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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33#ifndef lint 34#if 0 35static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 36#endif 37#endif /* not lint */ 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD$"); 40 41#include <sys/ioctl.h> 42#include <sys/param.h> 43#include <sys/resource.h> 44#include <sys/time.h> 45#include <sys/wait.h> 46#include <errno.h> 47#include <fcntl.h> 48#include <paths.h> 49#include <signal.h> 50#include <stddef.h> 51#include <stdlib.h> 52#include <unistd.h> 53 54#include "shell.h" 55#if JOBS 56#include <termios.h> 57#undef CEOF /* syntax.h redefines this */ 58#endif 59#include "redir.h" 60#include "exec.h" 61#include "show.h" 62#include "main.h" 63#include "parser.h" 64#include "nodes.h" 65#include "jobs.h" 66#include "options.h" 67#include "trap.h" 68#include "syntax.h" 69#include "input.h" 70#include "output.h" 71#include "memalloc.h" 72#include "error.h" 73#include "mystring.h" 74#include "var.h" 75#include "builtins.h" 76 77 78static struct job *jobtab; /* array of jobs */ 79static int njobs; /* size of array */ 80MKINIT pid_t backgndpid = -1; /* pid of last background process */ 81MKINIT struct job *bgjob = NULL; /* last background process */ 82#if JOBS 83static struct job *jobmru; /* most recently used job list */ 84static pid_t initialpgrp; /* pgrp of shell on invocation */ 85#endif 86int in_waitcmd = 0; /* are we in waitcmd()? */ 87int in_dowait = 0; /* are we in dowait()? */ 88volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 89static int ttyfd = -1; 90 91#if JOBS 92static void restartjob(struct job *); 93#endif 94static void freejob(struct job *); 95static struct job *getjob(char *); 96static pid_t dowait(int, struct job *); 97static pid_t waitproc(int, int *); 98static void checkzombies(void); 99static void cmdtxt(union node *); 100static void cmdputs(const char *); 101#if JOBS 102static void setcurjob(struct job *); 103static void deljob(struct job *); 104static struct job *getcurjob(struct job *); 105#endif 106static void printjobcmd(struct job *); 107static void showjob(struct job *, int); 108 109 110/* 111 * Turn job control on and off. 112 */ 113 114MKINIT int jobctl; 115 116#if JOBS 117void 118setjobctl(int on) 119{ 120 int i; 121 122 if (on == jobctl || rootshell == 0) 123 return; 124 if (on) { 125 if (ttyfd != -1) 126 close(ttyfd); 127 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) { 128 i = 0; 129 while (i <= 2 && !isatty(i)) 130 i++; 131 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0) 132 goto out; 133 } 134 if (ttyfd < 10) { 135 /* 136 * Keep our TTY file descriptor out of the way of 137 * the user's redirections. 138 */ 139 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) { 140 close(ttyfd); 141 ttyfd = -1; 142 goto out; 143 } 144 close(ttyfd); 145 ttyfd = i; 146 } 147 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 148 close(ttyfd); 149 ttyfd = -1; 150 goto out; 151 } 152 do { /* while we are in the background */ 153 initialpgrp = tcgetpgrp(ttyfd); 154 if (initialpgrp < 0) { 155out: out2fmt_flush("sh: can't access tty; job control turned off\n"); 156 mflag = 0; 157 return; 158 } 159 if (initialpgrp != getpgrp()) { 160 kill(0, SIGTTIN); 161 continue; 162 } 163 } while (0); 164 setsignal(SIGTSTP); 165 setsignal(SIGTTOU); 166 setsignal(SIGTTIN); 167 setpgid(0, rootpid); 168 tcsetpgrp(ttyfd, rootpid); 169 } else { /* turning job control off */ 170 setpgid(0, initialpgrp); 171 tcsetpgrp(ttyfd, initialpgrp); 172 close(ttyfd); 173 ttyfd = -1; 174 setsignal(SIGTSTP); 175 setsignal(SIGTTOU); 176 setsignal(SIGTTIN); 177 } 178 jobctl = on; 179} 180#endif 181 182 183#if JOBS 184int 185fgcmd(int argc __unused, char **argv) 186{ 187 struct job *jp; 188 pid_t pgrp; 189 int status; 190 191 jp = getjob(argv[1]); 192 if (jp->jobctl == 0) 193 error("job not created under job control"); 194 printjobcmd(jp); 195 flushout(&output); 196 pgrp = jp->ps[0].pid; 197 tcsetpgrp(ttyfd, pgrp); 198 restartjob(jp); 199 jp->foreground = 1; 200 INTOFF; 201 status = waitforjob(jp, (int *)NULL); 202 INTON; 203 return status; 204} 205 206 207int 208bgcmd(int argc, char **argv) 209{ 210 struct job *jp; 211 212 do { 213 jp = getjob(*++argv); 214 if (jp->jobctl == 0) 215 error("job not created under job control"); 216 if (jp->state == JOBDONE) 217 continue; 218 restartjob(jp); 219 jp->foreground = 0; 220 out1fmt("[%td] ", jp - jobtab + 1); 221 printjobcmd(jp); 222 } while (--argc > 1); 223 return 0; 224} 225 226 227static void 228restartjob(struct job *jp) 229{ 230 struct procstat *ps; 231 int i; 232 233 if (jp->state == JOBDONE) 234 return; 235 setcurjob(jp); 236 INTOFF; 237 kill(-jp->ps[0].pid, SIGCONT); 238 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 239 if (WIFSTOPPED(ps->status)) { 240 ps->status = -1; 241 jp->state = 0; 242 } 243 } 244 INTON; 245} 246#endif 247 248 249int 250jobscmd(int argc, char *argv[]) 251{ 252 char *id; 253 int ch, mode; 254 255 optind = optreset = 1; 256 opterr = 0; 257 mode = SHOWJOBS_DEFAULT; 258 while ((ch = getopt(argc, argv, "lps")) != -1) { 259 switch (ch) { 260 case 'l': 261 mode = SHOWJOBS_VERBOSE; 262 break; 263 case 'p': 264 mode = SHOWJOBS_PGIDS; 265 break; 266 case 's': 267 mode = SHOWJOBS_PIDS; 268 break; 269 case '?': 270 default: 271 error("unknown option: -%c", optopt); 272 } 273 } 274 argc -= optind; 275 argv += optind; 276 277 if (argc == 0) 278 showjobs(0, mode); 279 else 280 while ((id = *argv++) != NULL) 281 showjob(getjob(id), mode); 282 283 return (0); 284} 285 286static void 287printjobcmd(struct job *jp) 288{ 289 struct procstat *ps; 290 int i; 291 292 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 293 out1str(ps->cmd); 294 if (i > 0) 295 out1str(" | "); 296 } 297 out1c('\n'); 298} 299 300static void 301showjob(struct job *jp, int mode) 302{ 303 char s[64]; 304 char statestr[64]; 305 struct procstat *ps; 306 struct job *j; 307 int col, curr, i, jobno, prev, procno; 308 char c; 309 310 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 311 jobno = jp - jobtab + 1; 312 curr = prev = 0; 313#if JOBS 314 if ((j = getcurjob(NULL)) != NULL) { 315 curr = j - jobtab + 1; 316 if ((j = getcurjob(j)) != NULL) 317 prev = j - jobtab + 1; 318 } 319#endif 320 ps = jp->ps + jp->nprocs - 1; 321 if (jp->state == 0) { 322 strcpy(statestr, "Running"); 323#if JOBS 324 } else if (jp->state == JOBSTOPPED) { 325 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 326 ps--; 327 if (WIFSTOPPED(ps->status)) 328 i = WSTOPSIG(ps->status); 329 else 330 i = -1; 331 if (i > 0 && i < sys_nsig && sys_siglist[i]) 332 strcpy(statestr, sys_siglist[i]); 333 else 334 strcpy(statestr, "Suspended"); 335#endif 336 } else if (WIFEXITED(ps->status)) { 337 if (WEXITSTATUS(ps->status) == 0) 338 strcpy(statestr, "Done"); 339 else 340 fmtstr(statestr, 64, "Done(%d)", 341 WEXITSTATUS(ps->status)); 342 } else { 343 i = WTERMSIG(ps->status); 344 if (i > 0 && i < sys_nsig && sys_siglist[i]) 345 strcpy(statestr, sys_siglist[i]); 346 else 347 fmtstr(statestr, 64, "Signal %d", i); 348 if (WCOREDUMP(ps->status)) 349 strcat(statestr, " (core dumped)"); 350 } 351 352 for (ps = jp->ps ; ; ps++) { /* for each process */ 353 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 354 out1fmt("%d\n", (int)ps->pid); 355 goto skip; 356 } 357 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 358 goto skip; 359 if (jobno == curr && ps == jp->ps) 360 c = '+'; 361 else if (jobno == prev && ps == jp->ps) 362 c = '-'; 363 else 364 c = ' '; 365 if (ps == jp->ps) 366 fmtstr(s, 64, "[%d] %c ", jobno, c); 367 else 368 fmtstr(s, 64, " %c ", c); 369 out1str(s); 370 col = strlen(s); 371 if (mode == SHOWJOBS_VERBOSE) { 372 fmtstr(s, 64, "%d ", (int)ps->pid); 373 out1str(s); 374 col += strlen(s); 375 } 376 if (ps == jp->ps) { 377 out1str(statestr); 378 col += strlen(statestr); 379 } 380 do { 381 out1c(' '); 382 col++; 383 } while (col < 30); 384 if (mode == SHOWJOBS_VERBOSE) { 385 out1str(ps->cmd); 386 out1c('\n'); 387 } else 388 printjobcmd(jp); 389skip: if (--procno <= 0) 390 break; 391 } 392} 393 394/* 395 * Print a list of jobs. If "change" is nonzero, only print jobs whose 396 * statuses have changed since the last call to showjobs. 397 * 398 * If the shell is interrupted in the process of creating a job, the 399 * result may be a job structure containing zero processes. Such structures 400 * will be freed here. 401 */ 402 403void 404showjobs(int change, int mode) 405{ 406 int jobno; 407 struct job *jp; 408 409 TRACE(("showjobs(%d) called\n", change)); 410 checkzombies(); 411 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 412 if (! jp->used) 413 continue; 414 if (jp->nprocs == 0) { 415 freejob(jp); 416 continue; 417 } 418 if (change && ! jp->changed) 419 continue; 420 showjob(jp, mode); 421 jp->changed = 0; 422 /* Hack: discard jobs for which $! has not been referenced 423 * in interactive mode when they terminate. 424 */ 425 if (jp->state == JOBDONE && !jp->remembered && 426 (iflag || jp != bgjob)) { 427 freejob(jp); 428 } 429 } 430} 431 432 433/* 434 * Mark a job structure as unused. 435 */ 436 437static void 438freejob(struct job *jp) 439{ 440 struct procstat *ps; 441 int i; 442 443 INTOFF; 444 if (bgjob == jp) 445 bgjob = NULL; 446 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 447 if (ps->cmd != nullstr) 448 ckfree(ps->cmd); 449 } 450 if (jp->ps != &jp->ps0) 451 ckfree(jp->ps); 452 jp->used = 0; 453#if JOBS 454 deljob(jp); 455#endif 456 INTON; 457} 458 459 460 461int 462waitcmd(int argc __unused, char **argv __unused) 463{ 464 struct job *job; 465 int status, retval; 466 struct job *jp; 467 468 nextopt(""); 469 if (*argptr != NULL) { 470 job = getjob(*argptr); 471 } else { 472 job = NULL; 473 } 474 475 /* 476 * Loop until a process is terminated or stopped, or a SIGINT is 477 * received. 478 */ 479 480 in_waitcmd++; 481 do { 482 if (job != NULL) { 483 if (job->state) { 484 status = job->ps[job->nprocs - 1].status; 485 if (WIFEXITED(status)) 486 retval = WEXITSTATUS(status); 487#if JOBS 488 else if (WIFSTOPPED(status)) 489 retval = WSTOPSIG(status) + 128; 490#endif 491 else 492 retval = WTERMSIG(status) + 128; 493 if (! iflag || ! job->changed) 494 freejob(job); 495 else { 496 job->remembered = 0; 497 if (job == bgjob) 498 bgjob = NULL; 499 } 500 in_waitcmd--; 501 return retval; 502 } 503 } else { 504 for (jp = jobtab ; jp < jobtab + njobs; jp++) 505 if (jp->used && jp->state == JOBDONE) { 506 if (! iflag || ! jp->changed) 507 freejob(jp); 508 else { 509 jp->remembered = 0; 510 if (jp == bgjob) 511 bgjob = NULL; 512 } 513 } 514 for (jp = jobtab ; ; jp++) { 515 if (jp >= jobtab + njobs) { /* no running procs */ 516 in_waitcmd--; 517 return 0; 518 } 519 if (jp->used && jp->state == 0) 520 break; 521 } 522 } 523 } while (dowait(1, (struct job *)NULL) != -1); 524 in_waitcmd--; 525 526 return 0; 527} 528 529 530 531int 532jobidcmd(int argc __unused, char **argv) 533{ 534 struct job *jp; 535 int i; 536 537 jp = getjob(argv[1]); 538 for (i = 0 ; i < jp->nprocs ; ) { 539 out1fmt("%d", (int)jp->ps[i].pid); 540 out1c(++i < jp->nprocs? ' ' : '\n'); 541 } 542 return 0; 543} 544 545 546 547/* 548 * Convert a job name to a job structure. 549 */ 550 551static struct job * 552getjob(char *name) 553{ 554 int jobno; 555 struct job *found, *jp; 556 pid_t pid; 557 int i; 558 559 if (name == NULL) { 560#if JOBS 561currentjob: if ((jp = getcurjob(NULL)) == NULL) 562 error("No current job"); 563 return (jp); 564#else 565 error("No current job"); 566#endif 567 } else if (name[0] == '%') { 568 if (is_digit(name[1])) { 569 jobno = number(name + 1); 570 if (jobno > 0 && jobno <= njobs 571 && jobtab[jobno - 1].used != 0) 572 return &jobtab[jobno - 1]; 573#if JOBS 574 } else if (name[1] == '%' && name[2] == '\0') { 575 goto currentjob; 576 } else if (name[1] == '+' && name[2] == '\0') { 577 goto currentjob; 578 } else if (name[1] == '-' && name[2] == '\0') { 579 if ((jp = getcurjob(NULL)) == NULL || 580 (jp = getcurjob(jp)) == NULL) 581 error("No previous job"); 582 return (jp); 583#endif 584 } else if (name[1] == '?') { 585 found = NULL; 586 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 587 if (jp->used && jp->nprocs > 0 588 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 589 if (found) 590 error("%s: ambiguous", name); 591 found = jp; 592 } 593 } 594 if (found != NULL) 595 return (found); 596 } else { 597 found = NULL; 598 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 599 if (jp->used && jp->nprocs > 0 600 && prefix(name + 1, jp->ps[0].cmd)) { 601 if (found) 602 error("%s: ambiguous", name); 603 found = jp; 604 } 605 } 606 if (found) 607 return found; 608 } 609 } else if (is_number(name)) { 610 pid = (pid_t)number(name); 611 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 612 if (jp->used && jp->nprocs > 0 613 && jp->ps[jp->nprocs - 1].pid == pid) 614 return jp; 615 } 616 } 617 error("No such job: %s", name); 618 /*NOTREACHED*/ 619 return NULL; 620} 621 622 623pid_t 624getjobpgrp(char *name) 625{ 626 struct job *jp; 627 628 jp = getjob(name); 629 return -jp->ps[0].pid; 630} 631 632/* 633 * Return a new job structure, 634 */ 635 636struct job * 637makejob(union node *node __unused, int nprocs) 638{ 639 int i; 640 struct job *jp; 641 642 for (i = njobs, jp = jobtab ; ; jp++) { 643 if (--i < 0) { 644 INTOFF; 645 if (njobs == 0) { 646 jobtab = ckmalloc(4 * sizeof jobtab[0]); 647#if JOBS 648 jobmru = NULL; 649#endif 650 } else { 651 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 652 memcpy(jp, jobtab, njobs * sizeof jp[0]); 653#if JOBS 654 /* Relocate `next' pointers and list head */ 655 if (jobmru != NULL) 656 jobmru = &jp[jobmru - jobtab]; 657 for (i = 0; i < njobs; i++) 658 if (jp[i].next != NULL) 659 jp[i].next = &jp[jp[i].next - 660 jobtab]; 661#endif 662 if (bgjob != NULL) 663 bgjob = &jp[bgjob - jobtab]; 664 /* Relocate `ps' pointers */ 665 for (i = 0; i < njobs; i++) 666 if (jp[i].ps == &jobtab[i].ps0) 667 jp[i].ps = &jp[i].ps0; 668 ckfree(jobtab); 669 jobtab = jp; 670 } 671 jp = jobtab + njobs; 672 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 673 INTON; 674 break; 675 } 676 if (jp->used == 0) 677 break; 678 } 679 INTOFF; 680 jp->state = 0; 681 jp->used = 1; 682 jp->changed = 0; 683 jp->nprocs = 0; 684 jp->foreground = 0; 685 jp->remembered = 0; 686#if JOBS 687 jp->jobctl = jobctl; 688 jp->next = NULL; 689#endif 690 if (nprocs > 1) { 691 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 692 } else { 693 jp->ps = &jp->ps0; 694 } 695 INTON; 696 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 697 jp - jobtab + 1)); 698 return jp; 699} 700 701#if JOBS 702static void 703setcurjob(struct job *cj) 704{ 705 struct job *jp, *prev; 706 707 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 708 if (jp == cj) { 709 if (prev != NULL) 710 prev->next = jp->next; 711 else 712 jobmru = jp->next; 713 jp->next = jobmru; 714 jobmru = cj; 715 return; 716 } 717 } 718 cj->next = jobmru; 719 jobmru = cj; 720} 721 722static void 723deljob(struct job *j) 724{ 725 struct job *jp, *prev; 726 727 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 728 if (jp == j) { 729 if (prev != NULL) 730 prev->next = jp->next; 731 else 732 jobmru = jp->next; 733 return; 734 } 735 } 736} 737 738/* 739 * Return the most recently used job that isn't `nj', and preferably one 740 * that is stopped. 741 */ 742static struct job * 743getcurjob(struct job *nj) 744{ 745 struct job *jp; 746 747 /* Try to find a stopped one.. */ 748 for (jp = jobmru; jp != NULL; jp = jp->next) 749 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 750 return (jp); 751 /* Otherwise the most recently used job that isn't `nj' */ 752 for (jp = jobmru; jp != NULL; jp = jp->next) 753 if (jp->used && jp != nj) 754 return (jp); 755 756 return (NULL); 757} 758 759#endif 760 761/* 762 * Fork of a subshell. If we are doing job control, give the subshell its 763 * own process group. Jp is a job structure that the job is to be added to. 764 * N is the command that will be evaluated by the child. Both jp and n may 765 * be NULL. The mode parameter can be one of the following: 766 * FORK_FG - Fork off a foreground process. 767 * FORK_BG - Fork off a background process. 768 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 769 * process group even if job control is on. 770 * 771 * When job control is turned off, background processes have their standard 772 * input redirected to /dev/null (except for the second and later processes 773 * in a pipeline). 774 */ 775 776pid_t 777forkshell(struct job *jp, union node *n, int mode) 778{ 779 pid_t pid; 780 pid_t pgrp; 781 782 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 783 mode)); 784 INTOFF; 785 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 786 checkzombies(); 787 flushall(); 788 pid = fork(); 789 if (pid == -1) { 790 TRACE(("Fork failed, errno=%d\n", errno)); 791 INTON; 792 error("Cannot fork: %s", strerror(errno)); 793 } 794 if (pid == 0) { 795 struct job *p; 796 int wasroot; 797 int i; 798 799 TRACE(("Child shell %d\n", (int)getpid())); 800 wasroot = rootshell; 801 rootshell = 0; 802 handler = &main_handler; 803 closescript(); 804 INTON; 805 forcelocal = 0; 806 clear_traps(); 807#if JOBS 808 jobctl = 0; /* do job control only in root shell */ 809 if (wasroot && mode != FORK_NOJOB && mflag) { 810 if (jp == NULL || jp->nprocs == 0) 811 pgrp = getpid(); 812 else 813 pgrp = jp->ps[0].pid; 814 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) { 815 /*** this causes superfluous TIOCSPGRPS ***/ 816 if (tcsetpgrp(ttyfd, pgrp) < 0) 817 error("tcsetpgrp failed, errno=%d", errno); 818 } 819 setsignal(SIGTSTP); 820 setsignal(SIGTTOU); 821 } else if (mode == FORK_BG) { 822 ignoresig(SIGINT); 823 ignoresig(SIGQUIT); 824 if ((jp == NULL || jp->nprocs == 0) && 825 ! fd0_redirected_p ()) { 826 close(0); 827 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 828 error("cannot open %s: %s", 829 _PATH_DEVNULL, strerror(errno)); 830 } 831 } 832#else 833 if (mode == FORK_BG) { 834 ignoresig(SIGINT); 835 ignoresig(SIGQUIT); 836 if ((jp == NULL || jp->nprocs == 0) && 837 ! fd0_redirected_p ()) { 838 close(0); 839 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 840 error("cannot open %s: %s", 841 _PATH_DEVNULL, strerror(errno)); 842 } 843 } 844#endif 845 INTOFF; 846 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 847 if (p->used) 848 freejob(p); 849 INTON; 850 if (wasroot && iflag) { 851 setsignal(SIGINT); 852 setsignal(SIGQUIT); 853 setsignal(SIGTERM); 854 } 855 return pid; 856 } 857 if (rootshell && mode != FORK_NOJOB && mflag) { 858 if (jp == NULL || jp->nprocs == 0) 859 pgrp = pid; 860 else 861 pgrp = jp->ps[0].pid; 862 setpgid(pid, pgrp); 863 } 864 if (mode == FORK_BG) { 865 if (bgjob != NULL && bgjob->state == JOBDONE && 866 !bgjob->remembered && !iflag) 867 freejob(bgjob); 868 backgndpid = pid; /* set $! */ 869 bgjob = jp; 870 } 871 if (jp) { 872 struct procstat *ps = &jp->ps[jp->nprocs++]; 873 ps->pid = pid; 874 ps->status = -1; 875 ps->cmd = nullstr; 876 if (iflag && rootshell && n) 877 ps->cmd = commandtext(n); 878 jp->foreground = mode == FORK_FG; 879#if JOBS 880 setcurjob(jp); 881#endif 882 } 883 INTON; 884 TRACE(("In parent shell: child = %d\n", (int)pid)); 885 return pid; 886} 887 888 889pid_t 890vforkexecshell(struct job *jp, char **argv, char **envp, const char *path, int idx, int pip[2]) 891{ 892 pid_t pid; 893 struct jmploc jmploc; 894 struct jmploc *savehandler; 895 896 TRACE(("vforkexecshell(%%%td, %s, %p) called\n", jp - jobtab, argv[0], 897 (void *)pip)); 898 INTOFF; 899 flushall(); 900 savehandler = handler; 901 pid = vfork(); 902 if (pid == -1) { 903 TRACE(("Vfork failed, errno=%d\n", errno)); 904 INTON; 905 error("Cannot fork: %s", strerror(errno)); 906 } 907 if (pid == 0) { 908 TRACE(("Child shell %d\n", (int)getpid())); 909 if (setjmp(jmploc.loc)) 910 _exit(exception == EXEXEC ? exerrno : 2); 911 if (pip != NULL) { 912 close(pip[0]); 913 if (pip[1] != 1) { 914 dup2(pip[1], 1); 915 close(pip[1]); 916 } 917 } 918 handler = &jmploc; 919 shellexec(argv, envp, path, idx); 920 } 921 handler = savehandler; 922 if (jp) { 923 struct procstat *ps = &jp->ps[jp->nprocs++]; 924 ps->pid = pid; 925 ps->status = -1; 926 ps->cmd = nullstr; 927 jp->foreground = 1; 928#if JOBS 929 setcurjob(jp); 930#endif 931 } 932 INTON; 933 TRACE(("In parent shell: child = %d\n", (int)pid)); 934 return pid; 935} 936 937 938/* 939 * Wait for job to finish. 940 * 941 * Under job control we have the problem that while a child process is 942 * running interrupts generated by the user are sent to the child but not 943 * to the shell. This means that an infinite loop started by an inter- 944 * active user may be hard to kill. With job control turned off, an 945 * interactive user may place an interactive program inside a loop. If 946 * the interactive program catches interrupts, the user doesn't want 947 * these interrupts to also abort the loop. The approach we take here 948 * is to have the shell ignore interrupt signals while waiting for a 949 * foreground process to terminate, and then send itself an interrupt 950 * signal if the child process was terminated by an interrupt signal. 951 * Unfortunately, some programs want to do a bit of cleanup and then 952 * exit on interrupt; unless these processes terminate themselves by 953 * sending a signal to themselves (instead of calling exit) they will 954 * confuse this approach. 955 */ 956 957int 958waitforjob(struct job *jp, int *origstatus) 959{ 960#if JOBS 961 pid_t mypgrp = getpgrp(); 962 int propagate_int = jp->jobctl && jp->foreground; 963#endif 964 int status; 965 int st; 966 967 INTOFF; 968 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 969 while (jp->state == 0) 970 if (dowait(1, jp) == -1) 971 dotrap(); 972#if JOBS 973 if (jp->jobctl) { 974 if (tcsetpgrp(ttyfd, mypgrp) < 0) 975 error("tcsetpgrp failed, errno=%d\n", errno); 976 } 977 if (jp->state == JOBSTOPPED) 978 setcurjob(jp); 979#endif 980 status = jp->ps[jp->nprocs - 1].status; 981 if (origstatus != NULL) 982 *origstatus = status; 983 /* convert to 8 bits */ 984 if (WIFEXITED(status)) 985 st = WEXITSTATUS(status); 986#if JOBS 987 else if (WIFSTOPPED(status)) 988 st = WSTOPSIG(status) + 128; 989#endif 990 else 991 st = WTERMSIG(status) + 128; 992 if (! JOBS || jp->state == JOBDONE) 993 freejob(jp); 994 if (int_pending()) { 995 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 996 CLEAR_PENDING_INT; 997 } 998#if JOBS 999 else if (rootshell && iflag && propagate_int && 1000 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 1001 kill(getpid(), SIGINT); 1002#endif 1003 INTON; 1004 return st; 1005} 1006 1007 1008 1009/* 1010 * Wait for a process to terminate. 1011 */ 1012 1013static pid_t 1014dowait(int block, struct job *job) 1015{ 1016 pid_t pid; 1017 int status; 1018 struct procstat *sp; 1019 struct job *jp; 1020 struct job *thisjob; 1021 int done; 1022 int stopped; 1023 int sig; 1024 int coredump; 1025 1026 in_dowait++; 1027 TRACE(("dowait(%d) called\n", block)); 1028 do { 1029 pid = waitproc(block, &status); 1030 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 1031 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) || 1032 (pid > 0 && WIFSTOPPED(status) && !iflag)); 1033 in_dowait--; 1034 if (pid == -1 && errno == ECHILD && job != NULL) 1035 job->state = JOBDONE; 1036 if (breakwaitcmd != 0) { 1037 breakwaitcmd = 0; 1038 if (pid <= 0) 1039 return -1; 1040 } 1041 if (pid <= 0) 1042 return pid; 1043 INTOFF; 1044 thisjob = NULL; 1045 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1046 if (jp->used && jp->nprocs > 0) { 1047 done = 1; 1048 stopped = 1; 1049 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1050 if (sp->pid == -1) 1051 continue; 1052 if (sp->pid == pid) { 1053 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1054 (int)pid, sp->status, 1055 status)); 1056 sp->status = status; 1057 thisjob = jp; 1058 } 1059 if (sp->status == -1) 1060 stopped = 0; 1061 else if (WIFSTOPPED(sp->status)) 1062 done = 0; 1063 } 1064 if (stopped) { /* stopped or done */ 1065 int state = done? JOBDONE : JOBSTOPPED; 1066 if (jp->state != state) { 1067 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1068 jp->state = state; 1069 if (jp != job) { 1070 if (done && !jp->remembered && 1071 !iflag && jp != bgjob) 1072 freejob(jp); 1073#if JOBS 1074 else if (done) 1075 deljob(jp); 1076#endif 1077 } 1078 } 1079 } 1080 } 1081 } 1082 INTON; 1083 if (!thisjob || thisjob->state == 0) 1084 ; 1085 else if ((!rootshell || !iflag || thisjob == job) && 1086 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1087 sig = 0; 1088 coredump = 0; 1089 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1090 if (WIFSIGNALED(sp->status)) { 1091 sig = WTERMSIG(sp->status); 1092 coredump = WCOREDUMP(sp->status); 1093 } 1094 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1095 if (sig < sys_nsig && sys_siglist[sig]) 1096 out2str(sys_siglist[sig]); 1097 else 1098 outfmt(out2, "Signal %d", sig); 1099 if (coredump) 1100 out2str(" (core dumped)"); 1101 out2c('\n'); 1102 flushout(out2); 1103 } 1104 } else { 1105 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1106 thisjob->changed = 1; 1107 } 1108 return pid; 1109} 1110 1111 1112 1113/* 1114 * Do a wait system call. If job control is compiled in, we accept 1115 * stopped processes. If block is zero, we return a value of zero 1116 * rather than blocking. 1117 */ 1118static pid_t 1119waitproc(int block, int *status) 1120{ 1121 int flags; 1122 1123#if JOBS 1124 flags = WUNTRACED; 1125#else 1126 flags = 0; 1127#endif 1128 if (block == 0) 1129 flags |= WNOHANG; 1130 return wait3(status, flags, (struct rusage *)NULL); 1131} 1132 1133/* 1134 * return 1 if there are stopped jobs, otherwise 0 1135 */ 1136int job_warning = 0; 1137int 1138stoppedjobs(void) 1139{ 1140 int jobno; 1141 struct job *jp; 1142 1143 if (job_warning) 1144 return (0); 1145 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1146 if (jp->used == 0) 1147 continue; 1148 if (jp->state == JOBSTOPPED) { 1149 out2fmt_flush("You have stopped jobs.\n"); 1150 job_warning = 2; 1151 return (1); 1152 } 1153 } 1154 1155 return (0); 1156} 1157 1158 1159static void 1160checkzombies(void) 1161{ 1162 while (njobs > 0 && dowait(0, NULL) > 0) 1163 ; 1164} 1165 1166 1167int 1168backgndpidset(void) 1169{ 1170 return backgndpid != -1; 1171} 1172 1173 1174pid_t 1175backgndpidval(void) 1176{ 1177 if (bgjob != NULL && !forcelocal) 1178 bgjob->remembered = 1; 1179 return backgndpid; 1180} 1181 1182/* 1183 * Return a string identifying a command (to be printed by the 1184 * jobs command. 1185 */ 1186 1187static char *cmdnextc; 1188static int cmdnleft; 1189#define MAXCMDTEXT 200 1190 1191char * 1192commandtext(union node *n) 1193{ 1194 char *name; 1195 1196 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1197 cmdnleft = MAXCMDTEXT - 4; 1198 cmdtxt(n); 1199 *cmdnextc = '\0'; 1200 return name; 1201} 1202 1203 1204static void 1205cmdtxt(union node *n) 1206{ 1207 union node *np; 1208 struct nodelist *lp; 1209 const char *p; 1210 int i; 1211 char s[2]; 1212 1213 if (n == NULL) 1214 return; 1215 switch (n->type) { 1216 case NSEMI: 1217 cmdtxt(n->nbinary.ch1); 1218 cmdputs("; "); 1219 cmdtxt(n->nbinary.ch2); 1220 break; 1221 case NAND: 1222 cmdtxt(n->nbinary.ch1); 1223 cmdputs(" && "); 1224 cmdtxt(n->nbinary.ch2); 1225 break; 1226 case NOR: 1227 cmdtxt(n->nbinary.ch1); 1228 cmdputs(" || "); 1229 cmdtxt(n->nbinary.ch2); 1230 break; 1231 case NPIPE: 1232 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1233 cmdtxt(lp->n); 1234 if (lp->next) 1235 cmdputs(" | "); 1236 } 1237 break; 1238 case NSUBSHELL: 1239 cmdputs("("); 1240 cmdtxt(n->nredir.n); 1241 cmdputs(")"); 1242 break; 1243 case NREDIR: 1244 case NBACKGND: 1245 cmdtxt(n->nredir.n); 1246 break; 1247 case NIF: 1248 cmdputs("if "); 1249 cmdtxt(n->nif.test); 1250 cmdputs("; then "); 1251 cmdtxt(n->nif.ifpart); 1252 cmdputs("..."); 1253 break; 1254 case NWHILE: 1255 cmdputs("while "); 1256 goto until; 1257 case NUNTIL: 1258 cmdputs("until "); 1259until: 1260 cmdtxt(n->nbinary.ch1); 1261 cmdputs("; do "); 1262 cmdtxt(n->nbinary.ch2); 1263 cmdputs("; done"); 1264 break; 1265 case NFOR: 1266 cmdputs("for "); 1267 cmdputs(n->nfor.var); 1268 cmdputs(" in ..."); 1269 break; 1270 case NCASE: 1271 cmdputs("case "); 1272 cmdputs(n->ncase.expr->narg.text); 1273 cmdputs(" in ..."); 1274 break; 1275 case NDEFUN: 1276 cmdputs(n->narg.text); 1277 cmdputs("() ..."); 1278 break; 1279 case NCMD: 1280 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1281 cmdtxt(np); 1282 if (np->narg.next) 1283 cmdputs(" "); 1284 } 1285 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1286 cmdputs(" "); 1287 cmdtxt(np); 1288 } 1289 break; 1290 case NARG: 1291 cmdputs(n->narg.text); 1292 break; 1293 case NTO: 1294 p = ">"; i = 1; goto redir; 1295 case NAPPEND: 1296 p = ">>"; i = 1; goto redir; 1297 case NTOFD: 1298 p = ">&"; i = 1; goto redir; 1299 case NCLOBBER: 1300 p = ">|"; i = 1; goto redir; 1301 case NFROM: 1302 p = "<"; i = 0; goto redir; 1303 case NFROMTO: 1304 p = "<>"; i = 0; goto redir; 1305 case NFROMFD: 1306 p = "<&"; i = 0; goto redir; 1307redir: 1308 if (n->nfile.fd != i) { 1309 s[0] = n->nfile.fd + '0'; 1310 s[1] = '\0'; 1311 cmdputs(s); 1312 } 1313 cmdputs(p); 1314 if (n->type == NTOFD || n->type == NFROMFD) { 1315 if (n->ndup.dupfd >= 0) 1316 s[0] = n->ndup.dupfd + '0'; 1317 else 1318 s[0] = '-'; 1319 s[1] = '\0'; 1320 cmdputs(s); 1321 } else { 1322 cmdtxt(n->nfile.fname); 1323 } 1324 break; 1325 case NHERE: 1326 case NXHERE: 1327 cmdputs("<<..."); 1328 break; 1329 default: 1330 cmdputs("???"); 1331 break; 1332 } 1333} 1334 1335 1336 1337static void 1338cmdputs(const char *s) 1339{ 1340 const char *p; 1341 char *q; 1342 char c; 1343 int subtype = 0; 1344 1345 if (cmdnleft <= 0) 1346 return; 1347 p = s; 1348 q = cmdnextc; 1349 while ((c = *p++) != '\0') { 1350 if (c == CTLESC) 1351 *q++ = *p++; 1352 else if (c == CTLVAR) { 1353 *q++ = '$'; 1354 if (--cmdnleft > 0) 1355 *q++ = '{'; 1356 subtype = *p++; 1357 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1358 *q++ = '#'; 1359 } else if (c == '=' && subtype != 0) { 1360 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1361 if (*q) 1362 q++; 1363 else 1364 cmdnleft++; 1365 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1366 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1367 --cmdnleft > 0) 1368 *q = q[-1], q++; 1369 subtype = 0; 1370 } else if (c == CTLENDVAR) { 1371 *q++ = '}'; 1372 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1373 cmdnleft -= 5; 1374 if (cmdnleft > 0) { 1375 *q++ = '$'; 1376 *q++ = '('; 1377 *q++ = '.'; 1378 *q++ = '.'; 1379 *q++ = '.'; 1380 *q++ = ')'; 1381 } 1382 } else if (c == CTLARI) { 1383 cmdnleft -= 2; 1384 if (cmdnleft > 0) { 1385 *q++ = '$'; 1386 *q++ = '('; 1387 *q++ = '('; 1388 } 1389 p++; 1390 } else if (c == CTLENDARI) { 1391 if (--cmdnleft > 0) { 1392 *q++ = ')'; 1393 *q++ = ')'; 1394 } 1395 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1396 cmdnleft++; /* ignore */ 1397 else 1398 *q++ = c; 1399 if (--cmdnleft <= 0) { 1400 *q++ = '.'; 1401 *q++ = '.'; 1402 *q++ = '.'; 1403 break; 1404 } 1405 } 1406 cmdnextc = q; 1407} 1408