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. 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 static pid_t backgndpid = -1; /* pid of last background process */ 81 static 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 static int ttyfd = -1; 87 88 /* mode flags for dowait */ 89 #define DOWAIT_BLOCK 0x1 /* wait until a child exits */ 90 #define DOWAIT_SIG 0x2 /* if DOWAIT_BLOCK, abort on signal */ 91 #define DOWAIT_SIG_TRAP 0x4 /* if DOWAIT_SIG, abort on trapped signal only */ 92 93 #if JOBS 94 static void restartjob(struct job *); 95 #endif 96 static void freejob(struct job *); 97 static int waitcmdloop(struct job *); 98 static struct job *getjob_nonotfound(const char *); 99 static struct job *getjob(const char *); 100 pid_t killjob(const char *, int); 101 static pid_t dowait(int, struct job *); 102 static void checkzombies(void); 103 static void cmdtxt(union node *); 104 static void cmdputs(const char *); 105 #if JOBS 106 static void setcurjob(struct job *); 107 static void deljob(struct job *); 108 static struct job *getcurjob(struct job *); 109 #endif 110 static void printjobcmd(struct job *); 111 static void showjob(struct job *, int); 112 113 114 /* 115 * Turn job control on and off. 116 */ 117 118 static int jobctl; 119 120 #if JOBS 121 static void 122 jobctl_notty(void) 123 { 124 if (ttyfd >= 0) { 125 close(ttyfd); 126 ttyfd = -1; 127 } 128 if (!iflag) { 129 setsignal(SIGTSTP); 130 setsignal(SIGTTOU); 131 setsignal(SIGTTIN); 132 jobctl = 1; 133 return; 134 } 135 out2fmt_flush("sh: can't access tty; job control turned off\n"); 136 mflag = 0; 137 } 138 139 void 140 setjobctl(int on) 141 { 142 int i; 143 144 if (on == jobctl || rootshell == 0) 145 return; 146 if (on) { 147 if (ttyfd != -1) 148 close(ttyfd); 149 if ((ttyfd = open(_PATH_TTY, O_RDWR | O_CLOEXEC_MAYBE)) < 0) { 150 i = 0; 151 while (i <= 2 && !isatty(i)) 152 i++; 153 if (i > 2 || 154 (ttyfd = fcntl(i, F_DUPFD_CLOEXEC_MAYBE, 10)) < 0) { 155 jobctl_notty(); 156 return; 157 } 158 } 159 if (ttyfd < 10) { 160 /* 161 * Keep our TTY file descriptor out of the way of 162 * the user's redirections. 163 */ 164 if ((i = fcntl(ttyfd, F_DUPFD_CLOEXEC_MAYBE, 10)) < 0) { 165 jobctl_notty(); 166 return; 167 } 168 close(ttyfd); 169 ttyfd = i; 170 } 171 #if !defined(O_CLOEXEC) || !defined(F_DUPFD_CLOEXEC) 172 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) { 173 close(ttyfd); 174 ttyfd = -1; 175 goto out; 176 } 177 #endif 178 do { /* while we are in the background */ 179 initialpgrp = tcgetpgrp(ttyfd); 180 if (initialpgrp < 0) { 181 #if !defined(O_CLOEXEC) || !defined(F_DUPFD_CLOEXEC) 182 out: 183 #endif 184 jobctl_notty(); 185 return; 186 } 187 if (initialpgrp != getpgrp()) { 188 if (!iflag) { 189 initialpgrp = -1; 190 jobctl_notty(); 191 return; 192 } 193 kill(0, SIGTTIN); 194 continue; 195 } 196 } while (0); 197 setsignal(SIGTSTP); 198 setsignal(SIGTTOU); 199 setsignal(SIGTTIN); 200 setpgid(0, rootpid); 201 tcsetpgrp(ttyfd, rootpid); 202 } else { /* turning job control off */ 203 setpgid(0, initialpgrp); 204 if (ttyfd >= 0) { 205 tcsetpgrp(ttyfd, initialpgrp); 206 close(ttyfd); 207 ttyfd = -1; 208 } 209 setsignal(SIGTSTP); 210 setsignal(SIGTTOU); 211 setsignal(SIGTTIN); 212 } 213 jobctl = on; 214 } 215 #endif 216 217 218 #if JOBS 219 int 220 fgcmd(int argc __unused, char **argv __unused) 221 { 222 struct job *jp; 223 pid_t pgrp; 224 int status; 225 226 nextopt(""); 227 jp = getjob(*argptr); 228 if (jp->jobctl == 0) 229 error("job not created under job control"); 230 printjobcmd(jp); 231 flushout(&output); 232 pgrp = jp->ps[0].pid; 233 if (ttyfd >= 0) 234 tcsetpgrp(ttyfd, pgrp); 235 restartjob(jp); 236 jp->foreground = 1; 237 INTOFF; 238 status = waitforjob(jp, (int *)NULL); 239 INTON; 240 return status; 241 } 242 243 244 int 245 bgcmd(int argc __unused, char **argv __unused) 246 { 247 struct job *jp; 248 249 nextopt(""); 250 do { 251 jp = getjob(*argptr); 252 if (jp->jobctl == 0) 253 error("job not created under job control"); 254 if (jp->state == JOBDONE) 255 continue; 256 restartjob(jp); 257 jp->foreground = 0; 258 out1fmt("[%td] ", jp - jobtab + 1); 259 printjobcmd(jp); 260 } while (*argptr != NULL && *++argptr != NULL); 261 return 0; 262 } 263 264 265 static void 266 restartjob(struct job *jp) 267 { 268 struct procstat *ps; 269 int i; 270 271 if (jp->state == JOBDONE) 272 return; 273 setcurjob(jp); 274 INTOFF; 275 kill(-jp->ps[0].pid, SIGCONT); 276 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 277 if (WIFSTOPPED(ps->status)) { 278 ps->status = -1; 279 jp->state = 0; 280 } 281 } 282 INTON; 283 } 284 #endif 285 286 287 int 288 jobscmd(int argc __unused, char *argv[] __unused) 289 { 290 char *id; 291 int ch, mode; 292 293 mode = SHOWJOBS_DEFAULT; 294 while ((ch = nextopt("lps")) != '\0') { 295 switch (ch) { 296 case 'l': 297 mode = SHOWJOBS_VERBOSE; 298 break; 299 case 'p': 300 mode = SHOWJOBS_PGIDS; 301 break; 302 case 's': 303 mode = SHOWJOBS_PIDS; 304 break; 305 } 306 } 307 308 if (*argptr == NULL) 309 showjobs(0, mode); 310 else 311 while ((id = *argptr++) != NULL) 312 showjob(getjob(id), mode); 313 314 return (0); 315 } 316 317 static void 318 printjobcmd(struct job *jp) 319 { 320 struct procstat *ps; 321 int i; 322 323 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 324 out1str(ps->cmd); 325 if (i > 0) 326 out1str(" | "); 327 } 328 out1c('\n'); 329 } 330 331 static void 332 showjob(struct job *jp, int mode) 333 { 334 char s[64]; 335 char statestr[64]; 336 const char *sigstr; 337 struct procstat *ps; 338 struct job *j; 339 int col, curr, i, jobno, prev, procno; 340 char c; 341 342 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs; 343 jobno = jp - jobtab + 1; 344 curr = prev = 0; 345 #if JOBS 346 if ((j = getcurjob(NULL)) != NULL) { 347 curr = j - jobtab + 1; 348 if ((j = getcurjob(j)) != NULL) 349 prev = j - jobtab + 1; 350 } 351 #endif 352 ps = jp->ps + jp->nprocs - 1; 353 if (jp->state == 0) { 354 strcpy(statestr, "Running"); 355 #if JOBS 356 } else if (jp->state == JOBSTOPPED) { 357 while (!WIFSTOPPED(ps->status) && ps > jp->ps) 358 ps--; 359 if (WIFSTOPPED(ps->status)) 360 i = WSTOPSIG(ps->status); 361 else 362 i = -1; 363 sigstr = strsignal(i); 364 if (sigstr != NULL) 365 strcpy(statestr, sigstr); 366 else 367 strcpy(statestr, "Suspended"); 368 #endif 369 } else if (WIFEXITED(ps->status)) { 370 if (WEXITSTATUS(ps->status) == 0) 371 strcpy(statestr, "Done"); 372 else 373 fmtstr(statestr, 64, "Done(%d)", 374 WEXITSTATUS(ps->status)); 375 } else { 376 i = WTERMSIG(ps->status); 377 sigstr = strsignal(i); 378 if (sigstr != NULL) 379 strcpy(statestr, sigstr); 380 else 381 strcpy(statestr, "Unknown signal"); 382 if (WCOREDUMP(ps->status)) 383 strcat(statestr, " (core dumped)"); 384 } 385 386 for (ps = jp->ps ; procno > 0 ; ps++, procno--) { /* for each process */ 387 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) { 388 out1fmt("%d\n", (int)ps->pid); 389 continue; 390 } 391 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps) 392 continue; 393 if (jobno == curr && ps == jp->ps) 394 c = '+'; 395 else if (jobno == prev && ps == jp->ps) 396 c = '-'; 397 else 398 c = ' '; 399 if (ps == jp->ps) 400 fmtstr(s, 64, "[%d] %c ", jobno, c); 401 else 402 fmtstr(s, 64, " %c ", c); 403 out1str(s); 404 col = strlen(s); 405 if (mode == SHOWJOBS_VERBOSE) { 406 fmtstr(s, 64, "%d ", (int)ps->pid); 407 out1str(s); 408 col += strlen(s); 409 } 410 if (ps == jp->ps) { 411 out1str(statestr); 412 col += strlen(statestr); 413 } 414 do { 415 out1c(' '); 416 col++; 417 } while (col < 30); 418 if (mode == SHOWJOBS_VERBOSE) { 419 out1str(ps->cmd); 420 out1c('\n'); 421 } else 422 printjobcmd(jp); 423 } 424 } 425 426 /* 427 * Print a list of jobs. If "change" is nonzero, only print jobs whose 428 * statuses have changed since the last call to showjobs. 429 * 430 * If the shell is interrupted in the process of creating a job, the 431 * result may be a job structure containing zero processes. Such structures 432 * will be freed here. 433 */ 434 435 void 436 showjobs(int change, int mode) 437 { 438 int jobno; 439 struct job *jp; 440 441 TRACE(("showjobs(%d) called\n", change)); 442 checkzombies(); 443 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 444 if (! jp->used) 445 continue; 446 if (jp->nprocs == 0) { 447 freejob(jp); 448 continue; 449 } 450 if (change && ! jp->changed) 451 continue; 452 showjob(jp, mode); 453 if (mode == SHOWJOBS_DEFAULT || mode == SHOWJOBS_VERBOSE) { 454 jp->changed = 0; 455 /* Hack: discard jobs for which $! has not been 456 * referenced in interactive mode when they terminate. 457 */ 458 if (jp->state == JOBDONE && !jp->remembered && 459 (iflag || jp != bgjob)) { 460 freejob(jp); 461 } 462 } 463 } 464 } 465 466 467 /* 468 * Mark a job structure as unused. 469 */ 470 471 static void 472 freejob(struct job *jp) 473 { 474 struct procstat *ps; 475 int i; 476 477 INTOFF; 478 if (bgjob == jp) 479 bgjob = NULL; 480 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) { 481 if (ps->cmd != nullstr) 482 ckfree(ps->cmd); 483 } 484 if (jp->ps != &jp->ps0) 485 ckfree(jp->ps); 486 jp->used = 0; 487 #if JOBS 488 deljob(jp); 489 #endif 490 INTON; 491 } 492 493 494 495 int 496 waitcmd(int argc __unused, char **argv __unused) 497 { 498 struct job *job; 499 int retval; 500 501 nextopt(""); 502 if (*argptr == NULL) 503 return (waitcmdloop(NULL)); 504 505 do { 506 job = getjob_nonotfound(*argptr); 507 if (job == NULL) 508 retval = 127; 509 else 510 retval = waitcmdloop(job); 511 argptr++; 512 } while (*argptr != NULL); 513 514 return (retval); 515 } 516 517 static int 518 waitcmdloop(struct job *job) 519 { 520 int status, retval, sig; 521 struct job *jp; 522 523 /* 524 * Loop until a process is terminated or stopped, or a SIGINT is 525 * received. 526 */ 527 528 do { 529 if (job != NULL) { 530 if (job->state == JOBDONE) { 531 status = job->ps[job->nprocs - 1].status; 532 if (WIFEXITED(status)) 533 retval = WEXITSTATUS(status); 534 else 535 retval = WTERMSIG(status) + 128; 536 if (! iflag || ! job->changed) 537 freejob(job); 538 else { 539 job->remembered = 0; 540 if (job == bgjob) 541 bgjob = NULL; 542 } 543 return retval; 544 } 545 } else { 546 for (jp = jobtab ; jp < jobtab + njobs; jp++) 547 if (jp->used && jp->state == JOBDONE) { 548 if (! iflag || ! jp->changed) 549 freejob(jp); 550 else { 551 jp->remembered = 0; 552 if (jp == bgjob) 553 bgjob = NULL; 554 } 555 } 556 for (jp = jobtab ; ; jp++) { 557 if (jp >= jobtab + njobs) { /* no running procs */ 558 return 0; 559 } 560 if (jp->used && jp->state == 0) 561 break; 562 } 563 } 564 } while (dowait(DOWAIT_BLOCK | DOWAIT_SIG, (struct job *)NULL) != -1); 565 566 sig = pendingsig_waitcmd; 567 pendingsig_waitcmd = 0; 568 return sig + 128; 569 } 570 571 572 573 int 574 jobidcmd(int argc __unused, char **argv __unused) 575 { 576 struct job *jp; 577 int i; 578 579 nextopt(""); 580 jp = getjob(*argptr); 581 for (i = 0 ; i < jp->nprocs ; ) { 582 out1fmt("%d", (int)jp->ps[i].pid); 583 out1c(++i < jp->nprocs? ' ' : '\n'); 584 } 585 return 0; 586 } 587 588 589 590 /* 591 * Convert a job name to a job structure. 592 */ 593 594 static struct job * 595 getjob_nonotfound(const char *name) 596 { 597 int jobno; 598 struct job *found, *jp; 599 size_t namelen; 600 pid_t pid; 601 int i; 602 603 if (name == NULL) { 604 #if JOBS 605 name = "%+"; 606 #else 607 error("No current job"); 608 #endif 609 } 610 if (name[0] == '%') { 611 if (is_digit(name[1])) { 612 jobno = number(name + 1); 613 if (jobno > 0 && jobno <= njobs 614 && jobtab[jobno - 1].used != 0) 615 return &jobtab[jobno - 1]; 616 #if JOBS 617 } else if ((name[1] == '%' || name[1] == '+') && 618 name[2] == '\0') { 619 if ((jp = getcurjob(NULL)) == NULL) 620 error("No current job"); 621 return (jp); 622 } else if (name[1] == '-' && name[2] == '\0') { 623 if ((jp = getcurjob(NULL)) == NULL || 624 (jp = getcurjob(jp)) == NULL) 625 error("No previous job"); 626 return (jp); 627 #endif 628 } else if (name[1] == '?') { 629 found = NULL; 630 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 631 if (jp->used && jp->nprocs > 0 632 && strstr(jp->ps[0].cmd, name + 2) != NULL) { 633 if (found) 634 error("%s: ambiguous", name); 635 found = jp; 636 } 637 } 638 if (found != NULL) 639 return (found); 640 } else { 641 namelen = strlen(name); 642 found = NULL; 643 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 644 if (jp->used && jp->nprocs > 0 645 && strncmp(jp->ps[0].cmd, name + 1, 646 namelen - 1) == 0) { 647 if (found) 648 error("%s: ambiguous", name); 649 found = jp; 650 } 651 } 652 if (found) 653 return found; 654 } 655 } else if (is_number(name)) { 656 pid = (pid_t)number(name); 657 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 658 if (jp->used && jp->nprocs > 0 659 && jp->ps[jp->nprocs - 1].pid == pid) 660 return jp; 661 } 662 } 663 return NULL; 664 } 665 666 667 static struct job * 668 getjob(const char *name) 669 { 670 struct job *jp; 671 672 jp = getjob_nonotfound(name); 673 if (jp == NULL) 674 error("No such job: %s", name); 675 return (jp); 676 } 677 678 679 int 680 killjob(const char *name, int sig) 681 { 682 struct job *jp; 683 int i, ret; 684 685 jp = getjob(name); 686 if (jp->state == JOBDONE) 687 return 0; 688 if (jp->jobctl) 689 return kill(-jp->ps[0].pid, sig); 690 ret = -1; 691 errno = ESRCH; 692 for (i = 0; i < jp->nprocs; i++) 693 if (jp->ps[i].status == -1 || WIFSTOPPED(jp->ps[i].status)) { 694 if (kill(jp->ps[i].pid, sig) == 0) 695 ret = 0; 696 } else 697 ret = 0; 698 return ret; 699 } 700 701 /* 702 * Return a new job structure, 703 */ 704 705 struct job * 706 makejob(union node *node __unused, int nprocs) 707 { 708 int i; 709 struct job *jp; 710 711 for (i = njobs, jp = jobtab ; ; jp++) { 712 if (--i < 0) { 713 INTOFF; 714 if (njobs == 0) { 715 jobtab = ckmalloc(4 * sizeof jobtab[0]); 716 #if JOBS 717 jobmru = NULL; 718 #endif 719 } else { 720 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 721 memcpy(jp, jobtab, njobs * sizeof jp[0]); 722 #if JOBS 723 /* Relocate `next' pointers and list head */ 724 if (jobmru != NULL) 725 jobmru = &jp[jobmru - jobtab]; 726 for (i = 0; i < njobs; i++) 727 if (jp[i].next != NULL) 728 jp[i].next = &jp[jp[i].next - 729 jobtab]; 730 #endif 731 if (bgjob != NULL) 732 bgjob = &jp[bgjob - jobtab]; 733 /* Relocate `ps' pointers */ 734 for (i = 0; i < njobs; i++) 735 if (jp[i].ps == &jobtab[i].ps0) 736 jp[i].ps = &jp[i].ps0; 737 ckfree(jobtab); 738 jobtab = jp; 739 } 740 jp = jobtab + njobs; 741 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0) 742 ; 743 INTON; 744 break; 745 } 746 if (jp->used == 0) 747 break; 748 } 749 INTOFF; 750 jp->state = 0; 751 jp->used = 1; 752 jp->changed = 0; 753 jp->nprocs = 0; 754 jp->foreground = 0; 755 jp->remembered = 0; 756 #if JOBS 757 jp->jobctl = jobctl; 758 jp->next = NULL; 759 #endif 760 if (nprocs > 1) { 761 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 762 } else { 763 jp->ps = &jp->ps0; 764 } 765 INTON; 766 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs, 767 jp - jobtab + 1)); 768 return jp; 769 } 770 771 #if JOBS 772 static void 773 setcurjob(struct job *cj) 774 { 775 struct job *jp, *prev; 776 777 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 778 if (jp == cj) { 779 if (prev != NULL) 780 prev->next = jp->next; 781 else 782 jobmru = jp->next; 783 jp->next = jobmru; 784 jobmru = cj; 785 return; 786 } 787 } 788 cj->next = jobmru; 789 jobmru = cj; 790 } 791 792 static void 793 deljob(struct job *j) 794 { 795 struct job *jp, *prev; 796 797 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) { 798 if (jp == j) { 799 if (prev != NULL) 800 prev->next = jp->next; 801 else 802 jobmru = jp->next; 803 return; 804 } 805 } 806 } 807 808 /* 809 * Return the most recently used job that isn't `nj', and preferably one 810 * that is stopped. 811 */ 812 static struct job * 813 getcurjob(struct job *nj) 814 { 815 struct job *jp; 816 817 /* Try to find a stopped one.. */ 818 for (jp = jobmru; jp != NULL; jp = jp->next) 819 if (jp->used && jp != nj && jp->state == JOBSTOPPED) 820 return (jp); 821 /* Otherwise the most recently used job that isn't `nj' */ 822 for (jp = jobmru; jp != NULL; jp = jp->next) 823 if (jp->used && jp != nj) 824 return (jp); 825 826 return (NULL); 827 } 828 829 #endif 830 831 /* 832 * Fork of a subshell. If we are doing job control, give the subshell its 833 * own process group. Jp is a job structure that the job is to be added to. 834 * N is the command that will be evaluated by the child. Both jp and n may 835 * be NULL. The mode parameter can be one of the following: 836 * FORK_FG - Fork off a foreground process. 837 * FORK_BG - Fork off a background process. 838 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 839 * process group even if job control is on. 840 * 841 * When job control is turned off, background processes have their standard 842 * input redirected to /dev/null (except for the second and later processes 843 * in a pipeline). 844 */ 845 846 pid_t 847 forkshell(struct job *jp, union node *n, int mode) 848 { 849 pid_t pid; 850 pid_t pgrp; 851 852 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n, 853 mode)); 854 INTOFF; 855 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0)) 856 checkzombies(); 857 flushall(); 858 pid = fork(); 859 if (pid == -1) { 860 TRACE(("Fork failed, errno=%d\n", errno)); 861 INTON; 862 error("Cannot fork: %s", strerror(errno)); 863 } 864 if (pid == 0) { 865 struct job *p; 866 int wasroot; 867 int i; 868 869 TRACE(("Child shell %d\n", (int)getpid())); 870 wasroot = rootshell; 871 rootshell = 0; 872 handler = &main_handler; 873 closescript(); 874 INTON; 875 forcelocal = 0; 876 clear_traps(); 877 #if JOBS 878 jobctl = 0; /* do job control only in root shell */ 879 if (wasroot && mode != FORK_NOJOB && mflag) { 880 if (jp == NULL || jp->nprocs == 0) 881 pgrp = getpid(); 882 else 883 pgrp = jp->ps[0].pid; 884 if (setpgid(0, pgrp) == 0 && mode == FORK_FG && 885 ttyfd >= 0) { 886 /*** this causes superfluous TIOCSPGRPS ***/ 887 if (tcsetpgrp(ttyfd, pgrp) < 0) 888 error("tcsetpgrp failed, errno=%d", errno); 889 } 890 setsignal(SIGTSTP); 891 setsignal(SIGTTOU); 892 } else if (mode == FORK_BG) { 893 ignoresig(SIGINT); 894 ignoresig(SIGQUIT); 895 if ((jp == NULL || jp->nprocs == 0) && 896 ! fd0_redirected_p ()) { 897 close(0); 898 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 899 error("cannot open %s: %s", 900 _PATH_DEVNULL, strerror(errno)); 901 } 902 } 903 #else 904 if (mode == FORK_BG) { 905 ignoresig(SIGINT); 906 ignoresig(SIGQUIT); 907 if ((jp == NULL || jp->nprocs == 0) && 908 ! fd0_redirected_p ()) { 909 close(0); 910 if (open(_PATH_DEVNULL, O_RDONLY) != 0) 911 error("cannot open %s: %s", 912 _PATH_DEVNULL, strerror(errno)); 913 } 914 } 915 #endif 916 INTOFF; 917 for (i = njobs, p = jobtab ; --i >= 0 ; p++) 918 if (p->used) 919 freejob(p); 920 INTON; 921 if (wasroot && iflag) { 922 setsignal(SIGINT); 923 setsignal(SIGQUIT); 924 setsignal(SIGTERM); 925 } 926 return pid; 927 } 928 if (rootshell && mode != FORK_NOJOB && mflag) { 929 if (jp == NULL || jp->nprocs == 0) 930 pgrp = pid; 931 else 932 pgrp = jp->ps[0].pid; 933 setpgid(pid, pgrp); 934 } 935 if (mode == FORK_BG) { 936 if (bgjob != NULL && bgjob->state == JOBDONE && 937 !bgjob->remembered && !iflag) 938 freejob(bgjob); 939 backgndpid = pid; /* set $! */ 940 bgjob = jp; 941 } 942 if (jp) { 943 struct procstat *ps = &jp->ps[jp->nprocs++]; 944 ps->pid = pid; 945 ps->status = -1; 946 ps->cmd = nullstr; 947 if (iflag && rootshell && n) 948 ps->cmd = commandtext(n); 949 jp->foreground = mode == FORK_FG; 950 #if JOBS 951 setcurjob(jp); 952 #endif 953 } 954 INTON; 955 TRACE(("In parent shell: child = %d\n", (int)pid)); 956 return pid; 957 } 958 959 960 pid_t 961 vforkexecshell(struct job *jp, char **argv, char **envp, const char *path, int idx, int pip[2]) 962 { 963 pid_t pid; 964 struct jmploc jmploc; 965 struct jmploc *savehandler; 966 967 TRACE(("vforkexecshell(%%%td, %s, %p) called\n", jp - jobtab, argv[0], 968 (void *)pip)); 969 INTOFF; 970 flushall(); 971 savehandler = handler; 972 pid = vfork(); 973 if (pid == -1) { 974 TRACE(("Vfork failed, errno=%d\n", errno)); 975 INTON; 976 error("Cannot fork: %s", strerror(errno)); 977 } 978 if (pid == 0) { 979 TRACE(("Child shell %d\n", (int)getpid())); 980 if (setjmp(jmploc.loc)) 981 _exit(exception == EXEXEC ? exerrno : 2); 982 if (pip != NULL) { 983 close(pip[0]); 984 if (pip[1] != 1) { 985 dup2(pip[1], 1); 986 close(pip[1]); 987 } 988 } 989 handler = &jmploc; 990 shellexec(argv, envp, path, idx); 991 } 992 handler = savehandler; 993 if (jp) { 994 struct procstat *ps = &jp->ps[jp->nprocs++]; 995 ps->pid = pid; 996 ps->status = -1; 997 ps->cmd = nullstr; 998 jp->foreground = 1; 999 #if JOBS 1000 setcurjob(jp); 1001 #endif 1002 } 1003 INTON; 1004 TRACE(("In parent shell: child = %d\n", (int)pid)); 1005 return pid; 1006 } 1007 1008 1009 /* 1010 * Wait for job to finish. 1011 * 1012 * Under job control we have the problem that while a child process is 1013 * running interrupts generated by the user are sent to the child but not 1014 * to the shell. This means that an infinite loop started by an inter- 1015 * active user may be hard to kill. With job control turned off, an 1016 * interactive user may place an interactive program inside a loop. If 1017 * the interactive program catches interrupts, the user doesn't want 1018 * these interrupts to also abort the loop. The approach we take here 1019 * is to have the shell ignore interrupt signals while waiting for a 1020 * foreground process to terminate, and then send itself an interrupt 1021 * signal if the child process was terminated by an interrupt signal. 1022 * Unfortunately, some programs want to do a bit of cleanup and then 1023 * exit on interrupt; unless these processes terminate themselves by 1024 * sending a signal to themselves (instead of calling exit) they will 1025 * confuse this approach. 1026 */ 1027 1028 int 1029 waitforjob(struct job *jp, int *origstatus) 1030 { 1031 #if JOBS 1032 int propagate_int = jp->jobctl && jp->foreground; 1033 #endif 1034 int status; 1035 int st; 1036 1037 INTOFF; 1038 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1)); 1039 while (jp->state == 0) 1040 if (dowait(DOWAIT_BLOCK | (Tflag ? DOWAIT_SIG | 1041 DOWAIT_SIG_TRAP : 0), jp) == -1) 1042 dotrap(); 1043 #if JOBS 1044 if (jp->jobctl) { 1045 if (ttyfd >= 0 && tcsetpgrp(ttyfd, rootpid) < 0) 1046 error("tcsetpgrp failed, errno=%d\n", errno); 1047 } 1048 if (jp->state == JOBSTOPPED) 1049 setcurjob(jp); 1050 #endif 1051 status = jp->ps[jp->nprocs - 1].status; 1052 if (origstatus != NULL) 1053 *origstatus = status; 1054 /* convert to 8 bits */ 1055 if (WIFEXITED(status)) 1056 st = WEXITSTATUS(status); 1057 #if JOBS 1058 else if (WIFSTOPPED(status)) 1059 st = WSTOPSIG(status) + 128; 1060 #endif 1061 else 1062 st = WTERMSIG(status) + 128; 1063 if (! JOBS || jp->state == JOBDONE) 1064 freejob(jp); 1065 if (int_pending()) { 1066 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT) 1067 CLEAR_PENDING_INT; 1068 } 1069 #if JOBS 1070 else if (rootshell && propagate_int && 1071 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 1072 kill(getpid(), SIGINT); 1073 #endif 1074 INTON; 1075 return st; 1076 } 1077 1078 1079 static void 1080 dummy_handler(int sig __unused) 1081 { 1082 } 1083 1084 /* 1085 * Wait for a process to terminate. 1086 */ 1087 1088 static pid_t 1089 dowait(int mode, struct job *job) 1090 { 1091 struct sigaction sa, osa; 1092 sigset_t mask, omask; 1093 pid_t pid; 1094 int status; 1095 struct procstat *sp; 1096 struct job *jp; 1097 struct job *thisjob; 1098 const char *sigstr; 1099 int done; 1100 int stopped; 1101 int sig; 1102 int coredump; 1103 int wflags; 1104 int restore_sigchld; 1105 1106 TRACE(("dowait(%d, %p) called\n", mode, job)); 1107 restore_sigchld = 0; 1108 if ((mode & DOWAIT_SIG) != 0) { 1109 sigfillset(&mask); 1110 sigprocmask(SIG_BLOCK, &mask, &omask); 1111 INTOFF; 1112 if (!issigchldtrapped()) { 1113 restore_sigchld = 1; 1114 sa.sa_handler = dummy_handler; 1115 sa.sa_flags = 0; 1116 sigemptyset(&sa.sa_mask); 1117 sigaction(SIGCHLD, &sa, &osa); 1118 } 1119 } 1120 do { 1121 #if JOBS 1122 if (iflag) 1123 wflags = WUNTRACED | WCONTINUED; 1124 else 1125 #endif 1126 wflags = 0; 1127 if ((mode & (DOWAIT_BLOCK | DOWAIT_SIG)) != DOWAIT_BLOCK) 1128 wflags |= WNOHANG; 1129 pid = wait3(&status, wflags, (struct rusage *)NULL); 1130 TRACE(("wait returns %d, status=%d\n", (int)pid, status)); 1131 if (pid == 0 && (mode & DOWAIT_SIG) != 0) { 1132 pid = -1; 1133 if (((mode & DOWAIT_SIG_TRAP) != 0 ? 1134 pendingsig : pendingsig_waitcmd) != 0) { 1135 errno = EINTR; 1136 break; 1137 } 1138 sigsuspend(&omask); 1139 if (int_pending()) 1140 break; 1141 } 1142 } while (pid == -1 && errno == EINTR); 1143 if (pid == -1 && errno == ECHILD && job != NULL) 1144 job->state = JOBDONE; 1145 if ((mode & DOWAIT_SIG) != 0) { 1146 if (restore_sigchld) 1147 sigaction(SIGCHLD, &osa, NULL); 1148 sigprocmask(SIG_SETMASK, &omask, NULL); 1149 INTON; 1150 } 1151 if (pid <= 0) 1152 return pid; 1153 INTOFF; 1154 thisjob = NULL; 1155 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1156 if (jp->used && jp->nprocs > 0) { 1157 done = 1; 1158 stopped = 1; 1159 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1160 if (sp->pid == -1) 1161 continue; 1162 if (sp->pid == pid && (sp->status == -1 || 1163 WIFSTOPPED(sp->status))) { 1164 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n", 1165 (int)pid, sp->status, 1166 status)); 1167 if (WIFCONTINUED(status)) { 1168 sp->status = -1; 1169 jp->state = 0; 1170 } else 1171 sp->status = status; 1172 thisjob = jp; 1173 } 1174 if (sp->status == -1) 1175 stopped = 0; 1176 else if (WIFSTOPPED(sp->status)) 1177 done = 0; 1178 } 1179 if (stopped) { /* stopped or done */ 1180 int state = done? JOBDONE : JOBSTOPPED; 1181 if (jp->state != state) { 1182 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1183 jp->state = state; 1184 if (jp != job) { 1185 if (done && !jp->remembered && 1186 !iflag && jp != bgjob) 1187 freejob(jp); 1188 #if JOBS 1189 else if (done) 1190 deljob(jp); 1191 #endif 1192 } 1193 } 1194 } 1195 } 1196 } 1197 INTON; 1198 if (!thisjob || thisjob->state == 0) 1199 ; 1200 else if ((!rootshell || !iflag || thisjob == job) && 1201 thisjob->foreground && thisjob->state != JOBSTOPPED) { 1202 sig = 0; 1203 coredump = 0; 1204 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++) 1205 if (WIFSIGNALED(sp->status)) { 1206 sig = WTERMSIG(sp->status); 1207 coredump = WCOREDUMP(sp->status); 1208 } 1209 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) { 1210 sigstr = strsignal(sig); 1211 if (sigstr != NULL) 1212 out2str(sigstr); 1213 else 1214 out2str("Unknown signal"); 1215 if (coredump) 1216 out2str(" (core dumped)"); 1217 out2c('\n'); 1218 flushout(out2); 1219 } 1220 } else { 1221 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job)); 1222 thisjob->changed = 1; 1223 } 1224 return pid; 1225 } 1226 1227 1228 1229 /* 1230 * return 1 if there are stopped jobs, otherwise 0 1231 */ 1232 int job_warning = 0; 1233 int 1234 stoppedjobs(void) 1235 { 1236 int jobno; 1237 struct job *jp; 1238 1239 if (job_warning) 1240 return (0); 1241 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1242 if (jp->used == 0) 1243 continue; 1244 if (jp->state == JOBSTOPPED) { 1245 out2fmt_flush("You have stopped jobs.\n"); 1246 job_warning = 2; 1247 return (1); 1248 } 1249 } 1250 1251 return (0); 1252 } 1253 1254 1255 static void 1256 checkzombies(void) 1257 { 1258 while (njobs > 0 && dowait(0, NULL) > 0) 1259 ; 1260 } 1261 1262 1263 int 1264 backgndpidset(void) 1265 { 1266 return backgndpid != -1; 1267 } 1268 1269 1270 pid_t 1271 backgndpidval(void) 1272 { 1273 if (bgjob != NULL && !forcelocal) 1274 bgjob->remembered = 1; 1275 return backgndpid; 1276 } 1277 1278 /* 1279 * Return a string identifying a command (to be printed by the 1280 * jobs command. 1281 */ 1282 1283 static char *cmdnextc; 1284 static int cmdnleft; 1285 #define MAXCMDTEXT 200 1286 1287 char * 1288 commandtext(union node *n) 1289 { 1290 char *name; 1291 1292 cmdnextc = name = ckmalloc(MAXCMDTEXT); 1293 cmdnleft = MAXCMDTEXT - 4; 1294 cmdtxt(n); 1295 *cmdnextc = '\0'; 1296 return name; 1297 } 1298 1299 1300 static void 1301 cmdtxtdogroup(union node *n) 1302 { 1303 cmdputs("; do "); 1304 cmdtxt(n); 1305 cmdputs("; done"); 1306 } 1307 1308 1309 static void 1310 cmdtxtredir(union node *n, const char *op, int deffd) 1311 { 1312 char s[2]; 1313 1314 if (n->nfile.fd != deffd) { 1315 s[0] = n->nfile.fd + '0'; 1316 s[1] = '\0'; 1317 cmdputs(s); 1318 } 1319 cmdputs(op); 1320 if (n->type == NTOFD || n->type == NFROMFD) { 1321 if (n->ndup.dupfd >= 0) 1322 s[0] = n->ndup.dupfd + '0'; 1323 else 1324 s[0] = '-'; 1325 s[1] = '\0'; 1326 cmdputs(s); 1327 } else { 1328 cmdtxt(n->nfile.fname); 1329 } 1330 } 1331 1332 1333 static void 1334 cmdtxt(union node *n) 1335 { 1336 union node *np; 1337 struct nodelist *lp; 1338 1339 if (n == NULL) 1340 return; 1341 switch (n->type) { 1342 case NSEMI: 1343 cmdtxt(n->nbinary.ch1); 1344 cmdputs("; "); 1345 cmdtxt(n->nbinary.ch2); 1346 break; 1347 case NAND: 1348 cmdtxt(n->nbinary.ch1); 1349 cmdputs(" && "); 1350 cmdtxt(n->nbinary.ch2); 1351 break; 1352 case NOR: 1353 cmdtxt(n->nbinary.ch1); 1354 cmdputs(" || "); 1355 cmdtxt(n->nbinary.ch2); 1356 break; 1357 case NPIPE: 1358 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1359 cmdtxt(lp->n); 1360 if (lp->next) 1361 cmdputs(" | "); 1362 } 1363 break; 1364 case NSUBSHELL: 1365 cmdputs("("); 1366 cmdtxt(n->nredir.n); 1367 cmdputs(")"); 1368 break; 1369 case NREDIR: 1370 case NBACKGND: 1371 cmdtxt(n->nredir.n); 1372 break; 1373 case NIF: 1374 cmdputs("if "); 1375 cmdtxt(n->nif.test); 1376 cmdputs("; then "); 1377 cmdtxt(n->nif.ifpart); 1378 cmdputs("..."); 1379 break; 1380 case NWHILE: 1381 cmdputs("while "); 1382 cmdtxt(n->nbinary.ch1); 1383 cmdtxtdogroup(n->nbinary.ch2); 1384 break; 1385 case NUNTIL: 1386 cmdputs("until "); 1387 cmdtxt(n->nbinary.ch1); 1388 cmdtxtdogroup(n->nbinary.ch2); 1389 break; 1390 case NFOR: 1391 cmdputs("for "); 1392 cmdputs(n->nfor.var); 1393 cmdputs(" in ..."); 1394 break; 1395 case NCASE: 1396 cmdputs("case "); 1397 cmdputs(n->ncase.expr->narg.text); 1398 cmdputs(" in ..."); 1399 break; 1400 case NDEFUN: 1401 cmdputs(n->narg.text); 1402 cmdputs("() ..."); 1403 break; 1404 case NNOT: 1405 cmdputs("! "); 1406 cmdtxt(n->nnot.com); 1407 break; 1408 case NCMD: 1409 for (np = n->ncmd.args ; np ; np = np->narg.next) { 1410 cmdtxt(np); 1411 if (np->narg.next) 1412 cmdputs(" "); 1413 } 1414 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) { 1415 cmdputs(" "); 1416 cmdtxt(np); 1417 } 1418 break; 1419 case NARG: 1420 cmdputs(n->narg.text); 1421 break; 1422 case NTO: 1423 cmdtxtredir(n, ">", 1); 1424 break; 1425 case NAPPEND: 1426 cmdtxtredir(n, ">>", 1); 1427 break; 1428 case NTOFD: 1429 cmdtxtredir(n, ">&", 1); 1430 break; 1431 case NCLOBBER: 1432 cmdtxtredir(n, ">|", 1); 1433 break; 1434 case NFROM: 1435 cmdtxtredir(n, "<", 0); 1436 break; 1437 case NFROMTO: 1438 cmdtxtredir(n, "<>", 0); 1439 break; 1440 case NFROMFD: 1441 cmdtxtredir(n, "<&", 0); 1442 break; 1443 case NHERE: 1444 case NXHERE: 1445 cmdputs("<<..."); 1446 break; 1447 default: 1448 cmdputs("???"); 1449 break; 1450 } 1451 } 1452 1453 1454 1455 static void 1456 cmdputs(const char *s) 1457 { 1458 const char *p; 1459 char *q; 1460 char c; 1461 int subtype = 0; 1462 1463 if (cmdnleft <= 0) 1464 return; 1465 p = s; 1466 q = cmdnextc; 1467 while ((c = *p++) != '\0') { 1468 if (c == CTLESC) 1469 *q++ = *p++; 1470 else if (c == CTLVAR) { 1471 *q++ = '$'; 1472 if (--cmdnleft > 0) 1473 *q++ = '{'; 1474 subtype = *p++; 1475 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0) 1476 *q++ = '#'; 1477 } else if (c == '=' && subtype != 0) { 1478 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL]; 1479 if (*q) 1480 q++; 1481 else 1482 cmdnleft++; 1483 if (((subtype & VSTYPE) == VSTRIMLEFTMAX || 1484 (subtype & VSTYPE) == VSTRIMRIGHTMAX) && 1485 --cmdnleft > 0) 1486 *q = q[-1], q++; 1487 subtype = 0; 1488 } else if (c == CTLENDVAR) { 1489 *q++ = '}'; 1490 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) { 1491 cmdnleft -= 5; 1492 if (cmdnleft > 0) { 1493 *q++ = '$'; 1494 *q++ = '('; 1495 *q++ = '.'; 1496 *q++ = '.'; 1497 *q++ = '.'; 1498 *q++ = ')'; 1499 } 1500 } else if (c == CTLARI) { 1501 cmdnleft -= 2; 1502 if (cmdnleft > 0) { 1503 *q++ = '$'; 1504 *q++ = '('; 1505 *q++ = '('; 1506 } 1507 p++; 1508 } else if (c == CTLENDARI) { 1509 if (--cmdnleft > 0) { 1510 *q++ = ')'; 1511 *q++ = ')'; 1512 } 1513 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND) 1514 cmdnleft++; /* ignore */ 1515 else 1516 *q++ = c; 1517 if (--cmdnleft <= 0) { 1518 *q++ = '.'; 1519 *q++ = '.'; 1520 *q++ = '.'; 1521 break; 1522 } 1523 } 1524 cmdnextc = q; 1525 } 1526