1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #ifndef lint 34 #if 0 35 static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 36 #endif 37 #endif /* not lint */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <fcntl.h> 42 #include <signal.h> 43 #include <errno.h> 44 #include <paths.h> 45 #include <unistd.h> 46 #include <stdlib.h> 47 #include <sys/param.h> 48 #include <sys/wait.h> 49 #include <sys/time.h> 50 #include <sys/resource.h> 51 #include <paths.h> 52 #include <sys/ioctl.h> 53 54 #include "shell.h" 55 #if JOBS 56 #include <termios.h> 57 #undef CEOF /* syntax.h redefines this */ 58 #endif 59 #include "redir.h" 60 #include "show.h" 61 #include "main.h" 62 #include "parser.h" 63 #include "nodes.h" 64 #include "jobs.h" 65 #include "options.h" 66 #include "trap.h" 67 #include "syntax.h" 68 #include "input.h" 69 #include "output.h" 70 #include "memalloc.h" 71 #include "error.h" 72 #include "mystring.h" 73 74 75 STATIC struct job *jobtab; /* array of jobs */ 76 STATIC int njobs; /* size of array */ 77 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 78 #if JOBS 79 STATIC struct job *jobmru; /* most recently used job list */ 80 STATIC pid_t initialpgrp; /* pgrp of shell on invocation */ 81 #endif 82 int in_waitcmd = 0; /* are we in waitcmd()? */ 83 int in_dowait = 0; /* are we in dowait()? */ 84 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 85 static int ttyfd = -1; 86 87 #if JOBS 88 STATIC void restartjob(struct job *); 89 #endif 90 STATIC void freejob(struct job *); 91 STATIC struct job *getjob(char *); 92 STATIC pid_t dowait(int, struct job *); 93 STATIC pid_t waitproc(int, int *); 94 STATIC void checkzombies(void); 95 STATIC void cmdtxt(union node *); 96 STATIC void cmdputs(const char *); 97 #if JOBS 98 STATIC void setcurjob(struct job *); 99 STATIC void deljob(struct job *); 100 STATIC struct job *getcurjob(struct job *); 101 #endif 102 STATIC void showjob(struct job *, pid_t, int); 103 104 105 /* 106 * Turn job control on and off. 107 */ 108 109 MKINIT int jobctl; 110 111 #if JOBS 112 void 113 setjobctl(int on) 114 { 115 int i; 116 117 if (on == jobctl || rootshell == 0) 118 return; 119 if (on) { 120 if (ttyfd != -1) 121 close(ttyfd); 122 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 123 i = 0; 124 while (i <= 2 && !isatty(i)) 125 i++; 126 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 127 goto out; 128 } 129 if (ttyfd < 10) { 130 /* 131 * Keep our TTY file descriptor out of the way of 132 * the user's redirections. 133 */ 134 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 135 close(ttyfd); 136 ttyfd = -1; 137 goto out; 138 } 139 close(ttyfd); 140 ttyfd = i; 141 } 142 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 143 close(ttyfd); 144 ttyfd = -1; 145 goto out; 146 } 147 do { /* while we are in the background */ 148 initialpgrp = tcgetpgrp(ttyfd); 149 if (initialpgrp < 0) { 150 out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 151 mflag = 0; 152 return; 153 } 154 if (initialpgrp == -1) 155 initialpgrp = getpgrp(); 156 else if (initialpgrp != getpgrp()) { 157 killpg(0, SIGTTIN); 158 continue; 159 } 160 } while (0); 161 setsignal(SIGTSTP); 162 setsignal(SIGTTOU); 163 setsignal(SIGTTIN); 164 setpgid(0, rootpid); 165 tcsetpgrp(ttyfd, rootpid); 166 } else { /* turning job control off */ 167 setpgid(0, initialpgrp); 168 tcsetpgrp(ttyfd, initialpgrp); 169 close(ttyfd); 170 ttyfd = -1; 171 setsignal(SIGTSTP); 172 setsignal(SIGTTOU); 173 setsignal(SIGTTIN); 174 } 175 jobctl = on; 176 } 177 #endif 178 179 180 #ifdef mkinit 181 INCLUDE <sys/types.h> 182 INCLUDE <stdlib.h> 183 184 SHELLPROC { 185 backgndpid = -1; 186 #if JOBS 187 jobctl = 0; 188 #endif 189 } 190 191 #endif 192 193 194 195 #if JOBS 196 int 197 fgcmd(int argc __unused, char **argv) 198 { 199 struct job *jp; 200 pid_t pgrp; 201 int status; 202 203 jp = getjob(argv[1]); 204 if (jp->jobctl == 0) 205 error("job not created under job control"); 206 out1str(jp->ps[0].cmd); 207 out1c('\n'); 208 flushout(&output); 209 pgrp = jp->ps[0].pid; 210 tcsetpgrp(ttyfd, pgrp); 211 restartjob(jp); 212 jp->foreground = 1; 213 INTOFF; 214 status = waitforjob(jp, (int *)NULL); 215 INTON; 216 return status; 217 } 218 219 220 int 221 bgcmd(int argc, char **argv) 222 { 223 char s[64]; 224 struct job *jp; 225 226 do { 227 jp = getjob(*++argv); 228 if (jp->jobctl == 0) 229 error("job not created under job control"); 230 if (jp->state == JOBDONE) 231 continue; 232 restartjob(jp); 233 jp->foreground = 0; 234 fmtstr(s, 64, "[%td] ", jp - jobtab + 1); 235 out1str(s); 236 out1str(jp->ps[0].cmd); 237 out1c('\n'); 238 } while (--argc > 1); 239 return 0; 240 } 241 242 243 STATIC void 244 restartjob(struct job *jp) 245 { 246 struct procstat *ps; 247 int i; 248 249 if (jp->state == JOBDONE) 250 return; 251 setcurjob(jp); 252 INTOFF; 253 killpg(jp->ps[0].pid, SIGCONT); 254 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 255 if (WIFSTOPPED(ps->status)) { 256 ps->status = -1; 257 jp->state = 0; 258 } 259 } 260 INTON; 261 } 262 #endif 263 264 265 int 266 jobscmd(int argc, char *argv[]) 267 { 268 char *id; 269 int ch, mode; 270 271 optind = optreset = 1; 272 opterr = 0; 273 mode = SHOWJOBS_DEFAULT; 274 while ((ch = getopt(argc, argv, "lps")) != -1) { 275 switch (ch) { 276 case 'l': 277 mode = SHOWJOBS_VERBOSE; 278 break; 279 case 'p': 280 mode = SHOWJOBS_PGIDS; 281 break; 282 case 's': 283 mode = SHOWJOBS_PIDS; 284 break; 285 case '?': 286 default: 287 error("unknown option: -%c", optopt); 288 } 289 } 290 argc -= optind; 291 argv += optind; 292 293 if (argc == 0) 294 showjobs(0, mode); 295 else 296 while ((id = *argv++) != NULL) 297 showjob(getjob(id), 0, mode); 298 299 return (0); 300 } 301 302 STATIC void 303 showjob(struct job *jp, pid_t pid, int mode) 304 { 305 char s[64]; 306 struct procstat *ps; 307 struct job *j; 308 int col, curr, i, jobno, prev, procno; 309 pid_t ppid; 310 char c; 311 312 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 313 jobno = jp - jobtab + 1; 314 curr = prev = 0; 315 #if JOBS 316 if ((j = getcurjob(NULL)) != NULL) { 317 curr = j - jobtab + 1; 318 if ((j = getcurjob(j)) != NULL) 319 prev = j - jobtab + 1; 320 } 321 #endif 322 for (ps = jp->ps ; ; ps++) { /* for each process */ 323 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 324 ppid = (mode == SHOWJOBS_PIDS) ? ps->pid : 325 getpgid(ps->pid); 326 out1fmt("%d\n", (int)ppid); 327 goto skip; 328 } 329 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps && pid == 0) 330 goto skip; 331 if (pid != 0 && pid != ps->pid) 332 goto skip; 333 if (jobno == curr && ps == jp->ps) 334 c = '+'; 335 else if (jobno == prev && ps == jp->ps) 336 c = '-'; 337 else 338 c = ' '; 339 if (ps == jp->ps) 340 fmtstr(s, 64, "[%d] %c ", jobno, c); 341 else 342 fmtstr(s, 64, " %c ", c); 343 out1str(s); 344 col = strlen(s); 345 if (mode == SHOWJOBS_VERBOSE) { 346 fmtstr(s, 64, "%d ", (int)ps->pid); 347 out1str(s); 348 col += strlen(s); 349 } 350 s[0] = '\0'; 351 if (ps != jp->ps) { 352 *s = '\0'; 353 } else if (ps->status == -1) { 354 strcpy(s, "Running"); 355 } else if (WIFEXITED(ps->status)) { 356 if (WEXITSTATUS(ps->status) == 0) 357 strcpy(s, "Done"); 358 else 359 fmtstr(s, 64, "Done (%d)", 360 WEXITSTATUS(ps->status)); 361 } else { 362 #if JOBS 363 if (WIFSTOPPED(ps->status)) 364 i = WSTOPSIG(ps->status); 365 else 366 #endif 367 i = WTERMSIG(ps->status); 368 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F]) 369 scopy(sys_siglist[i & 0x7F], s); 370 else 371 fmtstr(s, 64, "Signal %d", i & 0x7F); 372 if (WCOREDUMP(ps->status)) 373 strcat(s, " (core dumped)"); 374 } 375 out1str(s); 376 col += strlen(s); 377 do { 378 out1c(' '); 379 col++; 380 } while (col < 30); 381 out1str(ps->cmd); 382 out1c('\n'); 383 skip: if (--procno <= 0) 384 break; 385 } 386 } 387 388 /* 389 * Print a list of jobs. If "change" is nonzero, only print jobs whose 390 * statuses have changed since the last call to showjobs. 391 * 392 * If the shell is interrupted in the process of creating a job, the 393 * result may be a job structure containing zero processes. Such structures 394 * will be freed here. 395 */ 396 397 void 398 showjobs(int change, int mode) 399 { 400 int jobno; 401 struct job *jp; 402 403 TRACE(("showjobs(%d) called\n", change)); 404 checkzombies(); 405 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 406 if (! jp->used) 407 continue; 408 if (jp->nprocs == 0) { 409 freejob(jp); 410 continue; 411 } 412 if (change && ! jp->changed) 413 continue; 414 showjob(jp, 0, mode); 415 jp->changed = 0; 416 if (jp->state == JOBDONE) { 417 freejob(jp); 418 } 419 } 420 } 421 422 423 /* 424 * Mark a job structure as unused. 425 */ 426 427 STATIC void 428 freejob(struct job *jp) 429 { 430 struct procstat *ps; 431 int i; 432 433 INTOFF; 434 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 435 if (ps->cmd != nullstr) 436 ckfree(ps->cmd); 437 } 438 if (jp->ps != &jp->ps0) 439 ckfree(jp->ps); 440 jp->used = 0; 441 #if JOBS 442 deljob(jp); 443 #endif 444 INTON; 445 } 446 447 448 449 int 450 waitcmd(int argc, char **argv) 451 { 452 struct job *job; 453 int status, retval; 454 struct job *jp; 455 456 if (argc > 1) { 457 job = getjob(argv[1]); 458 } else { 459 job = NULL; 460 } 461 462 /* 463 * Loop until a process is terminated or stopped, or a SIGINT is 464 * received. 465 */ 466 467 in_waitcmd++; 468 do { 469 if (job != NULL) { 470 if (job->state) { 471 status = job->ps[job->nprocs - 1].status; 472 if (WIFEXITED(status)) 473 retval = WEXITSTATUS(status); 474 #if JOBS 475 else if (WIFSTOPPED(status)) 476 retval = WSTOPSIG(status) + 128; 477 #endif 478 else 479 retval = WTERMSIG(status) + 128; 480 if (! iflag) 481 freejob(job); 482 in_waitcmd--; 483 return retval; 484 } 485 } else { 486 for (jp = jobtab ; ; jp++) { 487 if (jp >= jobtab + njobs) { /* no running procs */ 488 in_waitcmd--; 489 return 0; 490 } 491 if (jp->used && jp->state == 0) 492 break; 493 } 494 } 495 } while (dowait(1, (struct job *)NULL) != -1); 496 in_waitcmd--; 497 498 return 0; 499 } 500 501 502 503 int 504 jobidcmd(int argc __unused, char **argv) 505 { 506 struct job *jp; 507 int i; 508 509 jp = getjob(argv[1]); 510 for (i = 0 ; i < jp->nprocs ; ) { 511 out1fmt("%d", (int)jp->ps[i].pid); 512 out1c(++i < jp->nprocs? ' ' : '\n'); 513 } 514 return 0; 515 } 516 517 518 519 /* 520 * Convert a job name to a job structure. 521 */ 522 523 STATIC struct job * 524 getjob(char *name) 525 { 526 int jobno; 527 struct job *found, *jp; 528 pid_t pid; 529 int i; 530 531 if (name == NULL) { 532 #if JOBS 533 currentjob: if ((jp = getcurjob(NULL)) == NULL) 534 error("No current job"); 535 return (jp); 536 #else 537 error("No current job"); 538 #endif 539 } else if (name[0] == '%') { 540 if (is_digit(name[1])) { 541 jobno = number(name + 1); 542 if (jobno > 0 && jobno <= njobs 543 && jobtab[jobno - 1].used != 0) 544 return &jobtab[jobno - 1]; 545 #if JOBS 546 } else if (name[1] == '%' && name[2] == '\0') { 547 goto currentjob; 548 } else if (name[1] == '+' && name[2] == '\0') { 549 goto currentjob; 550 } else if (name[1] == '-' && name[2] == '\0') { 551 if ((jp = getcurjob(NULL)) == NULL || 552 (jp = getcurjob(jp)) == NULL) 553 error("No previous job"); 554 return (jp); 555 #endif 556 } else if (name[1] == '?') { 557 found = NULL; 558 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 559 if (jp->used && jp->nprocs > 0 560 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 561 if (found) 562 error("%s: ambiguous", name); 563 found = jp; 564 } 565 } 566 if (found != NULL) 567 return (found); 568 } else { 569 found = NULL; 570 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 571 if (jp->used && jp->nprocs > 0 572 && prefix(name + 1, jp->ps[0].cmd)) { 573 if (found) 574 error("%s: ambiguous", name); 575 found = jp; 576 } 577 } 578 if (found) 579 return found; 580 } 581 } else if (is_number(name)) { 582 pid = (pid_t)number(name); 583 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 584 if (jp->used && jp->nprocs > 0 585 && jp->ps[jp->nprocs - 1].pid == pid) 586 return jp; 587 } 588 } 589 error("No such job: %s", name); 590 /*NOTREACHED*/ 591 return NULL; 592 } 593 594 595 596 /* 597 * Return a new job structure, 598 */ 599 600 struct job * 601 makejob(union node *node __unused, int nprocs) 602 { 603 int i; 604 struct job *jp; 605 606 for (i = njobs, jp = jobtab ; ; jp++) { 607 if (--i < 0) { 608 INTOFF; 609 if (njobs == 0) { 610 jobtab = ckmalloc(4 * sizeof jobtab[0]); 611 #if JOBS 612 jobmru = NULL; 613 #endif 614 } else { 615 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 616 memcpy(jp, jobtab, njobs * sizeof jp[0]); 617 #if JOBS 618 /* Relocate `next' pointers and list head */ 619 if (jobmru != NULL) 620 jobmru = &jp[jobmru - jobtab]; 621 for (i = 0; i < njobs; i++) 622 if (jp[i].next != NULL) 623 jp[i].next = &jp[jp[i].next - 624 jobtab]; 625 #endif 626 /* Relocate `ps' pointers */ 627 for (i = 0; i < njobs; i++) 628 if (jp[i].ps == &jobtab[i].ps0) 629 jp[i].ps = &jp[i].ps0; 630 ckfree(jobtab); 631 jobtab = jp; 632 } 633 jp = jobtab + njobs; 634 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 635 INTON; 636 break; 637 } 638 if (jp->used == 0) 639 break; 640 } 641 INTOFF; 642 jp->state = 0; 643 jp->used = 1; 644 jp->changed = 0; 645 jp->nprocs = 0; 646 jp->foreground = 0; 647 #if JOBS 648 jp->jobctl = jobctl; 649 jp->next = NULL; 650 #endif 651 if (nprocs > 1) { 652 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 653 } else { 654 jp->ps = &jp->ps0; 655 } 656 INTON; 657 TRACE(("makejob(%p, %d) returns %%%d\n", (void *)node, nprocs, 658 jp - jobtab + 1)); 659 return jp; 660 } 661 662 #if JOBS 663 STATIC void 664 setcurjob(struct job *cj) 665 { 666 struct job *jp, *prev; 667 668 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 669 if (jp == cj) { 670 if (prev != NULL) 671 prev->next = jp->next; 672 else 673 jobmru = jp->next; 674 jp->next = jobmru; 675 jobmru = cj; 676 return; 677 } 678 } 679 cj->next = jobmru; 680 jobmru = cj; 681 } 682 683 STATIC void 684 deljob(struct job *j) 685 { 686 struct job *jp, *prev; 687 688 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 689 if (jp == j) { 690 if (prev != NULL) 691 prev->next = jp->next; 692 else 693 jobmru = jp->next; 694 return; 695 } 696 } 697 } 698 699 /* 700 * Return the most recently used job that isn't `nj', and preferably one 701 * that is stopped. 702 */ 703 STATIC struct job * 704 getcurjob(struct job *nj) 705 { 706 struct job *jp; 707 708 /* Try to find a stopped one.. */ 709 for (jp = jobmru; jp != NULL; jp = jp->next) 710 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 711 return (jp); 712 /* Otherwise the most recently used job that isn't `nj' */ 713 for (jp = jobmru; jp != NULL; jp = jp->next) 714 if (jp->used && jp != nj) 715 return (jp); 716 717 return (NULL); 718 } 719 720 #endif 721 722 /* 723 * Fork of a subshell. If we are doing job control, give the subshell its 724 * own process group. Jp is a job structure that the job is to be added to. 725 * N is the command that will be evaluated by the child. Both jp and n may 726 * be NULL. The mode parameter can be one of the following: 727 * FORK_FG - Fork off a foreground process. 728 * FORK_BG - Fork off a background process. 729 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 730 * process group even if job control is on. 731 * 732 * When job control is turned off, background processes have their standard 733 * input redirected to /dev/null (except for the second and later processes 734 * in a pipeline). 735 */ 736 737 pid_t 738 forkshell(struct job *jp, union node *n, int mode) 739 { 740 pid_t pid; 741 pid_t pgrp; 742 743 TRACE(("forkshell(%%%d, %p, %d) called\n", jp - jobtab, (void *)n, 744 mode)); 745 INTOFF; 746 if (mode == FORK_BG) 747 checkzombies(); 748 flushall(); 749 pid = fork(); 750 if (pid == -1) { 751 TRACE(("Fork failed, errno=%d\n", errno)); 752 INTON; 753 error("Cannot fork: %s", strerror(errno)); 754 } 755 if (pid == 0) { 756 struct job *p; 757 int wasroot; 758 int i; 759 760 TRACE(("Child shell %d\n", (int)getpid())); 761 wasroot = rootshell; 762 rootshell = 0; 763 handler = &main_handler; 764 closescript(); 765 INTON; 766 clear_traps(); 767 #if JOBS 768 jobctl = 0; /* do job control only in root shell */ 769 if (wasroot && mode != FORK_NOJOB && mflag) { 770 if (jp == NULL || jp->nprocs == 0) 771 pgrp = getpid(); 772 else 773 pgrp = jp->ps[0].pid; 774 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 775 /*** this causes superfluous TIOCSPGRPS ***/ 776 if (tcsetpgrp(ttyfd, pgrp) < 0) 777 error("tcsetpgrp failed, errno=%d", errno); 778 } 779 setsignal(SIGTSTP); 780 setsignal(SIGTTOU); 781 } else if (mode == FORK_BG) { 782 ignoresig(SIGINT); 783 ignoresig(SIGQUIT); 784 if ((jp == NULL || jp->nprocs == 0) && 785 ! fd0_redirected_p ()) { 786 close(0); 787 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 788 error("Can't open %s: %s", 789 _PATH_DEVNULL, strerror(errno)); 790 } 791 } 792 #else 793 if (mode == FORK_BG) { 794 ignoresig(SIGINT); 795 ignoresig(SIGQUIT); 796 if ((jp == NULL || jp->nprocs == 0) && 797 ! fd0_redirected_p ()) { 798 close(0); 799 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 800 error("Can't open %s: %s", 801 _PATH_DEVNULL, strerror(errno)); 802 } 803 } 804 #endif 805 INTOFF; 806 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 807 if (p->used) 808 freejob(p); 809 INTON; 810 if (wasroot && iflag) { 811 setsignal(SIGINT); 812 setsignal(SIGQUIT); 813 setsignal(SIGTERM); 814 } 815 return pid; 816 } 817 if (rootshell && mode != FORK_NOJOB && mflag) { 818 if (jp == NULL || jp->nprocs == 0) 819 pgrp = pid; 820 else 821 pgrp = jp->ps[0].pid; 822 setpgid(pid, pgrp); 823 } 824 if (mode == FORK_BG) 825 backgndpid = pid; /* set $! */ 826 if (jp) { 827 struct procstat *ps = &jp->ps[jp->nprocs++]; 828 ps->pid = pid; 829 ps->status = -1; 830 ps->cmd = nullstr; 831 if (iflag && rootshell && n) 832 ps->cmd = commandtext(n); 833 jp->foreground = mode == FORK_FG; 834 #if JOBS 835 setcurjob(jp); 836 #endif 837 } 838 INTON; 839 TRACE(("In parent shell: child = %d\n", (int)pid)); 840 return pid; 841 } 842 843 844 845 /* 846 * Wait for job to finish. 847 * 848 * Under job control we have the problem that while a child process is 849 * running interrupts generated by the user are sent to the child but not 850 * to the shell. This means that an infinite loop started by an inter- 851 * active user may be hard to kill. With job control turned off, an 852 * interactive user may place an interactive program inside a loop. If 853 * the interactive program catches interrupts, the user doesn't want 854 * these interrupts to also abort the loop. The approach we take here 855 * is to have the shell ignore interrupt signals while waiting for a 856 * foreground process to terminate, and then send itself an interrupt 857 * signal if the child process was terminated by an interrupt signal. 858 * Unfortunately, some programs want to do a bit of cleanup and then 859 * exit on interrupt; unless these processes terminate themselves by 860 * sending a signal to themselves (instead of calling exit) they will 861 * confuse this approach. 862 */ 863 864 int 865 waitforjob(struct job *jp, int *origstatus) 866 { 867 #if JOBS 868 pid_t mypgrp = getpgrp(); 869 #endif 870 int status; 871 int st; 872 873 INTOFF; 874 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 875 while (jp->state == 0) 876 if (dowait(1, jp) == -1) 877 dotrap(); 878 #if JOBS 879 if (jp->jobctl) { 880 if (tcsetpgrp(ttyfd, mypgrp) < 0) 881 error("tcsetpgrp failed, errno=%d\n", errno); 882 } 883 if (jp->state == JOBSTOPPED) 884 setcurjob(jp); 885 #endif 886 status = jp->ps[jp->nprocs - 1].status; 887 if (origstatus != NULL) 888 *origstatus = status; 889 /* convert to 8 bits */ 890 if (WIFEXITED(status)) 891 st = WEXITSTATUS(status); 892 #if JOBS 893 else if (WIFSTOPPED(status)) 894 st = WSTOPSIG(status) + 128; 895 #endif 896 else 897 st = WTERMSIG(status) + 128; 898 if (! JOBS || jp->state == JOBDONE) 899 freejob(jp); 900 if (int_pending()) { 901 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 902 kill(getpid(), SIGINT); 903 else 904 CLEAR_PENDING_INT; 905 } 906 INTON; 907 return st; 908 } 909 910 911 912 /* 913 * Wait for a process to terminate. 914 */ 915 916 STATIC pid_t 917 dowait(int block, struct job *job) 918 { 919 pid_t pid; 920 int status; 921 struct procstat *sp; 922 struct job *jp; 923 struct job *thisjob; 924 int done; 925 int stopped; 926 int sig; 927 int i; 928 929 in_dowait++; 930 TRACE(("dowait(%d) called\n", block)); 931 do { 932 pid = waitproc(block, &status); 933 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 934 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 935 (pid > 0 && WIFSTOPPED(status) && !iflag)); 936 in_dowait--; 937 if (pid == -1 && errno == ECHILD && job != NULL) 938 job->state = JOBDONE; 939 if (breakwaitcmd != 0) { 940 breakwaitcmd = 0; 941 if (pid <= 0) 942 return -1; 943 } 944 if (pid <= 0) 945 return pid; 946 INTOFF; 947 thisjob = NULL; 948 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 949 if (jp->used) { 950 done = 1; 951 stopped = 1; 952 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 953 if (sp->pid == -1) 954 continue; 955 if (sp->pid == pid) { 956 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 957 (int)pid, sp->status, 958 status)); 959 sp->status = status; 960 thisjob = jp; 961 } 962 if (sp->status == -1) 963 stopped = 0; 964 else if (WIFSTOPPED(sp->status)) 965 done = 0; 966 } 967 if (stopped) { /* stopped or done */ 968 int state = done? JOBDONE : JOBSTOPPED; 969 if (jp->state != state) { 970 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 971 jp->state = state; 972 #if JOBS 973 if (done) 974 deljob(jp); 975 #endif 976 } 977 } 978 } 979 } 980 INTON; 981 if (! rootshell || ! iflag || (job && thisjob == job)) { 982 #if JOBS 983 if (WIFSTOPPED(status)) 984 sig = WSTOPSIG(status); 985 else 986 #endif 987 { 988 if (WIFEXITED(status)) 989 sig = 0; 990 else 991 sig = WTERMSIG(status); 992 } 993 if (sig != 0 && sig != SIGINT && sig != SIGPIPE) { 994 if (!mflag || 995 (thisjob->foreground && !WIFSTOPPED(status))) { 996 i = WTERMSIG(status); 997 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F]) 998 out1str(sys_siglist[i & 0x7F]); 999 else 1000 out1fmt("Signal %d", i & 0x7F); 1001 if (WCOREDUMP(status)) 1002 out1str(" (core dumped)"); 1003 out1c('\n'); 1004 } else 1005 showjob(thisjob, pid, SHOWJOBS_DEFAULT); 1006 } 1007 } else { 1008 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1009 if (thisjob) 1010 thisjob->changed = 1; 1011 } 1012 return pid; 1013 } 1014 1015 1016 1017 /* 1018 * Do a wait system call. If job control is compiled in, we accept 1019 * stopped processes. If block is zero, we return a value of zero 1020 * rather than blocking. 1021 */ 1022 STATIC pid_t 1023 waitproc(int block, int *status) 1024 { 1025 int flags; 1026 1027 #if JOBS 1028 flags = WUNTRACED; 1029 #else 1030 flags = 0; 1031 #endif 1032 if (block == 0) 1033 flags |= WNOHANG; 1034 return wait3(status, flags, (struct rusage *)NULL); 1035 } 1036 1037 /* 1038 * return 1 if there are stopped jobs, otherwise 0 1039 */ 1040 int job_warning = 0; 1041 int 1042 stoppedjobs(void) 1043 { 1044 int jobno; 1045 struct job *jp; 1046 1047 if (job_warning) 1048 return (0); 1049 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1050 if (jp->used == 0) 1051 continue; 1052 if (jp->state == JOBSTOPPED) { 1053 out2fmt_flush("You have stopped jobs.\n"); 1054 job_warning = 2; 1055 return (1); 1056 } 1057 } 1058 1059 return (0); 1060 } 1061 1062 1063 STATIC void 1064 checkzombies(void) 1065 { 1066 while (njobs > 0 && dowait(0, NULL) > 0) 1067 ; 1068 } 1069 1070 1071 /* 1072 * Return a string identifying a command (to be printed by the 1073 * jobs command. 1074 */ 1075 1076 STATIC char *cmdnextc; 1077 STATIC int cmdnleft; 1078 #define MAXCMDTEXT 200 1079 1080 char * 1081 commandtext(union node *n) 1082 { 1083 char *name; 1084 1085 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1086 cmdnleft = MAXCMDTEXT - 4; 1087 cmdtxt(n); 1088 *cmdnextc = '\0'; 1089 return name; 1090 } 1091 1092 1093 STATIC void 1094 cmdtxt(union node *n) 1095 { 1096 union node *np; 1097 struct nodelist *lp; 1098 const char *p; 1099 int i; 1100 char s[2]; 1101 1102 if (n == NULL) 1103 return; 1104 switch (n->type) { 1105 case NSEMI: 1106 cmdtxt(n->nbinary.ch1); 1107 cmdputs("; "); 1108 cmdtxt(n->nbinary.ch2); 1109 break; 1110 case NAND: 1111 cmdtxt(n->nbinary.ch1); 1112 cmdputs(" && "); 1113 cmdtxt(n->nbinary.ch2); 1114 break; 1115 case NOR: 1116 cmdtxt(n->nbinary.ch1); 1117 cmdputs(" || "); 1118 cmdtxt(n->nbinary.ch2); 1119 break; 1120 case NPIPE: 1121 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1122 cmdtxt(lp->n); 1123 if (lp->next) 1124 cmdputs(" | "); 1125 } 1126 break; 1127 case NSUBSHELL: 1128 cmdputs("("); 1129 cmdtxt(n->nredir.n); 1130 cmdputs(")"); 1131 break; 1132 case NREDIR: 1133 case NBACKGND: 1134 cmdtxt(n->nredir.n); 1135 break; 1136 case NIF: 1137 cmdputs("if "); 1138 cmdtxt(n->nif.test); 1139 cmdputs("; then "); 1140 cmdtxt(n->nif.ifpart); 1141 cmdputs("..."); 1142 break; 1143 case NWHILE: 1144 cmdputs("while "); 1145 goto until; 1146 case NUNTIL: 1147 cmdputs("until "); 1148 until: 1149 cmdtxt(n->nbinary.ch1); 1150 cmdputs("; do "); 1151 cmdtxt(n->nbinary.ch2); 1152 cmdputs("; done"); 1153 break; 1154 case NFOR: 1155 cmdputs("for "); 1156 cmdputs(n->nfor.var); 1157 cmdputs(" in ..."); 1158 break; 1159 case NCASE: 1160 cmdputs("case "); 1161 cmdputs(n->ncase.expr->narg.text); 1162 cmdputs(" in ..."); 1163 break; 1164 case NDEFUN: 1165 cmdputs(n->narg.text); 1166 cmdputs("() ..."); 1167 break; 1168 case NCMD: 1169 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1170 cmdtxt(np); 1171 if (np->narg.next) 1172 cmdputs(" "); 1173 } 1174 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1175 cmdputs(" "); 1176 cmdtxt(np); 1177 } 1178 break; 1179 case NARG: 1180 cmdputs(n->narg.text); 1181 break; 1182 case NTO: 1183 p = ">"; i = 1; goto redir; 1184 case NAPPEND: 1185 p = ">>"; i = 1; goto redir; 1186 case NTOFD: 1187 p = ">&"; i = 1; goto redir; 1188 case NCLOBBER: 1189 p = ">|"; i = 1; goto redir; 1190 case NFROM: 1191 p = "<"; i = 0; goto redir; 1192 case NFROMTO: 1193 p = "<>"; i = 0; goto redir; 1194 case NFROMFD: 1195 p = "<&"; i = 0; goto redir; 1196 redir: 1197 if (n->nfile.fd != i) { 1198 s[0] = n->nfile.fd + '0'; 1199 s[1] = '\0'; 1200 cmdputs(s); 1201 } 1202 cmdputs(p); 1203 if (n->type == NTOFD || n->type == NFROMFD) { 1204 if (n->ndup.dupfd >= 0) 1205 s[0] = n->ndup.dupfd + '0'; 1206 else 1207 s[0] = '-'; 1208 s[1] = '\0'; 1209 cmdputs(s); 1210 } else { 1211 cmdtxt(n->nfile.fname); 1212 } 1213 break; 1214 case NHERE: 1215 case NXHERE: 1216 cmdputs("<<..."); 1217 break; 1218 default: 1219 cmdputs("???"); 1220 break; 1221 } 1222 } 1223 1224 1225 1226 STATIC void 1227 cmdputs(const char *s) 1228 { 1229 const char *p; 1230 char *q; 1231 char c; 1232 int subtype = 0; 1233 1234 if (cmdnleft <= 0) 1235 return; 1236 p = s; 1237 q = cmdnextc; 1238 while ((c = *p++) != '\0') { 1239 if (c == CTLESC) 1240 *q++ = *p++; 1241 else if (c == CTLVAR) { 1242 *q++ = '$'; 1243 if (--cmdnleft > 0) 1244 *q++ = '{'; 1245 subtype = *p++; 1246 } else if (c == '=' && subtype != 0) { 1247 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL]; 1248 subtype = 0; 1249 } else if (c == CTLENDVAR) { 1250 *q++ = '}'; 1251 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) 1252 cmdnleft++; /* ignore it */ 1253 else 1254 *q++ = c; 1255 if (--cmdnleft <= 0) { 1256 *q++ = '.'; 1257 *q++ = '.'; 1258 *q++ = '.'; 1259 break; 1260 } 1261 } 1262 cmdnextc = q; 1263 } 1264