xref: /netbsd-src/bin/csh/proc.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*-
2  * Copyright (c) 1980, 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*static char sccsid[] = "from: @(#)proc.c	5.22 (Berkeley) 6/14/91";*/
36 static char rcsid[] = "$Id: proc.c,v 1.4 1993/08/01 19:00:33 mycroft Exp $";
37 #endif /* not lint */
38 
39 #include <sys/types.h>
40 #include <sys/wait.h>
41 #include <errno.h>
42 #include <unistd.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #if __STDC__
46 # include <stdarg.h>
47 #else
48 # include <varargs.h>
49 #endif
50 
51 #include "csh.h"
52 #include "dir.h"
53 #include "proc.h"
54 #include "extern.h"
55 
56 #define BIGINDEX	9	/* largest desirable job index */
57 
58 static struct rusage zru;
59 
60 static void	 pflushall __P((void));
61 static void	 pflush __P((struct process *));
62 static void	 pclrcurr __P((struct process *));
63 static void	 padd __P((struct command *));
64 static int	 pprint __P((struct process *, int));
65 static void	 ptprint __P((struct process *));
66 static void	 pads __P((Char *));
67 static void	 pkill __P((Char **v, int));
68 static struct	process
69 		*pgetcurr __P((struct process *));
70 static void	 okpcntl __P((void));
71 
72 /*
73  * pchild - called at interrupt level by the SIGCHLD signal
74  *	indicating that at least one child has terminated or stopped
75  *	thus at least one wait system call will definitely return a
76  *	childs status.  Top level routines (like pwait) must be sure
77  *	to mask interrupts when playing with the proclist data structures!
78  */
79 /* ARGUSED */
80 void
81 pchild(notused)
82 	int notused;
83 {
84     register struct process *pp;
85     register struct process *fp;
86     register int pid;
87     extern int insource;
88     union wait w;
89     int     jobflags;
90     struct rusage ru;
91 
92 loop:
93     errno = 0;			/* reset, just in case */
94     pid = wait3(&w.w_status,
95        (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), &ru);
96 
97     if (pid <= 0) {
98 	if (errno == EINTR) {
99 	    errno = 0;
100 	    goto loop;
101 	}
102 	pnoprocesses = pid == -1;
103 	return;
104     }
105     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next)
106 	if (pid == pp->p_pid)
107 	    goto found;
108     goto loop;
109 found:
110     if (pid == atoi(short2str(value(STRchild))))
111 	unsetv(STRchild);
112     pp->p_flags &= ~(PRUNNING | PSTOPPED | PREPORTED);
113     if (WIFSTOPPED(w)) {
114 	pp->p_flags |= PSTOPPED;
115 	pp->p_reason = w.w_stopsig;
116     }
117     else {
118 	if (pp->p_flags & (PTIME | PPTIME) || adrof(STRtime))
119 	    (void) gettimeofday(&pp->p_etime, NULL);
120 
121 	pp->p_rusage = ru;
122 	if (WIFSIGNALED(w)) {
123 	    if (w.w_termsig == SIGINT)
124 		pp->p_flags |= PINTERRUPTED;
125 	    else
126 		pp->p_flags |= PSIGNALED;
127 	    if (w.w_coredump)
128 		pp->p_flags |= PDUMPED;
129 	    pp->p_reason = w.w_termsig;
130 	}
131 	else {
132 	    pp->p_reason = w.w_retcode;
133 	    if (pp->p_reason != 0)
134 		pp->p_flags |= PAEXITED;
135 	    else
136 		pp->p_flags |= PNEXITED;
137 	}
138     }
139     jobflags = 0;
140     fp = pp;
141     do {
142 	if ((fp->p_flags & (PPTIME | PRUNNING | PSTOPPED)) == 0 &&
143 	    !child && adrof(STRtime) &&
144 	    fp->p_rusage.ru_utime.tv_sec + fp->p_rusage.ru_stime.tv_sec
145 	    >= atoi(short2str(value(STRtime))))
146 	    fp->p_flags |= PTIME;
147 	jobflags |= fp->p_flags;
148     } while ((fp = fp->p_friends) != pp);
149     pp->p_flags &= ~PFOREGND;
150     if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
151 	pp->p_flags &= ~PPTIME;
152 	pp->p_flags |= PTIME;
153     }
154     if ((jobflags & (PRUNNING | PREPORTED)) == 0) {
155 	fp = pp;
156 	do {
157 	    if (fp->p_flags & PSTOPPED)
158 		fp->p_flags |= PREPORTED;
159 	} while ((fp = fp->p_friends) != pp);
160 	while (fp->p_pid != fp->p_jobid)
161 	    fp = fp->p_friends;
162 	if (jobflags & PSTOPPED) {
163 	    if (pcurrent && pcurrent != fp)
164 		pprevious = pcurrent;
165 	    pcurrent = fp;
166 	}
167 	else
168 	    pclrcurr(fp);
169 	if (jobflags & PFOREGND) {
170 	    if (jobflags & (PSIGNALED | PSTOPPED | PPTIME) ||
171 #ifdef IIASA
172 		jobflags & PAEXITED ||
173 #endif
174 		!eq(dcwd->di_name, fp->p_cwd->di_name)) {
175 		;		/* print in pjwait */
176 	    }
177 	    /* PWP: print a newline after ^C */
178 	    else if (jobflags & PINTERRUPTED)
179 		xputchar('\r' | QUOTE), xputchar('\n');
180 	}
181 	else {
182 	    if (jobflags & PNOTIFY || adrof(STRnotify)) {
183 		xputchar('\r' | QUOTE), xputchar('\n');
184 		(void) pprint(pp, NUMBER | NAME | REASON);
185 		if ((jobflags & PSTOPPED) == 0)
186 		    pflush(pp);
187 	    }
188 	    else {
189 		fp->p_flags |= PNEEDNOTE;
190 		neednote++;
191 	    }
192 	}
193     }
194     goto loop;
195 }
196 
197 void
198 pnote()
199 {
200     register struct process *pp;
201     int     flags;
202     sigset_t omask;
203 
204     neednote = 0;
205     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next) {
206 	if (pp->p_flags & PNEEDNOTE) {
207 	    omask = sigblock(sigmask(SIGCHLD));
208 	    pp->p_flags &= ~PNEEDNOTE;
209 	    flags = pprint(pp, NUMBER | NAME | REASON);
210 	    if ((flags & (PRUNNING | PSTOPPED)) == 0)
211 		pflush(pp);
212 	    (void) sigsetmask(omask);
213 	}
214     }
215 }
216 
217 /*
218  * pwait - wait for current job to terminate, maintaining integrity
219  *	of current and previous job indicators.
220  */
221 void
222 pwait()
223 {
224     register struct process *fp, *pp;
225     sigset_t omask;
226 
227     /*
228      * Here's where dead procs get flushed.
229      */
230     omask = sigblock(sigmask(SIGCHLD));
231     for (pp = (fp = &proclist)->p_next; pp != NULL; pp = (fp = pp)->p_next)
232 	if (pp->p_pid == 0) {
233 	    fp->p_next = pp->p_next;
234 	    xfree((ptr_t) pp->p_command);
235 	    if (pp->p_cwd && --pp->p_cwd->di_count == 0)
236 		if (pp->p_cwd->di_next == 0)
237 		    dfree(pp->p_cwd);
238 	    xfree((ptr_t) pp);
239 	    pp = fp;
240 	}
241     (void) sigsetmask(omask);
242     pjwait(pcurrjob);
243 }
244 
245 
246 /*
247  * pjwait - wait for a job to finish or become stopped
248  *	It is assumed to be in the foreground state (PFOREGND)
249  */
250 void
251 pjwait(pp)
252     register struct process *pp;
253 {
254     register struct process *fp;
255     int     jobflags, reason;
256     sigset_t omask;
257 
258     while (pp->p_pid != pp->p_jobid)
259 	pp = pp->p_friends;
260     fp = pp;
261 
262     do {
263 	if ((fp->p_flags & (PFOREGND | PRUNNING)) == PRUNNING)
264 	    xprintf("BUG: waiting for background job!\n");
265     } while ((fp = fp->p_friends) != pp);
266     /*
267      * Now keep pausing as long as we are not interrupted (SIGINT), and the
268      * target process, or any of its friends, are running
269      */
270     fp = pp;
271     omask = sigblock(sigmask(SIGCHLD));
272     for (;;) {
273 	(void) sigblock(sigmask(SIGCHLD));
274 	jobflags = 0;
275 	do
276 	    jobflags |= fp->p_flags;
277 	while ((fp = (fp->p_friends)) != pp);
278 	if ((jobflags & PRUNNING) == 0)
279 	    break;
280 #ifdef JOBDEBUG
281 	xprintf("starting to sigpause for  SIGCHLD on %d\n", fp->p_pid);
282 #endif				/* JOBDEBUG */
283 	(void) sigpause(omask & ~sigmask(SIGCHLD));
284     }
285     (void) sigsetmask(omask);
286     if (tpgrp > 0)		/* get tty back */
287 	(void) tcsetpgrp(FSHTTY, tpgrp);
288     if ((jobflags & (PSIGNALED | PSTOPPED | PTIME)) ||
289 	!eq(dcwd->di_name, fp->p_cwd->di_name)) {
290 	if (jobflags & PSTOPPED) {
291 	    xprintf("\n");
292 	    if (adrof(STRlistjobs)) {
293 		Char   *jobcommand[3];
294 
295 		jobcommand[0] = STRjobs;
296 		if (eq(value(STRlistjobs), STRlong))
297 		    jobcommand[1] = STRml;
298 		else
299 		    jobcommand[1] = NULL;
300 		jobcommand[2] = NULL;
301 
302 		dojobs(jobcommand);
303 		(void) pprint(pp, SHELLDIR);
304 	    }
305 	    else
306 		(void) pprint(pp, AREASON | SHELLDIR);
307 	}
308 	else
309 	    (void) pprint(pp, AREASON | SHELLDIR);
310     }
311     if ((jobflags & (PINTERRUPTED | PSTOPPED)) && setintr &&
312 	(!gointr || !eq(gointr, STRminus))) {
313 	if ((jobflags & PSTOPPED) == 0)
314 	    pflush(pp);
315 	pintr1(0);
316 	/* NOTREACHED */
317     }
318     reason = 0;
319     fp = pp;
320     do {
321 	if (fp->p_reason)
322 	    reason = fp->p_flags & (PSIGNALED | PINTERRUPTED) ?
323 		fp->p_reason | META : fp->p_reason;
324     } while ((fp = fp->p_friends) != pp);
325     if ((reason != 0) && (adrof(STRprintexitvalue)))
326 	xprintf("Exit %d\n", reason);
327     set(STRstatus, putn(reason));
328     if (reason && exiterr)
329 	exitstat();
330     pflush(pp);
331 }
332 
333 /*
334  * dowait - wait for all processes to finish
335  */
336 void
337 dowait()
338 {
339     register struct process *pp;
340     sigset_t omask;
341 
342     pjobs++;
343     omask = sigblock(sigmask(SIGCHLD));
344 loop:
345     for (pp = proclist.p_next; pp; pp = pp->p_next)
346 	if (pp->p_pid &&	/* pp->p_pid == pp->p_jobid && */
347 	    pp->p_flags & PRUNNING) {
348 	    (void) sigpause((sigset_t) 0);
349 	    goto loop;
350 	}
351     (void) sigsetmask(omask);
352     pjobs = 0;
353 }
354 
355 /*
356  * pflushall - flush all jobs from list (e.g. at fork())
357  */
358 static void
359 pflushall()
360 {
361     register struct process *pp;
362 
363     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next)
364 	if (pp->p_pid)
365 	    pflush(pp);
366 }
367 
368 /*
369  * pflush - flag all process structures in the same job as the
370  *	the argument process for deletion.  The actual free of the
371  *	space is not done here since pflush is called at interrupt level.
372  */
373 static void
374 pflush(pp)
375     register struct process *pp;
376 {
377     register struct process *np;
378     register int idx;
379 
380     if (pp->p_pid == 0) {
381 	xprintf("BUG: process flushed twice");
382 	return;
383     }
384     while (pp->p_pid != pp->p_jobid)
385 	pp = pp->p_friends;
386     pclrcurr(pp);
387     if (pp == pcurrjob)
388 	pcurrjob = 0;
389     idx = pp->p_index;
390     np = pp;
391     do {
392 	np->p_index = np->p_pid = 0;
393 	np->p_flags &= ~PNEEDNOTE;
394     } while ((np = np->p_friends) != pp);
395     if (idx == pmaxindex) {
396 	for (np = proclist.p_next, idx = 0; np; np = np->p_next)
397 	    if (np->p_index > idx)
398 		idx = np->p_index;
399 	pmaxindex = idx;
400     }
401 }
402 
403 /*
404  * pclrcurr - make sure the given job is not the current or previous job;
405  *	pp MUST be the job leader
406  */
407 static void
408 pclrcurr(pp)
409     register struct process *pp;
410 {
411 
412     if (pp == pcurrent)
413 	if (pprevious != NULL) {
414 	    pcurrent = pprevious;
415 	    pprevious = pgetcurr(pp);
416 	}
417 	else {
418 	    pcurrent = pgetcurr(pp);
419 	    pprevious = pgetcurr(pp);
420 	}
421     else if (pp == pprevious)
422 	pprevious = pgetcurr(pp);
423 }
424 
425 /* +4 here is 1 for '\0', 1 ea for << >& >> */
426 static Char command[PMAXLEN + 4];
427 static int cmdlen;
428 static Char *cmdp;
429 
430 /*
431  * palloc - allocate a process structure and fill it up.
432  *	an important assumption is made that the process is running.
433  */
434 void
435 palloc(pid, t)
436     int     pid;
437     register struct command *t;
438 {
439     register struct process *pp;
440     int     i;
441 
442     pp = (struct process *) xcalloc(1, (size_t) sizeof(struct process));
443     pp->p_pid = pid;
444     pp->p_flags = t->t_dflg & F_AMPERSAND ? PRUNNING : PRUNNING | PFOREGND;
445     if (t->t_dflg & F_TIME)
446 	pp->p_flags |= PPTIME;
447     cmdp = command;
448     cmdlen = 0;
449     padd(t);
450     *cmdp++ = 0;
451     if (t->t_dflg & F_PIPEOUT) {
452 	pp->p_flags |= PPOU;
453 	if (t->t_dflg & F_STDERR)
454 	    pp->p_flags |= PDIAG;
455     }
456     pp->p_command = Strsave(command);
457     if (pcurrjob) {
458 	struct process *fp;
459 
460 	/* careful here with interrupt level */
461 	pp->p_cwd = 0;
462 	pp->p_index = pcurrjob->p_index;
463 	pp->p_friends = pcurrjob;
464 	pp->p_jobid = pcurrjob->p_pid;
465 	for (fp = pcurrjob; fp->p_friends != pcurrjob; fp = fp->p_friends);
466 	fp->p_friends = pp;
467     }
468     else {
469 	pcurrjob = pp;
470 	pp->p_jobid = pid;
471 	pp->p_friends = pp;
472 	pp->p_cwd = dcwd;
473 	dcwd->di_count++;
474 	if (pmaxindex < BIGINDEX)
475 	    pp->p_index = ++pmaxindex;
476 	else {
477 	    struct process *np;
478 
479 	    for (i = 1;; i++) {
480 		for (np = proclist.p_next; np; np = np->p_next)
481 		    if (np->p_index == i)
482 			goto tryagain;
483 		pp->p_index = i;
484 		if (i > pmaxindex)
485 		    pmaxindex = i;
486 		break;
487 	tryagain:;
488 	    }
489 	}
490 	if (pcurrent == NULL)
491 	    pcurrent = pp;
492 	else if (pprevious == NULL)
493 	    pprevious = pp;
494     }
495     pp->p_next = proclist.p_next;
496     proclist.p_next = pp;
497     (void) gettimeofday(&pp->p_btime, NULL);
498 }
499 
500 static void
501 padd(t)
502     register struct command *t;
503 {
504     Char  **argp;
505 
506     if (t == 0)
507 	return;
508     switch (t->t_dtyp) {
509 
510     case NODE_PAREN:
511 	pads(STRLparensp);
512 	padd(t->t_dspr);
513 	pads(STRspRparen);
514 	break;
515 
516     case NODE_COMMAND:
517 	for (argp = t->t_dcom; *argp; argp++) {
518 	    pads(*argp);
519 	    if (argp[1])
520 		pads(STRspace);
521 	}
522 	break;
523 
524     case NODE_OR:
525     case NODE_AND:
526     case NODE_PIPE:
527     case NODE_LIST:
528 	padd(t->t_dcar);
529 	switch (t->t_dtyp) {
530 	case NODE_OR:
531 	    pads(STRspor2sp);
532 	    break;
533 	case NODE_AND:
534 	    pads(STRspand2sp);
535 	    break;
536 	case NODE_PIPE:
537 	    pads(STRsporsp);
538 	    break;
539 	case NODE_LIST:
540 	    pads(STRsemisp);
541 	    break;
542 	}
543 	padd(t->t_dcdr);
544 	return;
545     }
546     if ((t->t_dflg & F_PIPEIN) == 0 && t->t_dlef) {
547 	pads((t->t_dflg & F_READ) ? STRspLarrow2sp : STRspLarrowsp);
548 	pads(t->t_dlef);
549     }
550     if ((t->t_dflg & F_PIPEOUT) == 0 && t->t_drit) {
551 	pads((t->t_dflg & F_APPEND) ? STRspRarrow2 : STRspRarrow);
552 	if (t->t_dflg & F_STDERR)
553 	    pads(STRand);
554 	pads(STRspace);
555 	pads(t->t_drit);
556     }
557 }
558 
559 static void
560 pads(cp)
561     Char   *cp;
562 {
563     register int i;
564 
565     /*
566      * Avoid the Quoted Space alias hack! Reported by:
567      * sam@john-bigboote.ICS.UCI.EDU (Sam Horrocks)
568      */
569     if (cp[0] == STRQNULL[0])
570 	cp++;
571 
572     i = Strlen(cp);
573 
574     if (cmdlen >= PMAXLEN)
575 	return;
576     if (cmdlen + i >= PMAXLEN) {
577 	(void) Strcpy(cmdp, STRsp3dots);
578 	cmdlen = PMAXLEN;
579 	cmdp += 4;
580 	return;
581     }
582     (void) Strcpy(cmdp, cp);
583     cmdp += i;
584     cmdlen += i;
585 }
586 
587 /*
588  * psavejob - temporarily save the current job on a one level stack
589  *	so another job can be created.  Used for { } in exp6
590  *	and `` in globbing.
591  */
592 void
593 psavejob()
594 {
595 
596     pholdjob = pcurrjob;
597     pcurrjob = NULL;
598 }
599 
600 /*
601  * prestjob - opposite of psavejob.  This may be missed if we are interrupted
602  *	somewhere, but pendjob cleans up anyway.
603  */
604 void
605 prestjob()
606 {
607 
608     pcurrjob = pholdjob;
609     pholdjob = NULL;
610 }
611 
612 /*
613  * pendjob - indicate that a job (set of commands) has been completed
614  *	or is about to begin.
615  */
616 void
617 pendjob()
618 {
619     register struct process *pp, *tp;
620 
621     if (pcurrjob && (pcurrjob->p_flags & (PFOREGND | PSTOPPED)) == 0) {
622 	pp = pcurrjob;
623 	while (pp->p_pid != pp->p_jobid)
624 	    pp = pp->p_friends;
625 	xprintf("[%d]", pp->p_index);
626 	tp = pp;
627 	do {
628 	    xprintf(" %d", pp->p_pid);
629 	    pp = pp->p_friends;
630 	} while (pp != tp);
631 	xprintf("\n");
632     }
633     pholdjob = pcurrjob = 0;
634 }
635 
636 /*
637  * pprint - print a job
638  */
639 static int
640 pprint(pp, flag)
641     register struct process *pp;
642     bool    flag;
643 {
644     register status, reason;
645     struct process *tp;
646     extern char *linp, linbuf[];
647     int     jobflags, pstatus;
648     char   *format;
649 
650     while (pp->p_pid != pp->p_jobid)
651 	pp = pp->p_friends;
652     if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
653 	pp->p_flags &= ~PPTIME;
654 	pp->p_flags |= PTIME;
655     }
656     tp = pp;
657     status = reason = -1;
658     jobflags = 0;
659     do {
660 	jobflags |= pp->p_flags;
661 	pstatus = pp->p_flags & PALLSTATES;
662 	if (tp != pp && linp != linbuf && !(flag & FANCY) &&
663 	    (pstatus == status && pp->p_reason == reason ||
664 	     !(flag & REASON)))
665 	    xprintf(" ");
666 	else {
667 	    if (tp != pp && linp != linbuf)
668 		xprintf("\n");
669 	    if (flag & NUMBER)
670 		if (pp == tp)
671 		    xprintf("[%d]%s %c ", pp->p_index,
672 			    pp->p_index < 10 ? " " : "",
673 			    pp == pcurrent ? '+' :
674 			    (pp == pprevious ? '-' : ' '));
675 		else
676 		    xprintf("       ");
677 	    if (flag & FANCY) {
678 		xprintf("%5d ", pp->p_pid);
679 	    }
680 	    if (flag & (REASON | AREASON)) {
681 		if (flag & NAME)
682 		    format = "%-23s";
683 		else
684 		    format = "%s";
685 		if (pstatus == status)
686 		    if (pp->p_reason == reason) {
687 			xprintf(format, "");
688 			goto prcomd;
689 		    }
690 		    else
691 			reason = pp->p_reason;
692 		else {
693 		    status = pstatus;
694 		    reason = pp->p_reason;
695 		}
696 		switch (status) {
697 
698 		case PRUNNING:
699 		    xprintf(format, "Running ");
700 		    break;
701 
702 		case PINTERRUPTED:
703 		case PSTOPPED:
704 		case PSIGNALED:
705 		    if ((flag & REASON) ||
706 			((flag & AREASON) && reason != SIGINT
707 			 && reason != SIGPIPE))
708 			xprintf(format, mesg[pp->p_reason].pname);
709 		    break;
710 
711 		case PNEXITED:
712 		case PAEXITED:
713 		    if (flag & REASON)
714 			if (pp->p_reason)
715 			    xprintf("Exit %-18d", pp->p_reason);
716 			else
717 			    xprintf(format, "Done");
718 		    break;
719 
720 		default:
721 		    xprintf("BUG: status=%-9o", status);
722 		}
723 	    }
724 	}
725 prcomd:
726 	if (flag & NAME) {
727 	    xprintf("%s", short2str(pp->p_command));
728 	    if (pp->p_flags & PPOU)
729 		xprintf(" |");
730 	    if (pp->p_flags & PDIAG)
731 		xprintf("&");
732 	}
733 	if (flag & (REASON | AREASON) && pp->p_flags & PDUMPED)
734 	    xprintf(" (core dumped)");
735 	if (tp == pp->p_friends) {
736 	    if (flag & AMPERSAND)
737 		xprintf(" &");
738 	    if (flag & JOBDIR &&
739 		!eq(tp->p_cwd->di_name, dcwd->di_name)) {
740 		xprintf(" (wd: ");
741 		dtildepr(value(STRhome), tp->p_cwd->di_name);
742 		xprintf(")");
743 	    }
744 	}
745 	if (pp->p_flags & PPTIME && !(status & (PSTOPPED | PRUNNING))) {
746 	    if (linp != linbuf)
747 		xprintf("\n\t");
748 	    prusage(&zru, &pp->p_rusage, &pp->p_etime,
749 		    &pp->p_btime);
750 	}
751 	if (tp == pp->p_friends) {
752 	    if (linp != linbuf)
753 		xprintf("\n");
754 	    if (flag & SHELLDIR && !eq(tp->p_cwd->di_name, dcwd->di_name)) {
755 		xprintf("(wd now: ");
756 		dtildepr(value(STRhome), dcwd->di_name);
757 		xprintf(")\n");
758 	    }
759 	}
760     } while ((pp = pp->p_friends) != tp);
761     if (jobflags & PTIME && (jobflags & (PSTOPPED | PRUNNING)) == 0) {
762 	if (jobflags & NUMBER)
763 	    xprintf("       ");
764 	ptprint(tp);
765     }
766     return (jobflags);
767 }
768 
769 static void
770 ptprint(tp)
771     register struct process *tp;
772 {
773     struct timeval tetime, diff;
774     static struct timeval ztime;
775     struct rusage ru;
776     static struct rusage zru;
777     register struct process *pp = tp;
778 
779     ru = zru;
780     tetime = ztime;
781     do {
782 	ruadd(&ru, &pp->p_rusage);
783 	tvsub(&diff, &pp->p_etime, &pp->p_btime);
784 	if (timercmp(&diff, &tetime, >))
785 	    tetime = diff;
786     } while ((pp = pp->p_friends) != tp);
787     prusage(&zru, &ru, &tetime, &ztime);
788 }
789 
790 /*
791  * dojobs - print all jobs
792  */
793 void
794 dojobs(v)
795     Char  **v;
796 {
797     register struct process *pp;
798     register int flag = NUMBER | NAME | REASON;
799     int     i;
800 
801     if (chkstop)
802 	chkstop = 2;
803     if (*++v) {
804 	if (v[1] || !eq(*v, STRml))
805 	    stderror(ERR_JOBS);
806 	flag |= FANCY | JOBDIR;
807     }
808     for (i = 1; i <= pmaxindex; i++)
809 	for (pp = proclist.p_next; pp; pp = pp->p_next)
810 	    if (pp->p_index == i && pp->p_pid == pp->p_jobid) {
811 		pp->p_flags &= ~PNEEDNOTE;
812 		if (!(pprint(pp, flag) & (PRUNNING | PSTOPPED)))
813 		    pflush(pp);
814 		break;
815 	    }
816 }
817 
818 /*
819  * dofg - builtin - put the job into the foreground
820  */
821 void
822 dofg(v)
823     Char  **v;
824 {
825     register struct process *pp;
826 
827     okpcntl();
828     ++v;
829     do {
830 	pp = pfind(*v);
831 	pstart(pp, 1);
832 	pjwait(pp);
833     } while (*v && *++v);
834 }
835 
836 /*
837  * %... - builtin - put the job into the foreground
838  */
839 void
840 dofg1(v)
841     Char  **v;
842 {
843     register struct process *pp;
844 
845     okpcntl();
846     pp = pfind(v[0]);
847     pstart(pp, 1);
848     pjwait(pp);
849 }
850 
851 /*
852  * dobg - builtin - put the job into the background
853  */
854 void
855 dobg(v)
856     Char  **v;
857 {
858     register struct process *pp;
859 
860     okpcntl();
861     ++v;
862     do {
863 	pp = pfind(*v);
864 	pstart(pp, 0);
865     } while (*v && *++v);
866 }
867 
868 /*
869  * %... & - builtin - put the job into the background
870  */
871 void
872 dobg1(v)
873     Char  **v;
874 {
875     register struct process *pp;
876 
877     pp = pfind(v[0]);
878     pstart(pp, 0);
879 }
880 
881 /*
882  * dostop - builtin - stop the job
883  */
884 void
885 dostop(v)
886     Char  **v;
887 {
888     pkill(++v, SIGSTOP);
889 }
890 
891 /*
892  * dokill - builtin - superset of kill (1)
893  */
894 void
895 dokill(v)
896     Char  **v;
897 {
898     register int signum, len = 0;
899     register char *name;
900 
901     v++;
902     if (v[0] && v[0][0] == '-') {
903 	if (v[0][1] == 'l') {
904 	    for (signum = 1; signum <= NSIG; signum++) {
905 		if ((name = mesg[signum].iname) != NULL) {
906 		    len += strlen(name) + 1;
907 		    if (len >= 80 - 1) {
908 			xprintf("\n");
909 			len = strlen(name) + 1;
910 		    }
911 		    xprintf("%s ", name);
912 		}
913 	    }
914 	    xprintf("\n");
915 	    return;
916 	}
917 	if (Isdigit(v[0][1])) {
918 	    signum = atoi(short2str(v[0] + 1));
919 	    if (signum < 0 || signum > NSIG)
920 		stderror(ERR_NAME | ERR_BADSIG);
921 	}
922 	else {
923 	    for (signum = 1; signum <= NSIG; signum++)
924 		if (mesg[signum].iname &&
925 		    eq(&v[0][1], str2short(mesg[signum].iname)))
926 		    goto gotsig;
927 	    setname(short2str(&v[0][1]));
928 	    stderror(ERR_NAME | ERR_UNKSIG);
929 	}
930 gotsig:
931 	v++;
932     }
933     else
934 	signum = SIGTERM;
935     pkill(v, signum);
936 }
937 
938 static void
939 pkill(v, signum)
940     Char  **v;
941     int     signum;
942 {
943     register struct process *pp, *np;
944     register int jobflags = 0;
945     int     pid, err1 = 0;
946     sigset_t omask;
947     Char   *cp;
948 
949     omask = sigmask(SIGCHLD);
950     if (setintr)
951 	omask |= sigmask(SIGINT);
952     omask = sigblock(omask) & ~omask;
953     gflag = 0, tglob(v);
954     if (gflag) {
955 	v = globall(v);
956 	if (v == 0)
957 	    stderror(ERR_NAME | ERR_NOMATCH);
958     }
959     else {
960 	v = gargv = saveblk(v);
961 	trim(v);
962     }
963 
964     while (v && (cp = *v)) {
965 	if (*cp == '%') {
966 	    np = pp = pfind(cp);
967 	    do
968 		jobflags |= np->p_flags;
969 	    while ((np = np->p_friends) != pp);
970 	    switch (signum) {
971 
972 	    case SIGSTOP:
973 	    case SIGTSTP:
974 	    case SIGTTIN:
975 	    case SIGTTOU:
976 		if ((jobflags & PRUNNING) == 0) {
977 		    xprintf("%s: Already suspended\n", short2str(cp));
978 		    err1++;
979 		    goto cont;
980 		}
981 		break;
982 		/*
983 		 * suspend a process, kill -CONT %, then type jobs; the shell
984 		 * says it is suspended, but it is running; thanks jaap..
985 		 */
986 	    case SIGCONT:
987 		pstart(pp, 0);
988 		goto cont;
989 	    }
990 	    if (killpg((pid_t) pp->p_jobid, signum) < 0) {
991 		xprintf("%s: %s\n", short2str(cp), strerror(errno));
992 		err1++;
993 	    }
994 	    if (signum == SIGTERM || signum == SIGHUP)
995 		(void) killpg((pid_t) pp->p_jobid, SIGCONT);
996 	}
997 	else if (!(Isdigit(*cp) || *cp == '-'))
998 	    stderror(ERR_NAME | ERR_JOBARGS);
999 	else {
1000 	    pid = atoi(short2str(cp));
1001 	    if (kill((pid_t) pid, signum) < 0) {
1002 		xprintf("%d: %s\n", pid, strerror(errno));
1003 		err1++;
1004 		goto cont;
1005 	    }
1006 	    if (signum == SIGTERM || signum == SIGHUP)
1007 		(void) kill((pid_t) pid, SIGCONT);
1008 	}
1009 cont:
1010 	v++;
1011     }
1012     if (gargv)
1013 	blkfree(gargv), gargv = 0;
1014     (void) sigsetmask(omask);
1015     if (err1)
1016 	stderror(ERR_SILENT);
1017 }
1018 
1019 /*
1020  * pstart - start the job in foreground/background
1021  */
1022 void
1023 pstart(pp, foregnd)
1024     register struct process *pp;
1025     int     foregnd;
1026 {
1027     register struct process *np;
1028     sigset_t omask;
1029     long    jobflags = 0;
1030 
1031     omask = sigblock(sigmask(SIGCHLD));
1032     np = pp;
1033     do {
1034 	jobflags |= np->p_flags;
1035 	if (np->p_flags & (PRUNNING | PSTOPPED)) {
1036 	    np->p_flags |= PRUNNING;
1037 	    np->p_flags &= ~PSTOPPED;
1038 	    if (foregnd)
1039 		np->p_flags |= PFOREGND;
1040 	    else
1041 		np->p_flags &= ~PFOREGND;
1042 	}
1043     } while ((np = np->p_friends) != pp);
1044     if (!foregnd)
1045 	pclrcurr(pp);
1046     (void) pprint(pp, foregnd ? NAME | JOBDIR : NUMBER | NAME | AMPERSAND);
1047     if (foregnd)
1048 	(void) tcsetpgrp(FSHTTY, pp->p_jobid);
1049     if (jobflags & PSTOPPED)
1050 	(void) killpg((pid_t) pp->p_jobid, SIGCONT);
1051     (void) sigsetmask(omask);
1052 }
1053 
1054 void
1055 panystop(neednl)
1056     bool    neednl;
1057 {
1058     register struct process *pp;
1059 
1060     chkstop = 2;
1061     for (pp = proclist.p_next; pp; pp = pp->p_next)
1062 	if (pp->p_flags & PSTOPPED)
1063 	    stderror(ERR_STOPPED, neednl ? "\n" : "");
1064 }
1065 
1066 struct process *
1067 pfind(cp)
1068     Char   *cp;
1069 {
1070     register struct process *pp, *np;
1071 
1072     if (cp == 0 || cp[1] == 0 || eq(cp, STRcent2) || eq(cp, STRcentplus)) {
1073 	if (pcurrent == NULL)
1074 	    stderror(ERR_NAME | ERR_JOBCUR);
1075 	return (pcurrent);
1076     }
1077     if (eq(cp, STRcentminus) || eq(cp, STRcenthash)) {
1078 	if (pprevious == NULL)
1079 	    stderror(ERR_NAME | ERR_JOBPREV);
1080 	return (pprevious);
1081     }
1082     if (Isdigit(cp[1])) {
1083 	int     idx = atoi(short2str(cp + 1));
1084 
1085 	for (pp = proclist.p_next; pp; pp = pp->p_next)
1086 	    if (pp->p_index == idx && pp->p_pid == pp->p_jobid)
1087 		return (pp);
1088 	stderror(ERR_NAME | ERR_NOSUCHJOB);
1089     }
1090     np = NULL;
1091     for (pp = proclist.p_next; pp; pp = pp->p_next)
1092 	if (pp->p_pid == pp->p_jobid) {
1093 	    if (cp[1] == '?') {
1094 		register Char *dp;
1095 
1096 		for (dp = pp->p_command; *dp; dp++) {
1097 		    if (*dp != cp[2])
1098 			continue;
1099 		    if (prefix(cp + 2, dp))
1100 			goto match;
1101 		}
1102 	    }
1103 	    else if (prefix(cp + 1, pp->p_command)) {
1104 	match:
1105 		if (np)
1106 		    stderror(ERR_NAME | ERR_AMBIG);
1107 		np = pp;
1108 	    }
1109 	}
1110     if (np)
1111 	return (np);
1112     stderror(ERR_NAME | cp[1] == '?' ? ERR_JOBPAT : ERR_NOSUCHJOB);
1113     /* NOTREACHED */
1114     return (0);
1115 }
1116 
1117 
1118 /*
1119  * pgetcurr - find most recent job that is not pp, preferably stopped
1120  */
1121 static struct process *
1122 pgetcurr(pp)
1123     register struct process *pp;
1124 {
1125     register struct process *np;
1126     register struct process *xp = NULL;
1127 
1128     for (np = proclist.p_next; np; np = np->p_next)
1129 	if (np != pcurrent && np != pp && np->p_pid &&
1130 	    np->p_pid == np->p_jobid) {
1131 	    if (np->p_flags & PSTOPPED)
1132 		return (np);
1133 	    if (xp == NULL)
1134 		xp = np;
1135 	}
1136     return (xp);
1137 }
1138 
1139 /*
1140  * donotify - flag the job so as to report termination asynchronously
1141  */
1142 void
1143 donotify(v)
1144     Char  **v;
1145 {
1146     register struct process *pp;
1147 
1148     pp = pfind(*++v);
1149     pp->p_flags |= PNOTIFY;
1150 }
1151 
1152 /*
1153  * Do the fork and whatever should be done in the child side that
1154  * should not be done if we are not forking at all (like for simple builtin's)
1155  * Also do everything that needs any signals fiddled with in the parent side
1156  *
1157  * Wanttty tells whether process and/or tty pgrps are to be manipulated:
1158  *	-1:	leave tty alone; inherit pgrp from parent
1159  *	 0:	already have tty; manipulate process pgrps only
1160  *	 1:	want to claim tty; manipulate process and tty pgrps
1161  * It is usually just the value of tpgrp.
1162  */
1163 
1164 int
1165 pfork(t, wanttty)
1166     struct command *t;		/* command we are forking for */
1167     int     wanttty;
1168 {
1169     register int pid;
1170     bool    ignint = 0;
1171     int     pgrp;
1172     sigset_t omask;
1173 
1174     /*
1175      * A child will be uninterruptible only under very special conditions.
1176      * Remember that the semantics of '&' is implemented by disconnecting the
1177      * process from the tty so signals do not need to ignored just for '&'.
1178      * Thus signals are set to default action for children unless: we have had
1179      * an "onintr -" (then specifically ignored) we are not playing with
1180      * signals (inherit action)
1181      */
1182     if (setintr)
1183 	ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT))
1184 	    || (gointr && eq(gointr, STRminus));
1185     /*
1186      * Check for maximum nesting of 16 processes to avoid Forking loops
1187      */
1188     if (child == 16)
1189 	stderror(ERR_NESTING, 16);
1190     /*
1191      * Hold SIGCHLD until we have the process installed in our table.
1192      */
1193     omask = sigblock(sigmask(SIGCHLD));
1194     while ((pid = fork()) < 0)
1195 	if (setintr == 0)
1196 	    (void) sleep(FORKSLEEP);
1197 	else {
1198 	    (void) sigsetmask(omask);
1199 	    stderror(ERR_NOPROC);
1200 	}
1201     if (pid == 0) {
1202 	settimes();
1203 	pgrp = pcurrjob ? pcurrjob->p_jobid : getpid();
1204 	pflushall();
1205 	pcurrjob = NULL;
1206 	child++;
1207 	if (setintr) {
1208 	    setintr = 0;	/* until I think otherwise */
1209 	    /*
1210 	     * Children just get blown away on SIGINT, SIGQUIT unless "onintr
1211 	     * -" seen.
1212 	     */
1213 	    (void) signal(SIGINT, ignint ? SIG_IGN : SIG_DFL);
1214 	    (void) signal(SIGQUIT, ignint ? SIG_IGN : SIG_DFL);
1215 	    if (wanttty >= 0) {
1216 		/* make stoppable */
1217 		(void) signal(SIGTSTP, SIG_DFL);
1218 		(void) signal(SIGTTIN, SIG_DFL);
1219 		(void) signal(SIGTTOU, SIG_DFL);
1220 	    }
1221 	    (void) signal(SIGTERM, parterm);
1222 	}
1223 	else if (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT)) {
1224 	    (void) signal(SIGINT, SIG_IGN);
1225 	    (void) signal(SIGQUIT, SIG_IGN);
1226 	}
1227 	pgetty(wanttty, pgrp);
1228 	/*
1229 	 * Nohup and nice apply only to NODE_COMMAND's but it would be nice
1230 	 * (?!?) if you could say "nohup (foo;bar)" Then the parser would have
1231 	 * to know about nice/nohup/time
1232 	 */
1233 	if (t->t_dflg & F_NOHUP)
1234 	    (void) signal(SIGHUP, SIG_IGN);
1235 	if (t->t_dflg & F_NICE)
1236 	    (void) setpriority(PRIO_PROCESS, 0, t->t_nice);
1237     }
1238     else {
1239 	if (wanttty >= 0)
1240 	    (void) setpgid(pid, pcurrjob ? pcurrjob->p_jobid : pid);
1241 	palloc(pid, t);
1242 	(void) sigsetmask(omask);
1243     }
1244 
1245     return (pid);
1246 }
1247 
1248 static void
1249 okpcntl()
1250 {
1251     if (tpgrp == -1)
1252 	stderror(ERR_JOBCONTROL);
1253     if (tpgrp == 0)
1254 	stderror(ERR_JOBCTRLSUB);
1255 }
1256 
1257 /*
1258  * if we don't have vfork(), things can still go in the wrong order
1259  * resulting in the famous 'Stopped (tty output)'. But some systems
1260  * don't permit the setpgid() call, (these are more recent secure
1261  * systems such as ibm's aix). Then we'd rather print an error message
1262  * than hang the shell!
1263  * I am open to suggestions how to fix that.
1264  */
1265 void
1266 pgetty(wanttty, pgrp)
1267     int     wanttty, pgrp;
1268 {
1269     sigset_t omask = 0;
1270 
1271     /*
1272      * christos: I am blocking the tty signals till I've set things
1273      * correctly....
1274      */
1275     if (wanttty > 0)
1276 	omask = sigblock(sigmask(SIGTSTP)|sigmask(SIGTTIN)|sigmask(SIGTTOU));
1277     /*
1278      * From: Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de>
1279      * Don't check for tpgrp >= 0 so even non-interactive shells give
1280      * background jobs process groups Same for the comparison in the other part
1281      * of the #ifdef
1282      */
1283     if (wanttty >= 0)
1284 	if (setpgid(0, pgrp) == -1) {
1285 	    xprintf("csh: setpgid error.\n");
1286 	    xexit(0);
1287 	}
1288 
1289     if (wanttty > 0) {
1290 	(void) tcsetpgrp(FSHTTY, pgrp);
1291 	(void) sigsetmask(omask);
1292     }
1293 
1294     if (tpgrp > 0)
1295 	tpgrp = 0;		/* gave tty away */
1296 }
1297