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 <sys/ioctl.h> 42 #include <sys/param.h> 43 #include <sys/resource.h> 44 #include <sys/time.h> 45 #include <sys/wait.h> 46 #include <errno.h> 47 #include <fcntl.h> 48 #include <paths.h> 49 #include <signal.h> 50 #include <stddef.h> 51 #include <stdlib.h> 52 #include <unistd.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 MKINIT struct job *bgjob = NULL; /* last background process */ 79 #if JOBS 80 static struct job *jobmru; /* most recently used job list */ 81 static pid_t initialpgrp; /* pgrp of shell on invocation */ 82 #endif 83 int in_waitcmd = 0; /* are we in waitcmd()? */ 84 int in_dowait = 0; /* are we in dowait()? */ 85 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 86 static int ttyfd = -1; 87 88 #if JOBS 89 static void restartjob(struct job *); 90 #endif 91 static void freejob(struct job *); 92 static struct job *getjob(char *); 93 static pid_t dowait(int, struct job *); 94 static pid_t waitproc(int, int *); 95 static void checkzombies(void); 96 static void cmdtxt(union node *); 97 static void cmdputs(const char *); 98 #if JOBS 99 static void setcurjob(struct job *); 100 static void deljob(struct job *); 101 static struct job *getcurjob(struct job *); 102 #endif 103 static void printjobcmd(struct job *); 104 static void showjob(struct job *, int); 105 106 107 /* 108 * Turn job control on and off. 109 */ 110 111 MKINIT int jobctl; 112 113 #if JOBS 114 void 115 setjobctl(int on) 116 { 117 int i; 118 119 if (on == jobctl || rootshell == 0) 120 return; 121 if (on) { 122 if (ttyfd != -1) 123 close(ttyfd); 124 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 125 i = 0; 126 while (i <= 2 && !isatty(i)) 127 i++; 128 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 129 goto out; 130 } 131 if (ttyfd < 10) { 132 /* 133 * Keep our TTY file descriptor out of the way of 134 * the user's redirections. 135 */ 136 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 137 close(ttyfd); 138 ttyfd = -1; 139 goto out; 140 } 141 close(ttyfd); 142 ttyfd = i; 143 } 144 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 145 close(ttyfd); 146 ttyfd = -1; 147 goto out; 148 } 149 do { /* while we are in the background */ 150 initialpgrp = tcgetpgrp(ttyfd); 151 if (initialpgrp < 0) { 152 out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 153 mflag = 0; 154 return; 155 } 156 if (initialpgrp != getpgrp()) { 157 kill(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 #if JOBS 181 int 182 fgcmd(int argc __unused, char **argv) 183 { 184 struct job *jp; 185 pid_t pgrp; 186 int status; 187 188 jp = getjob(argv[1]); 189 if (jp->jobctl == 0) 190 error("job not created under job control"); 191 printjobcmd(jp); 192 flushout(&output); 193 pgrp = jp->ps[0].pid; 194 tcsetpgrp(ttyfd, pgrp); 195 restartjob(jp); 196 jp->foreground = 1; 197 INTOFF; 198 status = waitforjob(jp, (int *)NULL); 199 INTON; 200 return status; 201 } 202 203 204 int 205 bgcmd(int argc, char **argv) 206 { 207 struct job *jp; 208 209 do { 210 jp = getjob(*++argv); 211 if (jp->jobctl == 0) 212 error("job not created under job control"); 213 if (jp->state == JOBDONE) 214 continue; 215 restartjob(jp); 216 jp->foreground = 0; 217 out1fmt("[%td] ", jp - jobtab + 1); 218 printjobcmd(jp); 219 } while (--argc > 1); 220 return 0; 221 } 222 223 224 static void 225 restartjob(struct job *jp) 226 { 227 struct procstat *ps; 228 int i; 229 230 if (jp->state == JOBDONE) 231 return; 232 setcurjob(jp); 233 INTOFF; 234 kill(-jp->ps[0].pid, SIGCONT); 235 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 236 if (WIFSTOPPED(ps->status)) { 237 ps->status = -1; 238 jp->state = 0; 239 } 240 } 241 INTON; 242 } 243 #endif 244 245 246 int 247 jobscmd(int argc, char *argv[]) 248 { 249 char *id; 250 int ch, mode; 251 252 optind = optreset = 1; 253 opterr = 0; 254 mode = SHOWJOBS_DEFAULT; 255 while ((ch = getopt(argc, argv, "lps")) != -1) { 256 switch (ch) { 257 case 'l': 258 mode = SHOWJOBS_VERBOSE; 259 break; 260 case 'p': 261 mode = SHOWJOBS_PGIDS; 262 break; 263 case 's': 264 mode = SHOWJOBS_PIDS; 265 break; 266 case '?': 267 default: 268 error("unknown option: -%c", optopt); 269 } 270 } 271 argc -= optind; 272 argv += optind; 273 274 if (argc == 0) 275 showjobs(0, mode); 276 else 277 while ((id = *argv++) != NULL) 278 showjob(getjob(id), mode); 279 280 return (0); 281 } 282 283 static void 284 printjobcmd(struct job *jp) 285 { 286 struct procstat *ps; 287 int i; 288 289 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 290 out1str(ps->cmd); 291 if (i > 0) 292 out1str(" | "); 293 } 294 out1c('\n'); 295 } 296 297 static void 298 showjob(struct job *jp, int mode) 299 { 300 char s[64]; 301 char statestr[64]; 302 struct procstat *ps; 303 struct job *j; 304 int col, curr, i, jobno, prev, procno; 305 char c; 306 307 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 308 jobno = jp - jobtab + 1; 309 curr = prev = 0; 310 #if JOBS 311 if ((j = getcurjob(NULL)) != NULL) { 312 curr = j - jobtab + 1; 313 if ((j = getcurjob(j)) != NULL) 314 prev = j - jobtab + 1; 315 } 316 #endif 317 ps = jp->ps + jp->nprocs - 1; 318 if (jp->state == 0) { 319 strcpy(statestr, "Running"); 320 #if JOBS 321 } else if (jp->state == JOBSTOPPED) { 322 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 323 ps--; 324 if (WIFSTOPPED(ps->status)) 325 i = WSTOPSIG(ps->status); 326 else 327 i = -1; 328 if (i > 0 && i < sys_nsig && sys_siglist[i]) 329 strcpy(statestr, sys_siglist[i]); 330 else 331 strcpy(statestr, "Suspended"); 332 #endif 333 } else if (WIFEXITED(ps->status)) { 334 if (WEXITSTATUS(ps->status) == 0) 335 strcpy(statestr, "Done"); 336 else 337 fmtstr(statestr, 64, "Done(%d)", 338 WEXITSTATUS(ps->status)); 339 } else { 340 i = WTERMSIG(ps->status); 341 if (i > 0 && i < sys_nsig && sys_siglist[i]) 342 strcpy(statestr, sys_siglist[i]); 343 else 344 fmtstr(statestr, 64, "Signal %d", i); 345 if (WCOREDUMP(ps->status)) 346 strcat(statestr, " (core dumped)"); 347 } 348 349 for (ps = jp->ps ; ; ps++) { /* for each process */ 350 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 351 out1fmt("%d\n", (int)ps->pid); 352 goto skip; 353 } 354 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 355 goto skip; 356 if (jobno == curr && ps == jp->ps) 357 c = '+'; 358 else if (jobno == prev && ps == jp->ps) 359 c = '-'; 360 else 361 c = ' '; 362 if (ps == jp->ps) 363 fmtstr(s, 64, "[%d] %c ", jobno, c); 364 else 365 fmtstr(s, 64, " %c ", c); 366 out1str(s); 367 col = strlen(s); 368 if (mode == SHOWJOBS_VERBOSE) { 369 fmtstr(s, 64, "%d ", (int)ps->pid); 370 out1str(s); 371 col += strlen(s); 372 } 373 if (ps == jp->ps) { 374 out1str(statestr); 375 col += strlen(statestr); 376 } 377 do { 378 out1c(' '); 379 col++; 380 } while (col < 30); 381 if (mode == SHOWJOBS_VERBOSE) { 382 out1str(ps->cmd); 383 out1c('\n'); 384 } else 385 printjobcmd(jp); 386 skip: if (--procno <= 0) 387 break; 388 } 389 } 390 391 /* 392 * Print a list of jobs. If "change" is nonzero, only print jobs whose 393 * statuses have changed since the last call to showjobs. 394 * 395 * If the shell is interrupted in the process of creating a job, the 396 * result may be a job structure containing zero processes. Such structures 397 * will be freed here. 398 */ 399 400 void 401 showjobs(int change, int mode) 402 { 403 int jobno; 404 struct job *jp; 405 406 TRACE(("showjobs(%d) called\n", change)); 407 checkzombies(); 408 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 409 if (! jp->used) 410 continue; 411 if (jp->nprocs == 0) { 412 freejob(jp); 413 continue; 414 } 415 if (change && ! jp->changed) 416 continue; 417 showjob(jp, mode); 418 jp->changed = 0; 419 /* Hack: discard jobs for which $! has not been referenced 420 * in interactive mode when they terminate. 421 */ 422 if (jp->state == JOBDONE && !jp->remembered && 423 (iflag || jp != bgjob)) { 424 freejob(jp); 425 } 426 } 427 } 428 429 430 /* 431 * Mark a job structure as unused. 432 */ 433 434 static void 435 freejob(struct job *jp) 436 { 437 struct procstat *ps; 438 int i; 439 440 INTOFF; 441 if (bgjob == jp) 442 bgjob = NULL; 443 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 444 if (ps->cmd != nullstr) 445 ckfree(ps->cmd); 446 } 447 if (jp->ps != &jp->ps0) 448 ckfree(jp->ps); 449 jp->used = 0; 450 #if JOBS 451 deljob(jp); 452 #endif 453 INTON; 454 } 455 456 457 458 int 459 waitcmd(int argc, char **argv) 460 { 461 struct job *job; 462 int status, retval; 463 struct job *jp; 464 465 if (argc > 1) { 466 job = getjob(argv[1]); 467 } else { 468 job = NULL; 469 } 470 471 /* 472 * Loop until a process is terminated or stopped, or a SIGINT is 473 * received. 474 */ 475 476 in_waitcmd++; 477 do { 478 if (job != NULL) { 479 if (job->state) { 480 status = job->ps[job->nprocs - 1].status; 481 if (WIFEXITED(status)) 482 retval = WEXITSTATUS(status); 483 #if JOBS 484 else if (WIFSTOPPED(status)) 485 retval = WSTOPSIG(status) + 128; 486 #endif 487 else 488 retval = WTERMSIG(status) + 128; 489 if (! iflag || ! job->changed) 490 freejob(job); 491 else { 492 job->remembered = 0; 493 if (job == bgjob) 494 bgjob = NULL; 495 } 496 in_waitcmd--; 497 return retval; 498 } 499 } else { 500 for (jp = jobtab ; jp < jobtab + njobs; jp++) 501 if (jp->used && jp->state == JOBDONE) { 502 if (! iflag || ! jp->changed) 503 freejob(jp); 504 else { 505 jp->remembered = 0; 506 if (jp == bgjob) 507 bgjob = NULL; 508 } 509 } 510 for (jp = jobtab ; ; jp++) { 511 if (jp >= jobtab + njobs) { /* no running procs */ 512 in_waitcmd--; 513 return 0; 514 } 515 if (jp->used && jp->state == 0) 516 break; 517 } 518 } 519 } while (dowait(1, (struct job *)NULL) != -1); 520 in_waitcmd--; 521 522 return 0; 523 } 524 525 526 527 int 528 jobidcmd(int argc __unused, char **argv) 529 { 530 struct job *jp; 531 int i; 532 533 jp = getjob(argv[1]); 534 for (i = 0 ; i < jp->nprocs ; ) { 535 out1fmt("%d", (int)jp->ps[i].pid); 536 out1c(++i < jp->nprocs? ' ' : '\n'); 537 } 538 return 0; 539 } 540 541 542 543 /* 544 * Convert a job name to a job structure. 545 */ 546 547 static struct job * 548 getjob(char *name) 549 { 550 int jobno; 551 struct job *found, *jp; 552 pid_t pid; 553 int i; 554 555 if (name == NULL) { 556 #if JOBS 557 currentjob: if ((jp = getcurjob(NULL)) == NULL) 558 error("No current job"); 559 return (jp); 560 #else 561 error("No current job"); 562 #endif 563 } else if (name[0] == '%') { 564 if (is_digit(name[1])) { 565 jobno = number(name + 1); 566 if (jobno > 0 && jobno <= njobs 567 && jobtab[jobno - 1].used != 0) 568 return &jobtab[jobno - 1]; 569 #if JOBS 570 } else if (name[1] == '%' && name[2] == '\0') { 571 goto currentjob; 572 } else if (name[1] == '+' && name[2] == '\0') { 573 goto currentjob; 574 } else if (name[1] == '-' && name[2] == '\0') { 575 if ((jp = getcurjob(NULL)) == NULL || 576 (jp = getcurjob(jp)) == NULL) 577 error("No previous job"); 578 return (jp); 579 #endif 580 } else if (name[1] == '?') { 581 found = NULL; 582 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 583 if (jp->used && jp->nprocs > 0 584 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 585 if (found) 586 error("%s: ambiguous", name); 587 found = jp; 588 } 589 } 590 if (found != NULL) 591 return (found); 592 } else { 593 found = NULL; 594 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 595 if (jp->used && jp->nprocs > 0 596 && prefix(name + 1, jp->ps[0].cmd)) { 597 if (found) 598 error("%s: ambiguous", name); 599 found = jp; 600 } 601 } 602 if (found) 603 return found; 604 } 605 } else if (is_number(name)) { 606 pid = (pid_t)number(name); 607 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 608 if (jp->used && jp->nprocs > 0 609 && jp->ps[jp->nprocs - 1].pid == pid) 610 return jp; 611 } 612 } 613 error("No such job: %s", name); 614 /*NOTREACHED*/ 615 return NULL; 616 } 617 618 619 pid_t 620 getjobpgrp(char *name) 621 { 622 struct job *jp; 623 624 jp = getjob(name); 625 return -jp->ps[0].pid; 626 } 627 628 /* 629 * Return a new job structure, 630 */ 631 632 struct job * 633 makejob(union node *node __unused, int nprocs) 634 { 635 int i; 636 struct job *jp; 637 638 for (i = njobs, jp = jobtab ; ; jp++) { 639 if (--i < 0) { 640 INTOFF; 641 if (njobs == 0) { 642 jobtab = ckmalloc(4 * sizeof jobtab[0]); 643 #if JOBS 644 jobmru = NULL; 645 #endif 646 } else { 647 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 648 memcpy(jp, jobtab, njobs * sizeof jp[0]); 649 #if JOBS 650 /* Relocate `next' pointers and list head */ 651 if (jobmru != NULL) 652 jobmru = &jp[jobmru - jobtab]; 653 for (i = 0; i < njobs; i++) 654 if (jp[i].next != NULL) 655 jp[i].next = &jp[jp[i].next - 656 jobtab]; 657 #endif 658 if (bgjob != NULL) 659 bgjob = &jp[bgjob - jobtab]; 660 /* Relocate `ps' pointers */ 661 for (i = 0; i < njobs; i++) 662 if (jp[i].ps == &jobtab[i].ps0) 663 jp[i].ps = &jp[i].ps0; 664 ckfree(jobtab); 665 jobtab = jp; 666 } 667 jp = jobtab + njobs; 668 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 669 INTON; 670 break; 671 } 672 if (jp->used == 0) 673 break; 674 } 675 INTOFF; 676 jp->state = 0; 677 jp->used = 1; 678 jp->changed = 0; 679 jp->nprocs = 0; 680 jp->foreground = 0; 681 jp->remembered = 0; 682 #if JOBS 683 jp->jobctl = jobctl; 684 jp->next = NULL; 685 #endif 686 if (nprocs > 1) { 687 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 688 } else { 689 jp->ps = &jp->ps0; 690 } 691 INTON; 692 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 693 jp - jobtab + 1)); 694 return jp; 695 } 696 697 #if JOBS 698 static void 699 setcurjob(struct job *cj) 700 { 701 struct job *jp, *prev; 702 703 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 704 if (jp == cj) { 705 if (prev != NULL) 706 prev->next = jp->next; 707 else 708 jobmru = jp->next; 709 jp->next = jobmru; 710 jobmru = cj; 711 return; 712 } 713 } 714 cj->next = jobmru; 715 jobmru = cj; 716 } 717 718 static void 719 deljob(struct job *j) 720 { 721 struct job *jp, *prev; 722 723 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 724 if (jp == j) { 725 if (prev != NULL) 726 prev->next = jp->next; 727 else 728 jobmru = jp->next; 729 return; 730 } 731 } 732 } 733 734 /* 735 * Return the most recently used job that isn't `nj', and preferably one 736 * that is stopped. 737 */ 738 static struct job * 739 getcurjob(struct job *nj) 740 { 741 struct job *jp; 742 743 /* Try to find a stopped one.. */ 744 for (jp = jobmru; jp != NULL; jp = jp->next) 745 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 746 return (jp); 747 /* Otherwise the most recently used job that isn't `nj' */ 748 for (jp = jobmru; jp != NULL; jp = jp->next) 749 if (jp->used && jp != nj) 750 return (jp); 751 752 return (NULL); 753 } 754 755 #endif 756 757 /* 758 * Fork of a subshell. If we are doing job control, give the subshell its 759 * own process group. Jp is a job structure that the job is to be added to. 760 * N is the command that will be evaluated by the child. Both jp and n may 761 * be NULL. The mode parameter can be one of the following: 762 * FORK_FG - Fork off a foreground process. 763 * FORK_BG - Fork off a background process. 764 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 765 * process group even if job control is on. 766 * 767 * When job control is turned off, background processes have their standard 768 * input redirected to /dev/null (except for the second and later processes 769 * in a pipeline). 770 */ 771 772 pid_t 773 forkshell(struct job *jp, union node *n, int mode) 774 { 775 pid_t pid; 776 pid_t pgrp; 777 778 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 779 mode)); 780 INTOFF; 781 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 782 checkzombies(); 783 flushall(); 784 pid = fork(); 785 if (pid == -1) { 786 TRACE(("Fork failed, errno=%d\n", errno)); 787 INTON; 788 error("Cannot fork: %s", strerror(errno)); 789 } 790 if (pid == 0) { 791 struct job *p; 792 int wasroot; 793 int i; 794 795 TRACE(("Child shell %d\n", (int)getpid())); 796 wasroot = rootshell; 797 rootshell = 0; 798 handler = &main_handler; 799 closescript(); 800 INTON; 801 clear_traps(); 802 #if JOBS 803 jobctl = 0; /* do job control only in root shell */ 804 if (wasroot && mode != FORK_NOJOB && mflag) { 805 if (jp == NULL || jp->nprocs == 0) 806 pgrp = getpid(); 807 else 808 pgrp = jp->ps[0].pid; 809 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 810 /*** this causes superfluous TIOCSPGRPS ***/ 811 if (tcsetpgrp(ttyfd, pgrp) < 0) 812 error("tcsetpgrp failed, errno=%d", errno); 813 } 814 setsignal(SIGTSTP); 815 setsignal(SIGTTOU); 816 } else if (mode == FORK_BG) { 817 ignoresig(SIGINT); 818 ignoresig(SIGQUIT); 819 if ((jp == NULL || jp->nprocs == 0) && 820 ! fd0_redirected_p ()) { 821 close(0); 822 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 823 error("cannot open %s: %s", 824 _PATH_DEVNULL, strerror(errno)); 825 } 826 } 827 #else 828 if (mode == FORK_BG) { 829 ignoresig(SIGINT); 830 ignoresig(SIGQUIT); 831 if ((jp == NULL || jp->nprocs == 0) && 832 ! fd0_redirected_p ()) { 833 close(0); 834 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 835 error("cannot open %s: %s", 836 _PATH_DEVNULL, strerror(errno)); 837 } 838 } 839 #endif 840 INTOFF; 841 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 842 if (p->used) 843 freejob(p); 844 INTON; 845 if (wasroot && iflag) { 846 setsignal(SIGINT); 847 setsignal(SIGQUIT); 848 setsignal(SIGTERM); 849 } 850 return pid; 851 } 852 if (rootshell && mode != FORK_NOJOB && mflag) { 853 if (jp == NULL || jp->nprocs == 0) 854 pgrp = pid; 855 else 856 pgrp = jp->ps[0].pid; 857 setpgid(pid, pgrp); 858 } 859 if (mode == FORK_BG) { 860 if (bgjob != NULL && bgjob->state == JOBDONE && 861 !bgjob->remembered && !iflag) 862 freejob(bgjob); 863 backgndpid = pid; /* set $! */ 864 bgjob = jp; 865 } 866 if (jp) { 867 struct procstat *ps = &jp->ps[jp->nprocs++]; 868 ps->pid = pid; 869 ps->status = -1; 870 ps->cmd = nullstr; 871 if (iflag && rootshell && n) 872 ps->cmd = commandtext(n); 873 jp->foreground = mode == FORK_FG; 874 #if JOBS 875 setcurjob(jp); 876 #endif 877 } 878 INTON; 879 TRACE(("In parent shell: child = %d\n", (int)pid)); 880 return pid; 881 } 882 883 884 885 /* 886 * Wait for job to finish. 887 * 888 * Under job control we have the problem that while a child process is 889 * running interrupts generated by the user are sent to the child but not 890 * to the shell. This means that an infinite loop started by an inter- 891 * active user may be hard to kill. With job control turned off, an 892 * interactive user may place an interactive program inside a loop. If 893 * the interactive program catches interrupts, the user doesn't want 894 * these interrupts to also abort the loop. The approach we take here 895 * is to have the shell ignore interrupt signals while waiting for a 896 * foreground process to terminate, and then send itself an interrupt 897 * signal if the child process was terminated by an interrupt signal. 898 * Unfortunately, some programs want to do a bit of cleanup and then 899 * exit on interrupt; unless these processes terminate themselves by 900 * sending a signal to themselves (instead of calling exit) they will 901 * confuse this approach. 902 */ 903 904 int 905 waitforjob(struct job *jp, int *origstatus) 906 { 907 #if JOBS 908 pid_t mypgrp = getpgrp(); 909 int propagate_int = jp->jobctl && jp->foreground; 910 #endif 911 int status; 912 int st; 913 914 INTOFF; 915 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 916 while (jp->state == 0) 917 if (dowait(1, jp) == -1) 918 dotrap(); 919 #if JOBS 920 if (jp->jobctl) { 921 if (tcsetpgrp(ttyfd, mypgrp) < 0) 922 error("tcsetpgrp failed, errno=%d\n", errno); 923 } 924 if (jp->state == JOBSTOPPED) 925 setcurjob(jp); 926 #endif 927 status = jp->ps[jp->nprocs - 1].status; 928 if (origstatus != NULL) 929 *origstatus = status; 930 /* convert to 8 bits */ 931 if (WIFEXITED(status)) 932 st = WEXITSTATUS(status); 933 #if JOBS 934 else if (WIFSTOPPED(status)) 935 st = WSTOPSIG(status) + 128; 936 #endif 937 else 938 st = WTERMSIG(status) + 128; 939 if (! JOBS || jp->state == JOBDONE) 940 freejob(jp); 941 if (int_pending()) { 942 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 943 CLEAR_PENDING_INT; 944 } 945 #if JOBS 946 else if (rootshell && iflag && propagate_int && 947 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 948 kill(getpid(), SIGINT); 949 #endif 950 INTON; 951 return st; 952 } 953 954 955 956 /* 957 * Wait for a process to terminate. 958 */ 959 960 static pid_t 961 dowait(int block, struct job *job) 962 { 963 pid_t pid; 964 int status; 965 struct procstat *sp; 966 struct job *jp; 967 struct job *thisjob; 968 int done; 969 int stopped; 970 int sig; 971 int coredump; 972 973 in_dowait++; 974 TRACE(("dowait(%d) called\n", block)); 975 do { 976 pid = waitproc(block, &status); 977 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 978 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 979 (pid > 0 && WIFSTOPPED(status) && !iflag)); 980 in_dowait--; 981 if (pid == -1 && errno == ECHILD && job != NULL) 982 job->state = JOBDONE; 983 if (breakwaitcmd != 0) { 984 breakwaitcmd = 0; 985 if (pid <= 0) 986 return -1; 987 } 988 if (pid <= 0) 989 return pid; 990 INTOFF; 991 thisjob = NULL; 992 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 993 if (jp->used && jp->nprocs > 0) { 994 done = 1; 995 stopped = 1; 996 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 997 if (sp->pid == -1) 998 continue; 999 if (sp->pid == pid) { 1000 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1001 (int)pid, sp->status, 1002 status)); 1003 sp->status = status; 1004 thisjob = jp; 1005 } 1006 if (sp->status == -1) 1007 stopped = 0; 1008 else if (WIFSTOPPED(sp->status)) 1009 done = 0; 1010 } 1011 if (stopped) { /* stopped or done */ 1012 int state = done? JOBDONE : JOBSTOPPED; 1013 if (jp->state != state) { 1014 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1015 jp->state = state; 1016 if (jp != job) { 1017 if (done && !jp->remembered && 1018 !iflag && jp != bgjob) 1019 freejob(jp); 1020 #if JOBS 1021 else if (done) 1022 deljob(jp); 1023 #endif 1024 } 1025 } 1026 } 1027 } 1028 } 1029 INTON; 1030 if (!thisjob || thisjob->state == 0) 1031 ; 1032 else if ((!rootshell || !iflag || thisjob == job) && 1033 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1034 sig = 0; 1035 coredump = 0; 1036 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1037 if (WIFSIGNALED(sp->status)) { 1038 sig = WTERMSIG(sp->status); 1039 coredump = WCOREDUMP(sp->status); 1040 } 1041 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1042 if (sig < sys_nsig && sys_siglist[sig]) 1043 out2str(sys_siglist[sig]); 1044 else 1045 outfmt(out2, "Signal %d", sig); 1046 if (coredump) 1047 out2str(" (core dumped)"); 1048 out2c('\n'); 1049 flushout(out2); 1050 } 1051 } else { 1052 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1053 thisjob->changed = 1; 1054 } 1055 return pid; 1056 } 1057 1058 1059 1060 /* 1061 * Do a wait system call. If job control is compiled in, we accept 1062 * stopped processes. If block is zero, we return a value of zero 1063 * rather than blocking. 1064 */ 1065 static pid_t 1066 waitproc(int block, int *status) 1067 { 1068 int flags; 1069 1070 #if JOBS 1071 flags = WUNTRACED; 1072 #else 1073 flags = 0; 1074 #endif 1075 if (block == 0) 1076 flags |= WNOHANG; 1077 return wait3(status, flags, (struct rusage *)NULL); 1078 } 1079 1080 /* 1081 * return 1 if there are stopped jobs, otherwise 0 1082 */ 1083 int job_warning = 0; 1084 int 1085 stoppedjobs(void) 1086 { 1087 int jobno; 1088 struct job *jp; 1089 1090 if (job_warning) 1091 return (0); 1092 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1093 if (jp->used == 0) 1094 continue; 1095 if (jp->state == JOBSTOPPED) { 1096 out2fmt_flush("You have stopped jobs.\n"); 1097 job_warning = 2; 1098 return (1); 1099 } 1100 } 1101 1102 return (0); 1103 } 1104 1105 1106 static void 1107 checkzombies(void) 1108 { 1109 while (njobs > 0 && dowait(0, NULL) > 0) 1110 ; 1111 } 1112 1113 1114 int 1115 backgndpidset(void) 1116 { 1117 return backgndpid != -1; 1118 } 1119 1120 1121 pid_t 1122 backgndpidval(void) 1123 { 1124 if (bgjob != NULL) 1125 bgjob->remembered = 1; 1126 return backgndpid; 1127 } 1128 1129 /* 1130 * Return a string identifying a command (to be printed by the 1131 * jobs command. 1132 */ 1133 1134 static char *cmdnextc; 1135 static int cmdnleft; 1136 #define MAXCMDTEXT 200 1137 1138 char * 1139 commandtext(union node *n) 1140 { 1141 char *name; 1142 1143 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1144 cmdnleft = MAXCMDTEXT - 4; 1145 cmdtxt(n); 1146 *cmdnextc = '\0'; 1147 return name; 1148 } 1149 1150 1151 static void 1152 cmdtxt(union node *n) 1153 { 1154 union node *np; 1155 struct nodelist *lp; 1156 const char *p; 1157 int i; 1158 char s[2]; 1159 1160 if (n == NULL) 1161 return; 1162 switch (n->type) { 1163 case NSEMI: 1164 cmdtxt(n->nbinary.ch1); 1165 cmdputs("; "); 1166 cmdtxt(n->nbinary.ch2); 1167 break; 1168 case NAND: 1169 cmdtxt(n->nbinary.ch1); 1170 cmdputs(" && "); 1171 cmdtxt(n->nbinary.ch2); 1172 break; 1173 case NOR: 1174 cmdtxt(n->nbinary.ch1); 1175 cmdputs(" || "); 1176 cmdtxt(n->nbinary.ch2); 1177 break; 1178 case NPIPE: 1179 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1180 cmdtxt(lp->n); 1181 if (lp->next) 1182 cmdputs(" | "); 1183 } 1184 break; 1185 case NSUBSHELL: 1186 cmdputs("("); 1187 cmdtxt(n->nredir.n); 1188 cmdputs(")"); 1189 break; 1190 case NREDIR: 1191 case NBACKGND: 1192 cmdtxt(n->nredir.n); 1193 break; 1194 case NIF: 1195 cmdputs("if "); 1196 cmdtxt(n->nif.test); 1197 cmdputs("; then "); 1198 cmdtxt(n->nif.ifpart); 1199 cmdputs("..."); 1200 break; 1201 case NWHILE: 1202 cmdputs("while "); 1203 goto until; 1204 case NUNTIL: 1205 cmdputs("until "); 1206 until: 1207 cmdtxt(n->nbinary.ch1); 1208 cmdputs("; do "); 1209 cmdtxt(n->nbinary.ch2); 1210 cmdputs("; done"); 1211 break; 1212 case NFOR: 1213 cmdputs("for "); 1214 cmdputs(n->nfor.var); 1215 cmdputs(" in ..."); 1216 break; 1217 case NCASE: 1218 cmdputs("case "); 1219 cmdputs(n->ncase.expr->narg.text); 1220 cmdputs(" in ..."); 1221 break; 1222 case NDEFUN: 1223 cmdputs(n->narg.text); 1224 cmdputs("() ..."); 1225 break; 1226 case NCMD: 1227 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1228 cmdtxt(np); 1229 if (np->narg.next) 1230 cmdputs(" "); 1231 } 1232 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1233 cmdputs(" "); 1234 cmdtxt(np); 1235 } 1236 break; 1237 case NARG: 1238 cmdputs(n->narg.text); 1239 break; 1240 case NTO: 1241 p = ">"; i = 1; goto redir; 1242 case NAPPEND: 1243 p = ">>"; i = 1; goto redir; 1244 case NTOFD: 1245 p = ">&"; i = 1; goto redir; 1246 case NCLOBBER: 1247 p = ">|"; i = 1; goto redir; 1248 case NFROM: 1249 p = "<"; i = 0; goto redir; 1250 case NFROMTO: 1251 p = "<>"; i = 0; goto redir; 1252 case NFROMFD: 1253 p = "<&"; i = 0; goto redir; 1254 redir: 1255 if (n->nfile.fd != i) { 1256 s[0] = n->nfile.fd + '0'; 1257 s[1] = '\0'; 1258 cmdputs(s); 1259 } 1260 cmdputs(p); 1261 if (n->type == NTOFD || n->type == NFROMFD) { 1262 if (n->ndup.dupfd >= 0) 1263 s[0] = n->ndup.dupfd + '0'; 1264 else 1265 s[0] = '-'; 1266 s[1] = '\0'; 1267 cmdputs(s); 1268 } else { 1269 cmdtxt(n->nfile.fname); 1270 } 1271 break; 1272 case NHERE: 1273 case NXHERE: 1274 cmdputs("<<..."); 1275 break; 1276 default: 1277 cmdputs("???"); 1278 break; 1279 } 1280 } 1281 1282 1283 1284 static void 1285 cmdputs(const char *s) 1286 { 1287 const char *p; 1288 char *q; 1289 char c; 1290 int subtype = 0; 1291 1292 if (cmdnleft <= 0) 1293 return; 1294 p = s; 1295 q = cmdnextc; 1296 while ((c = *p++) != '\0') { 1297 if (c == CTLESC) 1298 *q++ = *p++; 1299 else if (c == CTLVAR) { 1300 *q++ = '$'; 1301 if (--cmdnleft > 0) 1302 *q++ = '{'; 1303 subtype = *p++; 1304 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1305 *q++ = '#'; 1306 } else if (c == '=' && subtype != 0) { 1307 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1308 if (*q) 1309 q++; 1310 else 1311 cmdnleft++; 1312 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1313 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1314 --cmdnleft > 0) 1315 *q = q[-1], q++; 1316 subtype = 0; 1317 } else if (c == CTLENDVAR) { 1318 *q++ = '}'; 1319 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1320 cmdnleft -= 5; 1321 if (cmdnleft > 0) { 1322 *q++ = '$'; 1323 *q++ = '('; 1324 *q++ = '.'; 1325 *q++ = '.'; 1326 *q++ = '.'; 1327 *q++ = ')'; 1328 } 1329 } else if (c == CTLARI) { 1330 cmdnleft -= 2; 1331 if (cmdnleft > 0) { 1332 *q++ = '$'; 1333 *q++ = '('; 1334 *q++ = '('; 1335 } 1336 p++; 1337 } else if (c == CTLENDARI) { 1338 if (--cmdnleft > 0) { 1339 *q++ = ')'; 1340 *q++ = ')'; 1341 } 1342 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1343 cmdnleft++; /* ignore */ 1344 else 1345 *q++ = c; 1346 if (--cmdnleft <= 0) { 1347 *q++ = '.'; 1348 *q++ = '.'; 1349 *q++ = '.'; 1350 break; 1351 } 1352 } 1353 cmdnextc = q; 1354 } 1355