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 1.97 2012/02/04 23:12:14 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 "exec.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 #include "var.h" 74 #include "builtins.h" 75 76 77 static struct job *jobtab; /* array of jobs */ 78 static int njobs; /* size of array */ 79 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 80 MKINIT struct job *bgjob = NULL; /* last background process */ 81 #if JOBS 82 static struct job *jobmru; /* most recently used job list */ 83 static pid_t initialpgrp; /* pgrp of shell on invocation */ 84 #endif 85 int in_waitcmd = 0; /* are we in waitcmd()? */ 86 int in_dowait = 0; /* are we in dowait()? */ 87 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 88 static int ttyfd = -1; 89 90 #if JOBS 91 static void restartjob(struct job *); 92 #endif 93 static void freejob(struct job *); 94 static struct job *getjob(char *); 95 static pid_t dowait(int, struct job *); 96 static pid_t waitproc(int, int *); 97 static void checkzombies(void); 98 static void cmdtxt(union node *); 99 static void cmdputs(const char *); 100 #if JOBS 101 static void setcurjob(struct job *); 102 static void deljob(struct job *); 103 static struct job *getcurjob(struct job *); 104 #endif 105 static void printjobcmd(struct job *); 106 static void showjob(struct job *, int); 107 108 109 /* 110 * Turn job control on and off. 111 */ 112 113 MKINIT int jobctl; 114 115 #if JOBS 116 void 117 setjobctl(int on) 118 { 119 int i; 120 121 if (on == jobctl || rootshell == 0) 122 return; 123 if (on) { 124 if (ttyfd != -1) 125 close(ttyfd); 126 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 127 i = 0; 128 while (i <= 2 && !isatty(i)) 129 i++; 130 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 131 goto out; 132 } 133 if (ttyfd < 10) { 134 /* 135 * Keep our TTY file descriptor out of the way of 136 * the user's redirections. 137 */ 138 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 139 close(ttyfd); 140 ttyfd = -1; 141 goto out; 142 } 143 close(ttyfd); 144 ttyfd = i; 145 } 146 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 147 close(ttyfd); 148 ttyfd = -1; 149 goto out; 150 } 151 do { /* while we are in the background */ 152 initialpgrp = tcgetpgrp(ttyfd); 153 if (initialpgrp < 0) { 154 out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 155 mflag = 0; 156 return; 157 } 158 if (initialpgrp != getpgrp()) { 159 kill(0, SIGTTIN); 160 continue; 161 } 162 } while (0); 163 setsignal(SIGTSTP); 164 setsignal(SIGTTOU); 165 setsignal(SIGTTIN); 166 setpgid(0, rootpid); 167 tcsetpgrp(ttyfd, rootpid); 168 } else { /* turning job control off */ 169 setpgid(0, initialpgrp); 170 tcsetpgrp(ttyfd, initialpgrp); 171 close(ttyfd); 172 ttyfd = -1; 173 setsignal(SIGTSTP); 174 setsignal(SIGTTOU); 175 setsignal(SIGTTIN); 176 } 177 jobctl = on; 178 } 179 #endif 180 181 182 #if JOBS 183 int 184 fgcmd(int argc __unused, char **argv) 185 { 186 struct job *jp; 187 pid_t pgrp; 188 int status; 189 190 jp = getjob(argv[1]); 191 if (jp->jobctl == 0) 192 error("job not created under job control"); 193 printjobcmd(jp); 194 flushout(&output); 195 pgrp = jp->ps[0].pid; 196 tcsetpgrp(ttyfd, pgrp); 197 restartjob(jp); 198 jp->foreground = 1; 199 INTOFF; 200 status = waitforjob(jp, NULL); 201 INTON; 202 return status; 203 } 204 205 206 int 207 bgcmd(int argc, char **argv) 208 { 209 struct job *jp; 210 211 do { 212 jp = getjob(*++argv); 213 if (jp->jobctl == 0) 214 error("job not created under job control"); 215 if (jp->state == JOBDONE) 216 continue; 217 restartjob(jp); 218 jp->foreground = 0; 219 out1fmt("[%td] ", jp - jobtab + 1); 220 printjobcmd(jp); 221 } while (--argc > 1); 222 return 0; 223 } 224 225 226 static void 227 restartjob(struct job *jp) 228 { 229 struct procstat *ps; 230 int i; 231 232 if (jp->state == JOBDONE) 233 return; 234 setcurjob(jp); 235 INTOFF; 236 kill(-jp->ps[0].pid, SIGCONT); 237 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 238 if (WIFSTOPPED(ps->status)) { 239 ps->status = -1; 240 jp->state = 0; 241 } 242 } 243 INTON; 244 } 245 #endif 246 247 248 int 249 jobscmd(int argc, char *argv[]) 250 { 251 char *id; 252 int ch, mode; 253 254 optind = optreset = 1; 255 opterr = 0; 256 mode = SHOWJOBS_DEFAULT; 257 while ((ch = getopt(argc, argv, "lps")) != -1) { 258 switch (ch) { 259 case 'l': 260 mode = SHOWJOBS_VERBOSE; 261 break; 262 case 'p': 263 mode = SHOWJOBS_PGIDS; 264 break; 265 case 's': 266 mode = SHOWJOBS_PIDS; 267 break; 268 case '?': 269 default: 270 error("unknown option: -%c", optopt); 271 } 272 } 273 argc -= optind; 274 argv += optind; 275 276 if (argc == 0) 277 showjobs(0, mode); 278 else 279 while ((id = *argv++) != NULL) 280 showjob(getjob(id), mode); 281 282 return (0); 283 } 284 285 static void 286 printjobcmd(struct job *jp) 287 { 288 struct procstat *ps; 289 int i; 290 291 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 292 out1str(ps->cmd); 293 if (i > 0) 294 out1str(" | "); 295 } 296 out1c('\n'); 297 } 298 299 static void 300 showjob(struct job *jp, int mode) 301 { 302 char s[64]; 303 char statestr[64]; 304 struct procstat *ps; 305 struct job *j; 306 int col, curr, i, jobno, prev, procno; 307 char c; 308 309 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 310 jobno = jp - jobtab + 1; 311 curr = prev = 0; 312 #if JOBS 313 if ((j = getcurjob(NULL)) != NULL) { 314 curr = j - jobtab + 1; 315 if ((j = getcurjob(j)) != NULL) 316 prev = j - jobtab + 1; 317 } 318 #endif 319 ps = jp->ps + jp->nprocs - 1; 320 if (jp->state == 0) { 321 strcpy(statestr, "Running"); 322 #if JOBS 323 } else if (jp->state == JOBSTOPPED) { 324 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 325 ps--; 326 if (WIFSTOPPED(ps->status)) 327 i = WSTOPSIG(ps->status); 328 else 329 i = -1; 330 if (i > 0 && i < sys_nsig && sys_siglist[i]) 331 strcpy(statestr, sys_siglist[i]); 332 else 333 strcpy(statestr, "Suspended"); 334 #endif 335 } else if (WIFEXITED(ps->status)) { 336 if (WEXITSTATUS(ps->status) == 0) 337 strcpy(statestr, "Done"); 338 else 339 fmtstr(statestr, 64, "Done(%d)", 340 WEXITSTATUS(ps->status)); 341 } else { 342 i = WTERMSIG(ps->status); 343 if (i > 0 && i < sys_nsig && sys_siglist[i]) 344 strcpy(statestr, sys_siglist[i]); 345 else 346 fmtstr(statestr, 64, "Signal %d", i); 347 if (WCOREDUMP(ps->status)) 348 strcat(statestr, " (core dumped)"); 349 } 350 351 for (ps = jp->ps ; ; ps++) { /* for each process */ 352 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 353 out1fmt("%d\n", (int)ps->pid); 354 goto skip; 355 } 356 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 357 goto skip; 358 if (jobno == curr && ps == jp->ps) 359 c = '+'; 360 else if (jobno == prev && ps == jp->ps) 361 c = '-'; 362 else 363 c = ' '; 364 if (ps == jp->ps) 365 fmtstr(s, 64, "[%d] %c ", jobno, c); 366 else 367 fmtstr(s, 64, " %c ", c); 368 out1str(s); 369 col = strlen(s); 370 if (mode == SHOWJOBS_VERBOSE) { 371 fmtstr(s, 64, "%d ", (int)ps->pid); 372 out1str(s); 373 col += strlen(s); 374 } 375 if (ps == jp->ps) { 376 out1str(statestr); 377 col += strlen(statestr); 378 } 379 do { 380 out1c(' '); 381 col++; 382 } while (col < 30); 383 if (mode == SHOWJOBS_VERBOSE) { 384 out1str(ps->cmd); 385 out1c('\n'); 386 } else 387 printjobcmd(jp); 388 skip: if (--procno <= 0) 389 break; 390 } 391 } 392 393 /* 394 * Print a list of jobs. If "change" is nonzero, only print jobs whose 395 * statuses have changed since the last call to showjobs. 396 * 397 * If the shell is interrupted in the process of creating a job, the 398 * result may be a job structure containing zero processes. Such structures 399 * will be freed here. 400 */ 401 402 void 403 showjobs(int change, int mode) 404 { 405 int jobno; 406 struct job *jp; 407 408 TRACE(("showjobs(%d) called\n", change)); 409 checkzombies(); 410 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 411 if (! jp->used) 412 continue; 413 if (jp->nprocs == 0) { 414 freejob(jp); 415 continue; 416 } 417 if (change && ! jp->changed) 418 continue; 419 showjob(jp, mode); 420 jp->changed = 0; 421 /* Hack: discard jobs for which $! has not been referenced 422 * in interactive mode when they terminate. 423 */ 424 if (jp->state == JOBDONE && !jp->remembered && 425 (iflag || jp != bgjob)) { 426 freejob(jp); 427 } 428 } 429 } 430 431 432 /* 433 * Mark a job structure as unused. 434 */ 435 436 static void 437 freejob(struct job *jp) 438 { 439 struct procstat *ps; 440 int i; 441 442 INTOFF; 443 if (bgjob == jp) 444 bgjob = NULL; 445 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 446 if (ps->cmd != nullstr) 447 ckfree(ps->cmd); 448 } 449 if (jp->ps != &jp->ps0) 450 ckfree(jp->ps); 451 jp->used = 0; 452 #if JOBS 453 deljob(jp); 454 #endif 455 INTON; 456 } 457 458 459 460 int 461 waitcmd(int argc, char **argv) 462 { 463 struct job *job; 464 int status, retval; 465 struct job *jp; 466 467 if (argc > 1) { 468 job = getjob(argv[1]); 469 } else { 470 job = NULL; 471 } 472 473 /* 474 * Loop until a process is terminated or stopped, or a SIGINT is 475 * received. 476 */ 477 478 in_waitcmd++; 479 do { 480 if (job != NULL) { 481 if (job->state) { 482 status = job->ps[job->nprocs - 1].status; 483 if (WIFEXITED(status)) 484 retval = WEXITSTATUS(status); 485 #if JOBS 486 else if (WIFSTOPPED(status)) 487 retval = WSTOPSIG(status) + 128; 488 #endif 489 else 490 retval = WTERMSIG(status) + 128; 491 if (! iflag || ! job->changed) 492 freejob(job); 493 else { 494 job->remembered = 0; 495 if (job == bgjob) 496 bgjob = NULL; 497 } 498 in_waitcmd--; 499 return retval; 500 } 501 } else { 502 for (jp = jobtab ; jp < jobtab + njobs; jp++) 503 if (jp->used && jp->state == JOBDONE) { 504 if (! iflag || ! jp->changed) 505 freejob(jp); 506 else { 507 jp->remembered = 0; 508 if (jp == bgjob) 509 bgjob = NULL; 510 } 511 } 512 for (jp = jobtab ; ; jp++) { 513 if (jp >= jobtab + njobs) { /* no running procs */ 514 in_waitcmd--; 515 return 0; 516 } 517 if (jp->used && jp->state == 0) 518 break; 519 } 520 } 521 } while (dowait(1, NULL) != -1); 522 in_waitcmd--; 523 524 return 0; 525 } 526 527 528 529 int 530 jobidcmd(int argc __unused, char **argv) 531 { 532 struct job *jp; 533 int i; 534 535 jp = getjob(argv[1]); 536 for (i = 0 ; i < jp->nprocs ; ) { 537 out1fmt("%d", (int)jp->ps[i].pid); 538 out1c(++i < jp->nprocs? ' ' : '\n'); 539 } 540 return 0; 541 } 542 543 544 545 /* 546 * Convert a job name to a job structure. 547 */ 548 549 static struct job * 550 getjob(char *name) 551 { 552 int jobno; 553 struct job *found, *jp; 554 pid_t pid; 555 int i; 556 557 if (name == NULL) { 558 #if JOBS 559 currentjob: if ((jp = getcurjob(NULL)) == NULL) 560 error("No current job"); 561 return (jp); 562 #else 563 error("No current job"); 564 #endif 565 } else if (name[0] == '%') { 566 if (is_digit(name[1])) { 567 jobno = number(name + 1); 568 if (jobno > 0 && jobno <= njobs 569 && jobtab[jobno - 1].used != 0) 570 return &jobtab[jobno - 1]; 571 #if JOBS 572 } else if (name[1] == '%' && name[2] == '\0') { 573 goto currentjob; 574 } else if (name[1] == '+' && name[2] == '\0') { 575 goto currentjob; 576 } else if (name[1] == '-' && name[2] == '\0') { 577 if ((jp = getcurjob(NULL)) == NULL || 578 (jp = getcurjob(jp)) == NULL) 579 error("No previous job"); 580 return (jp); 581 #endif 582 } else if (name[1] == '?') { 583 found = NULL; 584 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 585 if (jp->used && jp->nprocs > 0 586 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 587 if (found) 588 error("%s: ambiguous", name); 589 found = jp; 590 } 591 } 592 if (found != NULL) 593 return (found); 594 } else { 595 found = NULL; 596 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 597 if (jp->used && jp->nprocs > 0 598 && prefix(name + 1, jp->ps[0].cmd)) { 599 if (found) 600 error("%s: ambiguous", name); 601 found = jp; 602 } 603 } 604 if (found) 605 return found; 606 } 607 } else if (is_number(name)) { 608 pid = (pid_t)number(name); 609 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 610 if (jp->used && jp->nprocs > 0 611 && jp->ps[jp->nprocs - 1].pid == pid) 612 return jp; 613 } 614 } 615 error("No such job: %s", name); 616 /*NOTREACHED*/ 617 return NULL; 618 } 619 620 621 pid_t 622 getjobpgrp(char *name) 623 { 624 struct job *jp; 625 626 jp = getjob(name); 627 return -jp->ps[0].pid; 628 } 629 630 /* 631 * Return a new job structure, 632 */ 633 634 struct job * 635 makejob(union node *node __unused, int nprocs) 636 { 637 int i; 638 struct job *jp; 639 640 for (i = njobs, jp = jobtab ; ; jp++) { 641 if (--i < 0) { 642 INTOFF; 643 if (njobs == 0) { 644 jobtab = ckmalloc(4 * sizeof jobtab[0]); 645 #if JOBS 646 jobmru = NULL; 647 #endif 648 } else { 649 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 650 memcpy(jp, jobtab, njobs * sizeof jp[0]); 651 #if JOBS 652 /* Relocate `next' pointers and list head */ 653 if (jobmru != NULL) 654 jobmru = &jp[jobmru - jobtab]; 655 for (i = 0; i < njobs; i++) 656 if (jp[i].next != NULL) 657 jp[i].next = &jp[jp[i].next - 658 jobtab]; 659 #endif 660 if (bgjob != NULL) 661 bgjob = &jp[bgjob - jobtab]; 662 /* Relocate `ps' pointers */ 663 for (i = 0; i < njobs; i++) 664 if (jp[i].ps == &jobtab[i].ps0) 665 jp[i].ps = &jp[i].ps0; 666 ckfree(jobtab); 667 jobtab = jp; 668 } 669 jp = jobtab + njobs; 670 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 671 INTON; 672 break; 673 } 674 if (jp->used == 0) 675 break; 676 } 677 INTOFF; 678 jp->state = 0; 679 jp->used = 1; 680 jp->changed = 0; 681 jp->nprocs = 0; 682 jp->foreground = 0; 683 jp->remembered = 0; 684 #if JOBS 685 jp->jobctl = jobctl; 686 jp->next = NULL; 687 #endif 688 if (nprocs > 1) { 689 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 690 } else { 691 jp->ps = &jp->ps0; 692 } 693 INTON; 694 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 695 jp - jobtab + 1)); 696 return jp; 697 } 698 699 #if JOBS 700 static void 701 setcurjob(struct job *cj) 702 { 703 struct job *jp, *prev; 704 705 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 706 if (jp == cj) { 707 if (prev != NULL) 708 prev->next = jp->next; 709 else 710 jobmru = jp->next; 711 jp->next = jobmru; 712 jobmru = cj; 713 return; 714 } 715 } 716 cj->next = jobmru; 717 jobmru = cj; 718 } 719 720 static void 721 deljob(struct job *j) 722 { 723 struct job *jp, *prev; 724 725 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 726 if (jp == j) { 727 if (prev != NULL) 728 prev->next = jp->next; 729 else 730 jobmru = jp->next; 731 return; 732 } 733 } 734 } 735 736 /* 737 * Return the most recently used job that isn't `nj', and preferably one 738 * that is stopped. 739 */ 740 static struct job * 741 getcurjob(struct job *nj) 742 { 743 struct job *jp; 744 745 /* Try to find a stopped one.. */ 746 for (jp = jobmru; jp != NULL; jp = jp->next) 747 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 748 return (jp); 749 /* Otherwise the most recently used job that isn't `nj' */ 750 for (jp = jobmru; jp != NULL; jp = jp->next) 751 if (jp->used && jp != nj) 752 return (jp); 753 754 return (NULL); 755 } 756 757 #endif 758 759 /* 760 * Fork of a subshell. If we are doing job control, give the subshell its 761 * own process group. Jp is a job structure that the job is to be added to. 762 * N is the command that will be evaluated by the child. Both jp and n may 763 * be NULL. The mode parameter can be one of the following: 764 * FORK_FG - Fork off a foreground process. 765 * FORK_BG - Fork off a background process. 766 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 767 * process group even if job control is on. 768 * 769 * When job control is turned off, background processes have their standard 770 * input redirected to /dev/null (except for the second and later processes 771 * in a pipeline). 772 */ 773 774 pid_t 775 forkshell(struct job *jp, union node *n, int mode) 776 { 777 pid_t pid; 778 pid_t pgrp; 779 780 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 781 mode)); 782 INTOFF; 783 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 784 checkzombies(); 785 flushall(); 786 pid = fork(); 787 if (pid == -1) { 788 TRACE(("Fork failed, errno=%d\n", errno)); 789 INTON; 790 error("Cannot fork: %s", strerror(errno)); 791 } 792 if (pid == 0) { 793 struct job *p; 794 int wasroot; 795 int i; 796 797 TRACE(("Child shell %d\n", (int)getpid())); 798 wasroot = rootshell; 799 rootshell = 0; 800 handler = &main_handler; 801 closescript(); 802 INTON; 803 forcelocal = 0; 804 clear_traps(); 805 #if JOBS 806 jobctl = 0; /* do job control only in root shell */ 807 if (wasroot && mode != FORK_NOJOB && mflag) { 808 if (jp == NULL || jp->nprocs == 0) 809 pgrp = getpid(); 810 else 811 pgrp = jp->ps[0].pid; 812 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 813 /*** this causes superfluous TIOCSPGRPS ***/ 814 if (tcsetpgrp(ttyfd, pgrp) < 0) 815 error("tcsetpgrp failed, errno=%d", errno); 816 } 817 setsignal(SIGTSTP); 818 setsignal(SIGTTOU); 819 } else if (mode == FORK_BG) { 820 ignoresig(SIGINT); 821 ignoresig(SIGQUIT); 822 if ((jp == NULL || jp->nprocs == 0) && 823 ! fd0_redirected_p ()) { 824 close(0); 825 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 826 error("cannot open %s: %s", 827 _PATH_DEVNULL, strerror(errno)); 828 } 829 } 830 #else 831 if (mode == FORK_BG) { 832 ignoresig(SIGINT); 833 ignoresig(SIGQUIT); 834 if ((jp == NULL || jp->nprocs == 0) && 835 ! fd0_redirected_p ()) { 836 close(0); 837 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 838 error("cannot open %s: %s", 839 _PATH_DEVNULL, strerror(errno)); 840 } 841 } 842 #endif 843 INTOFF; 844 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 845 if (p->used) 846 freejob(p); 847 INTON; 848 if (wasroot && iflag) { 849 setsignal(SIGINT); 850 setsignal(SIGQUIT); 851 setsignal(SIGTERM); 852 } 853 return pid; 854 } 855 if (rootshell && mode != FORK_NOJOB && mflag) { 856 if (jp == NULL || jp->nprocs == 0) 857 pgrp = pid; 858 else 859 pgrp = jp->ps[0].pid; 860 setpgid(pid, pgrp); 861 } 862 if (mode == FORK_BG) { 863 if (bgjob != NULL && bgjob->state == JOBDONE && 864 !bgjob->remembered && !iflag) 865 freejob(bgjob); 866 backgndpid = pid; /* set $! */ 867 bgjob = jp; 868 } 869 if (jp) { 870 struct procstat *ps = &jp->ps[jp->nprocs++]; 871 ps->pid = pid; 872 ps->status = -1; 873 ps->cmd = nullstr; 874 if (iflag && rootshell && n) 875 ps->cmd = commandtext(n); 876 jp->foreground = mode == FORK_FG; 877 #if JOBS 878 setcurjob(jp); 879 #endif 880 } 881 INTON; 882 TRACE(("In parent shell: child = %d\n", (int)pid)); 883 return pid; 884 } 885 886 887 pid_t 888 vforkexecshell(struct job *jp, char **argv, char **envp, const char *path, int idx, int pip[2]) 889 { 890 pid_t pid; 891 struct jmploc jmploc; 892 struct jmploc *savehandler; 893 894 TRACE(("vforkexecshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 895 mode)); 896 INTOFF; 897 flushall(); 898 savehandler = handler; 899 pid = vfork(); 900 if (pid == -1) { 901 TRACE(("Vfork failed, errno=%d\n", errno)); 902 INTON; 903 error("Cannot fork: %s", strerror(errno)); 904 } 905 if (pid == 0) { 906 TRACE(("Child shell %d\n", (int)getpid())); 907 if (setjmp(jmploc.loc)) 908 _exit(exception == EXEXEC ? exerrno : 2); 909 if (pip != NULL) { 910 close(pip[0]); 911 if (pip[1] != 1) { 912 dup2(pip[1], 1); 913 close(pip[1]); 914 } 915 } 916 handler = &jmploc; 917 shellexec(argv, envp, path, idx); 918 } 919 handler = savehandler; 920 if (jp) { 921 struct procstat *ps = &jp->ps[jp->nprocs++]; 922 ps->pid = pid; 923 ps->status = -1; 924 ps->cmd = nullstr; 925 jp->foreground = 1; 926 #if JOBS 927 setcurjob(jp); 928 #endif 929 } 930 INTON; 931 TRACE(("In parent shell: child = %d\n", (int)pid)); 932 return pid; 933 } 934 935 936 /* 937 * Wait for job to finish. 938 * 939 * Under job control we have the problem that while a child process is 940 * running interrupts generated by the user are sent to the child but not 941 * to the shell. This means that an infinite loop started by an inter- 942 * active user may be hard to kill. With job control turned off, an 943 * interactive user may place an interactive program inside a loop. If 944 * the interactive program catches interrupts, the user doesn't want 945 * these interrupts to also abort the loop. The approach we take here 946 * is to have the shell ignore interrupt signals while waiting for a 947 * foreground process to terminate, and then send itself an interrupt 948 * signal if the child process was terminated by an interrupt signal. 949 * Unfortunately, some programs want to do a bit of cleanup and then 950 * exit on interrupt; unless these processes terminate themselves by 951 * sending a signal to themselves (instead of calling exit) they will 952 * confuse this approach. 953 */ 954 955 int 956 waitforjob(struct job *jp, int *origstatus) 957 { 958 #if JOBS 959 pid_t mypgrp = getpgrp(); 960 int propagate_int = jp->jobctl && jp->foreground; 961 #endif 962 int status; 963 int st; 964 965 INTOFF; 966 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 967 while (jp->state == 0) 968 if (dowait(1, jp) == -1) 969 dotrap(); 970 #if JOBS 971 if (jp->jobctl) { 972 if (tcsetpgrp(ttyfd, mypgrp) < 0) 973 error("tcsetpgrp failed, errno=%d\n", errno); 974 } 975 if (jp->state == JOBSTOPPED) 976 setcurjob(jp); 977 #endif 978 status = jp->ps[jp->nprocs - 1].status; 979 if (origstatus != NULL) 980 *origstatus = status; 981 /* convert to 8 bits */ 982 if (WIFEXITED(status)) 983 st = WEXITSTATUS(status); 984 #if JOBS 985 else if (WIFSTOPPED(status)) 986 st = WSTOPSIG(status) + 128; 987 #endif 988 else 989 st = WTERMSIG(status) + 128; 990 if (! JOBS || jp->state == JOBDONE) 991 freejob(jp); 992 if (int_pending()) { 993 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 994 CLEAR_PENDING_INT; 995 } 996 #if JOBS 997 else if (rootshell && iflag && propagate_int && 998 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 999 kill(getpid(), SIGINT); 1000 #endif 1001 INTON; 1002 return st; 1003 } 1004 1005 1006 1007 /* 1008 * Wait for a process to terminate. 1009 */ 1010 1011 static pid_t 1012 dowait(int block, struct job *job) 1013 { 1014 pid_t pid; 1015 int status; 1016 struct procstat *sp; 1017 struct job *jp; 1018 struct job *thisjob; 1019 int done; 1020 int stopped; 1021 int sig; 1022 int coredump; 1023 1024 in_dowait++; 1025 TRACE(("dowait(%d) called\n", block)); 1026 do { 1027 pid = waitproc(block, &status); 1028 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 1029 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 1030 (pid > 0 && WIFSTOPPED(status) && !iflag)); 1031 in_dowait--; 1032 if (pid == -1 && errno == ECHILD && job != NULL) 1033 job->state = JOBDONE; 1034 if (breakwaitcmd != 0) { 1035 breakwaitcmd = 0; 1036 /* 1037 * Do not early terminate if the pid is positive, else the 1038 * job will not be properly recorded. 1039 */ 1040 if (pid <= 0) 1041 return -1; 1042 } 1043 if (pid <= 0) 1044 return pid; 1045 INTOFF; 1046 thisjob = NULL; 1047 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1048 if (jp->used && jp->nprocs > 0) { 1049 done = 1; 1050 stopped = 1; 1051 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1052 if (sp->pid == -1) 1053 continue; 1054 if (sp->pid == pid) { 1055 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1056 (int)pid, sp->status, 1057 status)); 1058 sp->status = status; 1059 thisjob = jp; 1060 } 1061 if (sp->status == -1) 1062 stopped = 0; 1063 else if (WIFSTOPPED(sp->status)) 1064 done = 0; 1065 } 1066 if (stopped) { /* stopped or done */ 1067 int state = done? JOBDONE : JOBSTOPPED; 1068 if (jp->state != state) { 1069 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1070 jp->state = state; 1071 if (jp != job) { 1072 if (done && !jp->remembered && 1073 !iflag && jp != bgjob) 1074 freejob(jp); 1075 #if JOBS 1076 else if (done) 1077 deljob(jp); 1078 #endif 1079 } 1080 } 1081 } 1082 } 1083 } 1084 INTON; 1085 if (!thisjob || thisjob->state == 0) 1086 ; 1087 else if ((!rootshell || !iflag || thisjob == job) && 1088 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1089 sig = 0; 1090 coredump = 0; 1091 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1092 if (WIFSIGNALED(sp->status)) { 1093 sig = WTERMSIG(sp->status); 1094 coredump = WCOREDUMP(sp->status); 1095 } 1096 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1097 if (sig < sys_nsig && sys_siglist[sig]) 1098 out2str(sys_siglist[sig]); 1099 else 1100 outfmt(out2, "Signal %d", sig); 1101 if (coredump) 1102 out2str(" (core dumped)"); 1103 out2c('\n'); 1104 flushout(out2); 1105 } 1106 } else { 1107 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1108 thisjob->changed = 1; 1109 } 1110 return pid; 1111 } 1112 1113 1114 1115 /* 1116 * Do a wait system call. If job control is compiled in, we accept 1117 * stopped processes. If block is zero, we return a value of zero 1118 * rather than blocking. 1119 */ 1120 static pid_t 1121 waitproc(int block, int *status) 1122 { 1123 int flags; 1124 1125 #if JOBS 1126 flags = WUNTRACED; 1127 #else 1128 flags = 0; 1129 #endif 1130 if (block == 0) 1131 flags |= WNOHANG; 1132 return wait3(status, flags, NULL); 1133 } 1134 1135 /* 1136 * return 1 if there are stopped jobs, otherwise 0 1137 */ 1138 int job_warning = 0; 1139 int 1140 stoppedjobs(void) 1141 { 1142 int jobno; 1143 struct job *jp; 1144 1145 if (job_warning) 1146 return (0); 1147 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1148 if (jp->used == 0) 1149 continue; 1150 if (jp->state == JOBSTOPPED) { 1151 out2fmt_flush("You have stopped jobs.\n"); 1152 job_warning = 2; 1153 return (1); 1154 } 1155 } 1156 1157 return (0); 1158 } 1159 1160 1161 static void 1162 checkzombies(void) 1163 { 1164 while (njobs > 0 && dowait(0, NULL) > 0) 1165 ; 1166 } 1167 1168 1169 int 1170 backgndpidset(void) 1171 { 1172 return backgndpid != -1; 1173 } 1174 1175 1176 pid_t 1177 backgndpidval(void) 1178 { 1179 if (bgjob != NULL && !forcelocal) 1180 bgjob->remembered = 1; 1181 return backgndpid; 1182 } 1183 1184 /* 1185 * Return a string identifying a command (to be printed by the 1186 * jobs command. 1187 */ 1188 1189 static char *cmdnextc; 1190 static int cmdnleft; 1191 #define MAXCMDTEXT 200 1192 1193 char * 1194 commandtext(union node *n) 1195 { 1196 char *name; 1197 1198 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1199 cmdnleft = MAXCMDTEXT - 4; 1200 cmdtxt(n); 1201 *cmdnextc = '\0'; 1202 return name; 1203 } 1204 1205 1206 static void 1207 cmdtxt(union node *n) 1208 { 1209 union node *np; 1210 struct nodelist *lp; 1211 const char *p; 1212 int i; 1213 char s[2]; 1214 1215 if (n == NULL) 1216 return; 1217 switch (n->type) { 1218 case NSEMI: 1219 cmdtxt(n->nbinary.ch1); 1220 cmdputs("; "); 1221 cmdtxt(n->nbinary.ch2); 1222 break; 1223 case NAND: 1224 cmdtxt(n->nbinary.ch1); 1225 cmdputs(" && "); 1226 cmdtxt(n->nbinary.ch2); 1227 break; 1228 case NOR: 1229 cmdtxt(n->nbinary.ch1); 1230 cmdputs(" || "); 1231 cmdtxt(n->nbinary.ch2); 1232 break; 1233 case NPIPE: 1234 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1235 cmdtxt(lp->n); 1236 if (lp->next) 1237 cmdputs(" | "); 1238 } 1239 break; 1240 case NSUBSHELL: 1241 cmdputs("("); 1242 cmdtxt(n->nredir.n); 1243 cmdputs(")"); 1244 break; 1245 case NREDIR: 1246 case NBACKGND: 1247 cmdtxt(n->nredir.n); 1248 break; 1249 case NIF: 1250 cmdputs("if "); 1251 cmdtxt(n->nif.test); 1252 cmdputs("; then "); 1253 cmdtxt(n->nif.ifpart); 1254 cmdputs("..."); 1255 break; 1256 case NWHILE: 1257 cmdputs("while "); 1258 goto until; 1259 case NUNTIL: 1260 cmdputs("until "); 1261 until: 1262 cmdtxt(n->nbinary.ch1); 1263 cmdputs("; do "); 1264 cmdtxt(n->nbinary.ch2); 1265 cmdputs("; done"); 1266 break; 1267 case NFOR: 1268 cmdputs("for "); 1269 cmdputs(n->nfor.var); 1270 cmdputs(" in ..."); 1271 break; 1272 case NCASE: 1273 cmdputs("case "); 1274 cmdputs(n->ncase.expr->narg.text); 1275 cmdputs(" in ..."); 1276 break; 1277 case NDEFUN: 1278 cmdputs(n->narg.text); 1279 cmdputs("() ..."); 1280 break; 1281 case NCMD: 1282 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1283 cmdtxt(np); 1284 if (np->narg.next) 1285 cmdputs(" "); 1286 } 1287 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1288 cmdputs(" "); 1289 cmdtxt(np); 1290 } 1291 break; 1292 case NARG: 1293 cmdputs(n->narg.text); 1294 break; 1295 case NTO: 1296 p = ">"; i = 1; goto redir; 1297 case NAPPEND: 1298 p = ">>"; i = 1; goto redir; 1299 case NTOFD: 1300 p = ">&"; i = 1; goto redir; 1301 case NCLOBBER: 1302 p = ">|"; i = 1; goto redir; 1303 case NFROM: 1304 p = "<"; i = 0; goto redir; 1305 case NFROMTO: 1306 p = "<>"; i = 0; goto redir; 1307 case NFROMFD: 1308 p = "<&"; i = 0; goto redir; 1309 redir: 1310 if (n->nfile.fd != i) { 1311 s[0] = n->nfile.fd + '0'; 1312 s[1] = '\0'; 1313 cmdputs(s); 1314 } 1315 cmdputs(p); 1316 if (n->type == NTOFD || n->type == NFROMFD) { 1317 if (n->ndup.dupfd >= 0) 1318 s[0] = n->ndup.dupfd + '0'; 1319 else 1320 s[0] = '-'; 1321 s[1] = '\0'; 1322 cmdputs(s); 1323 } else { 1324 cmdtxt(n->nfile.fname); 1325 } 1326 break; 1327 case NHERE: 1328 case NXHERE: 1329 cmdputs("<<..."); 1330 break; 1331 default: 1332 cmdputs("???"); 1333 break; 1334 } 1335 } 1336 1337 1338 1339 static void 1340 cmdputs(const char *s) 1341 { 1342 const char *p; 1343 char *q; 1344 char c; 1345 int subtype = 0; 1346 1347 if (cmdnleft <= 0) 1348 return; 1349 p = s; 1350 q = cmdnextc; 1351 while ((c = *p++) != '\0') { 1352 if (c == CTLESC) 1353 *q++ = *p++; 1354 else if (c == CTLVAR) { 1355 *q++ = '$'; 1356 if (--cmdnleft > 0) 1357 *q++ = '{'; 1358 subtype = *p++; 1359 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1360 *q++ = '#'; 1361 } else if (c == '=' && subtype != 0) { 1362 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1363 if (*q) 1364 q++; 1365 else 1366 cmdnleft++; 1367 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1368 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1369 --cmdnleft > 0) 1370 *q = q[-1], q++; 1371 subtype = 0; 1372 } else if (c == CTLENDVAR) { 1373 *q++ = '}'; 1374 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1375 cmdnleft -= 5; 1376 if (cmdnleft > 0) { 1377 *q++ = '$'; 1378 *q++ = '('; 1379 *q++ = '.'; 1380 *q++ = '.'; 1381 *q++ = '.'; 1382 *q++ = ')'; 1383 } 1384 } else if (c == CTLARI) { 1385 cmdnleft -= 2; 1386 if (cmdnleft > 0) { 1387 *q++ = '$'; 1388 *q++ = '('; 1389 *q++ = '('; 1390 } 1391 p++; 1392 } else if (c == CTLENDARI) { 1393 if (--cmdnleft > 0) { 1394 *q++ = ')'; 1395 *q++ = ')'; 1396 } 1397 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1398 cmdnleft++; /* ignore */ 1399 else 1400 *q++ = c; 1401 if (--cmdnleft <= 0) { 1402 *q++ = '.'; 1403 *q++ = '.'; 1404 *q++ = '.'; 1405 break; 1406 } 1407 } 1408 cmdnextc = q; 1409 } 1410