jobs.c@ 1158

Last change on this file since 1158 was 809, checked in by bird, 18 years ago
Solaris + cleanup.
Property svn:eol-style set to `native`
File size: 31.4 KB

Line
1	/* $NetBSD: jobs.c,v 1.63 2005/06/01 15:41:19 lukem 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	#ifdef HAVE_SYS_CDEFS_H
36	#include <sys/cdefs.h>
37	#else
38	#define _PATH_DEVNULL "/dev/null"
39	#endif
40	#ifndef lint
41	#if 0
42	static char sccsid[] = "@(#)jobs.c 8.5 (Berkeley) 5/4/95";
43	#else
44	__RCSID("$NetBSD: jobs.c,v 1.63 2005/06/01 15:41:19 lukem Exp $");
45	#endif
46	#endif /* not lint */
47
48	#include <fcntl.h>
49	#ifdef __sun__
50	#define sys_siglist _sys_siglist
51	#endif
52	#include <signal.h>
53	#include <errno.h>
54	#include <unistd.h>
55	#include <stdlib.h>
56	#ifndef __sun__
57	#include <paths.h>
58	#endif
59	#include <sys/types.h>
60	#include <sys/param.h>
61	#if defined(BSD) \|\| defined(__sun__)
62	#include <sys/wait.h>
63	#include <sys/time.h>
64	#include <sys/resource.h>
65	#endif
66	#include <sys/ioctl.h>
67
68	#include "shell.h"
69	#if JOBS
70	#if OLD_TTY_DRIVER
71	#include "sgtty.h"
72	#else
73	#include <termios.h>
74	#endif
75	#undef CEOF /* syntax.h redefines this */
76	#endif
77	#include "redir.h"
78	#include "show.h"
79	#include "main.h"
80	#include "parser.h"
81	#include "nodes.h"
82	#include "jobs.h"
83	#include "options.h"
84	#include "trap.h"
85	#include "syntax.h"
86	#include "input.h"
87	#include "output.h"
88	#include "memalloc.h"
89	#include "error.h"
90	#include "mystring.h"
91
92
93	static struct job jobtab; / array of jobs */
94	static int njobs; /* size of array */
95	static int jobs_invalid; /* set in child */
96	MKINIT pid_t backgndpid = -1; /* pid of last background process */
97	#if JOBS
98	int initialpgrp; /* pgrp of shell on invocation */
99	static int curjob = -1; /* current job */
100	#endif
101	static int ttyfd = -1;
102
103	STATIC void restartjob(struct job *);
104	STATIC void freejob(struct job *);
105	STATIC struct job getjob(const char , int);
106	STATIC int dowait(int, struct job *);
107	STATIC int onsigchild(void);
108	STATIC int waitproc(int, struct job , int );
109	STATIC void cmdtxt(union node *);
110	STATIC void cmdlist(union node *, int);
111	STATIC void cmdputs(const char *);
112
113	#ifdef OLD_TTY_DRIVER
114	static pid_t tcgetpgrp(int fd);
115	static int tcsetpgrp(int fd, pid_t pgrp);
116
117	static pid_t
118	tcgetpgrp(int fd)
119	{
120	pid_t pgrp;
121	if (ioctl(fd, TIOCGPGRP, (char *)&pgrp) == -1)
122	return -1;
123	else
124	return pgrp;
125	}
126
127	static int
128	tcsetpgrp(int fd, pid_tpgrp)
129	{
130	return ioctl(fd, TIOCSPGRP, (char *)&pgrp);
131	}
132	#endif
133
134	/*
135	* Turn job control on and off.
136	*
137	* Note: This code assumes that the third arg to ioctl is a character
138	* pointer, which is true on Berkeley systems but not System V. Since
139	* System V doesn't have job control yet, this isn't a problem now.
140	*/
141
142	MKINIT int jobctl;
143
144	void
145	setjobctl(int on)
146	{
147	#ifdef OLD_TTY_DRIVER
148	int ldisc;
149	#endif
150
151	if (on == jobctl \|\| rootshell == 0)
152	return;
153	if (on) {
154	#if defined(FIOCLEX) \|\| defined(FD_CLOEXEC)
155	int err;
156	int i;
157	if (ttyfd != -1)
158	close(ttyfd);
159	if ((ttyfd = open("/dev/tty", O_RDWR)) == -1) {
160	for (i = 0; i < 3; i++) {
161	if (isatty(i) && (ttyfd = dup(i)) != -1)
162	break;
163	}
164	if (i == 3)
165	goto out;
166	}
167	/* Move to a high fd */
168	for (i = 10; i > 2; i--) {
169	if ((err = fcntl(ttyfd, F_DUPFD, (1 << i) - 1)) != -1)
170	break;
171	}
172	if (err != -1) {
173	close(ttyfd);
174	ttyfd = err;
175	}
176	#ifdef FIOCLEX
177	err = ioctl(ttyfd, FIOCLEX, 0);
178	#elif FD_CLOEXEC
179	err = fcntl(ttyfd, F_SETFD,
180	fcntl(ttyfd, F_GETFD, 0) \| FD_CLOEXEC);
181	#endif
182	if (err == -1) {
183	close(ttyfd);
184	ttyfd = -1;
185	goto out;
186	}
187	#else
188	out2str("sh: Need FIOCLEX or FD_CLOEXEC to support job control");
189	goto out;
190	#endif
191	do { /* while we are in the background */
192	if ((initialpgrp = tcgetpgrp(ttyfd)) < 0) {
193	out:
194	out2str("sh: can't access tty; job control turned off\n");
195	mflag = 0;
196	return;
197	}
198	if (initialpgrp == -1)
199	initialpgrp = getpgrp();
200	else if (initialpgrp != getpgrp()) {
201	killpg(0, SIGTTIN);
202	continue;
203	}
204	} while (0);
205
206	#ifdef OLD_TTY_DRIVER
207	if (ioctl(ttyfd, TIOCGETD, (char *)&ldisc) < 0
208	\|\| ldisc != NTTYDISC) {
209	out2str("sh: need new tty driver to run job control; job control turned off\n");
210	mflag = 0;
211	return;
212	}
213	#endif
214	setsignal(SIGTSTP, 0);
215	setsignal(SIGTTOU, 0);
216	setsignal(SIGTTIN, 0);
217	if (getpgid(0) != rootpid && setpgid(0, rootpid) == -1)
218	error("Cannot set process group (%s) at %d",
219	strerror(errno), __LINE__);
220	if (tcsetpgrp(ttyfd, rootpid) == -1)
221	error("Cannot set tty process group (%s) at %d",
222	strerror(errno), __LINE__);
223	} else { /* turning job control off */
224	if (getpgid(0) != initialpgrp && setpgid(0, initialpgrp) == -1)
225	error("Cannot set process group (%s) at %d",
226	strerror(errno), __LINE__);
227	if (tcsetpgrp(ttyfd, initialpgrp) == -1)
228	error("Cannot set tty process group (%s) at %d",
229	strerror(errno), __LINE__);
230	close(ttyfd);
231	ttyfd = -1;
232	setsignal(SIGTSTP, 0);
233	setsignal(SIGTTOU, 0);
234	setsignal(SIGTTIN, 0);
235	}
236	jobctl = on;
237	}
238
239
240	#ifdef mkinit
241	INCLUDE <stdlib.h>
242
243	SHELLPROC {
244	backgndpid = -1;
245	#if JOBS
246	jobctl = 0;
247	#endif
248	}
249
250	#endif
251
252
253
254	#if JOBS
255	int
256	fgcmd(int argc, char **argv)
257	{
258	struct job *jp;
259	int i;
260	int status;
261
262	nextopt("");
263	jp = getjob(*argptr, 0);
264	if (jp->jobctl == 0)
265	error("job not created under job control");
266	out1fmt("%s", jp->ps[0].cmd);
267	for (i = 1; i < jp->nprocs; i++)
268	out1fmt(" \| %s", jp->ps[i].cmd );
269	out1c('\n');
270	output_flushall();
271
272	for (i = 0; i < jp->nprocs; i++)
273	if (tcsetpgrp(ttyfd, jp->ps[i].pid) != -1)
274	break;
275
276	if (i >= jp->nprocs) {
277	error("Cannot set tty process group (%s) at %d",
278	strerror(errno), __LINE__);
279	}
280	restartjob(jp);
281	INTOFF;
282	status = waitforjob(jp);
283	INTON;
284	return status;
285	}
286
287	static void
288	set_curjob(struct job *jp, int mode)
289	{
290	struct job jp1, jp2;
291	int i, ji;
292
293	ji = jp - jobtab;
294
295	/* first remove from list */
296	if (ji == curjob)
297	curjob = jp->prev_job;
298	else {
299	for (i = 0; i < njobs; i++) {
300	if (jobtab[i].prev_job != ji)
301	continue;
302	jobtab[i].prev_job = jp->prev_job;
303	break;
304	}
305	}
306
307	/* Then re-insert in correct position */
308	switch (mode) {
309	case 0: /* job being deleted */
310	jp->prev_job = -1;
311	break;
312	case 1: /* newly created job or backgrounded job,
313	put after all stopped jobs. */
314	if (curjob != -1 && jobtab[curjob].state == JOBSTOPPED) {
315	for (jp1 = jobtab + curjob; ; jp1 = jp2) {
316	if (jp1->prev_job == -1)
317	break;
318	jp2 = jobtab + jp1->prev_job;
319	if (jp2->state != JOBSTOPPED)
320	break;
321	}
322	jp->prev_job = jp1->prev_job;
323	jp1->prev_job = ji;
324	break;
325	}
326	/* FALLTHROUGH */
327	case 2: /* newly stopped job - becomes curjob */
328	jp->prev_job = curjob;
329	curjob = ji;
330	break;
331	}
332	}
333
334	int
335	bgcmd(int argc, char **argv)
336	{
337	struct job *jp;
338	int i;
339
340	nextopt("");
341	do {
342	jp = getjob(*argptr, 0);
343	if (jp->jobctl == 0)
344	error("job not created under job control");
345	set_curjob(jp, 1);
346	out1fmt("[%ld] %s", (long)(jp - jobtab + 1), jp->ps[0].cmd);
347	for (i = 1; i < jp->nprocs; i++)
348	out1fmt(" \| %s", jp->ps[i].cmd );
349	out1c('\n');
350	output_flushall();
351	restartjob(jp);
352	} while (argptr && ++argptr);
353	return 0;
354	}
355
356
357	STATIC void
358	restartjob(struct job *jp)
359	{
360	struct procstat *ps;
361	int i;
362
363	if (jp->state == JOBDONE)
364	return;
365	INTOFF;
366	for (i = 0; i < jp->nprocs; i++)
367	if (killpg(jp->ps[i].pid, SIGCONT) != -1)
368	break;
369	if (i >= jp->nprocs)
370	error("Cannot continue job (%s)", strerror(errno));
371	for (ps = jp->ps, i = jp->nprocs ; --i >= 0 ; ps++) {
372	if (WIFSTOPPED(ps->status)) {
373	ps->status = -1;
374	jp->state = JOBRUNNING;
375	}
376	}
377	INTON;
378	}
379	#endif
380
381	static void
382	showjob(struct output out, struct job jp, int mode)
383	{
384	int procno;
385	int st;
386	struct procstat *ps;
387	int col;
388	char s[64];
389
390	#if JOBS
391	if (mode & SHOW_PGID) {
392	/* just output process (group) id of pipeline */
393	outfmt(out, "%ld\n", (long)jp->ps->pid);
394	return;
395	}
396	#endif
397
398	procno = jp->nprocs;
399	if (!procno)
400	return;
401
402	if (mode & SHOW_PID)
403	mode \|= SHOW_MULTILINE;
404
405	if ((procno > 1 && !(mode & SHOW_MULTILINE))
406	\|\| (mode & SHOW_SIGNALLED)) {
407	/* See if we have more than one status to report */
408	ps = jp->ps;
409	st = ps->status;
410	do {
411	int st1 = ps->status;
412	if (st1 != st)
413	/* yes - need multi-line output */
414	mode \|= SHOW_MULTILINE;
415	if (st1 == -1 \|\| !(mode & SHOW_SIGNALLED) \|\| WIFEXITED(st1))
416	continue;
417	if (WIFSTOPPED(st1) \|\| ((st1 = WTERMSIG(st1) & 0x7f)
418	&& st1 != SIGINT && st1 != SIGPIPE))
419	mode \|= SHOW_ISSIG;
420
421	} while (ps++, --procno);
422	procno = jp->nprocs;
423	}
424
425	if (mode & SHOW_SIGNALLED && !(mode & SHOW_ISSIG)) {
426	if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE)) {
427	TRACE(("showjob: freeing job %d\n", jp - jobtab + 1));
428	freejob(jp);
429	}
430	return;
431	}
432
433	for (ps = jp->ps; --procno >= 0; ps++) { /* for each process */
434	if (ps == jp->ps)
435	fmtstr(s, 16, "[%ld] %c ",
436	(long)(jp - jobtab + 1),
437	#if JOBS
438	jp == jobtab + curjob ? '+' :
439	curjob != -1 && jp == jobtab +
440	jobtab[curjob].prev_job ? '-' :
441	#endif
442	' ');
443	else
444	fmtstr(s, 16, " " );
445	col = strlen(s);
446	if (mode & SHOW_PID) {
447	fmtstr(s + col, 16, "%ld ", (long)ps->pid);
448	col += strlen(s + col);
449	}
450	if (ps->status == -1) {
451	scopy("Running", s + col);
452	} else if (WIFEXITED(ps->status)) {
453	st = WEXITSTATUS(ps->status);
454	if (st)
455	fmtstr(s + col, 16, "Done(%d)", st);
456	else
457	fmtstr(s + col, 16, "Done");
458	} else {
459	#if JOBS
460	if (WIFSTOPPED(ps->status))
461	st = WSTOPSIG(ps->status);
462	else /* WIFSIGNALED(ps->status) */
463	#endif
464	st = WTERMSIG(ps->status);
465	st &= 0x7f;
466	if (st < NSIG && sys_siglist[st])
467	scopyn(sys_siglist[st], s + col, 32);
468	else
469	fmtstr(s + col, 16, "Signal %d", st);
470	if (WCOREDUMP(ps->status)) {
471	col += strlen(s + col);
472	scopyn(" (core dumped)", s + col, 64 - col);
473	}
474	}
475	col += strlen(s + col);
476	outstr(s, out);
477	do {
478	outc(' ', out);
479	col++;
480	} while (col < 30);
481	outstr(ps->cmd, out);
482	if (mode & SHOW_MULTILINE) {
483	if (procno > 0) {
484	outc(' ', out);
485	outc('\|', out);
486	}
487	} else {
488	while (--procno >= 0)
489	outfmt(out, " \| %s", (++ps)->cmd );
490	}
491	outc('\n', out);
492	}
493	flushout(out);
494	jp->changed = 0;
495	if (jp->state == JOBDONE && !(mode & SHOW_NO_FREE))
496	freejob(jp);
497	}
498
499
500	int
501	jobscmd(int argc, char **argv)
502	{
503	int mode, m;
504	int sv = jobs_invalid;
505
506	jobs_invalid = 0;
507	mode = 0;
508	while ((m = nextopt("lp")))
509	if (m == 'l')
510	mode = SHOW_PID;
511	else
512	mode = SHOW_PGID;
513	if (*argptr)
514	do
515	showjob(out1, getjob(*argptr,0), mode);
516	while (*++argptr);
517	else
518	showjobs(out1, mode);
519	jobs_invalid = sv;
520	return 0;
521	}
522
523
524	/*
525	* Print a list of jobs. If "change" is nonzero, only print jobs whose
526	* statuses have changed since the last call to showjobs.
527	*
528	* If the shell is interrupted in the process of creating a job, the
529	* result may be a job structure containing zero processes. Such structures
530	* will be freed here.
531	*/
532
533	void
534	showjobs(struct output *out, int mode)
535	{
536	int jobno;
537	struct job *jp;
538	int silent = 0, gotpid;
539
540	TRACE(("showjobs(%x) called\n", mode));
541
542	/* If not even one one job changed, there is nothing to do */
543	gotpid = dowait(0, NULL);
544	while (dowait(0, NULL) > 0)
545	continue;
546	#ifdef JOBS
547	/*
548	* Check if we are not in our foreground group, and if not
549	* put us in it.
550	*/
551	if (mflag && gotpid != -1 && tcgetpgrp(ttyfd) != getpid()) {
552	if (tcsetpgrp(ttyfd, getpid()) == -1)
553	error("Cannot set tty process group (%s) at %d",
554	strerror(errno), __LINE__);
555	TRACE(("repaired tty process group\n"));
556	silent = 1;
557	}
558	#endif
559	if (jobs_invalid)
560	return;
561
562	for (jobno = 1, jp = jobtab ; jobno <= njobs ; jobno++, jp++) {
563	if (!jp->used)
564	continue;
565	if (jp->nprocs == 0) {
566	freejob(jp);
567	continue;
568	}
569	if ((mode & SHOW_CHANGED) && !jp->changed)
570	continue;
571	if (silent && jp->changed) {
572	jp->changed = 0;
573	continue;
574	}
575	showjob(out, jp, mode);
576	}
577	}
578
579	/*
580	* Mark a job structure as unused.
581	*/
582
583	STATIC void
584	freejob(struct job *jp)
585	{
586	INTOFF;
587	if (jp->ps != &jp->ps0) {
588	ckfree(jp->ps);
589	jp->ps = &jp->ps0;
590	}
591	jp->nprocs = 0;
592	jp->used = 0;
593	#if JOBS
594	set_curjob(jp, 0);
595	#endif
596	INTON;
597	}
598
599
600
601	int
602	waitcmd(int argc, char **argv)
603	{
604	struct job *job;
605	int status, retval;
606	struct job *jp;
607
608	nextopt("");
609
610	if (!*argptr) {
611	/* wait for all jobs */
612	jp = jobtab;
613	if (jobs_invalid)
614	return 0;
615	for (;;) {
616	if (jp >= jobtab + njobs) {
617	/* no running procs */
618	return 0;
619	}
620	if (!jp->used \|\| jp->state != JOBRUNNING) {
621	jp++;
622	continue;
623	}
624	if (dowait(1, (struct job *)NULL) == -1)
625	return 128 + SIGINT;
626	jp = jobtab;
627	}
628	}
629
630	retval = 127; /* XXXGCC: -Wuninitialized */
631	for (; *argptr; argptr++) {
632	job = getjob(*argptr, 1);
633	if (!job) {
634	retval = 127;
635	continue;
636	}
637	/* loop until process terminated or stopped */
638	while (job->state == JOBRUNNING) {
639	if (dowait(1, (struct job *)NULL) == -1)
640	return 128 + SIGINT;
641	}
642	status = job->ps[job->nprocs].status;
643	if (WIFEXITED(status))
644	retval = WEXITSTATUS(status);
645	#if JOBS
646	else if (WIFSTOPPED(status))
647	retval = WSTOPSIG(status) + 128;
648	#endif
649	else {
650	/* XXX: limits number of signals */
651	retval = WTERMSIG(status) + 128;
652	}
653	if (!iflag)
654	freejob(job);
655	}
656	return retval;
657	}
658
659
660
661	int
662	jobidcmd(int argc, char **argv)
663	{
664	struct job *jp;
665	int i;
666
667	nextopt("");
668	jp = getjob(*argptr, 0);
669	for (i = 0 ; i < jp->nprocs ; ) {
670	out1fmt("%ld", (long)jp->ps[i].pid);
671	out1c(++i < jp->nprocs ? ' ' : '\n');
672	}
673	return 0;
674	}
675
676	int
677	getjobpgrp(const char *name)
678	{
679	struct job *jp;
680
681	jp = getjob(name, 1);
682	if (jp == 0)
683	return 0;
684	return -jp->ps[0].pid;
685	}
686
687	/*
688	* Convert a job name to a job structure.
689	*/
690
691	STATIC struct job *
692	getjob(const char *name, int noerror)
693	{
694	int jobno = -1;
695	struct job *jp;
696	int pid;
697	int i;
698	const char *err_msg = "No such job: %s";
699
700	if (name == NULL) {
701	#if JOBS
702	jobno = curjob;
703	#endif
704	err_msg = "No current job";
705	} else if (name[0] == '%') {
706	if (is_number(name + 1)) {
707	jobno = number(name + 1) - 1;
708	} else if (!name[2]) {
709	switch (name[1]) {
710	#if JOBS
711	case 0:
712	case '+':
713	case '%':
714	jobno = curjob;
715	err_msg = "No current job";
716	break;
717	case '-':
718	jobno = curjob;
719	if (jobno != -1)
720	jobno = jobtab[jobno].prev_job;
721	err_msg = "No previous job";
722	break;
723	#endif
724	default:
725	goto check_pattern;
726	}
727	} else {
728	struct job *found;
729	check_pattern:
730	found = NULL;
731	for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
732	if (!jp->used \|\| jp->nprocs <= 0)
733	continue;
734	if ((name[1] == '?'
735	&& strstr(jp->ps[0].cmd, name + 2))
736	\|\| prefix(name + 1, jp->ps[0].cmd)) {
737	if (found) {
738	err_msg = "%s: ambiguous";
739	found = 0;
740	break;
741	}
742	found = jp;
743	}
744	}
745	if (found)
746	return found;
747	}
748
749	} else if (is_number(name)) {
750	pid = number(name);
751	for (jp = jobtab, i = njobs ; --i >= 0 ; jp++) {
752	if (jp->used && jp->nprocs > 0
753	&& jp->ps[jp->nprocs - 1].pid == pid)
754	return jp;
755	}
756	}
757
758	if (!jobs_invalid && jobno >= 0 && jobno < njobs) {
759	jp = jobtab + jobno;
760	if (jp->used)
761	return jp;
762	}
763	if (!noerror)
764	error(err_msg, name);
765	return 0;
766	}
767
768
769
770	/*
771	* Return a new job structure,
772	*/
773
774	struct job *
775	makejob(union node *node, int nprocs)
776	{
777	int i;
778	struct job *jp;
779
780	if (jobs_invalid) {
781	for (i = njobs, jp = jobtab ; --i >= 0 ; jp++) {
782	if (jp->used)
783	freejob(jp);
784	}
785	jobs_invalid = 0;
786	}
787
788	for (i = njobs, jp = jobtab ; ; jp++) {
789	if (--i < 0) {
790	INTOFF;
791	if (njobs == 0) {
792	jobtab = ckmalloc(4 * sizeof jobtab[0]);
793	} else {
794	jp = ckmalloc((njobs + 4) * sizeof jobtab[0]);
795	memcpy(jp, jobtab, njobs * sizeof jp[0]);
796	/* Relocate `ps' pointers */
797	for (i = 0; i < njobs; i++)
798	if (jp[i].ps == &jobtab[i].ps0)
799	jp[i].ps = &jp[i].ps0;
800	ckfree(jobtab);
801	jobtab = jp;
802	}
803	jp = jobtab + njobs;
804	for (i = 4 ; --i >= 0 ; jobtab[njobs++].used = 0);
805	INTON;
806	break;
807	}
808	if (jp->used == 0)
809	break;
810	}
811	INTOFF;
812	jp->state = JOBRUNNING;
813	jp->used = 1;
814	jp->changed = 0;
815	jp->nprocs = 0;
816	#if JOBS
817	jp->jobctl = jobctl;
818	set_curjob(jp, 1);
819	#endif
820	if (nprocs > 1) {
821	jp->ps = ckmalloc(nprocs * sizeof (struct procstat));
822	} else {
823	jp->ps = &jp->ps0;
824	}
825	INTON;
826	TRACE(("makejob(0x%lx, %d) returns %%%d\n", (long)node, nprocs,
827	jp - jobtab + 1));
828	return jp;
829	}
830
831
832	/*
833	* Fork off a subshell. If we are doing job control, give the subshell its
834	* own process group. Jp is a job structure that the job is to be added to.
835	* N is the command that will be evaluated by the child. Both jp and n may
836	* be NULL. The mode parameter can be one of the following:
837	* FORK_FG - Fork off a foreground process.
838	* FORK_BG - Fork off a background process.
839	* FORK_NOJOB - Like FORK_FG, but don't give the process its own
840	* process group even if job control is on.
841	*
842	* When job control is turned off, background processes have their standard
843	* input redirected to /dev/null (except for the second and later processes
844	* in a pipeline).
845	*/
846
847	int
848	forkshell(struct job jp, union node n, int mode)
849	{
850	int pid;
851
852	TRACE(("forkshell(%%%d, %p, %d) called\n", jp - jobtab, n, mode));
853	switch ((pid = fork())) {
854	case -1:
855	TRACE(("Fork failed, errno=%d\n", errno));
856	INTON;
857	error("Cannot fork");
858	break;
859	case 0:
860	forkchild(jp, n, mode, 0);
861	return 0;
862	default:
863	return forkparent(jp, n, mode, pid);
864	}
865	}
866
867	int
868	forkparent(struct job jp, union node n, int mode, pid_t pid)
869	{
870	int pgrp;
871
872	if (rootshell && mode != FORK_NOJOB && mflag) {
873	if (jp == NULL \|\| jp->nprocs == 0)
874	pgrp = pid;
875	else
876	pgrp = jp->ps[0].pid;
877	/* This can fail because we are doing it in the child also */
878	(void)setpgid(pid, pgrp);
879	}
880	if (mode == FORK_BG)
881	backgndpid = pid; /* set $! */
882	if (jp) {
883	struct procstat *ps = &jp->ps[jp->nprocs++];
884	ps->pid = pid;
885	ps->status = -1;
886	ps->cmd[0] = 0;
887	if (/* iflag && rootshell && */ n)
888	commandtext(ps, n);
889	}
890	TRACE(("In parent shell: child = %d\n", pid));
891	return pid;
892	}
893
894	void
895	forkchild(struct job jp, union node n, int mode, int vforked)
896	{
897	int wasroot;
898	int pgrp;
899	const char *devnull = _PATH_DEVNULL;
900	const char *nullerr = "Can't open %s";
901
902	wasroot = rootshell;
903	TRACE(("Child shell %d\n", getpid()));
904	if (!vforked)
905	rootshell = 0;
906
907	closescript(vforked);
908	clear_traps(vforked);
909	#if JOBS
910	if (!vforked)
911	jobctl = 0; /* do job control only in root shell */
912	if (wasroot && mode != FORK_NOJOB && mflag) {
913	if (jp == NULL \|\| jp->nprocs == 0)
914	pgrp = getpid();
915	else
916	pgrp = jp->ps[0].pid;
917	/* This can fail because we are doing it in the parent also */
918	(void)setpgid(0, pgrp);
919	if (mode == FORK_FG) {
920	if (tcsetpgrp(ttyfd, pgrp) == -1)
921	error("Cannot set tty process group (%s) at %d",
922	strerror(errno), __LINE__);
923	}
924	setsignal(SIGTSTP, vforked);
925	setsignal(SIGTTOU, vforked);
926	} else if (mode == FORK_BG) {
927	ignoresig(SIGINT, vforked);
928	ignoresig(SIGQUIT, vforked);
929	if ((jp == NULL \|\| jp->nprocs == 0) &&
930	! fd0_redirected_p ()) {
931	close(0);
932	if (open(devnull, O_RDONLY) != 0)
933	error(nullerr, devnull);
934	}
935	}
936	#else
937	if (mode == FORK_BG) {
938	ignoresig(SIGINT, vforked);
939	ignoresig(SIGQUIT, vforked);
940	if ((jp == NULL \|\| jp->nprocs == 0) &&
941	! fd0_redirected_p ()) {
942	close(0);
943	if (open(devnull, O_RDONLY) != 0)
944	error(nullerr, devnull);
945	}
946	}
947	#endif
948	if (wasroot && iflag) {
949	setsignal(SIGINT, vforked);
950	setsignal(SIGQUIT, vforked);
951	setsignal(SIGTERM, vforked);
952	}
953
954	if (!vforked)
955	jobs_invalid = 1;
956	}
957
958	/*
959	* Wait for job to finish.
960	*
961	* Under job control we have the problem that while a child process is
962	* running interrupts generated by the user are sent to the child but not
963	* to the shell. This means that an infinite loop started by an inter-
964	* active user may be hard to kill. With job control turned off, an
965	* interactive user may place an interactive program inside a loop. If
966	* the interactive program catches interrupts, the user doesn't want
967	* these interrupts to also abort the loop. The approach we take here
968	* is to have the shell ignore interrupt signals while waiting for a
969	* forground process to terminate, and then send itself an interrupt
970	* signal if the child process was terminated by an interrupt signal.
971	* Unfortunately, some programs want to do a bit of cleanup and then
972	* exit on interrupt; unless these processes terminate themselves by
973	* sending a signal to themselves (instead of calling exit) they will
974	* confuse this approach.
975	*/
976
977	int
978	waitforjob(struct job *jp)
979	{
980	#if JOBS
981	int mypgrp = getpgrp();
982	#endif
983	int status;
984	int st;
985
986	INTOFF;
987	TRACE(("waitforjob(%%%d) called\n", jp - jobtab + 1));
988	while (jp->state == JOBRUNNING) {
989	dowait(1, jp);
990	}
991	#if JOBS
992	if (jp->jobctl) {
993	if (tcsetpgrp(ttyfd, mypgrp) == -1)
994	error("Cannot set tty process group (%s) at %d",
995	strerror(errno), __LINE__);
996	}
997	if (jp->state == JOBSTOPPED && curjob != jp - jobtab)
998	set_curjob(jp, 2);
999	#endif
1000	status = jp->ps[jp->nprocs - 1].status;
1001	/* convert to 8 bits */
1002	if (WIFEXITED(status))
1003	st = WEXITSTATUS(status);
1004	#if JOBS
1005	else if (WIFSTOPPED(status))
1006	st = WSTOPSIG(status) + 128;
1007	#endif
1008	else
1009	st = WTERMSIG(status) + 128;
1010	TRACE(("waitforjob: job %d, nproc %d, status %x, st %x\n",
1011	jp - jobtab + 1, jp->nprocs, status, st ));
1012	#if JOBS
1013	if (jp->jobctl) {
1014	/*
1015	* This is truly gross.
1016	* If we're doing job control, then we did a TIOCSPGRP which
1017	* caused us (the shell) to no longer be in the controlling
1018	* session -- so we wouldn't have seen any ^C/SIGINT. So, we
1019	* intuit from the subprocess exit status whether a SIGINT
1020	* occurred, and if so interrupt ourselves. Yuck. - mycroft
1021	*/
1022	if (WIFSIGNALED(status) && WTERMSIG(status) == SIGINT)
1023	raise(SIGINT);
1024	}
1025	#endif
1026	if (! JOBS \|\| jp->state == JOBDONE)
1027	freejob(jp);
1028	INTON;
1029	return st;
1030	}
1031
1032
1033
1034	/*
1035	* Wait for a process to terminate.
1036	*/
1037
1038	STATIC int
1039	dowait(int block, struct job *job)
1040	{
1041	int pid;
1042	int status;
1043	struct procstat *sp;
1044	struct job *jp;
1045	struct job *thisjob;
1046	int done;
1047	int stopped;
1048	extern volatile char gotsig[];
1049
1050	TRACE(("dowait(%d) called\n", block));
1051	do {
1052	pid = waitproc(block, job, &status);
1053	TRACE(("wait returns pid %d, status %d\n", pid, status));
1054	} while (pid == -1 && errno == EINTR && gotsig[SIGINT - 1] == 0);
1055	if (pid <= 0)
1056	return pid;
1057	INTOFF;
1058	thisjob = NULL;
1059	for (jp = jobtab ; jp < jobtab + njobs ; jp++) {
1060	if (jp->used) {
1061	done = 1;
1062	stopped = 1;
1063	for (sp = jp->ps ; sp < jp->ps + jp->nprocs ; sp++) {
1064	if (sp->pid == -1)
1065	continue;
1066	if (sp->pid == pid) {
1067	TRACE(("Job %d: changing status of proc %d from 0x%x to 0x%x\n", jp - jobtab + 1, pid, sp->status, status));
1068	sp->status = status;
1069	thisjob = jp;
1070	}
1071	if (sp->status == -1)
1072	stopped = 0;
1073	else if (WIFSTOPPED(sp->status))
1074	done = 0;
1075	}
1076	if (stopped) { /* stopped or done */
1077	int state = done ? JOBDONE : JOBSTOPPED;
1078	if (jp->state != state) {
1079	TRACE(("Job %d: changing state from %d to %d\n", jp - jobtab + 1, jp->state, state));
1080	jp->state = state;
1081	#if JOBS
1082	if (done)
1083	set_curjob(jp, 0);
1084	#endif
1085	}
1086	}
1087	}
1088	}
1089
1090	if (thisjob && thisjob->state != JOBRUNNING) {
1091	int mode = 0;
1092	if (!rootshell \|\| !iflag)
1093	mode = SHOW_SIGNALLED;
1094	if (job == thisjob)
1095	mode = SHOW_SIGNALLED \| SHOW_NO_FREE;
1096	if (mode)
1097	showjob(out2, thisjob, mode);
1098	else {
1099	TRACE(("Not printing status, rootshell=%d, job=%p\n",
1100	rootshell, job));
1101	thisjob->changed = 1;
1102	}
1103	}
1104
1105	INTON;
1106	return pid;
1107	}
1108
1109
1110
1111	/*
1112	* Do a wait system call. If job control is compiled in, we accept
1113	* stopped processes. If block is zero, we return a value of zero
1114	* rather than blocking.
1115	*
1116	* System V doesn't have a non-blocking wait system call. It does
1117	* have a SIGCLD signal that is sent to a process when one of it's
1118	* children dies. The obvious way to use SIGCLD would be to install
1119	* a handler for SIGCLD which simply bumped a counter when a SIGCLD
1120	* was received, and have waitproc bump another counter when it got
1121	* the status of a process. Waitproc would then know that a wait
1122	* system call would not block if the two counters were different.
1123	* This approach doesn't work because if a process has children that
1124	* have not been waited for, System V will send it a SIGCLD when it
1125	* installs a signal handler for SIGCLD. What this means is that when
1126	* a child exits, the shell will be sent SIGCLD signals continuously
1127	* until is runs out of stack space, unless it does a wait call before
1128	* restoring the signal handler. The code below takes advantage of
1129	* this (mis)feature by installing a signal handler for SIGCLD and
1130	* then checking to see whether it was called. If there are any
1131	* children to be waited for, it will be.
1132	*
1133	* If neither SYSV nor BSD is defined, we don't implement nonblocking
1134	* waits at all. In this case, the user will not be informed when
1135	* a background process until the next time she runs a real program
1136	* (as opposed to running a builtin command or just typing return),
1137	* and the jobs command may give out of date information.
1138	*/
1139
1140	#ifdef SYSV
1141	STATIC int gotsigchild;
1142
1143	STATIC int onsigchild() {
1144	gotsigchild = 1;
1145	}
1146	#endif
1147
1148
1149	STATIC int
1150	waitproc(int block, struct job jp, int status)
1151	{
1152	#ifdef BSD
1153	int flags = 0;
1154
1155	#if JOBS
1156	if (jp != NULL && jp->jobctl)
1157	flags \|= WUNTRACED;
1158	#endif
1159	if (block == 0)
1160	flags \|= WNOHANG;
1161	return wait3(status, flags, (struct rusage *)NULL);
1162	#else
1163	#ifdef SYSV
1164	int (*save)();
1165
1166	if (block == 0) {
1167	gotsigchild = 0;
1168	save = signal(SIGCLD, onsigchild);
1169	signal(SIGCLD, save);
1170	if (gotsigchild == 0)
1171	return 0;
1172	}
1173	return wait(status);
1174	#else
1175	if (block == 0)
1176	return 0;
1177	return wait(status);
1178	#endif
1179	#endif
1180	}
1181
1182	/*
1183	* return 1 if there are stopped jobs, otherwise 0
1184	*/
1185	int job_warning = 0;
1186	int
1187	stoppedjobs(void)
1188	{
1189	int jobno;
1190	struct job *jp;
1191
1192	if (job_warning \|\| jobs_invalid)
1193	return (0);
1194	for (jobno = 1, jp = jobtab; jobno <= njobs; jobno++, jp++) {
1195	if (jp->used == 0)
1196	continue;
1197	if (jp->state == JOBSTOPPED) {
1198	out2str("You have stopped jobs.\n");
1199	job_warning = 2;
1200	return (1);
1201	}
1202	}
1203
1204	return (0);
1205	}
1206
1207	/*
1208	* Return a string identifying a command (to be printed by the
1209	* jobs command).
1210	*/
1211
1212	STATIC char *cmdnextc;
1213	STATIC int cmdnleft;
1214
1215	void
1216	commandtext(struct procstat ps, union node n)
1217	{
1218	int len;
1219
1220	cmdnextc = ps->cmd;
1221	if (iflag \|\| mflag \|\| sizeof ps->cmd < 100)
1222	len = sizeof(ps->cmd);
1223	else
1224	len = sizeof(ps->cmd) / 10;
1225	cmdnleft = len;
1226	cmdtxt(n);
1227	if (cmdnleft <= 0) {
1228	char *p = ps->cmd + len - 4;
1229	p[0] = '.';
1230	p[1] = '.';
1231	p[2] = '.';
1232	p[3] = 0;
1233	} else
1234	*cmdnextc = '\0';
1235	TRACE(("commandtext: ps->cmd %x, end %x, left %d\n\t\"%s\"\n",
1236	ps->cmd, cmdnextc, cmdnleft, ps->cmd));
1237	}
1238
1239
1240	STATIC void
1241	cmdtxt(union node *n)
1242	{
1243	union node *np;
1244	struct nodelist *lp;
1245	const char *p;
1246	int i;
1247	char s[2];
1248
1249	if (n == NULL \|\| cmdnleft <= 0)
1250	return;
1251	switch (n->type) {
1252	case NSEMI:
1253	cmdtxt(n->nbinary.ch1);
1254	cmdputs("; ");
1255	cmdtxt(n->nbinary.ch2);
1256	break;
1257	case NAND:
1258	cmdtxt(n->nbinary.ch1);
1259	cmdputs(" && ");
1260	cmdtxt(n->nbinary.ch2);
1261	break;
1262	case NOR:
1263	cmdtxt(n->nbinary.ch1);
1264	cmdputs(" \|\| ");
1265	cmdtxt(n->nbinary.ch2);
1266	break;
1267	case NPIPE:
1268	for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
1269	cmdtxt(lp->n);
1270	if (lp->next)
1271	cmdputs(" \| ");
1272	}
1273	break;
1274	case NSUBSHELL:
1275	cmdputs("(");
1276	cmdtxt(n->nredir.n);
1277	cmdputs(")");
1278	break;
1279	case NREDIR:
1280	case NBACKGND:
1281	cmdtxt(n->nredir.n);
1282	break;
1283	case NIF:
1284	cmdputs("if ");
1285	cmdtxt(n->nif.test);
1286	cmdputs("; then ");
1287	cmdtxt(n->nif.ifpart);
1288	if (n->nif.elsepart) {
1289	cmdputs("; else ");
1290	cmdtxt(n->nif.elsepart);
1291	}
1292	cmdputs("; fi");
1293	break;
1294	case NWHILE:
1295	cmdputs("while ");
1296	goto until;
1297	case NUNTIL:
1298	cmdputs("until ");
1299	until:
1300	cmdtxt(n->nbinary.ch1);
1301	cmdputs("; do ");
1302	cmdtxt(n->nbinary.ch2);
1303	cmdputs("; done");
1304	break;
1305	case NFOR:
1306	cmdputs("for ");
1307	cmdputs(n->nfor.var);
1308	cmdputs(" in ");
1309	cmdlist(n->nfor.args, 1);
1310	cmdputs("; do ");
1311	cmdtxt(n->nfor.body);
1312	cmdputs("; done");
1313	break;
1314	case NCASE:
1315	cmdputs("case ");
1316	cmdputs(n->ncase.expr->narg.text);
1317	cmdputs(" in ");
1318	for (np = n->ncase.cases; np; np = np->nclist.next) {
1319	cmdtxt(np->nclist.pattern);
1320	cmdputs(") ");
1321	cmdtxt(np->nclist.body);
1322	cmdputs(";; ");
1323	}
1324	cmdputs("esac");
1325	break;
1326	case NDEFUN:
1327	cmdputs(n->narg.text);
1328	cmdputs("() { ... }");
1329	break;
1330	case NCMD:
1331	cmdlist(n->ncmd.args, 1);
1332	cmdlist(n->ncmd.redirect, 0);
1333	break;
1334	case NARG:
1335	cmdputs(n->narg.text);
1336	break;
1337	case NTO:
1338	p = ">"; i = 1; goto redir;
1339	case NCLOBBER:
1340	p = ">\|"; i = 1; goto redir;
1341	case NAPPEND:
1342	p = ">>"; i = 1; goto redir;
1343	case NTOFD:
1344	p = ">&"; i = 1; goto redir;
1345	case NFROM:
1346	p = "<"; i = 0; goto redir;
1347	case NFROMFD:
1348	p = "<&"; i = 0; goto redir;
1349	case NFROMTO:
1350	p = "<>"; i = 0; goto redir;
1351	redir:
1352	if (n->nfile.fd != i) {
1353	s[0] = n->nfile.fd + '0';
1354	s[1] = '\0';
1355	cmdputs(s);
1356	}
1357	cmdputs(p);
1358	if (n->type == NTOFD \|\| n->type == NFROMFD) {
1359	s[0] = n->ndup.dupfd + '0';
1360	s[1] = '\0';
1361	cmdputs(s);
1362	} else {
1363	cmdtxt(n->nfile.fname);
1364	}
1365	break;
1366	case NHERE:
1367	case NXHERE:
1368	cmdputs("<<...");
1369	break;
1370	default:
1371	cmdputs("???");
1372	break;
1373	}
1374	}
1375
1376	STATIC void
1377	cmdlist(union node *np, int sep)
1378	{
1379	for (; np; np = np->narg.next) {
1380	if (!sep)
1381	cmdputs(" ");
1382	cmdtxt(np);
1383	if (sep && np->narg.next)
1384	cmdputs(" ");
1385	}
1386	}
1387
1388
1389	STATIC void
1390	cmdputs(const char *s)
1391	{
1392	const char p, str = 0;
1393	char c, cc[2] = " ";
1394	char *nextc;
1395	int nleft;
1396	int subtype = 0;
1397	int quoted = 0;
1398	static char vstype[16][4] = { "", "}", "-", "+", "?", "=",
1399	"#", "##", "%", "%%" };
1400
1401	p = s;
1402	nextc = cmdnextc;
1403	nleft = cmdnleft;
1404	while (nleft > 0 && (c = *p++) != 0) {
1405	switch (c) {
1406	case CTLESC:
1407	c = *p++;
1408	break;
1409	case CTLVAR:
1410	subtype = *p++;
1411	if ((subtype & VSTYPE) == VSLENGTH)
1412	str = "${#";
1413	else
1414	str = "${";
1415	if (!(subtype & VSQUOTE) != !(quoted & 1)) {
1416	quoted ^= 1;
1417	c = '"';
1418	} else
1419	c = *str++;
1420	break;
1421	case CTLENDVAR:
1422	if (quoted & 1) {
1423	c = '"';
1424	str = "}";
1425	} else
1426	c = '}';
1427	quoted >>= 1;
1428	subtype = 0;
1429	break;
1430	case CTLBACKQ:
1431	c = '$';
1432	str = "(...)";
1433	break;
1434	case CTLBACKQ+CTLQUOTE:
1435	c = '"';
1436	str = "$(...)\"";
1437	break;
1438	case CTLARI:
1439	c = '$';
1440	str = "((";
1441	break;
1442	case CTLENDARI:
1443	c = ')';
1444	str = ")";
1445	break;
1446	case CTLQUOTEMARK:
1447	quoted ^= 1;
1448	c = '"';
1449	break;
1450	case '=':
1451	if (subtype == 0)
1452	break;
1453	str = vstype[subtype & VSTYPE];
1454	if (subtype & VSNUL)
1455	c = ':';
1456	else
1457	c = *str++;
1458	if (c != '}')
1459	quoted <<= 1;
1460	break;
1461	case '\'':
1462	case '\\':
1463	case '"':
1464	case '$':
1465	/* These can only happen inside quotes */
1466	cc[0] = c;
1467	str = cc;
1468	c = '\\';
1469	break;
1470	default:
1471	break;
1472	}
1473	do {
1474	*nextc++ = c;
1475	} while (--nleft > 0 && str && (c = *str++));
1476	str = 0;
1477	}
1478	if ((quoted & 1) && nleft) {
1479	*nextc++ = '"';
1480	nleft--;
1481	}
1482	cmdnleft = nleft;
1483	cmdnextc = nextc;
1484	}

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source: kBuild/trunk/src/ash/jobs.c@ 1158

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