1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kenneth Almquist. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 40 #endif 41 static const char rcsid[] = 42 "$FreeBSD$"; 43 #endif /* not lint */ 44 45 #include <fcntl.h> 46 #include <signal.h> 47 #include <errno.h> 48 #include <unistd.h> 49 #include <stdlib.h> 50 #include <sys/param.h> 51 #ifdef BSD 52 #include <sys/wait.h> 53 #include <sys/time.h> 54 #include <sys/resource.h> 55 #endif 56 #include <sys/ioctl.h> 57 58 #include "shell.h" 59 #if JOBS 60 #if OLD_TTY_DRIVER 61 #include "sgtty.h" 62 #else 63 #include <termios.h> 64 #endif 65 #undef CEOF /* syntax.h redefines this */ 66 #endif 67 #include "redir.h" 68 #include "show.h" 69 #include "main.h" 70 #include "parser.h" 71 #include "nodes.h" 72 #include "jobs.h" 73 #include "options.h" 74 #include "trap.h" 75 #include "syntax.h" 76 #include "input.h" 77 #include "output.h" 78 #include "memalloc.h" 79 #include "error.h" 80 #include "mystring.h" 81 82 83 struct job *jobtab; /* array of jobs */ 84 int njobs; /* size of array */ 85 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 86 #if JOBS 87 int initialpgrp; /* pgrp of shell on invocation */ 88 int curjob; /* current job */ 89 #endif 90 int in_waitcmd = 0; /* are we in waitcmd()? */ 91 int in_dowait = 0; /* are we in dowait()? */ 92 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 93 94 #if JOBS 95 STATIC void restartjob __P((struct job *)); 96 #endif 97 STATIC void freejob __P((struct job *)); 98 STATIC struct job *getjob __P((char *)); 99 STATIC int dowait __P((int, struct job *)); 100 #if SYSV 101 STATIC int onsigchild __P((void)); 102 #endif 103 STATIC int waitproc __P((int, int *)); 104 STATIC void cmdtxt __P((union node *)); 105 STATIC void cmdputs __P((char *)); 106 107 108 /* 109 * Turn job control on and off. 110 * 111 * Note: This code assumes that the third arg to ioctl is a character 112 * pointer, which is true on Berkeley systems but not System V. Since 113 * System V doesn't have job control yet, this isn't a problem now. 114 */ 115 116 MKINIT int jobctl; 117 118 #if JOBS 119 void 120 setjobctl(on) 121 int on; 122 { 123 #ifdef OLD_TTY_DRIVER 124 int ldisc; 125 #endif 126 127 if (on == jobctl || rootshell == 0) 128 return; 129 if (on) { 130 do { /* while we are in the background */ 131 #ifdef OLD_TTY_DRIVER 132 if (ioctl(2, TIOCGPGRP, (char *)&initialpgrp) < 0) { 133 #else 134 initialpgrp = tcgetpgrp(2); 135 if (initialpgrp < 0) { 136 #endif 137 out2str("sh: can't access tty; job control turned off\n"); 138 mflag = 0; 139 return; 140 } 141 if (initialpgrp == -1) 142 initialpgrp = getpgrp(); 143 else if (initialpgrp != getpgrp()) { 144 killpg(initialpgrp, SIGTTIN); 145 continue; 146 } 147 } while (0); 148 #ifdef OLD_TTY_DRIVER 149 if (ioctl(2, TIOCGETD, (char *)&ldisc) < 0 || ldisc != NTTYDISC) { 150 out2str("sh: need new tty driver to run job control; job control turned off\n"); 151 mflag = 0; 152 return; 153 } 154 #endif 155 setsignal(SIGTSTP); 156 setsignal(SIGTTOU); 157 setsignal(SIGTTIN); 158 setpgid(0, rootpid); 159 #ifdef OLD_TTY_DRIVER 160 ioctl(2, TIOCSPGRP, (char *)&rootpid); 161 #else 162 tcsetpgrp(2, rootpid); 163 #endif 164 } else { /* turning job control off */ 165 setpgid(0, initialpgrp); 166 #ifdef OLD_TTY_DRIVER 167 ioctl(2, TIOCSPGRP, (char *)&initialpgrp); 168 #else 169 tcsetpgrp(2, initialpgrp); 170 #endif 171 setsignal(SIGTSTP); 172 setsignal(SIGTTOU); 173 setsignal(SIGTTIN); 174 } 175 jobctl = on; 176 } 177 #endif 178 179 180 #ifdef mkinit 181 INCLUDE <sys/types.h> 182 INCLUDE <stdlib.h> 183 184 SHELLPROC { 185 backgndpid = -1; 186 #if JOBS 187 jobctl = 0; 188 #endif 189 } 190 191 #endif 192 193 194 195 #if JOBS 196 int 197 fgcmd(argc, argv) 198 int argc __unused; 199 char **argv; 200 { 201 struct job *jp; 202 int pgrp; 203 int status; 204 205 jp = getjob(argv[1]); 206 if (jp->jobctl == 0) 207 error("job not created under job control"); 208 pgrp = jp->ps[0].pid; 209 #ifdef OLD_TTY_DRIVER 210 ioctl(2, TIOCSPGRP, (char *)&pgrp); 211 #else 212 tcsetpgrp(2, pgrp); 213 #endif 214 restartjob(jp); 215 INTOFF; 216 status = waitforjob(jp, (int *)NULL); 217 INTON; 218 return status; 219 } 220 221 222 int 223 bgcmd(argc, argv) 224 int argc; 225 char **argv; 226 { 227 struct job *jp; 228 229 do { 230 jp = getjob(*++argv); 231 if (jp->jobctl == 0) 232 error("job not created under job control"); 233 restartjob(jp); 234 } while (--argc > 1); 235 return 0; 236 } 237 238 239 STATIC void 240 restartjob(jp) 241 struct job *jp; 242 { 243 struct procstat *ps; 244 int i; 245 246 if (jp->state == JOBDONE) 247 return; 248 INTOFF; 249 killpg(jp->ps[0].pid, SIGCONT); 250 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 251 if (WIFSTOPPED(ps->status)) { 252 ps->status = -1; 253 jp->state = 0; 254 } 255 } 256 INTON; 257 } 258 #endif 259 260 261 int 262 jobscmd(argc, argv) 263 int argc __unused; 264 char **argv __unused; 265 { 266 showjobs(0); 267 return 0; 268 } 269 270 271 /* 272 * Print a list of jobs. If "change" is nonzero, only print jobs whose 273 * statuses have changed since the last call to showjobs. 274 * 275 * If the shell is interrupted in the process of creating a job, the 276 * result may be a job structure containing zero processes. Such structures 277 * will be freed here. 278 */ 279 280 void 281 showjobs(change) 282 int change; 283 { 284 int jobno; 285 int procno; 286 int i; 287 struct job *jp; 288 struct procstat *ps; 289 int col; 290 char s[64]; 291 292 TRACE(("showjobs(%d) called\n", change)); 293 while (dowait(0, (struct job *)NULL) > 0); 294 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 295 if (! jp->used) 296 continue; 297 if (jp->nprocs == 0) { 298 freejob(jp); 299 continue; 300 } 301 if (change && ! jp->changed) 302 continue; 303 procno = jp->nprocs; 304 for (ps = jp->ps ; ; ps++) { /* for each process */ 305 if (ps == jp->ps) 306 fmtstr(s, 64, "[%d] %d ", jobno, ps->pid); 307 else 308 fmtstr(s, 64, " %d ", ps->pid); 309 out1str(s); 310 col = strlen(s); 311 s[0] = '\0'; 312 if (ps->status == -1) { 313 /* don't print anything */ 314 } else if (WIFEXITED(ps->status)) { 315 fmtstr(s, 64, "Exit %d", WEXITSTATUS(ps->status)); 316 } else { 317 #if JOBS 318 if (WIFSTOPPED(ps->status)) 319 i = WSTOPSIG(ps->status); 320 else 321 #endif 322 i = WTERMSIG(ps->status); 323 if ((i & 0x7F) < NSIG && sys_siglist[i & 0x7F]) 324 scopy(sys_siglist[i & 0x7F], s); 325 else 326 fmtstr(s, 64, "Signal %d", i & 0x7F); 327 if (WCOREDUMP(ps->status)) 328 strcat(s, " (core dumped)"); 329 } 330 out1str(s); 331 col += strlen(s); 332 do { 333 out1c(' '); 334 col++; 335 } while (col < 30); 336 out1str(ps->cmd); 337 out1c('\n'); 338 if (--procno <= 0) 339 break; 340 } 341 jp->changed = 0; 342 if (jp->state == JOBDONE) { 343 freejob(jp); 344 } 345 } 346 } 347 348 349 /* 350 * Mark a job structure as unused. 351 */ 352 353 STATIC void 354 freejob(jp) 355 struct job *jp; 356 { 357 struct procstat *ps; 358 int i; 359 360 INTOFF; 361 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 362 if (ps->cmd != nullstr) 363 ckfree(ps->cmd); 364 } 365 if (jp->ps != &jp->ps0) 366 ckfree(jp->ps); 367 jp->used = 0; 368 #if JOBS 369 if (curjob == jp - jobtab + 1) 370 curjob = 0; 371 #endif 372 INTON; 373 } 374 375 376 377 int 378 waitcmd(argc, argv) 379 int argc; 380 char **argv; 381 { 382 struct job *job; 383 int status, retval; 384 struct job *jp; 385 386 if (argc > 1) { 387 job = getjob(argv[1]); 388 } else { 389 job = NULL; 390 } 391 392 /* 393 * Loop until a process is terminated or stopped, or a SIGINT is 394 * received. 395 */ 396 397 in_waitcmd++; 398 do { 399 if (job != NULL) { 400 if (job->state) { 401 status = job->ps[job->nprocs - 1].status; 402 if (WIFEXITED(status)) 403 retval = WEXITSTATUS(status); 404 #if JOBS 405 else if (WIFSTOPPED(status)) 406 retval = WSTOPSIG(status) + 128; 407 #endif 408 else 409 retval = WTERMSIG(status) + 128; 410 if (! iflag) 411 freejob(job); 412 in_waitcmd--; 413 return retval; 414 } 415 } else { 416 for (jp = jobtab ; ; jp++) { 417 if (jp >= jobtab + njobs) { /* no running procs */ 418 in_waitcmd--; 419 return 0; 420 } 421 if (jp->used && jp->state == 0) 422 break; 423 } 424 } 425 } while (dowait(1, (struct job *)NULL) != -1); 426 in_waitcmd--; 427 428 return 0; 429 } 430 431 432 433 int 434 jobidcmd(argc, argv) 435 int argc __unused; 436 char **argv; 437 { 438 struct job *jp; 439 int i; 440 441 jp = getjob(argv[1]); 442 for (i = 0 ; i < jp->nprocs ; ) { 443 out1fmt("%d", jp->ps[i].pid); 444 out1c(++i < jp->nprocs? ' ' : '\n'); 445 } 446 return 0; 447 } 448 449 450 451 /* 452 * Convert a job name to a job structure. 453 */ 454 455 STATIC struct job * 456 getjob(name) 457 char *name; 458 { 459 int jobno; 460 struct job *jp; 461 int pid; 462 int i; 463 464 if (name == NULL) { 465 #if JOBS 466 currentjob: 467 if ((jobno = curjob) == 0 || jobtab[jobno - 1].used == 0) 468 error("No current job"); 469 return &jobtab[jobno - 1]; 470 #else 471 error("No current job"); 472 #endif 473 } else if (name[0] == '%') { 474 if (is_digit(name[1])) { 475 jobno = number(name + 1); 476 if (jobno > 0 && jobno <= njobs 477 && jobtab[jobno - 1].used != 0) 478 return &jobtab[jobno - 1]; 479 #if JOBS 480 } else if (name[1] == '%' && name[2] == '\0') { 481 goto currentjob; 482 #endif 483 } else { 484 struct job *found = NULL; 485 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 486 if (jp->used && jp->nprocs > 0 487 && prefix(name + 1, jp->ps[0].cmd)) { 488 if (found) 489 error("%s: ambiguous", name); 490 found = jp; 491 } 492 } 493 if (found) 494 return found; 495 } 496 } else if (is_number(name)) { 497 pid = number(name); 498 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 499 if (jp->used && jp->nprocs > 0 500 && jp->ps[jp->nprocs - 1].pid == pid) 501 return jp; 502 } 503 } 504 error("No such job: %s", name); 505 /*NOTREACHED*/ 506 return NULL; 507 } 508 509 510 511 /* 512 * Return a new job structure, 513 */ 514 515 struct job * 516 makejob(node, nprocs) 517 union node *node __unused; 518 int nprocs; 519 { 520 int i; 521 struct job *jp; 522 523 for (i = njobs, jp = jobtab ; ; jp++) { 524 if (--i < 0) { 525 INTOFF; 526 if (njobs == 0) { 527 jobtab = ckmalloc(4 * sizeof jobtab[0]); 528 } else { 529 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 530 memcpy(jp, jobtab, njobs * sizeof jp[0]); 531 /* Relocate `ps' pointers */ 532 for (i = 0; i < njobs; i++) 533 if (jp[i].ps == &jobtab[i].ps0) 534 jp[i].ps = &jp[i].ps0; 535 ckfree(jobtab); 536 jobtab = jp; 537 } 538 jp = jobtab + njobs; 539 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 540 INTON; 541 break; 542 } 543 if (jp->used == 0) 544 break; 545 } 546 INTOFF; 547 jp->state = 0; 548 jp->used = 1; 549 jp->changed = 0; 550 jp->nprocs = 0; 551 #if JOBS 552 jp->jobctl = jobctl; 553 #endif 554 if (nprocs > 1) { 555 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 556 } else { 557 jp->ps = &jp->ps0; 558 } 559 INTON; 560 TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs, 561 jp - jobtab + 1)); 562 return jp; 563 } 564 565 566 /* 567 * Fork of a subshell. If we are doing job control, give the subshell its 568 * own process group. Jp is a job structure that the job is to be added to. 569 * N is the command that will be evaluated by the child. Both jp and n may 570 * be NULL. The mode parameter can be one of the following: 571 * FORK_FG - Fork off a foreground process. 572 * FORK_BG - Fork off a background process. 573 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 574 * process group even if job control is on. 575 * 576 * When job control is turned off, background processes have their standard 577 * input redirected to /dev/null (except for the second and later processes 578 * in a pipeline). 579 */ 580 581 int 582 forkshell(jp, n, mode) 583 union node *n; 584 struct job *jp; 585 int mode; 586 { 587 int pid; 588 int pgrp; 589 590 TRACE(("forkshell(%%%d, 0x%lx, %d) called\n", jp - jobtab, (long)n, 591 mode)); 592 INTOFF; 593 pid = fork(); 594 if (pid == -1) { 595 TRACE(("Fork failed, errno=%d\n", errno)); 596 INTON; 597 error("Cannot fork"); 598 } 599 if (pid == 0) { 600 struct job *p; 601 int wasroot; 602 int i; 603 604 TRACE(("Child shell %d\n", getpid())); 605 wasroot = rootshell; 606 rootshell = 0; 607 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 608 if (p->used) 609 freejob(p); 610 closescript(); 611 INTON; 612 clear_traps(); 613 #if JOBS 614 jobctl = 0; /* do job control only in root shell */ 615 if (wasroot && mode != FORK_NOJOB && mflag) { 616 if (jp == NULL || jp->nprocs == 0) 617 pgrp = getpid(); 618 else 619 pgrp = jp->ps[0].pid; 620 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 621 /*** this causes superfluous TIOCSPGRPS ***/ 622 #ifdef OLD_TTY_DRIVER 623 if (ioctl(2, TIOCSPGRP, (char *)&pgrp) < 0) 624 error("TIOCSPGRP failed, errno=%d", errno); 625 #else 626 if (tcsetpgrp(2, pgrp) < 0) 627 error("tcsetpgrp failed, errno=%d", errno); 628 #endif 629 } 630 setsignal(SIGTSTP); 631 setsignal(SIGTTOU); 632 } else if (mode == FORK_BG) { 633 ignoresig(SIGINT); 634 ignoresig(SIGQUIT); 635 if ((jp == NULL || jp->nprocs == 0) && 636 ! fd0_redirected_p ()) { 637 close(0); 638 if (open("/dev/null", O_RDONLY) != 0) 639 error("Can't open /dev/null"); 640 } 641 } 642 #else 643 if (mode == FORK_BG) { 644 ignoresig(SIGINT); 645 ignoresig(SIGQUIT); 646 if ((jp == NULL || jp->nprocs == 0) && 647 ! fd0_redirected_p ()) { 648 close(0); 649 if (open("/dev/null", O_RDONLY) != 0) 650 error("Can't open /dev/null"); 651 } 652 } 653 #endif 654 if (wasroot && iflag) { 655 setsignal(SIGINT); 656 setsignal(SIGQUIT); 657 setsignal(SIGTERM); 658 } 659 return pid; 660 } 661 if (rootshell && mode != FORK_NOJOB && mflag) { 662 if (jp == NULL || jp->nprocs == 0) 663 pgrp = pid; 664 else 665 pgrp = jp->ps[0].pid; 666 setpgid(pid, pgrp); 667 } 668 if (mode == FORK_BG) 669 backgndpid = pid; /* set $! */ 670 if (jp) { 671 struct procstat *ps = &jp->ps[jp->nprocs++]; 672 ps->pid = pid; 673 ps->status = -1; 674 ps->cmd = nullstr; 675 if (iflag && rootshell && n) 676 ps->cmd = commandtext(n); 677 } 678 INTON; 679 TRACE(("In parent shell: child = %d\n", pid)); 680 return pid; 681 } 682 683 684 685 /* 686 * Wait for job to finish. 687 * 688 * Under job control we have the problem that while a child process is 689 * running interrupts generated by the user are sent to the child but not 690 * to the shell. This means that an infinite loop started by an inter- 691 * active user may be hard to kill. With job control turned off, an 692 * interactive user may place an interactive program inside a loop. If 693 * the interactive program catches interrupts, the user doesn't want 694 * these interrupts to also abort the loop. The approach we take here 695 * is to have the shell ignore interrupt signals while waiting for a 696 * foreground process to terminate, and then send itself an interrupt 697 * signal if the child process was terminated by an interrupt signal. 698 * Unfortunately, some programs want to do a bit of cleanup and then 699 * exit on interrupt; unless these processes terminate themselves by 700 * sending a signal to themselves (instead of calling exit) they will 701 * confuse this approach. 702 */ 703 704 int 705 waitforjob(jp, origstatus) 706 struct job *jp; 707 int *origstatus; 708 { 709 #if JOBS 710 int mypgrp = getpgrp(); 711 #endif 712 int status; 713 int st; 714 715 INTOFF; 716 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 717 while (jp->state == 0) 718 if (dowait(1, jp) == -1) 719 dotrap(); 720 #if JOBS 721 if (jp->jobctl) { 722 #ifdef OLD_TTY_DRIVER 723 if (ioctl(2, TIOCSPGRP, (char *)&mypgrp) < 0) 724 error("TIOCSPGRP failed, errno=%d\n", errno); 725 #else 726 if (tcsetpgrp(2, mypgrp) < 0) 727 error("tcsetpgrp failed, errno=%d\n", errno); 728 #endif 729 } 730 if (jp->state == JOBSTOPPED) 731 curjob = jp - jobtab + 1; 732 #endif 733 status = jp->ps[jp->nprocs - 1].status; 734 if (origstatus != NULL) 735 *origstatus = status; 736 /* convert to 8 bits */ 737 if (WIFEXITED(status)) 738 st = WEXITSTATUS(status); 739 #if JOBS 740 else if (WIFSTOPPED(status)) 741 st = WSTOPSIG(status) + 128; 742 #endif 743 else 744 st = WTERMSIG(status) + 128; 745 if (! JOBS || jp->state == JOBDONE) 746 freejob(jp); 747 if (int_pending()) { 748 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 749 kill(getpid(), SIGINT); 750 else 751 CLEAR_PENDING_INT; 752 } 753 INTON; 754 return st; 755 } 756 757 758 759 /* 760 * Wait for a process to terminate. 761 */ 762 763 STATIC int 764 dowait(block, job) 765 int block; 766 struct job *job; 767 { 768 int pid; 769 int status; 770 struct procstat *sp; 771 struct job *jp; 772 struct job *thisjob; 773 int done; 774 int stopped; 775 int core; 776 int sig; 777 778 in_dowait++; 779 TRACE(("dowait(%d) called\n", block)); 780 do { 781 pid = waitproc(block, &status); 782 TRACE(("wait returns %d, status=%d\n", pid, status)); 783 } while (pid == -1 && errno == EINTR && breakwaitcmd == 0); 784 in_dowait--; 785 if (breakwaitcmd != 0) { 786 breakwaitcmd = 0; 787 return -1; 788 } 789 if (pid <= 0) 790 return pid; 791 INTOFF; 792 thisjob = NULL; 793 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 794 if (jp->used) { 795 done = 1; 796 stopped = 1; 797 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 798 if (sp->pid == -1) 799 continue; 800 if (sp->pid == pid) { 801 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 802 pid, sp->status, status)); 803 sp->status = status; 804 thisjob = jp; 805 } 806 if (sp->status == -1) 807 stopped = 0; 808 else if (WIFSTOPPED(sp->status)) 809 done = 0; 810 } 811 if (stopped) { /* stopped or done */ 812 int state = done? JOBDONE : JOBSTOPPED; 813 if (jp->state != state) { 814 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 815 jp->state = state; 816 #if JOBS 817 if (done && curjob == jp - jobtab + 1) 818 curjob = 0; /* no current job */ 819 #endif 820 } 821 } 822 } 823 } 824 INTON; 825 if (! rootshell || ! iflag || (job && thisjob == job)) { 826 core = WCOREDUMP(status); 827 #if JOBS 828 if (WIFSTOPPED(status)) 829 sig = WSTOPSIG(status); 830 else 831 #endif 832 if (WIFEXITED(status)) 833 sig = 0; 834 else 835 sig = WTERMSIG(status); 836 837 if (sig != 0 && sig != SIGINT && sig != SIGPIPE) { 838 if (thisjob != job) 839 outfmt(out2, "%d: ", pid); 840 #if JOBS 841 if (sig == SIGTSTP && rootshell && iflag) 842 outfmt(out2, "%%%d ", job - jobtab + 1); 843 #endif 844 if (sig < NSIG && sys_siglist[sig]) 845 out2str(sys_siglist[sig]); 846 else 847 outfmt(out2, "Signal %d", sig); 848 if (core) 849 out2str(" - core dumped"); 850 out2c('\n'); 851 flushout(&errout); 852 } else { 853 TRACE(("Not printing status: status=%d, sig=%d\n", 854 status, sig)); 855 } 856 } else { 857 TRACE(("Not printing status, rootshell=%d, job=0x%x\n", rootshell, job)); 858 if (thisjob) 859 thisjob->changed = 1; 860 } 861 return pid; 862 } 863 864 865 866 /* 867 * Do a wait system call. If job control is compiled in, we accept 868 * stopped processes. If block is zero, we return a value of zero 869 * rather than blocking. 870 * 871 * System V doesn't have a non-blocking wait system call. It does 872 * have a SIGCLD signal that is sent to a process when one of it's 873 * children dies. The obvious way to use SIGCLD would be to install 874 * a handler for SIGCLD which simply bumped a counter when a SIGCLD 875 * was received, and have waitproc bump another counter when it got 876 * the status of a process. Waitproc would then know that a wait 877 * system call would not block if the two counters were different. 878 * This approach doesn't work because if a process has children that 879 * have not been waited for, System V will send it a SIGCLD when it 880 * installs a signal handler for SIGCLD. What this means is that when 881 * a child exits, the shell will be sent SIGCLD signals continuously 882 * until is runs out of stack space, unless it does a wait call before 883 * restoring the signal handler. The code below takes advantage of 884 * this (mis)feature by installing a signal handler for SIGCLD and 885 * then checking to see whether it was called. If there are any 886 * children to be waited for, it will be. 887 * 888 * If neither SYSV nor BSD is defined, we don't implement nonblocking 889 * waits at all. In this case, the user will not be informed when 890 * a background process until the next time she runs a real program 891 * (as opposed to running a builtin command or just typing return), 892 * and the jobs command may give out of date information. 893 */ 894 895 #ifdef SYSV 896 STATIC sig_atomic_t gotsigchild; 897 898 STATIC int onsigchild() { 899 gotsigchild = 1; 900 } 901 #endif 902 903 904 STATIC int 905 waitproc(block, status) 906 int block; 907 int *status; 908 { 909 #ifdef BSD 910 int flags; 911 912 #if JOBS 913 flags = WUNTRACED; 914 #else 915 flags = 0; 916 #endif 917 if (block == 0) 918 flags |= WNOHANG; 919 return wait3(status, flags, (struct rusage *)NULL); 920 #else 921 #ifdef SYSV 922 int (*save)(); 923 924 if (block == 0) { 925 gotsigchild = 0; 926 save = signal(SIGCLD, onsigchild); 927 signal(SIGCLD, save); 928 if (gotsigchild == 0) 929 return 0; 930 } 931 return wait(status); 932 #else 933 if (block == 0) 934 return 0; 935 return wait(status); 936 #endif 937 #endif 938 } 939 940 /* 941 * return 1 if there are stopped jobs, otherwise 0 942 */ 943 int job_warning = 0; 944 int 945 stoppedjobs() 946 { 947 int jobno; 948 struct job *jp; 949 950 if (job_warning) 951 return (0); 952 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 953 if (jp->used == 0) 954 continue; 955 if (jp->state == JOBSTOPPED) { 956 out2str("You have stopped jobs.\n"); 957 job_warning = 2; 958 return (1); 959 } 960 } 961 962 return (0); 963 } 964 965 /* 966 * Return a string identifying a command (to be printed by the 967 * jobs command. 968 */ 969 970 STATIC char *cmdnextc; 971 STATIC int cmdnleft; 972 STATIC void cmdtxt(), cmdputs(); 973 #define MAXCMDTEXT 200 974 975 char * 976 commandtext(n) 977 union node *n; 978 { 979 char *name; 980 981 cmdnextc = name = ckmalloc(MAXCMDTEXT); 982 cmdnleft = MAXCMDTEXT - 4; 983 cmdtxt(n); 984 *cmdnextc = '\0'; 985 return name; 986 } 987 988 989 STATIC void 990 cmdtxt(n) 991 union node *n; 992 { 993 union node *np; 994 struct nodelist *lp; 995 char *p; 996 int i; 997 char s[2]; 998 999 if (n == NULL) 1000 return; 1001 switch (n->type) { 1002 case NSEMI: 1003 cmdtxt(n->nbinary.ch1); 1004 cmdputs("; "); 1005 cmdtxt(n->nbinary.ch2); 1006 break; 1007 case NAND: 1008 cmdtxt(n->nbinary.ch1); 1009 cmdputs(" && "); 1010 cmdtxt(n->nbinary.ch2); 1011 break; 1012 case NOR: 1013 cmdtxt(n->nbinary.ch1); 1014 cmdputs(" || "); 1015 cmdtxt(n->nbinary.ch2); 1016 break; 1017 case NPIPE: 1018 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1019 cmdtxt(lp->n); 1020 if (lp->next) 1021 cmdputs(" | "); 1022 } 1023 break; 1024 case NSUBSHELL: 1025 cmdputs("("); 1026 cmdtxt(n->nredir.n); 1027 cmdputs(")"); 1028 break; 1029 case NREDIR: 1030 case NBACKGND: 1031 cmdtxt(n->nredir.n); 1032 break; 1033 case NIF: 1034 cmdputs("if "); 1035 cmdtxt(n->nif.test); 1036 cmdputs("; then "); 1037 cmdtxt(n->nif.ifpart); 1038 cmdputs("..."); 1039 break; 1040 case NWHILE: 1041 cmdputs("while "); 1042 goto until; 1043 case NUNTIL: 1044 cmdputs("until "); 1045 until: 1046 cmdtxt(n->nbinary.ch1); 1047 cmdputs("; do "); 1048 cmdtxt(n->nbinary.ch2); 1049 cmdputs("; done"); 1050 break; 1051 case NFOR: 1052 cmdputs("for "); 1053 cmdputs(n->nfor.var); 1054 cmdputs(" in ..."); 1055 break; 1056 case NCASE: 1057 cmdputs("case "); 1058 cmdputs(n->ncase.expr->narg.text); 1059 cmdputs(" in ..."); 1060 break; 1061 case NDEFUN: 1062 cmdputs(n->narg.text); 1063 cmdputs("() ..."); 1064 break; 1065 case NCMD: 1066 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1067 cmdtxt(np); 1068 if (np->narg.next) 1069 cmdputs(" "); 1070 } 1071 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1072 cmdputs(" "); 1073 cmdtxt(np); 1074 } 1075 break; 1076 case NARG: 1077 cmdputs(n->narg.text); 1078 break; 1079 case NTO: 1080 p = ">"; i = 1; goto redir; 1081 case NAPPEND: 1082 p = ">>"; i = 1; goto redir; 1083 case NTOFD: 1084 p = ">&"; i = 1; goto redir; 1085 case NFROM: 1086 p = "<"; i = 0; goto redir; 1087 case NFROMFD: 1088 p = "<&"; i = 0; goto redir; 1089 redir: 1090 if (n->nfile.fd != i) { 1091 s[0] = n->nfile.fd + '0'; 1092 s[1] = '\0'; 1093 cmdputs(s); 1094 } 1095 cmdputs(p); 1096 if (n->type == NTOFD || n->type == NFROMFD) { 1097 s[0] = n->ndup.dupfd + '0'; 1098 s[1] = '\0'; 1099 cmdputs(s); 1100 } else { 1101 cmdtxt(n->nfile.fname); 1102 } 1103 break; 1104 case NHERE: 1105 case NXHERE: 1106 cmdputs("<<..."); 1107 break; 1108 default: 1109 cmdputs("???"); 1110 break; 1111 } 1112 } 1113 1114 1115 1116 STATIC void 1117 cmdputs(s) 1118 char *s; 1119 { 1120 char *p, *q; 1121 char c; 1122 int subtype = 0; 1123 1124 if (cmdnleft <= 0) 1125 return; 1126 p = s; 1127 q = cmdnextc; 1128 while ((c = *p++) != '\0') { 1129 if (c == CTLESC) 1130 *q++ = *p++; 1131 else if (c == CTLVAR) { 1132 *q++ = '$'; 1133 if (--cmdnleft > 0) 1134 *q++ = '{'; 1135 subtype = *p++; 1136 } else if (c == '=' && subtype != 0) { 1137 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL]; 1138 subtype = 0; 1139 } else if (c == CTLENDVAR) { 1140 *q++ = '}'; 1141 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) 1142 cmdnleft++; /* ignore it */ 1143 else 1144 *q++ = c; 1145 if (--cmdnleft <= 0) { 1146 *q++ = '.'; 1147 *q++ = '.'; 1148 *q++ = '.'; 1149 break; 1150 } 1151 } 1152 cmdnextc = q; 1153 } 1154