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 1.92 2011/02/04 22:47:55 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 73 74 static struct job *jobtab; /* array of jobs */ 75 static int njobs; /* size of array */ 76 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 77 MKINIT struct job *bgjob = NULL; /* 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 checkzombies(void); 95 static void cmdtxt(union node *); 96 static void cmdputs(const char *); 97 #if JOBS 98 static void setcurjob(struct job *); 99 static void deljob(struct job *); 100 static struct job *getcurjob(struct job *); 101 #endif 102 static void printjobcmd(struct job *); 103 static void showjob(struct job *, int); 104 105 106 /* 107 * Turn job control on and off. 108 */ 109 110 MKINIT int jobctl; 111 112 #if JOBS 113 void 114 setjobctl(int on) 115 { 116 int i; 117 118 if (on == jobctl || rootshell == 0) 119 return; 120 if (on) { 121 if (ttyfd != -1) 122 close(ttyfd); 123 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 124 i = 0; 125 while (i <= 2 && !isatty(i)) 126 i++; 127 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 128 goto out; 129 } 130 if (ttyfd < 10) { 131 /* 132 * Keep our TTY file descriptor out of the way of 133 * the user's redirections. 134 */ 135 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 136 close(ttyfd); 137 ttyfd = -1; 138 goto out; 139 } 140 close(ttyfd); 141 ttyfd = i; 142 } 143 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 144 close(ttyfd); 145 ttyfd = -1; 146 goto out; 147 } 148 do { /* while we are in the background */ 149 initialpgrp = tcgetpgrp(ttyfd); 150 if (initialpgrp < 0) { 151 out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 152 mflag = 0; 153 return; 154 } 155 if (initialpgrp != getpgrp()) { 156 kill(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 #if JOBS 180 int 181 fgcmd(int argc __unused, char **argv) 182 { 183 struct job *jp; 184 pid_t pgrp; 185 int status; 186 187 jp = getjob(argv[1]); 188 if (jp->jobctl == 0) 189 error("job not created under job control"); 190 printjobcmd(jp); 191 flushout(&output); 192 pgrp = jp->ps[0].pid; 193 tcsetpgrp(ttyfd, pgrp); 194 restartjob(jp); 195 jp->foreground = 1; 196 INTOFF; 197 status = waitforjob(jp, NULL); 198 INTON; 199 return status; 200 } 201 202 203 int 204 bgcmd(int argc, char **argv) 205 { 206 struct job *jp; 207 208 do { 209 jp = getjob(*++argv); 210 if (jp->jobctl == 0) 211 error("job not created under job control"); 212 if (jp->state == JOBDONE) 213 continue; 214 restartjob(jp); 215 jp->foreground = 0; 216 out1fmt("[%td] ", jp - jobtab + 1); 217 printjobcmd(jp); 218 } while (--argc > 1); 219 return 0; 220 } 221 222 223 static void 224 restartjob(struct job *jp) 225 { 226 struct procstat *ps; 227 int i; 228 229 if (jp->state == JOBDONE) 230 return; 231 setcurjob(jp); 232 INTOFF; 233 kill(-jp->ps[0].pid, SIGCONT); 234 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 235 if (WIFSTOPPED(ps->status)) { 236 ps->status = -1; 237 jp->state = 0; 238 } 239 } 240 INTON; 241 } 242 #endif 243 244 245 int 246 jobscmd(int argc, char *argv[]) 247 { 248 char *id; 249 int ch, mode; 250 251 optind = optreset = 1; 252 opterr = 0; 253 mode = SHOWJOBS_DEFAULT; 254 while ((ch = getopt(argc, argv, "lps")) != -1) { 255 switch (ch) { 256 case 'l': 257 mode = SHOWJOBS_VERBOSE; 258 break; 259 case 'p': 260 mode = SHOWJOBS_PGIDS; 261 break; 262 case 's': 263 mode = SHOWJOBS_PIDS; 264 break; 265 case '?': 266 default: 267 error("unknown option: -%c", optopt); 268 } 269 } 270 argc -= optind; 271 argv += optind; 272 273 if (argc == 0) 274 showjobs(0, mode); 275 else 276 while ((id = *argv++) != NULL) 277 showjob(getjob(id), mode); 278 279 return (0); 280 } 281 282 static void 283 printjobcmd(struct job *jp) 284 { 285 struct procstat *ps; 286 int i; 287 288 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 289 out1str(ps->cmd); 290 if (i > 0) 291 out1str(" | "); 292 } 293 out1c('\n'); 294 } 295 296 static void 297 showjob(struct job *jp, int mode) 298 { 299 char s[64]; 300 char statestr[64]; 301 struct procstat *ps; 302 struct job *j; 303 int col, curr, i, jobno, prev, procno; 304 char c; 305 306 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 307 jobno = jp - jobtab + 1; 308 curr = prev = 0; 309 #if JOBS 310 if ((j = getcurjob(NULL)) != NULL) { 311 curr = j - jobtab + 1; 312 if ((j = getcurjob(j)) != NULL) 313 prev = j - jobtab + 1; 314 } 315 #endif 316 ps = jp->ps + jp->nprocs - 1; 317 if (jp->state == 0) { 318 strcpy(statestr, "Running"); 319 #if JOBS 320 } else if (jp->state == JOBSTOPPED) { 321 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 322 ps--; 323 if (WIFSTOPPED(ps->status)) 324 i = WSTOPSIG(ps->status); 325 else 326 i = -1; 327 if (i > 0 && i < sys_nsig && sys_siglist[i]) 328 strcpy(statestr, sys_siglist[i]); 329 else 330 strcpy(statestr, "Suspended"); 331 #endif 332 } else if (WIFEXITED(ps->status)) { 333 if (WEXITSTATUS(ps->status) == 0) 334 strcpy(statestr, "Done"); 335 else 336 fmtstr(statestr, 64, "Done(%d)", 337 WEXITSTATUS(ps->status)); 338 } else { 339 i = WTERMSIG(ps->status); 340 if (i > 0 && i < sys_nsig && sys_siglist[i]) 341 strcpy(statestr, sys_siglist[i]); 342 else 343 fmtstr(statestr, 64, "Signal %d", i); 344 if (WCOREDUMP(ps->status)) 345 strcat(statestr, " (core dumped)"); 346 } 347 348 for (ps = jp->ps ; ; ps++) { /* for each process */ 349 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 350 out1fmt("%d\n", (int)ps->pid); 351 goto skip; 352 } 353 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 354 goto skip; 355 if (jobno == curr && ps == jp->ps) 356 c = '+'; 357 else if (jobno == prev && ps == jp->ps) 358 c = '-'; 359 else 360 c = ' '; 361 if (ps == jp->ps) 362 fmtstr(s, 64, "[%d] %c ", jobno, c); 363 else 364 fmtstr(s, 64, " %c ", c); 365 out1str(s); 366 col = strlen(s); 367 if (mode == SHOWJOBS_VERBOSE) { 368 fmtstr(s, 64, "%d ", (int)ps->pid); 369 out1str(s); 370 col += strlen(s); 371 } 372 if (ps == jp->ps) { 373 out1str(statestr); 374 col += strlen(statestr); 375 } 376 do { 377 out1c(' '); 378 col++; 379 } while (col < 30); 380 if (mode == SHOWJOBS_VERBOSE) { 381 out1str(ps->cmd); 382 out1c('\n'); 383 } else 384 printjobcmd(jp); 385 skip: if (--procno <= 0) 386 break; 387 } 388 } 389 390 /* 391 * Print a list of jobs. If "change" is nonzero, only print jobs whose 392 * statuses have changed since the last call to showjobs. 393 * 394 * If the shell is interrupted in the process of creating a job, the 395 * result may be a job structure containing zero processes. Such structures 396 * will be freed here. 397 */ 398 399 void 400 showjobs(int change, int mode) 401 { 402 int jobno; 403 struct job *jp; 404 405 TRACE(("showjobs(%d) called\n", change)); 406 checkzombies(); 407 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 408 if (! jp->used) 409 continue; 410 if (jp->nprocs == 0) { 411 freejob(jp); 412 continue; 413 } 414 if (change && ! jp->changed) 415 continue; 416 showjob(jp, mode); 417 jp->changed = 0; 418 /* Hack: discard jobs for which $! has not been referenced 419 * in interactive mode when they terminate. 420 */ 421 if (jp->state == JOBDONE && !jp->remembered && 422 (iflag || jp != bgjob)) { 423 freejob(jp); 424 } 425 } 426 } 427 428 429 /* 430 * Mark a job structure as unused. 431 */ 432 433 static void 434 freejob(struct job *jp) 435 { 436 struct procstat *ps; 437 int i; 438 439 INTOFF; 440 if (bgjob == jp) 441 bgjob = NULL; 442 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 443 if (ps->cmd != nullstr) 444 ckfree(ps->cmd); 445 } 446 if (jp->ps != &jp->ps0) 447 ckfree(jp->ps); 448 jp->used = 0; 449 #if JOBS 450 deljob(jp); 451 #endif 452 INTON; 453 } 454 455 456 457 int 458 waitcmd(int argc, char **argv) 459 { 460 struct job *job; 461 int status, retval; 462 struct job *jp; 463 464 if (argc > 1) { 465 job = getjob(argv[1]); 466 } else { 467 job = NULL; 468 } 469 470 /* 471 * Loop until a process is terminated or stopped, or a SIGINT is 472 * received. 473 */ 474 475 in_waitcmd++; 476 do { 477 if (job != NULL) { 478 if (job->state) { 479 status = job->ps[job->nprocs - 1].status; 480 if (WIFEXITED(status)) 481 retval = WEXITSTATUS(status); 482 #if JOBS 483 else if (WIFSTOPPED(status)) 484 retval = WSTOPSIG(status) + 128; 485 #endif 486 else 487 retval = WTERMSIG(status) + 128; 488 if (! iflag || ! job->changed) 489 freejob(job); 490 else { 491 job->remembered = 0; 492 if (job == bgjob) 493 bgjob = NULL; 494 } 495 in_waitcmd--; 496 return retval; 497 } 498 } else { 499 for (jp = jobtab ; jp < jobtab + njobs; jp++) 500 if (jp->used && jp->state == JOBDONE) { 501 if (! iflag || ! jp->changed) 502 freejob(jp); 503 else { 504 jp->remembered = 0; 505 if (jp == bgjob) 506 bgjob = NULL; 507 } 508 } 509 for (jp = jobtab ; ; jp++) { 510 if (jp >= jobtab + njobs) { /* no running procs */ 511 in_waitcmd--; 512 return 0; 513 } 514 if (jp->used && jp->state == 0) 515 break; 516 } 517 } 518 } while (dowait(1, NULL) != -1); 519 in_waitcmd--; 520 521 return 0; 522 } 523 524 525 526 int 527 jobidcmd(int argc __unused, char **argv) 528 { 529 struct job *jp; 530 int i; 531 532 jp = getjob(argv[1]); 533 for (i = 0 ; i < jp->nprocs ; ) { 534 out1fmt("%d", (int)jp->ps[i].pid); 535 out1c(++i < jp->nprocs? ' ' : '\n'); 536 } 537 return 0; 538 } 539 540 541 542 /* 543 * Convert a job name to a job structure. 544 */ 545 546 static struct job * 547 getjob(char *name) 548 { 549 int jobno; 550 struct job *found, *jp; 551 pid_t pid; 552 int i; 553 554 if (name == NULL) { 555 #if JOBS 556 currentjob: if ((jp = getcurjob(NULL)) == NULL) 557 error("No current job"); 558 return (jp); 559 #else 560 error("No current job"); 561 #endif 562 } else if (name[0] == '%') { 563 if (is_digit(name[1])) { 564 jobno = number(name + 1); 565 if (jobno > 0 && jobno <= njobs 566 && jobtab[jobno - 1].used != 0) 567 return &jobtab[jobno - 1]; 568 #if JOBS 569 } else if (name[1] == '%' && name[2] == '\0') { 570 goto currentjob; 571 } else if (name[1] == '+' && name[2] == '\0') { 572 goto currentjob; 573 } else if (name[1] == '-' && name[2] == '\0') { 574 if ((jp = getcurjob(NULL)) == NULL || 575 (jp = getcurjob(jp)) == NULL) 576 error("No previous job"); 577 return (jp); 578 #endif 579 } else if (name[1] == '?') { 580 found = NULL; 581 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 582 if (jp->used && jp->nprocs > 0 583 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 584 if (found) 585 error("%s: ambiguous", name); 586 found = jp; 587 } 588 } 589 if (found != NULL) 590 return (found); 591 } else { 592 found = NULL; 593 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 594 if (jp->used && jp->nprocs > 0 595 && prefix(name + 1, jp->ps[0].cmd)) { 596 if (found) 597 error("%s: ambiguous", name); 598 found = jp; 599 } 600 } 601 if (found) 602 return found; 603 } 604 } else if (is_number(name)) { 605 pid = (pid_t)number(name); 606 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 607 if (jp->used && jp->nprocs > 0 608 && jp->ps[jp->nprocs - 1].pid == pid) 609 return jp; 610 } 611 } 612 error("No such job: %s", name); 613 /*NOTREACHED*/ 614 return NULL; 615 } 616 617 618 pid_t 619 getjobpgrp(char *name) 620 { 621 struct job *jp; 622 623 jp = getjob(name); 624 return -jp->ps[0].pid; 625 } 626 627 /* 628 * Return a new job structure, 629 */ 630 631 struct job * 632 makejob(union node *node __unused, int nprocs) 633 { 634 int i; 635 struct job *jp; 636 637 for (i = njobs, jp = jobtab ; ; jp++) { 638 if (--i < 0) { 639 INTOFF; 640 if (njobs == 0) { 641 jobtab = ckmalloc(4 * sizeof jobtab[0]); 642 #if JOBS 643 jobmru = NULL; 644 #endif 645 } else { 646 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 647 memcpy(jp, jobtab, njobs * sizeof jp[0]); 648 #if JOBS 649 /* Relocate `next' pointers and list head */ 650 if (jobmru != NULL) 651 jobmru = &jp[jobmru - jobtab]; 652 for (i = 0; i < njobs; i++) 653 if (jp[i].next != NULL) 654 jp[i].next = &jp[jp[i].next - 655 jobtab]; 656 #endif 657 if (bgjob != NULL) 658 bgjob = &jp[bgjob - jobtab]; 659 /* Relocate `ps' pointers */ 660 for (i = 0; i < njobs; i++) 661 if (jp[i].ps == &jobtab[i].ps0) 662 jp[i].ps = &jp[i].ps0; 663 ckfree(jobtab); 664 jobtab = jp; 665 } 666 jp = jobtab + njobs; 667 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 668 INTON; 669 break; 670 } 671 if (jp->used == 0) 672 break; 673 } 674 INTOFF; 675 jp->state = 0; 676 jp->used = 1; 677 jp->changed = 0; 678 jp->nprocs = 0; 679 jp->foreground = 0; 680 jp->remembered = 0; 681 #if JOBS 682 jp->jobctl = jobctl; 683 jp->next = NULL; 684 #endif 685 if (nprocs > 1) { 686 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 687 } else { 688 jp->ps = &jp->ps0; 689 } 690 INTON; 691 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 692 jp - jobtab + 1)); 693 return jp; 694 } 695 696 #if JOBS 697 static void 698 setcurjob(struct job *cj) 699 { 700 struct job *jp, *prev; 701 702 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 703 if (jp == cj) { 704 if (prev != NULL) 705 prev->next = jp->next; 706 else 707 jobmru = jp->next; 708 jp->next = jobmru; 709 jobmru = cj; 710 return; 711 } 712 } 713 cj->next = jobmru; 714 jobmru = cj; 715 } 716 717 static void 718 deljob(struct job *j) 719 { 720 struct job *jp, *prev; 721 722 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 723 if (jp == j) { 724 if (prev != NULL) 725 prev->next = jp->next; 726 else 727 jobmru = jp->next; 728 return; 729 } 730 } 731 } 732 733 /* 734 * Return the most recently used job that isn't `nj', and preferably one 735 * that is stopped. 736 */ 737 static struct job * 738 getcurjob(struct job *nj) 739 { 740 struct job *jp; 741 742 /* Try to find a stopped one.. */ 743 for (jp = jobmru; jp != NULL; jp = jp->next) 744 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 745 return (jp); 746 /* Otherwise the most recently used job that isn't `nj' */ 747 for (jp = jobmru; jp != NULL; jp = jp->next) 748 if (jp->used && jp != nj) 749 return (jp); 750 751 return (NULL); 752 } 753 754 #endif 755 756 /* 757 * Fork of a subshell. If we are doing job control, give the subshell its 758 * own process group. Jp is a job structure that the job is to be added to. 759 * N is the command that will be evaluated by the child. Both jp and n may 760 * be NULL. The mode parameter can be one of the following: 761 * FORK_FG - Fork off a foreground process. 762 * FORK_BG - Fork off a background process. 763 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 764 * process group even if job control is on. 765 * 766 * When job control is turned off, background processes have their standard 767 * input redirected to /dev/null (except for the second and later processes 768 * in a pipeline). 769 */ 770 771 pid_t 772 forkshell(struct job *jp, union node *n, int mode) 773 { 774 pid_t pid; 775 pid_t pgrp; 776 777 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 778 mode)); 779 INTOFF; 780 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 781 checkzombies(); 782 flushall(); 783 pid = fork(); 784 if (pid == -1) { 785 TRACE(("Fork failed, errno=%d\n", errno)); 786 INTON; 787 error("Cannot fork: %s", strerror(errno)); 788 } 789 if (pid == 0) { 790 struct job *p; 791 int wasroot; 792 int i; 793 794 TRACE(("Child shell %d\n", (int)getpid())); 795 wasroot = rootshell; 796 rootshell = 0; 797 handler = &main_handler; 798 closescript(); 799 INTON; 800 clear_traps(); 801 #if JOBS 802 jobctl = 0; /* do job control only in root shell */ 803 if (wasroot && mode != FORK_NOJOB && mflag) { 804 if (jp == NULL || jp->nprocs == 0) 805 pgrp = getpid(); 806 else 807 pgrp = jp->ps[0].pid; 808 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 809 /*** this causes superfluous TIOCSPGRPS ***/ 810 if (tcsetpgrp(ttyfd, pgrp) < 0) 811 error("tcsetpgrp failed, errno=%d", errno); 812 } 813 setsignal(SIGTSTP); 814 setsignal(SIGTTOU); 815 } else if (mode == FORK_BG) { 816 ignoresig(SIGINT); 817 ignoresig(SIGQUIT); 818 if ((jp == NULL || jp->nprocs == 0) && 819 ! fd0_redirected_p ()) { 820 close(0); 821 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 822 error("Can't open %s: %s", 823 _PATH_DEVNULL, strerror(errno)); 824 } 825 } 826 #else 827 if (mode == FORK_BG) { 828 ignoresig(SIGINT); 829 ignoresig(SIGQUIT); 830 if ((jp == NULL || jp->nprocs == 0) && 831 ! fd0_redirected_p ()) { 832 close(0); 833 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 834 error("Can't open %s: %s", 835 _PATH_DEVNULL, strerror(errno)); 836 } 837 } 838 #endif 839 INTOFF; 840 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 841 if (p->used) 842 freejob(p); 843 INTON; 844 if (wasroot && iflag) { 845 setsignal(SIGINT); 846 setsignal(SIGQUIT); 847 setsignal(SIGTERM); 848 } 849 return pid; 850 } 851 if (rootshell && mode != FORK_NOJOB && mflag) { 852 if (jp == NULL || jp->nprocs == 0) 853 pgrp = pid; 854 else 855 pgrp = jp->ps[0].pid; 856 setpgid(pid, pgrp); 857 } 858 if (mode == FORK_BG) { 859 if (bgjob != NULL && bgjob->state == JOBDONE && 860 !bgjob->remembered && !iflag) 861 freejob(bgjob); 862 backgndpid = pid; /* set $! */ 863 bgjob = jp; 864 } 865 if (jp) { 866 struct procstat *ps = &jp->ps[jp->nprocs++]; 867 ps->pid = pid; 868 ps->status = -1; 869 ps->cmd = nullstr; 870 if (iflag && rootshell && n) 871 ps->cmd = commandtext(n); 872 jp->foreground = mode == FORK_FG; 873 #if JOBS 874 setcurjob(jp); 875 #endif 876 } 877 INTON; 878 TRACE(("In parent shell: child = %d\n", (int)pid)); 879 return pid; 880 } 881 882 883 884 /* 885 * Wait for job to finish. 886 * 887 * Under job control we have the problem that while a child process is 888 * running interrupts generated by the user are sent to the child but not 889 * to the shell. This means that an infinite loop started by an inter- 890 * active user may be hard to kill. With job control turned off, an 891 * interactive user may place an interactive program inside a loop. If 892 * the interactive program catches interrupts, the user doesn't want 893 * these interrupts to also abort the loop. The approach we take here 894 * is to have the shell ignore interrupt signals while waiting for a 895 * foreground process to terminate, and then send itself an interrupt 896 * signal if the child process was terminated by an interrupt signal. 897 * Unfortunately, some programs want to do a bit of cleanup and then 898 * exit on interrupt; unless these processes terminate themselves by 899 * sending a signal to themselves (instead of calling exit) they will 900 * confuse this approach. 901 */ 902 903 int 904 waitforjob(struct job *jp, int *origstatus) 905 { 906 #if JOBS 907 pid_t mypgrp = getpgrp(); 908 int propagate_int = jp->jobctl && jp->foreground; 909 #endif 910 int status; 911 int st; 912 913 INTOFF; 914 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 915 while (jp->state == 0) 916 if (dowait(1, jp) == -1) 917 dotrap(); 918 #if JOBS 919 if (jp->jobctl) { 920 if (tcsetpgrp(ttyfd, mypgrp) < 0) 921 error("tcsetpgrp failed, errno=%d\n", errno); 922 } 923 if (jp->state == JOBSTOPPED) 924 setcurjob(jp); 925 #endif 926 status = jp->ps[jp->nprocs - 1].status; 927 if (origstatus != NULL) 928 *origstatus = status; 929 /* convert to 8 bits */ 930 if (WIFEXITED(status)) 931 st = WEXITSTATUS(status); 932 #if JOBS 933 else if (WIFSTOPPED(status)) 934 st = WSTOPSIG(status) + 128; 935 #endif 936 else 937 st = WTERMSIG(status) + 128; 938 if (! JOBS || jp->state == JOBDONE) 939 freejob(jp); 940 if (int_pending()) { 941 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 942 CLEAR_PENDING_INT; 943 } 944 #if JOBS 945 else if (rootshell && iflag && propagate_int && 946 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 947 kill(getpid(), SIGINT); 948 #endif 949 INTON; 950 return st; 951 } 952 953 954 955 /* 956 * Wait for a process to terminate. 957 */ 958 959 static pid_t 960 dowait(int block, struct job *job) 961 { 962 pid_t pid; 963 int status; 964 struct procstat *sp; 965 struct job *jp; 966 struct job *thisjob; 967 int done; 968 int stopped; 969 int sig; 970 int coredump; 971 972 in_dowait++; 973 TRACE(("dowait(%d) called\n", block)); 974 do { 975 pid = waitproc(block, &status); 976 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 977 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 978 (pid > 0 && WIFSTOPPED(status) && !iflag)); 979 in_dowait--; 980 if (pid == -1 && errno == ECHILD && job != NULL) 981 job->state = JOBDONE; 982 if (breakwaitcmd != 0) { 983 breakwaitcmd = 0; 984 /* 985 * Do not early terminate if the pid is positive, else the 986 * job will not be properly recorded. 987 */ 988 if (pid <= 0) 989 return -1; 990 } 991 if (pid <= 0) 992 return pid; 993 INTOFF; 994 thisjob = NULL; 995 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 996 if (jp->used && jp->nprocs > 0) { 997 done = 1; 998 stopped = 1; 999 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1000 if (sp->pid == -1) 1001 continue; 1002 if (sp->pid == pid) { 1003 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1004 (int)pid, sp->status, 1005 status)); 1006 sp->status = status; 1007 thisjob = jp; 1008 } 1009 if (sp->status == -1) 1010 stopped = 0; 1011 else if (WIFSTOPPED(sp->status)) 1012 done = 0; 1013 } 1014 if (stopped) { /* stopped or done */ 1015 int state = done? JOBDONE : JOBSTOPPED; 1016 if (jp->state != state) { 1017 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1018 jp->state = state; 1019 if (jp != job) { 1020 if (done && !jp->remembered && 1021 !iflag && jp != bgjob) 1022 freejob(jp); 1023 #if JOBS 1024 else if (done) 1025 deljob(jp); 1026 #endif 1027 } 1028 } 1029 } 1030 } 1031 } 1032 INTON; 1033 if (!thisjob || thisjob->state == 0) 1034 ; 1035 else if ((!rootshell || !iflag || thisjob == job) && 1036 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1037 sig = 0; 1038 coredump = 0; 1039 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1040 if (WIFSIGNALED(sp->status)) { 1041 sig = WTERMSIG(sp->status); 1042 coredump = WCOREDUMP(sp->status); 1043 } 1044 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1045 if (sig < sys_nsig && sys_siglist[sig]) 1046 out2str(sys_siglist[sig]); 1047 else 1048 outfmt(out2, "Signal %d", sig); 1049 if (coredump) 1050 out2str(" (core dumped)"); 1051 out2c('\n'); 1052 flushout(out2); 1053 } 1054 } else { 1055 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1056 thisjob->changed = 1; 1057 } 1058 return pid; 1059 } 1060 1061 1062 1063 /* 1064 * Do a wait system call. If job control is compiled in, we accept 1065 * stopped processes. If block is zero, we return a value of zero 1066 * rather than blocking. 1067 */ 1068 static pid_t 1069 waitproc(int block, int *status) 1070 { 1071 int flags; 1072 1073 #if JOBS 1074 flags = WUNTRACED; 1075 #else 1076 flags = 0; 1077 #endif 1078 if (block == 0) 1079 flags |= WNOHANG; 1080 return wait3(status, flags, NULL); 1081 } 1082 1083 /* 1084 * return 1 if there are stopped jobs, otherwise 0 1085 */ 1086 int job_warning = 0; 1087 int 1088 stoppedjobs(void) 1089 { 1090 int jobno; 1091 struct job *jp; 1092 1093 if (job_warning) 1094 return (0); 1095 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1096 if (jp->used == 0) 1097 continue; 1098 if (jp->state == JOBSTOPPED) { 1099 out2fmt_flush("You have stopped jobs.\n"); 1100 job_warning = 2; 1101 return (1); 1102 } 1103 } 1104 1105 return (0); 1106 } 1107 1108 1109 static void 1110 checkzombies(void) 1111 { 1112 while (njobs > 0 && dowait(0, NULL) > 0) 1113 ; 1114 } 1115 1116 1117 int 1118 backgndpidset(void) 1119 { 1120 return backgndpid != -1; 1121 } 1122 1123 1124 pid_t 1125 backgndpidval(void) 1126 { 1127 if (bgjob != NULL) 1128 bgjob->remembered = 1; 1129 return backgndpid; 1130 } 1131 1132 /* 1133 * Return a string identifying a command (to be printed by the 1134 * jobs command. 1135 */ 1136 1137 static char *cmdnextc; 1138 static int cmdnleft; 1139 #define MAXCMDTEXT 200 1140 1141 char * 1142 commandtext(union node *n) 1143 { 1144 char *name; 1145 1146 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1147 cmdnleft = MAXCMDTEXT - 4; 1148 cmdtxt(n); 1149 *cmdnextc = '\0'; 1150 return name; 1151 } 1152 1153 1154 static void 1155 cmdtxt(union node *n) 1156 { 1157 union node *np; 1158 struct nodelist *lp; 1159 const char *p; 1160 int i; 1161 char s[2]; 1162 1163 if (n == NULL) 1164 return; 1165 switch (n->type) { 1166 case NSEMI: 1167 cmdtxt(n->nbinary.ch1); 1168 cmdputs("; "); 1169 cmdtxt(n->nbinary.ch2); 1170 break; 1171 case NAND: 1172 cmdtxt(n->nbinary.ch1); 1173 cmdputs(" && "); 1174 cmdtxt(n->nbinary.ch2); 1175 break; 1176 case NOR: 1177 cmdtxt(n->nbinary.ch1); 1178 cmdputs(" || "); 1179 cmdtxt(n->nbinary.ch2); 1180 break; 1181 case NPIPE: 1182 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1183 cmdtxt(lp->n); 1184 if (lp->next) 1185 cmdputs(" | "); 1186 } 1187 break; 1188 case NSUBSHELL: 1189 cmdputs("("); 1190 cmdtxt(n->nredir.n); 1191 cmdputs(")"); 1192 break; 1193 case NREDIR: 1194 case NBACKGND: 1195 cmdtxt(n->nredir.n); 1196 break; 1197 case NIF: 1198 cmdputs("if "); 1199 cmdtxt(n->nif.test); 1200 cmdputs("; then "); 1201 cmdtxt(n->nif.ifpart); 1202 cmdputs("..."); 1203 break; 1204 case NWHILE: 1205 cmdputs("while "); 1206 goto until; 1207 case NUNTIL: 1208 cmdputs("until "); 1209 until: 1210 cmdtxt(n->nbinary.ch1); 1211 cmdputs("; do "); 1212 cmdtxt(n->nbinary.ch2); 1213 cmdputs("; done"); 1214 break; 1215 case NFOR: 1216 cmdputs("for "); 1217 cmdputs(n->nfor.var); 1218 cmdputs(" in ..."); 1219 break; 1220 case NCASE: 1221 cmdputs("case "); 1222 cmdputs(n->ncase.expr->narg.text); 1223 cmdputs(" in ..."); 1224 break; 1225 case NDEFUN: 1226 cmdputs(n->narg.text); 1227 cmdputs("() ..."); 1228 break; 1229 case NCMD: 1230 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1231 cmdtxt(np); 1232 if (np->narg.next) 1233 cmdputs(" "); 1234 } 1235 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1236 cmdputs(" "); 1237 cmdtxt(np); 1238 } 1239 break; 1240 case NARG: 1241 cmdputs(n->narg.text); 1242 break; 1243 case NTO: 1244 p = ">"; i = 1; goto redir; 1245 case NAPPEND: 1246 p = ">>"; i = 1; goto redir; 1247 case NTOFD: 1248 p = ">&"; i = 1; goto redir; 1249 case NCLOBBER: 1250 p = ">|"; i = 1; goto redir; 1251 case NFROM: 1252 p = "<"; i = 0; goto redir; 1253 case NFROMTO: 1254 p = "<>"; i = 0; goto redir; 1255 case NFROMFD: 1256 p = "<&"; i = 0; goto redir; 1257 redir: 1258 if (n->nfile.fd != i) { 1259 s[0] = n->nfile.fd + '0'; 1260 s[1] = '\0'; 1261 cmdputs(s); 1262 } 1263 cmdputs(p); 1264 if (n->type == NTOFD || n->type == NFROMFD) { 1265 if (n->ndup.dupfd >= 0) 1266 s[0] = n->ndup.dupfd + '0'; 1267 else 1268 s[0] = '-'; 1269 s[1] = '\0'; 1270 cmdputs(s); 1271 } else { 1272 cmdtxt(n->nfile.fname); 1273 } 1274 break; 1275 case NHERE: 1276 case NXHERE: 1277 cmdputs("<<..."); 1278 break; 1279 default: 1280 cmdputs("???"); 1281 break; 1282 } 1283 } 1284 1285 1286 1287 static void 1288 cmdputs(const char *s) 1289 { 1290 const char *p; 1291 char *q; 1292 char c; 1293 int subtype = 0; 1294 1295 if (cmdnleft <= 0) 1296 return; 1297 p = s; 1298 q = cmdnextc; 1299 while ((c = *p++) != '\0') { 1300 if (c == CTLESC) 1301 *q++ = *p++; 1302 else if (c == CTLVAR) { 1303 *q++ = '$'; 1304 if (--cmdnleft > 0) 1305 *q++ = '{'; 1306 subtype = *p++; 1307 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1308 *q++ = '#'; 1309 } else if (c == '=' && subtype != 0) { 1310 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1311 if (*q) 1312 q++; 1313 else 1314 cmdnleft++; 1315 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1316 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1317 --cmdnleft > 0) 1318 *q = q[-1], q++; 1319 subtype = 0; 1320 } else if (c == CTLENDVAR) { 1321 *q++ = '}'; 1322 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1323 cmdnleft -= 5; 1324 if (cmdnleft > 0) { 1325 *q++ = '$'; 1326 *q++ = '('; 1327 *q++ = '.'; 1328 *q++ = '.'; 1329 *q++ = '.'; 1330 *q++ = ')'; 1331 } 1332 } else if (c == CTLARI) { 1333 cmdnleft -= 2; 1334 if (cmdnleft > 0) { 1335 *q++ = '$'; 1336 *q++ = '('; 1337 *q++ = '('; 1338 } 1339 p++; 1340 } else if (c == CTLENDARI) { 1341 if (--cmdnleft > 0) { 1342 *q++ = ')'; 1343 *q++ = ')'; 1344 } 1345 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1346 cmdnleft++; /* ignore */ 1347 else 1348 *q++ = c; 1349 if (--cmdnleft <= 0) { 1350 *q++ = '.'; 1351 *q++ = '.'; 1352 *q++ = '.'; 1353 break; 1354 } 1355 } 1356 cmdnextc = q; 1357 } 1358