jobs.c revision 1.123
1 /* $NetBSD: jobs.c,v 1.123 2024/10/09 13:43:32 kre Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 39 #else 40 __RCSID("$NetBSD: jobs.c,v 1.123 2024/10/09 13:43:32 kre Exp $"); 41 #endif 42 #endif /* not lint */ 43 44 #include <stdio.h> 45 #include <fcntl.h> 46 #include <signal.h> 47 #include <errno.h> 48 #include <unistd.h> 49 #include <stdlib.h> 50 #include <paths.h> 51 #include <sys/types.h> 52 #include <sys/param.h> 53 #ifdef BSD 54 #include <sys/wait.h> 55 #include <sys/time.h> 56 #include <sys/resource.h> 57 #endif 58 #include <sys/ioctl.h> 59 60 #include "shell.h" 61 #if JOBS 62 #if OLD_TTY_DRIVER 63 #include "sgtty.h" 64 #else 65 #include <termios.h> 66 #endif 67 #undef CEOF /* syntax.h redefines this */ 68 #endif 69 #include "redir.h" 70 #include "show.h" 71 #include "main.h" 72 #include "parser.h" 73 #include "nodes.h" 74 #include "jobs.h" 75 #include "var.h" 76 #include "options.h" 77 #include "builtins.h" 78 #include "trap.h" 79 #include "syntax.h" 80 #include "input.h" 81 #include "output.h" 82 #include "memalloc.h" 83 #include "error.h" 84 #include "mystring.h" 85 86 87 #ifndef WCONTINUED 88 #define WCONTINUED 0 /* So we can compile on old systems */ 89 #endif 90 #ifndef WIFCONTINUED 91 #define WIFCONTINUED(x) (0) /* ditto */ 92 #endif 93 94 95 static struct job *jobtab; /* array of jobs */ 96 static int njobs; /* size of array */ 97 static int jobs_invalid; /* set in child */ 98 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 99 #if JOBS 100 int initialpgrp; /* pgrp of shell on invocation */ 101 static int curjob = -1; /* current job */ 102 #endif 103 static int ttyfd = -1; 104 105 STATIC void restartjob(struct job *); 106 STATIC void freejob(struct job *); 107 STATIC struct job *getjob(const char *, int); 108 STATIC int dowait(int, struct job *, struct job **); 109 #define WBLOCK 1 110 #define WNOFREE 2 111 #define WSILENT 4 112 STATIC int jobstatus(const struct job *, int); 113 STATIC int waitproc(int, struct job *, int *); 114 STATIC int cmdtxt(union node *, int); 115 STATIC void cmdlist(union node *, int); 116 STATIC void cmdputs(const char *); 117 inline static void cmdputi(int); 118 119 #define JNUM(j) ((int)((j) != NULL ? ((j) - jobtab) + 1 : 0)) 120 121 #ifdef SYSV 122 STATIC int onsigchild(void); 123 #endif 124 125 #ifdef OLD_TTY_DRIVER 126 static pid_t tcgetpgrp(int fd); 127 static int tcsetpgrp(int fd, pid_t pgrp); 128 129 static pid_t 130 tcgetpgrp(int fd) 131 { 132 pid_t pgrp; 133 if (ioctl(fd, TIOCGPGRP, (char *)&pgrp) == -1) 134 return -1; 135 else 136 return pgrp; 137 } 138 139 static int 140 tcsetpgrp(int fd, pid_tpgrp) 141 { 142 return ioctl(fd, TIOCSPGRP, (char *)&pgrp); 143 } 144 #endif 145 146 static void 147 ttyfd_change(int from, int to) 148 { 149 if (ttyfd == from) 150 ttyfd = to; 151 } 152 153 /* 154 * Turn job control on and off. 155 * 156 * Note: This code assumes that the third arg to ioctl is a character 157 * pointer, which is true on Berkeley systems but not System V. Since 158 * System V doesn't have job control yet, this isn't a problem now. 159 */ 160 161 MKINIT int jobctl; 162 163 void 164 setjobctl(int on) 165 { 166 #ifdef OLD_TTY_DRIVER 167 int ldisc; 168 #endif 169 170 if (on == jobctl || rootshell == 0) 171 return; 172 if (on) { 173 #if defined(FIOCLEX) || defined(FD_CLOEXEC) 174 int i; 175 176 if (ttyfd != -1) 177 sh_close(ttyfd); 178 if ((ttyfd = open("/dev/tty", O_RDWR)) == -1) { 179 for (i = 0; i < 3; i++) { 180 if (isatty(i) && (ttyfd = dup(i)) != -1) 181 break; 182 } 183 if (i == 3) 184 goto out; 185 } 186 ttyfd = to_upper_fd(ttyfd); /* Move to a high fd */ 187 register_sh_fd(ttyfd, ttyfd_change); 188 #else 189 out2str("sh: Need FIOCLEX or FD_CLOEXEC to support job control"); 190 goto out; 191 #endif 192 if ((initialpgrp = tcgetpgrp(ttyfd)) < 0) { 193 out: 194 out2str("sh: can't access tty; job control turned off\n"); 195 mflag = 0; 196 return; 197 } 198 if (initialpgrp == -1) 199 initialpgrp = getpgrp(); 200 else if (initialpgrp != getpgrp()) 201 killpg(0, SIGTTIN); 202 203 #ifdef OLD_TTY_DRIVER 204 if (ioctl(ttyfd, TIOCGETD, (char *)&ldisc) < 0 205 || ldisc != NTTYDISC) { 206 out2str("sh: need new tty driver to run job control; job control turned off\n"); 207 mflag = 0; 208 return; 209 } 210 #endif 211 setsignal(SIGTSTP, 0); 212 setsignal(SIGTTOU, 0); 213 setsignal(SIGTTIN, 0); 214 if (getpgrp() != rootpid && setpgid(0, rootpid) == -1) 215 error("Cannot set process group (%s) at %d", 216 strerror(errno), __LINE__); 217 if (tcsetpgrp(ttyfd, rootpid) == -1) 218 error("Cannot set tty process group (%s) at %d", 219 strerror(errno), __LINE__); 220 } else { /* turning job control off */ 221 if (getpgrp() != initialpgrp && setpgid(0, initialpgrp) == -1) 222 error("Cannot set process group (%s) at %d", 223 strerror(errno), __LINE__); 224 if (tcsetpgrp(ttyfd, initialpgrp) == -1) 225 error("Cannot set tty process group (%s) at %d", 226 strerror(errno), __LINE__); 227 sh_close(ttyfd); 228 ttyfd = -1; 229 setsignal(SIGTSTP, 0); 230 setsignal(SIGTTOU, 0); 231 setsignal(SIGTTIN, 0); 232 } 233 jobctl = on; 234 } 235 236 237 #ifdef mkinit 238 INCLUDE <stdlib.h> 239 240 SHELLPROC { 241 backgndpid = -1; 242 #if JOBS 243 jobctl = 0; 244 #endif 245 } 246 247 #endif 248 249 250 251 #if JOBS 252 static int 253 do_fgcmd(const char *arg_ptr) 254 { 255 struct job *jp; 256 int i; 257 int status; 258 259 if (jobs_invalid) 260 error("No current jobs"); 261 jp = getjob(arg_ptr, 0); 262 if (jp->jobctl == 0) 263 error("job not created under job control"); 264 out1fmt("%s", jp->ps[0].cmd); 265 for (i = 1; i < jp->nprocs; i++) 266 out1fmt(" | %s", jp->ps[i].cmd ); 267 out1c('\n'); 268 flushall(); 269 270 if (tcsetpgrp(ttyfd, jp->pgrp) == -1) { 271 error("Cannot set tty process group (%s) at %d", 272 strerror(errno), __LINE__); 273 } 274 INTOFF; 275 restartjob(jp); 276 status = waitforjob(jp); 277 INTON; 278 return status; 279 } 280 281 int 282 fgcmd(int argc, char **argv) 283 { 284 nextopt(""); 285 return do_fgcmd(*argptr); 286 } 287 288 int 289 fgcmd_percent(int argc, char **argv) 290 { 291 nextopt(""); 292 return do_fgcmd(*argv); 293 } 294 295 static void 296 set_curjob(struct job *jp, int mode) 297 { 298 struct job *jp1, *jp2; 299 int i, ji; 300 301 ji = jp - jobtab; 302 303 /* first remove from list */ 304 if (ji == curjob) 305 curjob = jp->prev_job; 306 else { 307 for (i = 0; i < njobs; i++) { 308 if (jobtab[i].prev_job != ji) 309 continue; 310 jobtab[i].prev_job = jp->prev_job; 311 break; 312 } 313 } 314 315 /* Then re-insert in correct position */ 316 switch (mode) { 317 case 0: /* job being deleted */ 318 jp->prev_job = -1; 319 break; 320 case 1: /* newly created job or backgrounded job, 321 put after all stopped jobs. */ 322 if (curjob != -1 && jobtab[curjob].state == JOBSTOPPED) { 323 for (jp1 = jobtab + curjob; ; jp1 = jp2) { 324 if (jp1->prev_job == -1) 325 break; 326 jp2 = jobtab + jp1->prev_job; 327 if (jp2->state != JOBSTOPPED) 328 break; 329 } 330 jp->prev_job = jp1->prev_job; 331 jp1->prev_job = ji; 332 break; 333 } 334 /* FALLTHROUGH */ 335 case 2: /* newly stopped job - becomes curjob */ 336 jp->prev_job = curjob; 337 curjob = ji; 338 break; 339 } 340 } 341 342 int 343 bgcmd(int argc, char **argv) 344 { 345 struct job *jp; 346 int i; 347 348 nextopt(""); 349 if (jobs_invalid) 350 error("No current jobs"); 351 do { 352 jp = getjob(*argptr, 0); 353 if (jp->jobctl == 0) 354 error("job not created under job control"); 355 set_curjob(jp, 1); 356 out1fmt("[%d] %s", JNUM(jp), jp->ps[0].cmd); 357 for (i = 1; i < jp->nprocs; i++) 358 out1fmt(" | %s", jp->ps[i].cmd ); 359 out1c('\n'); 360 flushall(); 361 restartjob(jp); 362 } while (*argptr && *++argptr); 363 return 0; 364 } 365 366 367 STATIC void 368 restartjob(struct job *jp) 369 { 370 struct procstat *ps; 371 int i, e; 372 373 if (jp->state == JOBDONE) 374 return; 375 if (jp->pgrp == 0) 376 error("Job [%d] does not have a process group", JNUM(jp)); 377 378 INTOFF; 379 for (e = i = 0; i < jp->nprocs; i++) { 380 /* 381 * Don't touch a process we already waited for and collected 382 * exit status, that pid may have been reused for something 383 * else - even another of our jobs 384 */ 385 if (jp->ps[i].status != -1 && !WIFSTOPPED(jp->ps[i].status)) 386 continue; 387 388 /* 389 * Otherwise tell it to continue, if it worked, we're done 390 * (we signal the whole process group) 391 */ 392 if (killpg(jp->pgrp, SIGCONT) != -1) 393 break; 394 e = errno; 395 break; /* no point trying again */ 396 } 397 398 if (e != 0) 399 error("Cannot continue job (%s)", strerror(e)); 400 else if (i >= jp->nprocs) 401 error("Job [%d] has no stopped processes", JNUM(jp)); 402 403 /* 404 * Now change state of all stopped processes in the job to running 405 * If there were any, the job is now running as well. 406 */ 407 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 408 if (WIFSTOPPED(ps->status)) { 409 VTRACE(DBG_JOBS, ( 410 "restartjob: [%d] pid %d status change" 411 " from %#x (stopped) to -1 (running)\n", 412 JNUM(jp), ps->pid, ps->status)); 413 ps->status = -1; 414 jp->state = JOBRUNNING; 415 } 416 } 417 INTON; 418 } 419 #endif 420 421 inline static void 422 cmdputi(int n) 423 { 424 char str[20]; 425 426 fmtstr(str, sizeof str, "%d", n); 427 cmdputs(str); 428 } 429 430 static void 431 showjob(struct output *out, struct job *jp, int mode) 432 { 433 int procno; 434 int st; 435 struct procstat *ps; 436 int col; 437 char s[64]; 438 439 #if JOBS 440 if (mode & SHOW_PGID) { 441 /* output only the process group ID (lead process ID) */ 442 outfmt(out, "%ld\n", 443 jp->pgrp != 0 ? (long)jp->pgrp : (long)jp->ps->pid); 444 return; 445 } 446 #endif 447 448 procno = jp->nprocs; 449 if (!procno) 450 return; 451 452 if (mode & SHOW_PID) 453 mode |= SHOW_MULTILINE; 454 455 if ((procno > 1 && !(mode & SHOW_MULTILINE)) 456 || (mode & SHOW_SIGNALLED)) { 457 /* See if we have more than one status to report */ 458 ps = jp->ps; 459 st = ps->status; 460 do { 461 int st1 = ps->status; 462 if (st1 != st) 463 /* yes - need multi-line output */ 464 mode |= SHOW_MULTILINE; 465 if (st1 == -1 || !(mode & SHOW_SIGNALLED) || WIFEXITED(st1)) 466 continue; 467 if (WIFSTOPPED(st1) || ((st1 = WTERMSIG(st1) & 0x7f) 468 && st1 != SIGINT && st1 != SIGPIPE)) 469 mode |= SHOW_ISSIG; 470 471 } while (ps++, --procno); 472 procno = jp->nprocs; 473 } 474 475 if (mode & SHOW_SIGNALLED && !(mode & SHOW_ISSIG)) { 476 if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE)) { 477 VTRACE(DBG_JOBS, ("showjob: freeing job %d\n", 478 JNUM(jp))); 479 freejob(jp); 480 } 481 return; 482 } 483 484 for (ps = jp->ps; --procno >= 0; ps++) { /* for each process */ 485 if (ps == jp->ps) 486 fmtstr(s, 16, "[%d] %c ", 487 JNUM(jp), 488 #if JOBS 489 jp - jobtab == curjob ? 490 '+' : 491 curjob != -1 && 492 jp - jobtab == jobtab[curjob].prev_job ? 493 '-' : 494 #endif 495 ' '); 496 else 497 fmtstr(s, 16, " " ); 498 col = strlen(s); 499 if (mode & SHOW_PID) { 500 fmtstr(s + col, 16, "%ld ", (long)ps->pid); 501 col += strlen(s + col); 502 } 503 if (ps->status == -1) { 504 scopy("Running", s + col); 505 } else if (WIFEXITED(ps->status)) { 506 st = WEXITSTATUS(ps->status); 507 if (st) 508 fmtstr(s + col, 16, "Done(%d)", st); 509 else 510 fmtstr(s + col, 16, "Done"); 511 } else { 512 #if JOBS 513 if (WIFSTOPPED(ps->status)) 514 st = WSTOPSIG(ps->status); 515 else /* WIFSIGNALED(ps->status) */ 516 #endif 517 st = WTERMSIG(ps->status); 518 scopyn(strsignal(st), s + col, 32); 519 if (WCOREDUMP(ps->status)) { 520 col += strlen(s + col); 521 scopyn(" (core dumped)", s + col, 64 - col); 522 } 523 } 524 col += strlen(s + col); 525 outstr(s, out); 526 do { 527 outc(' ', out); 528 col++; 529 } while (col < 30); 530 outstr(ps->cmd, out); 531 if (mode & SHOW_MULTILINE) { 532 if (procno > 0) { 533 outc(' ', out); 534 outc('|', out); 535 } 536 } else { 537 while (--procno >= 0) 538 outfmt(out, " | %s", (++ps)->cmd ); 539 } 540 outc('\n', out); 541 } 542 flushout(out); 543 jp->flags &= ~JOBCHANGED; 544 if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE)) 545 freejob(jp); 546 } 547 548 int 549 jobscmd(int argc, char **argv) 550 { 551 int mode, m; 552 553 mode = 0; 554 while ((m = nextopt("lpZ"))) 555 switch (m) { 556 case 'l': 557 mode = SHOW_PID; 558 break; 559 case 'p': 560 mode = SHOW_PGID; 561 break; 562 case 'Z': 563 mode = SHOW_PROCTITLE; 564 break; 565 } 566 567 if (mode == SHOW_PROCTITLE) { 568 if (*argptr && **argptr) 569 setproctitle("%s", *argptr); 570 else 571 setproctitle(NULL); 572 return 0; 573 } 574 575 if (!iflag && !posix) 576 mode |= SHOW_NO_FREE; 577 578 if (*argptr) { 579 do 580 showjob(out1, getjob(*argptr,0), mode); 581 while (*++argptr); 582 } else 583 showjobs(out1, mode); 584 return 0; 585 } 586 587 588 /* 589 * Print a list of jobs. If "change" is nonzero, only print jobs whose 590 * statuses have changed since the last call to showjobs. 591 * 592 * If the shell is interrupted in the process of creating a job, the 593 * result may be a job structure containing zero processes. Such structures 594 * will be freed here. 595 */ 596 597 void 598 showjobs(struct output *out, int mode) 599 { 600 int jobno; 601 struct job *jp; 602 int silent = 0, gotpid; 603 604 CTRACE(DBG_JOBS, ("showjobs(%x) called\n", mode)); 605 606 /* Collect everything pending in the kernel */ 607 if ((gotpid = dowait(WSILENT, NULL, NULL)) > 0) 608 while (dowait(WSILENT, NULL, NULL) > 0) 609 continue; 610 #ifdef JOBS 611 /* 612 * Check if we are not in our foreground group, and if not 613 * put us in it. 614 */ 615 if (mflag && gotpid != -1 && tcgetpgrp(ttyfd) != getpid()) { 616 if (tcsetpgrp(ttyfd, getpid()) == -1) 617 error("Cannot set tty process group (%s) at %d", 618 strerror(errno), __LINE__); 619 VTRACE(DBG_JOBS|DBG_INPUT, ("repaired tty process group\n")); 620 silent = 1; 621 } 622 #endif 623 624 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 625 if (!jp->used) 626 continue; 627 if (jp->nprocs == 0) { 628 if (!jobs_invalid) 629 freejob(jp); 630 continue; 631 } 632 if ((mode & SHOW_CHANGED) && !(jp->flags & JOBCHANGED)) 633 continue; 634 if (silent && (jp->flags & JOBCHANGED)) { 635 jp->flags &= ~JOBCHANGED; 636 continue; 637 } 638 showjob(out, jp, mode); 639 } 640 } 641 642 /* 643 * Mark a job structure as unused. 644 */ 645 646 STATIC void 647 freejob(struct job *jp) 648 { 649 INTOFF; 650 if (jp->ps != &jp->ps0) { 651 ckfree(jp->ps); 652 jp->ps = &jp->ps0; 653 } 654 jp->nprocs = 0; 655 jp->used = 0; 656 #if JOBS 657 set_curjob(jp, 0); 658 #endif 659 INTON; 660 } 661 662 /* 663 * Extract the status of a completed job (for $?) 664 */ 665 STATIC int 666 jobstatus(const struct job *jp, int raw) 667 { 668 int status = 0; 669 int retval; 670 671 if ((jp->flags & JPIPEFAIL) && jp->nprocs) { 672 int i; 673 674 for (i = 0; i < jp->nprocs; i++) 675 if (jp->ps[i].status != 0) 676 status = jp->ps[i].status; 677 } else 678 status = jp->ps[jp->nprocs ? jp->nprocs - 1 : 0].status; 679 680 if (raw) 681 return status; 682 683 if (WIFEXITED(status)) 684 retval = WEXITSTATUS(status); 685 #if JOBS 686 else if (WIFSTOPPED(status)) 687 retval = WSTOPSIG(status) + 128; 688 #endif 689 else { 690 /* XXX: limits number of signals */ 691 retval = WTERMSIG(status) + 128; 692 } 693 694 return retval; 695 } 696 697 698 699 int 700 waitcmd(int argc, char **argv) 701 { 702 struct job *job, *last; 703 int retval; 704 struct job *jp; 705 int i; 706 int any = 0; 707 int found; 708 int oldwait = 0; 709 char *pid = NULL, *fpid; 710 char **arg; 711 char idstring[20]; 712 713 while ((i = nextopt("np:")) != '\0') { 714 switch (i) { 715 case 'n': 716 any = 1; 717 break; 718 case 'p': 719 if (pid) 720 error("more than one -p unsupported"); 721 pid = optionarg; 722 break; 723 } 724 } 725 726 if (!any && *argptr == 0) 727 oldwait = 1; 728 729 if (pid != NULL) { 730 if (!validname(pid, '\0', NULL)) 731 error("invalid name: -p '%s'", pid); 732 if (unsetvar(pid, 0)) 733 error("%s readonly", pid); 734 } 735 736 /* 737 * If we have forked, and not yet created any new jobs, then 738 * we have no children, whatever jobtab claims, 739 * so simply return in that case. 740 * 741 * The return code is 127 if we had any pid args (none are found) 742 * or if we had -n (nothing exited), but 0 for plain old "wait". 743 */ 744 if (jobs_invalid) { 745 CTRACE(DBG_WAIT, ("builtin wait%s%s in child, invalid jobtab\n", 746 any ? " -n" : "", *argptr ? " pid..." : "")); 747 return oldwait ? 0 : 127; 748 } 749 750 /* 751 * clear stray flags left from previous waitcmd 752 * or set them instead if anything will do ("wait -n") 753 */ 754 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 755 if (any && *argptr == NULL) 756 jp->flags |= JOBWANTED; 757 else 758 jp->flags &= ~JOBWANTED; 759 jp->ref = NULL; 760 } 761 762 CTRACE(DBG_WAIT, 763 ("builtin wait%s%s\n", any ? " -n" : "", *argptr ? " pid..." : "")); 764 765 /* 766 * First, validate the jobnum args, count how many refer to 767 * (different) running jobs, and if we had -n, and found that one has 768 * already finished, we return that one. Otherwise remember 769 * which ones we are looking for (JOBWANTED). 770 */ 771 found = 0; 772 last = NULL; 773 for (arg = argptr; *arg; arg++) { 774 last = jp = getjob(*arg, 1); 775 if (!jp) 776 continue; 777 if (jp->ref == NULL) 778 jp->ref = *arg; 779 if (any && jp->state == JOBDONE) { 780 /* 781 * We just want any of them, and this one is 782 * ready for consumption, bon apetit ... 783 */ 784 retval = jobstatus(jp, 0); 785 if (pid) 786 setvar(pid, *arg, 0); 787 if (!iflag) 788 freejob(jp); 789 CTRACE(DBG_WAIT, ("wait -n found %s already done: %d\n", *arg, retval)); 790 return retval; 791 } 792 if (!(jp->flags & JOBWANTED)) { 793 /* 794 * It is possible to list the same job several 795 * times - the obvious "wait 1 1 1" or 796 * "wait %% %2 102" where job 2 is current and pid 102 797 * However many times it is requested, it is found once. 798 */ 799 found++; 800 jp->flags |= JOBWANTED; 801 } 802 job = jp; 803 } 804 805 VTRACE(DBG_WAIT, ("wait %s%s%sfound %d candidates (last %s)\n", 806 any ? "-n " : "", *argptr ? *argptr : "", 807 argptr[0] && argptr[1] ? "... " : " ", found, 808 job && job->used ? (job->ref ? job->ref : "<no-arg>") : "none")); 809 810 /* 811 * If we were given a list of jobnums: 812 * and none of those exist, then we're done. 813 */ 814 if (*argptr && found == 0) 815 return 127; 816 817 /* 818 * Otherwise we need to wait for something to complete 819 * When it does, we check and see if it is one of the 820 * jobs we're waiting on, and if so, we clean it up. 821 * If we had -n, then we're done, otherwise we do it all again 822 * until all we had listed are done, of if there were no 823 * jobnum args, all are done. 824 */ 825 826 retval = any || *argptr ? 127 : 0; 827 fpid = NULL; 828 for (;;) { 829 VTRACE(DBG_WAIT, ("wait waiting (%d remain): ", found)); 830 job = NULL; 831 for (jp = jobtab, i = njobs; --i >= 0; jp++) { 832 if (jp->used && jp->flags & JOBWANTED && 833 jp->state == JOBDONE) { 834 job = jp; 835 break; 836 } 837 if (jp->used && jp->state == JOBRUNNING) 838 job = jp; 839 } 840 if (i < 0 && job == NULL) { 841 CTRACE(DBG_WAIT, ("nothing running (ret: %d) fpid %s\n", 842 retval, fpid ? fpid : "unset")); 843 if (pid && fpid) 844 setvar(pid, fpid, 0); 845 return retval; 846 } 847 jp = job; 848 VTRACE(DBG_WAIT, ("found @%d/%d state: %d\n", njobs-i, njobs, 849 jp->state)); 850 851 /* 852 * There is at least 1 job running, so we can 853 * safely wait() (blocking) for something to exit. 854 */ 855 if (jp->state == JOBRUNNING) { 856 job = NULL; 857 if ((i = dowait(WBLOCK|WNOFREE, NULL, &job)) == -1) 858 return 128 + lastsig(); 859 860 /* 861 * This happens if an interloper has died 862 * (eg: a child of the executable that exec'd us) 863 * Simply go back and start all over again 864 * (this is rare). 865 */ 866 if (job == NULL) 867 continue; 868 869 /* 870 * one of the reported job's processes exited, 871 * but there are more still running, back for more 872 */ 873 if (job->state == JOBRUNNING) 874 continue; 875 } else 876 job = jp; /* we want this, and it is done */ 877 878 if (job->flags & JOBWANTED) { 879 int rv; 880 881 job->flags &= ~JOBWANTED; /* got it */ 882 rv = jobstatus(job, 0); 883 VTRACE(DBG_WAIT, ( 884 "wanted %d (%s) done: st=%d", i, 885 job->ref ? job->ref : "", rv)); 886 if (any || job == last) { 887 retval = rv; 888 fpid = job->ref; 889 890 VTRACE(DBG_WAIT, (" save")); 891 if (pid) { 892 /* 893 * don't need fpid unless we are going 894 * to return it. 895 */ 896 if (fpid == NULL) { 897 /* 898 * this only happens with "wait -n" 899 * (that is, no pid args) 900 */ 901 snprintf(idstring, sizeof idstring, 902 "%d", job->ps[ job->nprocs ? 903 job->nprocs-1 : 0 ].pid); 904 fpid = idstring; 905 } 906 VTRACE(DBG_WAIT, (" (for %s)", fpid)); 907 } 908 } 909 910 if (job->state == JOBDONE) { 911 VTRACE(DBG_WAIT, (" free")); 912 freejob(job); 913 } 914 915 if (any || (found > 0 && --found == 0)) { 916 if (pid && fpid) 917 setvar(pid, fpid, 0); 918 VTRACE(DBG_WAIT, (" return %d\n", retval)); 919 return retval; 920 } 921 VTRACE(DBG_WAIT, ("\n")); 922 continue; 923 } 924 925 /* this is to handle "wait" (no args) */ 926 if (oldwait && job->state == JOBDONE) { 927 VTRACE(DBG_JOBS|DBG_WAIT, ("Cleanup: %d\n", i)); 928 freejob(job); 929 } 930 } 931 } 932 933 934 int 935 jobidcmd(int argc, char **argv) 936 { 937 struct job *jp; 938 int i; 939 int pg = 0, onep = 0, job = 0; 940 941 while ((i = nextopt("gjp"))) { 942 switch (i) { 943 case 'g': pg = 1; break; 944 case 'j': job = 1; break; 945 case 'p': onep = 1; break; 946 } 947 } 948 CTRACE(DBG_JOBS, ("jobidcmd%s%s%s%s %s\n", pg ? " -g" : "", 949 onep ? " -p" : "", job ? " -j" : "", jobs_invalid ? " [inv]" : "", 950 *argptr ? *argptr : "<implicit %%>")); 951 if (pg + onep + job > 1) 952 error("-g -j and -p options cannot be combined"); 953 954 if (argptr[0] && argptr[1]) 955 error("usage: jobid [-g|-p|-r] jobid"); 956 957 jp = getjob(*argptr, 0); 958 if (job) { 959 out1fmt("%%%d\n", JNUM(jp)); 960 return 0; 961 } 962 if (pg) { 963 if (jp->pgrp != 0) { 964 out1fmt("%ld\n", (long)jp->pgrp); 965 return 0; 966 } 967 return 1; 968 } 969 if (onep) { 970 i = jp->nprocs - 1; 971 if (i < 0) 972 return 1; 973 out1fmt("%ld\n", (long)jp->ps[i].pid); 974 return 0; 975 } 976 for (i = 0 ; i < jp->nprocs ; ) { 977 out1fmt("%ld", (long)jp->ps[i].pid); 978 out1c(++i < jp->nprocs ? ' ' : '\n'); 979 } 980 return 0; 981 } 982 983 #if JOBS 984 #ifndef SMALL 985 986 static int 987 stop_me(int sig, int force, int pgrp, pid_t pid) 988 { 989 if (force || (!loginsh && mflag && rootshell)) { 990 struct sigaction sig_dfl, sig_was; 991 992 sig_dfl.sa_handler = SIG_DFL; 993 sig_dfl.sa_flags = 0; 994 sigemptyset(&sig_dfl.sa_mask); 995 996 (void)sigaction(sig, &sig_dfl, &sig_was); 997 998 if (kill(pgrp ? 0 : pid, sig) == -1) { 999 sh_warn("suspend myself"); 1000 (void)sigaction(sig, &sig_was, NULL); 1001 error(NULL); 1002 } 1003 1004 (void)sigaction(sig, &sig_was, NULL); 1005 1006 return 0; 1007 } 1008 1009 if (!rootshell) 1010 sh_warnx("subshell environment"); 1011 else if (!mflag) 1012 sh_warnx("job control disabled"); 1013 else if (loginsh) 1014 sh_warnx("login shell"); 1015 else 1016 sh_warnx("not possible??"); 1017 1018 return 1; 1019 } 1020 1021 int 1022 suspendcmd(int argc, char **argv) 1023 { 1024 int sig = SIGTSTP; 1025 int force = 0; 1026 int pgrp = 0; 1027 int status = 0; 1028 char *target; 1029 int c; 1030 1031 while ((c = nextopt("fgs:")) != 0) { 1032 switch (c) { 1033 case 'f': 1034 force = 1; 1035 break; 1036 case 'g': 1037 pgrp = 1; 1038 break; 1039 case 's': 1040 sig = signame_to_signum(optionarg); 1041 1042 if (sig != SIGSTOP && sig != SIGTSTP && 1043 sig != SIGTTIN && sig != SIGTTOU) 1044 error("bad signal '%s'", optionarg); 1045 break; 1046 } 1047 } 1048 1049 if (!*argptr) /* suspend myself */ 1050 return stop_me(sig, force, pgrp, getpid()); 1051 1052 while ((target = *argptr++) != NULL) 1053 { 1054 int pid; 1055 1056 if (is_number(target)) { 1057 if ((pid = number(target)) == 0) { 1058 sh_warnx("Cannot (yet) suspend kernel (%s)", 1059 target); 1060 status = 1; 1061 continue; 1062 } 1063 } else if ((pid = getjobpgrp(target)) == 0) { 1064 sh_warnx("Unknown job: %s", target); 1065 status = 1; 1066 continue; 1067 } 1068 1069 if (pid == rootpid || pid == getpid()) { 1070 status |= stop_me(sig, force, pgrp, pid); 1071 continue; 1072 } 1073 1074 if (pid == 1 || pid == -1) { 1075 sh_warnx("Don't be funny"); 1076 status = 1; 1077 continue; 1078 } 1079 1080 if (pid > 0 && pgrp) 1081 pid = -pid; 1082 1083 if (kill(pid, sig) == -1) { 1084 sh_warn("failed to suspend %s", target); 1085 status = 1; 1086 } 1087 } 1088 1089 return status; 1090 } 1091 #endif /* SMALL */ 1092 #endif /* JOBS */ 1093 1094 int 1095 getjobpgrp(const char *name) 1096 { 1097 struct job *jp; 1098 1099 if (jobs_invalid) 1100 return 0; 1101 jp = getjob(name, 1); 1102 if (jp == 0) 1103 return 0; 1104 return -jp->pgrp; 1105 } 1106 1107 /* 1108 * Convert a job name to a job structure. 1109 */ 1110 1111 STATIC struct job * 1112 getjob(const char *name, int noerror) 1113 { 1114 int jobno = -1; 1115 struct job *jp; 1116 int pid; 1117 int i; 1118 const char *err_msg = "No such job: %s"; 1119 1120 if (name == NULL) { 1121 #if JOBS 1122 jobno = curjob; 1123 #endif 1124 err_msg = "No current job"; 1125 } else if (name[0] == '%') { 1126 if (is_number(name + 1)) { 1127 jobno = number(name + 1) - 1; 1128 } else if (!name[1] || !name[2]) { 1129 switch (name[1]) { 1130 #if JOBS 1131 case 0: 1132 case '+': 1133 case '%': 1134 jobno = curjob; 1135 err_msg = "No current job"; 1136 break; 1137 case '-': 1138 jobno = curjob; 1139 if (jobno != -1) 1140 jobno = jobtab[jobno].prev_job; 1141 err_msg = "No previous job"; 1142 break; 1143 #endif 1144 default: 1145 goto check_pattern; 1146 } 1147 } else { 1148 struct job *found; 1149 check_pattern: 1150 found = NULL; 1151 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 1152 if (!jp->used || jp->nprocs <= 0) 1153 continue; 1154 if ((name[1] == '?' 1155 && strstr(jp->ps[0].cmd, name + 2)) 1156 || prefix(name + 1, jp->ps[0].cmd)) { 1157 if (found) { 1158 err_msg = "%s: ambiguous"; 1159 found = 0; 1160 break; 1161 } 1162 found = jp; 1163 } 1164 } 1165 if (found) 1166 return found; 1167 } 1168 1169 } else if (is_number(name)) { 1170 pid = number(name); 1171 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 1172 if (jp->used && jp->nprocs > 0 1173 && jp->ps[jp->nprocs - 1].pid == pid) 1174 return jp; 1175 } 1176 } 1177 1178 if (jobno >= 0 && jobno < njobs) { 1179 jp = jobtab + jobno; 1180 if (jp->used) 1181 return jp; 1182 } 1183 if (!noerror) 1184 error(err_msg, name); 1185 return 0; 1186 } 1187 1188 1189 /* 1190 * Find out if there are any running (that is, unwaited upon) 1191 * background children of the current shell. 1192 * 1193 * Return 1/0 (yes, no). 1194 * 1195 * Needed as we cannot optimise away sub-shell creation if 1196 * we have such a child, or a "wait" in that sub-shell would 1197 * observe the already existing job. 1198 */ 1199 int 1200 anyjobs(void) 1201 { 1202 struct job *jp; 1203 int i; 1204 1205 if (jobs_invalid) 1206 return 0; 1207 1208 for (i = njobs, jp = jobtab ; --i >= 0 ; jp++) { 1209 if (jp->used) 1210 return 1; 1211 } 1212 1213 return 0; 1214 } 1215 1216 /* 1217 * Output the (new) POSIX required "[%d] %d" string whenever an 1218 * async (ie: background) job is started in an interactive shell. 1219 * Note that a subshell environment is not regarded as interactive. 1220 */ 1221 void 1222 jobstarted(struct job *jp) 1223 { 1224 if (!iflag || !rootshell) 1225 return; 1226 1227 outfmt(out2, "[%d] %ld\n", JNUM(jp), 1228 jp->pgrp != 0 ? (long)jp->pgrp : (long)jp->ps->pid); 1229 } 1230 1231 /* 1232 * Return a new job structure, 1233 */ 1234 1235 struct job * 1236 makejob(union node *node, int nprocs) 1237 { 1238 int i; 1239 struct job *jp; 1240 1241 if (jobs_invalid) { 1242 VTRACE(DBG_JOBS, ("makejob(%p, %d) clearing jobtab (%d)\n", 1243 (void *)node, nprocs, njobs)); 1244 for (i = njobs, jp = jobtab ; --i >= 0 ; jp++) { 1245 if (jp->used) 1246 freejob(jp); 1247 } 1248 jobs_invalid = 0; 1249 } 1250 1251 for (i = njobs, jp = jobtab ; ; jp++) { 1252 if (--i < 0) { 1253 INTOFF; 1254 if (njobs == 0) { 1255 jobtab = ckmalloc(4 * sizeof jobtab[0]); 1256 } else { 1257 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 1258 memcpy(jp, jobtab, njobs * sizeof jp[0]); 1259 /* Relocate `ps' pointers */ 1260 for (i = 0; i < njobs; i++) 1261 if (jp[i].ps == &jobtab[i].ps0) 1262 jp[i].ps = &jp[i].ps0; 1263 ckfree(jobtab); 1264 jobtab = jp; 1265 } 1266 jp = jobtab + njobs; 1267 for (i = 4 ; --i >= 0 ; njobs++) { 1268 jobtab[njobs].used = 0; 1269 jobtab[njobs].prev_job = -1; 1270 } 1271 INTON; 1272 break; 1273 } 1274 if (jp->used == 0) 1275 break; 1276 } 1277 INTOFF; 1278 jp->state = JOBRUNNING; 1279 jp->used = 1; 1280 jp->flags = pipefail ? JPIPEFAIL : 0; 1281 jp->nprocs = 0; 1282 jp->pgrp = 0; 1283 #if JOBS 1284 jp->jobctl = jobctl; 1285 set_curjob(jp, 1); 1286 #endif 1287 if (nprocs > 1) { 1288 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 1289 } else { 1290 jp->ps = &jp->ps0; 1291 } 1292 INTON; 1293 VTRACE(DBG_JOBS, ("makejob(%p, %d)%s returns %%%d\n", (void *)node, 1294 nprocs, (jp->flags & JPIPEFAIL) ? " PF" : "", JNUM(jp))); 1295 return jp; 1296 } 1297 1298 1299 /* 1300 * Fork off a subshell. If we are doing job control, give the subshell its 1301 * own process group. Jp is a job structure that the job is to be added to. 1302 * N is the command that will be evaluated by the child. Both jp and n may 1303 * be NULL. The mode parameter can be one of the following: 1304 * FORK_FG - Fork off a foreground process. 1305 * FORK_BG - Fork off a background process. 1306 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 1307 * process group even if job control is on. 1308 * 1309 * When job control is turned off, background processes have their standard 1310 * input redirected to /dev/null (except for the second and later processes 1311 * in a pipeline). 1312 */ 1313 1314 int 1315 forkshell(struct job *jp, union node *n, int mode) 1316 { 1317 pid_t pid; 1318 int serrno; 1319 1320 CTRACE(DBG_JOBS, ("forkshell(%%%d, %p, %d) called\n", 1321 JNUM(jp), n, mode)); 1322 1323 switch ((pid = fork())) { 1324 case -1: 1325 serrno = errno; 1326 VTRACE(DBG_JOBS, ("Fork failed, errno=%d\n", serrno)); 1327 error("Cannot fork (%s)", strerror(serrno)); 1328 break; 1329 case 0: 1330 SHELL_FORKED(); 1331 forkchild(jp, n, mode, 0); 1332 return 0; 1333 default: 1334 return forkparent(jp, n, mode, pid); 1335 } 1336 } 1337 1338 int 1339 forkparent(struct job *jp, union node *n, int mode, pid_t pid) 1340 { 1341 int pgrp = 0; 1342 1343 if (rootshell && mode != FORK_NOJOB && mflag) { 1344 /* 1345 * The process group ID must always be that of the 1346 * first process created for the job. If this proc 1347 * is the first, that's us, otherwise the pgrp has 1348 * already been determined. 1349 */ 1350 if (jp == NULL || jp->nprocs == 0) 1351 pgrp = pid; 1352 else 1353 pgrp = jp->pgrp; 1354 /* This can fail because we are doing it in the child also */ 1355 (void)setpgid(pid, pgrp); 1356 } 1357 if (mode == FORK_BG) 1358 backgndpid = pid; /* set $! */ 1359 if (jp) { 1360 struct procstat *ps = &jp->ps[jp->nprocs++]; 1361 ps->pid = pid; 1362 ps->status = -1; 1363 ps->cmd[0] = 0; 1364 jp->pgrp = pgrp; /* 0 if !mflag */ 1365 if (/* iflag && rootshell && */ n) 1366 commandtext(ps, n); 1367 } 1368 CTRACE(DBG_JOBS, ("In parent shell: child = %d (mode %d)\n",pid,mode)); 1369 return pid; 1370 } 1371 1372 void 1373 forkchild(struct job *jp, union node *n, int mode, int vforked) 1374 { 1375 int wasroot; 1376 int pgrp; 1377 const char *devnull = _PATH_DEVNULL; 1378 const char *nullerr = "Can't open %s"; 1379 1380 wasroot = rootshell; 1381 CTRACE(DBG_JOBS, ("Child shell %d %sforked from %d (mode %d)\n", 1382 getpid(), vforked?"v":"", getppid(), mode)); 1383 1384 if (!vforked) { 1385 rootshell = 0; 1386 handler = &main_handler; 1387 } 1388 1389 closescript(vforked); 1390 clear_traps(vforked); 1391 #if JOBS 1392 if (!vforked) 1393 jobctl = 0; /* do job control only in root shell */ 1394 if (wasroot && mode != FORK_NOJOB && mflag) { 1395 if (jp == NULL || jp->nprocs == 0) 1396 pgrp = getpid(); 1397 else 1398 pgrp = jp->ps[0].pid; 1399 /* This can fail because we are doing it in the parent also */ 1400 (void)setpgid(0, pgrp); 1401 if (mode == FORK_FG) { 1402 if (tcsetpgrp(ttyfd, pgrp) == -1) 1403 error("Cannot set tty process group (%s) at %d", 1404 strerror(errno), __LINE__); 1405 } 1406 setsignal(SIGTSTP, vforked); 1407 setsignal(SIGTTOU, vforked); 1408 } else if (mode == FORK_BG) { 1409 ignoresig(SIGINT, vforked); 1410 ignoresig(SIGQUIT, vforked); 1411 if ((jp == NULL || jp->nprocs == 0) && 1412 ! fd0_redirected_p ()) { 1413 close(0); 1414 if (open(devnull, O_RDONLY) != 0) 1415 error(nullerr, devnull); 1416 } 1417 } 1418 #else 1419 if (mode == FORK_BG) { 1420 ignoresig(SIGINT, vforked); 1421 ignoresig(SIGQUIT, vforked); 1422 if ((jp == NULL || jp->nprocs == 0) && 1423 ! fd0_redirected_p ()) { 1424 close(0); 1425 if (open(devnull, O_RDONLY) != 0) 1426 error(nullerr, devnull); 1427 } 1428 } 1429 #endif 1430 if (wasroot && iflag) { 1431 setsignal(SIGINT, vforked); 1432 setsignal(SIGQUIT, vforked); 1433 setsignal(SIGTERM, vforked); 1434 } 1435 1436 if (!vforked) 1437 jobs_invalid = 1; 1438 } 1439 1440 /* 1441 * Wait for job to finish. 1442 * 1443 * Under job control we have the problem that while a child process is 1444 * running interrupts generated by the user are sent to the child but not 1445 * to the shell. This means that an infinite loop started by an inter- 1446 * active user may be hard to kill. With job control turned off, an 1447 * interactive user may place an interactive program inside a loop. If 1448 * the interactive program catches interrupts, the user doesn't want 1449 * these interrupts to also abort the loop. The approach we take here 1450 * is to have the shell ignore interrupt signals while waiting for a 1451 * foreground process to terminate, and then send itself an interrupt 1452 * signal if the child process was terminated by an interrupt signal. 1453 * Unfortunately, some programs want to do a bit of cleanup and then 1454 * exit on interrupt; unless these processes terminate themselves by 1455 * sending a signal to themselves (instead of calling exit) they will 1456 * confuse this approach. 1457 */ 1458 1459 int 1460 waitforjob(struct job *jp) 1461 { 1462 #if JOBS 1463 int mypgrp = getpgrp(); 1464 #endif 1465 int status; 1466 int st; 1467 1468 INTOFF; 1469 VTRACE(DBG_JOBS, ("waitforjob(%%%d) called\n", JNUM(jp))); 1470 while (jp->state == JOBRUNNING) { 1471 dowait(WBLOCK, jp, NULL); 1472 } 1473 #if JOBS 1474 if (jp->jobctl) { 1475 if (tcsetpgrp(ttyfd, mypgrp) == -1) 1476 error("Cannot set tty process group (%s) at %d", 1477 strerror(errno), __LINE__); 1478 } 1479 if (jp->state == JOBSTOPPED && curjob != jp - jobtab) 1480 set_curjob(jp, 2); 1481 #endif 1482 status = jobstatus(jp, 1); 1483 1484 /* convert to 8 bits */ 1485 if (WIFEXITED(status)) 1486 st = WEXITSTATUS(status); 1487 #if JOBS 1488 else if (WIFSTOPPED(status)) 1489 st = WSTOPSIG(status) + 128; 1490 #endif 1491 else 1492 st = WTERMSIG(status) + 128; 1493 1494 VTRACE(DBG_JOBS, ("waitforjob: job %d, nproc %d, status %d, st %x\n", 1495 JNUM(jp), jp->nprocs, status, st)); 1496 #if JOBS 1497 if (jp->jobctl) { 1498 /* 1499 * This is truly gross. 1500 * If we're doing job control, then we did a TIOCSPGRP which 1501 * caused us (the shell) to no longer be in the controlling 1502 * session -- so we wouldn't have seen any ^C/SIGINT. So, we 1503 * intuit from the subprocess exit status whether a SIGINT 1504 * occurred, and if so interrupt ourselves. Yuck. - mycroft 1505 */ 1506 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 1507 raise(SIGINT); 1508 } 1509 #endif 1510 if (! JOBS || jp->state == JOBDONE) 1511 freejob(jp); 1512 INTON; 1513 return st; 1514 } 1515 1516 1517 1518 /* 1519 * Wait for a process (any process) to terminate. 1520 * 1521 * If "job" is given (not NULL), then its jobcontrol status (and mflag) 1522 * are used to determine if we wait for stopping/continuing processes or 1523 * only terminating ones, and the decision whether to report to stdout 1524 * or not varies depending what happened, and whether the affected job 1525 * is the one that was requested or not. 1526 * 1527 * If "changed" is not NULL, then the job which changed because a 1528 * process terminated/stopped will be reported by setting *changed, 1529 * if there is any such job, otherwise we set *changed = NULL. 1530 */ 1531 1532 STATIC int 1533 dowait(int flags, struct job *job, struct job **changed) 1534 { 1535 int pid; 1536 int status; 1537 struct procstat *sp; 1538 struct job *jp; 1539 struct job *thisjob; 1540 int done; 1541 int stopped; 1542 int err; 1543 1544 VTRACE(DBG_JOBS|DBG_PROCS, ("dowait(%x) called for job %d%s\n", 1545 flags, JNUM(job), changed ? " [report change]" : "")); 1546 1547 if (changed != NULL) 1548 *changed = NULL; 1549 1550 /* 1551 * First deal with the kernel, collect info on any (one) of our 1552 * children that has changed state since we last asked. 1553 * (loop if we're interrupted by a signal that we aren't processing) 1554 */ 1555 do { 1556 err = 0; 1557 pid = waitproc(flags & WBLOCK, job, &status); 1558 if (pid == -1) 1559 err = errno; 1560 VTRACE(DBG_JOBS|DBG_PROCS, 1561 ("wait returns pid %d (e:%d), status %#x (ps=%d)\n", 1562 pid, err, status, pendingsigs)); 1563 } while (pid == -1 && err == EINTR && pendingsigs == 0); 1564 1565 /* 1566 * if nothing exited/stopped/..., we have nothing else to do 1567 */ 1568 if (pid <= 0) 1569 return pid; 1570 1571 /* 1572 * Otherwise, try to find the process, somewhere in our job table 1573 */ 1574 INTOFF; 1575 thisjob = NULL; 1576 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1577 if (jp->used) { 1578 /* 1579 * For each job that is in use (this is one) 1580 */ 1581 done = 1; /* assume it is finished */ 1582 stopped = 1; /* and has stopped */ 1583 1584 /* 1585 * Now scan all our child processes of the job 1586 */ 1587 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1588 if (sp->pid == -1) 1589 continue; 1590 /* 1591 * If the process that changed is the one 1592 * we're looking at, and it was previously 1593 * running (-1) or was stopped (anything else 1594 * and it must have already finished earlier, 1595 * so cannot be the process that just changed) 1596 * then we update its status 1597 */ 1598 if (sp->pid == pid && 1599 (sp->status==-1 || WIFSTOPPED(sp->status))) { 1600 VTRACE(DBG_JOBS | DBG_PROCS, 1601 ("Job %d: changing status of proc %d from %#x to ", 1602 JNUM(jp), pid, sp->status)); 1603 1604 /* 1605 * If the process continued, 1606 * then update its status to running 1607 * and mark the job running as well. 1608 * 1609 * If it was anything but running 1610 * before, flag it as a change for 1611 * reporting purposes later 1612 */ 1613 if (WIFCONTINUED(status)) { 1614 if (sp->status != -1) 1615 jp->flags |= JOBCHANGED; 1616 sp->status = -1; 1617 jp->state = JOBRUNNING; 1618 VTRACE(DBG_JOBS|DBG_PROCS, 1619 ("running\n")); 1620 } else { 1621 /* otherwise update status */ 1622 sp->status = status; 1623 VTRACE(DBG_JOBS|DBG_PROCS, 1624 ("%#x\n", status)); 1625 } 1626 1627 /* 1628 * We now know the affected job 1629 */ 1630 thisjob = jp; 1631 if (changed != NULL) 1632 *changed = jp; 1633 } 1634 /* 1635 * After any update that might have just 1636 * happened, if this process is running, 1637 * the job is not stopped, or if the process 1638 * simply stopped (not terminated) then the 1639 * job is certainly not completed (done). 1640 */ 1641 if (sp->status == -1) 1642 stopped = 0; 1643 else if (WIFSTOPPED(sp->status)) 1644 done = 0; 1645 } 1646 1647 /* 1648 * Once we have examined all processes for the 1649 * job, if we still show it as stopped, then... 1650 */ 1651 if (stopped) { /* stopped or done */ 1652 /* 1653 * it might be stopped, or finished, decide: 1654 */ 1655 int state = done ? JOBDONE : JOBSTOPPED; 1656 1657 /* 1658 * If that wasn't the same as it was before 1659 * then update its state, and if it just 1660 * completed, make it be the current job (%%) 1661 */ 1662 if (jp->state != state) { 1663 VTRACE(DBG_JOBS, 1664 ("Job %d: changing state from %d to %d\n", 1665 JNUM(jp), jp->state, state)); 1666 jp->state = state; 1667 #if JOBS 1668 if (done) 1669 set_curjob(jp, 0); 1670 #endif 1671 } 1672 } 1673 } 1674 } 1675 1676 /* 1677 * Now we have scanned all jobs. If we found the job that 1678 * the process that changed state belonged to (we occasionally 1679 * fork processes without associating them with a job, when one 1680 * of those finishes, we simply ignore it, the zombie has been 1681 * cleaned up, which is all that matters) then we need to 1682 * determine if we should say something about it to stdout 1683 */ 1684 1685 if (thisjob && 1686 (thisjob->state != JOBRUNNING || thisjob->flags & JOBCHANGED)) { 1687 int mode = 0; 1688 1689 if (!rootshell || !iflag) 1690 mode = SHOW_SIGNALLED; 1691 if ((job == thisjob && (flags & WNOFREE) == 0) || 1692 job != thisjob) 1693 mode = SHOW_SIGNALLED | SHOW_NO_FREE; 1694 if (mode && (flags & WSILENT) == 0) 1695 showjob(out2, thisjob, mode); 1696 else { 1697 VTRACE(DBG_JOBS, 1698 ("Not printing status for %p [%d], " 1699 "mode=%#x rootshell=%d, job=%p [%d]\n", 1700 thisjob, JNUM(thisjob), mode, rootshell, 1701 job, JNUM(job))); 1702 thisjob->flags |= JOBCHANGED; 1703 } 1704 } 1705 1706 INTON; 1707 /* 1708 * Finally tell our caller that something happened (in general all 1709 * anyone tests for is <= 0 (or >0) so the actual pid value here 1710 * doesn't matter much, but we know pid is >0 so we may as well 1711 * give back something meaningful 1712 */ 1713 return pid; 1714 } 1715 1716 1717 1718 /* 1719 * Do a wait system call. If job control is compiled in, we accept 1720 * stopped processes. If block is zero, we return a value of zero 1721 * rather than blocking. 1722 * 1723 * System V doesn't have a non-blocking wait system call. It does 1724 * have a SIGCLD signal that is sent to a process when one of its 1725 * children dies. The obvious way to use SIGCLD would be to install 1726 * a handler for SIGCLD which simply bumped a counter when a SIGCLD 1727 * was received, and have waitproc bump another counter when it got 1728 * the status of a process. Waitproc would then know that a wait 1729 * system call would not block if the two counters were different. 1730 * This approach doesn't work because if a process has children that 1731 * have not been waited for, System V will send it a SIGCLD when it 1732 * installs a signal handler for SIGCLD. What this means is that when 1733 * a child exits, the shell will be sent SIGCLD signals continuously 1734 * until is runs out of stack space, unless it does a wait call before 1735 * restoring the signal handler. The code below takes advantage of 1736 * this (mis)feature by installing a signal handler for SIGCLD and 1737 * then checking to see whether it was called. If there are any 1738 * children to be waited for, it will be. 1739 * 1740 * If neither SYSV nor BSD is defined, we don't implement nonblocking 1741 * waits at all. In this case, the user will not be informed when 1742 * a background process ends until the next time she runs a real program 1743 * (as opposed to running a builtin command or just typing return), 1744 * and the jobs command may give out of date information. 1745 */ 1746 1747 #ifdef SYSV 1748 STATIC int gotsigchild; 1749 1750 STATIC int onsigchild() { 1751 gotsigchild = 1; 1752 } 1753 #endif 1754 1755 1756 STATIC int 1757 waitproc(int block, struct job *jp, int *status) 1758 { 1759 #ifdef BSD 1760 int flags = 0; 1761 1762 #if JOBS 1763 if (mflag || (jp != NULL && jp->jobctl)) 1764 flags |= WUNTRACED | WCONTINUED; 1765 #endif 1766 if (block == 0) 1767 flags |= WNOHANG; 1768 VTRACE(DBG_WAIT, ("waitproc: doing waitpid(flags=%#x)\n", flags)); 1769 return waitpid(-1, status, flags); 1770 #else 1771 #ifdef SYSV 1772 int (*save)(); 1773 1774 if (block == 0) { 1775 gotsigchild = 0; 1776 save = signal(SIGCLD, onsigchild); 1777 signal(SIGCLD, save); 1778 if (gotsigchild == 0) 1779 return 0; 1780 } 1781 return wait(status); 1782 #else 1783 if (block == 0) 1784 return 0; 1785 return wait(status); 1786 #endif 1787 #endif 1788 } 1789 1790 /* 1791 * return 1 if there are stopped jobs, otherwise 0 1792 */ 1793 int job_warning = 0; 1794 int 1795 stoppedjobs(void) 1796 { 1797 int jobno; 1798 struct job *jp; 1799 1800 if (job_warning || jobs_invalid) 1801 return (0); 1802 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1803 if (jp->used == 0) 1804 continue; 1805 if (jp->state == JOBSTOPPED) { 1806 out2str("You have stopped jobs.\n"); 1807 job_warning = 2; 1808 return (1); 1809 } 1810 } 1811 1812 return (0); 1813 } 1814 1815 /* 1816 * Return a string identifying a command (to be printed by the 1817 * jobs command). 1818 */ 1819 1820 STATIC char *cmdnextc; 1821 STATIC int cmdnleft; 1822 1823 void 1824 commandtext(struct procstat *ps, union node *n) 1825 { 1826 int len; 1827 1828 cmdnextc = ps->cmd; 1829 if (iflag || mflag || sizeof(ps->cmd) <= 60) 1830 len = sizeof(ps->cmd); 1831 else if (sizeof ps->cmd <= 400) 1832 len = 50; 1833 else if (sizeof ps->cmd <= 800) 1834 len = 80; 1835 else 1836 len = sizeof(ps->cmd) / 10; 1837 cmdnleft = len; 1838 (void)cmdtxt(n, 1); 1839 if (cmdnleft <= 0) { 1840 char *p = ps->cmd + len - 4; 1841 p[0] = '.'; 1842 p[1] = '.'; 1843 p[2] = '.'; 1844 p[3] = 0; 1845 } else 1846 *cmdnextc = '\0'; 1847 1848 VTRACE(DBG_JOBS, 1849 ("commandtext: ps->cmd %p, end %p, left %d\n\t\"%s\"\n", 1850 ps->cmd, cmdnextc, cmdnleft, ps->cmd)); 1851 } 1852 1853 1854 /* 1855 * Generate a string describing tree node n & its descendants (recursive calls) 1856 * 1857 * Return true (non-zero) if the output is complete (ends with an operator) 1858 * so no ';' need be added before the following command. Return false (zero) 1859 * if a ';' is needed to terminate the output if it is followed by something 1860 * which is not an operator. 1861 */ 1862 STATIC int 1863 cmdtxt(union node *n, int top) 1864 { 1865 union node *np; 1866 struct nodelist *lp; 1867 const char *p; 1868 int i; 1869 1870 if (n == NULL || cmdnleft <= 0) 1871 return 1; 1872 switch (n->type) { 1873 case NSEMI: 1874 if (!cmdtxt(n->nbinary.ch1, 0)) 1875 cmdputs(";"); 1876 cmdputs(" "); 1877 return cmdtxt(n->nbinary.ch2, 0); 1878 case NAND: 1879 (void)cmdtxt(n->nbinary.ch1, 0); 1880 cmdputs(" && "); 1881 return cmdtxt(n->nbinary.ch2, 0); 1882 case NOR: 1883 (void) cmdtxt(n->nbinary.ch1, 0); 1884 cmdputs(" || "); 1885 return cmdtxt(n->nbinary.ch2, 0); 1886 case NDNOT: 1887 cmdputs("! "); 1888 /* FALLTHROUGH */ 1889 case NNOT: 1890 cmdputs("! "); 1891 return cmdtxt(n->nnot.com, 0); 1892 break; 1893 case NPIPE: 1894 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1895 (void) cmdtxt(lp->n, 0); 1896 if (lp->next) 1897 cmdputs(" | "); 1898 } 1899 if (!top && n->npipe.backgnd) { 1900 cmdputs(" &"); 1901 return 1; 1902 } 1903 return 0; 1904 case NSUBSHELL: 1905 cmdputs("("); 1906 (void) cmdtxt(n->nredir.n, 0); 1907 cmdputs(")"); 1908 return 0; 1909 case NREDIR: 1910 case NBACKGND: 1911 return cmdtxt(n->nredir.n, top); 1912 case NIF: 1913 cmdputs("if "); 1914 if (!cmdtxt(n->nif.test, 0)) 1915 cmdputs(";"); 1916 cmdputs(" then "); 1917 i = cmdtxt(n->nif.ifpart, 0); 1918 if (n->nif.elsepart) { 1919 if (i == 0) 1920 cmdputs(";"); 1921 cmdputs(" else "); 1922 i = cmdtxt(n->nif.elsepart, 0); 1923 } 1924 if (i == 0) 1925 cmdputs(";"); 1926 cmdputs(" fi"); 1927 return 0; 1928 case NWHILE: 1929 cmdputs("while "); 1930 goto until; 1931 case NUNTIL: 1932 cmdputs("until "); 1933 until: 1934 if (!cmdtxt(n->nbinary.ch1, 0)) 1935 cmdputs(";"); 1936 cmdputs(" do "); 1937 if (!cmdtxt(n->nbinary.ch2, 0)) 1938 cmdputs(";"); 1939 cmdputs(" done"); 1940 return 0; 1941 case NFOR: 1942 cmdputs("for "); 1943 cmdputs(n->nfor.var); 1944 cmdputs(" in "); 1945 cmdlist(n->nfor.args, 1); 1946 cmdputs("; do "); 1947 if (!cmdtxt(n->nfor.body, 0)) 1948 cmdputs(";"); 1949 cmdputs(" done"); 1950 return 0; 1951 case NCASE: 1952 cmdputs("case "); 1953 cmdputs(n->ncase.expr->narg.text); 1954 cmdputs(" in "); 1955 for (np = n->ncase.cases; np; np = np->nclist.next) { 1956 (void) cmdtxt(np->nclist.pattern, 0); 1957 cmdputs(") "); 1958 (void) cmdtxt(np->nclist.body, 0); 1959 switch (n->type) { /* switch (not if) for later */ 1960 case NCLISTCONT: 1961 cmdputs(" ;& "); 1962 break; 1963 default: 1964 cmdputs(" ;; "); 1965 break; 1966 } 1967 } 1968 cmdputs("esac"); 1969 return 0; 1970 case NDEFUN: 1971 cmdputs(n->narg.text); 1972 cmdputs("() { ... }"); 1973 return 0; 1974 case NCMD: 1975 cmdlist(n->ncmd.args, 1); 1976 cmdlist(n->ncmd.redirect, 0); 1977 if (!top && n->ncmd.backgnd) { 1978 cmdputs(" &"); 1979 return 1; 1980 } 1981 return 0; 1982 case NARG: 1983 cmdputs(n->narg.text); 1984 return 0; 1985 case NTO: 1986 p = ">"; i = 1; goto redir; 1987 case NCLOBBER: 1988 p = ">|"; i = 1; goto redir; 1989 case NAPPEND: 1990 p = ">>"; i = 1; goto redir; 1991 case NTOFD: 1992 p = ">&"; i = 1; goto redir; 1993 case NFROM: 1994 p = "<"; i = 0; goto redir; 1995 case NFROMFD: 1996 p = "<&"; i = 0; goto redir; 1997 case NFROMTO: 1998 p = "<>"; i = 0; goto redir; 1999 redir: 2000 if (n->nfile.fd != i) 2001 cmdputi(n->nfile.fd); 2002 cmdputs(p); 2003 if (n->type == NTOFD || n->type == NFROMFD) { 2004 if (n->ndup.dupfd < 0) 2005 cmdputs("-"); 2006 else 2007 cmdputi(n->ndup.dupfd); 2008 } else { 2009 (void) cmdtxt(n->nfile.fname, 0); 2010 } 2011 return 0; 2012 case NHERE: 2013 case NXHERE: 2014 cmdputs("<<..."); 2015 return 0; 2016 default: 2017 cmdputs("???"); 2018 return 0; 2019 } 2020 return 0; 2021 } 2022 2023 STATIC void 2024 cmdlist(union node *np, int sep) 2025 { 2026 for (; np; np = np->narg.next) { 2027 if (!sep) 2028 cmdputs(" "); 2029 (void) cmdtxt(np, 0); 2030 if (sep && np->narg.next) 2031 cmdputs(" "); 2032 } 2033 } 2034 2035 2036 STATIC void 2037 cmdputs(const char *s) 2038 { 2039 const char *p, *str = 0; 2040 char c, cc[2] = " "; 2041 char *nextc; 2042 int nleft; 2043 int subtype = 0; 2044 int quoted = 0; 2045 static char vstype[16][4] = { "", "}", "-", "+", "?", "=", 2046 "#", "##", "%", "%%", "}" }; 2047 2048 p = s; 2049 nextc = cmdnextc; 2050 nleft = cmdnleft; 2051 while (nleft > 0 && (c = *p++) != 0) { 2052 switch (c) { 2053 case CTLNONL: 2054 c = '\0'; 2055 break; 2056 case CTLESC: 2057 c = *p++; 2058 break; 2059 case CTLVAR: 2060 subtype = *p++; 2061 if (subtype & VSLINENO) { /* undo LINENO hack */ 2062 if ((subtype & VSTYPE) == VSLENGTH) 2063 str = "${#LINENO"; /*}*/ 2064 else 2065 str = "${LINENO"; /*}*/ 2066 while (is_digit(*p)) 2067 p++; 2068 } else if ((subtype & VSTYPE) == VSLENGTH) 2069 str = "${#"; /*}*/ 2070 else 2071 str = "${"; /*}*/ 2072 if (!(subtype & VSQUOTE) != !(quoted & 1)) { 2073 quoted ^= 1; 2074 c = '"'; 2075 } else { 2076 c = *str++; 2077 } 2078 break; 2079 case CTLENDVAR: /*{*/ 2080 c = '}'; 2081 if (quoted & 1) 2082 str = "\""; 2083 quoted >>= 1; 2084 subtype = 0; 2085 break; 2086 case CTLBACKQ: 2087 c = '$'; 2088 str = "(...)"; 2089 break; 2090 case CTLBACKQ+CTLQUOTE: 2091 c = '"'; 2092 str = "$(...)\""; 2093 break; 2094 case CTLARI: 2095 c = '$'; 2096 if (*p == ' ') 2097 p++; 2098 str = "(("; /*))*/ 2099 break; 2100 case CTLENDARI: /*((*/ 2101 c = ')'; 2102 str = ")"; 2103 break; 2104 case CTLQUOTEMARK: 2105 quoted ^= 1; 2106 c = '"'; 2107 break; 2108 case CTLQUOTEEND: 2109 quoted >>= 1; 2110 c = '"'; 2111 break; 2112 case '=': 2113 if (subtype == 0) 2114 break; 2115 str = vstype[subtype & VSTYPE]; 2116 if (subtype & VSNUL) 2117 c = ':'; 2118 else 2119 c = *str++; /*{*/ 2120 if (c != '}') 2121 quoted <<= 1; 2122 else if (*p == CTLENDVAR) 2123 c = *str++; 2124 subtype = 0; 2125 break; 2126 case '\'': 2127 case '\\': 2128 case '"': 2129 case '$': 2130 /* These can only happen inside quotes */ 2131 cc[0] = c; 2132 str = cc; 2133 c = '\\'; 2134 break; 2135 default: 2136 break; 2137 } 2138 if (c != '\0') do { /* c == 0 implies nothing in str */ 2139 *nextc++ = c; 2140 } while (--nleft > 0 && str && (c = *str++)); 2141 str = 0; 2142 } 2143 if ((quoted & 1) && nleft) { 2144 *nextc++ = '"'; 2145 nleft--; 2146 } 2147 cmdnleft = nleft; 2148 cmdnextc = nextc; 2149 } 2150
Indexes created Thu Oct 02 10:09:58 GMT 2025