1/*	$OpenBSD: jobs.c,v 1.43 2015/09/10 22:48:58 nicm Exp $	*/
2
3/*-
4 * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011,
5 *		 2012, 2013, 2014, 2015, 2016, 2018
6 *	mirabilos <m@mirbsd.org>
7 *
8 * Provided that these terms and disclaimer and all copyright notices
9 * are retained or reproduced in an accompanying document, permission
10 * is granted to deal in this work without restriction, including un-
11 * limited rights to use, publicly perform, distribute, sell, modify,
12 * merge, give away, or sublicence.
13 *
14 * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
15 * the utmost extent permitted by applicable law, neither express nor
16 * implied; without malicious intent or gross negligence. In no event
17 * may a licensor, author or contributor be held liable for indirect,
18 * direct, other damage, loss, or other issues arising in any way out
19 * of dealing in the work, even if advised of the possibility of such
20 * damage or existence of a defect, except proven that it results out
21 * of said person's immediate fault when using the work as intended.
22 */
23
24#include "sh.h"
25
26__RCSID("$MirOS: src/bin/mksh/jobs.c,v 1.125 2018/01/05 20:08:34 tg Exp $");
27
28#if HAVE_KILLPG
29#define mksh_killpg		killpg
30#else
31/* cross fingers and hope kill is killpg-endowed */
32#define mksh_killpg(p,s)	kill(-(p), (s))
33#endif
34
35/* Order important! */
36#define PRUNNING	0
37#define PEXITED		1
38#define PSIGNALLED	2
39#define PSTOPPED	3
40
41typedef struct proc Proc;
42/* to take alignment into consideration */
43struct proc_dummy {
44	Proc *next;
45	pid_t pid;
46	int state;
47	int status;
48	char command[128];
49};
50/* real structure */
51struct proc {
52	/* next process in pipeline (if any) */
53	Proc *next;
54	/* process id of this Unix process in the job */
55	pid_t pid;
56	/* one of the four P… above */
57	int state;
58	/* wait status */
59	int status;
60	/* process command string from vistree */
61	char command[256 - (ALLOC_OVERHEAD +
62	    offsetof(struct proc_dummy, command[0]))];
63};
64
65/* Notify/print flag - j_print() argument */
66#define JP_SHORT	1	/* print signals processes were killed by */
67#define JP_MEDIUM	2	/* print [job-num] -/+ command */
68#define JP_LONG		3	/* print [job-num] -/+ pid command */
69#define JP_PGRP		4	/* print pgrp */
70
71/* put_job() flags */
72#define PJ_ON_FRONT	0	/* at very front */
73#define PJ_PAST_STOPPED	1	/* just past any stopped jobs */
74
75/* Job.flags values */
76#define JF_STARTED	0x001	/* set when all processes in job are started */
77#define JF_WAITING	0x002	/* set if j_waitj() is waiting on job */
78#define JF_W_ASYNCNOTIFY 0x004	/* set if waiting and async notification ok */
79#define JF_XXCOM	0x008	/* set for $(command) jobs */
80#define JF_FG		0x010	/* running in foreground (also has tty pgrp) */
81#define JF_SAVEDTTY	0x020	/* j->ttystat is valid */
82#define JF_CHANGED	0x040	/* process has changed state */
83#define JF_KNOWN	0x080	/* $! referenced */
84#define JF_ZOMBIE	0x100	/* known, unwaited process */
85#define JF_REMOVE	0x200	/* flagged for removal (j_jobs()/j_noityf()) */
86#define JF_USETTYMODE	0x400	/* tty mode saved if process exits normally */
87#define JF_SAVEDTTYPGRP	0x800	/* j->saved_ttypgrp is valid */
88
89typedef struct job Job;
90struct job {
91	Job *next;		/* next job in list */
92	Proc *proc_list;	/* process list */
93	Proc *last_proc;	/* last process in list */
94	struct timeval systime;	/* system time used by job */
95	struct timeval usrtime;	/* user time used by job */
96	pid_t pgrp;		/* process group of job */
97	pid_t ppid;		/* pid of process that forked job */
98	int job;		/* job number: %n */
99	int flags;		/* see JF_* */
100	volatile int state;	/* job state */
101	int status;		/* exit status of last process */
102	int age;		/* number of jobs started */
103	Coproc_id coproc_id;	/* 0 or id of coprocess output pipe */
104#ifndef MKSH_UNEMPLOYED
105	mksh_ttyst ttystat;	/* saved tty state for stopped jobs */
106	pid_t saved_ttypgrp;	/* saved tty process group for stopped jobs */
107#endif
108};
109
110/* Flags for j_waitj() */
111#define JW_NONE		0x00
112#define JW_INTERRUPT	0x01	/* ^C will stop the wait */
113#define JW_ASYNCNOTIFY	0x02	/* asynchronous notification during wait ok */
114#define JW_STOPPEDWAIT	0x04	/* wait even if job stopped */
115#define JW_PIPEST	0x08	/* want PIPESTATUS */
116
117/* Error codes for j_lookup() */
118#define JL_NOSUCH	0	/* no such job */
119#define JL_AMBIG	1	/* %foo or %?foo is ambiguous */
120#define JL_INVALID	2	/* non-pid, non-% job id */
121
122static const char * const lookup_msgs[] = {
123	"no such job",
124	"ambiguous",
125	"argument must be %job or process id"
126};
127
128static Job *job_list;		/* job list */
129static Job *last_job;
130static Job *async_job;
131static pid_t async_pid;
132
133static int nzombie;		/* # of zombies owned by this process */
134static int njobs;		/* # of jobs started */
135
136#ifndef CHILD_MAX
137#define CHILD_MAX	25
138#endif
139
140#ifndef MKSH_NOPROSPECTOFWORK
141/* held_sigchld is set if sigchld occurs before a job is completely started */
142static volatile sig_atomic_t held_sigchld;
143#endif
144
145#ifndef MKSH_UNEMPLOYED
146static struct shf	*shl_j;
147static bool		ttypgrp_ok;	/* set if can use tty pgrps */
148static pid_t		restore_ttypgrp = -1;
149static int const	tt_sigs[] = { SIGTSTP, SIGTTIN, SIGTTOU };
150#endif
151
152static void		j_set_async(Job *);
153static void		j_startjob(Job *);
154static int		j_waitj(Job *, int, const char *);
155static void		j_sigchld(int);
156static void		j_print(Job *, int, struct shf *);
157static Job		*j_lookup(const char *, int *);
158static Job		*new_job(void);
159static Proc		*new_proc(void);
160static void		check_job(Job *);
161static void		put_job(Job *, int);
162static void		remove_job(Job *, const char *);
163static int		kill_job(Job *, int);
164
165static void tty_init_talking(void);
166static void tty_init_state(void);
167
168/* initialise job control */
169void
170j_init(void)
171{
172#ifndef MKSH_UNEMPLOYED
173	bool mflagset = Flag(FMONITOR) != 127;
174
175	Flag(FMONITOR) = 0;
176#endif
177
178#ifndef MKSH_NOPROSPECTOFWORK
179	(void)sigemptyset(&sm_default);
180	sigprocmask(SIG_SETMASK, &sm_default, NULL);
181
182	(void)sigemptyset(&sm_sigchld);
183	(void)sigaddset(&sm_sigchld, SIGCHLD);
184
185	setsig(&sigtraps[SIGCHLD], j_sigchld,
186	    SS_RESTORE_ORIG|SS_FORCE|SS_SHTRAP);
187#else
188	/* Make sure SIGCHLD isn't ignored - can do odd things under SYSV */
189	setsig(&sigtraps[SIGCHLD], SIG_DFL, SS_RESTORE_ORIG|SS_FORCE);
190#endif
191
192#ifndef MKSH_UNEMPLOYED
193	if (!mflagset && Flag(FTALKING))
194		Flag(FMONITOR) = 1;
195
196	/*
197	 * shl_j is used to do asynchronous notification (used in
198	 * an interrupt handler, so need a distinct shf)
199	 */
200	shl_j = shf_fdopen(2, SHF_WR, NULL);
201
202	if (Flag(FMONITOR) || Flag(FTALKING)) {
203		int i;
204
205		/*
206		 * the TF_SHELL_USES test is a kludge that lets us know if
207		 * if the signals have been changed by the shell.
208		 */
209		for (i = NELEM(tt_sigs); --i >= 0; ) {
210			sigtraps[tt_sigs[i]].flags |= TF_SHELL_USES;
211			/* j_change() sets this to SS_RESTORE_DFL if FMONITOR */
212			setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
213			    SS_RESTORE_IGN|SS_FORCE);
214		}
215	}
216
217	/* j_change() calls tty_init_talking() and tty_init_state() */
218	if (Flag(FMONITOR))
219		j_change();
220	else
221#endif
222	  if (Flag(FTALKING)) {
223		tty_init_talking();
224		tty_init_state();
225	}
226}
227
228static int
229proc_errorlevel(Proc *p)
230{
231	switch (p->state) {
232	case PEXITED:
233		return ((WEXITSTATUS(p->status)) & 255);
234	case PSIGNALLED:
235		return (ksh_sigmask(WTERMSIG(p->status)));
236	default:
237		return (0);
238	}
239}
240
241#if !defined(MKSH_UNEMPLOYED) && HAVE_GETSID
242/* suspend the shell */
243void
244j_suspend(void)
245{
246	struct sigaction sa, osa;
247
248	/* Restore tty and pgrp. */
249	if (ttypgrp_ok) {
250		if (tty_hasstate)
251			mksh_tcset(tty_fd, &tty_state);
252		if (restore_ttypgrp >= 0) {
253			if (tcsetpgrp(tty_fd, restore_ttypgrp) < 0) {
254				warningf(false, Tf_ssfaileds,
255				    Tj_suspend, "tcsetpgrp", cstrerror(errno));
256			} else if (setpgid(0, restore_ttypgrp) < 0) {
257				warningf(false, Tf_ssfaileds,
258				    Tj_suspend, "setpgid", cstrerror(errno));
259			}
260		}
261	}
262
263	/* Suspend the shell. */
264	memset(&sa, 0, sizeof(sa));
265	sigemptyset(&sa.sa_mask);
266	sa.sa_handler = SIG_DFL;
267	sigaction(SIGTSTP, &sa, &osa);
268	kill(0, SIGTSTP);
269
270	/* Back from suspend, reset signals, pgrp and tty. */
271	sigaction(SIGTSTP, &osa, NULL);
272	if (ttypgrp_ok) {
273		if (restore_ttypgrp >= 0) {
274			if (setpgid(0, kshpid) < 0) {
275				warningf(false, Tf_ssfaileds,
276				    Tj_suspend, "setpgid", cstrerror(errno));
277				ttypgrp_ok = false;
278			} else if (tcsetpgrp(tty_fd, kshpid) < 0) {
279				warningf(false, Tf_ssfaileds,
280				    Tj_suspend, "tcsetpgrp", cstrerror(errno));
281				ttypgrp_ok = false;
282			}
283		}
284		tty_init_state();
285	}
286}
287#endif
288
289/* job cleanup before shell exit */
290void
291j_exit(void)
292{
293	/* kill stopped, and possibly running, jobs */
294	Job *j;
295	bool killed = false;
296
297	for (j = job_list; j != NULL; j = j->next) {
298		if (j->ppid == procpid &&
299		    (j->state == PSTOPPED ||
300		    (j->state == PRUNNING &&
301		    ((j->flags & JF_FG) ||
302		    (Flag(FLOGIN) && !Flag(FNOHUP) && procpid == kshpid))))) {
303			killed = true;
304			if (j->pgrp == 0)
305				kill_job(j, SIGHUP);
306			else
307				mksh_killpg(j->pgrp, SIGHUP);
308#ifndef MKSH_UNEMPLOYED
309			if (j->state == PSTOPPED) {
310				if (j->pgrp == 0)
311					kill_job(j, SIGCONT);
312				else
313					mksh_killpg(j->pgrp, SIGCONT);
314			}
315#endif
316		}
317	}
318	if (killed)
319		sleep(1);
320	j_notify();
321
322#ifndef MKSH_UNEMPLOYED
323	if (kshpid == procpid && restore_ttypgrp >= 0) {
324		/*
325		 * Need to restore the tty pgrp to what it was when the
326		 * shell started up, so that the process that started us
327		 * will be able to access the tty when we are done.
328		 * Also need to restore our process group in case we are
329		 * about to do an exec so that both our parent and the
330		 * process we are to become will be able to access the tty.
331		 */
332		tcsetpgrp(tty_fd, restore_ttypgrp);
333		setpgid(0, restore_ttypgrp);
334	}
335	if (Flag(FMONITOR)) {
336		Flag(FMONITOR) = 0;
337		j_change();
338	}
339#endif
340}
341
342#ifndef MKSH_UNEMPLOYED
343/* turn job control on or off according to Flag(FMONITOR) */
344void
345j_change(void)
346{
347	int i;
348
349	if (Flag(FMONITOR)) {
350		bool use_tty = Flag(FTALKING);
351
352		/* don't call mksh_tcget until we own the tty process group */
353		if (use_tty)
354			tty_init_talking();
355
356		/* no controlling tty, no SIGT* */
357		if ((ttypgrp_ok = (use_tty && tty_fd >= 0 && tty_devtty))) {
358			setsig(&sigtraps[SIGTTIN], SIG_DFL,
359			    SS_RESTORE_ORIG|SS_FORCE);
360			/* wait to be given tty (POSIX.1, B.2, job control) */
361			while (/* CONSTCOND */ 1) {
362				pid_t ttypgrp;
363
364				if ((ttypgrp = tcgetpgrp(tty_fd)) < 0) {
365					warningf(false, Tf_ssfaileds,
366					    "j_init", "tcgetpgrp",
367					    cstrerror(errno));
368					ttypgrp_ok = false;
369					break;
370				}
371				if (ttypgrp == kshpgrp)
372					break;
373				kill(0, SIGTTIN);
374			}
375		}
376		for (i = NELEM(tt_sigs); --i >= 0; )
377			setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
378			    SS_RESTORE_DFL|SS_FORCE);
379		if (ttypgrp_ok && kshpgrp != kshpid) {
380			if (setpgid(0, kshpid) < 0) {
381				warningf(false, Tf_ssfaileds,
382				    "j_init", "setpgid", cstrerror(errno));
383				ttypgrp_ok = false;
384			} else {
385				if (tcsetpgrp(tty_fd, kshpid) < 0) {
386					warningf(false, Tf_ssfaileds,
387					    "j_init", "tcsetpgrp",
388					    cstrerror(errno));
389					ttypgrp_ok = false;
390				} else
391					restore_ttypgrp = kshpgrp;
392				kshpgrp = kshpid;
393			}
394		}
395#ifndef MKSH_DISABLE_TTY_WARNING
396		if (use_tty && !ttypgrp_ok)
397			warningf(false, Tf_sD_s, "warning",
398			    "won't have full job control");
399#endif
400	} else {
401		ttypgrp_ok = false;
402		if (Flag(FTALKING))
403			for (i = NELEM(tt_sigs); --i >= 0; )
404				setsig(&sigtraps[tt_sigs[i]], SIG_IGN,
405				    SS_RESTORE_IGN|SS_FORCE);
406		else
407			for (i = NELEM(tt_sigs); --i >= 0; ) {
408				if (sigtraps[tt_sigs[i]].flags &
409				    (TF_ORIG_IGN | TF_ORIG_DFL))
410					setsig(&sigtraps[tt_sigs[i]],
411					    (sigtraps[tt_sigs[i]].flags & TF_ORIG_IGN) ?
412					    SIG_IGN : SIG_DFL,
413					    SS_RESTORE_ORIG|SS_FORCE);
414			}
415	}
416	tty_init_state();
417}
418#endif
419
420#if HAVE_NICE
421/* run nice(3) and ignore the result */
422static void
423ksh_nice(int ness)
424{
425#if defined(__USE_FORTIFY_LEVEL) && (__USE_FORTIFY_LEVEL > 0)
426	int eno;
427
428	errno = 0;
429	/* this is gonna annoy users; complain to your distro, people! */
430	if (nice(ness) == -1 && (eno = errno) != 0)
431		warningf(false, Tf_sD_s, "bgnice", cstrerror(eno));
432#else
433	(void)nice(ness);
434#endif
435}
436#endif
437
438/* execute tree in child subprocess */
439int
440exchild(struct op *t, int flags,
441    volatile int *xerrok,
442    /* used if XPCLOSE or XCCLOSE */
443    int close_fd)
444{
445	/* for pipelines */
446	static Proc *last_proc;
447
448	int rv = 0, forksleep, jwflags = JW_NONE;
449#ifndef MKSH_NOPROSPECTOFWORK
450	sigset_t omask;
451#endif
452	Proc *p;
453	Job *j;
454	pid_t cldpid;
455
456	if (flags & XPIPEST) {
457		flags &= ~XPIPEST;
458		jwflags |= JW_PIPEST;
459	}
460
461	if (flags & XEXEC)
462		/*
463		 * Clear XFORK|XPCLOSE|XCCLOSE|XCOPROC|XPIPEO|XPIPEI|XXCOM|XBGND
464		 * (also done in another execute() below)
465		 */
466		return (execute(t, flags & (XEXEC | XERROK), xerrok));
467
468#ifndef MKSH_NOPROSPECTOFWORK
469	/* no SIGCHLDs while messing with job and process lists */
470	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
471#endif
472
473	p = new_proc();
474	p->next = NULL;
475	p->state = PRUNNING;
476	p->status = 0;
477	p->pid = 0;
478
479	/* link process into jobs list */
480	if (flags & XPIPEI) {
481		/* continuing with a pipe */
482		if (!last_job)
483			internal_errorf("exchild: XPIPEI and no last_job - pid %d",
484			    (int)procpid);
485		j = last_job;
486		if (last_proc)
487			last_proc->next = p;
488		last_proc = p;
489	} else {
490		/* fills in j->job */
491		j = new_job();
492		/*
493		 * we don't consider XXCOMs foreground since they don't get
494		 * tty process group and we don't save or restore tty modes.
495		 */
496		j->flags = (flags & XXCOM) ? JF_XXCOM :
497		    ((flags & XBGND) ? 0 : (JF_FG|JF_USETTYMODE));
498		timerclear(&j->usrtime);
499		timerclear(&j->systime);
500		j->state = PRUNNING;
501		j->pgrp = 0;
502		j->ppid = procpid;
503		j->age = ++njobs;
504		j->proc_list = p;
505		j->coproc_id = 0;
506		last_job = j;
507		last_proc = p;
508		put_job(j, PJ_PAST_STOPPED);
509	}
510
511	vistree(p->command, sizeof(p->command), t);
512
513	/* create child process */
514	forksleep = 1;
515	while ((cldpid = fork()) < 0 && errno == EAGAIN && forksleep < 32) {
516		if (intrsig)
517			/* allow user to ^C out... */
518			break;
519		sleep(forksleep);
520		forksleep <<= 1;
521	}
522	/* ensure $RANDOM changes between parent and child */
523	rndset((unsigned long)cldpid);
524	/* fork failed? */
525	if (cldpid < 0) {
526		kill_job(j, SIGKILL);
527		remove_job(j, "fork failed");
528#ifndef MKSH_NOPROSPECTOFWORK
529		sigprocmask(SIG_SETMASK, &omask, NULL);
530#endif
531		errorf("can't fork - try again");
532	}
533	p->pid = cldpid ? cldpid : (procpid = getpid());
534
535#ifndef MKSH_UNEMPLOYED
536	/* job control set up */
537	if (Flag(FMONITOR) && !(flags&XXCOM)) {
538		bool dotty = false;
539
540		if (j->pgrp == 0) {
541			/* First process */
542			j->pgrp = p->pid;
543			dotty = true;
544		}
545
546		/*
547		 * set pgrp in both parent and child to deal with race
548		 * condition
549		 */
550		setpgid(p->pid, j->pgrp);
551		if (ttypgrp_ok && dotty && !(flags & XBGND))
552			tcsetpgrp(tty_fd, j->pgrp);
553	}
554#endif
555
556	/* used to close pipe input fd */
557	if (close_fd >= 0 && (((flags & XPCLOSE) && cldpid) ||
558	    ((flags & XCCLOSE) && !cldpid)))
559		close(close_fd);
560	if (!cldpid) {
561		/* child */
562
563		/* Do this before restoring signal */
564		if (flags & XCOPROC)
565			coproc_cleanup(false);
566		cleanup_parents_env();
567#ifndef MKSH_UNEMPLOYED
568		/*
569		 * If FMONITOR or FTALKING is set, these signals are ignored,
570		 * if neither FMONITOR nor FTALKING are set, the signals have
571		 * their inherited values.
572		 */
573		if (Flag(FMONITOR) && !(flags & XXCOM)) {
574			for (forksleep = NELEM(tt_sigs); --forksleep >= 0; )
575				setsig(&sigtraps[tt_sigs[forksleep]], SIG_DFL,
576				    SS_RESTORE_DFL|SS_FORCE);
577		}
578#endif
579#if HAVE_NICE
580		if (Flag(FBGNICE) && (flags & XBGND))
581			ksh_nice(4);
582#endif
583		if ((flags & XBGND)
584#ifndef MKSH_UNEMPLOYED
585		    && !Flag(FMONITOR)
586#endif
587		    ) {
588			setsig(&sigtraps[SIGINT], SIG_IGN,
589			    SS_RESTORE_IGN|SS_FORCE);
590			setsig(&sigtraps[SIGQUIT], SIG_IGN,
591			    SS_RESTORE_IGN|SS_FORCE);
592			if ((!(flags & (XPIPEI | XCOPROC))) &&
593			    ((forksleep = open("/dev/null", 0)) > 0)) {
594				(void)ksh_dup2(forksleep, 0, true);
595				close(forksleep);
596			}
597		}
598		/* in case of $(jobs) command */
599		remove_job(j, "child");
600#ifndef MKSH_NOPROSPECTOFWORK
601		/* remove_job needs SIGCHLD blocked still */
602		sigprocmask(SIG_SETMASK, &omask, NULL);
603#endif
604		nzombie = 0;
605#ifndef MKSH_UNEMPLOYED
606		ttypgrp_ok = false;
607		Flag(FMONITOR) = 0;
608#endif
609		Flag(FTALKING) = 0;
610		cleartraps();
611		/* no return */
612		execute(t, (flags & XERROK) | XEXEC, NULL);
613#ifndef MKSH_SMALL
614		if (t->type == TPIPE)
615			unwind(LLEAVE);
616		internal_warningf("%s: execute() returned", "exchild");
617		fptreef(shl_out, 8, "%s: tried to execute {\n\t%T\n}\n",
618		    "exchild", t);
619		shf_flush(shl_out);
620#endif
621		unwind(LLEAVE);
622		/* NOTREACHED */
623	}
624
625	/* shell (parent) stuff */
626	if (!(flags & XPIPEO)) {
627		/* last process in a job */
628		j_startjob(j);
629		if (flags & XCOPROC) {
630			j->coproc_id = coproc.id;
631			/* n jobs using co-process output */
632			coproc.njobs++;
633			/* j using co-process input */
634			coproc.job = (void *)j;
635		}
636		if (flags & XBGND) {
637			j_set_async(j);
638			if (Flag(FTALKING)) {
639				shf_fprintf(shl_out, "[%d]", j->job);
640				for (p = j->proc_list; p; p = p->next)
641					shf_fprintf(shl_out, Tf__d,
642					    (int)p->pid);
643				shf_putchar('\n', shl_out);
644				shf_flush(shl_out);
645			}
646		} else
647			rv = j_waitj(j, jwflags, "jw:last proc");
648	}
649
650#ifndef MKSH_NOPROSPECTOFWORK
651	sigprocmask(SIG_SETMASK, &omask, NULL);
652#endif
653
654	return (rv);
655}
656
657/* start the last job: only used for $(command) jobs */
658void
659startlast(void)
660{
661#ifndef MKSH_NOPROSPECTOFWORK
662	sigset_t omask;
663
664	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
665#endif
666
667	/* no need to report error - waitlast() will do it */
668	if (last_job) {
669		/* ensure it isn't removed by check_job() */
670		last_job->flags |= JF_WAITING;
671		j_startjob(last_job);
672	}
673#ifndef MKSH_NOPROSPECTOFWORK
674	sigprocmask(SIG_SETMASK, &omask, NULL);
675#endif
676}
677
678/* wait for last job: only used for $(command) jobs */
679int
680waitlast(void)
681{
682	int rv;
683	Job *j;
684#ifndef MKSH_NOPROSPECTOFWORK
685	sigset_t omask;
686
687	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
688#endif
689
690	j = last_job;
691	if (!j || !(j->flags & JF_STARTED)) {
692		if (!j)
693			warningf(true, Tf_sD_s, "waitlast", "no last job");
694		else
695			internal_warningf(Tf_sD_s, "waitlast", Tnot_started);
696#ifndef MKSH_NOPROSPECTOFWORK
697		sigprocmask(SIG_SETMASK, &omask, NULL);
698#endif
699		/* not so arbitrary, non-zero value */
700		return (125);
701	}
702
703	rv = j_waitj(j, JW_NONE, "waitlast");
704
705#ifndef MKSH_NOPROSPECTOFWORK
706	sigprocmask(SIG_SETMASK, &omask, NULL);
707#endif
708
709	return (rv);
710}
711
712/* wait for child, interruptable. */
713int
714waitfor(const char *cp, int *sigp)
715{
716	int rv, ecode, flags = JW_INTERRUPT|JW_ASYNCNOTIFY;
717	Job *j;
718#ifndef MKSH_NOPROSPECTOFWORK
719	sigset_t omask;
720
721	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
722#endif
723
724	*sigp = 0;
725
726	if (cp == NULL) {
727		/*
728		 * wait for an unspecified job - always returns 0, so
729		 * don't have to worry about exited/signaled jobs
730		 */
731		for (j = job_list; j; j = j->next)
732			/* AT&T ksh will wait for stopped jobs - we don't */
733			if (j->ppid == procpid && j->state == PRUNNING)
734				break;
735		if (!j) {
736#ifndef MKSH_NOPROSPECTOFWORK
737			sigprocmask(SIG_SETMASK, &omask, NULL);
738#endif
739			return (-1);
740		}
741	} else if ((j = j_lookup(cp, &ecode))) {
742		/* don't report normal job completion */
743		flags &= ~JW_ASYNCNOTIFY;
744		if (j->ppid != procpid) {
745#ifndef MKSH_NOPROSPECTOFWORK
746			sigprocmask(SIG_SETMASK, &omask, NULL);
747#endif
748			return (-1);
749		}
750	} else {
751#ifndef MKSH_NOPROSPECTOFWORK
752		sigprocmask(SIG_SETMASK, &omask, NULL);
753#endif
754		if (ecode != JL_NOSUCH)
755			bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
756		return (-1);
757	}
758
759	/* AT&T ksh will wait for stopped jobs - we don't */
760	rv = j_waitj(j, flags, "jw:waitfor");
761
762#ifndef MKSH_NOPROSPECTOFWORK
763	sigprocmask(SIG_SETMASK, &omask, NULL);
764#endif
765
766	if (rv < 0)
767		/* we were interrupted */
768		*sigp = ksh_sigmask(-rv);
769
770	return (rv);
771}
772
773/* kill (built-in) a job */
774int
775j_kill(const char *cp, int sig)
776{
777	Job *j;
778	int rv = 0, ecode;
779#ifndef MKSH_NOPROSPECTOFWORK
780	sigset_t omask;
781
782	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
783#endif
784
785	if ((j = j_lookup(cp, &ecode)) == NULL) {
786#ifndef MKSH_NOPROSPECTOFWORK
787		sigprocmask(SIG_SETMASK, &omask, NULL);
788#endif
789		bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
790		return (1);
791	}
792
793	if (j->pgrp == 0) {
794		/* started when !Flag(FMONITOR) */
795		if (kill_job(j, sig) < 0) {
796			bi_errorf(Tf_sD_s, cp, cstrerror(errno));
797			rv = 1;
798		}
799	} else {
800#ifndef MKSH_UNEMPLOYED
801		if (j->state == PSTOPPED && (sig == SIGTERM || sig == SIGHUP))
802			mksh_killpg(j->pgrp, SIGCONT);
803#endif
804		if (mksh_killpg(j->pgrp, sig) < 0) {
805			bi_errorf(Tf_sD_s, cp, cstrerror(errno));
806			rv = 1;
807		}
808	}
809
810#ifndef MKSH_NOPROSPECTOFWORK
811	sigprocmask(SIG_SETMASK, &omask, NULL);
812#endif
813
814	return (rv);
815}
816
817#ifndef MKSH_UNEMPLOYED
818/* fg and bg built-ins: called only if Flag(FMONITOR) set */
819int
820j_resume(const char *cp, int bg)
821{
822	Job *j;
823	Proc *p;
824	int ecode, rv = 0;
825	bool running;
826	sigset_t omask;
827
828	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
829
830	if ((j = j_lookup(cp, &ecode)) == NULL) {
831		sigprocmask(SIG_SETMASK, &omask, NULL);
832		bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
833		return (1);
834	}
835
836	if (j->pgrp == 0) {
837		sigprocmask(SIG_SETMASK, &omask, NULL);
838		bi_errorf("job not job-controlled");
839		return (1);
840	}
841
842	if (bg)
843		shprintf("[%d] ", j->job);
844
845	running = false;
846	for (p = j->proc_list; p != NULL; p = p->next) {
847		if (p->state == PSTOPPED) {
848			p->state = PRUNNING;
849			p->status = 0;
850			running = true;
851		}
852		shf_puts(p->command, shl_stdout);
853		if (p->next)
854			shf_puts("| ", shl_stdout);
855	}
856	shf_putc('\n', shl_stdout);
857	shf_flush(shl_stdout);
858	if (running)
859		j->state = PRUNNING;
860
861	put_job(j, PJ_PAST_STOPPED);
862	if (bg)
863		j_set_async(j);
864	else {
865		/* attach tty to job */
866		if (j->state == PRUNNING) {
867			if (ttypgrp_ok && (j->flags & JF_SAVEDTTY))
868				mksh_tcset(tty_fd, &j->ttystat);
869			/* See comment in j_waitj regarding saved_ttypgrp. */
870			if (ttypgrp_ok &&
871			    tcsetpgrp(tty_fd, (j->flags & JF_SAVEDTTYPGRP) ?
872			    j->saved_ttypgrp : j->pgrp) < 0) {
873				rv = errno;
874				if (j->flags & JF_SAVEDTTY)
875					mksh_tcset(tty_fd, &tty_state);
876				sigprocmask(SIG_SETMASK, &omask, NULL);
877				bi_errorf(Tf_ldfailed,
878				    "fg: 1st", "tcsetpgrp", tty_fd,
879				    (long)((j->flags & JF_SAVEDTTYPGRP) ?
880				    j->saved_ttypgrp : j->pgrp),
881				    cstrerror(rv));
882				return (1);
883			}
884		}
885		j->flags |= JF_FG;
886		j->flags &= ~JF_KNOWN;
887		if (j == async_job)
888			async_job = NULL;
889	}
890
891	if (j->state == PRUNNING && mksh_killpg(j->pgrp, SIGCONT) < 0) {
892		int eno = errno;
893
894		if (!bg) {
895			j->flags &= ~JF_FG;
896			if (ttypgrp_ok && (j->flags & JF_SAVEDTTY))
897				mksh_tcset(tty_fd, &tty_state);
898			if (ttypgrp_ok && tcsetpgrp(tty_fd, kshpgrp) < 0)
899				warningf(true, Tf_ldfailed,
900				    "fg: 2nd", "tcsetpgrp", tty_fd,
901				    (long)kshpgrp, cstrerror(errno));
902		}
903		sigprocmask(SIG_SETMASK, &omask, NULL);
904		bi_errorf(Tf_s_sD_s, "can't continue job",
905		    cp, cstrerror(eno));
906		return (1);
907	}
908	if (!bg) {
909		if (ttypgrp_ok) {
910			j->flags &= ~(JF_SAVEDTTY | JF_SAVEDTTYPGRP);
911		}
912		rv = j_waitj(j, JW_NONE, "jw:resume");
913	}
914	sigprocmask(SIG_SETMASK, &omask, NULL);
915	return (rv);
916}
917#endif
918
919/* are there any running or stopped jobs ? */
920int
921j_stopped_running(void)
922{
923	Job *j;
924	int which = 0;
925
926	for (j = job_list; j != NULL; j = j->next) {
927#ifndef MKSH_UNEMPLOYED
928		if (j->ppid == procpid && j->state == PSTOPPED)
929			which |= 1;
930#endif
931		if (Flag(FLOGIN) && !Flag(FNOHUP) && procpid == kshpid &&
932		    j->ppid == procpid && j->state == PRUNNING)
933			which |= 2;
934	}
935	if (which) {
936		shellf("You have %s%s%s jobs\n",
937		    which & 1 ? "stopped" : "",
938		    which == 3 ? " and " : "",
939		    which & 2 ? "running" : "");
940		return (1);
941	}
942
943	return (0);
944}
945
946
947/* list jobs for jobs built-in */
948int
949j_jobs(const char *cp, int slp,
950    /* 0: short, 1: long, 2: pgrp */
951    int nflag)
952{
953	Job *j, *tmp;
954	int how, zflag = 0;
955#ifndef MKSH_NOPROSPECTOFWORK
956	sigset_t omask;
957
958	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
959#endif
960
961	if (nflag < 0) {
962		/* kludge: print zombies */
963		nflag = 0;
964		zflag = 1;
965	}
966	if (cp) {
967		int ecode;
968
969		if ((j = j_lookup(cp, &ecode)) == NULL) {
970#ifndef MKSH_NOPROSPECTOFWORK
971			sigprocmask(SIG_SETMASK, &omask, NULL);
972#endif
973			bi_errorf(Tf_sD_s, cp, lookup_msgs[ecode]);
974			return (1);
975		}
976	} else
977		j = job_list;
978	how = slp == 0 ? JP_MEDIUM : (slp == 1 ? JP_LONG : JP_PGRP);
979	for (; j; j = j->next) {
980		if ((!(j->flags & JF_ZOMBIE) || zflag) &&
981		    (!nflag || (j->flags & JF_CHANGED))) {
982			j_print(j, how, shl_stdout);
983			if (j->state == PEXITED || j->state == PSIGNALLED)
984				j->flags |= JF_REMOVE;
985		}
986		if (cp)
987			break;
988	}
989	/* Remove jobs after printing so there won't be multiple + or - jobs */
990	for (j = job_list; j; j = tmp) {
991		tmp = j->next;
992		if (j->flags & JF_REMOVE)
993			remove_job(j, Tjobs);
994	}
995#ifndef MKSH_NOPROSPECTOFWORK
996	sigprocmask(SIG_SETMASK, &omask, NULL);
997#endif
998	return (0);
999}
1000
1001/* list jobs for top-level notification */
1002void
1003j_notify(void)
1004{
1005	Job *j, *tmp;
1006#ifndef MKSH_NOPROSPECTOFWORK
1007	sigset_t omask;
1008
1009	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
1010#endif
1011	for (j = job_list; j; j = j->next) {
1012#ifndef MKSH_UNEMPLOYED
1013		if (Flag(FMONITOR) && (j->flags & JF_CHANGED))
1014			j_print(j, JP_MEDIUM, shl_out);
1015#endif
1016		/*
1017		 * Remove job after doing reports so there aren't
1018		 * multiple +/- jobs.
1019		 */
1020		if (j->state == PEXITED || j->state == PSIGNALLED)
1021			j->flags |= JF_REMOVE;
1022	}
1023	for (j = job_list; j; j = tmp) {
1024		tmp = j->next;
1025		if (j->flags & JF_REMOVE) {
1026			if (j == async_job || (j->flags & JF_KNOWN)) {
1027				j->flags = (j->flags & ~JF_REMOVE) | JF_ZOMBIE;
1028				j->job = -1;
1029				nzombie++;
1030			} else
1031				remove_job(j, "notify");
1032		}
1033	}
1034	shf_flush(shl_out);
1035#ifndef MKSH_NOPROSPECTOFWORK
1036	sigprocmask(SIG_SETMASK, &omask, NULL);
1037#endif
1038}
1039
1040/* Return pid of last process in last asynchronous job */
1041pid_t
1042j_async(void)
1043{
1044#ifndef MKSH_NOPROSPECTOFWORK
1045	sigset_t omask;
1046
1047	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
1048#endif
1049
1050	if (async_job)
1051		async_job->flags |= JF_KNOWN;
1052
1053#ifndef MKSH_NOPROSPECTOFWORK
1054	sigprocmask(SIG_SETMASK, &omask, NULL);
1055#endif
1056
1057	return (async_pid);
1058}
1059
1060/*
1061 * Make j the last async process
1062 *
1063 * If jobs are compiled in then this routine expects sigchld to be blocked.
1064 */
1065static void
1066j_set_async(Job *j)
1067{
1068	Job *jl, *oldest;
1069
1070	if (async_job && (async_job->flags & (JF_KNOWN|JF_ZOMBIE)) == JF_ZOMBIE)
1071		remove_job(async_job, "async");
1072	if (!(j->flags & JF_STARTED)) {
1073		internal_warningf(Tf_sD_s, "j_async", Tjob_not_started);
1074		return;
1075	}
1076	async_job = j;
1077	async_pid = j->last_proc->pid;
1078	while (nzombie > CHILD_MAX) {
1079		oldest = NULL;
1080		for (jl = job_list; jl; jl = jl->next)
1081			if (jl != async_job && (jl->flags & JF_ZOMBIE) &&
1082			    (!oldest || jl->age < oldest->age))
1083				oldest = jl;
1084		if (!oldest) {
1085			/* XXX debugging */
1086			if (!(async_job->flags & JF_ZOMBIE) || nzombie != 1) {
1087				internal_warningf("%s: bad nzombie (%d)",
1088				    "j_async", nzombie);
1089				nzombie = 0;
1090			}
1091			break;
1092		}
1093		remove_job(oldest, "zombie");
1094	}
1095}
1096
1097/*
1098 * Start a job: set STARTED, check for held signals and set j->last_proc
1099 *
1100 * If jobs are compiled in then this routine expects sigchld to be blocked.
1101 */
1102static void
1103j_startjob(Job *j)
1104{
1105	Proc *p;
1106
1107	j->flags |= JF_STARTED;
1108	for (p = j->proc_list; p->next; p = p->next)
1109		;
1110	j->last_proc = p;
1111
1112#ifndef MKSH_NOPROSPECTOFWORK
1113	if (held_sigchld) {
1114		held_sigchld = 0;
1115		/* Don't call j_sigchld() as it may remove job... */
1116		kill(procpid, SIGCHLD);
1117	}
1118#endif
1119}
1120
1121/*
1122 * wait for job to complete or change state
1123 *
1124 * If jobs are compiled in then this routine expects sigchld to be blocked.
1125 */
1126static int
1127j_waitj(Job *j,
1128    /* see JW_* */
1129    int flags,
1130    const char *where)
1131{
1132	Proc *p;
1133	int rv;
1134#ifdef MKSH_NO_SIGSUSPEND
1135	sigset_t omask;
1136#endif
1137
1138	/*
1139	 * No auto-notify on the job we are waiting on.
1140	 */
1141	j->flags |= JF_WAITING;
1142	if (flags & JW_ASYNCNOTIFY)
1143		j->flags |= JF_W_ASYNCNOTIFY;
1144
1145#ifndef MKSH_UNEMPLOYED
1146	if (!Flag(FMONITOR))
1147#endif
1148		flags |= JW_STOPPEDWAIT;
1149
1150	while (j->state == PRUNNING ||
1151	    ((flags & JW_STOPPEDWAIT) && j->state == PSTOPPED)) {
1152#ifndef MKSH_NOPROSPECTOFWORK
1153#ifdef MKSH_NO_SIGSUSPEND
1154		sigprocmask(SIG_SETMASK, &sm_default, &omask);
1155		pause();
1156		/* note that handlers may run here so they need to know */
1157		sigprocmask(SIG_SETMASK, &omask, NULL);
1158#else
1159		sigsuspend(&sm_default);
1160#endif
1161#else
1162		j_sigchld(SIGCHLD);
1163#endif
1164		if (fatal_trap) {
1165			int oldf = j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY);
1166			j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
1167			runtraps(TF_FATAL);
1168			/* not reached... */
1169			j->flags |= oldf;
1170		}
1171		if ((flags & JW_INTERRUPT) && (rv = trap_pending())) {
1172			j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
1173			return (-rv);
1174		}
1175	}
1176	j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
1177
1178	if (j->flags & JF_FG) {
1179		j->flags &= ~JF_FG;
1180#ifndef MKSH_UNEMPLOYED
1181		if (Flag(FMONITOR) && ttypgrp_ok && j->pgrp) {
1182			/*
1183			 * Save the tty's current pgrp so it can be restored
1184			 * when the job is foregrounded. This is to
1185			 * deal with things like the GNU su which does
1186			 * a fork/exec instead of an exec (the fork means
1187			 * the execed shell gets a different pid from its
1188			 * pgrp, so naturally it sets its pgrp and gets hosed
1189			 * when it gets foregrounded by the parent shell which
1190			 * has restored the tty's pgrp to that of the su
1191			 * process).
1192			 */
1193			if (j->state == PSTOPPED &&
1194			    (j->saved_ttypgrp = tcgetpgrp(tty_fd)) >= 0)
1195				j->flags |= JF_SAVEDTTYPGRP;
1196			if (tcsetpgrp(tty_fd, kshpgrp) < 0)
1197				warningf(true, Tf_ldfailed,
1198				    "j_waitj:", "tcsetpgrp", tty_fd,
1199				    (long)kshpgrp, cstrerror(errno));
1200			if (j->state == PSTOPPED) {
1201				j->flags |= JF_SAVEDTTY;
1202				mksh_tcget(tty_fd, &j->ttystat);
1203			}
1204		}
1205#endif
1206		if (tty_hasstate) {
1207			/*
1208			 * Only restore tty settings if job was originally
1209			 * started in the foreground. Problems can be
1210			 * caused by things like 'more foobar &' which will
1211			 * typically get and save the shell's vi/emacs tty
1212			 * settings before setting up the tty for itself;
1213			 * when more exits, it restores the 'original'
1214			 * settings, and things go down hill from there...
1215			 */
1216			if (j->state == PEXITED && j->status == 0 &&
1217			    (j->flags & JF_USETTYMODE)) {
1218				mksh_tcget(tty_fd, &tty_state);
1219			} else {
1220				mksh_tcset(tty_fd, &tty_state);
1221				/*-
1222				 * Don't use tty mode if job is stopped and
1223				 * later restarted and exits. Consider
1224				 * the sequence:
1225				 *	vi foo (stopped)
1226				 *	...
1227				 *	stty something
1228				 *	...
1229				 *	fg (vi; ZZ)
1230				 * mode should be that of the stty, not what
1231				 * was before the vi started.
1232				 */
1233				if (j->state == PSTOPPED)
1234					j->flags &= ~JF_USETTYMODE;
1235			}
1236		}
1237#ifndef MKSH_UNEMPLOYED
1238		/*
1239		 * If it looks like user hit ^C to kill a job, pretend we got
1240		 * one too to break out of for loops, etc. (AT&T ksh does this
1241		 * even when not monitoring, but this doesn't make sense since
1242		 * a tty generated ^C goes to the whole process group)
1243		 */
1244		if (Flag(FMONITOR) && j->state == PSIGNALLED &&
1245		    WIFSIGNALED(j->last_proc->status)) {
1246			int termsig;
1247
1248			if ((termsig = WTERMSIG(j->last_proc->status)) > 0 &&
1249			    termsig < ksh_NSIG &&
1250			    (sigtraps[termsig].flags & TF_TTY_INTR))
1251				trapsig(termsig);
1252		}
1253#endif
1254	}
1255
1256	j_usrtime = j->usrtime;
1257	j_systime = j->systime;
1258	rv = j->status;
1259
1260	if (!(p = j->proc_list)) {
1261		;	/* nothing */
1262	} else if (flags & JW_PIPEST) {
1263		uint32_t num = 0;
1264		struct tbl *vp;
1265
1266		unset(vp_pipest, 1);
1267		vp = vp_pipest;
1268		vp->flag = DEFINED | ISSET | INTEGER | RDONLY | ARRAY | INT_U;
1269		goto got_array;
1270
1271		while (p != NULL) {
1272			{
1273				struct tbl *vq;
1274
1275				/* strlen(vp_pipest->name) == 10 */
1276				vq = alloc(offsetof(struct tbl, name[0]) + 11,
1277				    vp_pipest->areap);
1278				memset(vq, 0, offsetof(struct tbl, name[0]));
1279				memcpy(vq->name, vp_pipest->name, 11);
1280				vp->u.array = vq;
1281				vp = vq;
1282			}
1283			vp->areap = vp_pipest->areap;
1284			vp->ua.index = ++num;
1285			vp->flag = DEFINED | ISSET | INTEGER | RDONLY |
1286			    ARRAY | INT_U | AINDEX;
1287 got_array:
1288			vp->val.i = proc_errorlevel(p);
1289			if (Flag(FPIPEFAIL) && vp->val.i)
1290				rv = vp->val.i;
1291			p = p->next;
1292		}
1293	} else if (Flag(FPIPEFAIL)) {
1294		do {
1295			const int i = proc_errorlevel(p);
1296
1297			if (i)
1298				rv = i;
1299		} while ((p = p->next));
1300	}
1301
1302	if (!(flags & JW_ASYNCNOTIFY)
1303#ifndef MKSH_UNEMPLOYED
1304	    && (!Flag(FMONITOR) || j->state != PSTOPPED)
1305#endif
1306	    ) {
1307		j_print(j, JP_SHORT, shl_out);
1308		shf_flush(shl_out);
1309	}
1310	if (j->state != PSTOPPED
1311#ifndef MKSH_UNEMPLOYED
1312	    && (!Flag(FMONITOR) || !(flags & JW_ASYNCNOTIFY))
1313#endif
1314	    )
1315		remove_job(j, where);
1316
1317	return (rv);
1318}
1319
1320/*
1321 * SIGCHLD handler to reap children and update job states
1322 *
1323 * If jobs are compiled in then this routine expects sigchld to be blocked.
1324 */
1325/* ARGSUSED */
1326static void
1327j_sigchld(int sig MKSH_A_UNUSED)
1328{
1329	int saved_errno = errno;
1330	Job *j;
1331	Proc *p = NULL;
1332	pid_t pid;
1333	int status;
1334	struct rusage ru0, ru1;
1335#ifdef MKSH_NO_SIGSUSPEND
1336	sigset_t omask;
1337
1338	/* this handler can run while SIGCHLD is not blocked, so block it now */
1339	sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
1340#endif
1341
1342#ifndef MKSH_NOPROSPECTOFWORK
1343	/*
1344	 * Don't wait for any processes if a job is partially started.
1345	 * This is so we don't do away with the process group leader
1346	 * before all the processes in a pipe line are started (so the
1347	 * setpgid() won't fail)
1348	 */
1349	for (j = job_list; j; j = j->next)
1350		if (j->ppid == procpid && !(j->flags & JF_STARTED)) {
1351			held_sigchld = 1;
1352			goto j_sigchld_out;
1353		}
1354#endif
1355
1356	getrusage(RUSAGE_CHILDREN, &ru0);
1357	do {
1358#ifndef MKSH_NOPROSPECTOFWORK
1359		pid = waitpid(-1, &status, (WNOHANG |
1360#if defined(WCONTINUED) && defined(WIFCONTINUED)
1361		    WCONTINUED |
1362#endif
1363		    WUNTRACED));
1364#else
1365		pid = wait(&status);
1366#endif
1367
1368		/*
1369		 * return if this would block (0) or no children
1370		 * or interrupted (-1)
1371		 */
1372		if (pid <= 0)
1373			goto j_sigchld_out;
1374
1375		getrusage(RUSAGE_CHILDREN, &ru1);
1376
1377		/* find job and process structures for this pid */
1378		for (j = job_list; j != NULL; j = j->next)
1379			for (p = j->proc_list; p != NULL; p = p->next)
1380				if (p->pid == pid)
1381					goto found;
1382 found:
1383		if (j == NULL) {
1384			/* Can occur if process has kids, then execs shell
1385			warningf(true, "bad process waited for (pid = %d)",
1386				pid);
1387			 */
1388			ru0 = ru1;
1389			continue;
1390		}
1391
1392		timeradd(&j->usrtime, &ru1.ru_utime, &j->usrtime);
1393		timersub(&j->usrtime, &ru0.ru_utime, &j->usrtime);
1394		timeradd(&j->systime, &ru1.ru_stime, &j->systime);
1395		timersub(&j->systime, &ru0.ru_stime, &j->systime);
1396		ru0 = ru1;
1397		p->status = status;
1398#ifndef MKSH_UNEMPLOYED
1399		if (WIFSTOPPED(status))
1400			p->state = PSTOPPED;
1401		else
1402#if defined(WCONTINUED) && defined(WIFCONTINUED)
1403		  if (WIFCONTINUED(status)) {
1404			p->state = j->state = PRUNNING;
1405			/* skip check_job(), no-op in this case */
1406			continue;
1407		} else
1408#endif
1409#endif
1410		  if (WIFSIGNALED(status))
1411			p->state = PSIGNALLED;
1412		else
1413			p->state = PEXITED;
1414
1415		/* check to see if entire job is done */
1416		check_job(j);
1417	}
1418#ifndef MKSH_NOPROSPECTOFWORK
1419	    while (/* CONSTCOND */ 1);
1420#else
1421	    while (/* CONSTCOND */ 0);
1422#endif
1423
1424 j_sigchld_out:
1425#ifdef MKSH_NO_SIGSUSPEND
1426	sigprocmask(SIG_SETMASK, &omask, NULL);
1427#endif
1428	errno = saved_errno;
1429}
1430
1431/*
1432 * Called only when a process in j has exited/stopped (ie, called only
1433 * from j_sigchld()). If no processes are running, the job status
1434 * and state are updated, asynchronous job notification is done and,
1435 * if unneeded, the job is removed.
1436 *
1437 * If jobs are compiled in then this routine expects sigchld to be blocked.
1438 */
1439static void
1440check_job(Job *j)
1441{
1442	int jstate;
1443	Proc *p;
1444
1445	/* XXX debugging (nasty - interrupt routine using shl_out) */
1446	if (!(j->flags & JF_STARTED)) {
1447		internal_warningf("check_job: job started (flags 0x%X)",
1448		    (unsigned int)j->flags);
1449		return;
1450	}
1451
1452	jstate = PRUNNING;
1453	for (p=j->proc_list; p != NULL; p = p->next) {
1454		if (p->state == PRUNNING)
1455			/* some processes still running */
1456			return;
1457		if (p->state > jstate)
1458			jstate = p->state;
1459	}
1460	j->state = jstate;
1461	j->status = proc_errorlevel(j->last_proc);
1462
1463	/*
1464	 * Note when co-process dies: can't be done in j_wait() nor
1465	 * remove_job() since neither may be called for non-interactive
1466	 * shells.
1467	 */
1468	if (j->state == PEXITED || j->state == PSIGNALLED) {
1469		/*
1470		 * No need to keep co-process input any more
1471		 * (at least, this is what ksh93d thinks)
1472		 */
1473		if (coproc.job == j) {
1474			coproc.job = NULL;
1475			/*
1476			 * XXX would be nice to get the closes out of here
1477			 * so they aren't done in the signal handler.
1478			 * Would mean a check in coproc_getfd() to
1479			 * do "if job == 0 && write >= 0, close write".
1480			 */
1481			coproc_write_close(coproc.write);
1482		}
1483		/* Do we need to keep the output? */
1484		if (j->coproc_id && j->coproc_id == coproc.id &&
1485		    --coproc.njobs == 0)
1486			coproc_readw_close(coproc.read);
1487	}
1488
1489	j->flags |= JF_CHANGED;
1490#ifndef MKSH_UNEMPLOYED
1491	if (Flag(FMONITOR) && !(j->flags & JF_XXCOM)) {
1492		/*
1493		 * Only put stopped jobs at the front to avoid confusing
1494		 * the user (don't want finished jobs effecting %+ or %-)
1495		 */
1496		if (j->state == PSTOPPED)
1497			put_job(j, PJ_ON_FRONT);
1498		if (Flag(FNOTIFY) &&
1499		    (j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY)) != JF_WAITING) {
1500			/* Look for the real file descriptor 2 */
1501			{
1502				struct env *ep;
1503				int fd = 2;
1504
1505				for (ep = e; ep; ep = ep->oenv)
1506					if (ep->savefd && ep->savefd[2])
1507						fd = ep->savefd[2];
1508				shf_reopen(fd, SHF_WR, shl_j);
1509			}
1510			/*
1511			 * Can't call j_notify() as it removes jobs. The job
1512			 * must stay in the job list as j_waitj() may be
1513			 * running with this job.
1514			 */
1515			j_print(j, JP_MEDIUM, shl_j);
1516			shf_flush(shl_j);
1517			if (!(j->flags & JF_WAITING) && j->state != PSTOPPED)
1518				remove_job(j, "notify");
1519		}
1520	}
1521#endif
1522	if (
1523#ifndef MKSH_UNEMPLOYED
1524	    !Flag(FMONITOR) &&
1525#endif
1526	    !(j->flags & (JF_WAITING|JF_FG)) &&
1527	    j->state != PSTOPPED) {
1528		if (j == async_job || (j->flags & JF_KNOWN)) {
1529			j->flags |= JF_ZOMBIE;
1530			j->job = -1;
1531			nzombie++;
1532		} else
1533			remove_job(j, "checkjob");
1534	}
1535}
1536
1537/*
1538 * Print job status in either short, medium or long format.
1539 *
1540 * If jobs are compiled in then this routine expects sigchld to be blocked.
1541 */
1542static void
1543j_print(Job *j, int how, struct shf *shf)
1544{
1545	Proc *p;
1546	int state;
1547	int status;
1548#ifdef WCOREDUMP
1549	bool coredumped;
1550#endif
1551	char jobchar = ' ';
1552	char buf[64];
1553	const char *filler;
1554	int output = 0;
1555
1556	if (how == JP_PGRP) {
1557		/*
1558		 * POSIX doesn't say what to do it there is no process
1559		 * group leader (ie, !FMONITOR). We arbitrarily return
1560		 * last pid (which is what $! returns).
1561		 */
1562		shf_fprintf(shf, Tf_dN, (int)(j->pgrp ? j->pgrp :
1563		    (j->last_proc ? j->last_proc->pid : 0)));
1564		return;
1565	}
1566	j->flags &= ~JF_CHANGED;
1567	filler = j->job > 10 ? "\n       " : "\n      ";
1568	if (j == job_list)
1569		jobchar = '+';
1570	else if (j == job_list->next)
1571		jobchar = '-';
1572
1573	for (p = j->proc_list; p != NULL;) {
1574#ifdef WCOREDUMP
1575		coredumped = false;
1576#endif
1577		switch (p->state) {
1578		case PRUNNING:
1579			memcpy(buf, "Running", 8);
1580			break;
1581		case PSTOPPED: {
1582			int stopsig = WSTOPSIG(p->status);
1583
1584			strlcpy(buf, stopsig > 0 && stopsig < ksh_NSIG ?
1585			    sigtraps[stopsig].mess : "Stopped", sizeof(buf));
1586			break;
1587		}
1588		case PEXITED: {
1589			int exitstatus = (WEXITSTATUS(p->status)) & 255;
1590
1591			if (how == JP_SHORT)
1592				buf[0] = '\0';
1593			else if (exitstatus == 0)
1594				memcpy(buf, "Done", 5);
1595			else
1596				shf_snprintf(buf, sizeof(buf), "Done (%d)",
1597				    exitstatus);
1598			break;
1599		}
1600		case PSIGNALLED: {
1601			int termsig = WTERMSIG(p->status);
1602#ifdef WCOREDUMP
1603			if (WCOREDUMP(p->status))
1604				coredumped = true;
1605#endif
1606			/*
1607			 * kludge for not reporting 'normal termination
1608			 * signals' (i.e. SIGINT, SIGPIPE)
1609			 */
1610			if (how == JP_SHORT &&
1611#ifdef WCOREDUMP
1612			    !coredumped &&
1613#endif
1614			    (termsig == SIGINT || termsig == SIGPIPE)) {
1615				buf[0] = '\0';
1616			} else
1617				strlcpy(buf, termsig > 0 && termsig < ksh_NSIG ?
1618				    sigtraps[termsig].mess : "Signalled",
1619				    sizeof(buf));
1620			break;
1621		}
1622		default:
1623			buf[0] = '\0';
1624		}
1625
1626		if (how != JP_SHORT) {
1627			if (p == j->proc_list)
1628				shf_fprintf(shf, "[%d] %c ", j->job, jobchar);
1629			else
1630				shf_puts(filler, shf);
1631		}
1632
1633		if (how == JP_LONG)
1634			shf_fprintf(shf, "%5d ", (int)p->pid);
1635
1636		if (how == JP_SHORT) {
1637			if (buf[0]) {
1638				output = 1;
1639#ifdef WCOREDUMP
1640				shf_fprintf(shf, "%s%s ",
1641				    buf, coredumped ? " (core dumped)" : null);
1642#else
1643				shf_puts(buf, shf);
1644				shf_putchar(' ', shf);
1645#endif
1646			}
1647		} else {
1648			output = 1;
1649			shf_fprintf(shf, "%-20s %s%s%s", buf, p->command,
1650			    p->next ? "|" : null,
1651#ifdef WCOREDUMP
1652			    coredumped ? " (core dumped)" :
1653#endif
1654			     null);
1655		}
1656
1657		state = p->state;
1658		status = p->status;
1659		p = p->next;
1660		while (p && p->state == state && p->status == status) {
1661			if (how == JP_LONG)
1662				shf_fprintf(shf, "%s%5d %-20s %s%s", filler,
1663				    (int)p->pid, T1space, p->command,
1664				    p->next ? "|" : null);
1665			else if (how == JP_MEDIUM)
1666				shf_fprintf(shf, Tf__ss, p->command,
1667				    p->next ? "|" : null);
1668			p = p->next;
1669		}
1670	}
1671	if (output)
1672		shf_putc('\n', shf);
1673}
1674
1675/*
1676 * Convert % sequence to job
1677 *
1678 * If jobs are compiled in then this routine expects sigchld to be blocked.
1679 */
1680static Job *
1681j_lookup(const char *cp, int *ecodep)
1682{
1683	Job *j, *last_match;
1684	Proc *p;
1685	size_t len;
1686	int job = 0;
1687
1688	if (ctype(*cp, C_DIGIT) && getn(cp, &job)) {
1689		/* Look for last_proc->pid (what $! returns) first... */
1690		for (j = job_list; j != NULL; j = j->next)
1691			if (j->last_proc && j->last_proc->pid == job)
1692				return (j);
1693		/*
1694		 * ...then look for process group (this is non-POSIX,
1695		 * but should not break anything
1696		 */
1697		for (j = job_list; j != NULL; j = j->next)
1698			if (j->pgrp && j->pgrp == job)
1699				return (j);
1700		goto j_lookup_nosuch;
1701	}
1702	if (*cp != '%') {
1703 j_lookup_invalid:
1704		if (ecodep)
1705			*ecodep = JL_INVALID;
1706		return (NULL);
1707	}
1708	switch (*++cp) {
1709	case '\0': /* non-standard */
1710	case '+':
1711	case '%':
1712		if (job_list != NULL)
1713			return (job_list);
1714		break;
1715
1716	case '-':
1717		if (job_list != NULL && job_list->next)
1718			return (job_list->next);
1719		break;
1720
1721	case '0': case '1': case '2': case '3': case '4':
1722	case '5': case '6': case '7': case '8': case '9':
1723		if (!getn(cp, &job))
1724			goto j_lookup_invalid;
1725		for (j = job_list; j != NULL; j = j->next)
1726			if (j->job == job)
1727				return (j);
1728		break;
1729
1730	/* %?string */
1731	case '?':
1732		last_match = NULL;
1733		for (j = job_list; j != NULL; j = j->next)
1734			for (p = j->proc_list; p != NULL; p = p->next)
1735				if (strstr(p->command, cp+1) != NULL) {
1736					if (last_match) {
1737						if (ecodep)
1738							*ecodep = JL_AMBIG;
1739						return (NULL);
1740					}
1741					last_match = j;
1742				}
1743		if (last_match)
1744			return (last_match);
1745		break;
1746
1747	/* %string */
1748	default:
1749		len = strlen(cp);
1750		last_match = NULL;
1751		for (j = job_list; j != NULL; j = j->next)
1752			if (strncmp(cp, j->proc_list->command, len) == 0) {
1753				if (last_match) {
1754					if (ecodep)
1755						*ecodep = JL_AMBIG;
1756					return (NULL);
1757				}
1758				last_match = j;
1759			}
1760		if (last_match)
1761			return (last_match);
1762		break;
1763	}
1764 j_lookup_nosuch:
1765	if (ecodep)
1766		*ecodep = JL_NOSUCH;
1767	return (NULL);
1768}
1769
1770static Job	*free_jobs;
1771static Proc	*free_procs;
1772
1773/*
1774 * allocate a new job and fill in the job number.
1775 *
1776 * If jobs are compiled in then this routine expects sigchld to be blocked.
1777 */
1778static Job *
1779new_job(void)
1780{
1781	int i;
1782	Job *newj, *j;
1783
1784	if (free_jobs != NULL) {
1785		newj = free_jobs;
1786		free_jobs = free_jobs->next;
1787	} else
1788		newj = alloc(sizeof(Job), APERM);
1789
1790	/* brute force method */
1791	for (i = 1; ; i++) {
1792		for (j = job_list; j && j->job != i; j = j->next)
1793			;
1794		if (j == NULL)
1795			break;
1796	}
1797	newj->job = i;
1798
1799	return (newj);
1800}
1801
1802/*
1803 * Allocate new process struct
1804 *
1805 * If jobs are compiled in then this routine expects sigchld to be blocked.
1806 */
1807static Proc *
1808new_proc(void)
1809{
1810	Proc *p;
1811
1812	if (free_procs != NULL) {
1813		p = free_procs;
1814		free_procs = free_procs->next;
1815	} else
1816		p = alloc(sizeof(Proc), APERM);
1817
1818	return (p);
1819}
1820
1821/*
1822 * Take job out of job_list and put old structures into free list.
1823 * Keeps nzombies, last_job and async_job up to date.
1824 *
1825 * If jobs are compiled in then this routine expects sigchld to be blocked.
1826 */
1827static void
1828remove_job(Job *j, const char *where)
1829{
1830	Proc *p, *tmp;
1831	Job **prev, *curr;
1832
1833	prev = &job_list;
1834	curr = job_list;
1835	while (curr && curr != j) {
1836		prev = &curr->next;
1837		curr = *prev;
1838	}
1839	if (curr != j) {
1840		internal_warningf("remove_job: job %s (%s)", Tnot_found, where);
1841		return;
1842	}
1843	*prev = curr->next;
1844
1845	/* free up proc structures */
1846	for (p = j->proc_list; p != NULL; ) {
1847		tmp = p;
1848		p = p->next;
1849		tmp->next = free_procs;
1850		free_procs = tmp;
1851	}
1852
1853	if ((j->flags & JF_ZOMBIE) && j->ppid == procpid)
1854		--nzombie;
1855	j->next = free_jobs;
1856	free_jobs = j;
1857
1858	if (j == last_job)
1859		last_job = NULL;
1860	if (j == async_job)
1861		async_job = NULL;
1862}
1863
1864/*
1865 * put j in a particular location (taking it out job_list if it is there
1866 * already)
1867 *
1868 * If jobs are compiled in then this routine expects sigchld to be blocked.
1869 */
1870static void
1871put_job(Job *j, int where)
1872{
1873	Job **prev, *curr;
1874
1875	/* Remove job from list (if there) */
1876	prev = &job_list;
1877	curr = job_list;
1878	while (curr && curr != j) {
1879		prev = &curr->next;
1880		curr = *prev;
1881	}
1882	if (curr == j)
1883		*prev = curr->next;
1884
1885	switch (where) {
1886	case PJ_ON_FRONT:
1887		j->next = job_list;
1888		job_list = j;
1889		break;
1890
1891	case PJ_PAST_STOPPED:
1892		prev = &job_list;
1893		curr = job_list;
1894		for (; curr && curr->state == PSTOPPED; prev = &curr->next,
1895		    curr = *prev)
1896			;
1897		j->next = curr;
1898		*prev = j;
1899		break;
1900	}
1901}
1902
1903/*
1904 * nuke a job (called when unable to start full job).
1905 *
1906 * If jobs are compiled in then this routine expects sigchld to be blocked.
1907 */
1908static int
1909kill_job(Job *j, int sig)
1910{
1911	Proc *p;
1912	int rval = 0;
1913
1914	for (p = j->proc_list; p != NULL; p = p->next)
1915		if (p->pid != 0)
1916			if (kill(p->pid, sig) < 0)
1917				rval = -1;
1918	return (rval);
1919}
1920
1921static void
1922tty_init_talking(void)
1923{
1924	switch (tty_init_fd()) {
1925	case 0:
1926		break;
1927	case 1:
1928#ifndef MKSH_DISABLE_TTY_WARNING
1929		warningf(false, Tf_sD_s_sD_s,
1930		    "No controlling tty", Topen, T_devtty, cstrerror(errno));
1931#endif
1932		break;
1933	case 2:
1934#ifndef MKSH_DISABLE_TTY_WARNING
1935		warningf(false, Tf_sD_s_s, Tcant_find, Ttty_fd,
1936		    cstrerror(errno));
1937#endif
1938		break;
1939	case 3:
1940		warningf(false, Tf_ssfaileds, "j_ttyinit",
1941		    Ttty_fd_dupof, cstrerror(errno));
1942		break;
1943	case 4:
1944		warningf(false, Tf_sD_sD_s, "j_ttyinit",
1945		    "can't set close-on-exec flag", cstrerror(errno));
1946		break;
1947	}
1948}
1949
1950static void
1951tty_init_state(void)
1952{
1953	if (tty_fd >= 0) {
1954		mksh_tcget(tty_fd, &tty_state);
1955		tty_hasstate = true;
1956	}
1957}
1958