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 1.95 2011/06/13 21:03:27 jilles Exp $ 38 */ 39 40 #include <sys/ioctl.h> 41 #include <sys/param.h> 42 #include <sys/resource.h> 43 #include <sys/time.h> 44 #include <sys/wait.h> 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <paths.h> 48 #include <signal.h> 49 #include <stddef.h> 50 #include <stdlib.h> 51 #include <unistd.h> 52 53 #include "shell.h" 54 #if JOBS 55 #include <termios.h> 56 #undef CEOF /* syntax.h redefines this */ 57 #endif 58 #include "redir.h" 59 #include "show.h" 60 #include "main.h" 61 #include "parser.h" 62 #include "nodes.h" 63 #include "jobs.h" 64 #include "options.h" 65 #include "trap.h" 66 #include "syntax.h" 67 #include "input.h" 68 #include "output.h" 69 #include "memalloc.h" 70 #include "error.h" 71 #include "mystring.h" 72 #include "var.h" 73 #include "builtins.h" 74 75 76 static struct job *jobtab; /* array of jobs */ 77 static int njobs; /* size of array */ 78 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 79 MKINIT struct job *bgjob = NULL; /* last background process */ 80 #if JOBS 81 static struct job *jobmru; /* most recently used job list */ 82 static pid_t initialpgrp; /* pgrp of shell on invocation */ 83 #endif 84 int in_waitcmd = 0; /* are we in waitcmd()? */ 85 int in_dowait = 0; /* are we in dowait()? */ 86 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 87 static int ttyfd = -1; 88 89 #if JOBS 90 static void restartjob(struct job *); 91 #endif 92 static void freejob(struct job *); 93 static struct job *getjob(char *); 94 static pid_t dowait(int, struct job *); 95 static pid_t waitproc(int, int *); 96 static void checkzombies(void); 97 static void cmdtxt(union node *); 98 static void cmdputs(const char *); 99 #if JOBS 100 static void setcurjob(struct job *); 101 static void deljob(struct job *); 102 static struct job *getcurjob(struct job *); 103 #endif 104 static void printjobcmd(struct job *); 105 static void showjob(struct job *, int); 106 107 108 /* 109 * Turn job control on and off. 110 */ 111 112 MKINIT int jobctl; 113 114 #if JOBS 115 void 116 setjobctl(int on) 117 { 118 int i; 119 120 if (on == jobctl || rootshell == 0) 121 return; 122 if (on) { 123 if (ttyfd != -1) 124 close(ttyfd); 125 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 126 i = 0; 127 while (i <= 2 && !isatty(i)) 128 i++; 129 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 130 goto out; 131 } 132 if (ttyfd < 10) { 133 /* 134 * Keep our TTY file descriptor out of the way of 135 * the user's redirections. 136 */ 137 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 138 close(ttyfd); 139 ttyfd = -1; 140 goto out; 141 } 142 close(ttyfd); 143 ttyfd = i; 144 } 145 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 146 close(ttyfd); 147 ttyfd = -1; 148 goto out; 149 } 150 do { /* while we are in the background */ 151 initialpgrp = tcgetpgrp(ttyfd); 152 if (initialpgrp < 0) { 153 out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 154 mflag = 0; 155 return; 156 } 157 if (initialpgrp != getpgrp()) { 158 kill(0, SIGTTIN); 159 continue; 160 } 161 } while (0); 162 setsignal(SIGTSTP); 163 setsignal(SIGTTOU); 164 setsignal(SIGTTIN); 165 setpgid(0, rootpid); 166 tcsetpgrp(ttyfd, rootpid); 167 } else { /* turning job control off */ 168 setpgid(0, initialpgrp); 169 tcsetpgrp(ttyfd, initialpgrp); 170 close(ttyfd); 171 ttyfd = -1; 172 setsignal(SIGTSTP); 173 setsignal(SIGTTOU); 174 setsignal(SIGTTIN); 175 } 176 jobctl = on; 177 } 178 #endif 179 180 181 #if JOBS 182 int 183 fgcmd(int argc __unused, char **argv) 184 { 185 struct job *jp; 186 pid_t pgrp; 187 int status; 188 189 jp = getjob(argv[1]); 190 if (jp->jobctl == 0) 191 error("job not created under job control"); 192 printjobcmd(jp); 193 flushout(&output); 194 pgrp = jp->ps[0].pid; 195 tcsetpgrp(ttyfd, pgrp); 196 restartjob(jp); 197 jp->foreground = 1; 198 INTOFF; 199 status = waitforjob(jp, NULL); 200 INTON; 201 return status; 202 } 203 204 205 int 206 bgcmd(int argc, char **argv) 207 { 208 struct job *jp; 209 210 do { 211 jp = getjob(*++argv); 212 if (jp->jobctl == 0) 213 error("job not created under job control"); 214 if (jp->state == JOBDONE) 215 continue; 216 restartjob(jp); 217 jp->foreground = 0; 218 out1fmt("[%td] ", jp - jobtab + 1); 219 printjobcmd(jp); 220 } while (--argc > 1); 221 return 0; 222 } 223 224 225 static void 226 restartjob(struct job *jp) 227 { 228 struct procstat *ps; 229 int i; 230 231 if (jp->state == JOBDONE) 232 return; 233 setcurjob(jp); 234 INTOFF; 235 kill(-jp->ps[0].pid, SIGCONT); 236 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 237 if (WIFSTOPPED(ps->status)) { 238 ps->status = -1; 239 jp->state = 0; 240 } 241 } 242 INTON; 243 } 244 #endif 245 246 247 int 248 jobscmd(int argc, char *argv[]) 249 { 250 char *id; 251 int ch, mode; 252 253 optind = optreset = 1; 254 opterr = 0; 255 mode = SHOWJOBS_DEFAULT; 256 while ((ch = getopt(argc, argv, "lps")) != -1) { 257 switch (ch) { 258 case 'l': 259 mode = SHOWJOBS_VERBOSE; 260 break; 261 case 'p': 262 mode = SHOWJOBS_PGIDS; 263 break; 264 case 's': 265 mode = SHOWJOBS_PIDS; 266 break; 267 case '?': 268 default: 269 error("unknown option: -%c", optopt); 270 } 271 } 272 argc -= optind; 273 argv += optind; 274 275 if (argc == 0) 276 showjobs(0, mode); 277 else 278 while ((id = *argv++) != NULL) 279 showjob(getjob(id), mode); 280 281 return (0); 282 } 283 284 static void 285 printjobcmd(struct job *jp) 286 { 287 struct procstat *ps; 288 int i; 289 290 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 291 out1str(ps->cmd); 292 if (i > 0) 293 out1str(" | "); 294 } 295 out1c('\n'); 296 } 297 298 static void 299 showjob(struct job *jp, int mode) 300 { 301 char s[64]; 302 char statestr[64]; 303 struct procstat *ps; 304 struct job *j; 305 int col, curr, i, jobno, prev, procno; 306 char c; 307 308 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 309 jobno = jp - jobtab + 1; 310 curr = prev = 0; 311 #if JOBS 312 if ((j = getcurjob(NULL)) != NULL) { 313 curr = j - jobtab + 1; 314 if ((j = getcurjob(j)) != NULL) 315 prev = j - jobtab + 1; 316 } 317 #endif 318 ps = jp->ps + jp->nprocs - 1; 319 if (jp->state == 0) { 320 strcpy(statestr, "Running"); 321 #if JOBS 322 } else if (jp->state == JOBSTOPPED) { 323 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 324 ps--; 325 if (WIFSTOPPED(ps->status)) 326 i = WSTOPSIG(ps->status); 327 else 328 i = -1; 329 if (i > 0 && i < sys_nsig && sys_siglist[i]) 330 strcpy(statestr, sys_siglist[i]); 331 else 332 strcpy(statestr, "Suspended"); 333 #endif 334 } else if (WIFEXITED(ps->status)) { 335 if (WEXITSTATUS(ps->status) == 0) 336 strcpy(statestr, "Done"); 337 else 338 fmtstr(statestr, 64, "Done(%d)", 339 WEXITSTATUS(ps->status)); 340 } else { 341 i = WTERMSIG(ps->status); 342 if (i > 0 && i < sys_nsig && sys_siglist[i]) 343 strcpy(statestr, sys_siglist[i]); 344 else 345 fmtstr(statestr, 64, "Signal %d", i); 346 if (WCOREDUMP(ps->status)) 347 strcat(statestr, " (core dumped)"); 348 } 349 350 for (ps = jp->ps ; ; ps++) { /* for each process */ 351 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 352 out1fmt("%d\n", (int)ps->pid); 353 goto skip; 354 } 355 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 356 goto skip; 357 if (jobno == curr && ps == jp->ps) 358 c = '+'; 359 else if (jobno == prev && ps == jp->ps) 360 c = '-'; 361 else 362 c = ' '; 363 if (ps == jp->ps) 364 fmtstr(s, 64, "[%d] %c ", jobno, c); 365 else 366 fmtstr(s, 64, " %c ", c); 367 out1str(s); 368 col = strlen(s); 369 if (mode == SHOWJOBS_VERBOSE) { 370 fmtstr(s, 64, "%d ", (int)ps->pid); 371 out1str(s); 372 col += strlen(s); 373 } 374 if (ps == jp->ps) { 375 out1str(statestr); 376 col += strlen(statestr); 377 } 378 do { 379 out1c(' '); 380 col++; 381 } while (col < 30); 382 if (mode == SHOWJOBS_VERBOSE) { 383 out1str(ps->cmd); 384 out1c('\n'); 385 } else 386 printjobcmd(jp); 387 skip: if (--procno <= 0) 388 break; 389 } 390 } 391 392 /* 393 * Print a list of jobs. If "change" is nonzero, only print jobs whose 394 * statuses have changed since the last call to showjobs. 395 * 396 * If the shell is interrupted in the process of creating a job, the 397 * result may be a job structure containing zero processes. Such structures 398 * will be freed here. 399 */ 400 401 void 402 showjobs(int change, int mode) 403 { 404 int jobno; 405 struct job *jp; 406 407 TRACE(("showjobs(%d) called\n", change)); 408 checkzombies(); 409 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 410 if (! jp->used) 411 continue; 412 if (jp->nprocs == 0) { 413 freejob(jp); 414 continue; 415 } 416 if (change && ! jp->changed) 417 continue; 418 showjob(jp, mode); 419 jp->changed = 0; 420 /* Hack: discard jobs for which $! has not been referenced 421 * in interactive mode when they terminate. 422 */ 423 if (jp->state == JOBDONE && !jp->remembered && 424 (iflag || jp != bgjob)) { 425 freejob(jp); 426 } 427 } 428 } 429 430 431 /* 432 * Mark a job structure as unused. 433 */ 434 435 static void 436 freejob(struct job *jp) 437 { 438 struct procstat *ps; 439 int i; 440 441 INTOFF; 442 if (bgjob == jp) 443 bgjob = NULL; 444 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 445 if (ps->cmd != nullstr) 446 ckfree(ps->cmd); 447 } 448 if (jp->ps != &jp->ps0) 449 ckfree(jp->ps); 450 jp->used = 0; 451 #if JOBS 452 deljob(jp); 453 #endif 454 INTON; 455 } 456 457 458 459 int 460 waitcmd(int argc, char **argv) 461 { 462 struct job *job; 463 int status, retval; 464 struct job *jp; 465 466 if (argc > 1) { 467 job = getjob(argv[1]); 468 } else { 469 job = NULL; 470 } 471 472 /* 473 * Loop until a process is terminated or stopped, or a SIGINT is 474 * received. 475 */ 476 477 in_waitcmd++; 478 do { 479 if (job != NULL) { 480 if (job->state) { 481 status = job->ps[job->nprocs - 1].status; 482 if (WIFEXITED(status)) 483 retval = WEXITSTATUS(status); 484 #if JOBS 485 else if (WIFSTOPPED(status)) 486 retval = WSTOPSIG(status) + 128; 487 #endif 488 else 489 retval = WTERMSIG(status) + 128; 490 if (! iflag || ! job->changed) 491 freejob(job); 492 else { 493 job->remembered = 0; 494 if (job == bgjob) 495 bgjob = NULL; 496 } 497 in_waitcmd--; 498 return retval; 499 } 500 } else { 501 for (jp = jobtab ; jp < jobtab + njobs; jp++) 502 if (jp->used && jp->state == JOBDONE) { 503 if (! iflag || ! jp->changed) 504 freejob(jp); 505 else { 506 jp->remembered = 0; 507 if (jp == bgjob) 508 bgjob = NULL; 509 } 510 } 511 for (jp = jobtab ; ; jp++) { 512 if (jp >= jobtab + njobs) { /* no running procs */ 513 in_waitcmd--; 514 return 0; 515 } 516 if (jp->used && jp->state == 0) 517 break; 518 } 519 } 520 } while (dowait(1, NULL) != -1); 521 in_waitcmd--; 522 523 return 0; 524 } 525 526 527 528 int 529 jobidcmd(int argc __unused, char **argv) 530 { 531 struct job *jp; 532 int i; 533 534 jp = getjob(argv[1]); 535 for (i = 0 ; i < jp->nprocs ; ) { 536 out1fmt("%d", (int)jp->ps[i].pid); 537 out1c(++i < jp->nprocs? ' ' : '\n'); 538 } 539 return 0; 540 } 541 542 543 544 /* 545 * Convert a job name to a job structure. 546 */ 547 548 static struct job * 549 getjob(char *name) 550 { 551 int jobno; 552 struct job *found, *jp; 553 pid_t pid; 554 int i; 555 556 if (name == NULL) { 557 #if JOBS 558 currentjob: if ((jp = getcurjob(NULL)) == NULL) 559 error("No current job"); 560 return (jp); 561 #else 562 error("No current job"); 563 #endif 564 } else if (name[0] == '%') { 565 if (is_digit(name[1])) { 566 jobno = number(name + 1); 567 if (jobno > 0 && jobno <= njobs 568 && jobtab[jobno - 1].used != 0) 569 return &jobtab[jobno - 1]; 570 #if JOBS 571 } else if (name[1] == '%' && name[2] == '\0') { 572 goto currentjob; 573 } else if (name[1] == '+' && name[2] == '\0') { 574 goto currentjob; 575 } else if (name[1] == '-' && name[2] == '\0') { 576 if ((jp = getcurjob(NULL)) == NULL || 577 (jp = getcurjob(jp)) == NULL) 578 error("No previous job"); 579 return (jp); 580 #endif 581 } else if (name[1] == '?') { 582 found = NULL; 583 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 584 if (jp->used && jp->nprocs > 0 585 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 586 if (found) 587 error("%s: ambiguous", name); 588 found = jp; 589 } 590 } 591 if (found != NULL) 592 return (found); 593 } else { 594 found = NULL; 595 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 596 if (jp->used && jp->nprocs > 0 597 && prefix(name + 1, jp->ps[0].cmd)) { 598 if (found) 599 error("%s: ambiguous", name); 600 found = jp; 601 } 602 } 603 if (found) 604 return found; 605 } 606 } else if (is_number(name)) { 607 pid = (pid_t)number(name); 608 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 609 if (jp->used && jp->nprocs > 0 610 && jp->ps[jp->nprocs - 1].pid == pid) 611 return jp; 612 } 613 } 614 error("No such job: %s", name); 615 /*NOTREACHED*/ 616 return NULL; 617 } 618 619 620 pid_t 621 getjobpgrp(char *name) 622 { 623 struct job *jp; 624 625 jp = getjob(name); 626 return -jp->ps[0].pid; 627 } 628 629 /* 630 * Return a new job structure, 631 */ 632 633 struct job * 634 makejob(union node *node __unused, int nprocs) 635 { 636 int i; 637 struct job *jp; 638 639 for (i = njobs, jp = jobtab ; ; jp++) { 640 if (--i < 0) { 641 INTOFF; 642 if (njobs == 0) { 643 jobtab = ckmalloc(4 * sizeof jobtab[0]); 644 #if JOBS 645 jobmru = NULL; 646 #endif 647 } else { 648 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 649 memcpy(jp, jobtab, njobs * sizeof jp[0]); 650 #if JOBS 651 /* Relocate `next' pointers and list head */ 652 if (jobmru != NULL) 653 jobmru = &jp[jobmru - jobtab]; 654 for (i = 0; i < njobs; i++) 655 if (jp[i].next != NULL) 656 jp[i].next = &jp[jp[i].next - 657 jobtab]; 658 #endif 659 if (bgjob != NULL) 660 bgjob = &jp[bgjob - jobtab]; 661 /* Relocate `ps' pointers */ 662 for (i = 0; i < njobs; i++) 663 if (jp[i].ps == &jobtab[i].ps0) 664 jp[i].ps = &jp[i].ps0; 665 ckfree(jobtab); 666 jobtab = jp; 667 } 668 jp = jobtab + njobs; 669 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 670 INTON; 671 break; 672 } 673 if (jp->used == 0) 674 break; 675 } 676 INTOFF; 677 jp->state = 0; 678 jp->used = 1; 679 jp->changed = 0; 680 jp->nprocs = 0; 681 jp->foreground = 0; 682 jp->remembered = 0; 683 #if JOBS 684 jp->jobctl = jobctl; 685 jp->next = NULL; 686 #endif 687 if (nprocs > 1) { 688 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 689 } else { 690 jp->ps = &jp->ps0; 691 } 692 INTON; 693 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 694 jp - jobtab + 1)); 695 return jp; 696 } 697 698 #if JOBS 699 static void 700 setcurjob(struct job *cj) 701 { 702 struct job *jp, *prev; 703 704 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 705 if (jp == cj) { 706 if (prev != NULL) 707 prev->next = jp->next; 708 else 709 jobmru = jp->next; 710 jp->next = jobmru; 711 jobmru = cj; 712 return; 713 } 714 } 715 cj->next = jobmru; 716 jobmru = cj; 717 } 718 719 static void 720 deljob(struct job *j) 721 { 722 struct job *jp, *prev; 723 724 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 725 if (jp == j) { 726 if (prev != NULL) 727 prev->next = jp->next; 728 else 729 jobmru = jp->next; 730 return; 731 } 732 } 733 } 734 735 /* 736 * Return the most recently used job that isn't `nj', and preferably one 737 * that is stopped. 738 */ 739 static struct job * 740 getcurjob(struct job *nj) 741 { 742 struct job *jp; 743 744 /* Try to find a stopped one.. */ 745 for (jp = jobmru; jp != NULL; jp = jp->next) 746 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 747 return (jp); 748 /* Otherwise the most recently used job that isn't `nj' */ 749 for (jp = jobmru; jp != NULL; jp = jp->next) 750 if (jp->used && jp != nj) 751 return (jp); 752 753 return (NULL); 754 } 755 756 #endif 757 758 /* 759 * Fork of a subshell. If we are doing job control, give the subshell its 760 * own process group. Jp is a job structure that the job is to be added to. 761 * N is the command that will be evaluated by the child. Both jp and n may 762 * be NULL. The mode parameter can be one of the following: 763 * FORK_FG - Fork off a foreground process. 764 * FORK_BG - Fork off a background process. 765 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 766 * process group even if job control is on. 767 * 768 * When job control is turned off, background processes have their standard 769 * input redirected to /dev/null (except for the second and later processes 770 * in a pipeline). 771 */ 772 773 pid_t 774 forkshell(struct job *jp, union node *n, int mode) 775 { 776 pid_t pid; 777 pid_t pgrp; 778 779 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 780 mode)); 781 INTOFF; 782 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 783 checkzombies(); 784 flushall(); 785 pid = fork(); 786 if (pid == -1) { 787 TRACE(("Fork failed, errno=%d\n", errno)); 788 INTON; 789 error("Cannot fork: %s", strerror(errno)); 790 } 791 if (pid == 0) { 792 struct job *p; 793 int wasroot; 794 int i; 795 796 TRACE(("Child shell %d\n", (int)getpid())); 797 wasroot = rootshell; 798 rootshell = 0; 799 handler = &main_handler; 800 closescript(); 801 INTON; 802 forcelocal = 0; 803 clear_traps(); 804 #if JOBS 805 jobctl = 0; /* do job control only in root shell */ 806 if (wasroot && mode != FORK_NOJOB && mflag) { 807 if (jp == NULL || jp->nprocs == 0) 808 pgrp = getpid(); 809 else 810 pgrp = jp->ps[0].pid; 811 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 812 /*** this causes superfluous TIOCSPGRPS ***/ 813 if (tcsetpgrp(ttyfd, pgrp) < 0) 814 error("tcsetpgrp failed, errno=%d", errno); 815 } 816 setsignal(SIGTSTP); 817 setsignal(SIGTTOU); 818 } else if (mode == FORK_BG) { 819 ignoresig(SIGINT); 820 ignoresig(SIGQUIT); 821 if ((jp == NULL || jp->nprocs == 0) && 822 ! fd0_redirected_p ()) { 823 close(0); 824 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 825 error("cannot open %s: %s", 826 _PATH_DEVNULL, strerror(errno)); 827 } 828 } 829 #else 830 if (mode == FORK_BG) { 831 ignoresig(SIGINT); 832 ignoresig(SIGQUIT); 833 if ((jp == NULL || jp->nprocs == 0) && 834 ! fd0_redirected_p ()) { 835 close(0); 836 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 837 error("cannot open %s: %s", 838 _PATH_DEVNULL, strerror(errno)); 839 } 840 } 841 #endif 842 INTOFF; 843 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 844 if (p->used) 845 freejob(p); 846 INTON; 847 if (wasroot && iflag) { 848 setsignal(SIGINT); 849 setsignal(SIGQUIT); 850 setsignal(SIGTERM); 851 } 852 return pid; 853 } 854 if (rootshell && mode != FORK_NOJOB && mflag) { 855 if (jp == NULL || jp->nprocs == 0) 856 pgrp = pid; 857 else 858 pgrp = jp->ps[0].pid; 859 setpgid(pid, pgrp); 860 } 861 if (mode == FORK_BG) { 862 if (bgjob != NULL && bgjob->state == JOBDONE && 863 !bgjob->remembered && !iflag) 864 freejob(bgjob); 865 backgndpid = pid; /* set $! */ 866 bgjob = jp; 867 } 868 if (jp) { 869 struct procstat *ps = &jp->ps[jp->nprocs++]; 870 ps->pid = pid; 871 ps->status = -1; 872 ps->cmd = nullstr; 873 if (iflag && rootshell && n) 874 ps->cmd = commandtext(n); 875 jp->foreground = mode == FORK_FG; 876 #if JOBS 877 setcurjob(jp); 878 #endif 879 } 880 INTON; 881 TRACE(("In parent shell: child = %d\n", (int)pid)); 882 return pid; 883 } 884 885 886 887 /* 888 * Wait for job to finish. 889 * 890 * Under job control we have the problem that while a child process is 891 * running interrupts generated by the user are sent to the child but not 892 * to the shell. This means that an infinite loop started by an inter- 893 * active user may be hard to kill. With job control turned off, an 894 * interactive user may place an interactive program inside a loop. If 895 * the interactive program catches interrupts, the user doesn't want 896 * these interrupts to also abort the loop. The approach we take here 897 * is to have the shell ignore interrupt signals while waiting for a 898 * foreground process to terminate, and then send itself an interrupt 899 * signal if the child process was terminated by an interrupt signal. 900 * Unfortunately, some programs want to do a bit of cleanup and then 901 * exit on interrupt; unless these processes terminate themselves by 902 * sending a signal to themselves (instead of calling exit) they will 903 * confuse this approach. 904 */ 905 906 int 907 waitforjob(struct job *jp, int *origstatus) 908 { 909 #if JOBS 910 pid_t mypgrp = getpgrp(); 911 int propagate_int = jp->jobctl && jp->foreground; 912 #endif 913 int status; 914 int st; 915 916 INTOFF; 917 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 918 while (jp->state == 0) 919 if (dowait(1, jp) == -1) 920 dotrap(); 921 #if JOBS 922 if (jp->jobctl) { 923 if (tcsetpgrp(ttyfd, mypgrp) < 0) 924 error("tcsetpgrp failed, errno=%d\n", errno); 925 } 926 if (jp->state == JOBSTOPPED) 927 setcurjob(jp); 928 #endif 929 status = jp->ps[jp->nprocs - 1].status; 930 if (origstatus != NULL) 931 *origstatus = status; 932 /* convert to 8 bits */ 933 if (WIFEXITED(status)) 934 st = WEXITSTATUS(status); 935 #if JOBS 936 else if (WIFSTOPPED(status)) 937 st = WSTOPSIG(status) + 128; 938 #endif 939 else 940 st = WTERMSIG(status) + 128; 941 if (! JOBS || jp->state == JOBDONE) 942 freejob(jp); 943 if (int_pending()) { 944 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 945 CLEAR_PENDING_INT; 946 } 947 #if JOBS 948 else if (rootshell && iflag && propagate_int && 949 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 950 kill(getpid(), SIGINT); 951 #endif 952 INTON; 953 return st; 954 } 955 956 957 958 /* 959 * Wait for a process to terminate. 960 */ 961 962 static pid_t 963 dowait(int block, struct job *job) 964 { 965 pid_t pid; 966 int status; 967 struct procstat *sp; 968 struct job *jp; 969 struct job *thisjob; 970 int done; 971 int stopped; 972 int sig; 973 int coredump; 974 975 in_dowait++; 976 TRACE(("dowait(%d) called\n", block)); 977 do { 978 pid = waitproc(block, &status); 979 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 980 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 981 (pid > 0 && WIFSTOPPED(status) && !iflag)); 982 in_dowait--; 983 if (pid == -1 && errno == ECHILD && job != NULL) 984 job->state = JOBDONE; 985 if (breakwaitcmd != 0) { 986 breakwaitcmd = 0; 987 /* 988 * Do not early terminate if the pid is positive, else the 989 * job will not be properly recorded. 990 */ 991 if (pid <= 0) 992 return -1; 993 } 994 if (pid <= 0) 995 return pid; 996 INTOFF; 997 thisjob = NULL; 998 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 999 if (jp->used && jp->nprocs > 0) { 1000 done = 1; 1001 stopped = 1; 1002 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1003 if (sp->pid == -1) 1004 continue; 1005 if (sp->pid == pid) { 1006 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1007 (int)pid, sp->status, 1008 status)); 1009 sp->status = status; 1010 thisjob = jp; 1011 } 1012 if (sp->status == -1) 1013 stopped = 0; 1014 else if (WIFSTOPPED(sp->status)) 1015 done = 0; 1016 } 1017 if (stopped) { /* stopped or done */ 1018 int state = done? JOBDONE : JOBSTOPPED; 1019 if (jp->state != state) { 1020 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1021 jp->state = state; 1022 if (jp != job) { 1023 if (done && !jp->remembered && 1024 !iflag && jp != bgjob) 1025 freejob(jp); 1026 #if JOBS 1027 else if (done) 1028 deljob(jp); 1029 #endif 1030 } 1031 } 1032 } 1033 } 1034 } 1035 INTON; 1036 if (!thisjob || thisjob->state == 0) 1037 ; 1038 else if ((!rootshell || !iflag || thisjob == job) && 1039 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1040 sig = 0; 1041 coredump = 0; 1042 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1043 if (WIFSIGNALED(sp->status)) { 1044 sig = WTERMSIG(sp->status); 1045 coredump = WCOREDUMP(sp->status); 1046 } 1047 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1048 if (sig < sys_nsig && sys_siglist[sig]) 1049 out2str(sys_siglist[sig]); 1050 else 1051 outfmt(out2, "Signal %d", sig); 1052 if (coredump) 1053 out2str(" (core dumped)"); 1054 out2c('\n'); 1055 flushout(out2); 1056 } 1057 } else { 1058 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1059 thisjob->changed = 1; 1060 } 1061 return pid; 1062 } 1063 1064 1065 1066 /* 1067 * Do a wait system call. If job control is compiled in, we accept 1068 * stopped processes. If block is zero, we return a value of zero 1069 * rather than blocking. 1070 */ 1071 static pid_t 1072 waitproc(int block, int *status) 1073 { 1074 int flags; 1075 1076 #if JOBS 1077 flags = WUNTRACED; 1078 #else 1079 flags = 0; 1080 #endif 1081 if (block == 0) 1082 flags |= WNOHANG; 1083 return wait3(status, flags, NULL); 1084 } 1085 1086 /* 1087 * return 1 if there are stopped jobs, otherwise 0 1088 */ 1089 int job_warning = 0; 1090 int 1091 stoppedjobs(void) 1092 { 1093 int jobno; 1094 struct job *jp; 1095 1096 if (job_warning) 1097 return (0); 1098 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1099 if (jp->used == 0) 1100 continue; 1101 if (jp->state == JOBSTOPPED) { 1102 out2fmt_flush("You have stopped jobs.\n"); 1103 job_warning = 2; 1104 return (1); 1105 } 1106 } 1107 1108 return (0); 1109 } 1110 1111 1112 static void 1113 checkzombies(void) 1114 { 1115 while (njobs > 0 && dowait(0, NULL) > 0) 1116 ; 1117 } 1118 1119 1120 int 1121 backgndpidset(void) 1122 { 1123 return backgndpid != -1; 1124 } 1125 1126 1127 pid_t 1128 backgndpidval(void) 1129 { 1130 if (bgjob != NULL && !forcelocal) 1131 bgjob->remembered = 1; 1132 return backgndpid; 1133 } 1134 1135 /* 1136 * Return a string identifying a command (to be printed by the 1137 * jobs command. 1138 */ 1139 1140 static char *cmdnextc; 1141 static int cmdnleft; 1142 #define MAXCMDTEXT 200 1143 1144 char * 1145 commandtext(union node *n) 1146 { 1147 char *name; 1148 1149 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1150 cmdnleft = MAXCMDTEXT - 4; 1151 cmdtxt(n); 1152 *cmdnextc = '\0'; 1153 return name; 1154 } 1155 1156 1157 static void 1158 cmdtxt(union node *n) 1159 { 1160 union node *np; 1161 struct nodelist *lp; 1162 const char *p; 1163 int i; 1164 char s[2]; 1165 1166 if (n == NULL) 1167 return; 1168 switch (n->type) { 1169 case NSEMI: 1170 cmdtxt(n->nbinary.ch1); 1171 cmdputs("; "); 1172 cmdtxt(n->nbinary.ch2); 1173 break; 1174 case NAND: 1175 cmdtxt(n->nbinary.ch1); 1176 cmdputs(" && "); 1177 cmdtxt(n->nbinary.ch2); 1178 break; 1179 case NOR: 1180 cmdtxt(n->nbinary.ch1); 1181 cmdputs(" || "); 1182 cmdtxt(n->nbinary.ch2); 1183 break; 1184 case NPIPE: 1185 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1186 cmdtxt(lp->n); 1187 if (lp->next) 1188 cmdputs(" | "); 1189 } 1190 break; 1191 case NSUBSHELL: 1192 cmdputs("("); 1193 cmdtxt(n->nredir.n); 1194 cmdputs(")"); 1195 break; 1196 case NREDIR: 1197 case NBACKGND: 1198 cmdtxt(n->nredir.n); 1199 break; 1200 case NIF: 1201 cmdputs("if "); 1202 cmdtxt(n->nif.test); 1203 cmdputs("; then "); 1204 cmdtxt(n->nif.ifpart); 1205 cmdputs("..."); 1206 break; 1207 case NWHILE: 1208 cmdputs("while "); 1209 goto until; 1210 case NUNTIL: 1211 cmdputs("until "); 1212 until: 1213 cmdtxt(n->nbinary.ch1); 1214 cmdputs("; do "); 1215 cmdtxt(n->nbinary.ch2); 1216 cmdputs("; done"); 1217 break; 1218 case NFOR: 1219 cmdputs("for "); 1220 cmdputs(n->nfor.var); 1221 cmdputs(" in ..."); 1222 break; 1223 case NCASE: 1224 cmdputs("case "); 1225 cmdputs(n->ncase.expr->narg.text); 1226 cmdputs(" in ..."); 1227 break; 1228 case NDEFUN: 1229 cmdputs(n->narg.text); 1230 cmdputs("() ..."); 1231 break; 1232 case NCMD: 1233 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1234 cmdtxt(np); 1235 if (np->narg.next) 1236 cmdputs(" "); 1237 } 1238 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1239 cmdputs(" "); 1240 cmdtxt(np); 1241 } 1242 break; 1243 case NARG: 1244 cmdputs(n->narg.text); 1245 break; 1246 case NTO: 1247 p = ">"; i = 1; goto redir; 1248 case NAPPEND: 1249 p = ">>"; i = 1; goto redir; 1250 case NTOFD: 1251 p = ">&"; i = 1; goto redir; 1252 case NCLOBBER: 1253 p = ">|"; i = 1; goto redir; 1254 case NFROM: 1255 p = "<"; i = 0; goto redir; 1256 case NFROMTO: 1257 p = "<>"; i = 0; goto redir; 1258 case NFROMFD: 1259 p = "<&"; i = 0; goto redir; 1260 redir: 1261 if (n->nfile.fd != i) { 1262 s[0] = n->nfile.fd + '0'; 1263 s[1] = '\0'; 1264 cmdputs(s); 1265 } 1266 cmdputs(p); 1267 if (n->type == NTOFD || n->type == NFROMFD) { 1268 if (n->ndup.dupfd >= 0) 1269 s[0] = n->ndup.dupfd + '0'; 1270 else 1271 s[0] = '-'; 1272 s[1] = '\0'; 1273 cmdputs(s); 1274 } else { 1275 cmdtxt(n->nfile.fname); 1276 } 1277 break; 1278 case NHERE: 1279 case NXHERE: 1280 cmdputs("<<..."); 1281 break; 1282 default: 1283 cmdputs("???"); 1284 break; 1285 } 1286 } 1287 1288 1289 1290 static void 1291 cmdputs(const char *s) 1292 { 1293 const char *p; 1294 char *q; 1295 char c; 1296 int subtype = 0; 1297 1298 if (cmdnleft <= 0) 1299 return; 1300 p = s; 1301 q = cmdnextc; 1302 while ((c = *p++) != '\0') { 1303 if (c == CTLESC) 1304 *q++ = *p++; 1305 else if (c == CTLVAR) { 1306 *q++ = '$'; 1307 if (--cmdnleft > 0) 1308 *q++ = '{'; 1309 subtype = *p++; 1310 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1311 *q++ = '#'; 1312 } else if (c == '=' && subtype != 0) { 1313 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1314 if (*q) 1315 q++; 1316 else 1317 cmdnleft++; 1318 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1319 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1320 --cmdnleft > 0) 1321 *q = q[-1], q++; 1322 subtype = 0; 1323 } else if (c == CTLENDVAR) { 1324 *q++ = '}'; 1325 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1326 cmdnleft -= 5; 1327 if (cmdnleft > 0) { 1328 *q++ = '$'; 1329 *q++ = '('; 1330 *q++ = '.'; 1331 *q++ = '.'; 1332 *q++ = '.'; 1333 *q++ = ')'; 1334 } 1335 } else if (c == CTLARI) { 1336 cmdnleft -= 2; 1337 if (cmdnleft > 0) { 1338 *q++ = '$'; 1339 *q++ = '('; 1340 *q++ = '('; 1341 } 1342 p++; 1343 } else if (c == CTLENDARI) { 1344 if (--cmdnleft > 0) { 1345 *q++ = ')'; 1346 *q++ = ')'; 1347 } 1348 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1349 cmdnleft++; /* ignore */ 1350 else 1351 *q++ = c; 1352 if (--cmdnleft <= 0) { 1353 *q++ = '.'; 1354 *q++ = '.'; 1355 *q++ = '.'; 1356 break; 1357 } 1358 } 1359 cmdnextc = q; 1360 } 1361