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 #include "var.h" 74 #include "builtins.h" 75 76 77 static struct job *jobtab; /* array of jobs */ 78 static int njobs; /* size of array */ 79 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 80 MKINIT struct job *bgjob = NULL; /* last background process */ 81 #if JOBS 82 static struct job *jobmru; /* most recently used job list */ 83 static pid_t initialpgrp; /* pgrp of shell on invocation */ 84 #endif 85 int in_waitcmd = 0; /* are we in waitcmd()? */ 86 int in_dowait = 0; /* are we in dowait()? */ 87 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 88 static int ttyfd = -1; 89 90 #if JOBS 91 static void restartjob(struct job *); 92 #endif 93 static void freejob(struct job *); 94 static struct job *getjob(char *); 95 pid_t getjobpgrp(char *); 96 static pid_t dowait(int, struct job *); 97 static pid_t waitproc(int, int *); 98 static void checkzombies(void); 99 static void cmdtxt(union node *); 100 static void cmdputs(const char *); 101 #if JOBS 102 static void setcurjob(struct job *); 103 static void deljob(struct job *); 104 static struct job *getcurjob(struct job *); 105 #endif 106 static void printjobcmd(struct job *); 107 static void showjob(struct job *, int); 108 109 110 /* 111 * Turn job control on and off. 112 */ 113 114 MKINIT int jobctl; 115 116 #if JOBS 117 void 118 setjobctl(int on) 119 { 120 int i; 121 122 if (on == jobctl || rootshell == 0) 123 return; 124 if (on) { 125 if (ttyfd != -1) 126 close(ttyfd); 127 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 128 i = 0; 129 while (i <= 2 && !isatty(i)) 130 i++; 131 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 132 goto out; 133 } 134 if (ttyfd < 10) { 135 /* 136 * Keep our TTY file descriptor out of the way of 137 * the user's redirections. 138 */ 139 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 140 close(ttyfd); 141 ttyfd = -1; 142 goto out; 143 } 144 close(ttyfd); 145 ttyfd = i; 146 } 147 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 148 close(ttyfd); 149 ttyfd = -1; 150 goto out; 151 } 152 do { /* while we are in the background */ 153 initialpgrp = tcgetpgrp(ttyfd); 154 if (initialpgrp < 0) { 155 out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 156 mflag = 0; 157 return; 158 } 159 if (initialpgrp != getpgrp()) { 160 kill(0, SIGTTIN); 161 continue; 162 } 163 } while (0); 164 setsignal(SIGTSTP); 165 setsignal(SIGTTOU); 166 setsignal(SIGTTIN); 167 setpgid(0, rootpid); 168 tcsetpgrp(ttyfd, rootpid); 169 } else { /* turning job control off */ 170 setpgid(0, initialpgrp); 171 tcsetpgrp(ttyfd, initialpgrp); 172 close(ttyfd); 173 ttyfd = -1; 174 setsignal(SIGTSTP); 175 setsignal(SIGTTOU); 176 setsignal(SIGTTIN); 177 } 178 jobctl = on; 179 } 180 #endif 181 182 183 #if JOBS 184 int 185 fgcmd(int argc __unused, char **argv) 186 { 187 struct job *jp; 188 pid_t pgrp; 189 int status; 190 191 jp = getjob(argv[1]); 192 if (jp->jobctl == 0) 193 error("job not created under job control"); 194 printjobcmd(jp); 195 flushout(&output); 196 pgrp = jp->ps[0].pid; 197 tcsetpgrp(ttyfd, pgrp); 198 restartjob(jp); 199 jp->foreground = 1; 200 INTOFF; 201 status = waitforjob(jp, (int *)NULL); 202 INTON; 203 return status; 204 } 205 206 207 int 208 bgcmd(int argc, char **argv) 209 { 210 struct job *jp; 211 212 do { 213 jp = getjob(*++argv); 214 if (jp->jobctl == 0) 215 error("job not created under job control"); 216 if (jp->state == JOBDONE) 217 continue; 218 restartjob(jp); 219 jp->foreground = 0; 220 out1fmt("[%td] ", jp - jobtab + 1); 221 printjobcmd(jp); 222 } while (--argc > 1); 223 return 0; 224 } 225 226 227 static void 228 restartjob(struct job *jp) 229 { 230 struct procstat *ps; 231 int i; 232 233 if (jp->state == JOBDONE) 234 return; 235 setcurjob(jp); 236 INTOFF; 237 kill(-jp->ps[0].pid, SIGCONT); 238 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 239 if (WIFSTOPPED(ps->status)) { 240 ps->status = -1; 241 jp->state = 0; 242 } 243 } 244 INTON; 245 } 246 #endif 247 248 249 int 250 jobscmd(int argc, char *argv[]) 251 { 252 char *id; 253 int ch, mode; 254 255 optind = optreset = 1; 256 opterr = 0; 257 mode = SHOWJOBS_DEFAULT; 258 while ((ch = getopt(argc, argv, "lps")) != -1) { 259 switch (ch) { 260 case 'l': 261 mode = SHOWJOBS_VERBOSE; 262 break; 263 case 'p': 264 mode = SHOWJOBS_PGIDS; 265 break; 266 case 's': 267 mode = SHOWJOBS_PIDS; 268 break; 269 case '?': 270 default: 271 error("unknown option: -%c", optopt); 272 } 273 } 274 argc -= optind; 275 argv += optind; 276 277 if (argc == 0) 278 showjobs(0, mode); 279 else 280 while ((id = *argv++) != NULL) 281 showjob(getjob(id), mode); 282 283 return (0); 284 } 285 286 static void 287 printjobcmd(struct job *jp) 288 { 289 struct procstat *ps; 290 int i; 291 292 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 293 out1str(ps->cmd); 294 if (i > 0) 295 out1str(" | "); 296 } 297 out1c('\n'); 298 } 299 300 static void 301 showjob(struct job *jp, int mode) 302 { 303 char s[64]; 304 char statestr[64]; 305 struct procstat *ps; 306 struct job *j; 307 int col, curr, i, jobno, prev, procno; 308 char c; 309 310 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 311 jobno = jp - jobtab + 1; 312 curr = prev = 0; 313 #if JOBS 314 if ((j = getcurjob(NULL)) != NULL) { 315 curr = j - jobtab + 1; 316 if ((j = getcurjob(j)) != NULL) 317 prev = j - jobtab + 1; 318 } 319 #endif 320 ps = jp->ps + jp->nprocs - 1; 321 if (jp->state == 0) { 322 strcpy(statestr, "Running"); 323 #if JOBS 324 } else if (jp->state == JOBSTOPPED) { 325 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 326 ps--; 327 if (WIFSTOPPED(ps->status)) 328 i = WSTOPSIG(ps->status); 329 else 330 i = -1; 331 if (i > 0 && i < sys_nsig && sys_siglist[i]) 332 strcpy(statestr, sys_siglist[i]); 333 else 334 strcpy(statestr, "Suspended"); 335 #endif 336 } else if (WIFEXITED(ps->status)) { 337 if (WEXITSTATUS(ps->status) == 0) 338 strcpy(statestr, "Done"); 339 else 340 fmtstr(statestr, 64, "Done(%d)", 341 WEXITSTATUS(ps->status)); 342 } else { 343 i = WTERMSIG(ps->status); 344 if (i > 0 && i < sys_nsig && sys_siglist[i]) 345 strcpy(statestr, sys_siglist[i]); 346 else 347 fmtstr(statestr, 64, "Signal %d", i); 348 if (WCOREDUMP(ps->status)) 349 strcat(statestr, " (core dumped)"); 350 } 351 352 for (ps = jp->ps ; ; ps++) { /* for each process */ 353 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 354 out1fmt("%d\n", (int)ps->pid); 355 goto skip; 356 } 357 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 358 goto skip; 359 if (jobno == curr && ps == jp->ps) 360 c = '+'; 361 else if (jobno == prev && ps == jp->ps) 362 c = '-'; 363 else 364 c = ' '; 365 if (ps == jp->ps) 366 fmtstr(s, 64, "[%d] %c ", jobno, c); 367 else 368 fmtstr(s, 64, " %c ", c); 369 out1str(s); 370 col = strlen(s); 371 if (mode == SHOWJOBS_VERBOSE) { 372 fmtstr(s, 64, "%d ", (int)ps->pid); 373 out1str(s); 374 col += strlen(s); 375 } 376 if (ps == jp->ps) { 377 out1str(statestr); 378 col += strlen(statestr); 379 } 380 do { 381 out1c(' '); 382 col++; 383 } while (col < 30); 384 if (mode == SHOWJOBS_VERBOSE) { 385 out1str(ps->cmd); 386 out1c('\n'); 387 } else 388 printjobcmd(jp); 389 skip: if (--procno <= 0) 390 break; 391 } 392 } 393 394 /* 395 * Print a list of jobs. If "change" is nonzero, only print jobs whose 396 * statuses have changed since the last call to showjobs. 397 * 398 * If the shell is interrupted in the process of creating a job, the 399 * result may be a job structure containing zero processes. Such structures 400 * will be freed here. 401 */ 402 403 void 404 showjobs(int change, int mode) 405 { 406 int jobno; 407 struct job *jp; 408 409 TRACE(("showjobs(%d) called\n", change)); 410 checkzombies(); 411 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 412 if (! jp->used) 413 continue; 414 if (jp->nprocs == 0) { 415 freejob(jp); 416 continue; 417 } 418 if (change && ! jp->changed) 419 continue; 420 showjob(jp, mode); 421 jp->changed = 0; 422 /* Hack: discard jobs for which $! has not been referenced 423 * in interactive mode when they terminate. 424 */ 425 if (jp->state == JOBDONE && !jp->remembered && 426 (iflag || jp != bgjob)) { 427 freejob(jp); 428 } 429 } 430 } 431 432 433 /* 434 * Mark a job structure as unused. 435 */ 436 437 static void 438 freejob(struct job *jp) 439 { 440 struct procstat *ps; 441 int i; 442 443 INTOFF; 444 if (bgjob == jp) 445 bgjob = NULL; 446 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 447 if (ps->cmd != nullstr) 448 ckfree(ps->cmd); 449 } 450 if (jp->ps != &jp->ps0) 451 ckfree(jp->ps); 452 jp->used = 0; 453 #if JOBS 454 deljob(jp); 455 #endif 456 INTON; 457 } 458 459 460 461 int 462 waitcmd(int argc, char **argv) 463 { 464 struct job *job; 465 int status, retval; 466 struct job *jp; 467 468 if (argc > 1) { 469 job = getjob(argv[1]); 470 } else { 471 job = NULL; 472 } 473 474 /* 475 * Loop until a process is terminated or stopped, or a SIGINT is 476 * received. 477 */ 478 479 in_waitcmd++; 480 do { 481 if (job != NULL) { 482 if (job->state) { 483 status = job->ps[job->nprocs - 1].status; 484 if (WIFEXITED(status)) 485 retval = WEXITSTATUS(status); 486 #if JOBS 487 else if (WIFSTOPPED(status)) 488 retval = WSTOPSIG(status) + 128; 489 #endif 490 else 491 retval = WTERMSIG(status) + 128; 492 if (! iflag || ! job->changed) 493 freejob(job); 494 else { 495 job->remembered = 0; 496 if (job == bgjob) 497 bgjob = NULL; 498 } 499 in_waitcmd--; 500 return retval; 501 } 502 } else { 503 for (jp = jobtab ; jp < jobtab + njobs; jp++) 504 if (jp->used && jp->state == JOBDONE) { 505 if (! iflag || ! jp->changed) 506 freejob(jp); 507 else { 508 jp->remembered = 0; 509 if (jp == bgjob) 510 bgjob = NULL; 511 } 512 } 513 for (jp = jobtab ; ; jp++) { 514 if (jp >= jobtab + njobs) { /* no running procs */ 515 in_waitcmd--; 516 return 0; 517 } 518 if (jp->used && jp->state == 0) 519 break; 520 } 521 } 522 } while (dowait(1, (struct job *)NULL) != -1); 523 in_waitcmd--; 524 525 return 0; 526 } 527 528 529 530 int 531 jobidcmd(int argc __unused, char **argv) 532 { 533 struct job *jp; 534 int i; 535 536 jp = getjob(argv[1]); 537 for (i = 0 ; i < jp->nprocs ; ) { 538 out1fmt("%d", (int)jp->ps[i].pid); 539 out1c(++i < jp->nprocs? ' ' : '\n'); 540 } 541 return 0; 542 } 543 544 545 546 /* 547 * Convert a job name to a job structure. 548 */ 549 550 static struct job * 551 getjob(char *name) 552 { 553 int jobno; 554 struct job *found, *jp; 555 pid_t pid; 556 int i; 557 558 if (name == NULL) { 559 #if JOBS 560 currentjob: if ((jp = getcurjob(NULL)) == NULL) 561 error("No current job"); 562 return (jp); 563 #else 564 error("No current job"); 565 #endif 566 } else if (name[0] == '%') { 567 if (is_digit(name[1])) { 568 jobno = number(name + 1); 569 if (jobno > 0 && jobno <= njobs 570 && jobtab[jobno - 1].used != 0) 571 return &jobtab[jobno - 1]; 572 #if JOBS 573 } else if (name[1] == '%' && name[2] == '\0') { 574 goto currentjob; 575 } else if (name[1] == '+' && name[2] == '\0') { 576 goto currentjob; 577 } else if (name[1] == '-' && name[2] == '\0') { 578 if ((jp = getcurjob(NULL)) == NULL || 579 (jp = getcurjob(jp)) == NULL) 580 error("No previous job"); 581 return (jp); 582 #endif 583 } else if (name[1] == '?') { 584 found = NULL; 585 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 586 if (jp->used && jp->nprocs > 0 587 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 588 if (found) 589 error("%s: ambiguous", name); 590 found = jp; 591 } 592 } 593 if (found != NULL) 594 return (found); 595 } else { 596 found = NULL; 597 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 598 if (jp->used && jp->nprocs > 0 599 && prefix(name + 1, jp->ps[0].cmd)) { 600 if (found) 601 error("%s: ambiguous", name); 602 found = jp; 603 } 604 } 605 if (found) 606 return found; 607 } 608 } else if (is_number(name)) { 609 pid = (pid_t)number(name); 610 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 611 if (jp->used && jp->nprocs > 0 612 && jp->ps[jp->nprocs - 1].pid == pid) 613 return jp; 614 } 615 } 616 error("No such job: %s", name); 617 /*NOTREACHED*/ 618 return NULL; 619 } 620 621 622 pid_t 623 getjobpgrp(char *name) 624 { 625 struct job *jp; 626 627 jp = getjob(name); 628 return -jp->ps[0].pid; 629 } 630 631 /* 632 * Return a new job structure, 633 */ 634 635 struct job * 636 makejob(union node *node __unused, int nprocs) 637 { 638 int i; 639 struct job *jp; 640 641 for (i = njobs, jp = jobtab ; ; jp++) { 642 if (--i < 0) { 643 INTOFF; 644 if (njobs == 0) { 645 jobtab = ckmalloc(4 * sizeof jobtab[0]); 646 #if JOBS 647 jobmru = NULL; 648 #endif 649 } else { 650 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 651 memcpy(jp, jobtab, njobs * sizeof jp[0]); 652 #if JOBS 653 /* Relocate `next' pointers and list head */ 654 if (jobmru != NULL) 655 jobmru = &jp[jobmru - jobtab]; 656 for (i = 0; i < njobs; i++) 657 if (jp[i].next != NULL) 658 jp[i].next = &jp[jp[i].next - 659 jobtab]; 660 #endif 661 if (bgjob != NULL) 662 bgjob = &jp[bgjob - jobtab]; 663 /* Relocate `ps' pointers */ 664 for (i = 0; i < njobs; i++) 665 if (jp[i].ps == &jobtab[i].ps0) 666 jp[i].ps = &jp[i].ps0; 667 ckfree(jobtab); 668 jobtab = jp; 669 } 670 jp = jobtab + njobs; 671 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 672 INTON; 673 break; 674 } 675 if (jp->used == 0) 676 break; 677 } 678 INTOFF; 679 jp->state = 0; 680 jp->used = 1; 681 jp->changed = 0; 682 jp->nprocs = 0; 683 jp->foreground = 0; 684 jp->remembered = 0; 685 #if JOBS 686 jp->jobctl = jobctl; 687 jp->next = NULL; 688 #endif 689 if (nprocs > 1) { 690 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 691 } else { 692 jp->ps = &jp->ps0; 693 } 694 INTON; 695 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 696 jp - jobtab + 1)); 697 return jp; 698 } 699 700 #if JOBS 701 static void 702 setcurjob(struct job *cj) 703 { 704 struct job *jp, *prev; 705 706 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 707 if (jp == cj) { 708 if (prev != NULL) 709 prev->next = jp->next; 710 else 711 jobmru = jp->next; 712 jp->next = jobmru; 713 jobmru = cj; 714 return; 715 } 716 } 717 cj->next = jobmru; 718 jobmru = cj; 719 } 720 721 static void 722 deljob(struct job *j) 723 { 724 struct job *jp, *prev; 725 726 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 727 if (jp == j) { 728 if (prev != NULL) 729 prev->next = jp->next; 730 else 731 jobmru = jp->next; 732 return; 733 } 734 } 735 } 736 737 /* 738 * Return the most recently used job that isn't `nj', and preferably one 739 * that is stopped. 740 */ 741 static struct job * 742 getcurjob(struct job *nj) 743 { 744 struct job *jp; 745 746 /* Try to find a stopped one.. */ 747 for (jp = jobmru; jp != NULL; jp = jp->next) 748 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 749 return (jp); 750 /* Otherwise the most recently used job that isn't `nj' */ 751 for (jp = jobmru; jp != NULL; jp = jp->next) 752 if (jp->used && jp != nj) 753 return (jp); 754 755 return (NULL); 756 } 757 758 #endif 759 760 /* 761 * Fork of a subshell. If we are doing job control, give the subshell its 762 * own process group. Jp is a job structure that the job is to be added to. 763 * N is the command that will be evaluated by the child. Both jp and n may 764 * be NULL. The mode parameter can be one of the following: 765 * FORK_FG - Fork off a foreground process. 766 * FORK_BG - Fork off a background process. 767 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 768 * process group even if job control is on. 769 * 770 * When job control is turned off, background processes have their standard 771 * input redirected to /dev/null (except for the second and later processes 772 * in a pipeline). 773 */ 774 775 pid_t 776 forkshell(struct job *jp, union node *n, int mode) 777 { 778 pid_t pid; 779 pid_t pgrp; 780 781 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 782 mode)); 783 INTOFF; 784 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 785 checkzombies(); 786 flushall(); 787 pid = fork(); 788 if (pid == -1) { 789 TRACE(("Fork failed, errno=%d\n", errno)); 790 INTON; 791 error("Cannot fork: %s", strerror(errno)); 792 } 793 if (pid == 0) { 794 struct job *p; 795 int wasroot; 796 int i; 797 798 TRACE(("Child shell %d\n", (int)getpid())); 799 wasroot = rootshell; 800 rootshell = 0; 801 handler = &main_handler; 802 closescript(); 803 INTON; 804 forcelocal = 0; 805 clear_traps(); 806 #if JOBS 807 jobctl = 0; /* do job control only in root shell */ 808 if (wasroot && mode != FORK_NOJOB && mflag) { 809 if (jp == NULL || jp->nprocs == 0) 810 pgrp = getpid(); 811 else 812 pgrp = jp->ps[0].pid; 813 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 814 /*** this causes superfluous TIOCSPGRPS ***/ 815 if (tcsetpgrp(ttyfd, pgrp) < 0) 816 error("tcsetpgrp failed, errno=%d", errno); 817 } 818 setsignal(SIGTSTP); 819 setsignal(SIGTTOU); 820 } else if (mode == FORK_BG) { 821 ignoresig(SIGINT); 822 ignoresig(SIGQUIT); 823 if ((jp == NULL || jp->nprocs == 0) && 824 ! fd0_redirected_p ()) { 825 close(0); 826 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 827 error("cannot open %s: %s", 828 _PATH_DEVNULL, strerror(errno)); 829 } 830 } 831 #else 832 if (mode == FORK_BG) { 833 ignoresig(SIGINT); 834 ignoresig(SIGQUIT); 835 if ((jp == NULL || jp->nprocs == 0) && 836 ! fd0_redirected_p ()) { 837 close(0); 838 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 839 error("cannot open %s: %s", 840 _PATH_DEVNULL, strerror(errno)); 841 } 842 } 843 #endif 844 INTOFF; 845 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 846 if (p->used) 847 freejob(p); 848 INTON; 849 if (wasroot && iflag) { 850 setsignal(SIGINT); 851 setsignal(SIGQUIT); 852 setsignal(SIGTERM); 853 } 854 return pid; 855 } 856 if (rootshell && mode != FORK_NOJOB && mflag) { 857 if (jp == NULL || jp->nprocs == 0) 858 pgrp = pid; 859 else 860 pgrp = jp->ps[0].pid; 861 setpgid(pid, pgrp); 862 } 863 if (mode == FORK_BG) { 864 if (bgjob != NULL && bgjob->state == JOBDONE && 865 !bgjob->remembered && !iflag) 866 freejob(bgjob); 867 backgndpid = pid; /* set $! */ 868 bgjob = jp; 869 } 870 if (jp) { 871 struct procstat *ps = &jp->ps[jp->nprocs++]; 872 ps->pid = pid; 873 ps->status = -1; 874 ps->cmd = nullstr; 875 if (iflag && rootshell && n) 876 ps->cmd = commandtext(n); 877 jp->foreground = mode == FORK_FG; 878 #if JOBS 879 setcurjob(jp); 880 #endif 881 } 882 INTON; 883 TRACE(("In parent shell: child = %d\n", (int)pid)); 884 return pid; 885 } 886 887 888 889 /* 890 * Wait for job to finish. 891 * 892 * Under job control we have the problem that while a child process is 893 * running interrupts generated by the user are sent to the child but not 894 * to the shell. This means that an infinite loop started by an inter- 895 * active user may be hard to kill. With job control turned off, an 896 * interactive user may place an interactive program inside a loop. If 897 * the interactive program catches interrupts, the user doesn't want 898 * these interrupts to also abort the loop. The approach we take here 899 * is to have the shell ignore interrupt signals while waiting for a 900 * foreground process to terminate, and then send itself an interrupt 901 * signal if the child process was terminated by an interrupt signal. 902 * Unfortunately, some programs want to do a bit of cleanup and then 903 * exit on interrupt; unless these processes terminate themselves by 904 * sending a signal to themselves (instead of calling exit) they will 905 * confuse this approach. 906 */ 907 908 int 909 waitforjob(struct job *jp, int *origstatus) 910 { 911 #if JOBS 912 pid_t mypgrp = getpgrp(); 913 int propagate_int = jp->jobctl && jp->foreground; 914 #endif 915 int status; 916 int st; 917 918 INTOFF; 919 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 920 while (jp->state == 0) 921 if (dowait(1, jp) == -1) 922 dotrap(); 923 #if JOBS 924 if (jp->jobctl) { 925 if (tcsetpgrp(ttyfd, mypgrp) < 0) 926 error("tcsetpgrp failed, errno=%d\n", errno); 927 } 928 if (jp->state == JOBSTOPPED) 929 setcurjob(jp); 930 #endif 931 status = jp->ps[jp->nprocs - 1].status; 932 if (origstatus != NULL) 933 *origstatus = status; 934 /* convert to 8 bits */ 935 if (WIFEXITED(status)) 936 st = WEXITSTATUS(status); 937 #if JOBS 938 else if (WIFSTOPPED(status)) 939 st = WSTOPSIG(status) + 128; 940 #endif 941 else 942 st = WTERMSIG(status) + 128; 943 if (! JOBS || jp->state == JOBDONE) 944 freejob(jp); 945 if (int_pending()) { 946 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 947 CLEAR_PENDING_INT; 948 } 949 #if JOBS 950 else if (rootshell && iflag && propagate_int && 951 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 952 kill(getpid(), SIGINT); 953 #endif 954 INTON; 955 return st; 956 } 957 958 959 960 /* 961 * Wait for a process to terminate. 962 */ 963 964 static pid_t 965 dowait(int block, struct job *job) 966 { 967 pid_t pid; 968 int status; 969 struct procstat *sp; 970 struct job *jp; 971 struct job *thisjob; 972 int done; 973 int stopped; 974 int sig; 975 int coredump; 976 977 in_dowait++; 978 TRACE(("dowait(%d) called\n", block)); 979 do { 980 pid = waitproc(block, &status); 981 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 982 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 983 (pid > 0 && WIFSTOPPED(status) && !iflag)); 984 in_dowait--; 985 if (pid == -1 && errno == ECHILD && job != NULL) 986 job->state = JOBDONE; 987 if (breakwaitcmd != 0) { 988 breakwaitcmd = 0; 989 if (pid <= 0) 990 return -1; 991 } 992 if (pid <= 0) 993 return pid; 994 INTOFF; 995 thisjob = NULL; 996 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 997 if (jp->used && jp->nprocs > 0) { 998 done = 1; 999 stopped = 1; 1000 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1001 if (sp->pid == -1) 1002 continue; 1003 if (sp->pid == pid) { 1004 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1005 (int)pid, sp->status, 1006 status)); 1007 sp->status = status; 1008 thisjob = jp; 1009 } 1010 if (sp->status == -1) 1011 stopped = 0; 1012 else if (WIFSTOPPED(sp->status)) 1013 done = 0; 1014 } 1015 if (stopped) { /* stopped or done */ 1016 int state = done? JOBDONE : JOBSTOPPED; 1017 if (jp->state != state) { 1018 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1019 jp->state = state; 1020 if (jp != job) { 1021 if (done && !jp->remembered && 1022 !iflag && jp != bgjob) 1023 freejob(jp); 1024 #if JOBS 1025 else if (done) 1026 deljob(jp); 1027 #endif 1028 } 1029 } 1030 } 1031 } 1032 } 1033 INTON; 1034 if (!thisjob || thisjob->state == 0) 1035 ; 1036 else if ((!rootshell || !iflag || thisjob == job) && 1037 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1038 sig = 0; 1039 coredump = 0; 1040 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1041 if (WIFSIGNALED(sp->status)) { 1042 sig = WTERMSIG(sp->status); 1043 coredump = WCOREDUMP(sp->status); 1044 } 1045 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1046 if (sig < sys_nsig && sys_siglist[sig]) 1047 out2str(sys_siglist[sig]); 1048 else 1049 outfmt(out2, "Signal %d", sig); 1050 if (coredump) 1051 out2str(" (core dumped)"); 1052 out2c('\n'); 1053 flushout(out2); 1054 } 1055 } else { 1056 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1057 thisjob->changed = 1; 1058 } 1059 return pid; 1060 } 1061 1062 1063 1064 /* 1065 * Do a wait system call. If job control is compiled in, we accept 1066 * stopped processes. If block is zero, we return a value of zero 1067 * rather than blocking. 1068 */ 1069 static pid_t 1070 waitproc(int block, int *status) 1071 { 1072 int flags; 1073 1074 #if JOBS 1075 flags = WUNTRACED; 1076 #else 1077 flags = 0; 1078 #endif 1079 if (block == 0) 1080 flags |= WNOHANG; 1081 return wait3(status, flags, (struct rusage *)NULL); 1082 } 1083 1084 /* 1085 * return 1 if there are stopped jobs, otherwise 0 1086 */ 1087 int job_warning = 0; 1088 int 1089 stoppedjobs(void) 1090 { 1091 int jobno; 1092 struct job *jp; 1093 1094 if (job_warning) 1095 return (0); 1096 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1097 if (jp->used == 0) 1098 continue; 1099 if (jp->state == JOBSTOPPED) { 1100 out2fmt_flush("You have stopped jobs.\n"); 1101 job_warning = 2; 1102 return (1); 1103 } 1104 } 1105 1106 return (0); 1107 } 1108 1109 1110 static void 1111 checkzombies(void) 1112 { 1113 while (njobs > 0 && dowait(0, NULL) > 0) 1114 ; 1115 } 1116 1117 1118 int 1119 backgndpidset(void) 1120 { 1121 return backgndpid != -1; 1122 } 1123 1124 1125 pid_t 1126 backgndpidval(void) 1127 { 1128 if (bgjob != NULL && !forcelocal) 1129 bgjob->remembered = 1; 1130 return backgndpid; 1131 } 1132 1133 /* 1134 * Return a string identifying a command (to be printed by the 1135 * jobs command. 1136 */ 1137 1138 static char *cmdnextc; 1139 static int cmdnleft; 1140 #define MAXCMDTEXT 200 1141 1142 char * 1143 commandtext(union node *n) 1144 { 1145 char *name; 1146 1147 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1148 cmdnleft = MAXCMDTEXT - 4; 1149 cmdtxt(n); 1150 *cmdnextc = '\0'; 1151 return name; 1152 } 1153 1154 1155 static void 1156 cmdtxt(union node *n) 1157 { 1158 union node *np; 1159 struct nodelist *lp; 1160 const char *p; 1161 int i; 1162 char s[2]; 1163 1164 if (n == NULL) 1165 return; 1166 switch (n->type) { 1167 case NSEMI: 1168 cmdtxt(n->nbinary.ch1); 1169 cmdputs("; "); 1170 cmdtxt(n->nbinary.ch2); 1171 break; 1172 case NAND: 1173 cmdtxt(n->nbinary.ch1); 1174 cmdputs(" && "); 1175 cmdtxt(n->nbinary.ch2); 1176 break; 1177 case NOR: 1178 cmdtxt(n->nbinary.ch1); 1179 cmdputs(" || "); 1180 cmdtxt(n->nbinary.ch2); 1181 break; 1182 case NPIPE: 1183 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1184 cmdtxt(lp->n); 1185 if (lp->next) 1186 cmdputs(" | "); 1187 } 1188 break; 1189 case NSUBSHELL: 1190 cmdputs("("); 1191 cmdtxt(n->nredir.n); 1192 cmdputs(")"); 1193 break; 1194 case NREDIR: 1195 case NBACKGND: 1196 cmdtxt(n->nredir.n); 1197 break; 1198 case NIF: 1199 cmdputs("if "); 1200 cmdtxt(n->nif.test); 1201 cmdputs("; then "); 1202 cmdtxt(n->nif.ifpart); 1203 cmdputs("..."); 1204 break; 1205 case NWHILE: 1206 cmdputs("while "); 1207 goto until; 1208 case NUNTIL: 1209 cmdputs("until "); 1210 until: 1211 cmdtxt(n->nbinary.ch1); 1212 cmdputs("; do "); 1213 cmdtxt(n->nbinary.ch2); 1214 cmdputs("; done"); 1215 break; 1216 case NFOR: 1217 cmdputs("for "); 1218 cmdputs(n->nfor.var); 1219 cmdputs(" in ..."); 1220 break; 1221 case NCASE: 1222 cmdputs("case "); 1223 cmdputs(n->ncase.expr->narg.text); 1224 cmdputs(" in ..."); 1225 break; 1226 case NDEFUN: 1227 cmdputs(n->narg.text); 1228 cmdputs("() ..."); 1229 break; 1230 case NCMD: 1231 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1232 cmdtxt(np); 1233 if (np->narg.next) 1234 cmdputs(" "); 1235 } 1236 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1237 cmdputs(" "); 1238 cmdtxt(np); 1239 } 1240 break; 1241 case NARG: 1242 cmdputs(n->narg.text); 1243 break; 1244 case NTO: 1245 p = ">"; i = 1; goto redir; 1246 case NAPPEND: 1247 p = ">>"; i = 1; goto redir; 1248 case NTOFD: 1249 p = ">&"; i = 1; goto redir; 1250 case NCLOBBER: 1251 p = ">|"; i = 1; goto redir; 1252 case NFROM: 1253 p = "<"; i = 0; goto redir; 1254 case NFROMTO: 1255 p = "<>"; i = 0; goto redir; 1256 case NFROMFD: 1257 p = "<&"; i = 0; goto redir; 1258 redir: 1259 if (n->nfile.fd != i) { 1260 s[0] = n->nfile.fd + '0'; 1261 s[1] = '\0'; 1262 cmdputs(s); 1263 } 1264 cmdputs(p); 1265 if (n->type == NTOFD || n->type == NFROMFD) { 1266 if (n->ndup.dupfd >= 0) 1267 s[0] = n->ndup.dupfd + '0'; 1268 else 1269 s[0] = '-'; 1270 s[1] = '\0'; 1271 cmdputs(s); 1272 } else { 1273 cmdtxt(n->nfile.fname); 1274 } 1275 break; 1276 case NHERE: 1277 case NXHERE: 1278 cmdputs("<<..."); 1279 break; 1280 default: 1281 cmdputs("???"); 1282 break; 1283 } 1284 } 1285 1286 1287 1288 static void 1289 cmdputs(const char *s) 1290 { 1291 const char *p; 1292 char *q; 1293 char c; 1294 int subtype = 0; 1295 1296 if (cmdnleft <= 0) 1297 return; 1298 p = s; 1299 q = cmdnextc; 1300 while ((c = *p++) != '\0') { 1301 if (c == CTLESC) 1302 *q++ = *p++; 1303 else if (c == CTLVAR) { 1304 *q++ = '$'; 1305 if (--cmdnleft > 0) 1306 *q++ = '{'; 1307 subtype = *p++; 1308 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1309 *q++ = '#'; 1310 } else if (c == '=' && subtype != 0) { 1311 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1312 if (*q) 1313 q++; 1314 else 1315 cmdnleft++; 1316 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1317 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1318 --cmdnleft > 0) 1319 *q = q[-1], q++; 1320 subtype = 0; 1321 } else if (c == CTLENDVAR) { 1322 *q++ = '}'; 1323 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1324 cmdnleft -= 5; 1325 if (cmdnleft > 0) { 1326 *q++ = '$'; 1327 *q++ = '('; 1328 *q++ = '.'; 1329 *q++ = '.'; 1330 *q++ = '.'; 1331 *q++ = ')'; 1332 } 1333 } else if (c == CTLARI) { 1334 cmdnleft -= 2; 1335 if (cmdnleft > 0) { 1336 *q++ = '$'; 1337 *q++ = '('; 1338 *q++ = '('; 1339 } 1340 p++; 1341 } else if (c == CTLENDARI) { 1342 if (--cmdnleft > 0) { 1343 *q++ = ')'; 1344 *q++ = ')'; 1345 } 1346 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1347 cmdnleft++; /* ignore */ 1348 else 1349 *q++ = c; 1350 if (--cmdnleft <= 0) { 1351 *q++ = '.'; 1352 *q++ = '.'; 1353 *q++ = '.'; 1354 break; 1355 } 1356 } 1357 cmdnextc = q; 1358 } 1359