1 /* $NetBSD: jobs.c,v 1.62 2003/12/18 00:56:05 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Kenneth Almquist. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95"; 39 #else 40 __RCSID("$NetBSD: jobs.c,v 1.62 2003/12/18 00:56:05 christos Exp $"); 41 #endif 42 #endif /* not lint */ 43 44 #include <fcntl.h> 45 #include <signal.h> 46 #include <errno.h> 47 #include <unistd.h> 48 #include <stdlib.h> 49 #include <paths.h> 50 #include <sys/types.h> 51 #include <sys/param.h> 52 #ifdef BSD 53 #include <sys/wait.h> 54 #include <sys/time.h> 55 #include <sys/resource.h> 56 #endif 57 #include <sys/ioctl.h> 58 59 #include "shell.h" 60 #if JOBS 61 #if OLD_TTY_DRIVER 62 #include "sgtty.h" 63 #else 64 #include <termios.h> 65 #endif 66 #undef CEOF /* syntax.h redefines this */ 67 #endif 68 #include "redir.h" 69 #include "show.h" 70 #include "main.h" 71 #include "parser.h" 72 #include "nodes.h" 73 #include "jobs.h" 74 #include "options.h" 75 #include "trap.h" 76 #include "syntax.h" 77 #include "input.h" 78 #include "output.h" 79 #include "memalloc.h" 80 #include "error.h" 81 #include "mystring.h" 82 83 84 static struct job *jobtab; /* array of jobs */ 85 static int njobs; /* size of array */ 86 static int jobs_invalid; /* set in child */ 87 MKINIT pid_t backgndpid = -1; /* pid of last background process */ 88 #if JOBS 89 int initialpgrp; /* pgrp of shell on invocation */ 90 static int curjob = -1; /* current job */ 91 #endif 92 static int ttyfd = -1; 93 94 STATIC void restartjob(struct job *); 95 STATIC void freejob(struct job *); 96 STATIC struct job *getjob(const char *, int); 97 STATIC int dowait(int, struct job *); 98 STATIC int onsigchild(void); 99 STATIC int waitproc(int, struct job *, int *); 100 STATIC void cmdtxt(union node *); 101 STATIC void cmdlist(union node *, int); 102 STATIC void cmdputs(const char *); 103 104 #ifdef OLD_TTY_DRIVER 105 static pid_t tcgetpgrp(int fd); 106 static int tcsetpgrp(int fd, pid_t pgrp); 107 108 static pid_t 109 tcgetpgrp(int fd) 110 { 111 pid_t pgrp; 112 if (ioctl(fd, TIOCGPGRP, (char *)&pgrp) == -1) 113 return -1; 114 else 115 return pgrp; 116 } 117 118 static int 119 tcsetpgrp(int fd, pid_tpgrp) 120 { 121 return ioctl(fd, TIOCSPGRP, (char *)&pgrp); 122 } 123 #endif 124 125 /* 126 * Turn job control on and off. 127 * 128 * Note: This code assumes that the third arg to ioctl is a character 129 * pointer, which is true on Berkeley systems but not System V. Since 130 * System V doesn't have job control yet, this isn't a problem now. 131 */ 132 133 MKINIT int jobctl; 134 135 void 136 setjobctl(int on) 137 { 138 #ifdef OLD_TTY_DRIVER 139 int ldisc; 140 #endif 141 142 if (on == jobctl || rootshell == 0) 143 return; 144 if (on) { 145 #if defined(FIOCLEX) || defined(FD_CLOEXEC) 146 int err; 147 int i; 148 if (ttyfd != -1) 149 close(ttyfd); 150 if ((ttyfd = open("/dev/tty", O_RDWR)) == -1) { 151 for (i = 0; i < 3; i++) { 152 if (isatty(i) && (ttyfd = dup(i)) != -1) 153 break; 154 } 155 if (i == 3) 156 goto out; 157 } 158 /* Move to a high fd */ 159 for (i = 10; i > 2; i--) { 160 if ((err = fcntl(ttyfd, F_DUPFD, (1 << i) - 1)) != -1) 161 break; 162 } 163 if (err != -1) { 164 close(ttyfd); 165 ttyfd = err; 166 } 167 #ifdef FIOCLEX 168 err = ioctl(ttyfd, FIOCLEX, 0); 169 #elif FD_CLOEXEC 170 err = fcntl(ttyfd, F_SETFD, 171 fcntl(ttyfd, F_GETFD, 0) | FD_CLOEXEC); 172 #endif 173 if (err == -1) { 174 close(ttyfd); 175 ttyfd = -1; 176 goto out; 177 } 178 #else 179 out2str("sh: Need FIOCLEX or FD_CLOEXEC to support job control"); 180 goto out; 181 #endif 182 do { /* while we are in the background */ 183 if ((initialpgrp = tcgetpgrp(ttyfd)) < 0) { 184 out: 185 out2str("sh: can't access tty; job control turned off\n"); 186 mflag = 0; 187 return; 188 } 189 if (initialpgrp == -1) 190 initialpgrp = getpgrp(); 191 else if (initialpgrp != getpgrp()) { 192 killpg(0, SIGTTIN); 193 continue; 194 } 195 } while (0); 196 197 #ifdef OLD_TTY_DRIVER 198 if (ioctl(ttyfd, TIOCGETD, (char *)&ldisc) < 0 199 || ldisc != NTTYDISC) { 200 out2str("sh: need new tty driver to run job control; job control turned off\n"); 201 mflag = 0; 202 return; 203 } 204 #endif 205 setsignal(SIGTSTP, 0); 206 setsignal(SIGTTOU, 0); 207 setsignal(SIGTTIN, 0); 208 if (getpgid(0) != rootpid && setpgid(0, rootpid) == -1) 209 error("Cannot set process group (%s) at %d", 210 strerror(errno), __LINE__); 211 if (tcsetpgrp(ttyfd, rootpid) == -1) 212 error("Cannot set tty process group (%s) at %d", 213 strerror(errno), __LINE__); 214 } else { /* turning job control off */ 215 if (getpgid(0) != initialpgrp && setpgid(0, initialpgrp) == -1) 216 error("Cannot set process group (%s) at %d", 217 strerror(errno), __LINE__); 218 if (tcsetpgrp(ttyfd, initialpgrp) == -1) 219 error("Cannot set tty process group (%s) at %d", 220 strerror(errno), __LINE__); 221 close(ttyfd); 222 ttyfd = -1; 223 setsignal(SIGTSTP, 0); 224 setsignal(SIGTTOU, 0); 225 setsignal(SIGTTIN, 0); 226 } 227 jobctl = on; 228 } 229 230 231 #ifdef mkinit 232 INCLUDE <stdlib.h> 233 234 SHELLPROC { 235 backgndpid = -1; 236 #if JOBS 237 jobctl = 0; 238 #endif 239 } 240 241 #endif 242 243 244 245 #if JOBS 246 int 247 fgcmd(int argc, char **argv) 248 { 249 struct job *jp; 250 int i; 251 int status; 252 253 nextopt(""); 254 jp = getjob(*argptr, 0); 255 if (jp->jobctl == 0) 256 error("job not created under job control"); 257 out1fmt("%s", jp->ps[0].cmd); 258 for (i = 1; i < jp->nprocs; i++) 259 out1fmt(" | %s", jp->ps[i].cmd ); 260 out1c('\n'); 261 flushall(); 262 263 for (i = 0; i < jp->nprocs; i++) 264 if (tcsetpgrp(ttyfd, jp->ps[i].pid) != -1) 265 break; 266 267 if (i >= jp->nprocs) { 268 error("Cannot set tty process group (%s) at %d", 269 strerror(errno), __LINE__); 270 } 271 restartjob(jp); 272 INTOFF; 273 status = waitforjob(jp); 274 INTON; 275 return status; 276 } 277 278 static void 279 set_curjob(struct job *jp, int mode) 280 { 281 struct job *jp1, *jp2; 282 int i, ji; 283 284 ji = jp - jobtab; 285 286 /* first remove from list */ 287 if (ji == curjob) 288 curjob = jp->prev_job; 289 else { 290 for (i = 0; i < njobs; i++) { 291 if (jobtab[i].prev_job != ji) 292 continue; 293 jobtab[i].prev_job = jp->prev_job; 294 break; 295 } 296 } 297 298 /* Then re-insert in correct position */ 299 switch (mode) { 300 case 0: /* job being deleted */ 301 jp->prev_job = -1; 302 break; 303 case 1: /* newly created job or backgrounded job, 304 put after all stopped jobs. */ 305 if (curjob != -1 && jobtab[curjob].state == JOBSTOPPED) { 306 for (jp1 = jobtab + curjob; ; jp1 = jp2) { 307 if (jp1->prev_job == -1) 308 break; 309 jp2 = jobtab + jp1->prev_job; 310 if (jp2->state != JOBSTOPPED) 311 break; 312 } 313 jp->prev_job = jp1->prev_job; 314 jp1->prev_job = ji; 315 break; 316 } 317 /* FALLTHROUGH */ 318 case 2: /* newly stopped job - becomes curjob */ 319 jp->prev_job = curjob; 320 curjob = ji; 321 break; 322 } 323 } 324 325 int 326 bgcmd(int argc, char **argv) 327 { 328 struct job *jp; 329 int i; 330 331 nextopt(""); 332 do { 333 jp = getjob(*argptr, 0); 334 if (jp->jobctl == 0) 335 error("job not created under job control"); 336 set_curjob(jp, 1); 337 out1fmt("[%ld] %s", (long)(jp - jobtab + 1), jp->ps[0].cmd); 338 for (i = 1; i < jp->nprocs; i++) 339 out1fmt(" | %s", jp->ps[i].cmd ); 340 out1c('\n'); 341 flushall(); 342 restartjob(jp); 343 } while (*argptr && *++argptr); 344 return 0; 345 } 346 347 348 STATIC void 349 restartjob(struct job *jp) 350 { 351 struct procstat *ps; 352 int i; 353 354 if (jp->state == JOBDONE) 355 return; 356 INTOFF; 357 for (i = 0; i < jp->nprocs; i++) 358 if (killpg(jp->ps[i].pid, SIGCONT) != -1) 359 break; 360 if (i >= jp->nprocs) 361 error("Cannot continue job (%s)", strerror(errno)); 362 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) { 363 if (WIFSTOPPED(ps->status)) { 364 ps->status = -1; 365 jp->state = JOBRUNNING; 366 } 367 } 368 INTON; 369 } 370 #endif 371 372 static void 373 showjob(struct output *out, struct job *jp, int mode) 374 { 375 int procno; 376 int st; 377 struct procstat *ps; 378 int col; 379 char s[64]; 380 381 #if JOBS 382 if (mode & SHOW_PGID) { 383 /* just output process (group) id of pipeline */ 384 outfmt(out, "%ld\n", (long)jp->ps->pid); 385 return; 386 } 387 #endif 388 389 procno = jp->nprocs; 390 if (!procno) 391 return; 392 393 if (mode & SHOW_PID) 394 mode |= SHOW_MULTILINE; 395 396 if ((procno > 1 && !(mode & SHOW_MULTILINE)) 397 || (mode & SHOW_SIGNALLED)) { 398 /* See if we have more than one status to report */ 399 ps = jp->ps; 400 st = ps->status; 401 do { 402 int st1 = ps->status; 403 if (st1 != st) 404 /* yes - need multi-line output */ 405 mode |= SHOW_MULTILINE; 406 if (st1 == -1 || !(mode & SHOW_SIGNALLED) || WIFEXITED(st1)) 407 continue; 408 if (WIFSTOPPED(st1) || ((st1 = WTERMSIG(st1) & 0x7f) 409 && st1 != SIGINT && st1 != SIGPIPE)) 410 mode |= SHOW_ISSIG; 411 412 } while (ps++, --procno); 413 procno = jp->nprocs; 414 } 415 416 if (mode & SHOW_SIGNALLED && !(mode & SHOW_ISSIG)) { 417 if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE)) { 418 TRACE(("showjob: freeing job %d\n", jp - jobtab + 1)); 419 freejob(jp); 420 } 421 return; 422 } 423 424 for (ps = jp->ps; --procno >= 0; ps++) { /* for each process */ 425 if (ps == jp->ps) 426 fmtstr(s, 16, "[%ld] %c ", 427 (long)(jp - jobtab + 1), 428 #if JOBS 429 jp == jobtab + curjob ? '+' : 430 curjob != -1 && jp == jobtab + 431 jobtab[curjob].prev_job ? '-' : 432 #endif 433 ' '); 434 else 435 fmtstr(s, 16, " " ); 436 col = strlen(s); 437 if (mode & SHOW_PID) { 438 fmtstr(s + col, 16, "%ld ", (long)ps->pid); 439 col += strlen(s + col); 440 } 441 if (ps->status == -1) { 442 scopy("Running", s + col); 443 } else if (WIFEXITED(ps->status)) { 444 st = WEXITSTATUS(ps->status); 445 if (st) 446 fmtstr(s + col, 16, "Done(%d)", st); 447 else 448 fmtstr(s + col, 16, "Done"); 449 } else { 450 #if JOBS 451 if (WIFSTOPPED(ps->status)) 452 st = WSTOPSIG(ps->status); 453 else /* WIFSIGNALED(ps->status) */ 454 #endif 455 st = WTERMSIG(ps->status); 456 st &= 0x7f; 457 if (st < NSIG && sys_siglist[st]) 458 scopyn(sys_siglist[st], s + col, 32); 459 else 460 fmtstr(s + col, 16, "Signal %d", st); 461 if (WCOREDUMP(ps->status)) { 462 col += strlen(s + col); 463 scopyn(" (core dumped)", s + col, 64 - col); 464 } 465 } 466 col += strlen(s + col); 467 outstr(s, out); 468 do { 469 outc(' ', out); 470 col++; 471 } while (col < 30); 472 outstr(ps->cmd, out); 473 if (mode & SHOW_MULTILINE) { 474 if (procno > 0) { 475 outc(' ', out); 476 outc('|', out); 477 } 478 } else { 479 while (--procno >= 0) 480 outfmt(out, " | %s", (++ps)->cmd ); 481 } 482 outc('\n', out); 483 } 484 flushout(out); 485 jp->changed = 0; 486 if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE)) 487 freejob(jp); 488 } 489 490 491 int 492 jobscmd(int argc, char **argv) 493 { 494 int mode, m; 495 int sv = jobs_invalid; 496 497 jobs_invalid = 0; 498 mode = 0; 499 while ((m = nextopt("lp"))) 500 if (m == 'l') 501 mode = SHOW_PID; 502 else 503 mode = SHOW_PGID; 504 if (*argptr) 505 do 506 showjob(out1, getjob(*argptr,0), mode); 507 while (*++argptr); 508 else 509 showjobs(out1, mode); 510 jobs_invalid = sv; 511 return 0; 512 } 513 514 515 /* 516 * Print a list of jobs. If "change" is nonzero, only print jobs whose 517 * statuses have changed since the last call to showjobs. 518 * 519 * If the shell is interrupted in the process of creating a job, the 520 * result may be a job structure containing zero processes. Such structures 521 * will be freed here. 522 */ 523 524 void 525 showjobs(struct output *out, int mode) 526 { 527 int jobno; 528 struct job *jp; 529 int silent = 0, gotpid; 530 531 TRACE(("showjobs(%x) called\n", mode)); 532 533 /* If not even one one job changed, there is nothing to do */ 534 gotpid = dowait(0, NULL); 535 while (dowait(0, NULL) > 0) 536 continue; 537 #ifdef JOBS 538 /* 539 * Check if we are not in our foreground group, and if not 540 * put us in it. 541 */ 542 if (mflag && gotpid != -1 && tcgetpgrp(ttyfd) != getpid()) { 543 if (tcsetpgrp(ttyfd, getpid()) == -1) 544 error("Cannot set tty process group (%s) at %d", 545 strerror(errno), __LINE__); 546 TRACE(("repaired tty process group\n")); 547 silent = 1; 548 } 549 #endif 550 if (jobs_invalid) 551 return; 552 553 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) { 554 if (!jp->used) 555 continue; 556 if (jp->nprocs == 0) { 557 freejob(jp); 558 continue; 559 } 560 if ((mode & SHOW_CHANGED) && !jp->changed) 561 continue; 562 if (silent && jp->changed) { 563 jp->changed = 0; 564 continue; 565 } 566 showjob(out, jp, mode); 567 } 568 } 569 570 /* 571 * Mark a job structure as unused. 572 */ 573 574 STATIC void 575 freejob(struct job *jp) 576 { 577 INTOFF; 578 if (jp->ps != &jp->ps0) { 579 ckfree(jp->ps); 580 jp->ps = &jp->ps0; 581 } 582 jp->nprocs = 0; 583 jp->used = 0; 584 #if JOBS 585 set_curjob(jp, 0); 586 #endif 587 INTON; 588 } 589 590 591 592 int 593 waitcmd(int argc, char **argv) 594 { 595 struct job *job; 596 int status, retval; 597 struct job *jp; 598 599 nextopt(""); 600 601 if (!*argptr) { 602 /* wait for all jobs */ 603 jp = jobtab; 604 if (jobs_invalid) 605 return 0; 606 for (;;) { 607 if (jp >= jobtab + njobs) { 608 /* no running procs */ 609 return 0; 610 } 611 if (!jp->used || jp->state != JOBRUNNING) { 612 jp++; 613 continue; 614 } 615 if (dowait(1, (struct job *)NULL) == -1) 616 return 128 + SIGINT; 617 jp = jobtab; 618 } 619 } 620 621 for (; *argptr; argptr++) { 622 job = getjob(*argptr, 1); 623 if (!job) { 624 retval = 127; 625 continue; 626 } 627 /* loop until process terminated or stopped */ 628 while (job->state == JOBRUNNING) { 629 if (dowait(1, (struct job *)NULL) == -1) 630 return 128 + SIGINT; 631 } 632 status = job->ps[job->nprocs].status; 633 if (WIFEXITED(status)) 634 retval = WEXITSTATUS(status); 635 #if JOBS 636 else if (WIFSTOPPED(status)) 637 retval = WSTOPSIG(status) + 128; 638 #endif 639 else { 640 /* XXX: limits number of signals */ 641 retval = WTERMSIG(status) + 128; 642 } 643 if (!iflag) 644 freejob(job); 645 } 646 return retval; 647 } 648 649 650 651 int 652 jobidcmd(int argc, char **argv) 653 { 654 struct job *jp; 655 int i; 656 657 nextopt(""); 658 jp = getjob(*argptr, 0); 659 for (i = 0 ; i < jp->nprocs ; ) { 660 out1fmt("%ld", (long)jp->ps[i].pid); 661 out1c(++i < jp->nprocs ? ' ' : '\n'); 662 } 663 return 0; 664 } 665 666 int 667 getjobpgrp(const char *name) 668 { 669 struct job *jp; 670 671 jp = getjob(name, 1); 672 if (jp == 0) 673 return 0; 674 return -jp->ps[0].pid; 675 } 676 677 /* 678 * Convert a job name to a job structure. 679 */ 680 681 STATIC struct job * 682 getjob(const char *name, int noerror) 683 { 684 int jobno = -1; 685 struct job *jp; 686 int pid; 687 int i; 688 const char *err_msg = "No such job: %s"; 689 690 if (name == NULL) { 691 #if JOBS 692 jobno = curjob; 693 #endif 694 err_msg = "No current job"; 695 } else if (name[0] == '%') { 696 if (is_number(name + 1)) { 697 jobno = number(name + 1) - 1; 698 } else if (!name[2]) { 699 switch (name[1]) { 700 #if JOBS 701 case 0: 702 case '+': 703 case '%': 704 jobno = curjob; 705 err_msg = "No current job"; 706 break; 707 case '-': 708 jobno = curjob; 709 if (jobno != -1) 710 jobno = jobtab[jobno].prev_job; 711 err_msg = "No previous job"; 712 break; 713 #endif 714 default: 715 goto check_pattern; 716 } 717 } else { 718 struct job *found; 719 check_pattern: 720 found = NULL; 721 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 722 if (!jp->used || jp->nprocs <= 0) 723 continue; 724 if ((name[1] == '?' 725 && strstr(jp->ps[0].cmd, name + 2)) 726 || prefix(name + 1, jp->ps[0].cmd)) { 727 if (found) { 728 err_msg = "%s: ambiguous"; 729 found = 0; 730 break; 731 } 732 found = jp; 733 } 734 } 735 if (found) 736 return found; 737 } 738 739 } else if (is_number(name)) { 740 pid = number(name); 741 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) { 742 if (jp->used && jp->nprocs > 0 743 && jp->ps[jp->nprocs - 1].pid == pid) 744 return jp; 745 } 746 } 747 748 if (!jobs_invalid && jobno >= 0 && jobno < njobs) { 749 jp = jobtab + jobno; 750 if (jp->used) 751 return jp; 752 } 753 if (!noerror) 754 error(err_msg, name); 755 return 0; 756 } 757 758 759 760 /* 761 * Return a new job structure, 762 */ 763 764 struct job * 765 makejob(union node *node, int nprocs) 766 { 767 int i; 768 struct job *jp; 769 770 if (jobs_invalid) { 771 for (i = njobs, jp = jobtab ; --i >= 0 ; jp++) { 772 if (jp->used) 773 freejob(jp); 774 } 775 jobs_invalid = 0; 776 } 777 778 for (i = njobs, jp = jobtab ; ; jp++) { 779 if (--i < 0) { 780 INTOFF; 781 if (njobs == 0) { 782 jobtab = ckmalloc(4 * sizeof jobtab[0]); 783 } else { 784 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]); 785 memcpy(jp, jobtab, njobs * sizeof jp[0]); 786 /* Relocate `ps' pointers */ 787 for (i = 0; i < njobs; i++) 788 if (jp[i].ps == &jobtab[i].ps0) 789 jp[i].ps = &jp[i].ps0; 790 ckfree(jobtab); 791 jobtab = jp; 792 } 793 jp = jobtab + njobs; 794 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0); 795 INTON; 796 break; 797 } 798 if (jp->used == 0) 799 break; 800 } 801 INTOFF; 802 jp->state = JOBRUNNING; 803 jp->used = 1; 804 jp->changed = 0; 805 jp->nprocs = 0; 806 #if JOBS 807 jp->jobctl = jobctl; 808 set_curjob(jp, 1); 809 #endif 810 if (nprocs > 1) { 811 jp->ps = ckmalloc(nprocs * sizeof (struct procstat)); 812 } else { 813 jp->ps = &jp->ps0; 814 } 815 INTON; 816 TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs, 817 jp - jobtab + 1)); 818 return jp; 819 } 820 821 822 /* 823 * Fork off a subshell. If we are doing job control, give the subshell its 824 * own process group. Jp is a job structure that the job is to be added to. 825 * N is the command that will be evaluated by the child. Both jp and n may 826 * be NULL. The mode parameter can be one of the following: 827 * FORK_FG - Fork off a foreground process. 828 * FORK_BG - Fork off a background process. 829 * FORK_NOJOB - Like FORK_FG, but don't give the process its own 830 * process group even if job control is on. 831 * 832 * When job control is turned off, background processes have their standard 833 * input redirected to /dev/null (except for the second and later processes 834 * in a pipeline). 835 */ 836 837 int 838 forkshell(struct job *jp, union node *n, int mode) 839 { 840 int pid; 841 842 TRACE(("forkshell(%%%d, %p, %d) called\n", jp - jobtab, n, mode)); 843 switch ((pid = fork())) { 844 case -1: 845 TRACE(("Fork failed, errno=%d\n", errno)); 846 INTON; 847 error("Cannot fork"); 848 break; 849 case 0: 850 forkchild(jp, n, mode, 0); 851 return 0; 852 default: 853 return forkparent(jp, n, mode, pid); 854 } 855 } 856 857 int 858 forkparent(struct job *jp, union node *n, int mode, pid_t pid) 859 { 860 int pgrp; 861 862 if (rootshell && mode != FORK_NOJOB && mflag) { 863 if (jp == NULL || jp->nprocs == 0) 864 pgrp = pid; 865 else 866 pgrp = jp->ps[0].pid; 867 /* This can fail because we are doing it in the child also */ 868 (void)setpgid(pid, pgrp); 869 } 870 if (mode == FORK_BG) 871 backgndpid = pid; /* set $! */ 872 if (jp) { 873 struct procstat *ps = &jp->ps[jp->nprocs++]; 874 ps->pid = pid; 875 ps->status = -1; 876 ps->cmd[0] = 0; 877 if (/* iflag && rootshell && */ n) 878 commandtext(ps, n); 879 } 880 TRACE(("In parent shell: child = %d\n", pid)); 881 return pid; 882 } 883 884 void 885 forkchild(struct job *jp, union node *n, int mode, int vforked) 886 { 887 int wasroot; 888 int pgrp; 889 const char *devnull = _PATH_DEVNULL; 890 const char *nullerr = "Can't open %s"; 891 892 wasroot = rootshell; 893 TRACE(("Child shell %d\n", getpid())); 894 if (!vforked) 895 rootshell = 0; 896 897 closescript(vforked); 898 clear_traps(vforked); 899 #if JOBS 900 if (!vforked) 901 jobctl = 0; /* do job control only in root shell */ 902 if (wasroot && mode != FORK_NOJOB && mflag) { 903 if (jp == NULL || jp->nprocs == 0) 904 pgrp = getpid(); 905 else 906 pgrp = jp->ps[0].pid; 907 /* This can fail because we are doing it in the parent also */ 908 (void)setpgid(0, pgrp); 909 if (mode == FORK_FG) { 910 if (tcsetpgrp(ttyfd, pgrp) == -1) 911 error("Cannot set tty process group (%s) at %d", 912 strerror(errno), __LINE__); 913 } 914 setsignal(SIGTSTP, vforked); 915 setsignal(SIGTTOU, vforked); 916 } else if (mode == FORK_BG) { 917 ignoresig(SIGINT, vforked); 918 ignoresig(SIGQUIT, vforked); 919 if ((jp == NULL || jp->nprocs == 0) && 920 ! fd0_redirected_p ()) { 921 close(0); 922 if (open(devnull, O_RDONLY) != 0) 923 error(nullerr, devnull); 924 } 925 } 926 #else 927 if (mode == FORK_BG) { 928 ignoresig(SIGINT, vforked); 929 ignoresig(SIGQUIT, vforked); 930 if ((jp == NULL || jp->nprocs == 0) && 931 ! fd0_redirected_p ()) { 932 close(0); 933 if (open(devnull, O_RDONLY) != 0) 934 error(nullerr, devnull); 935 } 936 } 937 #endif 938 if (wasroot && iflag) { 939 setsignal(SIGINT, vforked); 940 setsignal(SIGQUIT, vforked); 941 setsignal(SIGTERM, vforked); 942 } 943 944 if (!vforked) 945 jobs_invalid = 1; 946 } 947 948 /* 949 * Wait for job to finish. 950 * 951 * Under job control we have the problem that while a child process is 952 * running interrupts generated by the user are sent to the child but not 953 * to the shell. This means that an infinite loop started by an inter- 954 * active user may be hard to kill. With job control turned off, an 955 * interactive user may place an interactive program inside a loop. If 956 * the interactive program catches interrupts, the user doesn't want 957 * these interrupts to also abort the loop. The approach we take here 958 * is to have the shell ignore interrupt signals while waiting for a 959 * forground process to terminate, and then send itself an interrupt 960 * signal if the child process was terminated by an interrupt signal. 961 * Unfortunately, some programs want to do a bit of cleanup and then 962 * exit on interrupt; unless these processes terminate themselves by 963 * sending a signal to themselves (instead of calling exit) they will 964 * confuse this approach. 965 */ 966 967 int 968 waitforjob(struct job *jp) 969 { 970 #if JOBS 971 int mypgrp = getpgrp(); 972 #endif 973 int status; 974 int st; 975 976 INTOFF; 977 TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1)); 978 while (jp->state == JOBRUNNING) { 979 dowait(1, jp); 980 } 981 #if JOBS 982 if (jp->jobctl) { 983 if (tcsetpgrp(ttyfd, mypgrp) == -1) 984 error("Cannot set tty process group (%s) at %d", 985 strerror(errno), __LINE__); 986 } 987 if (jp->state == JOBSTOPPED && curjob != jp - jobtab) 988 set_curjob(jp, 2); 989 #endif 990 status = jp->ps[jp->nprocs - 1].status; 991 /* convert to 8 bits */ 992 if (WIFEXITED(status)) 993 st = WEXITSTATUS(status); 994 #if JOBS 995 else if (WIFSTOPPED(status)) 996 st = WSTOPSIG(status) + 128; 997 #endif 998 else 999 st = WTERMSIG(status) + 128; 1000 TRACE(("waitforjob: job %d, nproc %d, status %x, st %x\n", 1001 jp - jobtab + 1, jp->nprocs, status, st )); 1002 #if JOBS 1003 if (jp->jobctl) { 1004 /* 1005 * This is truly gross. 1006 * If we're doing job control, then we did a TIOCSPGRP which 1007 * caused us (the shell) to no longer be in the controlling 1008 * session -- so we wouldn't have seen any ^C/SIGINT. So, we 1009 * intuit from the subprocess exit status whether a SIGINT 1010 * occurred, and if so interrupt ourselves. Yuck. - mycroft 1011 */ 1012 if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT) 1013 raise(SIGINT); 1014 } 1015 #endif 1016 if (! JOBS || jp->state == JOBDONE) 1017 freejob(jp); 1018 INTON; 1019 return st; 1020 } 1021 1022 1023 1024 /* 1025 * Wait for a process to terminate. 1026 */ 1027 1028 STATIC int 1029 dowait(int block, struct job *job) 1030 { 1031 int pid; 1032 int status; 1033 struct procstat *sp; 1034 struct job *jp; 1035 struct job *thisjob; 1036 int done; 1037 int stopped; 1038 extern volatile char gotsig[]; 1039 1040 TRACE(("dowait(%d) called\n", block)); 1041 do { 1042 pid = waitproc(block, job, &status); 1043 TRACE(("wait returns pid %d, status %d\n", pid, status)); 1044 } while (pid == -1 && errno == EINTR && gotsig[SIGINT - 1] == 0); 1045 if (pid <= 0) 1046 return pid; 1047 INTOFF; 1048 thisjob = NULL; 1049 for (jp = jobtab ; jp < jobtab + njobs ; jp++) { 1050 if (jp->used) { 1051 done = 1; 1052 stopped = 1; 1053 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) { 1054 if (sp->pid == -1) 1055 continue; 1056 if (sp->pid == pid) { 1057 TRACE(("Job %d: changing status of proc %d from 0x%x to 0x%x\n", jp - jobtab + 1, pid, sp->status, status)); 1058 sp->status = status; 1059 thisjob = jp; 1060 } 1061 if (sp->status == -1) 1062 stopped = 0; 1063 else if (WIFSTOPPED(sp->status)) 1064 done = 0; 1065 } 1066 if (stopped) { /* stopped or done */ 1067 int state = done ? JOBDONE : JOBSTOPPED; 1068 if (jp->state != state) { 1069 TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state)); 1070 jp->state = state; 1071 #if JOBS 1072 if (done) 1073 set_curjob(jp, 0); 1074 #endif 1075 } 1076 } 1077 } 1078 } 1079 1080 if (thisjob && thisjob->state != JOBRUNNING) { 1081 int mode = 0; 1082 if (!rootshell || !iflag) 1083 mode = SHOW_SIGNALLED; 1084 if (job == thisjob) 1085 mode = SHOW_SIGNALLED | SHOW_NO_FREE; 1086 if (mode) 1087 showjob(out2, thisjob, mode); 1088 else { 1089 TRACE(("Not printing status, rootshell=%d, job=%p\n", 1090 rootshell, job)); 1091 thisjob->changed = 1; 1092 } 1093 } 1094 1095 INTON; 1096 return pid; 1097 } 1098 1099 1100 1101 /* 1102 * Do a wait system call. If job control is compiled in, we accept 1103 * stopped processes. If block is zero, we return a value of zero 1104 * rather than blocking. 1105 * 1106 * System V doesn't have a non-blocking wait system call. It does 1107 * have a SIGCLD signal that is sent to a process when one of it's 1108 * children dies. The obvious way to use SIGCLD would be to install 1109 * a handler for SIGCLD which simply bumped a counter when a SIGCLD 1110 * was received, and have waitproc bump another counter when it got 1111 * the status of a process. Waitproc would then know that a wait 1112 * system call would not block if the two counters were different. 1113 * This approach doesn't work because if a process has children that 1114 * have not been waited for, System V will send it a SIGCLD when it 1115 * installs a signal handler for SIGCLD. What this means is that when 1116 * a child exits, the shell will be sent SIGCLD signals continuously 1117 * until is runs out of stack space, unless it does a wait call before 1118 * restoring the signal handler. The code below takes advantage of 1119 * this (mis)feature by installing a signal handler for SIGCLD and 1120 * then checking to see whether it was called. If there are any 1121 * children to be waited for, it will be. 1122 * 1123 * If neither SYSV nor BSD is defined, we don't implement nonblocking 1124 * waits at all. In this case, the user will not be informed when 1125 * a background process until the next time she runs a real program 1126 * (as opposed to running a builtin command or just typing return), 1127 * and the jobs command may give out of date information. 1128 */ 1129 1130 #ifdef SYSV 1131 STATIC int gotsigchild; 1132 1133 STATIC int onsigchild() { 1134 gotsigchild = 1; 1135 } 1136 #endif 1137 1138 1139 STATIC int 1140 waitproc(int block, struct job *jp, int *status) 1141 { 1142 #ifdef BSD 1143 int flags = 0; 1144 1145 #if JOBS 1146 if (jp != NULL && jp->jobctl) 1147 flags |= WUNTRACED; 1148 #endif 1149 if (block == 0) 1150 flags |= WNOHANG; 1151 return wait3(status, flags, (struct rusage *)NULL); 1152 #else 1153 #ifdef SYSV 1154 int (*save)(); 1155 1156 if (block == 0) { 1157 gotsigchild = 0; 1158 save = signal(SIGCLD, onsigchild); 1159 signal(SIGCLD, save); 1160 if (gotsigchild == 0) 1161 return 0; 1162 } 1163 return wait(status); 1164 #else 1165 if (block == 0) 1166 return 0; 1167 return wait(status); 1168 #endif 1169 #endif 1170 } 1171 1172 /* 1173 * return 1 if there are stopped jobs, otherwise 0 1174 */ 1175 int job_warning = 0; 1176 int 1177 stoppedjobs(void) 1178 { 1179 int jobno; 1180 struct job *jp; 1181 1182 if (job_warning || jobs_invalid) 1183 return (0); 1184 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) { 1185 if (jp->used == 0) 1186 continue; 1187 if (jp->state == JOBSTOPPED) { 1188 out2str("You have stopped jobs.\n"); 1189 job_warning = 2; 1190 return (1); 1191 } 1192 } 1193 1194 return (0); 1195 } 1196 1197 /* 1198 * Return a string identifying a command (to be printed by the 1199 * jobs command). 1200 */ 1201 1202 STATIC char *cmdnextc; 1203 STATIC int cmdnleft; 1204 1205 void 1206 commandtext(struct procstat *ps, union node *n) 1207 { 1208 int len; 1209 1210 cmdnextc = ps->cmd; 1211 if (iflag || mflag || sizeof ps->cmd < 100) 1212 len = sizeof(ps->cmd); 1213 else 1214 len = sizeof(ps->cmd) / 10; 1215 cmdnleft = len; 1216 cmdtxt(n); 1217 if (cmdnleft <= 0) { 1218 char *p = ps->cmd + len - 4; 1219 p[0] = '.'; 1220 p[1] = '.'; 1221 p[2] = '.'; 1222 p[3] = 0; 1223 } else 1224 *cmdnextc = '\0'; 1225 TRACE(("commandtext: ps->cmd %x, end %x, left %d\n\t\"%s\"\n", 1226 ps->cmd, cmdnextc, cmdnleft, ps->cmd)); 1227 } 1228 1229 1230 STATIC void 1231 cmdtxt(union node *n) 1232 { 1233 union node *np; 1234 struct nodelist *lp; 1235 const char *p; 1236 int i; 1237 char s[2]; 1238 1239 if (n == NULL || cmdnleft <= 0) 1240 return; 1241 switch (n->type) { 1242 case NSEMI: 1243 cmdtxt(n->nbinary.ch1); 1244 cmdputs("; "); 1245 cmdtxt(n->nbinary.ch2); 1246 break; 1247 case NAND: 1248 cmdtxt(n->nbinary.ch1); 1249 cmdputs(" && "); 1250 cmdtxt(n->nbinary.ch2); 1251 break; 1252 case NOR: 1253 cmdtxt(n->nbinary.ch1); 1254 cmdputs(" || "); 1255 cmdtxt(n->nbinary.ch2); 1256 break; 1257 case NPIPE: 1258 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) { 1259 cmdtxt(lp->n); 1260 if (lp->next) 1261 cmdputs(" | "); 1262 } 1263 break; 1264 case NSUBSHELL: 1265 cmdputs("("); 1266 cmdtxt(n->nredir.n); 1267 cmdputs(")"); 1268 break; 1269 case NREDIR: 1270 case NBACKGND: 1271 cmdtxt(n->nredir.n); 1272 break; 1273 case NIF: 1274 cmdputs("if "); 1275 cmdtxt(n->nif.test); 1276 cmdputs("; then "); 1277 cmdtxt(n->nif.ifpart); 1278 if (n->nif.elsepart) { 1279 cmdputs("; else "); 1280 cmdtxt(n->nif.elsepart); 1281 } 1282 cmdputs("; fi"); 1283 break; 1284 case NWHILE: 1285 cmdputs("while "); 1286 goto until; 1287 case NUNTIL: 1288 cmdputs("until "); 1289 until: 1290 cmdtxt(n->nbinary.ch1); 1291 cmdputs("; do "); 1292 cmdtxt(n->nbinary.ch2); 1293 cmdputs("; done"); 1294 break; 1295 case NFOR: 1296 cmdputs("for "); 1297 cmdputs(n->nfor.var); 1298 cmdputs(" in "); 1299 cmdlist(n->nfor.args, 1); 1300 cmdputs("; do "); 1301 cmdtxt(n->nfor.body); 1302 cmdputs("; done"); 1303 break; 1304 case NCASE: 1305 cmdputs("case "); 1306 cmdputs(n->ncase.expr->narg.text); 1307 cmdputs(" in "); 1308 for (np = n->ncase.cases; np; np = np->nclist.next) { 1309 cmdtxt(np->nclist.pattern); 1310 cmdputs(") "); 1311 cmdtxt(np->nclist.body); 1312 cmdputs(";; "); 1313 } 1314 cmdputs("esac"); 1315 break; 1316 case NDEFUN: 1317 cmdputs(n->narg.text); 1318 cmdputs("() { ... }"); 1319 break; 1320 case NCMD: 1321 cmdlist(n->ncmd.args, 1); 1322 cmdlist(n->ncmd.redirect, 0); 1323 break; 1324 case NARG: 1325 cmdputs(n->narg.text); 1326 break; 1327 case NTO: 1328 p = ">"; i = 1; goto redir; 1329 case NCLOBBER: 1330 p = ">|"; i = 1; goto redir; 1331 case NAPPEND: 1332 p = ">>"; i = 1; goto redir; 1333 case NTOFD: 1334 p = ">&"; i = 1; goto redir; 1335 case NFROM: 1336 p = "<"; i = 0; goto redir; 1337 case NFROMFD: 1338 p = "<&"; i = 0; goto redir; 1339 case NFROMTO: 1340 p = "<>"; i = 0; goto redir; 1341 redir: 1342 if (n->nfile.fd != i) { 1343 s[0] = n->nfile.fd + '0'; 1344 s[1] = '\0'; 1345 cmdputs(s); 1346 } 1347 cmdputs(p); 1348 if (n->type == NTOFD || n->type == NFROMFD) { 1349 s[0] = n->ndup.dupfd + '0'; 1350 s[1] = '\0'; 1351 cmdputs(s); 1352 } else { 1353 cmdtxt(n->nfile.fname); 1354 } 1355 break; 1356 case NHERE: 1357 case NXHERE: 1358 cmdputs("<<..."); 1359 break; 1360 default: 1361 cmdputs("???"); 1362 break; 1363 } 1364 } 1365 1366 STATIC void 1367 cmdlist(union node *np, int sep) 1368 { 1369 for (; np; np = np->narg.next) { 1370 if (!sep) 1371 cmdputs(" "); 1372 cmdtxt(np); 1373 if (sep && np->narg.next) 1374 cmdputs(" "); 1375 } 1376 } 1377 1378 1379 STATIC void 1380 cmdputs(const char *s) 1381 { 1382 const char *p, *str = 0; 1383 char c, cc[2] = " "; 1384 char *nextc; 1385 int nleft; 1386 int subtype = 0; 1387 int quoted = 0; 1388 static char vstype[16][4] = { "", "}", "-", "+", "?", "=", 1389 "#", "##", "%", "%%" }; 1390 1391 p = s; 1392 nextc = cmdnextc; 1393 nleft = cmdnleft; 1394 while (nleft > 0 && (c = *p++) != 0) { 1395 switch (c) { 1396 case CTLESC: 1397 c = *p++; 1398 break; 1399 case CTLVAR: 1400 subtype = *p++; 1401 if ((subtype & VSTYPE) == VSLENGTH) 1402 str = "${#"; 1403 else 1404 str = "${"; 1405 if (!(subtype & VSQUOTE) != !(quoted & 1)) { 1406 quoted ^= 1; 1407 c = '"'; 1408 } else 1409 c = *str++; 1410 break; 1411 case CTLENDVAR: 1412 if (quoted & 1) { 1413 c = '"'; 1414 str = "}"; 1415 } else 1416 c = '}'; 1417 quoted >>= 1; 1418 subtype = 0; 1419 break; 1420 case CTLBACKQ: 1421 c = '$'; 1422 str = "(...)"; 1423 break; 1424 case CTLBACKQ+CTLQUOTE: 1425 c = '"'; 1426 str = "$(...)\""; 1427 break; 1428 case CTLARI: 1429 c = '$'; 1430 str = "(("; 1431 break; 1432 case CTLENDARI: 1433 c = ')'; 1434 str = ")"; 1435 break; 1436 case CTLQUOTEMARK: 1437 quoted ^= 1; 1438 c = '"'; 1439 break; 1440 case '=': 1441 if (subtype == 0) 1442 break; 1443 str = vstype[subtype & VSTYPE]; 1444 if (subtype & VSNUL) 1445 c = ':'; 1446 else 1447 c = *str++; 1448 if (c != '}') 1449 quoted <<= 1; 1450 break; 1451 case '\'': 1452 case '\\': 1453 case '"': 1454 case '$': 1455 /* These can only happen inside quotes */ 1456 cc[0] = c; 1457 str = cc; 1458 c = '\\'; 1459 break; 1460 default: 1461 break; 1462 } 1463 do { 1464 *nextc++ = c; 1465 } while (--nleft > 0 && str && (c = *str++)); 1466 str = 0; 1467 } 1468 if ((quoted & 1) && nleft) { 1469 *nextc++ = '"'; 1470 nleft--; 1471 } 1472 cmdnleft = nleft; 1473 cmdnextc = nextc; 1474 } 1475