; 680 Char *oarginp, *oevalp, **oevalvec, *ogointr; 681 Char OHIST; 682 int oSHIN, oinsource, oldintty, oonelflg; 683 int 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(&nsigset); 728 (void)sigaddset(&nsigset, SIGINT); 729 (void)sigprocmask(SIG_BLOCK, &nsigset, &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 free doesn't care */ 761 /* XXX yes it does */ 762 for (i = 0; i < fblocks; i++) 763 free(fbuf[i]); 764 free(fbuf); 765 766 /* Reset input arena */ 767 (void)memcpy(&B, &saveB, sizeof(B)); 768 769 (void)close(SHIN), SHIN = oSHIN; 770 arginp = oarginp, onelflg = oonelflg; 771 evalp = oevalp, evalvec = oevalvec; 772 intty = oldintty, whyles = oldwhyl, gointr = ogointr; 773 if (enterhist) 774 HIST = OHIST; 775 enterhist = oenterhist; 776 cantell = otell; 777 } 778 779 resexit(oldexit); 780 /* 781 * If process reset() (effectively an unwind) then we must also unwind. 782 */ 783 if (my_reenter) 784 stderror(ERR_SILENT); 785 insource = oinsource; 786 } 787 788 void 789 rechist(void) 790 { 791 Char buf[BUFSIZE], hbuf[BUFSIZE], *hfile; 792 int fp, ftmp, oldidfds; 793 struct varent *shist; 794 795 if (!fast) { 796 /* 797 * If $savehist is just set, we use the value of $history 798 * else we use the value in $savehist 799 */ 800 if ((shist = adrof(STRsavehist)) != NULL) { 801 if (shist->vec[0][0] != '\0') 802 (void)Strcpy(hbuf, shist->vec[0]); 803 else if ((shist = adrof(STRhistory)) && shist->vec[0][0] != '\0') 804 (void)Strcpy(hbuf, shist->vec[0]); 805 else 806 return; 807 } 808 else 809 return; 810 811 if ((hfile = value(STRhistfile)) == STRNULL) { 812 hfile = Strcpy(buf, value(STRhome)); 813 (void) Strcat(buf, STRsldthist); 814 } 815 816 if ((fp = open(short2str(hfile), O_WRONLY | O_CREAT | O_TRUNC, 817 0600)) == -1) 818 return; 819 820 oldidfds = didfds; 821 didfds = 0; 822 ftmp = SHOUT; 823 SHOUT = fp; 824 dumphist[2] = hbuf; 825 dohist(dumphist, NULL); 826 SHOUT = ftmp; 827 (void)close(fp); 828 didfds = oldidfds; 829 } 830 } 831 832 void 833 goodbye(void) 834 { 835 rechist(); 836 837 if (loginsh) { 838 (void)signal(SIGQUIT, SIG_IGN); 839 (void)signal(SIGINT, SIG_IGN); 840 (void)signal(SIGTERM, SIG_IGN); 841 setintr = 0; /* No interrupts after "logout" */ 842 if (!(adrof(STRlogout))) 843 set(STRlogout, STRnormal); 844 #ifdef _PATH_DOTLOGOUT 845 (void)srcfile(_PATH_DOTLOGOUT, 0, 0); 846 #endif 847 if (adrof(STRhome)) 848 (void)srccat(value(STRhome), STRsldtlogout); 849 } 850 exitstat(); 851 /* NOTREACHED */ 852 } 853 854 __dead void 855 exitstat(void) 856 { 857 Char *s; 858 #ifdef PROF 859 monitor(0); 860 #endif 861 /* 862 * Note that if STATUS is corrupted (i.e. getn bombs) then error will exit 863 * directly because we poke child here. Otherwise we might continue 864 * unwarrantedly (sic). 865 */ 866 child = 1; 867 s = value(STRstatus); 868 xexit(s ? getn(s) : 0); 869 /* NOTREACHED */ 870 } 871 872 /* 873 * in the event of a HUP we want to save the history 874 */ 875 static void 876 phup(int sig) 877 { 878 rechist(); 879 880 /* 881 * We kill the last foreground process group. It then becomes 882 * responsible to propagate the SIGHUP to its progeny. 883 */ 884 { 885 struct process *pp, *np; 886 887 for (pp = proclist.p_next; pp; pp = pp->p_next) { 888 np = pp; 889 /* 890 * Find if this job is in the foreground. It could be that 891 * the process leader has exited and the foreground flag 892 * is cleared for it. 893 */ 894 do 895 /* 896 * If a process is in the foreground; we try to kill 897 * its process group. If we succeed, then the 898 * whole job is gone. Otherwise we keep going... 899 * But avoid sending HUP to the shell again. 900 */ 901 if ((np->p_flags & PFOREGND) != 0 && np->p_jobid != shpgrp && 902 kill(-np->p_jobid, SIGHUP) != -1) { 903 /* In case the job was suspended... */ 904 (void)kill(-np->p_jobid, SIGCONT); 905 break; 906 } 907 while ((np = np->p_friends) != pp); 908 } 909 } 910 xexit(sig); 911 /* NOTREACHED */ 912 } 913 914 Char *jobargv[2] = {STRjobs, 0}; 915 916 /* 917 * Catch an interrupt, e.g. during lexical input. 918 * If we are an interactive shell, we reset the interrupt catch 919 * immediately. In any case we drain the shell output, 920 * and finally go through the normal error mechanism, which 921 * gets a chance to make the shell go away. 922 */ 923 /* ARGSUSED */ 924 void 925 pintr(int notused) 926 { 927 pintr1(1); 928 /* NOTREACHED */ 929 } 930 931 void 932 pintr1(int wantnl) 933 { 934 Char **v; 935 sigset_t nsigset, osigset; 936 937 sigemptyset(&nsigset); 938 (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset); 939 if (setintr) { 940 nsigset = osigset; 941 (void)sigdelset(&nsigset, SIGINT); 942 (void)sigprocmask(SIG_SETMASK, &nsigset, NULL); 943 if (pjobs) { 944 pjobs = 0; 945 (void)fprintf(cshout, "\n"); 946 dojobs(jobargv, NULL); 947 stderror(ERR_NAME | ERR_INTR); 948 } 949 } 950 (void)sigdelset(&osigset, SIGCHLD); 951 (void)sigprocmask(SIG_SETMASK, &osigset, NULL); 952 (void)fpurge(cshout); 953 (void)endpwent(); 954 955 /* 956 * If we have an active "onintr" then we search for the label. Note that if 957 * one does "onintr -" then we shan't be interruptible so we needn't worry 958 * about that here. 959 */ 960 if (gointr) { 961 gotolab(gointr); 962 timflg = 0; 963 if ((v = pargv) != NULL) 964 pargv = 0, blkfree(v); 965 if ((v = gargv) != NULL) 966 gargv = 0, blkfree(v); 967 reset(); 968 } 969 else if (intty && wantnl) { 970 (void)fputc('\r', cshout); 971 (void)fputc('\n', cshout); 972 } 973 stderror(ERR_SILENT); 974 /* NOTREACHED */ 975 } 976 977 /* 978 * Process is the main driving routine for the shell. 979 * It runs all command processing, except for those within { ... } 980 * in expressions (which is run by a routine evalav in sh.exp.c which 981 * is a stripped down process), and `...` evaluation which is run 982 * also by a subset of this code in sh.glob.c in the routine backeval. 983 * 984 * The code here is a little strange because part of it is interruptible 985 * and hence freeing of structures appears to occur when none is necessary 986 * if this is ignored. 987 * 988 * Note that if catch is not set then we will unwind on any error. 989 * If an end-of-file occurs, we return. 990 */ 991 static struct command *savet = NULL; 992 993 void 994 process(int catch) 995 { 996 struct command *t; 997 jmp_buf osetexit; 998 sigset_t nsigset; 999 1000 t = savet; 1001 savet = NULL; 1002 getexit(osetexit); 1003 for (;;) { 1004 pendjob(); 1005 paraml.next = paraml.prev = ¶ml; 1006 paraml.word = STRNULL; 1007 (void)setexit(); 1008 justpr = enterhist; /* execute if not entering history */ 1009 1010 /* 1011 * Interruptible during interactive reads 1012 */ 1013 if (setintr) { 1014 sigemptyset(&nsigset); 1015 (void)sigaddset(&nsigset, SIGINT); 1016 (void)sigprocmask(SIG_UNBLOCK, &nsigset, NULL); 1017 } 1018 1019 /* 1020 * For the sake of reset() 1021 */ 1022 freelex(¶ml); 1023 if (savet) 1024 freesyn(savet), savet = NULL; 1025 1026 if (haderr) { 1027 if (!catch) { 1028 /* unwind */ 1029 doneinp = 0; 1030 resexit(osetexit); 1031 savet = t; 1032 reset(); 1033 } 1034 haderr = 0; 1035 /* 1036 * Every error is eventually caught here or the shell dies. It is 1037 * at this point that we clean up any left-over open files, by 1038 * closing all but a fixed number of pre-defined files. Thus 1039 * routines don't have to worry about leaving files open due to 1040 * deeper errors... they will get closed here. 1041 */ 1042 closem(); 1043 continue; 1044 } 1045 if (doneinp) { 1046 doneinp = 0; 1047 break; 1048 } 1049 if (chkstop) 1050 chkstop--; 1051 if (neednote) 1052 pnote(); 1053 if (intty && prompt && evalvec == 0) { 1054 mailchk(); 1055 /* 1056 * If we are at the end of the input buffer then we are going to 1057 * read fresh stuff. Otherwise, we are rereading input and don't 1058 * need or want to prompt. 1059 */ 1060 if (aret == F_SEEK && fseekp == feobp) 1061 printprompt(); 1062 (void)fflush(cshout); 1063 } 1064 if (seterr) { 1065 free(seterr); 1066 seterr = NULL; 1067 } 1068 1069 /* 1070 * Echo not only on VERBOSE, but also with history expansion. If there 1071 * is a lexical error then we forego history echo. 1072 */ 1073 if ((lex(¶ml) && !seterr && intty) || adrof(STRverbose)) { 1074 int odidfds = didfds; 1075 fflush(csherr); 1076 didfds = 0; 1077 prlex(csherr, ¶ml); 1078 fflush(csherr); 1079 didfds = odidfds; 1080 } 1081 1082 /* 1083 * The parser may lose space if interrupted. 1084 */ 1085 if (setintr) 1086 (void)sigprocmask(SIG_BLOCK, &nsigset, NULL); 1087 1088 /* 1089 * Save input text on the history list if reading in old history, or it 1090 * is from the terminal at the top level and not in a loop. 1091 * 1092 * PWP: entry of items in the history list while in a while loop is done 1093 * elsewhere... 1094 */ 1095 if (enterhist || (catch && intty && !whyles)) 1096 savehist(¶ml); 1097 1098 /* 1099 * Print lexical error messages, except when sourcing history lists. 1100 */ 1101 if (!enterhist && seterr) 1102 stderror(ERR_OLD); 1103 1104 /* 1105 * If had a history command :p modifier then this is as far as we 1106 * should go 1107 */ 1108 if (justpr) 1109 reset(); 1110 1111 alias(¶ml); 1112 1113 /* 1114 * Parse the words of the input into a parse tree. 1115 */ 1116 savet = syntax(paraml.next, ¶ml, 0); 1117 if (seterr) 1118 stderror(ERR_OLD); 1119 1120 execute(savet, (tpgrp > 0 ? tpgrp : -1), NULL, NULL); 1121 1122 /* 1123 * Made it! 1124 */ 1125 freelex(¶ml); 1126 freesyn((struct command *) savet), savet = NULL; 1127 } 1128 resexit(osetexit); 1129 savet = t; 1130 } 1131 1132 void 1133 /*ARGSUSED*/ 1134 dosource(Char **v, struct command *t) 1135 { 1136 Char buf[BUFSIZE], *f; 1137 int hflg; 1138 1139 hflg = 0; 1140 v++; 1141 if (*v && eq(*v, STRmh)) { 1142 if (*++v == NULL) 1143 stderror(ERR_NAME | ERR_HFLAG); 1144 hflg++; 1145 } 1146 (void)Strcpy(buf, *v); 1147 f = globone(buf, G_ERROR); 1148 (void)strcpy((char *)buf, short2str(f)); 1149 free(f); 1150 if (!srcfile((char *)buf, 0, hflg) && !hflg) 1151 stderror(ERR_SYSTEM, (char *)buf, strerror(errno)); 1152 } 1153 1154 /* 1155 * Check for mail. 1156 * If we are a login shell, then we don't want to tell 1157 * about any mail file unless its been modified 1158 * after the time we started. 1159 * This prevents us from telling the user things he already 1160 * knows, since the login program insists on saying 1161 * "You have mail." 1162 */ 1163 static void 1164 mailchk(void) 1165 { 1166 struct stat stb; 1167 struct varent *v; 1168 Char **vp; 1169 time_t t; 1170 int cnt, intvl; 1171 int new; 1172 1173 v = adrof(STRmail); 1174 if (v == 0) 1175 return; 1176 (void)time(&t); 1177 vp = v->vec; 1178 cnt = blklen(vp); 1179 intvl = (cnt && number(*vp)) ? (--cnt, getn(*vp++)) : MAILINTVL; 1180 if (intvl < 1) 1181 intvl = 1; 1182 if (chktim + intvl > t) 1183 return; 1184 for (; *vp; vp++) { 1185 if (stat(short2str(*vp), &stb) < 0) 1186 continue; 1187 new = stb.st_mtime > time0.tv_sec; 1188 if (stb.st_size == 0 || stb.st_atime > stb.st_mtime || 1189 (stb.st_atime < chktim && stb.st_mtime < chktim) || 1190 (loginsh && !new)) 1191 continue; 1192 if (cnt == 1) 1193 (void)fprintf(cshout, "You have %smail.\n", new ? "new " : ""); 1194 else 1195 (void)fprintf(cshout, "%s in %s.\n", new ? "New mail" : "Mail", 1196 vis_str(*vp)); 1197 } 1198 chktim = t; 1199 } 1200 1201 /* 1202 * Extract a home directory from the password file 1203 * The argument points to a buffer where the name of the 1204 * user whose home directory is sought is currently. 1205 * We write the home directory of the user back there. 1206 */ 1207 int 1208 gethdir(Char *home) 1209 { 1210 struct passwd *pw; 1211 Char *h; 1212 1213 /* 1214 * Is it us? 1215 */ 1216 if (*home == '\0') { 1217 if ((h = value(STRhome)) != NULL) { 1218 (void)Strcpy(home, h); 1219 return 0; 1220 } 1221 else 1222 return 1; 1223 } 1224 1225 if ((pw = getpwnam(short2str(home))) != NULL) { 1226 (void)Strcpy(home, str2short(pw->pw_dir)); 1227 return 0; 1228 } 1229 else 1230 return 1; 1231 } 1232 1233 /* 1234 * When didfds is set, we do I/O from 0, 1, 2 otherwise from 15, 16, 17 1235 * We also check if the shell has already changed the descriptor to point to 1236 * 0, 1, 2 when didfds is set. 1237 */ 1238 #define DESC(a) (*((int *) (a)) - (didfds && *((int *) a) >= FSHIN ? FSHIN : 0)) 1239 1240 static ssize_t 1241 readf(void *oreo, void *buf, size_t siz) 1242 { 1243 return read(DESC(oreo), buf, siz); 1244 } 1245 1246 1247 static ssize_t 1248 writef(void *oreo, const void *buf, size_t siz) 1249 { 1250 return write(DESC(oreo), buf, siz); 1251 } 1252 1253 static off_t 1254 seekf(void *oreo, off_t off, int whence) 1255 { 1256 return lseek(DESC(oreo), off, whence); 1257 } 1258 1259 1260 static int 1261 closef(void *oreo) 1262 { 1263 return close(DESC(oreo)); 1264 } 1265 1266 1267 /* 1268 * Print the visible version of a string. 1269 */ 1270 int 1271 vis_fputc(int ch, FILE *fp) 1272 { 1273 char uenc[5]; /* 4 + NULL */ 1274 1275 if (ch & QUOTE) 1276 return fputc(ch & TRIM, fp); 1277 /* 1278 * XXX: When we are in AsciiOnly we want all characters >= 0200 to 1279 * be encoded, but currently there is no way in vis to do that. 1280 */ 1281 (void)vis(uenc, ch & TRIM, VIS_NOSLASH, 0); 1282 return (fputs(uenc, fp)); 1283 } 1284 1285 /* 1286 * Move the initial descriptors to their eventual 1287 * resting places, closing all other units. 1288 */ 1289 void 1290 initdesc(void) 1291 { 1292 didfds = 0; /* 0, 1, 2 aren't set up */ 1293 (void)ioctl(SHIN = dcopy(0, FSHIN), FIOCLEX, NULL); 1294 (void)ioctl(SHOUT = dcopy(1, FSHOUT), FIOCLEX, NULL); 1295 (void)ioctl(SHERR = dcopy(2, FSHERR), FIOCLEX, NULL); 1296 (void)ioctl(OLDSTD = dcopy(SHIN, FOLDSTD), FIOCLEX, NULL); 1297 closem(); 1298 } 1299 1300 1301 __dead void 1302 #ifdef PROF 1303 done(int i) 1304 #else 1305 xexit(int i) 1306 #endif 1307 { 1308 untty(); 1309 _exit(i); 1310 /* NOTREACHED */ 1311 } 1312 1313 #ifndef _PATH_DEFPATH 1314 static Char ** 1315 defaultpath(void) 1316 { 1317 struct stat stb; 1318 Char **blk, **blkp; 1319 char *ptr; 1320 1321 blkp = blk = xmalloc((size_t) sizeof(Char *) * 10); 1322 1323 #define DIRAPPEND(a) \ 1324 if (stat(ptr = a, &stb) == 0 && S_ISDIR(stb.st_mode)) \ 1325 *blkp++ = SAVE(ptr) 1326 #ifdef RESCUEDIR 1327 DIRAPPEND(RESCUEDIR); 1328 #endif 1329 DIRAPPEND(_PATH_BIN); 1330 DIRAPPEND(_PATH_USRBIN); 1331 1332 #undef DIRAPPEND 1333 1334 #if 0 1335 if (euid != 0 && uid != 0) 1336 *blkp++ = Strsave(STRdot); 1337 #endif 1338 1339 *blkp = NULL; 1340 return (blk); 1341 } 1342 #endif /* _PATH_DEFPATH */ 1343 1344 void 1345 printprompt(void) 1346 { 1347 Char *cp; 1348 1349 if (editing) 1350 return; 1351 1352 if (!whyles) { 1353 for (cp = value(STRprompt); *cp; cp++) 1354 if (*cp == HIST) 1355 (void)fprintf(cshout, "%d", eventno + 1); 1356 else { 1357 if (*cp == '\\' && cp[1] == HIST) 1358 cp++; 1359 (void)vis_fputc(*cp | QUOTE, cshout); 1360 } 1361 } 1362 else 1363 /* 1364 * Prompt for forward reading loop body content. 1365 */ 1366 (void)fprintf(cshout, "? "); 1367 (void)fflush(cshout); 1368 } 1369 1370 #ifdef EDIT 1371 char * 1372 printpromptstr(EditLine *elx) { 1373 static char pbuf[1024]; 1374 static char qspace[] = "? "; 1375 Char *cp; 1376 size_t i; 1377 1378 if (whyles) 1379 return qspace; 1380 1381 i = 0; 1382 for (cp = value(STRprompt); *cp; cp++) { 1383 if (i >= sizeof(pbuf)) 1384 break; 1385 if (*cp == HIST) { 1386 int r; 1387 r = snprintf(pbuf + i, sizeof(pbuf) - i, "%d", eventno + 1); 1388 if (r > 0) 1389 i += (size_t)r; 1390 } else 1391 pbuf[i++] = (char)*cp; 1392 } 1393 if (i >= sizeof(pbuf)) 1394 i = sizeof(pbuf) - 1; 1395 pbuf[i] = '\0'; 1396 return pbuf; 1397 } 1398 #endif 1399