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 * @(#)jobs.c 8.5 (Berkeley) 5/4/95 37 * $FreeBSD: src/bin/sh/jobs.c,v 1.72 2006/10/07 16:51:16 stefanf Exp $ 38 * $DragonFly: src/bin/sh/jobs.c,v 1.9 2007/01/13 21:27:45 pavalos Exp $ 39 */ 40 41 #include <fcntl.h> 42 #include <signal.h> 43 #include <errno.h> 44 #include <paths.h> 45 #include <unistd.h> 46 #include <stdlib.h> 47 #include <sys/param.h> 48 #include <sys/wait.h> 49 #include <sys/time.h> 50 #include <sys/resource.h> 51 #include <paths.h> 52 #include <sys/ioctl.h> 53 54 #include "shell.h" 55 #if JOBS 56 #include <termios.h> 57 #undef CEOF /* syntax.h redefines this */ 58 #endif 59 #include "redir.h" 60 #include "show.h" 61 #include "main.h" 62 #include "parser.h" 63 #include "nodes.h" 64 #include "jobs.h" 65 #include "options.h" 66 #include "trap.h" 67 #include "syntax.h" 68 #include "input.h" 69 #include "output.h" 70 #include "memalloc.h" 71 #include "error.h" 72 #include "mystring.h" 73 74 75 STATIC struct job *jobtab; /* array of jobs */ 76 STATIC int njobs; /* size of array */ 77 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 78 #if JOBS 79 STATIC struct job *jobmru; /* most recently used job list */ 80 STATIC pid_t initialpgrp; /* pgrp of shell on invocation */ 81 #endif 82 int in_waitcmd = 0; /* are we in waitcmd()? */ 83 int in_dowait = 0; /* are we in dowait()? */ 84 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 85 static int ttyfd = -1; 86 87 #if JOBS 88 STATIC void restartjob(struct job *); 89 #endif 90 STATIC void freejob(struct job *); 91 STATIC struct job *getjob(char *); 92 STATIC pid_t dowait(int, struct job *); 93 STATIC pid_t waitproc(int, int *); 94 STATIC void cmdtxt(union node *); 95 STATIC void cmdputs(const char *); 96 #if JOBS 97 STATIC void setcurjob(struct job *); 98 STATIC void deljob(struct job *); 99 STATIC struct job *getcurjob(struct job *); 100 #endif 101 STATIC void showjob(struct job *, pid_t, int); 102 103 104 /* 105 * Turn job control on and off. 106 */ 107 108 MKINIT int jobctl; 109 110 #if JOBS 111 void 112 setjobctl(int on) 113 { 114 int i; 115 116 if (on == jobctl || rootshell == 0) 117 return; 118 if (on) { 119 if (ttyfd != -1) 120 close(ttyfd); 121 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 122 i = 0; 123 while (i <= 2 && !isatty(i)) 124 i++; 125 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 126 goto out; 127 } 128 if (ttyfd < 10) { 129 /* 130 * Keep our TTY file descriptor out of the way of 131 * the user's redirections. 132 */ 133 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 134 close(ttyfd); 135 ttyfd = -1; 136 goto out; 137 } 138 close(ttyfd); 139 ttyfd = i; 140 } 141 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 142 close(ttyfd); 143 ttyfd = -1; 144 goto out; 145 } 146 do { /* while we are in the background */ 147 initialpgrp = tcgetpgrp(ttyfd); 148 if (initialpgrp < 0) { 149 out: out2str("sh: can't access tty; job control turned off\n"); 150 mflag = 0; 151 return; 152 } 153 if (initialpgrp == -1) 154 initialpgrp = getpgrp(); 155 else if (initialpgrp != getpgrp()) { 156 killpg(0, SIGTTIN); 157 continue; 158 } 159 } while (0); 160 setsignal(SIGTSTP); 161 setsignal(SIGTTOU); 162 setsignal(SIGTTIN); 163 setpgid(0, rootpid); 164 tcsetpgrp(ttyfd, rootpid); 165 } else { /* turning job control off */ 166 setpgid(0, initialpgrp); 167 tcsetpgrp(ttyfd, initialpgrp); 168 close(ttyfd); 169 ttyfd = -1; 170 setsignal(SIGTSTP); 171 setsignal(SIGTTOU); 172 setsignal(SIGTTIN); 173 } 174 jobctl = on; 175 } 176 #endif 177 178 179 #ifdef mkinit 180 INCLUDE <sys/types.h> 181 INCLUDE <stdlib.h> 182 183 SHELLPROC { 184 backgndpid = -1; 185 #if JOBS 186 jobctl = 0; 187 #endif 188 } 189 190 #endif 191 192 193 194 #if JOBS 195 int 196 fgcmd(int argc __unused, char **argv) 197 { 198 struct job *jp; 199 pid_t pgrp; 200 int status; 201 202 jp = getjob(argv[1]); 203 if (jp->jobctl == 0) 204 error("job not created under job control"); 205 out1str(jp->ps[0].cmd); 206 out1c('\n'); 207 flushout(&output); 208 pgrp = jp->ps[0].pid; 209 tcsetpgrp(ttyfd, pgrp); 210 restartjob(jp); 211 jp->foreground = 1; 212 INTOFF; 213 status = waitforjob(jp, NULL); 214 INTON; 215 return status; 216 } 217 218 219 int 220 bgcmd(int argc, char **argv) 221 { 222 char s[64]; 223 struct job *jp; 224 225 do { 226 jp = getjob(*++argv); 227 if (jp->jobctl == 0) 228 error("job not created under job control"); 229 if (jp->state == JOBDONE) 230 continue; 231 restartjob(jp); 232 jp->foreground = 0; 233 fmtstr(s, 64, "[%td] ", jp - jobtab + 1); 234 out1str(s); 235 out1str(jp->ps[0].cmd); 236 out1c('\n'); 237 } while (--argc > 1); 238 return 0; 239 } 240 241 242 STATIC void 243 restartjob(struct job *jp) 244 { 245 struct procstat *ps; 246 int i; 247 248 if (jp->state == JOBDONE) 249 return; 250 setcurjob(jp); 251 INTOFF; 252 killpg(jp->ps[0].pid, SIGCONT); 253 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 254 if (WIFSTOPPED(ps->status)) { 255 ps->status = -1; 256 jp->state = 0; 257 } 258 } 259 INTON; 260 } 261 #endif 262 263 264 int 265 jobscmd(int argc, char *argv[]) 266 { 267 char *id; 268 int ch, mode; 269 270 optind = optreset = 1; 271 opterr = 0; 272 mode = SHOWJOBS_DEFAULT; 273 while ((ch = getopt(argc, argv, "lps")) != -1) { 274 switch (ch) { 275 case 'l': 276 mode = SHOWJOBS_VERBOSE; 277 break; 278 case 'p': 279 mode = SHOWJOBS_PGIDS; 280 break; 281 case 's': 282 mode = SHOWJOBS_PIDS; 283 break; 284 case '?': 285 default: 286 error("unknown option: -%c", optopt); 287 } 288 } 289 argc -= optind; 290 argv += optind; 291 292 if (argc == 0) 293 showjobs(0, mode); 294 else 295 while ((id = *argv++) != NULL) 296 showjob(getjob(id), 0, mode); 297 298 return (0); 299 } 300 301 STATIC void 302 showjob(struct job *jp, pid_t pid, int mode) 303 { 304 char s[64]; 305 struct procstat *ps; 306 struct job *j; 307 int col, curr, i, jobno, prev, procno; 308 pid_t ppid; 309 char c; 310 311 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 312 jobno = jp - jobtab + 1; 313 curr = prev = 0; 314 #if JOBS 315 if ((j = getcurjob(NULL)) != NULL) { 316 curr = j - jobtab + 1; 317 if ((j = getcurjob(j)) != NULL) 318 prev = j - jobtab + 1; 319 } 320 #endif 321 for (ps = jp->ps ; ; ps++) { /* for each process */ 322 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 323 ppid = (mode == SHOWJOBS_PIDS) ? ps->pid : 324 getpgid(ps->pid); 325 out1fmt("%d\n", (int)ppid); 326 goto skip; 327 } 328 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps && pid == 0) 329 goto skip; 330 if (pid != 0 && pid != ps->pid) 331 goto skip; 332 if (jobno == curr && ps == jp->ps) 333 c = '+'; 334 else if (jobno == prev && ps == jp->ps) 335 c = '-'; 336 else 337 c = ' '; 338 if (ps == jp->ps) 339 fmtstr(s, 64, "[%d] %c ", jobno, c); 340 else 341 fmtstr(s, 64, " %c ", c); 342 out1str(s); 343 col = strlen(s); 344 if (mode == SHOWJOBS_VERBOSE) { 345 fmtstr(s, 64, "%d ", (int)ps->pid); 346 out1str(s); 347 col += strlen(s); 348 } 349 s[0] = '\0'; 350 if (ps != jp->ps) { 351 *s = '\0'; 352 } else if (ps->status == -1) { 353 strcpy(s, "Running"); 354 } else if (WIFEXITED(ps->status)) { 355 if (WEXITSTATUS(ps->status) == 0) 356 strcpy(s, "Done"); 357 else 358 fmtstr(s, 64, "Done (%d)", 359 WEXITSTATUS(ps->status)); 360 } else { 361 #if JOBS 362 if (WIFSTOPPED(ps->status)) 363 i = WSTOPSIG(ps->status); 364 else 365 #endif 366 i = WTERMSIG(ps->status); 367 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F]) 368 scopy(sys_siglist[i & 0x7F], s); 369 else 370 fmtstr(s, 64, "Signal %d", i & 0x7F); 371 if (WCOREDUMP(ps->status)) 372 strcat(s, " (core dumped)"); 373 } 374 out1str(s); 375 col += strlen(s); 376 do { 377 out1c(' '); 378 col++; 379 } while (col < 30); 380 out1str(ps->cmd); 381 out1c('\n'); 382 skip: if (--procno <= 0) 383 break; 384 } 385 } 386 387 /* 388 * Print a list of jobs. If "change" is nonzero, only print jobs whose 389 * statuses have changed since the last call to showjobs. 390 * 391 * If the shell is interrupted in the process of creating a job, the 392 * result may be a job structure containing zero processes. Such structures 393 * will be freed here. 394 */ 395 396 void 397 showjobs(int change, int mode) 398 { 399 int jobno; 400 struct job *jp; 401 402 TRACE(("showjobs(%d) called\n", change)); 403 while (dowait(0, NULL) > 0); 404 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 405 if (! jp->used) 406 continue; 407 if (jp->nprocs == 0) { 408 freejob(jp); 409 continue; 410 } 411 if (change && ! jp->changed) 412 continue; 413 showjob(jp, 0, mode); 414 jp->changed = 0; 415 if (jp->state == JOBDONE) { 416 freejob(jp); 417 } 418 } 419 } 420 421 422 /* 423 * Mark a job structure as unused. 424 */ 425 426 STATIC void 427 freejob(struct job *jp) 428 { 429 struct procstat *ps; 430 int i; 431 432 INTOFF; 433 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 434 if (ps->cmd != nullstr) 435 ckfree(ps->cmd); 436 } 437 if (jp->ps != &jp->ps0) 438 ckfree(jp->ps); 439 jp->used = 0; 440 #if JOBS 441 deljob(jp); 442 #endif 443 INTON; 444 } 445 446 447 448 int 449 waitcmd(int argc, char **argv) 450 { 451 struct job *job; 452 int status, retval; 453 struct job *jp; 454 455 if (argc > 1) { 456 job = getjob(argv[1]); 457 } else { 458 job = NULL; 459 } 460 461 /* 462 * Loop until a process is terminated or stopped, or a SIGINT is 463 * received. 464 */ 465 466 in_waitcmd++; 467 do { 468 if (job != NULL) { 469 if (job->state) { 470 status = job->ps[job->nprocs - 1].status; 471 if (WIFEXITED(status)) 472 retval = WEXITSTATUS(status); 473 #if JOBS 474 else if (WIFSTOPPED(status)) 475 retval = WSTOPSIG(status) + 128; 476 #endif 477 else 478 retval = WTERMSIG(status) + 128; 479 if (! iflag) 480 freejob(job); 481 in_waitcmd--; 482 return retval; 483 } 484 } else { 485 for (jp = jobtab ; ; jp++) { 486 if (jp >= jobtab + njobs) { /* no running procs */ 487 in_waitcmd--; 488 return 0; 489 } 490 if (jp->used && jp->state == 0) 491 break; 492 } 493 } 494 } while (dowait(1, NULL) != -1); 495 in_waitcmd--; 496 497 return 0; 498 } 499 500 501 502 int 503 jobidcmd(int argc __unused, char **argv) 504 { 505 struct job *jp; 506 int i; 507 508 jp = getjob(argv[1]); 509 for (i = 0 ; i < jp->nprocs ; ) { 510 out1fmt("%d", (int)jp->ps[i].pid); 511 out1c(++i < jp->nprocs? ' ' : '\n'); 512 } 513 return 0; 514 } 515 516 517 518 /* 519 * Convert a job name to a job structure. 520 */ 521 522 STATIC struct job * 523 getjob(char *name) 524 { 525 int jobno; 526 struct job *found, *jp; 527 pid_t pid; 528 int i; 529 530 if (name == NULL) { 531 #if JOBS 532 currentjob: if ((jp = getcurjob(NULL)) == NULL) 533 error("No current job"); 534 return (jp); 535 #else 536 error("No current job"); 537 #endif 538 } else if (name[0] == '%') { 539 if (is_digit(name[1])) { 540 jobno = number(name + 1); 541 if (jobno > 0 && jobno <= njobs 542 && jobtab[jobno - 1].used != 0) 543 return &jobtab[jobno - 1]; 544 #if JOBS 545 } else if (name[1] == '%' && name[2] == '\0') { 546 goto currentjob; 547 } else if (name[1] == '+' && name[2] == '\0') { 548 goto currentjob; 549 } else if (name[1] == '-' && name[2] == '\0') { 550 if ((jp = getcurjob(NULL)) == NULL || 551 (jp = getcurjob(jp)) == NULL) 552 error("No previous job"); 553 return (jp); 554 #endif 555 } else if (name[1] == '?') { 556 found = NULL; 557 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 558 if (jp->used && jp->nprocs > 0 559 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 560 if (found) 561 error("%s: ambiguous", name); 562 found = jp; 563 } 564 } 565 if (found != NULL) 566 return (found); 567 } else { 568 found = NULL; 569 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 570 if (jp->used && jp->nprocs > 0 571 && prefix(name + 1, jp->ps[0].cmd)) { 572 if (found) 573 error("%s: ambiguous", name); 574 found = jp; 575 } 576 } 577 if (found) 578 return found; 579 } 580 } else if (is_number(name)) { 581 pid = (pid_t)number(name); 582 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 583 if (jp->used && jp->nprocs > 0 584 && jp->ps[jp->nprocs - 1].pid == pid) 585 return jp; 586 } 587 } 588 error("No such job: %s", name); 589 /*NOTREACHED*/ 590 return NULL; 591 } 592 593 594 595 /* 596 * Return a new job structure, 597 */ 598 599 struct job * 600 makejob(union node *node __unused, int nprocs) 601 { 602 int i; 603 struct job *jp; 604 605 for (i = njobs, jp = jobtab ; ; jp++) { 606 if (--i < 0) { 607 INTOFF; 608 if (njobs == 0) { 609 jobtab = ckmalloc(4 * sizeof jobtab[0]); 610 #if JOBS 611 jobmru = NULL; 612 #endif 613 } else { 614 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 615 memcpy(jp, jobtab, njobs * sizeof jp[0]); 616 #if JOBS 617 /* Relocate `next' pointers and list head */ 618 if (jobmru != NULL) 619 jobmru = &jp[jobmru - jobtab]; 620 for (i = 0; i < njobs; i++) 621 if (jp[i].next != NULL) 622 jp[i].next = &jp[jp[i].next - 623 jobtab]; 624 #endif 625 /* Relocate `ps' pointers */ 626 for (i = 0; i < njobs; i++) 627 if (jp[i].ps == &jobtab[i].ps0) 628 jp[i].ps = &jp[i].ps0; 629 ckfree(jobtab); 630 jobtab = jp; 631 } 632 jp = jobtab + njobs; 633 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 634 INTON; 635 break; 636 } 637 if (jp->used == 0) 638 break; 639 } 640 INTOFF; 641 jp->state = 0; 642 jp->used = 1; 643 jp->changed = 0; 644 jp->nprocs = 0; 645 jp->foreground = 0; 646 #if JOBS 647 jp->jobctl = jobctl; 648 jp->next = NULL; 649 #endif 650 if (nprocs > 1) { 651 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 652 } else { 653 jp->ps = &jp->ps0; 654 } 655 INTON; 656 TRACE(("makejob(%p, %d) returns %%%d\n", (void *)node, nprocs, 657 jp - jobtab + 1)); 658 return jp; 659 } 660 661 #if JOBS 662 STATIC void 663 setcurjob(struct job *cj) 664 { 665 struct job *jp, *prev; 666 667 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 668 if (jp == cj) { 669 if (prev != NULL) 670 prev->next = jp->next; 671 else 672 jobmru = jp->next; 673 jp->next = jobmru; 674 jobmru = cj; 675 return; 676 } 677 } 678 cj->next = jobmru; 679 jobmru = cj; 680 } 681 682 STATIC void 683 deljob(struct job *j) 684 { 685 struct job *jp, *prev; 686 687 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 688 if (jp == j) { 689 if (prev != NULL) 690 prev->next = jp->next; 691 else 692 jobmru = jp->next; 693 return; 694 } 695 } 696 } 697 698 /* 699 * Return the most recently used job that isn't `nj', and preferably one 700 * that is stopped. 701 */ 702 STATIC struct job * 703 getcurjob(struct job *nj) 704 { 705 struct job *jp; 706 707 /* Try to find a stopped one.. */ 708 for (jp = jobmru; jp != NULL; jp = jp->next) 709 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 710 return (jp); 711 /* Otherwise the most recently used job that isn't `nj' */ 712 for (jp = jobmru; jp != NULL; jp = jp->next) 713 if (jp->used && jp != nj) 714 return (jp); 715 716 return (NULL); 717 } 718 719 #endif 720 721 /* 722 * Fork of a subshell. If we are doing job control, give the subshell its 723 * own process group. Jp is a job structure that the job is to be added to. 724 * N is the command that will be evaluated by the child. Both jp and n may 725 * be NULL. The mode parameter can be one of the following: 726 * FORK_FG - Fork off a foreground process. 727 * FORK_BG - Fork off a background process. 728 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 729 * process group even if job control is on. 730 * 731 * When job control is turned off, background processes have their standard 732 * input redirected to /dev/null (except for the second and later processes 733 * in a pipeline). 734 */ 735 736 pid_t 737 forkshell(struct job *jp, union node *n, int mode) 738 { 739 pid_t pid; 740 pid_t pgrp; 741 742 TRACE(("forkshell(%%%d, %p, %d) called\n", jp - jobtab, (void *)n, 743 mode)); 744 INTOFF; 745 flushall(); 746 pid = fork(); 747 if (pid == -1) { 748 TRACE(("Fork failed, errno=%d\n", errno)); 749 INTON; 750 error("Cannot fork: %s", strerror(errno)); 751 } 752 if (pid == 0) { 753 struct job *p; 754 int wasroot; 755 int i; 756 757 TRACE(("Child shell %d\n", (int)getpid())); 758 wasroot = rootshell; 759 rootshell = 0; 760 closescript(); 761 INTON; 762 clear_traps(); 763 #if JOBS 764 jobctl = 0; /* do job control only in root shell */ 765 if (wasroot && mode != FORK_NOJOB && mflag) { 766 if (jp == NULL || jp->nprocs == 0) 767 pgrp = getpid(); 768 else 769 pgrp = jp->ps[0].pid; 770 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 771 /*** this causes superfluous TIOCSPGRPS ***/ 772 if (tcsetpgrp(ttyfd, pgrp) < 0) 773 error("tcsetpgrp failed, errno=%d", errno); 774 } 775 setsignal(SIGTSTP); 776 setsignal(SIGTTOU); 777 } else if (mode == FORK_BG) { 778 ignoresig(SIGINT); 779 ignoresig(SIGQUIT); 780 if ((jp == NULL || jp->nprocs == 0) && 781 ! fd0_redirected_p ()) { 782 close(0); 783 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 784 error("Can't open %s: %s", 785 _PATH_DEVNULL, strerror(errno)); 786 } 787 } 788 #else 789 if (mode == FORK_BG) { 790 ignoresig(SIGINT); 791 ignoresig(SIGQUIT); 792 if ((jp == NULL || jp->nprocs == 0) && 793 ! fd0_redirected_p ()) { 794 close(0); 795 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 796 error("Can't open %s: %s", 797 _PATH_DEVNULL, strerror(errno)); 798 } 799 } 800 #endif 801 INTOFF; 802 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 803 if (p->used) 804 freejob(p); 805 INTON; 806 if (wasroot && iflag) { 807 setsignal(SIGINT); 808 setsignal(SIGQUIT); 809 setsignal(SIGTERM); 810 } 811 return pid; 812 } 813 if (rootshell && mode != FORK_NOJOB && mflag) { 814 if (jp == NULL || jp->nprocs == 0) 815 pgrp = pid; 816 else 817 pgrp = jp->ps[0].pid; 818 setpgid(pid, pgrp); 819 } 820 if (mode == FORK_BG) 821 backgndpid = pid; /* set $! */ 822 if (jp) { 823 struct procstat *ps = &jp->ps[jp->nprocs++]; 824 ps->pid = pid; 825 ps->status = -1; 826 ps->cmd = nullstr; 827 if (iflag && rootshell && n) 828 ps->cmd = commandtext(n); 829 jp->foreground = mode == FORK_FG; 830 #if JOBS 831 setcurjob(jp); 832 #endif 833 } 834 INTON; 835 TRACE(("In parent shell: child = %d\n", (int)pid)); 836 return pid; 837 } 838 839 840 841 /* 842 * Wait for job to finish. 843 * 844 * Under job control we have the problem that while a child process is 845 * running interrupts generated by the user are sent to the child but not 846 * to the shell. This means that an infinite loop started by an inter- 847 * active user may be hard to kill. With job control turned off, an 848 * interactive user may place an interactive program inside a loop. If 849 * the interactive program catches interrupts, the user doesn't want 850 * these interrupts to also abort the loop. The approach we take here 851 * is to have the shell ignore interrupt signals while waiting for a 852 * foreground process to terminate, and then send itself an interrupt 853 * signal if the child process was terminated by an interrupt signal. 854 * Unfortunately, some programs want to do a bit of cleanup and then 855 * exit on interrupt; unless these processes terminate themselves by 856 * sending a signal to themselves (instead of calling exit) they will 857 * confuse this approach. 858 */ 859 860 int 861 waitforjob(struct job *jp, int *origstatus) 862 { 863 #if JOBS 864 pid_t mypgrp = getpgrp(); 865 #endif 866 int status; 867 int st; 868 869 INTOFF; 870 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 871 while (jp->state == 0) 872 if (dowait(1, jp) == -1) 873 dotrap(); 874 #if JOBS 875 if (jp->jobctl) { 876 if (tcsetpgrp(ttyfd, mypgrp) < 0) 877 error("tcsetpgrp failed, errno=%d\n", errno); 878 } 879 if (jp->state == JOBSTOPPED) 880 setcurjob(jp); 881 #endif 882 status = jp->ps[jp->nprocs - 1].status; 883 if (origstatus != NULL) 884 *origstatus = status; 885 /* convert to 8 bits */ 886 if (WIFEXITED(status)) 887 st = WEXITSTATUS(status); 888 #if JOBS 889 else if (WIFSTOPPED(status)) 890 st = WSTOPSIG(status) + 128; 891 #endif 892 else 893 st = WTERMSIG(status) + 128; 894 if (! JOBS || jp->state == JOBDONE) 895 freejob(jp); 896 if (int_pending()) { 897 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 898 kill(getpid(), SIGINT); 899 else 900 CLEAR_PENDING_INT; 901 } 902 INTON; 903 return st; 904 } 905 906 907 908 /* 909 * Wait for a process to terminate. 910 */ 911 912 STATIC pid_t 913 dowait(int block, struct job *job) 914 { 915 pid_t pid; 916 int status; 917 struct procstat *sp; 918 struct job *jp; 919 struct job *thisjob; 920 int done; 921 int stopped; 922 int sig; 923 int i; 924 925 in_dowait++; 926 TRACE(("dowait(%d) called\n", block)); 927 do { 928 pid = waitproc(block, &status); 929 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 930 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 931 (pid > 0 && WIFSTOPPED(status) && !iflag)); 932 in_dowait--; 933 if (pid == -1 && errno == ECHILD && job != NULL) 934 job->state = JOBDONE; 935 if (breakwaitcmd != 0) { 936 breakwaitcmd = 0; 937 /* 938 * Do not early terminate if the pid is positive, else the 939 * job will not be properly recorded. 940 */ 941 if (pid <= 0) 942 return -1; 943 } 944 if (pid <= 0) 945 return pid; 946 INTOFF; 947 thisjob = NULL; 948 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 949 if (jp->used) { 950 done = 1; 951 stopped = 1; 952 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 953 if (sp->pid == -1) 954 continue; 955 if (sp->pid == pid) { 956 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 957 (int)pid, sp->status, 958 status)); 959 sp->status = status; 960 thisjob = jp; 961 } 962 if (sp->status == -1) 963 stopped = 0; 964 else if (WIFSTOPPED(sp->status)) 965 done = 0; 966 } 967 if (stopped) { /* stopped or done */ 968 int state = done? JOBDONE : JOBSTOPPED; 969 if (jp->state != state) { 970 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 971 jp->state = state; 972 #if JOBS 973 if (done) 974 deljob(jp); 975 #endif 976 } 977 } 978 } 979 } 980 INTON; 981 if (! rootshell || ! iflag || (job && thisjob == job)) { 982 #if JOBS 983 if (WIFSTOPPED(status)) 984 sig = WSTOPSIG(status); 985 else 986 #endif 987 { 988 if (WIFEXITED(status)) 989 sig = 0; 990 else 991 sig = WTERMSIG(status); 992 } 993 if (sig != 0 && sig != SIGINT && sig != SIGPIPE) { 994 if (!mflag || 995 (thisjob->foreground && !WIFSTOPPED(status))) { 996 i = WTERMSIG(status); 997 if ((i & 0x7F) < sys_nsig && sys_siglist[i & 0x7F]) 998 out1str(sys_siglist[i & 0x7F]); 999 else 1000 out1fmt("Signal %d", i & 0x7F); 1001 if (WCOREDUMP(status)) 1002 out1str(" (core dumped)"); 1003 out1c('\n'); 1004 } else 1005 showjob(thisjob, pid, SHOWJOBS_DEFAULT); 1006 } 1007 } else { 1008 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1009 if (thisjob) 1010 thisjob->changed = 1; 1011 } 1012 return pid; 1013 } 1014 1015 1016 1017 /* 1018 * Do a wait system call. If job control is compiled in, we accept 1019 * stopped processes. If block is zero, we return a value of zero 1020 * rather than blocking. 1021 */ 1022 STATIC pid_t 1023 waitproc(int block, int *status) 1024 { 1025 int flags; 1026 1027 #if JOBS 1028 flags = WUNTRACED; 1029 #else 1030 flags = 0; 1031 #endif 1032 if (block == 0) 1033 flags |= WNOHANG; 1034 return wait3(status, flags, NULL); 1035 } 1036 1037 /* 1038 * return 1 if there are stopped jobs, otherwise 0 1039 */ 1040 int job_warning = 0; 1041 int 1042 stoppedjobs(void) 1043 { 1044 int jobno; 1045 struct job *jp; 1046 1047 if (job_warning) 1048 return (0); 1049 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1050 if (jp->used == 0) 1051 continue; 1052 if (jp->state == JOBSTOPPED) { 1053 out2str("You have stopped jobs.\n"); 1054 job_warning = 2; 1055 return (1); 1056 } 1057 } 1058 1059 return (0); 1060 } 1061 1062 /* 1063 * Return a string identifying a command (to be printed by the 1064 * jobs command. 1065 */ 1066 1067 STATIC char *cmdnextc; 1068 STATIC int cmdnleft; 1069 #define MAXCMDTEXT 200 1070 1071 char * 1072 commandtext(union node *n) 1073 { 1074 char *name; 1075 1076 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1077 cmdnleft = MAXCMDTEXT - 4; 1078 cmdtxt(n); 1079 *cmdnextc = '\0'; 1080 return name; 1081 } 1082 1083 1084 STATIC void 1085 cmdtxt(union node *n) 1086 { 1087 union node *np; 1088 struct nodelist *lp; 1089 const char *p; 1090 int i; 1091 char s[2]; 1092 1093 if (n == NULL) 1094 return; 1095 switch (n->type) { 1096 case NSEMI: 1097 cmdtxt(n->nbinary.ch1); 1098 cmdputs("; "); 1099 cmdtxt(n->nbinary.ch2); 1100 break; 1101 case NAND: 1102 cmdtxt(n->nbinary.ch1); 1103 cmdputs(" && "); 1104 cmdtxt(n->nbinary.ch2); 1105 break; 1106 case NOR: 1107 cmdtxt(n->nbinary.ch1); 1108 cmdputs(" || "); 1109 cmdtxt(n->nbinary.ch2); 1110 break; 1111 case NPIPE: 1112 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1113 cmdtxt(lp->n); 1114 if (lp->next) 1115 cmdputs(" | "); 1116 } 1117 break; 1118 case NSUBSHELL: 1119 cmdputs("("); 1120 cmdtxt(n->nredir.n); 1121 cmdputs(")"); 1122 break; 1123 case NREDIR: 1124 case NBACKGND: 1125 cmdtxt(n->nredir.n); 1126 break; 1127 case NIF: 1128 cmdputs("if "); 1129 cmdtxt(n->nif.test); 1130 cmdputs("; then "); 1131 cmdtxt(n->nif.ifpart); 1132 cmdputs("..."); 1133 break; 1134 case NWHILE: 1135 cmdputs("while "); 1136 goto until; 1137 case NUNTIL: 1138 cmdputs("until "); 1139 until: 1140 cmdtxt(n->nbinary.ch1); 1141 cmdputs("; do "); 1142 cmdtxt(n->nbinary.ch2); 1143 cmdputs("; done"); 1144 break; 1145 case NFOR: 1146 cmdputs("for "); 1147 cmdputs(n->nfor.var); 1148 cmdputs(" in ..."); 1149 break; 1150 case NCASE: 1151 cmdputs("case "); 1152 cmdputs(n->ncase.expr->narg.text); 1153 cmdputs(" in ..."); 1154 break; 1155 case NDEFUN: 1156 cmdputs(n->narg.text); 1157 cmdputs("() ..."); 1158 break; 1159 case NCMD: 1160 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1161 cmdtxt(np); 1162 if (np->narg.next) 1163 cmdputs(" "); 1164 } 1165 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1166 cmdputs(" "); 1167 cmdtxt(np); 1168 } 1169 break; 1170 case NARG: 1171 cmdputs(n->narg.text); 1172 break; 1173 case NTO: 1174 p = ">"; i = 1; goto redir; 1175 case NAPPEND: 1176 p = ">>"; i = 1; goto redir; 1177 case NTOFD: 1178 p = ">&"; i = 1; goto redir; 1179 case NCLOBBER: 1180 p = ">|"; i = 1; goto redir; 1181 case NFROM: 1182 p = "<"; i = 0; goto redir; 1183 case NFROMTO: 1184 p = "<>"; i = 0; goto redir; 1185 case NFROMFD: 1186 p = "<&"; i = 0; goto redir; 1187 redir: 1188 if (n->nfile.fd != i) { 1189 s[0] = n->nfile.fd + '0'; 1190 s[1] = '\0'; 1191 cmdputs(s); 1192 } 1193 cmdputs(p); 1194 if (n->type == NTOFD || n->type == NFROMFD) { 1195 if (n->ndup.dupfd >= 0) 1196 s[0] = n->ndup.dupfd + '0'; 1197 else 1198 s[0] = '-'; 1199 s[1] = '\0'; 1200 cmdputs(s); 1201 } else { 1202 cmdtxt(n->nfile.fname); 1203 } 1204 break; 1205 case NHERE: 1206 case NXHERE: 1207 cmdputs("<<..."); 1208 break; 1209 default: 1210 cmdputs("???"); 1211 break; 1212 } 1213 } 1214 1215 1216 1217 STATIC void 1218 cmdputs(const char *s) 1219 { 1220 const char *p; 1221 char *q; 1222 char c; 1223 int subtype = 0; 1224 1225 if (cmdnleft <= 0) 1226 return; 1227 p = s; 1228 q = cmdnextc; 1229 while ((c = *p++) != '\0') { 1230 if (c == CTLESC) 1231 *q++ = *p++; 1232 else if (c == CTLVAR) { 1233 *q++ = '$'; 1234 if (--cmdnleft > 0) 1235 *q++ = '{'; 1236 subtype = *p++; 1237 } else if (c == '=' && subtype != 0) { 1238 *q++ = "}-+?="[(subtype & VSTYPE) - VSNORMAL]; 1239 subtype = 0; 1240 } else if (c == CTLENDVAR) { 1241 *q++ = '}'; 1242 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) 1243 cmdnleft++; /* ignore it */ 1244 else 1245 *q++ = c; 1246 if (--cmdnleft <= 0) { 1247 *q++ = '.'; 1248 *q++ = '.'; 1249 *q++ = '.'; 1250 break; 1251 } 1252 } 1253 cmdnextc = q; 1254 } 1255