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 35 static 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 78 static struct job *jobtab; /* array of jobs */ 79 static int njobs; /* size of array */ 80 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 81 MKINIT struct job *bgjob = NULL; /* last background process */ 82 #if JOBS 83 static struct job *jobmru; /* most recently used job list */ 84 static pid_t initialpgrp; /* pgrp of shell on invocation */ 85 #endif 86 int in_waitcmd = 0; /* are we in waitcmd()? */ 87 volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */ 88 static int ttyfd = -1; 89 90 /* mode flags for dowait */ 91 #define DOWAIT_BLOCK 0x1 /* wait until a child exits */ 92 #define DOWAIT_SIG 0x2 /* if DOWAIT_BLOCK, abort on signals */ 93 94 #if JOBS 95 static void restartjob(struct job *); 96 #endif 97 static void freejob(struct job *); 98 static struct job *getjob(char *); 99 pid_t getjobpgrp(char *); 100 static pid_t dowait(int, struct job *); 101 static void checkzombies(void); 102 static void cmdtxt(union node *); 103 static void cmdputs(const char *); 104 #if JOBS 105 static void setcurjob(struct job *); 106 static void deljob(struct job *); 107 static struct job *getcurjob(struct job *); 108 #endif 109 static void printjobcmd(struct job *); 110 static void showjob(struct job *, int); 111 112 113 /* 114 * Turn job control on and off. 115 */ 116 117 MKINIT int jobctl; 118 119 #if JOBS 120 void 121 setjobctl(int on) 122 { 123 int i; 124 125 if (on == jobctl || rootshell == 0) 126 return; 127 if (on) { 128 if (ttyfd != -1) 129 close(ttyfd); 130 if ((ttyfd = open(_PATH_TTY, O_RDWR | O_CLOEXEC)) < 0) { 131 i = 0; 132 while (i <= 2 && !isatty(i)) 133 i++; 134 if (i > 2 || 135 (ttyfd = fcntl(i, F_DUPFD_CLOEXEC, 10)) < 0) 136 goto out; 137 } 138 if (ttyfd < 10) { 139 /* 140 * Keep our TTY file descriptor out of the way of 141 * the user's redirections. 142 */ 143 if ((i = fcntl(ttyfd, F_DUPFD_CLOEXEC, 10)) < 0) { 144 close(ttyfd); 145 ttyfd = -1; 146 goto out; 147 } 148 close(ttyfd); 149 ttyfd = i; 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, (int *)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 __unused, char *argv[] __unused) 250 { 251 char *id; 252 int ch, mode; 253 254 mode = SHOWJOBS_DEFAULT; 255 while ((ch = nextopt("lps")) != '\0') { 256 switch (ch) { 257 case 'l': 258 mode = SHOWJOBS_VERBOSE; 259 break; 260 case 'p': 261 mode = SHOWJOBS_PGIDS; 262 break; 263 case 's': 264 mode = SHOWJOBS_PIDS; 265 break; 266 } 267 } 268 269 if (*argptr == NULL) 270 showjobs(0, mode); 271 else 272 while ((id = *argptr++) != NULL) 273 showjob(getjob(id), mode); 274 275 return (0); 276 } 277 278 static void 279 printjobcmd(struct job *jp) 280 { 281 struct procstat *ps; 282 int i; 283 284 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 285 out1str(ps->cmd); 286 if (i > 0) 287 out1str(" | "); 288 } 289 out1c('\n'); 290 } 291 292 static void 293 showjob(struct job *jp, int mode) 294 { 295 char s[64]; 296 char statestr[64]; 297 const char *sigstr; 298 struct procstat *ps; 299 struct job *j; 300 int col, curr, i, jobno, prev, procno; 301 char c; 302 303 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 304 jobno = jp - jobtab + 1; 305 curr = prev = 0; 306 #if JOBS 307 if ((j = getcurjob(NULL)) != NULL) { 308 curr = j - jobtab + 1; 309 if ((j = getcurjob(j)) != NULL) 310 prev = j - jobtab + 1; 311 } 312 #endif 313 ps = jp->ps + jp->nprocs - 1; 314 if (jp->state == 0) { 315 strcpy(statestr, "Running"); 316 #if JOBS 317 } else if (jp->state == JOBSTOPPED) { 318 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 319 ps--; 320 if (WIFSTOPPED(ps->status)) 321 i = WSTOPSIG(ps->status); 322 else 323 i = -1; 324 sigstr = strsignal(i); 325 if (sigstr != NULL) 326 strcpy(statestr, sigstr); 327 else 328 strcpy(statestr, "Suspended"); 329 #endif 330 } else if (WIFEXITED(ps->status)) { 331 if (WEXITSTATUS(ps->status) == 0) 332 strcpy(statestr, "Done"); 333 else 334 fmtstr(statestr, 64, "Done(%d)", 335 WEXITSTATUS(ps->status)); 336 } else { 337 i = WTERMSIG(ps->status); 338 sigstr = strsignal(i); 339 if (sigstr != NULL) 340 strcpy(statestr, sigstr); 341 else 342 strcpy(statestr, "Unknown signal"); 343 if (WCOREDUMP(ps->status)) 344 strcat(statestr, " (core dumped)"); 345 } 346 347 for (ps = jp->ps ; ; ps++) { /* for each process */ 348 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 349 out1fmt("%d\n", (int)ps->pid); 350 goto skip; 351 } 352 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 353 goto skip; 354 if (jobno == curr && ps == jp->ps) 355 c = '+'; 356 else if (jobno == prev && ps == jp->ps) 357 c = '-'; 358 else 359 c = ' '; 360 if (ps == jp->ps) 361 fmtstr(s, 64, "[%d] %c ", jobno, c); 362 else 363 fmtstr(s, 64, " %c ", c); 364 out1str(s); 365 col = strlen(s); 366 if (mode == SHOWJOBS_VERBOSE) { 367 fmtstr(s, 64, "%d ", (int)ps->pid); 368 out1str(s); 369 col += strlen(s); 370 } 371 if (ps == jp->ps) { 372 out1str(statestr); 373 col += strlen(statestr); 374 } 375 do { 376 out1c(' '); 377 col++; 378 } while (col < 30); 379 if (mode == SHOWJOBS_VERBOSE) { 380 out1str(ps->cmd); 381 out1c('\n'); 382 } else 383 printjobcmd(jp); 384 skip: if (--procno <= 0) 385 break; 386 } 387 } 388 389 /* 390 * Print a list of jobs. If "change" is nonzero, only print jobs whose 391 * statuses have changed since the last call to showjobs. 392 * 393 * If the shell is interrupted in the process of creating a job, the 394 * result may be a job structure containing zero processes. Such structures 395 * will be freed here. 396 */ 397 398 void 399 showjobs(int change, int mode) 400 { 401 int jobno; 402 struct job *jp; 403 404 TRACE(("showjobs(%d) called\n", change)); 405 checkzombies(); 406 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 407 if (! jp->used) 408 continue; 409 if (jp->nprocs == 0) { 410 freejob(jp); 411 continue; 412 } 413 if (change && ! jp->changed) 414 continue; 415 showjob(jp, mode); 416 if (mode == SHOWJOBS_DEFAULT || mode == SHOWJOBS_VERBOSE) { 417 jp->changed = 0; 418 /* Hack: discard jobs for which $! has not been 419 * referenced 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 /* 431 * Mark a job structure as unused. 432 */ 433 434 static void 435 freejob(struct job *jp) 436 { 437 struct procstat *ps; 438 int i; 439 440 INTOFF; 441 if (bgjob == jp) 442 bgjob = NULL; 443 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 444 if (ps->cmd != nullstr) 445 ckfree(ps->cmd); 446 } 447 if (jp->ps != &jp->ps0) 448 ckfree(jp->ps); 449 jp->used = 0; 450 #if JOBS 451 deljob(jp); 452 #endif 453 INTON; 454 } 455 456 457 458 int 459 waitcmd(int argc __unused, char **argv __unused) 460 { 461 struct job *job; 462 int status, retval; 463 struct job *jp; 464 465 nextopt(""); 466 if (*argptr != NULL) { 467 job = getjob(*argptr); 468 } else { 469 job = NULL; 470 } 471 472 /* 473 * Loop until a process is terminated or stopped, or a SIGINT is 474 * received. 475 */ 476 477 in_waitcmd++; 478 do { 479 if (job != NULL) { 480 if (job->state) { 481 status = job->ps[job->nprocs - 1].status; 482 if (WIFEXITED(status)) 483 retval = WEXITSTATUS(status); 484 #if JOBS 485 else if (WIFSTOPPED(status)) 486 retval = WSTOPSIG(status) + 128; 487 #endif 488 else 489 retval = WTERMSIG(status) + 128; 490 if (! iflag || ! job->changed) 491 freejob(job); 492 else { 493 job->remembered = 0; 494 if (job == bgjob) 495 bgjob = NULL; 496 } 497 in_waitcmd--; 498 return retval; 499 } 500 } else { 501 for (jp = jobtab ; jp < jobtab + njobs; jp++) 502 if (jp->used && jp->state == JOBDONE) { 503 if (! iflag || ! jp->changed) 504 freejob(jp); 505 else { 506 jp->remembered = 0; 507 if (jp == bgjob) 508 bgjob = NULL; 509 } 510 } 511 for (jp = jobtab ; ; jp++) { 512 if (jp >= jobtab + njobs) { /* no running procs */ 513 in_waitcmd--; 514 return 0; 515 } 516 if (jp->used && jp->state == 0) 517 break; 518 } 519 } 520 } while (dowait(DOWAIT_BLOCK | DOWAIT_SIG, (struct job *)NULL) != -1); 521 in_waitcmd--; 522 523 return pendingsig + 128; 524 } 525 526 527 528 int 529 jobidcmd(int argc __unused, char **argv) 530 { 531 struct job *jp; 532 int i; 533 534 jp = getjob(argv[1]); 535 for (i = 0 ; i < jp->nprocs ; ) { 536 out1fmt("%d", (int)jp->ps[i].pid); 537 out1c(++i < jp->nprocs? ' ' : '\n'); 538 } 539 return 0; 540 } 541 542 543 544 /* 545 * Convert a job name to a job structure. 546 */ 547 548 static struct job * 549 getjob(char *name) 550 { 551 int jobno; 552 struct job *found, *jp; 553 pid_t pid; 554 int i; 555 556 if (name == NULL) { 557 #if JOBS 558 currentjob: if ((jp = getcurjob(NULL)) == NULL) 559 error("No current job"); 560 return (jp); 561 #else 562 error("No current job"); 563 #endif 564 } else if (name[0] == '%') { 565 if (is_digit(name[1])) { 566 jobno = number(name + 1); 567 if (jobno > 0 && jobno <= njobs 568 && jobtab[jobno - 1].used != 0) 569 return &jobtab[jobno - 1]; 570 #if JOBS 571 } else if (name[1] == '%' && name[2] == '\0') { 572 goto currentjob; 573 } else if (name[1] == '+' && name[2] == '\0') { 574 goto currentjob; 575 } else if (name[1] == '-' && name[2] == '\0') { 576 if ((jp = getcurjob(NULL)) == NULL || 577 (jp = getcurjob(jp)) == NULL) 578 error("No previous job"); 579 return (jp); 580 #endif 581 } else if (name[1] == '?') { 582 found = NULL; 583 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 584 if (jp->used && jp->nprocs > 0 585 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 586 if (found) 587 error("%s: ambiguous", name); 588 found = jp; 589 } 590 } 591 if (found != NULL) 592 return (found); 593 } else { 594 found = NULL; 595 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 596 if (jp->used && jp->nprocs > 0 597 && prefix(name + 1, jp->ps[0].cmd)) { 598 if (found) 599 error("%s: ambiguous", name); 600 found = jp; 601 } 602 } 603 if (found) 604 return found; 605 } 606 } else if (is_number(name)) { 607 pid = (pid_t)number(name); 608 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 609 if (jp->used && jp->nprocs > 0 610 && jp->ps[jp->nprocs - 1].pid == pid) 611 return jp; 612 } 613 } 614 error("No such job: %s", name); 615 /*NOTREACHED*/ 616 return NULL; 617 } 618 619 620 pid_t 621 getjobpgrp(char *name) 622 { 623 struct job *jp; 624 625 jp = getjob(name); 626 return -jp->ps[0].pid; 627 } 628 629 /* 630 * Return a new job structure, 631 */ 632 633 struct job * 634 makejob(union node *node __unused, int nprocs) 635 { 636 int i; 637 struct job *jp; 638 639 for (i = njobs, jp = jobtab ; ; jp++) { 640 if (--i < 0) { 641 INTOFF; 642 if (njobs == 0) { 643 jobtab = ckmalloc(4 * sizeof jobtab[0]); 644 #if JOBS 645 jobmru = NULL; 646 #endif 647 } else { 648 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 649 memcpy(jp, jobtab, njobs * sizeof jp[0]); 650 #if JOBS 651 /* Relocate `next' pointers and list head */ 652 if (jobmru != NULL) 653 jobmru = &jp[jobmru - jobtab]; 654 for (i = 0; i < njobs; i++) 655 if (jp[i].next != NULL) 656 jp[i].next = &jp[jp[i].next - 657 jobtab]; 658 #endif 659 if (bgjob != NULL) 660 bgjob = &jp[bgjob - jobtab]; 661 /* Relocate `ps' pointers */ 662 for (i = 0; i < njobs; i++) 663 if (jp[i].ps == &jobtab[i].ps0) 664 jp[i].ps = &jp[i].ps0; 665 ckfree(jobtab); 666 jobtab = jp; 667 } 668 jp = jobtab + njobs; 669 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0) 670 ; 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, %s, %p) called\n", jp - jobtab, argv[0], 895 (void *)pip)); 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(DOWAIT_BLOCK | (Tflag ? DOWAIT_SIG : 0), 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 static void 1007 dummy_handler(int sig __unused) 1008 { 1009 } 1010 1011 /* 1012 * Wait for a process to terminate. 1013 */ 1014 1015 static pid_t 1016 dowait(int mode, struct job *job) 1017 { 1018 struct sigaction sa, osa; 1019 sigset_t mask, omask; 1020 pid_t pid; 1021 int status; 1022 struct procstat *sp; 1023 struct job *jp; 1024 struct job *thisjob; 1025 const char *sigstr; 1026 int done; 1027 int stopped; 1028 int sig; 1029 int coredump; 1030 int wflags; 1031 int restore_sigchld; 1032 1033 TRACE(("dowait(%d, %p) called\n", mode, job)); 1034 restore_sigchld = 0; 1035 if ((mode & DOWAIT_SIG) != 0) { 1036 sigfillset(&mask); 1037 sigprocmask(SIG_BLOCK, &mask, &omask); 1038 INTOFF; 1039 if (!issigchldtrapped()) { 1040 restore_sigchld = 1; 1041 sa.sa_handler = dummy_handler; 1042 sa.sa_flags = 0; 1043 sigemptyset(&sa.sa_mask); 1044 sigaction(SIGCHLD, &sa, &osa); 1045 } 1046 } 1047 do { 1048 #if JOBS 1049 if (iflag) 1050 wflags = WUNTRACED | WCONTINUED; 1051 else 1052 #endif 1053 wflags = 0; 1054 if ((mode & (DOWAIT_BLOCK | DOWAIT_SIG)) != DOWAIT_BLOCK) 1055 wflags |= WNOHANG; 1056 pid = wait3(&status, wflags, (struct rusage *)NULL); 1057 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 1058 if (pid == 0 && (mode & DOWAIT_SIG) != 0) { 1059 sigsuspend(&omask); 1060 pid = -1; 1061 if (int_pending()) 1062 break; 1063 } 1064 } while (pid == -1 && errno == EINTR && breakwaitcmd == 0); 1065 if (pid == -1 && errno == ECHILD && job != NULL) 1066 job->state = JOBDONE; 1067 if ((mode & DOWAIT_SIG) != 0) { 1068 if (restore_sigchld) 1069 sigaction(SIGCHLD, &osa, NULL); 1070 sigprocmask(SIG_SETMASK, &omask, NULL); 1071 INTON; 1072 } 1073 if (breakwaitcmd != 0) { 1074 breakwaitcmd = 0; 1075 if (pid <= 0) 1076 return -1; 1077 } 1078 if (pid <= 0) 1079 return pid; 1080 INTOFF; 1081 thisjob = NULL; 1082 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1083 if (jp->used && jp->nprocs > 0) { 1084 done = 1; 1085 stopped = 1; 1086 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1087 if (sp->pid == -1) 1088 continue; 1089 if (sp->pid == pid) { 1090 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1091 (int)pid, sp->status, 1092 status)); 1093 if (WIFCONTINUED(status)) { 1094 sp->status = -1; 1095 jp->state = 0; 1096 } else 1097 sp->status = status; 1098 thisjob = jp; 1099 } 1100 if (sp->status == -1) 1101 stopped = 0; 1102 else if (WIFSTOPPED(sp->status)) 1103 done = 0; 1104 } 1105 if (stopped) { /* stopped or done */ 1106 int state = done? JOBDONE : JOBSTOPPED; 1107 if (jp->state != state) { 1108 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1109 jp->state = state; 1110 if (jp != job) { 1111 if (done && !jp->remembered && 1112 !iflag && jp != bgjob) 1113 freejob(jp); 1114 #if JOBS 1115 else if (done) 1116 deljob(jp); 1117 #endif 1118 } 1119 } 1120 } 1121 } 1122 } 1123 INTON; 1124 if (!thisjob || thisjob->state == 0) 1125 ; 1126 else if ((!rootshell || !iflag || thisjob == job) && 1127 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1128 sig = 0; 1129 coredump = 0; 1130 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1131 if (WIFSIGNALED(sp->status)) { 1132 sig = WTERMSIG(sp->status); 1133 coredump = WCOREDUMP(sp->status); 1134 } 1135 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1136 sigstr = strsignal(sig); 1137 if (sigstr != NULL) 1138 out2str(sigstr); 1139 else 1140 out2str("Unknown signal"); 1141 if (coredump) 1142 out2str(" (core dumped)"); 1143 out2c('\n'); 1144 flushout(out2); 1145 } 1146 } else { 1147 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1148 thisjob->changed = 1; 1149 } 1150 return pid; 1151 } 1152 1153 1154 1155 /* 1156 * return 1 if there are stopped jobs, otherwise 0 1157 */ 1158 int job_warning = 0; 1159 int 1160 stoppedjobs(void) 1161 { 1162 int jobno; 1163 struct job *jp; 1164 1165 if (job_warning) 1166 return (0); 1167 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1168 if (jp->used == 0) 1169 continue; 1170 if (jp->state == JOBSTOPPED) { 1171 out2fmt_flush("You have stopped jobs.\n"); 1172 job_warning = 2; 1173 return (1); 1174 } 1175 } 1176 1177 return (0); 1178 } 1179 1180 1181 static void 1182 checkzombies(void) 1183 { 1184 while (njobs > 0 && dowait(0, NULL) > 0) 1185 ; 1186 } 1187 1188 1189 int 1190 backgndpidset(void) 1191 { 1192 return backgndpid != -1; 1193 } 1194 1195 1196 pid_t 1197 backgndpidval(void) 1198 { 1199 if (bgjob != NULL && !forcelocal) 1200 bgjob->remembered = 1; 1201 return backgndpid; 1202 } 1203 1204 /* 1205 * Return a string identifying a command (to be printed by the 1206 * jobs command. 1207 */ 1208 1209 static char *cmdnextc; 1210 static int cmdnleft; 1211 #define MAXCMDTEXT 200 1212 1213 char * 1214 commandtext(union node *n) 1215 { 1216 char *name; 1217 1218 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1219 cmdnleft = MAXCMDTEXT - 4; 1220 cmdtxt(n); 1221 *cmdnextc = '\0'; 1222 return name; 1223 } 1224 1225 1226 static void 1227 cmdtxt(union node *n) 1228 { 1229 union node *np; 1230 struct nodelist *lp; 1231 const char *p; 1232 int i; 1233 char s[2]; 1234 1235 if (n == NULL) 1236 return; 1237 switch (n->type) { 1238 case NSEMI: 1239 cmdtxt(n->nbinary.ch1); 1240 cmdputs("; "); 1241 cmdtxt(n->nbinary.ch2); 1242 break; 1243 case NAND: 1244 cmdtxt(n->nbinary.ch1); 1245 cmdputs(" && "); 1246 cmdtxt(n->nbinary.ch2); 1247 break; 1248 case NOR: 1249 cmdtxt(n->nbinary.ch1); 1250 cmdputs(" || "); 1251 cmdtxt(n->nbinary.ch2); 1252 break; 1253 case NPIPE: 1254 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1255 cmdtxt(lp->n); 1256 if (lp->next) 1257 cmdputs(" | "); 1258 } 1259 break; 1260 case NSUBSHELL: 1261 cmdputs("("); 1262 cmdtxt(n->nredir.n); 1263 cmdputs(")"); 1264 break; 1265 case NREDIR: 1266 case NBACKGND: 1267 cmdtxt(n->nredir.n); 1268 break; 1269 case NIF: 1270 cmdputs("if "); 1271 cmdtxt(n->nif.test); 1272 cmdputs("; then "); 1273 cmdtxt(n->nif.ifpart); 1274 cmdputs("..."); 1275 break; 1276 case NWHILE: 1277 cmdputs("while "); 1278 goto until; 1279 case NUNTIL: 1280 cmdputs("until "); 1281 until: 1282 cmdtxt(n->nbinary.ch1); 1283 cmdputs("; do "); 1284 cmdtxt(n->nbinary.ch2); 1285 cmdputs("; done"); 1286 break; 1287 case NFOR: 1288 cmdputs("for "); 1289 cmdputs(n->nfor.var); 1290 cmdputs(" in ..."); 1291 break; 1292 case NCASE: 1293 cmdputs("case "); 1294 cmdputs(n->ncase.expr->narg.text); 1295 cmdputs(" in ..."); 1296 break; 1297 case NDEFUN: 1298 cmdputs(n->narg.text); 1299 cmdputs("() ..."); 1300 break; 1301 case NNOT: 1302 cmdputs("! "); 1303 cmdtxt(n->nnot.com); 1304 break; 1305 case NCMD: 1306 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1307 cmdtxt(np); 1308 if (np->narg.next) 1309 cmdputs(" "); 1310 } 1311 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1312 cmdputs(" "); 1313 cmdtxt(np); 1314 } 1315 break; 1316 case NARG: 1317 cmdputs(n->narg.text); 1318 break; 1319 case NTO: 1320 p = ">"; i = 1; goto redir; 1321 case NAPPEND: 1322 p = ">>"; i = 1; goto redir; 1323 case NTOFD: 1324 p = ">&"; i = 1; goto redir; 1325 case NCLOBBER: 1326 p = ">|"; i = 1; goto redir; 1327 case NFROM: 1328 p = "<"; i = 0; goto redir; 1329 case NFROMTO: 1330 p = "<>"; i = 0; goto redir; 1331 case NFROMFD: 1332 p = "<&"; i = 0; goto redir; 1333 redir: 1334 if (n->nfile.fd != i) { 1335 s[0] = n->nfile.fd + '0'; 1336 s[1] = '\0'; 1337 cmdputs(s); 1338 } 1339 cmdputs(p); 1340 if (n->type == NTOFD || n->type == NFROMFD) { 1341 if (n->ndup.dupfd >= 0) 1342 s[0] = n->ndup.dupfd + '0'; 1343 else 1344 s[0] = '-'; 1345 s[1] = '\0'; 1346 cmdputs(s); 1347 } else { 1348 cmdtxt(n->nfile.fname); 1349 } 1350 break; 1351 case NHERE: 1352 case NXHERE: 1353 cmdputs("<<..."); 1354 break; 1355 default: 1356 cmdputs("???"); 1357 break; 1358 } 1359 } 1360 1361 1362 1363 static void 1364 cmdputs(const char *s) 1365 { 1366 const char *p; 1367 char *q; 1368 char c; 1369 int subtype = 0; 1370 1371 if (cmdnleft <= 0) 1372 return; 1373 p = s; 1374 q = cmdnextc; 1375 while ((c = *p++) != '\0') { 1376 if (c == CTLESC) 1377 *q++ = *p++; 1378 else if (c == CTLVAR) { 1379 *q++ = '$'; 1380 if (--cmdnleft > 0) 1381 *q++ = '{'; 1382 subtype = *p++; 1383 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1384 *q++ = '#'; 1385 } else if (c == '=' && subtype != 0) { 1386 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1387 if (*q) 1388 q++; 1389 else 1390 cmdnleft++; 1391 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1392 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1393 --cmdnleft > 0) 1394 *q = q[-1], q++; 1395 subtype = 0; 1396 } else if (c == CTLENDVAR) { 1397 *q++ = '}'; 1398 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1399 cmdnleft -= 5; 1400 if (cmdnleft > 0) { 1401 *q++ = '$'; 1402 *q++ = '('; 1403 *q++ = '.'; 1404 *q++ = '.'; 1405 *q++ = '.'; 1406 *q++ = ')'; 1407 } 1408 } else if (c == CTLARI) { 1409 cmdnleft -= 2; 1410 if (cmdnleft > 0) { 1411 *q++ = '$'; 1412 *q++ = '('; 1413 *q++ = '('; 1414 } 1415 p++; 1416 } else if (c == CTLENDARI) { 1417 if (--cmdnleft > 0) { 1418 *q++ = ')'; 1419 *q++ = ')'; 1420 } 1421 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1422 cmdnleft++; /* ignore */ 1423 else 1424 *q++ = c; 1425 if (--cmdnleft <= 0) { 1426 *q++ = '.'; 1427 *q++ = '.'; 1428 *q++ = '.'; 1429 break; 1430 } 1431 } 1432 cmdnextc = q; 1433 } 1434