jobs.c revision 208881
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 35static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 36#endif 37#endif /* not lint */ 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD: head/bin/sh/jobs.c 208881 2010-06-06 22:27:32Z jilles $"); 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 75STATIC struct job *jobtab; /* array of jobs */ 76STATIC int njobs; /* size of array */ 77MKINIT pid_t backgndpid = -1; /* pid of last background process */ 78#if JOBS 79STATIC struct job *jobmru; /* most recently used job list */ 80STATIC pid_t initialpgrp; /* pgrp of shell on invocation */ 81#endif 82int in_waitcmd = 0; /* are we in waitcmd()? */ 83int in_dowait = 0; /* are we in dowait()? */ 84volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 85static int ttyfd = -1; 86 87#if JOBS 88STATIC void restartjob(struct job *); 89#endif 90STATIC void freejob(struct job *); 91STATIC struct job *getjob(char *); 92STATIC pid_t dowait(int, struct job *); 93STATIC pid_t waitproc(int, int *); 94STATIC void checkzombies(void); 95STATIC void cmdtxt(union node *); 96STATIC void cmdputs(const char *); 97#if JOBS 98STATIC void setcurjob(struct job *); 99STATIC void deljob(struct job *); 100STATIC struct job *getcurjob(struct job *); 101#endif 102STATIC void showjob(struct job *, pid_t, int); 103 104 105/* 106 * Turn job control on and off. 107 */ 108 109MKINIT int jobctl; 110 111#if JOBS 112void 113setjobctl(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) { 150out: 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 181INCLUDE <sys/types.h> 182INCLUDE <stdlib.h> 183 184SHELLPROC { 185 backgndpid = -1; 186#if JOBS 187 jobctl = 0; 188#endif 189} 190 191#endif 192 193 194 195#if JOBS 196int 197fgcmd(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 220int 221bgcmd(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 243STATIC void 244restartjob(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 265int 266jobscmd(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 302STATIC void 303showjob(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'); 383skip: 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 397void 398showjobs(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 427STATIC void 428freejob(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 449int 450waitcmd(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 503int 504jobidcmd(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 523STATIC struct job * 524getjob(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 533currentjob: 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 600struct job * 601makejob(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 663STATIC void 664setcurjob(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 683STATIC void 684deljob(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 */ 703STATIC struct job * 704getcurjob(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 737pid_t 738forkshell(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 864int 865waitforjob(struct job *jp, int *origstatus) 866{ 867#if JOBS 868 pid_t mypgrp = getpgrp(); 869 int propagate_int = jp->jobctl && jp->foreground; 870#endif 871 int status; 872 int st; 873 874 INTOFF; 875 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 876 while (jp->state == 0) 877 if (dowait(1, jp) == -1) 878 dotrap(); 879#if JOBS 880 if (jp->jobctl) { 881 if (tcsetpgrp(ttyfd, mypgrp) < 0) 882 error("tcsetpgrp failed, errno=%d\n", errno); 883 } 884 if (jp->state == JOBSTOPPED) 885 setcurjob(jp); 886#endif 887 status = jp->ps[jp->nprocs - 1].status; 888 if (origstatus != NULL) 889 *origstatus = status; 890 /* convert to 8 bits */ 891 if (WIFEXITED(status)) 892 st = WEXITSTATUS(status); 893#if JOBS 894 else if (WIFSTOPPED(status)) 895 st = WSTOPSIG(status) + 128; 896#endif 897 else 898 st = WTERMSIG(status) + 128; 899 if (! JOBS || jp->state == JOBDONE) 900 freejob(jp); 901 if (int_pending()) { 902 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 903 kill(getpid(), SIGINT); 904 else 905 CLEAR_PENDING_INT; 906 } 907#if JOBS 908 else if (rootshell && iflag && propagate_int && 909 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 910 kill(getpid(), SIGINT); 911#endif 912 INTON; 913 return st; 914} 915 916 917 918/* 919 * Wait for a process to terminate. 920 */ 921 922STATIC pid_t 923dowait(int block, struct job *job) 924{ 925 pid_t pid; 926 int status; 927 struct procstat *sp; 928 struct job *jp; 929 struct job *thisjob; 930 int done; 931 int stopped; 932 int sig; 933 int i; 934 935 in_dowait++; 936 TRACE(("dowait(%d) called\n", block)); 937 do { 938 pid = waitproc(block, &status); 939 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 940 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 941 (pid > 0 && WIFSTOPPED(status) && !iflag)); 942 in_dowait--; 943 if (pid == -1 && errno == ECHILD && job != NULL) 944 job->state = JOBDONE; 945 if (breakwaitcmd != 0) { 946 breakwaitcmd = 0; 947 if (pid <= 0) 948 return -1; 949 } 950 if (pid <= 0) 951 return pid; 952 INTOFF; 953 thisjob = NULL; 954 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 955 if (jp->used) { 956 done = 1; 957 stopped = 1; 958 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 959 if (sp->pid == -1) 960 continue; 961 if (sp->pid == pid) { 962 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 963 (int)pid, sp->status, 964 status)); 965 sp->status = status; 966 thisjob = jp; 967 } 968 if (sp->status == -1) 969 stopped = 0; 970 else if (WIFSTOPPED(sp->status)) 971 done = 0; 972 } 973 if (stopped) { /* stopped or done */ 974 int state = done? JOBDONE : JOBSTOPPED; 975 if (jp->state != state) { 976 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 977 jp->state = state; 978#if JOBS 979 if (done) 980 deljob(jp); 981#endif 982 } 983 } 984 } 985 } 986 INTON; 987 if (! rootshell || ! iflag || (job && thisjob == job)) { 988#if JOBS 989 if (WIFSTOPPED(status)) 990 sig = WSTOPSIG(status); 991 else 992#endif 993 { 994 if (WIFEXITED(status)) 995 sig = 0; 996 else 997 sig = WTERMSIG(status); 998 } 999 if (sig != 0 && sig != SIGINT && sig != SIGPIPE) { 1000 if (!mflag || 1001 (thisjob->foreground && !WIFSTOPPED(status))) { 1002 i = WTERMSIG(status); 1003 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F]) 1004 out1str(sys_siglist[i & 0x7F]); 1005 else 1006 out1fmt("Signal %d", i & 0x7F); 1007 if (WCOREDUMP(status)) 1008 out1str(" (core dumped)"); 1009 out1c('\n'); 1010 } else 1011 showjob(thisjob, pid, SHOWJOBS_DEFAULT); 1012 } 1013 } else { 1014 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1015 if (thisjob) 1016 thisjob->changed = 1; 1017 } 1018 return pid; 1019} 1020 1021 1022 1023/* 1024 * Do a wait system call. If job control is compiled in, we accept 1025 * stopped processes. If block is zero, we return a value of zero 1026 * rather than blocking. 1027 */ 1028STATIC pid_t 1029waitproc(int block, int *status) 1030{ 1031 int flags; 1032 1033#if JOBS 1034 flags = WUNTRACED; 1035#else 1036 flags = 0; 1037#endif 1038 if (block == 0) 1039 flags |= WNOHANG; 1040 return wait3(status, flags, (struct rusage *)NULL); 1041} 1042 1043/* 1044 * return 1 if there are stopped jobs, otherwise 0 1045 */ 1046int job_warning = 0; 1047int 1048stoppedjobs(void) 1049{ 1050 int jobno; 1051 struct job *jp; 1052 1053 if (job_warning) 1054 return (0); 1055 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1056 if (jp->used == 0) 1057 continue; 1058 if (jp->state == JOBSTOPPED) { 1059 out2fmt_flush("You have stopped jobs.\n"); 1060 job_warning = 2; 1061 return (1); 1062 } 1063 } 1064 1065 return (0); 1066} 1067 1068 1069STATIC void 1070checkzombies(void) 1071{ 1072 while (njobs > 0 && dowait(0, NULL) > 0) 1073 ; 1074} 1075 1076 1077/* 1078 * Return a string identifying a command (to be printed by the 1079 * jobs command. 1080 */ 1081 1082STATIC char *cmdnextc; 1083STATIC int cmdnleft; 1084#define MAXCMDTEXT 200 1085 1086char * 1087commandtext(union node *n) 1088{ 1089 char *name; 1090 1091 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1092 cmdnleft = MAXCMDTEXT - 4; 1093 cmdtxt(n); 1094 *cmdnextc = '\0'; 1095 return name; 1096} 1097 1098 1099STATIC void 1100cmdtxt(union node *n) 1101{ 1102 union node *np; 1103 struct nodelist *lp; 1104 const char *p; 1105 int i; 1106 char s[2]; 1107 1108 if (n == NULL) 1109 return; 1110 switch (n->type) { 1111 case NSEMI: 1112 cmdtxt(n->nbinary.ch1); 1113 cmdputs("; "); 1114 cmdtxt(n->nbinary.ch2); 1115 break; 1116 case NAND: 1117 cmdtxt(n->nbinary.ch1); 1118 cmdputs(" && "); 1119 cmdtxt(n->nbinary.ch2); 1120 break; 1121 case NOR: 1122 cmdtxt(n->nbinary.ch1); 1123 cmdputs(" || "); 1124 cmdtxt(n->nbinary.ch2); 1125 break; 1126 case NPIPE: 1127 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1128 cmdtxt(lp->n); 1129 if (lp->next) 1130 cmdputs(" | "); 1131 } 1132 break; 1133 case NSUBSHELL: 1134 cmdputs("("); 1135 cmdtxt(n->nredir.n); 1136 cmdputs(")"); 1137 break; 1138 case NREDIR: 1139 case NBACKGND: 1140 cmdtxt(n->nredir.n); 1141 break; 1142 case NIF: 1143 cmdputs("if "); 1144 cmdtxt(n->nif.test); 1145 cmdputs("; then "); 1146 cmdtxt(n->nif.ifpart); 1147 cmdputs("..."); 1148 break; 1149 case NWHILE: 1150 cmdputs("while "); 1151 goto until; 1152 case NUNTIL: 1153 cmdputs("until "); 1154until: 1155 cmdtxt(n->nbinary.ch1); 1156 cmdputs("; do "); 1157 cmdtxt(n->nbinary.ch2); 1158 cmdputs("; done"); 1159 break; 1160 case NFOR: 1161 cmdputs("for "); 1162 cmdputs(n->nfor.var); 1163 cmdputs(" in ..."); 1164 break; 1165 case NCASE: 1166 cmdputs("case "); 1167 cmdputs(n->ncase.expr->narg.text); 1168 cmdputs(" in ..."); 1169 break; 1170 case NDEFUN: 1171 cmdputs(n->narg.text); 1172 cmdputs("() ..."); 1173 break; 1174 case NCMD: 1175 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1176 cmdtxt(np); 1177 if (np->narg.next) 1178 cmdputs(" "); 1179 } 1180 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1181 cmdputs(" "); 1182 cmdtxt(np); 1183 } 1184 break; 1185 case NARG: 1186 cmdputs(n->narg.text); 1187 break; 1188 case NTO: 1189 p = ">"; i = 1; goto redir; 1190 case NAPPEND: 1191 p = ">>"; i = 1; goto redir; 1192 case NTOFD: 1193 p = ">&"; i = 1; goto redir; 1194 case NCLOBBER: 1195 p = ">|"; i = 1; goto redir; 1196 case NFROM: 1197 p = "<"; i = 0; goto redir; 1198 case NFROMTO: 1199 p = "<>"; i = 0; goto redir; 1200 case NFROMFD: 1201 p = "<&"; i = 0; goto redir; 1202redir: 1203 if (n->nfile.fd != i) { 1204 s[0] = n->nfile.fd + '0'; 1205 s[1] = '\0'; 1206 cmdputs(s); 1207 } 1208 cmdputs(p); 1209 if (n->type == NTOFD || n->type == NFROMFD) { 1210 if (n->ndup.dupfd >= 0) 1211 s[0] = n->ndup.dupfd + '0'; 1212 else 1213 s[0] = '-'; 1214 s[1] = '\0'; 1215 cmdputs(s); 1216 } else { 1217 cmdtxt(n->nfile.fname); 1218 } 1219 break; 1220 case NHERE: 1221 case NXHERE: 1222 cmdputs("<<..."); 1223 break; 1224 default: 1225 cmdputs("???"); 1226 break; 1227 } 1228} 1229 1230 1231 1232STATIC void 1233cmdputs(const char *s) 1234{ 1235 const char *p; 1236 char *q; 1237 char c; 1238 int subtype = 0; 1239 1240 if (cmdnleft <= 0) 1241 return; 1242 p = s; 1243 q = cmdnextc; 1244 while ((c = *p++) != '\0') { 1245 if (c == CTLESC) 1246 *q++ = *p++; 1247 else if (c == CTLVAR) { 1248 *q++ = '$'; 1249 if (--cmdnleft > 0) 1250 *q++ = '{'; 1251 subtype = *p++; 1252 } else if (c == '=' && subtype != 0) { 1253 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL]; 1254 subtype = 0; 1255 } else if (c == CTLENDVAR) { 1256 *q++ = '}'; 1257 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) 1258 cmdnleft++; /* ignore it */ 1259 else 1260 *q++ = c; 1261 if (--cmdnleft <= 0) { 1262 *q++ = '.'; 1263 *q++ = '.'; 1264 *q++ = '.'; 1265 break; 1266 } 1267 } 1268 cmdnextc = q; 1269} 1270