sh: Reduce more needless differences between error messages.
[dragonfly.git] / bin / sh / jobs.c
CommitLineData
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1/*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
1de703da
MD
35 *
36 * @(#)jobs.c 8.5 (Berkeley) 5/4/95
f893ef22 37 * $FreeBSD: src/bin/sh/jobs.c,v 1.93 2011/06/04 15:05:52 jilles Exp $
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38 */
39
99512ac4 40#include <sys/ioctl.h>
984263bc 41#include <sys/param.h>
984263bc 42#include <sys/resource.h>
99512ac4
PA
43#include <sys/time.h>
44#include <sys/wait.h>
45#include <errno.h>
46#include <fcntl.h>
984263bc 47#include <paths.h>
99512ac4
PA
48#include <signal.h>
49#include <stddef.h>
50#include <stdlib.h>
51#include <unistd.h>
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52
53#include "shell.h"
54#if JOBS
55#include <termios.h>
56#undef CEOF /* syntax.h redefines this */
57#endif
58#include "redir.h"
59#include "show.h"
60#include "main.h"
61#include "parser.h"
62#include "nodes.h"
63#include "jobs.h"
64#include "options.h"
65#include "trap.h"
66#include "syntax.h"
67#include "input.h"
68#include "output.h"
69#include "memalloc.h"
70#include "error.h"
71#include "mystring.h"
72
73
99512ac4
PA
74static struct job *jobtab; /* array of jobs */
75static int njobs; /* size of array */
984263bc 76MKINIT pid_t backgndpid = -1; /* pid of last background process */
99512ac4 77MKINIT struct job *bgjob = NULL; /* last background process */
984263bc 78#if JOBS
99512ac4
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79static struct job *jobmru; /* most recently used job list */
80static pid_t initialpgrp; /* pgrp of shell on invocation */
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81#endif
82int in_waitcmd = 0; /* are we in waitcmd()? */
83int in_dowait = 0; /* are we in dowait()? */
84volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */
85static int ttyfd = -1;
86
87#if JOBS
99512ac4 88static void restartjob(struct job *);
984263bc 89#endif
99512ac4
PA
90static void freejob(struct job *);
91static struct job *getjob(char *);
92static pid_t dowait(int, struct job *);
93static pid_t waitproc(int, int *);
94static void checkzombies(void);
95static void cmdtxt(union node *);
96static void cmdputs(const char *);
984263bc 97#if JOBS
99512ac4
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98static void setcurjob(struct job *);
99static void deljob(struct job *);
100static struct job *getcurjob(struct job *);
984263bc 101#endif
99512ac4
PA
102static void printjobcmd(struct job *);
103static void showjob(struct job *, int);
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104
105
106/*
107 * Turn job control on and off.
108 */
109
110MKINIT int jobctl;
111
112#if JOBS
113void
114setjobctl(int on)
115{
116 int i;
117
118 if (on == jobctl || rootshell == 0)
119 return;
120 if (on) {
121 if (ttyfd != -1)
122 close(ttyfd);
123 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) {
124 i = 0;
125 while (i <= 2 && !isatty(i))
126 i++;
127 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0)
128 goto out;
129 }
130 if (ttyfd < 10) {
131 /*
132 * Keep our TTY file descriptor out of the way of
133 * the user's redirections.
134 */
135 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) {
136 close(ttyfd);
137 ttyfd = -1;
138 goto out;
139 }
140 close(ttyfd);
141 ttyfd = i;
142 }
143 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) {
144 close(ttyfd);
145 ttyfd = -1;
146 goto out;
147 }
148 do { /* while we are in the background */
149 initialpgrp = tcgetpgrp(ttyfd);
150 if (initialpgrp < 0) {
99512ac4 151out: out2fmt_flush("sh: can't access tty; job control turned off\n");
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152 mflag = 0;
153 return;
154 }
99512ac4
PA
155 if (initialpgrp != getpgrp()) {
156 kill(0, SIGTTIN);
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157 continue;
158 }
159 } while (0);
160 setsignal(SIGTSTP);
161 setsignal(SIGTTOU);
162 setsignal(SIGTTIN);
163 setpgid(0, rootpid);
164 tcsetpgrp(ttyfd, rootpid);
165 } else { /* turning job control off */
166 setpgid(0, initialpgrp);
167 tcsetpgrp(ttyfd, initialpgrp);
168 close(ttyfd);
169 ttyfd = -1;
170 setsignal(SIGTSTP);
171 setsignal(SIGTTOU);
172 setsignal(SIGTTIN);
173 }
174 jobctl = on;
175}
176#endif
177
178
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179#if JOBS
180int
181fgcmd(int argc __unused, char **argv)
182{
183 struct job *jp;
184 pid_t pgrp;
185 int status;
186
187 jp = getjob(argv[1]);
188 if (jp->jobctl == 0)
189 error("job not created under job control");
99512ac4 190 printjobcmd(jp);
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191 flushout(&output);
192 pgrp = jp->ps[0].pid;
193 tcsetpgrp(ttyfd, pgrp);
194 restartjob(jp);
195 jp->foreground = 1;
196 INTOFF;
2038fb68 197 status = waitforjob(jp, NULL);
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198 INTON;
199 return status;
200}
201
202
203int
204bgcmd(int argc, char **argv)
205{
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206 struct job *jp;
207
208 do {
209 jp = getjob(*++argv);
210 if (jp->jobctl == 0)
211 error("job not created under job control");
212 if (jp->state == JOBDONE)
213 continue;
214 restartjob(jp);
215 jp->foreground = 0;
99512ac4
PA
216 out1fmt("[%td] ", jp - jobtab + 1);
217 printjobcmd(jp);
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218 } while (--argc > 1);
219 return 0;
220}
221
222
99512ac4 223static void
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224restartjob(struct job *jp)
225{
226 struct procstat *ps;
227 int i;
228
229 if (jp->state == JOBDONE)
230 return;
231 setcurjob(jp);
232 INTOFF;
99512ac4 233 kill(-jp->ps[0].pid, SIGCONT);
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234 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
235 if (WIFSTOPPED(ps->status)) {
236 ps->status = -1;
237 jp->state = 0;
238 }
239 }
240 INTON;
241}
242#endif
243
244
245int
246jobscmd(int argc, char *argv[])
247{
248 char *id;
9d7989de 249 int ch, mode;
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250
251 optind = optreset = 1;
252 opterr = 0;
9d7989de
PA
253 mode = SHOWJOBS_DEFAULT;
254 while ((ch = getopt(argc, argv, "lps")) != -1) {
984263bc
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255 switch (ch) {
256 case 'l':
9d7989de
PA
257 mode = SHOWJOBS_VERBOSE;
258 break;
259 case 'p':
260 mode = SHOWJOBS_PGIDS;
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261 break;
262 case 's':
9d7989de 263 mode = SHOWJOBS_PIDS;
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264 break;
265 case '?':
266 default:
267 error("unknown option: -%c", optopt);
268 }
269 }
270 argc -= optind;
271 argv += optind;
272
273 if (argc == 0)
9d7989de 274 showjobs(0, mode);
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275 else
276 while ((id = *argv++) != NULL)
99512ac4 277 showjob(getjob(id), mode);
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278
279 return (0);
280}
281
99512ac4
PA
282static void
283printjobcmd(struct job *jp)
284{
285 struct procstat *ps;
286 int i;
287
288 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
289 out1str(ps->cmd);
290 if (i > 0)
291 out1str(" | ");
292 }
293 out1c('\n');
294}
295
296static void
297showjob(struct job *jp, int mode)
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298{
299 char s[64];
99512ac4 300 char statestr[64];
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301 struct procstat *ps;
302 struct job *j;
303 int col, curr, i, jobno, prev, procno;
304 char c;
305
9d7989de 306 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs;
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307 jobno = jp - jobtab + 1;
308 curr = prev = 0;
309#if JOBS
310 if ((j = getcurjob(NULL)) != NULL) {
311 curr = j - jobtab + 1;
312 if ((j = getcurjob(j)) != NULL)
313 prev = j - jobtab + 1;
314 }
315#endif
99512ac4
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316 ps = jp->ps + jp->nprocs - 1;
317 if (jp->state == 0) {
318 strcpy(statestr, "Running");
319#if JOBS
320 } else if (jp->state == JOBSTOPPED) {
321 while (!WIFSTOPPED(ps->status) && ps > jp->ps)
322 ps--;
323 if (WIFSTOPPED(ps->status))
324 i = WSTOPSIG(ps->status);
325 else
326 i = -1;
327 if (i > 0 && i < sys_nsig && sys_siglist[i])
328 strcpy(statestr, sys_siglist[i]);
329 else
330 strcpy(statestr, "Suspended");
331#endif
332 } else if (WIFEXITED(ps->status)) {
333 if (WEXITSTATUS(ps->status) == 0)
334 strcpy(statestr, "Done");
335 else
336 fmtstr(statestr, 64, "Done(%d)",
337 WEXITSTATUS(ps->status));
338 } else {
339 i = WTERMSIG(ps->status);
340 if (i > 0 && i < sys_nsig && sys_siglist[i])
341 strcpy(statestr, sys_siglist[i]);
342 else
343 fmtstr(statestr, 64, "Signal %d", i);
344 if (WCOREDUMP(ps->status))
345 strcat(statestr, " (core dumped)");
346 }
347
984263bc 348 for (ps = jp->ps ; ; ps++) { /* for each process */
9d7989de 349 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) {
99512ac4 350 out1fmt("%d\n", (int)ps->pid);
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351 goto skip;
352 }
99512ac4 353 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps)
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354 goto skip;
355 if (jobno == curr && ps == jp->ps)
356 c = '+';
357 else if (jobno == prev && ps == jp->ps)
358 c = '-';
359 else
360 c = ' ';
361 if (ps == jp->ps)
362 fmtstr(s, 64, "[%d] %c ", jobno, c);
363 else
364 fmtstr(s, 64, " %c ", c);
365 out1str(s);
366 col = strlen(s);
9d7989de 367 if (mode == SHOWJOBS_VERBOSE) {
984263bc
MD
368 fmtstr(s, 64, "%d ", (int)ps->pid);
369 out1str(s);
370 col += strlen(s);
371 }
99512ac4
PA
372 if (ps == jp->ps) {
373 out1str(statestr);
374 col += strlen(statestr);
984263bc 375 }
984263bc
MD
376 do {
377 out1c(' ');
378 col++;
379 } while (col < 30);
99512ac4
PA
380 if (mode == SHOWJOBS_VERBOSE) {
381 out1str(ps->cmd);
382 out1c('\n');
383 } else
384 printjobcmd(jp);
984263bc
MD
385skip: if (--procno <= 0)
386 break;
387 }
388}
389
390/*
391 * Print a list of jobs. If "change" is nonzero, only print jobs whose
392 * statuses have changed since the last call to showjobs.
393 *
394 * If the shell is interrupted in the process of creating a job, the
395 * result may be a job structure containing zero processes. Such structures
396 * will be freed here.
397 */
398
399void
9d7989de 400showjobs(int change, int mode)
984263bc
MD
401{
402 int jobno;
403 struct job *jp;
404
405 TRACE(("showjobs(%d) called\n", change));
99512ac4 406 checkzombies();
984263bc
MD
407 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) {
408 if (! jp->used)
409 continue;
410 if (jp->nprocs == 0) {
411 freejob(jp);
412 continue;
413 }
414 if (change && ! jp->changed)
415 continue;
99512ac4 416 showjob(jp, mode);
984263bc 417 jp->changed = 0;
99512ac4
PA
418 /* Hack: discard jobs for which $! has not been referenced
419 * in interactive mode when they terminate.
420 */
421 if (jp->state == JOBDONE && !jp->remembered &&
422 (iflag || jp != bgjob)) {
984263bc
MD
423 freejob(jp);
424 }
425 }
426}
427
428
429/*
430 * Mark a job structure as unused.
431 */
432
99512ac4 433static void
984263bc
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434freejob(struct job *jp)
435{
436 struct procstat *ps;
437 int i;
438
439 INTOFF;
99512ac4
PA
440 if (bgjob == jp)
441 bgjob = NULL;
984263bc
MD
442 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) {
443 if (ps->cmd != nullstr)
444 ckfree(ps->cmd);
445 }
446 if (jp->ps != &jp->ps0)
447 ckfree(jp->ps);
448 jp->used = 0;
449#if JOBS
450 deljob(jp);
451#endif
452 INTON;
453}
454
455
456
457int
458waitcmd(int argc, char **argv)
459{
460 struct job *job;
461 int status, retval;
462 struct job *jp;
463
464 if (argc > 1) {
465 job = getjob(argv[1]);
466 } else {
467 job = NULL;
468 }
469
470 /*
471 * Loop until a process is terminated or stopped, or a SIGINT is
472 * received.
473 */
474
475 in_waitcmd++;
476 do {
477 if (job != NULL) {
478 if (job->state) {
479 status = job->ps[job->nprocs - 1].status;
480 if (WIFEXITED(status))
481 retval = WEXITSTATUS(status);
482#if JOBS
483 else if (WIFSTOPPED(status))
484 retval = WSTOPSIG(status) + 128;
485#endif
486 else
487 retval = WTERMSIG(status) + 128;
99512ac4 488 if (! iflag || ! job->changed)
984263bc 489 freejob(job);
99512ac4
PA
490 else {
491 job->remembered = 0;
492 if (job == bgjob)
493 bgjob = NULL;
494 }
984263bc
MD
495 in_waitcmd--;
496 return retval;
497 }
498 } else {
99512ac4
PA
499 for (jp = jobtab ; jp < jobtab + njobs; jp++)
500 if (jp->used && jp->state == JOBDONE) {
501 if (! iflag || ! jp->changed)
502 freejob(jp);
503 else {
504 jp->remembered = 0;
505 if (jp == bgjob)
506 bgjob = NULL;
507 }
508 }
984263bc
MD
509 for (jp = jobtab ; ; jp++) {
510 if (jp >= jobtab + njobs) { /* no running procs */
511 in_waitcmd--;
512 return 0;
513 }
514 if (jp->used && jp->state == 0)
515 break;
516 }
517 }
2038fb68 518 } while (dowait(1, NULL) != -1);
984263bc
MD
519 in_waitcmd--;
520
521 return 0;
522}
523
524
525
526int
527jobidcmd(int argc __unused, char **argv)
528{
529 struct job *jp;
530 int i;
531
532 jp = getjob(argv[1]);
533 for (i = 0 ; i < jp->nprocs ; ) {
534 out1fmt("%d", (int)jp->ps[i].pid);
535 out1c(++i < jp->nprocs? ' ' : '\n');
536 }
537 return 0;
538}
539
540
541
542/*
543 * Convert a job name to a job structure.
544 */
545
99512ac4 546static struct job *
984263bc
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547getjob(char *name)
548{
549 int jobno;
550 struct job *found, *jp;
551 pid_t pid;
552 int i;
553
554 if (name == NULL) {
555#if JOBS
556currentjob: if ((jp = getcurjob(NULL)) == NULL)
557 error("No current job");
558 return (jp);
559#else
560 error("No current job");
561#endif
562 } else if (name[0] == '%') {
563 if (is_digit(name[1])) {
564 jobno = number(name + 1);
565 if (jobno > 0 && jobno <= njobs
566 && jobtab[jobno - 1].used != 0)
567 return &jobtab[jobno - 1];
568#if JOBS
569 } else if (name[1] == '%' && name[2] == '\0') {
570 goto currentjob;
571 } else if (name[1] == '+' && name[2] == '\0') {
572 goto currentjob;
573 } else if (name[1] == '-' && name[2] == '\0') {
574 if ((jp = getcurjob(NULL)) == NULL ||
575 (jp = getcurjob(jp)) == NULL)
576 error("No previous job");
577 return (jp);
578#endif
579 } else if (name[1] == '?') {
580 found = NULL;
581 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
582 if (jp->used && jp->nprocs > 0
583 && strstr(jp->ps[0].cmd, name + 2) != NULL) {
584 if (found)
585 error("%s: ambiguous", name);
586 found = jp;
587 }
588 }
589 if (found != NULL)
590 return (found);
591 } else {
592 found = NULL;
593 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
594 if (jp->used && jp->nprocs > 0
595 && prefix(name + 1, jp->ps[0].cmd)) {
596 if (found)
597 error("%s: ambiguous", name);
598 found = jp;
599 }
600 }
601 if (found)
602 return found;
603 }
604 } else if (is_number(name)) {
605 pid = (pid_t)number(name);
606 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
607 if (jp->used && jp->nprocs > 0
608 && jp->ps[jp->nprocs - 1].pid == pid)
609 return jp;
610 }
611 }
612 error("No such job: %s", name);
613 /*NOTREACHED*/
614 return NULL;
615}
616
617
99512ac4
PA
618pid_t
619getjobpgrp(char *name)
620{
621 struct job *jp;
622
623 jp = getjob(name);
624 return -jp->ps[0].pid;
625}
984263bc
MD
626
627/*
628 * Return a new job structure,
629 */
630
631struct job *
632makejob(union node *node __unused, int nprocs)
633{
634 int i;
635 struct job *jp;
636
637 for (i = njobs, jp = jobtab ; ; jp++) {
638 if (--i < 0) {
639 INTOFF;
640 if (njobs == 0) {
641 jobtab = ckmalloc(4 * sizeof jobtab[0]);
642#if JOBS
643 jobmru = NULL;
644#endif
645 } else {
646 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
647 memcpy(jp, jobtab, njobs * sizeof jp[0]);
648#if JOBS
649 /* Relocate `next' pointers and list head */
650 if (jobmru != NULL)
651 jobmru = &jp[jobmru - jobtab];
652 for (i = 0; i < njobs; i++)
653 if (jp[i].next != NULL)
654 jp[i].next = &jp[jp[i].next -
655 jobtab];
656#endif
99512ac4
PA
657 if (bgjob != NULL)
658 bgjob = &jp[bgjob - jobtab];
984263bc
MD
659 /* Relocate `ps' pointers */
660 for (i = 0; i < njobs; i++)
661 if (jp[i].ps == &jobtab[i].ps0)
662 jp[i].ps = &jp[i].ps0;
663 ckfree(jobtab);
664 jobtab = jp;
665 }
666 jp = jobtab + njobs;
667 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0);
668 INTON;
669 break;
670 }
671 if (jp->used == 0)
672 break;
673 }
674 INTOFF;
675 jp->state = 0;
676 jp->used = 1;
677 jp->changed = 0;
678 jp->nprocs = 0;
679 jp->foreground = 0;
99512ac4 680 jp->remembered = 0;
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681#if JOBS
682 jp->jobctl = jobctl;
683 jp->next = NULL;
684#endif
685 if (nprocs > 1) {
686 jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
687 } else {
688 jp->ps = &jp->ps0;
689 }
690 INTON;
99512ac4 691 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs,
984263bc
MD
692 jp - jobtab + 1));
693 return jp;
694}
695
696#if JOBS
99512ac4 697static void
984263bc
MD
698setcurjob(struct job *cj)
699{
700 struct job *jp, *prev;
701
702 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
703 if (jp == cj) {
704 if (prev != NULL)
705 prev->next = jp->next;
706 else
707 jobmru = jp->next;
708 jp->next = jobmru;
709 jobmru = cj;
710 return;
711 }
712 }
713 cj->next = jobmru;
714 jobmru = cj;
715}
716
99512ac4 717static void
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MD
718deljob(struct job *j)
719{
720 struct job *jp, *prev;
721
722 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
723 if (jp == j) {
724 if (prev != NULL)
725 prev->next = jp->next;
726 else
727 jobmru = jp->next;
728 return;
729 }
730 }
731}
732
733/*
734 * Return the most recently used job that isn't `nj', and preferably one
735 * that is stopped.
736 */
99512ac4 737static struct job *
984263bc
MD
738getcurjob(struct job *nj)
739{
740 struct job *jp;
741
742 /* Try to find a stopped one.. */
743 for (jp = jobmru; jp != NULL; jp = jp->next)
744 if (jp->used && jp != nj && jp->state == JOBSTOPPED)
745 return (jp);
746 /* Otherwise the most recently used job that isn't `nj' */
747 for (jp = jobmru; jp != NULL; jp = jp->next)
748 if (jp->used && jp != nj)
749 return (jp);
750
751 return (NULL);
752}
753
754#endif
755
756/*
757 * Fork of a subshell. If we are doing job control, give the subshell its
758 * own process group. Jp is a job structure that the job is to be added to.
759 * N is the command that will be evaluated by the child. Both jp and n may
760 * be NULL. The mode parameter can be one of the following:
761 * FORK_FG - Fork off a foreground process.
762 * FORK_BG - Fork off a background process.
763 * FORK_NOJOB - Like FORK_FG, but don't give the process its own
764 * process group even if job control is on.
765 *
766 * When job control is turned off, background processes have their standard
767 * input redirected to /dev/null (except for the second and later processes
768 * in a pipeline).
769 */
770
771pid_t
772forkshell(struct job *jp, union node *n, int mode)
773{
774 pid_t pid;
775 pid_t pgrp;
776
99512ac4 777 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n,
984263bc
MD
778 mode));
779 INTOFF;
99512ac4
PA
780 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0))
781 checkzombies();
984263bc
MD
782 flushall();
783 pid = fork();
784 if (pid == -1) {
785 TRACE(("Fork failed, errno=%d\n", errno));
786 INTON;
787 error("Cannot fork: %s", strerror(errno));
788 }
789 if (pid == 0) {
790 struct job *p;
791 int wasroot;
792 int i;
793
794 TRACE(("Child shell %d\n", (int)getpid()));
795 wasroot = rootshell;
796 rootshell = 0;
99512ac4 797 handler = &main_handler;
984263bc
MD
798 closescript();
799 INTON;
800 clear_traps();
801#if JOBS
802 jobctl = 0; /* do job control only in root shell */
803 if (wasroot && mode != FORK_NOJOB && mflag) {
804 if (jp == NULL || jp->nprocs == 0)
805 pgrp = getpid();
806 else
807 pgrp = jp->ps[0].pid;
808 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) {
809 /*** this causes superfluous TIOCSPGRPS ***/
810 if (tcsetpgrp(ttyfd, pgrp) < 0)
811 error("tcsetpgrp failed, errno=%d", errno);
812 }
813 setsignal(SIGTSTP);
814 setsignal(SIGTTOU);
815 } else if (mode == FORK_BG) {
816 ignoresig(SIGINT);
817 ignoresig(SIGQUIT);
818 if ((jp == NULL || jp->nprocs == 0) &&
819 ! fd0_redirected_p ()) {
820 close(0);
821 if (open(_PATH_DEVNULL, O_RDONLY) != 0)
f893ef22 822 error("cannot open %s: %s",
984263bc
MD
823 _PATH_DEVNULL, strerror(errno));
824 }
825 }
826#else
827 if (mode == FORK_BG) {
828 ignoresig(SIGINT);
829 ignoresig(SIGQUIT);
830 if ((jp == NULL || jp->nprocs == 0) &&
831 ! fd0_redirected_p ()) {
832 close(0);
833 if (open(_PATH_DEVNULL, O_RDONLY) != 0)
f893ef22 834 error("cannot open %s: %s",
984263bc
MD
835 _PATH_DEVNULL, strerror(errno));
836 }
837 }
838#endif
839 INTOFF;
840 for (i = njobs, p = jobtab ; --i >= 0 ; p++)
841 if (p->used)
842 freejob(p);
843 INTON;
844 if (wasroot && iflag) {
845 setsignal(SIGINT);
846 setsignal(SIGQUIT);
847 setsignal(SIGTERM);
848 }
849 return pid;
850 }
851 if (rootshell && mode != FORK_NOJOB && mflag) {
852 if (jp == NULL || jp->nprocs == 0)
853 pgrp = pid;
854 else
855 pgrp = jp->ps[0].pid;
856 setpgid(pid, pgrp);
857 }
99512ac4
PA
858 if (mode == FORK_BG) {
859 if (bgjob != NULL && bgjob->state == JOBDONE &&
860 !bgjob->remembered && !iflag)
861 freejob(bgjob);
984263bc 862 backgndpid = pid; /* set $! */
99512ac4
PA
863 bgjob = jp;
864 }
984263bc
MD
865 if (jp) {
866 struct procstat *ps = &jp->ps[jp->nprocs++];
867 ps->pid = pid;
868 ps->status = -1;
869 ps->cmd = nullstr;
870 if (iflag && rootshell && n)
871 ps->cmd = commandtext(n);
872 jp->foreground = mode == FORK_FG;
873#if JOBS
874 setcurjob(jp);
875#endif
876 }
877 INTON;
878 TRACE(("In parent shell: child = %d\n", (int)pid));
879 return pid;
880}
881
882
883
884/*
885 * Wait for job to finish.
886 *
887 * Under job control we have the problem that while a child process is
888 * running interrupts generated by the user are sent to the child but not
889 * to the shell. This means that an infinite loop started by an inter-
890 * active user may be hard to kill. With job control turned off, an
891 * interactive user may place an interactive program inside a loop. If
892 * the interactive program catches interrupts, the user doesn't want
893 * these interrupts to also abort the loop. The approach we take here
894 * is to have the shell ignore interrupt signals while waiting for a
895 * foreground process to terminate, and then send itself an interrupt
896 * signal if the child process was terminated by an interrupt signal.
897 * Unfortunately, some programs want to do a bit of cleanup and then
898 * exit on interrupt; unless these processes terminate themselves by
899 * sending a signal to themselves (instead of calling exit) they will
900 * confuse this approach.
901 */
902
903int
904waitforjob(struct job *jp, int *origstatus)
905{
906#if JOBS
907 pid_t mypgrp = getpgrp();
99512ac4 908 int propagate_int = jp->jobctl && jp->foreground;
984263bc
MD
909#endif
910 int status;
911 int st;
912
913 INTOFF;
99512ac4 914 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1));
984263bc
MD
915 while (jp->state == 0)
916 if (dowait(1, jp) == -1)
917 dotrap();
918#if JOBS
919 if (jp->jobctl) {
920 if (tcsetpgrp(ttyfd, mypgrp) < 0)
921 error("tcsetpgrp failed, errno=%d\n", errno);
922 }
923 if (jp->state == JOBSTOPPED)
924 setcurjob(jp);
925#endif
926 status = jp->ps[jp->nprocs - 1].status;
927 if (origstatus != NULL)
928 *origstatus = status;
929 /* convert to 8 bits */
930 if (WIFEXITED(status))
931 st = WEXITSTATUS(status);
932#if JOBS
933 else if (WIFSTOPPED(status))
934 st = WSTOPSIG(status) + 128;
935#endif
936 else
937 st = WTERMSIG(status) + 128;
938 if (! JOBS || jp->state == JOBDONE)
939 freejob(jp);
940 if (int_pending()) {
99512ac4 941 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT)
984263bc
MD
942 CLEAR_PENDING_INT;
943 }
99512ac4
PA
944#if JOBS
945 else if (rootshell && iflag && propagate_int &&
946 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
947 kill(getpid(), SIGINT);
948#endif
984263bc
MD
949 INTON;
950 return st;
951}
952
953
954
955/*
956 * Wait for a process to terminate.
957 */
958
99512ac4 959static pid_t
984263bc
MD
960dowait(int block, struct job *job)
961{
962 pid_t pid;
963 int status;
964 struct procstat *sp;
965 struct job *jp;
966 struct job *thisjob;
967 int done;
968 int stopped;
969 int sig;
99512ac4 970 int coredump;
984263bc
MD
971
972 in_dowait++;
973 TRACE(("dowait(%d) called\n", block));
974 do {
975 pid = waitproc(block, &status);
976 TRACE(("wait returns %d, status=%d\n", (int)pid, status));
977 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) ||
fc88d1a0 978 (pid > 0 && WIFSTOPPED(status) && !iflag));
984263bc 979 in_dowait--;
fc88d1a0
PA
980 if (pid == -1 && errno == ECHILD && job != NULL)
981 job->state = JOBDONE;
984263bc
MD
982 if (breakwaitcmd != 0) {
983 breakwaitcmd = 0;
7c9c5302
MD
984 /*
985 * Do not early terminate if the pid is positive, else the
986 * job will not be properly recorded.
987 */
988 if (pid <= 0)
989 return -1;
984263bc
MD
990 }
991 if (pid <= 0)
992 return pid;
993 INTOFF;
994 thisjob = NULL;
995 for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
99512ac4 996 if (jp->used && jp->nprocs > 0) {
984263bc
MD
997 done = 1;
998 stopped = 1;
999 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
1000 if (sp->pid == -1)
1001 continue;
1002 if (sp->pid == pid) {
1003 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n",
1004 (int)pid, sp->status,
1005 status));
1006 sp->status = status;
1007 thisjob = jp;
1008 }
1009 if (sp->status == -1)
1010 stopped = 0;
1011 else if (WIFSTOPPED(sp->status))
1012 done = 0;
1013 }
1014 if (stopped) { /* stopped or done */
1015 int state = done? JOBDONE : JOBSTOPPED;
1016 if (jp->state != state) {
99512ac4 1017 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
984263bc 1018 jp->state = state;
99512ac4
PA
1019 if (jp != job) {
1020 if (done && !jp->remembered &&
1021 !iflag && jp != bgjob)
1022 freejob(jp);
984263bc 1023#if JOBS
99512ac4
PA
1024 else if (done)
1025 deljob(jp);
984263bc 1026#endif
99512ac4 1027 }
984263bc
MD
1028 }
1029 }
1030 }
1031 }
1032 INTON;
99512ac4
PA
1033 if (!thisjob || thisjob->state == 0)
1034 ;
1035 else if ((!rootshell || !iflag || thisjob == job) &&
1036 thisjob->foreground && thisjob->state != JOBSTOPPED) {
1037 sig = 0;
1038 coredump = 0;
1039 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++)
1040 if (WIFSIGNALED(sp->status)) {
1041 sig = WTERMSIG(sp->status);
1042 coredump = WCOREDUMP(sp->status);
1043 }
1044 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) {
1045 if (sig < sys_nsig && sys_siglist[sig])
1046 out2str(sys_siglist[sig]);
984263bc 1047 else
99512ac4
PA
1048 outfmt(out2, "Signal %d", sig);
1049 if (coredump)
1050 out2str(" (core dumped)");
1051 out2c('\n');
1052 flushout(out2);
984263bc
MD
1053 }
1054 } else {
fc88d1a0 1055 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job));
99512ac4 1056 thisjob->changed = 1;
984263bc
MD
1057 }
1058 return pid;
1059}
1060
1061
1062
1063/*
1064 * Do a wait system call. If job control is compiled in, we accept
1065 * stopped processes. If block is zero, we return a value of zero
1066 * rather than blocking.
1067 */
99512ac4 1068static pid_t
984263bc
MD
1069waitproc(int block, int *status)
1070{
1071 int flags;
1072
1073#if JOBS
1074 flags = WUNTRACED;
1075#else
1076 flags = 0;
1077#endif
1078 if (block == 0)
1079 flags |= WNOHANG;
2038fb68 1080 return wait3(status, flags, NULL);
984263bc
MD
1081}
1082
1083/*
1084 * return 1 if there are stopped jobs, otherwise 0
1085 */
1086int job_warning = 0;
1087int
1088stoppedjobs(void)
1089{
1090 int jobno;
1091 struct job *jp;
1092
1093 if (job_warning)
1094 return (0);
1095 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) {
1096 if (jp->used == 0)
1097 continue;
1098 if (jp->state == JOBSTOPPED) {
99512ac4 1099 out2fmt_flush("You have stopped jobs.\n");
984263bc
MD
1100 job_warning = 2;
1101 return (1);
1102 }
1103 }
1104
1105 return (0);
1106}
1107
99512ac4
PA
1108
1109static void
1110checkzombies(void)
1111{
1112 while (njobs > 0 && dowait(0, NULL) > 0)
1113 ;
1114}
1115
1116
1117int
1118backgndpidset(void)
1119{
1120 return backgndpid != -1;
1121}
1122
1123
1124pid_t
1125backgndpidval(void)
1126{
1127 if (bgjob != NULL)
1128 bgjob->remembered = 1;
1129 return backgndpid;
1130}
1131
984263bc
MD
1132/*
1133 * Return a string identifying a command (to be printed by the
1134 * jobs command.
1135 */
1136
99512ac4
PA
1137static char *cmdnextc;
1138static int cmdnleft;
984263bc
MD
1139#define MAXCMDTEXT 200
1140
1141char *
1142commandtext(union node *n)
1143{
1144 char *name;
1145
1146 cmdnextc = name = ckmalloc(MAXCMDTEXT);
1147 cmdnleft = MAXCMDTEXT - 4;
1148 cmdtxt(n);
1149 *cmdnextc = '\0';
1150 return name;
1151}
1152
1153
99512ac4 1154static void
984263bc
MD
1155cmdtxt(union node *n)
1156{
1157 union node *np;
1158 struct nodelist *lp;
492efe05 1159 const char *p;
984263bc
MD
1160 int i;
1161 char s[2];
1162
1163 if (n == NULL)
1164 return;
1165 switch (n->type) {
1166 case NSEMI:
1167 cmdtxt(n->nbinary.ch1);
1168 cmdputs("; ");
1169 cmdtxt(n->nbinary.ch2);
1170 break;
1171 case NAND:
1172 cmdtxt(n->nbinary.ch1);
1173 cmdputs(" && ");
1174 cmdtxt(n->nbinary.ch2);
1175 break;
1176 case NOR:
1177 cmdtxt(n->nbinary.ch1);
1178 cmdputs(" || ");
1179 cmdtxt(n->nbinary.ch2);
1180 break;
1181 case NPIPE:
1182 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
1183 cmdtxt(lp->n);
1184 if (lp->next)
1185 cmdputs(" | ");
1186 }
1187 break;
1188 case NSUBSHELL:
1189 cmdputs("(");
1190 cmdtxt(n->nredir.n);
1191 cmdputs(")");
1192 break;
1193 case NREDIR:
1194 case NBACKGND:
1195 cmdtxt(n->nredir.n);
1196 break;
1197 case NIF:
1198 cmdputs("if ");
1199 cmdtxt(n->nif.test);
1200 cmdputs("; then ");
1201 cmdtxt(n->nif.ifpart);
1202 cmdputs("...");
1203 break;
1204 case NWHILE:
1205 cmdputs("while ");
1206 goto until;
1207 case NUNTIL:
1208 cmdputs("until ");
1209until:
1210 cmdtxt(n->nbinary.ch1);
1211 cmdputs("; do ");
1212 cmdtxt(n->nbinary.ch2);
1213 cmdputs("; done");
1214 break;
1215 case NFOR:
1216 cmdputs("for ");
1217 cmdputs(n->nfor.var);
1218 cmdputs(" in ...");
1219 break;
1220 case NCASE:
1221 cmdputs("case ");
1222 cmdputs(n->ncase.expr->narg.text);
1223 cmdputs(" in ...");
1224 break;
1225 case NDEFUN:
1226 cmdputs(n->narg.text);
1227 cmdputs("() ...");
1228 break;
1229 case NCMD:
1230 for (np = n->ncmd.args ; np ; np = np->narg.next) {
1231 cmdtxt(np);
1232 if (np->narg.next)
1233 cmdputs(" ");
1234 }
1235 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) {
1236 cmdputs(" ");
1237 cmdtxt(np);
1238 }
1239 break;
1240 case NARG:
1241 cmdputs(n->narg.text);
1242 break;
1243 case NTO:
1244 p = ">"; i = 1; goto redir;
1245 case NAPPEND:
1246 p = ">>"; i = 1; goto redir;
1247 case NTOFD:
1248 p = ">&"; i = 1; goto redir;
1249 case NCLOBBER:
1250 p = ">|"; i = 1; goto redir;
1251 case NFROM:
1252 p = "<"; i = 0; goto redir;
1253 case NFROMTO:
1254 p = "<>"; i = 0; goto redir;
1255 case NFROMFD:
1256 p = "<&"; i = 0; goto redir;
1257redir:
1258 if (n->nfile.fd != i) {
1259 s[0] = n->nfile.fd + '0';
1260 s[1] = '\0';
1261 cmdputs(s);
1262 }
1263 cmdputs(p);
1264 if (n->type == NTOFD || n->type == NFROMFD) {
1265 if (n->ndup.dupfd >= 0)
1266 s[0] = n->ndup.dupfd + '0';
1267 else
1268 s[0] = '-';
1269 s[1] = '\0';
1270 cmdputs(s);
1271 } else {
1272 cmdtxt(n->nfile.fname);
1273 }
1274 break;
1275 case NHERE:
1276 case NXHERE:
1277 cmdputs("<<...");
1278 break;
1279 default:
1280 cmdputs("???");
1281 break;
1282 }
1283}
1284
1285
1286
99512ac4 1287static void
492efe05 1288cmdputs(const char *s)
984263bc 1289{
492efe05
CP
1290 const char *p;
1291 char *q;
984263bc
MD
1292 char c;
1293 int subtype = 0;
1294
1295 if (cmdnleft <= 0)
1296 return;
1297 p = s;
1298 q = cmdnextc;
1299 while ((c = *p++) != '\0') {
1300 if (c == CTLESC)
1301 *q++ = *p++;
1302 else if (c == CTLVAR) {
1303 *q++ = '$';
1304 if (--cmdnleft > 0)
1305 *q++ = '{';
1306 subtype = *p++;
99512ac4
PA
1307 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0)
1308 *q++ = '#';
984263bc 1309 } else if (c == '=' && subtype != 0) {
99512ac4
PA
1310 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL];
1311 if (*q)
1312 q++;
1313 else
1314 cmdnleft++;
1315 if (((subtype & VSTYPE) == VSTRIMLEFTMAX ||
1316 (subtype & VSTYPE) == VSTRIMRIGHTMAX) &&
1317 --cmdnleft > 0)
1318 *q = q[-1], q++;
984263bc
MD
1319 subtype = 0;
1320 } else if (c == CTLENDVAR) {
1321 *q++ = '}';
99512ac4
PA
1322 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) {
1323 cmdnleft -= 5;
1324 if (cmdnleft > 0) {
1325 *q++ = '$';
1326 *q++ = '(';
1327 *q++ = '.';
1328 *q++ = '.';
1329 *q++ = '.';
1330 *q++ = ')';
1331 }
1332 } else if (c == CTLARI) {
1333 cmdnleft -= 2;
1334 if (cmdnleft > 0) {
1335 *q++ = '$';
1336 *q++ = '(';
1337 *q++ = '(';
1338 }
1339 p++;
1340 } else if (c == CTLENDARI) {
1341 if (--cmdnleft > 0) {
1342 *q++ = ')';
1343 *q++ = ')';
1344 }
1345 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND)
1346 cmdnleft++; /* ignore */
984263bc
MD
1347 else
1348 *q++ = c;
1349 if (--cmdnleft <= 0) {
1350 *q++ = '.';
1351 *q++ = '.';
1352 *q++ = '.';
1353 break;
1354 }
1355 }
1356 cmdnextc = q;
1357}