sh: Save/restore changed variables in optimized command substitution.
[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
32931063 37 * $FreeBSD: src/bin/sh/jobs.c,v 1.94 2011/06/12 23:06:04 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"
32931063 72#include "var.h"
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73
74
99512ac4
PA
75static struct job *jobtab; /* array of jobs */
76static int njobs; /* size of array */
984263bc 77MKINIT pid_t backgndpid = -1; /* pid of last background process */
99512ac4 78MKINIT struct job *bgjob = NULL; /* last background process */
984263bc 79#if JOBS
99512ac4
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80static struct job *jobmru; /* most recently used job list */
81static pid_t initialpgrp; /* pgrp of shell on invocation */
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82#endif
83int in_waitcmd = 0; /* are we in waitcmd()? */
84int in_dowait = 0; /* are we in dowait()? */
85volatile sig_atomic_t breakwaitcmd = 0; /* should wait be terminated? */
86static int ttyfd = -1;
87
88#if JOBS
99512ac4 89static void restartjob(struct job *);
984263bc 90#endif
99512ac4
PA
91static void freejob(struct job *);
92static struct job *getjob(char *);
93static pid_t dowait(int, struct job *);
94static pid_t waitproc(int, int *);
95static void checkzombies(void);
96static void cmdtxt(union node *);
97static void cmdputs(const char *);
984263bc 98#if JOBS
99512ac4
PA
99static void setcurjob(struct job *);
100static void deljob(struct job *);
101static struct job *getcurjob(struct job *);
984263bc 102#endif
99512ac4
PA
103static void printjobcmd(struct job *);
104static void showjob(struct job *, int);
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105
106
107/*
108 * Turn job control on and off.
109 */
110
111MKINIT int jobctl;
112
113#if JOBS
114void
115setjobctl(int on)
116{
117 int i;
118
119 if (on == jobctl || rootshell == 0)
120 return;
121 if (on) {
122 if (ttyfd != -1)
123 close(ttyfd);
124 if ((ttyfd = open(_PATH_TTY, O_RDWR)) < 0) {
125 i = 0;
126 while (i <= 2 && !isatty(i))
127 i++;
128 if (i > 2 || (ttyfd = fcntl(i, F_DUPFD, 10)) < 0)
129 goto out;
130 }
131 if (ttyfd < 10) {
132 /*
133 * Keep our TTY file descriptor out of the way of
134 * the user's redirections.
135 */
136 if ((i = fcntl(ttyfd, F_DUPFD, 10)) < 0) {
137 close(ttyfd);
138 ttyfd = -1;
139 goto out;
140 }
141 close(ttyfd);
142 ttyfd = i;
143 }
144 if (fcntl(ttyfd, F_SETFD, FD_CLOEXEC) < 0) {
145 close(ttyfd);
146 ttyfd = -1;
147 goto out;
148 }
149 do { /* while we are in the background */
150 initialpgrp = tcgetpgrp(ttyfd);
151 if (initialpgrp < 0) {
99512ac4 152out: out2fmt_flush("sh: can't access tty; job control turned off\n");
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153 mflag = 0;
154 return;
155 }
99512ac4
PA
156 if (initialpgrp != getpgrp()) {
157 kill(0, SIGTTIN);
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158 continue;
159 }
160 } while (0);
161 setsignal(SIGTSTP);
162 setsignal(SIGTTOU);
163 setsignal(SIGTTIN);
164 setpgid(0, rootpid);
165 tcsetpgrp(ttyfd, rootpid);
166 } else { /* turning job control off */
167 setpgid(0, initialpgrp);
168 tcsetpgrp(ttyfd, initialpgrp);
169 close(ttyfd);
170 ttyfd = -1;
171 setsignal(SIGTSTP);
172 setsignal(SIGTTOU);
173 setsignal(SIGTTIN);
174 }
175 jobctl = on;
176}
177#endif
178
179
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180#if JOBS
181int
182fgcmd(int argc __unused, char **argv)
183{
184 struct job *jp;
185 pid_t pgrp;
186 int status;
187
188 jp = getjob(argv[1]);
189 if (jp->jobctl == 0)
190 error("job not created under job control");
99512ac4 191 printjobcmd(jp);
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192 flushout(&output);
193 pgrp = jp->ps[0].pid;
194 tcsetpgrp(ttyfd, pgrp);
195 restartjob(jp);
196 jp->foreground = 1;
197 INTOFF;
2038fb68 198 status = waitforjob(jp, NULL);
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199 INTON;
200 return status;
201}
202
203
204int
205bgcmd(int argc, char **argv)
206{
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207 struct job *jp;
208
209 do {
210 jp = getjob(*++argv);
211 if (jp->jobctl == 0)
212 error("job not created under job control");
213 if (jp->state == JOBDONE)
214 continue;
215 restartjob(jp);
216 jp->foreground = 0;
99512ac4
PA
217 out1fmt("[%td] ", jp - jobtab + 1);
218 printjobcmd(jp);
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219 } while (--argc > 1);
220 return 0;
221}
222
223
99512ac4 224static void
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225restartjob(struct job *jp)
226{
227 struct procstat *ps;
228 int i;
229
230 if (jp->state == JOBDONE)
231 return;
232 setcurjob(jp);
233 INTOFF;
99512ac4 234 kill(-jp->ps[0].pid, SIGCONT);
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235 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
236 if (WIFSTOPPED(ps->status)) {
237 ps->status = -1;
238 jp->state = 0;
239 }
240 }
241 INTON;
242}
243#endif
244
245
246int
247jobscmd(int argc, char *argv[])
248{
249 char *id;
9d7989de 250 int ch, mode;
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251
252 optind = optreset = 1;
253 opterr = 0;
9d7989de
PA
254 mode = SHOWJOBS_DEFAULT;
255 while ((ch = getopt(argc, argv, "lps")) != -1) {
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256 switch (ch) {
257 case 'l':
9d7989de
PA
258 mode = SHOWJOBS_VERBOSE;
259 break;
260 case 'p':
261 mode = SHOWJOBS_PGIDS;
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262 break;
263 case 's':
9d7989de 264 mode = SHOWJOBS_PIDS;
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265 break;
266 case '?':
267 default:
268 error("unknown option: -%c", optopt);
269 }
270 }
271 argc -= optind;
272 argv += optind;
273
274 if (argc == 0)
9d7989de 275 showjobs(0, mode);
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276 else
277 while ((id = *argv++) != NULL)
99512ac4 278 showjob(getjob(id), mode);
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279
280 return (0);
281}
282
99512ac4
PA
283static void
284printjobcmd(struct job *jp)
285{
286 struct procstat *ps;
287 int i;
288
289 for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
290 out1str(ps->cmd);
291 if (i > 0)
292 out1str(" | ");
293 }
294 out1c('\n');
295}
296
297static void
298showjob(struct job *jp, int mode)
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299{
300 char s[64];
99512ac4 301 char statestr[64];
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302 struct procstat *ps;
303 struct job *j;
304 int col, curr, i, jobno, prev, procno;
305 char c;
306
9d7989de 307 procno = (mode == SHOWJOBS_PGIDS) ? 1 : jp->nprocs;
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308 jobno = jp - jobtab + 1;
309 curr = prev = 0;
310#if JOBS
311 if ((j = getcurjob(NULL)) != NULL) {
312 curr = j - jobtab + 1;
313 if ((j = getcurjob(j)) != NULL)
314 prev = j - jobtab + 1;
315 }
316#endif
99512ac4
PA
317 ps = jp->ps + jp->nprocs - 1;
318 if (jp->state == 0) {
319 strcpy(statestr, "Running");
320#if JOBS
321 } else if (jp->state == JOBSTOPPED) {
322 while (!WIFSTOPPED(ps->status) && ps > jp->ps)
323 ps--;
324 if (WIFSTOPPED(ps->status))
325 i = WSTOPSIG(ps->status);
326 else
327 i = -1;
328 if (i > 0 && i < sys_nsig && sys_siglist[i])
329 strcpy(statestr, sys_siglist[i]);
330 else
331 strcpy(statestr, "Suspended");
332#endif
333 } else if (WIFEXITED(ps->status)) {
334 if (WEXITSTATUS(ps->status) == 0)
335 strcpy(statestr, "Done");
336 else
337 fmtstr(statestr, 64, "Done(%d)",
338 WEXITSTATUS(ps->status));
339 } else {
340 i = WTERMSIG(ps->status);
341 if (i > 0 && i < sys_nsig && sys_siglist[i])
342 strcpy(statestr, sys_siglist[i]);
343 else
344 fmtstr(statestr, 64, "Signal %d", i);
345 if (WCOREDUMP(ps->status))
346 strcat(statestr, " (core dumped)");
347 }
348
984263bc 349 for (ps = jp->ps ; ; ps++) { /* for each process */
9d7989de 350 if (mode == SHOWJOBS_PIDS || mode == SHOWJOBS_PGIDS) {
99512ac4 351 out1fmt("%d\n", (int)ps->pid);
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352 goto skip;
353 }
99512ac4 354 if (mode != SHOWJOBS_VERBOSE && ps != jp->ps)
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355 goto skip;
356 if (jobno == curr && ps == jp->ps)
357 c = '+';
358 else if (jobno == prev && ps == jp->ps)
359 c = '-';
360 else
361 c = ' ';
362 if (ps == jp->ps)
363 fmtstr(s, 64, "[%d] %c ", jobno, c);
364 else
365 fmtstr(s, 64, " %c ", c);
366 out1str(s);
367 col = strlen(s);
9d7989de 368 if (mode == SHOWJOBS_VERBOSE) {
984263bc
MD
369 fmtstr(s, 64, "%d ", (int)ps->pid);
370 out1str(s);
371 col += strlen(s);
372 }
99512ac4
PA
373 if (ps == jp->ps) {
374 out1str(statestr);
375 col += strlen(statestr);
984263bc 376 }
984263bc
MD
377 do {
378 out1c(' ');
379 col++;
380 } while (col < 30);
99512ac4
PA
381 if (mode == SHOWJOBS_VERBOSE) {
382 out1str(ps->cmd);
383 out1c('\n');
384 } else
385 printjobcmd(jp);
984263bc
MD
386skip: if (--procno <= 0)
387 break;
388 }
389}
390
391/*
392 * Print a list of jobs. If "change" is nonzero, only print jobs whose
393 * statuses have changed since the last call to showjobs.
394 *
395 * If the shell is interrupted in the process of creating a job, the
396 * result may be a job structure containing zero processes. Such structures
397 * will be freed here.
398 */
399
400void
9d7989de 401showjobs(int change, int mode)
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MD
402{
403 int jobno;
404 struct job *jp;
405
406 TRACE(("showjobs(%d) called\n", change));
99512ac4 407 checkzombies();
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MD
408 for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) {
409 if (! jp->used)
410 continue;
411 if (jp->nprocs == 0) {
412 freejob(jp);
413 continue;
414 }
415 if (change && ! jp->changed)
416 continue;
99512ac4 417 showjob(jp, mode);
984263bc 418 jp->changed = 0;
99512ac4
PA
419 /* Hack: discard jobs for which $! has not been referenced
420 * in interactive mode when they terminate.
421 */
422 if (jp->state == JOBDONE && !jp->remembered &&
423 (iflag || jp != bgjob)) {
984263bc
MD
424 freejob(jp);
425 }
426 }
427}
428
429
430/*
431 * Mark a job structure as unused.
432 */
433
99512ac4 434static void
984263bc
MD
435freejob(struct job *jp)
436{
437 struct procstat *ps;
438 int i;
439
440 INTOFF;
99512ac4
PA
441 if (bgjob == jp)
442 bgjob = NULL;
984263bc
MD
443 for (i = jp->nprocs, ps = jp->ps ; --i >= 0 ; ps++) {
444 if (ps->cmd != nullstr)
445 ckfree(ps->cmd);
446 }
447 if (jp->ps != &jp->ps0)
448 ckfree(jp->ps);
449 jp->used = 0;
450#if JOBS
451 deljob(jp);
452#endif
453 INTON;
454}
455
456
457
458int
459waitcmd(int argc, char **argv)
460{
461 struct job *job;
462 int status, retval;
463 struct job *jp;
464
465 if (argc > 1) {
466 job = getjob(argv[1]);
467 } else {
468 job = NULL;
469 }
470
471 /*
472 * Loop until a process is terminated or stopped, or a SIGINT is
473 * received.
474 */
475
476 in_waitcmd++;
477 do {
478 if (job != NULL) {
479 if (job->state) {
480 status = job->ps[job->nprocs - 1].status;
481 if (WIFEXITED(status))
482 retval = WEXITSTATUS(status);
483#if JOBS
484 else if (WIFSTOPPED(status))
485 retval = WSTOPSIG(status) + 128;
486#endif
487 else
488 retval = WTERMSIG(status) + 128;
99512ac4 489 if (! iflag || ! job->changed)
984263bc 490 freejob(job);
99512ac4
PA
491 else {
492 job->remembered = 0;
493 if (job == bgjob)
494 bgjob = NULL;
495 }
984263bc
MD
496 in_waitcmd--;
497 return retval;
498 }
499 } else {
99512ac4
PA
500 for (jp = jobtab ; jp < jobtab + njobs; jp++)
501 if (jp->used && jp->state == JOBDONE) {
502 if (! iflag || ! jp->changed)
503 freejob(jp);
504 else {
505 jp->remembered = 0;
506 if (jp == bgjob)
507 bgjob = NULL;
508 }
509 }
984263bc
MD
510 for (jp = jobtab ; ; jp++) {
511 if (jp >= jobtab + njobs) { /* no running procs */
512 in_waitcmd--;
513 return 0;
514 }
515 if (jp->used && jp->state == 0)
516 break;
517 }
518 }
2038fb68 519 } while (dowait(1, NULL) != -1);
984263bc
MD
520 in_waitcmd--;
521
522 return 0;
523}
524
525
526
527int
528jobidcmd(int argc __unused, char **argv)
529{
530 struct job *jp;
531 int i;
532
533 jp = getjob(argv[1]);
534 for (i = 0 ; i < jp->nprocs ; ) {
535 out1fmt("%d", (int)jp->ps[i].pid);
536 out1c(++i < jp->nprocs? ' ' : '\n');
537 }
538 return 0;
539}
540
541
542
543/*
544 * Convert a job name to a job structure.
545 */
546
99512ac4 547static struct job *
984263bc
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548getjob(char *name)
549{
550 int jobno;
551 struct job *found, *jp;
552 pid_t pid;
553 int i;
554
555 if (name == NULL) {
556#if JOBS
557currentjob: if ((jp = getcurjob(NULL)) == NULL)
558 error("No current job");
559 return (jp);
560#else
561 error("No current job");
562#endif
563 } else if (name[0] == '%') {
564 if (is_digit(name[1])) {
565 jobno = number(name + 1);
566 if (jobno > 0 && jobno <= njobs
567 && jobtab[jobno - 1].used != 0)
568 return &jobtab[jobno - 1];
569#if JOBS
570 } else if (name[1] == '%' && name[2] == '\0') {
571 goto currentjob;
572 } else if (name[1] == '+' && name[2] == '\0') {
573 goto currentjob;
574 } else if (name[1] == '-' && name[2] == '\0') {
575 if ((jp = getcurjob(NULL)) == NULL ||
576 (jp = getcurjob(jp)) == NULL)
577 error("No previous job");
578 return (jp);
579#endif
580 } else if (name[1] == '?') {
581 found = NULL;
582 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
583 if (jp->used && jp->nprocs > 0
584 && strstr(jp->ps[0].cmd, name + 2) != NULL) {
585 if (found)
586 error("%s: ambiguous", name);
587 found = jp;
588 }
589 }
590 if (found != NULL)
591 return (found);
592 } else {
593 found = NULL;
594 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
595 if (jp->used && jp->nprocs > 0
596 && prefix(name + 1, jp->ps[0].cmd)) {
597 if (found)
598 error("%s: ambiguous", name);
599 found = jp;
600 }
601 }
602 if (found)
603 return found;
604 }
605 } else if (is_number(name)) {
606 pid = (pid_t)number(name);
607 for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
608 if (jp->used && jp->nprocs > 0
609 && jp->ps[jp->nprocs - 1].pid == pid)
610 return jp;
611 }
612 }
613 error("No such job: %s", name);
614 /*NOTREACHED*/
615 return NULL;
616}
617
618
99512ac4
PA
619pid_t
620getjobpgrp(char *name)
621{
622 struct job *jp;
623
624 jp = getjob(name);
625 return -jp->ps[0].pid;
626}
984263bc
MD
627
628/*
629 * Return a new job structure,
630 */
631
632struct job *
633makejob(union node *node __unused, int nprocs)
634{
635 int i;
636 struct job *jp;
637
638 for (i = njobs, jp = jobtab ; ; jp++) {
639 if (--i < 0) {
640 INTOFF;
641 if (njobs == 0) {
642 jobtab = ckmalloc(4 * sizeof jobtab[0]);
643#if JOBS
644 jobmru = NULL;
645#endif
646 } else {
647 jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
648 memcpy(jp, jobtab, njobs * sizeof jp[0]);
649#if JOBS
650 /* Relocate `next' pointers and list head */
651 if (jobmru != NULL)
652 jobmru = &jp[jobmru - jobtab];
653 for (i = 0; i < njobs; i++)
654 if (jp[i].next != NULL)
655 jp[i].next = &jp[jp[i].next -
656 jobtab];
657#endif
99512ac4
PA
658 if (bgjob != NULL)
659 bgjob = &jp[bgjob - jobtab];
984263bc
MD
660 /* Relocate `ps' pointers */
661 for (i = 0; i < njobs; i++)
662 if (jp[i].ps == &jobtab[i].ps0)
663 jp[i].ps = &jp[i].ps0;
664 ckfree(jobtab);
665 jobtab = jp;
666 }
667 jp = jobtab + njobs;
668 for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0);
669 INTON;
670 break;
671 }
672 if (jp->used == 0)
673 break;
674 }
675 INTOFF;
676 jp->state = 0;
677 jp->used = 1;
678 jp->changed = 0;
679 jp->nprocs = 0;
680 jp->foreground = 0;
99512ac4 681 jp->remembered = 0;
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MD
682#if JOBS
683 jp->jobctl = jobctl;
684 jp->next = NULL;
685#endif
686 if (nprocs > 1) {
687 jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
688 } else {
689 jp->ps = &jp->ps0;
690 }
691 INTON;
99512ac4 692 TRACE(("makejob(%p, %d) returns %%%td\n", (void *)node, nprocs,
984263bc
MD
693 jp - jobtab + 1));
694 return jp;
695}
696
697#if JOBS
99512ac4 698static void
984263bc
MD
699setcurjob(struct job *cj)
700{
701 struct job *jp, *prev;
702
703 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
704 if (jp == cj) {
705 if (prev != NULL)
706 prev->next = jp->next;
707 else
708 jobmru = jp->next;
709 jp->next = jobmru;
710 jobmru = cj;
711 return;
712 }
713 }
714 cj->next = jobmru;
715 jobmru = cj;
716}
717
99512ac4 718static void
984263bc
MD
719deljob(struct job *j)
720{
721 struct job *jp, *prev;
722
723 for (prev = NULL, jp = jobmru; jp != NULL; prev = jp, jp = jp->next) {
724 if (jp == j) {
725 if (prev != NULL)
726 prev->next = jp->next;
727 else
728 jobmru = jp->next;
729 return;
730 }
731 }
732}
733
734/*
735 * Return the most recently used job that isn't `nj', and preferably one
736 * that is stopped.
737 */
99512ac4 738static struct job *
984263bc
MD
739getcurjob(struct job *nj)
740{
741 struct job *jp;
742
743 /* Try to find a stopped one.. */
744 for (jp = jobmru; jp != NULL; jp = jp->next)
745 if (jp->used && jp != nj && jp->state == JOBSTOPPED)
746 return (jp);
747 /* Otherwise the most recently used job that isn't `nj' */
748 for (jp = jobmru; jp != NULL; jp = jp->next)
749 if (jp->used && jp != nj)
750 return (jp);
751
752 return (NULL);
753}
754
755#endif
756
757/*
758 * Fork of a subshell. If we are doing job control, give the subshell its
759 * own process group. Jp is a job structure that the job is to be added to.
760 * N is the command that will be evaluated by the child. Both jp and n may
761 * be NULL. The mode parameter can be one of the following:
762 * FORK_FG - Fork off a foreground process.
763 * FORK_BG - Fork off a background process.
764 * FORK_NOJOB - Like FORK_FG, but don't give the process its own
765 * process group even if job control is on.
766 *
767 * When job control is turned off, background processes have their standard
768 * input redirected to /dev/null (except for the second and later processes
769 * in a pipeline).
770 */
771
772pid_t
773forkshell(struct job *jp, union node *n, int mode)
774{
775 pid_t pid;
776 pid_t pgrp;
777
99512ac4 778 TRACE(("forkshell(%%%td, %p, %d) called\n", jp - jobtab, (void *)n,
984263bc
MD
779 mode));
780 INTOFF;
99512ac4
PA
781 if (mode == FORK_BG && (jp == NULL || jp->nprocs == 0))
782 checkzombies();
984263bc
MD
783 flushall();
784 pid = fork();
785 if (pid == -1) {
786 TRACE(("Fork failed, errno=%d\n", errno));
787 INTON;
788 error("Cannot fork: %s", strerror(errno));
789 }
790 if (pid == 0) {
791 struct job *p;
792 int wasroot;
793 int i;
794
795 TRACE(("Child shell %d\n", (int)getpid()));
796 wasroot = rootshell;
797 rootshell = 0;
99512ac4 798 handler = &main_handler;
984263bc
MD
799 closescript();
800 INTON;
32931063 801 forcelocal = 0;
984263bc
MD
802 clear_traps();
803#if JOBS
804 jobctl = 0; /* do job control only in root shell */
805 if (wasroot && mode != FORK_NOJOB && mflag) {
806 if (jp == NULL || jp->nprocs == 0)
807 pgrp = getpid();
808 else
809 pgrp = jp->ps[0].pid;
810 if (setpgid(0, pgrp) == 0 && mode == FORK_FG) {
811 /*** this causes superfluous TIOCSPGRPS ***/
812 if (tcsetpgrp(ttyfd, pgrp) < 0)
813 error("tcsetpgrp failed, errno=%d", errno);
814 }
815 setsignal(SIGTSTP);
816 setsignal(SIGTTOU);
817 } else if (mode == FORK_BG) {
818 ignoresig(SIGINT);
819 ignoresig(SIGQUIT);
820 if ((jp == NULL || jp->nprocs == 0) &&
821 ! fd0_redirected_p ()) {
822 close(0);
823 if (open(_PATH_DEVNULL, O_RDONLY) != 0)
f893ef22 824 error("cannot open %s: %s",
984263bc
MD
825 _PATH_DEVNULL, strerror(errno));
826 }
827 }
828#else
829 if (mode == FORK_BG) {
830 ignoresig(SIGINT);
831 ignoresig(SIGQUIT);
832 if ((jp == NULL || jp->nprocs == 0) &&
833 ! fd0_redirected_p ()) {
834 close(0);
835 if (open(_PATH_DEVNULL, O_RDONLY) != 0)
f893ef22 836 error("cannot open %s: %s",
984263bc
MD
837 _PATH_DEVNULL, strerror(errno));
838 }
839 }
840#endif
841 INTOFF;
842 for (i = njobs, p = jobtab ; --i >= 0 ; p++)
843 if (p->used)
844 freejob(p);
845 INTON;
846 if (wasroot && iflag) {
847 setsignal(SIGINT);
848 setsignal(SIGQUIT);
849 setsignal(SIGTERM);
850 }
851 return pid;
852 }
853 if (rootshell && mode != FORK_NOJOB && mflag) {
854 if (jp == NULL || jp->nprocs == 0)
855 pgrp = pid;
856 else
857 pgrp = jp->ps[0].pid;
858 setpgid(pid, pgrp);
859 }
99512ac4
PA
860 if (mode == FORK_BG) {
861 if (bgjob != NULL && bgjob->state == JOBDONE &&
862 !bgjob->remembered && !iflag)
863 freejob(bgjob);
984263bc 864 backgndpid = pid; /* set $! */
99512ac4
PA
865 bgjob = jp;
866 }
984263bc
MD
867 if (jp) {
868 struct procstat *ps = &jp->ps[jp->nprocs++];
869 ps->pid = pid;
870 ps->status = -1;
871 ps->cmd = nullstr;
872 if (iflag && rootshell && n)
873 ps->cmd = commandtext(n);
874 jp->foreground = mode == FORK_FG;
875#if JOBS
876 setcurjob(jp);
877#endif
878 }
879 INTON;
880 TRACE(("In parent shell: child = %d\n", (int)pid));
881 return pid;
882}
883
884
885
886/*
887 * Wait for job to finish.
888 *
889 * Under job control we have the problem that while a child process is
890 * running interrupts generated by the user are sent to the child but not
891 * to the shell. This means that an infinite loop started by an inter-
892 * active user may be hard to kill. With job control turned off, an
893 * interactive user may place an interactive program inside a loop. If
894 * the interactive program catches interrupts, the user doesn't want
895 * these interrupts to also abort the loop. The approach we take here
896 * is to have the shell ignore interrupt signals while waiting for a
897 * foreground process to terminate, and then send itself an interrupt
898 * signal if the child process was terminated by an interrupt signal.
899 * Unfortunately, some programs want to do a bit of cleanup and then
900 * exit on interrupt; unless these processes terminate themselves by
901 * sending a signal to themselves (instead of calling exit) they will
902 * confuse this approach.
903 */
904
905int
906waitforjob(struct job *jp, int *origstatus)
907{
908#if JOBS
909 pid_t mypgrp = getpgrp();
99512ac4 910 int propagate_int = jp->jobctl && jp->foreground;
984263bc
MD
911#endif
912 int status;
913 int st;
914
915 INTOFF;
99512ac4 916 TRACE(("waitforjob(%%%td) called\n", jp - jobtab + 1));
984263bc
MD
917 while (jp->state == 0)
918 if (dowait(1, jp) == -1)
919 dotrap();
920#if JOBS
921 if (jp->jobctl) {
922 if (tcsetpgrp(ttyfd, mypgrp) < 0)
923 error("tcsetpgrp failed, errno=%d\n", errno);
924 }
925 if (jp->state == JOBSTOPPED)
926 setcurjob(jp);
927#endif
928 status = jp->ps[jp->nprocs - 1].status;
929 if (origstatus != NULL)
930 *origstatus = status;
931 /* convert to 8 bits */
932 if (WIFEXITED(status))
933 st = WEXITSTATUS(status);
934#if JOBS
935 else if (WIFSTOPPED(status))
936 st = WSTOPSIG(status) + 128;
937#endif
938 else
939 st = WTERMSIG(status) + 128;
940 if (! JOBS || jp->state == JOBDONE)
941 freejob(jp);
942 if (int_pending()) {
99512ac4 943 if (!WIFSIGNALED(status) || WTERMSIG(status) != SIGINT)
984263bc
MD
944 CLEAR_PENDING_INT;
945 }
99512ac4
PA
946#if JOBS
947 else if (rootshell && iflag && propagate_int &&
948 WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
949 kill(getpid(), SIGINT);
950#endif
984263bc
MD
951 INTON;
952 return st;
953}
954
955
956
957/*
958 * Wait for a process to terminate.
959 */
960
99512ac4 961static pid_t
984263bc
MD
962dowait(int block, struct job *job)
963{
964 pid_t pid;
965 int status;
966 struct procstat *sp;
967 struct job *jp;
968 struct job *thisjob;
969 int done;
970 int stopped;
971 int sig;
99512ac4 972 int coredump;
984263bc
MD
973
974 in_dowait++;
975 TRACE(("dowait(%d) called\n", block));
976 do {
977 pid = waitproc(block, &status);
978 TRACE(("wait returns %d, status=%d\n", (int)pid, status));
979 } while ((pid == -1 && errno == EINTR && breakwaitcmd == 0) ||
fc88d1a0 980 (pid > 0 && WIFSTOPPED(status) && !iflag));
984263bc 981 in_dowait--;
fc88d1a0
PA
982 if (pid == -1 && errno == ECHILD && job != NULL)
983 job->state = JOBDONE;
984263bc
MD
984 if (breakwaitcmd != 0) {
985 breakwaitcmd = 0;
7c9c5302
MD
986 /*
987 * Do not early terminate if the pid is positive, else the
988 * job will not be properly recorded.
989 */
990 if (pid <= 0)
991 return -1;
984263bc
MD
992 }
993 if (pid <= 0)
994 return pid;
995 INTOFF;
996 thisjob = NULL;
997 for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
99512ac4 998 if (jp->used && jp->nprocs > 0) {
984263bc
MD
999 done = 1;
1000 stopped = 1;
1001 for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
1002 if (sp->pid == -1)
1003 continue;
1004 if (sp->pid == pid) {
1005 TRACE(("Changing status of proc %d from 0x%x to 0x%x\n",
1006 (int)pid, sp->status,
1007 status));
1008 sp->status = status;
1009 thisjob = jp;
1010 }
1011 if (sp->status == -1)
1012 stopped = 0;
1013 else if (WIFSTOPPED(sp->status))
1014 done = 0;
1015 }
1016 if (stopped) { /* stopped or done */
1017 int state = done? JOBDONE : JOBSTOPPED;
1018 if (jp->state != state) {
99512ac4 1019 TRACE(("Job %td: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
984263bc 1020 jp->state = state;
99512ac4
PA
1021 if (jp != job) {
1022 if (done && !jp->remembered &&
1023 !iflag && jp != bgjob)
1024 freejob(jp);
984263bc 1025#if JOBS
99512ac4
PA
1026 else if (done)
1027 deljob(jp);
984263bc 1028#endif
99512ac4 1029 }
984263bc
MD
1030 }
1031 }
1032 }
1033 }
1034 INTON;
99512ac4
PA
1035 if (!thisjob || thisjob->state == 0)
1036 ;
1037 else if ((!rootshell || !iflag || thisjob == job) &&
1038 thisjob->foreground && thisjob->state != JOBSTOPPED) {
1039 sig = 0;
1040 coredump = 0;
1041 for (sp = thisjob->ps; sp < thisjob->ps + thisjob->nprocs; sp++)
1042 if (WIFSIGNALED(sp->status)) {
1043 sig = WTERMSIG(sp->status);
1044 coredump = WCOREDUMP(sp->status);
1045 }
1046 if (sig > 0 && sig != SIGINT && sig != SIGPIPE) {
1047 if (sig < sys_nsig && sys_siglist[sig])
1048 out2str(sys_siglist[sig]);
984263bc 1049 else
99512ac4
PA
1050 outfmt(out2, "Signal %d", sig);
1051 if (coredump)
1052 out2str(" (core dumped)");
1053 out2c('\n');
1054 flushout(out2);
984263bc
MD
1055 }
1056 } else {
fc88d1a0 1057 TRACE(("Not printing status, rootshell=%d, job=%p\n", rootshell, job));
99512ac4 1058 thisjob->changed = 1;
984263bc
MD
1059 }
1060 return pid;
1061}
1062
1063
1064
1065/*
1066 * Do a wait system call. If job control is compiled in, we accept
1067 * stopped processes. If block is zero, we return a value of zero
1068 * rather than blocking.
1069 */
99512ac4 1070static pid_t
984263bc
MD
1071waitproc(int block, int *status)
1072{
1073 int flags;
1074
1075#if JOBS
1076 flags = WUNTRACED;
1077#else
1078 flags = 0;
1079#endif
1080 if (block == 0)
1081 flags |= WNOHANG;
2038fb68 1082 return wait3(status, flags, NULL);
984263bc
MD
1083}
1084
1085/*
1086 * return 1 if there are stopped jobs, otherwise 0
1087 */
1088int job_warning = 0;
1089int
1090stoppedjobs(void)
1091{
1092 int jobno;
1093 struct job *jp;
1094
1095 if (job_warning)
1096 return (0);
1097 for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) {
1098 if (jp->used == 0)
1099 continue;
1100 if (jp->state == JOBSTOPPED) {
99512ac4 1101 out2fmt_flush("You have stopped jobs.\n");
984263bc
MD
1102 job_warning = 2;
1103 return (1);
1104 }
1105 }
1106
1107 return (0);
1108}
1109
99512ac4
PA
1110
1111static void
1112checkzombies(void)
1113{
1114 while (njobs > 0 && dowait(0, NULL) > 0)
1115 ;
1116}
1117
1118
1119int
1120backgndpidset(void)
1121{
1122 return backgndpid != -1;
1123}
1124
1125
1126pid_t
1127backgndpidval(void)
1128{
32931063 1129 if (bgjob != NULL && !forcelocal)
99512ac4
PA
1130 bgjob->remembered = 1;
1131 return backgndpid;
1132}
1133
984263bc
MD
1134/*
1135 * Return a string identifying a command (to be printed by the
1136 * jobs command.
1137 */
1138
99512ac4
PA
1139static char *cmdnextc;
1140static int cmdnleft;
984263bc
MD
1141#define MAXCMDTEXT 200
1142
1143char *
1144commandtext(union node *n)
1145{
1146 char *name;
1147
1148 cmdnextc = name = ckmalloc(MAXCMDTEXT);
1149 cmdnleft = MAXCMDTEXT - 4;
1150 cmdtxt(n);
1151 *cmdnextc = '\0';
1152 return name;
1153}
1154
1155
99512ac4 1156static void
984263bc
MD
1157cmdtxt(union node *n)
1158{
1159 union node *np;
1160 struct nodelist *lp;
492efe05 1161 const char *p;
984263bc
MD
1162 int i;
1163 char s[2];
1164
1165 if (n == NULL)
1166 return;
1167 switch (n->type) {
1168 case NSEMI:
1169 cmdtxt(n->nbinary.ch1);
1170 cmdputs("; ");
1171 cmdtxt(n->nbinary.ch2);
1172 break;
1173 case NAND:
1174 cmdtxt(n->nbinary.ch1);
1175 cmdputs(" && ");
1176 cmdtxt(n->nbinary.ch2);
1177 break;
1178 case NOR:
1179 cmdtxt(n->nbinary.ch1);
1180 cmdputs(" || ");
1181 cmdtxt(n->nbinary.ch2);
1182 break;
1183 case NPIPE:
1184 for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
1185 cmdtxt(lp->n);
1186 if (lp->next)
1187 cmdputs(" | ");
1188 }
1189 break;
1190 case NSUBSHELL:
1191 cmdputs("(");
1192 cmdtxt(n->nredir.n);
1193 cmdputs(")");
1194 break;
1195 case NREDIR:
1196 case NBACKGND:
1197 cmdtxt(n->nredir.n);
1198 break;
1199 case NIF:
1200 cmdputs("if ");
1201 cmdtxt(n->nif.test);
1202 cmdputs("; then ");
1203 cmdtxt(n->nif.ifpart);
1204 cmdputs("...");
1205 break;
1206 case NWHILE:
1207 cmdputs("while ");
1208 goto until;
1209 case NUNTIL:
1210 cmdputs("until ");
1211until:
1212 cmdtxt(n->nbinary.ch1);
1213 cmdputs("; do ");
1214 cmdtxt(n->nbinary.ch2);
1215 cmdputs("; done");
1216 break;
1217 case NFOR:
1218 cmdputs("for ");
1219 cmdputs(n->nfor.var);
1220 cmdputs(" in ...");
1221 break;
1222 case NCASE:
1223 cmdputs("case ");
1224 cmdputs(n->ncase.expr->narg.text);
1225 cmdputs(" in ...");
1226 break;
1227 case NDEFUN:
1228 cmdputs(n->narg.text);
1229 cmdputs("() ...");
1230 break;
1231 case NCMD:
1232 for (np = n->ncmd.args ; np ; np = np->narg.next) {
1233 cmdtxt(np);
1234 if (np->narg.next)
1235 cmdputs(" ");
1236 }
1237 for (np = n->ncmd.redirect ; np ; np = np->nfile.next) {
1238 cmdputs(" ");
1239 cmdtxt(np);
1240 }
1241 break;
1242 case NARG:
1243 cmdputs(n->narg.text);
1244 break;
1245 case NTO:
1246 p = ">"; i = 1; goto redir;
1247 case NAPPEND:
1248 p = ">>"; i = 1; goto redir;
1249 case NTOFD:
1250 p = ">&"; i = 1; goto redir;
1251 case NCLOBBER:
1252 p = ">|"; i = 1; goto redir;
1253 case NFROM:
1254 p = "<"; i = 0; goto redir;
1255 case NFROMTO:
1256 p = "<>"; i = 0; goto redir;
1257 case NFROMFD:
1258 p = "<&"; i = 0; goto redir;
1259redir:
1260 if (n->nfile.fd != i) {
1261 s[0] = n->nfile.fd + '0';
1262 s[1] = '\0';
1263 cmdputs(s);
1264 }
1265 cmdputs(p);
1266 if (n->type == NTOFD || n->type == NFROMFD) {
1267 if (n->ndup.dupfd >= 0)
1268 s[0] = n->ndup.dupfd + '0';
1269 else
1270 s[0] = '-';
1271 s[1] = '\0';
1272 cmdputs(s);
1273 } else {
1274 cmdtxt(n->nfile.fname);
1275 }
1276 break;
1277 case NHERE:
1278 case NXHERE:
1279 cmdputs("<<...");
1280 break;
1281 default:
1282 cmdputs("???");
1283 break;
1284 }
1285}
1286
1287
1288
99512ac4 1289static void
492efe05 1290cmdputs(const char *s)
984263bc 1291{
492efe05
CP
1292 const char *p;
1293 char *q;
984263bc
MD
1294 char c;
1295 int subtype = 0;
1296
1297 if (cmdnleft <= 0)
1298 return;
1299 p = s;
1300 q = cmdnextc;
1301 while ((c = *p++) != '\0') {
1302 if (c == CTLESC)
1303 *q++ = *p++;
1304 else if (c == CTLVAR) {
1305 *q++ = '$';
1306 if (--cmdnleft > 0)
1307 *q++ = '{';
1308 subtype = *p++;
99512ac4
PA
1309 if ((subtype & VSTYPE) == VSLENGTH && --cmdnleft > 0)
1310 *q++ = '#';
984263bc 1311 } else if (c == '=' && subtype != 0) {
99512ac4
PA
1312 *q = "}-+?=##%%\0X"[(subtype & VSTYPE) - VSNORMAL];
1313 if (*q)
1314 q++;
1315 else
1316 cmdnleft++;
1317 if (((subtype & VSTYPE) == VSTRIMLEFTMAX ||
1318 (subtype & VSTYPE) == VSTRIMRIGHTMAX) &&
1319 --cmdnleft > 0)
1320 *q = q[-1], q++;
984263bc
MD
1321 subtype = 0;
1322 } else if (c == CTLENDVAR) {
1323 *q++ = '}';
99512ac4
PA
1324 } else if (c == CTLBACKQ || c == CTLBACKQ+CTLQUOTE) {
1325 cmdnleft -= 5;
1326 if (cmdnleft > 0) {
1327 *q++ = '$';
1328 *q++ = '(';
1329 *q++ = '.';
1330 *q++ = '.';
1331 *q++ = '.';
1332 *q++ = ')';
1333 }
1334 } else if (c == CTLARI) {
1335 cmdnleft -= 2;
1336 if (cmdnleft > 0) {
1337 *q++ = '$';
1338 *q++ = '(';
1339 *q++ = '(';
1340 }
1341 p++;
1342 } else if (c == CTLENDARI) {
1343 if (--cmdnleft > 0) {
1344 *q++ = ')';
1345 *q++ = ')';
1346 }
1347 } else if (c == CTLQUOTEMARK || c == CTLQUOTEEND)
1348 cmdnleft++; /* ignore */
984263bc
MD
1349 else
1350 *q++ = c;
1351 if (--cmdnleft <= 0) {
1352 *q++ = '.';
1353 *q++ = '.';
1354 *q++ = '.';
1355 break;
1356 }
1357 }
1358 cmdnextc = q;
1359}