1/* $NetBSD: jobs.c,v 1.122 2024/06/18 07:21:31 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 38static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 39#else 40__RCSID("$NetBSD: jobs.c,v 1.122 2024/06/18 07:21:31 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 95static struct job *jobtab; /* array of jobs */ 96static int njobs; /* size of array */ 97static int jobs_invalid; /* set in child */ 98MKINIT pid_t backgndpid = -1; /* pid of last background process */ 99#if JOBS 100int initialpgrp; /* pgrp of shell on invocation */ 101static int curjob = -1; /* current job */ 102#endif 103static int ttyfd = -1; 104 105STATIC void restartjob(struct job *); 106STATIC void freejob(struct job *); 107STATIC struct job *getjob(const char *, int); 108STATIC int dowait(int, struct job *, struct job **); 109#define WBLOCK 1 110#define WNOFREE 2 111#define WSILENT 4 112STATIC int jobstatus(const struct job *, int); 113STATIC int waitproc(int, struct job *, int *); 114STATIC int cmdtxt(union node *, int); 115STATIC void cmdlist(union node *, int); 116STATIC void cmdputs(const char *); 117inline static void cmdputi(int); 118 119#define JNUM(j) ((int)((j) != NULL ? ((j) - jobtab) + 1 : 0)) 120 121#ifdef SYSV 122STATIC int onsigchild(void); 123#endif 124 125#ifdef OLD_TTY_DRIVER 126static pid_t tcgetpgrp(int fd); 127static int tcsetpgrp(int fd, pid_t pgrp); 128 129static pid_t 130tcgetpgrp(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 139static int 140tcsetpgrp(int fd, pid_tpgrp) 141{ 142 return ioctl(fd, TIOCSPGRP, (char *)&pgrp); 143} 144#endif 145 146static void 147ttyfd_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 161MKINIT int jobctl; 162 163void 164setjobctl(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 238INCLUDE <stdlib.h> 239 240SHELLPROC { 241 backgndpid = -1; 242#if JOBS 243 jobctl = 0; 244#endif 245} 246 247#endif 248 249 250 251#if JOBS 252static int 253do_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 281int 282fgcmd(int argc, char **argv) 283{ 284 nextopt(""); 285 return do_fgcmd(*argptr); 286} 287 288int 289fgcmd_percent(int argc, char **argv) 290{ 291 nextopt(""); 292 return do_fgcmd(*argv); 293} 294 295static void 296set_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 342int 343bgcmd(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 367STATIC void 368restartjob(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 421inline static void 422cmdputi(int n) 423{ 424 char str[20]; 425 426 fmtstr(str, sizeof str, "%d", n); 427 cmdputs(str); 428} 429 430static void 431showjob(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 548int 549jobscmd(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 597void 598showjobs(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 646STATIC void 647freejob(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 */ 665STATIC int 666jobstatus(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 699int 700waitcmd(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 934int 935jobidcmd(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 983int 984getjobpgrp(const char *name) 985{ 986 struct job *jp; 987 988 if (jobs_invalid) 989 error("No such job: %s", name); 990 jp = getjob(name, 1); 991 if (jp == 0) 992 return 0; 993 return -jp->pgrp; 994} 995 996/* 997 * Convert a job name to a job structure. 998 */ 999 1000STATIC struct job * 1001getjob(const char *name, int noerror) 1002{ 1003 int jobno = -1; 1004 struct job *jp; 1005 int pid; 1006 int i; 1007 const char *err_msg = "No such job: %s"; 1008 1009 if (name == NULL) { 1010#if JOBS 1011 jobno = curjob; 1012#endif 1013 err_msg = "No current job"; 1014 } else if (name[0] == '%') { 1015 if (is_number(name + 1)) { 1016 jobno = number(name + 1) - 1; 1017 } else if (!name[1] || !name[2]) { 1018 switch (name[1]) { 1019#if JOBS 1020 case 0: 1021 case '+': 1022 case '%': 1023 jobno = curjob; 1024 err_msg = "No current job"; 1025 break; 1026 case '-': 1027 jobno = curjob; 1028 if (jobno != -1) 1029 jobno = jobtab[jobno].prev_job; 1030 err_msg = "No previous job"; 1031 break; 1032#endif 1033 default: 1034 goto check_pattern; 1035 } 1036 } else { 1037 struct job *found; 1038 check_pattern: 1039 found = NULL; 1040 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 1041 if (!jp->used || jp->nprocs <= 0) 1042 continue; 1043 if ((name[1] == '?' 1044 && strstr(jp->ps[0].cmd, name + 2)) 1045 || prefix(name + 1, jp->ps[0].cmd)) { 1046 if (found) { 1047 err_msg = "%s: ambiguous"; 1048 found = 0; 1049 break; 1050 } 1051 found = jp; 1052 } 1053 } 1054 if (found) 1055 return found; 1056 } 1057 1058 } else if (is_number(name)) { 1059 pid = number(name); 1060 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 1061 if (jp->used && jp->nprocs > 0 1062 && jp->ps[jp->nprocs - 1].pid == pid) 1063 return jp; 1064 } 1065 } 1066 1067 if (jobno >= 0 && jobno < njobs) { 1068 jp = jobtab + jobno; 1069 if (jp->used) 1070 return jp; 1071 } 1072 if (!noerror) 1073 error(err_msg, name); 1074 return 0; 1075} 1076 1077 1078/* 1079 * Find out if there are any running (that is, unwaited upon) 1080 * background children of the current shell. 1081 * 1082 * Return 1/0 (yes, no). 1083 * 1084 * Needed as we cannot optimise away sub-shell creation if 1085 * we have such a child, or a "wait" in that sub-shell would 1086 * observe the already existing job. 1087 */ 1088int 1089anyjobs(void) 1090{ 1091 struct job *jp; 1092 int i; 1093 1094 if (jobs_invalid) 1095 return 0; 1096 1097 for (i = njobs, jp = jobtab ; --i >= 0 ; jp++) { 1098 if (jp->used) 1099 return 1; 1100 } 1101 1102 return 0; 1103} 1104 1105/* 1106 * Output the (new) POSIX required "[%d] %d" string whenever an 1107 * async (ie: background) job is started in an interactive shell. 1108 * Note that a subshell environment is not regarded as interactive. 1109 */ 1110void 1111jobstarted(struct job *jp) 1112{ 1113 if (!iflag || !rootshell) 1114 return; 1115 1116 outfmt(out2, "[%d] %ld\n", JNUM(jp), 1117 jp->pgrp != 0 ? (long)jp->pgrp : (long)jp->ps->pid); 1118} 1119 1120/* 1121 * Return a new job structure, 1122 */ 1123 1124struct job * 1125makejob(union node *node, int nprocs) 1126{ 1127 int i; 1128 struct job *jp; 1129 1130 if (jobs_invalid) { 1131 VTRACE(DBG_JOBS, ("makejob(%p, %d) clearing jobtab (%d)\n", 1132 (void *)node, nprocs, njobs)); 1133 for (i = njobs, jp = jobtab ; --i >= 0 ; jp++) { 1134 if (jp->used) 1135 freejob(jp); 1136 } 1137 jobs_invalid = 0; 1138 } 1139 1140 for (i = njobs, jp = jobtab ; ; jp++) { 1141 if (--i < 0) { 1142 INTOFF; 1143 if (njobs == 0) { 1144 jobtab = ckmalloc(4 * sizeof jobtab[0]); 1145 } else { 1146 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 1147 memcpy(jp, jobtab, njobs * sizeof jp[0]); 1148 /* Relocate `ps' pointers */ 1149 for (i = 0; i < njobs; i++) 1150 if (jp[i].ps == &jobtab[i].ps0) 1151 jp[i].ps = &jp[i].ps0; 1152 ckfree(jobtab); 1153 jobtab = jp; 1154 } 1155 jp = jobtab + njobs; 1156 for (i = 4 ; --i >= 0 ; njobs++) { 1157 jobtab[njobs].used = 0; 1158 jobtab[njobs].prev_job = -1; 1159 } 1160 INTON; 1161 break; 1162 } 1163 if (jp->used == 0) 1164 break; 1165 } 1166 INTOFF; 1167 jp->state = JOBRUNNING; 1168 jp->used = 1; 1169 jp->flags = pipefail ? JPIPEFAIL : 0; 1170 jp->nprocs = 0; 1171 jp->pgrp = 0; 1172#if JOBS 1173 jp->jobctl = jobctl; 1174 set_curjob(jp, 1); 1175#endif 1176 if (nprocs > 1) { 1177 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 1178 } else { 1179 jp->ps = &jp->ps0; 1180 } 1181 INTON; 1182 VTRACE(DBG_JOBS, ("makejob(%p, %d)%s returns %%%d\n", (void *)node, 1183 nprocs, (jp->flags & JPIPEFAIL) ? " PF" : "", JNUM(jp))); 1184 return jp; 1185} 1186 1187 1188/* 1189 * Fork off a subshell. If we are doing job control, give the subshell its 1190 * own process group. Jp is a job structure that the job is to be added to. 1191 * N is the command that will be evaluated by the child. Both jp and n may 1192 * be NULL. The mode parameter can be one of the following: 1193 * FORK_FG - Fork off a foreground process. 1194 * FORK_BG - Fork off a background process. 1195 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 1196 * process group even if job control is on. 1197 * 1198 * When job control is turned off, background processes have their standard 1199 * input redirected to /dev/null (except for the second and later processes 1200 * in a pipeline). 1201 */ 1202 1203int 1204forkshell(struct job *jp, union node *n, int mode) 1205{ 1206 pid_t pid; 1207 int serrno; 1208 1209 CTRACE(DBG_JOBS, ("forkshell(%%%d, %p, %d) called\n", 1210 JNUM(jp), n, mode)); 1211 1212 switch ((pid = fork())) { 1213 case -1: 1214 serrno = errno; 1215 VTRACE(DBG_JOBS, ("Fork failed, errno=%d\n", serrno)); 1216 error("Cannot fork (%s)", strerror(serrno)); 1217 break; 1218 case 0: 1219 SHELL_FORKED(); 1220 forkchild(jp, n, mode, 0); 1221 return 0; 1222 default: 1223 return forkparent(jp, n, mode, pid); 1224 } 1225} 1226 1227int 1228forkparent(struct job *jp, union node *n, int mode, pid_t pid) 1229{ 1230 int pgrp = 0; 1231 1232 if (rootshell && mode != FORK_NOJOB && mflag) { 1233 /* 1234 * The process group ID must always be that of the 1235 * first process created for the job. If this proc 1236 * is the first, that's us, otherwise the pgrp has 1237 * already been determined. 1238 */ 1239 if (jp == NULL || jp->nprocs == 0) 1240 pgrp = pid; 1241 else 1242 pgrp = jp->pgrp; 1243 /* This can fail because we are doing it in the child also */ 1244 (void)setpgid(pid, pgrp); 1245 } 1246 if (mode == FORK_BG) 1247 backgndpid = pid; /* set $! */ 1248 if (jp) { 1249 struct procstat *ps = &jp->ps[jp->nprocs++]; 1250 ps->pid = pid; 1251 ps->status = -1; 1252 ps->cmd[0] = 0; 1253 jp->pgrp = pgrp; /* 0 if !mflag */ 1254 if (/* iflag && rootshell && */ n) 1255 commandtext(ps, n); 1256 } 1257 CTRACE(DBG_JOBS, ("In parent shell: child = %d (mode %d)\n",pid,mode)); 1258 return pid; 1259} 1260 1261void 1262forkchild(struct job *jp, union node *n, int mode, int vforked) 1263{ 1264 int wasroot; 1265 int pgrp; 1266 const char *devnull = _PATH_DEVNULL; 1267 const char *nullerr = "Can't open %s"; 1268 1269 wasroot = rootshell; 1270 CTRACE(DBG_JOBS, ("Child shell %d %sforked from %d (mode %d)\n", 1271 getpid(), vforked?"v":"", getppid(), mode)); 1272 1273 if (!vforked) { 1274 rootshell = 0; 1275 handler = &main_handler; 1276 } 1277 1278 closescript(vforked); 1279 clear_traps(vforked); 1280#if JOBS 1281 if (!vforked) 1282 jobctl = 0; /* do job control only in root shell */ 1283 if (wasroot && mode != FORK_NOJOB && mflag) { 1284 if (jp == NULL || jp->nprocs == 0) 1285 pgrp = getpid(); 1286 else 1287 pgrp = jp->ps[0].pid; 1288 /* This can fail because we are doing it in the parent also */ 1289 (void)setpgid(0, pgrp); 1290 if (mode == FORK_FG) { 1291 if (tcsetpgrp(ttyfd, pgrp) == -1) 1292 error("Cannot set tty process group (%s) at %d", 1293 strerror(errno), __LINE__); 1294 } 1295 setsignal(SIGTSTP, vforked); 1296 setsignal(SIGTTOU, vforked); 1297 } else if (mode == FORK_BG) { 1298 ignoresig(SIGINT, vforked); 1299 ignoresig(SIGQUIT, vforked); 1300 if ((jp == NULL || jp->nprocs == 0) && 1301 ! fd0_redirected_p ()) { 1302 close(0); 1303 if (open(devnull, O_RDONLY) != 0) 1304 error(nullerr, devnull); 1305 } 1306 } 1307#else 1308 if (mode == FORK_BG) { 1309 ignoresig(SIGINT, vforked); 1310 ignoresig(SIGQUIT, vforked); 1311 if ((jp == NULL || jp->nprocs == 0) && 1312 ! fd0_redirected_p ()) { 1313 close(0); 1314 if (open(devnull, O_RDONLY) != 0) 1315 error(nullerr, devnull); 1316 } 1317 } 1318#endif 1319 if (wasroot && iflag) { 1320 setsignal(SIGINT, vforked); 1321 setsignal(SIGQUIT, vforked); 1322 setsignal(SIGTERM, vforked); 1323 } 1324 1325 if (!vforked) 1326 jobs_invalid = 1; 1327} 1328 1329/* 1330 * Wait for job to finish. 1331 * 1332 * Under job control we have the problem that while a child process is 1333 * running interrupts generated by the user are sent to the child but not 1334 * to the shell. This means that an infinite loop started by an inter- 1335 * active user may be hard to kill. With job control turned off, an 1336 * interactive user may place an interactive program inside a loop. If 1337 * the interactive program catches interrupts, the user doesn't want 1338 * these interrupts to also abort the loop. The approach we take here 1339 * is to have the shell ignore interrupt signals while waiting for a 1340 * foreground process to terminate, and then send itself an interrupt 1341 * signal if the child process was terminated by an interrupt signal. 1342 * Unfortunately, some programs want to do a bit of cleanup and then 1343 * exit on interrupt; unless these processes terminate themselves by 1344 * sending a signal to themselves (instead of calling exit) they will 1345 * confuse this approach. 1346 */ 1347 1348int 1349waitforjob(struct job *jp) 1350{ 1351#if JOBS 1352 int mypgrp = getpgrp(); 1353#endif 1354 int status; 1355 int st; 1356 1357 INTOFF; 1358 VTRACE(DBG_JOBS, ("waitforjob(%%%d) called\n", JNUM(jp))); 1359 while (jp->state == JOBRUNNING) { 1360 dowait(WBLOCK, jp, NULL); 1361 } 1362#if JOBS 1363 if (jp->jobctl) { 1364 if (tcsetpgrp(ttyfd, mypgrp) == -1) 1365 error("Cannot set tty process group (%s) at %d", 1366 strerror(errno), __LINE__); 1367 } 1368 if (jp->state == JOBSTOPPED && curjob != jp - jobtab) 1369 set_curjob(jp, 2); 1370#endif 1371 status = jobstatus(jp, 1); 1372 1373 /* convert to 8 bits */ 1374 if (WIFEXITED(status)) 1375 st = WEXITSTATUS(status); 1376#if JOBS 1377 else if (WIFSTOPPED(status)) 1378 st = WSTOPSIG(status) + 128; 1379#endif 1380 else 1381 st = WTERMSIG(status) + 128; 1382 1383 VTRACE(DBG_JOBS, ("waitforjob: job %d, nproc %d, status %d, st %x\n", 1384 JNUM(jp), jp->nprocs, status, st)); 1385#if JOBS 1386 if (jp->jobctl) { 1387 /* 1388 * This is truly gross. 1389 * If we're doing job control, then we did a TIOCSPGRP which 1390 * caused us (the shell) to no longer be in the controlling 1391 * session -- so we wouldn't have seen any ^C/SIGINT. So, we 1392 * intuit from the subprocess exit status whether a SIGINT 1393 * occurred, and if so interrupt ourselves. Yuck. - mycroft 1394 */ 1395 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 1396 raise(SIGINT); 1397 } 1398#endif 1399 if (! JOBS || jp->state == JOBDONE) 1400 freejob(jp); 1401 INTON; 1402 return st; 1403} 1404 1405 1406 1407/* 1408 * Wait for a process (any process) to terminate. 1409 * 1410 * If "job" is given (not NULL), then its jobcontrol status (and mflag) 1411 * are used to determine if we wait for stopping/continuing processes or 1412 * only terminating ones, and the decision whether to report to stdout 1413 * or not varies depending what happened, and whether the affected job 1414 * is the one that was requested or not. 1415 * 1416 * If "changed" is not NULL, then the job which changed because a 1417 * process terminated/stopped will be reported by setting *changed, 1418 * if there is any such job, otherwise we set *changed = NULL. 1419 */ 1420 1421STATIC int 1422dowait(int flags, struct job *job, struct job **changed) 1423{ 1424 int pid; 1425 int status; 1426 struct procstat *sp; 1427 struct job *jp; 1428 struct job *thisjob; 1429 int done; 1430 int stopped; 1431 int err; 1432 1433 VTRACE(DBG_JOBS|DBG_PROCS, ("dowait(%x) called for job %d%s\n", 1434 flags, JNUM(job), changed ? " [report change]" : "")); 1435 1436 if (changed != NULL) 1437 *changed = NULL; 1438 1439 /* 1440 * First deal with the kernel, collect info on any (one) of our 1441 * children that has changed state since we last asked. 1442 * (loop if we're interrupted by a signal that we aren't processing) 1443 */ 1444 do { 1445 err = 0; 1446 pid = waitproc(flags & WBLOCK, job, &status); 1447 if (pid == -1) 1448 err = errno; 1449 VTRACE(DBG_JOBS|DBG_PROCS, 1450 ("wait returns pid %d (e:%d), status %#x (ps=%d)\n", 1451 pid, err, status, pendingsigs)); 1452 } while (pid == -1 && err == EINTR && pendingsigs == 0); 1453 1454 /* 1455 * if nothing exited/stopped/..., we have nothing else to do 1456 */ 1457 if (pid <= 0) 1458 return pid; 1459 1460 /* 1461 * Otherwise, try to find the process, somewhere in our job table 1462 */ 1463 INTOFF; 1464 thisjob = NULL; 1465 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1466 if (jp->used) { 1467 /* 1468 * For each job that is in use (this is one) 1469 */ 1470 done = 1; /* assume it is finished */ 1471 stopped = 1; /* and has stopped */ 1472 1473 /* 1474 * Now scan all our child processes of the job 1475 */ 1476 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1477 if (sp->pid == -1) 1478 continue; 1479 /* 1480 * If the process that changed is the one 1481 * we're looking at, and it was previously 1482 * running (-1) or was stopped (anything else 1483 * and it must have already finished earlier, 1484 * so cannot be the process that just changed) 1485 * then we update its status 1486 */ 1487 if (sp->pid == pid && 1488 (sp->status==-1 || WIFSTOPPED(sp->status))) { 1489 VTRACE(DBG_JOBS | DBG_PROCS, 1490 ("Job %d: changing status of proc %d from %#x to ", 1491 JNUM(jp), pid, sp->status)); 1492 1493 /* 1494 * If the process continued, 1495 * then update its status to running 1496 * and mark the job running as well. 1497 * 1498 * If it was anything but running 1499 * before, flag it as a change for 1500 * reporting purposes later 1501 */ 1502 if (WIFCONTINUED(status)) { 1503 if (sp->status != -1) 1504 jp->flags |= JOBCHANGED; 1505 sp->status = -1; 1506 jp->state = JOBRUNNING; 1507 VTRACE(DBG_JOBS|DBG_PROCS, 1508 ("running\n")); 1509 } else { 1510 /* otherwise update status */ 1511 sp->status = status; 1512 VTRACE(DBG_JOBS|DBG_PROCS, 1513 ("%#x\n", status)); 1514 } 1515 1516 /* 1517 * We now know the affected job 1518 */ 1519 thisjob = jp; 1520 if (changed != NULL) 1521 *changed = jp; 1522 } 1523 /* 1524 * After any update that might have just 1525 * happened, if this process is running, 1526 * the job is not stopped, or if the process 1527 * simply stopped (not terminated) then the 1528 * job is certainly not completed (done). 1529 */ 1530 if (sp->status == -1) 1531 stopped = 0; 1532 else if (WIFSTOPPED(sp->status)) 1533 done = 0; 1534 } 1535 1536 /* 1537 * Once we have examined all processes for the 1538 * job, if we still show it as stopped, then... 1539 */ 1540 if (stopped) { /* stopped or done */ 1541 /* 1542 * it might be stopped, or finished, decide: 1543 */ 1544 int state = done ? JOBDONE : JOBSTOPPED; 1545 1546 /* 1547 * If that wasn't the same as it was before 1548 * then update its state, and if it just 1549 * completed, make it be the current job (%%) 1550 */ 1551 if (jp->state != state) { 1552 VTRACE(DBG_JOBS, 1553 ("Job %d: changing state from %d to %d\n", 1554 JNUM(jp), jp->state, state)); 1555 jp->state = state; 1556#if JOBS 1557 if (done) 1558 set_curjob(jp, 0); 1559#endif 1560 } 1561 } 1562 } 1563 } 1564 1565 /* 1566 * Now we have scanned all jobs. If we found the job that 1567 * the process that changed state belonged to (we occasionally 1568 * fork processes without associating them with a job, when one 1569 * of those finishes, we simply ignore it, the zombie has been 1570 * cleaned up, which is all that matters) then we need to 1571 * determine if we should say something about it to stdout 1572 */ 1573 1574 if (thisjob && 1575 (thisjob->state != JOBRUNNING || thisjob->flags & JOBCHANGED)) { 1576 int mode = 0; 1577 1578 if (!rootshell || !iflag) 1579 mode = SHOW_SIGNALLED; 1580 if ((job == thisjob && (flags & WNOFREE) == 0) || 1581 job != thisjob) 1582 mode = SHOW_SIGNALLED | SHOW_NO_FREE; 1583 if (mode && (flags & WSILENT) == 0) 1584 showjob(out2, thisjob, mode); 1585 else { 1586 VTRACE(DBG_JOBS, 1587 ("Not printing status for %p [%d], " 1588 "mode=%#x rootshell=%d, job=%p [%d]\n", 1589 thisjob, JNUM(thisjob), mode, rootshell, 1590 job, JNUM(job))); 1591 thisjob->flags |= JOBCHANGED; 1592 } 1593 } 1594 1595 INTON; 1596 /* 1597 * Finally tell our caller that something happened (in general all 1598 * anyone tests for is <= 0 (or >0) so the actual pid value here 1599 * doesn't matter much, but we know pid is >0 so we may as well 1600 * give back something meaningful 1601 */ 1602 return pid; 1603} 1604 1605 1606 1607/* 1608 * Do a wait system call. If job control is compiled in, we accept 1609 * stopped processes. If block is zero, we return a value of zero 1610 * rather than blocking. 1611 * 1612 * System V doesn't have a non-blocking wait system call. It does 1613 * have a SIGCLD signal that is sent to a process when one of its 1614 * children dies. The obvious way to use SIGCLD would be to install 1615 * a handler for SIGCLD which simply bumped a counter when a SIGCLD 1616 * was received, and have waitproc bump another counter when it got 1617 * the status of a process. Waitproc would then know that a wait 1618 * system call would not block if the two counters were different. 1619 * This approach doesn't work because if a process has children that 1620 * have not been waited for, System V will send it a SIGCLD when it 1621 * installs a signal handler for SIGCLD. What this means is that when 1622 * a child exits, the shell will be sent SIGCLD signals continuously 1623 * until is runs out of stack space, unless it does a wait call before 1624 * restoring the signal handler. The code below takes advantage of 1625 * this (mis)feature by installing a signal handler for SIGCLD and 1626 * then checking to see whether it was called. If there are any 1627 * children to be waited for, it will be. 1628 * 1629 * If neither SYSV nor BSD is defined, we don't implement nonblocking 1630 * waits at all. In this case, the user will not be informed when 1631 * a background process ends until the next time she runs a real program 1632 * (as opposed to running a builtin command or just typing return), 1633 * and the jobs command may give out of date information. 1634 */ 1635 1636#ifdef SYSV 1637STATIC int gotsigchild; 1638 1639STATIC int onsigchild() { 1640 gotsigchild = 1; 1641} 1642#endif 1643 1644 1645STATIC int 1646waitproc(int block, struct job *jp, int *status) 1647{ 1648#ifdef BSD 1649 int flags = 0; 1650 1651#if JOBS 1652 if (mflag || (jp != NULL && jp->jobctl)) 1653 flags |= WUNTRACED | WCONTINUED; 1654#endif 1655 if (block == 0) 1656 flags |= WNOHANG; 1657 VTRACE(DBG_WAIT, ("waitproc: doing waitpid(flags=%#x)\n", flags)); 1658 return waitpid(-1, status, flags); 1659#else 1660#ifdef SYSV 1661 int (*save)(); 1662 1663 if (block == 0) { 1664 gotsigchild = 0; 1665 save = signal(SIGCLD, onsigchild); 1666 signal(SIGCLD, save); 1667 if (gotsigchild == 0) 1668 return 0; 1669 } 1670 return wait(status); 1671#else 1672 if (block == 0) 1673 return 0; 1674 return wait(status); 1675#endif 1676#endif 1677} 1678 1679/* 1680 * return 1 if there are stopped jobs, otherwise 0 1681 */ 1682int job_warning = 0; 1683int 1684stoppedjobs(void) 1685{ 1686 int jobno; 1687 struct job *jp; 1688 1689 if (job_warning || jobs_invalid) 1690 return (0); 1691 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1692 if (jp->used == 0) 1693 continue; 1694 if (jp->state == JOBSTOPPED) { 1695 out2str("You have stopped jobs.\n"); 1696 job_warning = 2; 1697 return (1); 1698 } 1699 } 1700 1701 return (0); 1702} 1703 1704/* 1705 * Return a string identifying a command (to be printed by the 1706 * jobs command). 1707 */ 1708 1709STATIC char *cmdnextc; 1710STATIC int cmdnleft; 1711 1712void 1713commandtext(struct procstat *ps, union node *n) 1714{ 1715 int len; 1716 1717 cmdnextc = ps->cmd; 1718 if (iflag || mflag || sizeof(ps->cmd) <= 60) 1719 len = sizeof(ps->cmd); 1720 else if (sizeof ps->cmd <= 400) 1721 len = 50; 1722 else if (sizeof ps->cmd <= 800) 1723 len = 80; 1724 else 1725 len = sizeof(ps->cmd) / 10; 1726 cmdnleft = len; 1727 (void)cmdtxt(n, 1); 1728 if (cmdnleft <= 0) { 1729 char *p = ps->cmd + len - 4; 1730 p[0] = '.'; 1731 p[1] = '.'; 1732 p[2] = '.'; 1733 p[3] = 0; 1734 } else 1735 *cmdnextc = '\0'; 1736 1737 VTRACE(DBG_JOBS, 1738 ("commandtext: ps->cmd %p, end %p, left %d\n\t\"%s\"\n", 1739 ps->cmd, cmdnextc, cmdnleft, ps->cmd)); 1740} 1741 1742 1743/* 1744 * Generate a string describing tree node n & its descendants (recursive calls) 1745 * 1746 * Return true (non-zero) if the output is complete (ends with an operator) 1747 * so no ';' need be added before the following command. Return false (zero) 1748 * if a ';' is needed to terminate the output if it is followed by something 1749 * which is not an operator. 1750 */ 1751STATIC int 1752cmdtxt(union node *n, int top) 1753{ 1754 union node *np; 1755 struct nodelist *lp; 1756 const char *p; 1757 int i; 1758 1759 if (n == NULL || cmdnleft <= 0) 1760 return 1; 1761 switch (n->type) { 1762 case NSEMI: 1763 if (!cmdtxt(n->nbinary.ch1, 0)) 1764 cmdputs(";"); 1765 cmdputs(" "); 1766 return cmdtxt(n->nbinary.ch2, 0); 1767 case NAND: 1768 (void)cmdtxt(n->nbinary.ch1, 0); 1769 cmdputs(" && "); 1770 return cmdtxt(n->nbinary.ch2, 0); 1771 case NOR: 1772 (void) cmdtxt(n->nbinary.ch1, 0); 1773 cmdputs(" || "); 1774 return cmdtxt(n->nbinary.ch2, 0); 1775 case NDNOT: 1776 cmdputs("! "); 1777 /* FALLTHROUGH */ 1778 case NNOT: 1779 cmdputs("! "); 1780 return cmdtxt(n->nnot.com, 0); 1781 break; 1782 case NPIPE: 1783 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1784 (void) cmdtxt(lp->n, 0); 1785 if (lp->next) 1786 cmdputs(" | "); 1787 } 1788 if (!top && n->npipe.backgnd) { 1789 cmdputs(" &"); 1790 return 1; 1791 } 1792 return 0; 1793 case NSUBSHELL: 1794 cmdputs("("); 1795 (void) cmdtxt(n->nredir.n, 0); 1796 cmdputs(")"); 1797 return 0; 1798 case NREDIR: 1799 case NBACKGND: 1800 return cmdtxt(n->nredir.n, top); 1801 case NIF: 1802 cmdputs("if "); 1803 if (!cmdtxt(n->nif.test, 0)) 1804 cmdputs(";"); 1805 cmdputs(" then "); 1806 i = cmdtxt(n->nif.ifpart, 0); 1807 if (n->nif.elsepart) { 1808 if (i == 0) 1809 cmdputs(";"); 1810 cmdputs(" else "); 1811 i = cmdtxt(n->nif.elsepart, 0); 1812 } 1813 if (i == 0) 1814 cmdputs(";"); 1815 cmdputs(" fi"); 1816 return 0; 1817 case NWHILE: 1818 cmdputs("while "); 1819 goto until; 1820 case NUNTIL: 1821 cmdputs("until "); 1822 until: 1823 if (!cmdtxt(n->nbinary.ch1, 0)) 1824 cmdputs(";"); 1825 cmdputs(" do "); 1826 if (!cmdtxt(n->nbinary.ch2, 0)) 1827 cmdputs(";"); 1828 cmdputs(" done"); 1829 return 0; 1830 case NFOR: 1831 cmdputs("for "); 1832 cmdputs(n->nfor.var); 1833 cmdputs(" in "); 1834 cmdlist(n->nfor.args, 1); 1835 cmdputs("; do "); 1836 if (!cmdtxt(n->nfor.body, 0)) 1837 cmdputs(";"); 1838 cmdputs(" done"); 1839 return 0; 1840 case NCASE: 1841 cmdputs("case "); 1842 cmdputs(n->ncase.expr->narg.text); 1843 cmdputs(" in "); 1844 for (np = n->ncase.cases; np; np = np->nclist.next) { 1845 (void) cmdtxt(np->nclist.pattern, 0); 1846 cmdputs(") "); 1847 (void) cmdtxt(np->nclist.body, 0); 1848 switch (n->type) { /* switch (not if) for later */ 1849 case NCLISTCONT: 1850 cmdputs(" ;& "); 1851 break; 1852 default: 1853 cmdputs(" ;; "); 1854 break; 1855 } 1856 } 1857 cmdputs("esac"); 1858 return 0; 1859 case NDEFUN: 1860 cmdputs(n->narg.text); 1861 cmdputs("() { ... }"); 1862 return 0; 1863 case NCMD: 1864 cmdlist(n->ncmd.args, 1); 1865 cmdlist(n->ncmd.redirect, 0); 1866 if (!top && n->ncmd.backgnd) { 1867 cmdputs(" &"); 1868 return 1; 1869 } 1870 return 0; 1871 case NARG: 1872 cmdputs(n->narg.text); 1873 return 0; 1874 case NTO: 1875 p = ">"; i = 1; goto redir; 1876 case NCLOBBER: 1877 p = ">|"; i = 1; goto redir; 1878 case NAPPEND: 1879 p = ">>"; i = 1; goto redir; 1880 case NTOFD: 1881 p = ">&"; i = 1; goto redir; 1882 case NFROM: 1883 p = "<"; i = 0; goto redir; 1884 case NFROMFD: 1885 p = "<&"; i = 0; goto redir; 1886 case NFROMTO: 1887 p = "<>"; i = 0; goto redir; 1888 redir: 1889 if (n->nfile.fd != i) 1890 cmdputi(n->nfile.fd); 1891 cmdputs(p); 1892 if (n->type == NTOFD || n->type == NFROMFD) { 1893 if (n->ndup.dupfd < 0) 1894 cmdputs("-"); 1895 else 1896 cmdputi(n->ndup.dupfd); 1897 } else { 1898 (void) cmdtxt(n->nfile.fname, 0); 1899 } 1900 return 0; 1901 case NHERE: 1902 case NXHERE: 1903 cmdputs("<<..."); 1904 return 0; 1905 default: 1906 cmdputs("???"); 1907 return 0; 1908 } 1909 return 0; 1910} 1911 1912STATIC void 1913cmdlist(union node *np, int sep) 1914{ 1915 for (; np; np = np->narg.next) { 1916 if (!sep) 1917 cmdputs(" "); 1918 (void) cmdtxt(np, 0); 1919 if (sep && np->narg.next) 1920 cmdputs(" "); 1921 } 1922} 1923 1924 1925STATIC void 1926cmdputs(const char *s) 1927{ 1928 const char *p, *str = 0; 1929 char c, cc[2] = " "; 1930 char *nextc; 1931 int nleft; 1932 int subtype = 0; 1933 int quoted = 0; 1934 static char vstype[16][4] = { "", "}", "-", "+", "?", "=", 1935 "#", "##", "%", "%%", "}" }; 1936 1937 p = s; 1938 nextc = cmdnextc; 1939 nleft = cmdnleft; 1940 while (nleft > 0 && (c = *p++) != 0) { 1941 switch (c) { 1942 case CTLNONL: 1943 c = '\0'; 1944 break; 1945 case CTLESC: 1946 c = *p++; 1947 break; 1948 case CTLVAR: 1949 subtype = *p++; 1950 if (subtype & VSLINENO) { /* undo LINENO hack */ 1951 if ((subtype & VSTYPE) == VSLENGTH) 1952 str = "${#LINENO"; /*}*/ 1953 else 1954 str = "${LINENO"; /*}*/ 1955 while (is_digit(*p)) 1956 p++; 1957 } else if ((subtype & VSTYPE) == VSLENGTH) 1958 str = "${#"; /*}*/ 1959 else 1960 str = "${"; /*}*/ 1961 if (!(subtype & VSQUOTE) != !(quoted & 1)) { 1962 quoted ^= 1; 1963 c = '"'; 1964 } else { 1965 c = *str++; 1966 } 1967 break; 1968 case CTLENDVAR: /*{*/ 1969 c = '}'; 1970 if (quoted & 1) 1971 str = "\""; 1972 quoted >>= 1; 1973 subtype = 0; 1974 break; 1975 case CTLBACKQ: 1976 c = '$'; 1977 str = "(...)"; 1978 break; 1979 case CTLBACKQ+CTLQUOTE: 1980 c = '"'; 1981 str = "$(...)\""; 1982 break; 1983 case CTLARI: 1984 c = '$'; 1985 if (*p == ' ') 1986 p++; 1987 str = "(("; /*))*/ 1988 break; 1989 case CTLENDARI: /*((*/ 1990 c = ')'; 1991 str = ")"; 1992 break; 1993 case CTLQUOTEMARK: 1994 quoted ^= 1; 1995 c = '"'; 1996 break; 1997 case CTLQUOTEEND: 1998 quoted >>= 1; 1999 c = '"'; 2000 break; 2001 case '=': 2002 if (subtype == 0) 2003 break; 2004 str = vstype[subtype & VSTYPE]; 2005 if (subtype & VSNUL) 2006 c = ':'; 2007 else 2008 c = *str++; /*{*/ 2009 if (c != '}') 2010 quoted <<= 1; 2011 else if (*p == CTLENDVAR) 2012 c = *str++; 2013 subtype = 0; 2014 break; 2015 case '\'': 2016 case '\\': 2017 case '"': 2018 case '$': 2019 /* These can only happen inside quotes */ 2020 cc[0] = c; 2021 str = cc; 2022 c = '\\'; 2023 break; 2024 default: 2025 break; 2026 } 2027 if (c != '\0') do { /* c == 0 implies nothing in str */ 2028 *nextc++ = c; 2029 } while (--nleft > 0 && str && (c = *str++)); 2030 str = 0; 2031 } 2032 if ((quoted & 1) && nleft) { 2033 *nextc++ = '"'; 2034 nleft--; 2035 } 2036 cmdnleft = nleft; 2037 cmdnextc = nextc; 2038} 2039