xref: /freebsd/contrib/tcsh/sh.proc.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*
2  * sh.proc.c: Job manipulations
3  */
4 /*-
5  * Copyright (c) 1980, 1991 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 #include "sh.h"
33 #include "ed.h"
34 #include "tc.h"
35 #include "tc.wait.h"
36 
37 #ifdef WINNT_NATIVE
38 #undef POSIX
39 #define POSIX
40 #endif /* WINNT_NATIVE */
41 #ifdef aiws
42 # undef HZ
43 # define HZ 16
44 #endif /* aiws */
45 
46 #if defined(_BSD) || (defined(IRIS4D) && __STDC__) || defined(__lucid)
47 # define BSDWAIT
48 #endif /* _BSD || (IRIS4D && __STDC__) || __lucid */
49 #ifndef WTERMSIG
50 # define WTERMSIG(w)	(((union wait *) &(w))->w_termsig)
51 # ifndef BSDWAIT
52 #  define BSDWAIT
53 # endif /* !BSDWAIT */
54 #endif /* !WTERMSIG */
55 #ifndef WEXITSTATUS
56 # define WEXITSTATUS(w)	(((union wait *) &(w))->w_retcode)
57 #endif /* !WEXITSTATUS */
58 #ifndef WSTOPSIG
59 # define WSTOPSIG(w)	(((union wait *) &(w))->w_stopsig)
60 #endif /* !WSTOPSIG */
61 
62 #ifdef __osf__
63 # ifndef WCOREDUMP
64 #  define WCOREDUMP(x) (_W_INT(x) & WCOREFLAG)
65 # endif
66 #endif
67 
68 #ifndef WCOREDUMP
69 # ifdef BSDWAIT
70 #  define WCOREDUMP(w)	(((union wait *) &(w))->w_coredump)
71 # else /* !BSDWAIT */
72 #  define WCOREDUMP(w)	((w) & 0200)
73 # endif /* !BSDWAIT */
74 #endif /* !WCOREDUMP */
75 
76 #ifndef JOBDEBUG
77 # define jobdebug_xprintf(x)	(void)0
78 # define jobdebug_flush()	(void)0
79 #else
80 # define jobdebug_xprintf(s)	xprintf s
81 # define jobdebug_flush()	flush()
82 #endif
83 
84 /*
85  * C Shell - functions that manage processes, handling hanging, termination
86  */
87 
88 #define BIGINDEX	9	/* largest desirable job index */
89 
90 #ifdef BSDTIMES
91 # ifdef convex
92 /* use 'cvxrusage' to get parallel statistics */
93 static struct cvxrusage zru = {{0L, 0L}, {0L, 0L}, 0L, 0L, 0L, 0L,
94 				0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L, 0L,
95 				{0L, 0L}, 0LL, 0LL, 0LL, 0LL, 0L, 0L, 0L,
96 				0LL, 0LL, {0L, 0L, 0L, 0L, 0L}};
97 # else
98 static struct rusage zru;
99 # endif /* convex */
100 #else /* !BSDTIMES */
101 # ifdef _SEQUENT_
102 static struct process_stats zru = {{0L, 0L}, {0L, 0L}, 0, 0, 0, 0, 0, 0, 0,
103 				   0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
104 # else /* !_SEQUENT_ */
105 #  ifdef _SX
106 static struct tms zru = {0, 0, 0, 0}, lru = {0, 0, 0, 0};
107 #  else	/* !_SX */
108 static struct tms zru = {0L, 0L, 0L, 0L}, lru = {0L, 0L, 0L, 0L};
109 #  endif	/* !_SX */
110 # endif	/* !_SEQUENT_ */
111 #endif /* !BSDTIMES */
112 
113 #ifndef BSDTIMES
114 static int timesdone;	/* shtimes buffer full ? */
115 #endif /* BSDTIMES */
116 
117 #ifndef RUSAGE_CHILDREN
118 # define	RUSAGE_CHILDREN	-1
119 #endif /* RUSAGE_CHILDREN */
120 
121 static	void		 pflushall	(void);
122 static	void		 pflush		(struct process *);
123 static	void		 pfree		(struct process *);
124 static	void		 pclrcurr	(struct process *);
125 static	void		 morecommand	(size_t);
126 static	void		 padd		(struct command *);
127 static	int		 pprint		(struct process *, int);
128 static	void		 ptprint	(struct process *);
129 static	void		 pads		(Char *);
130 static	void		 pkill		(Char **, int);
131 static	struct process	*pgetcurr	(struct process *);
132 static	void		 okpcntl	(void);
133 static	void		 setttypgrp	(int);
134 
135 /*
136  * pchild - call queued by the SIGCHLD signal
137  *	indicating that at least one child has terminated or stopped
138  *	thus at least one wait system call will definitely return a
139  *	childs status.  Top level routines (like pwait) must be sure
140  *	to mask interrupts when playing with the proclist data structures!
141  */
142 void
143 pchild(void)
144 {
145     struct process *pp;
146     struct process *fp;
147     pid_t pid;
148 #ifdef BSDWAIT
149     union wait w;
150 #else /* !BSDWAIT */
151     int     w;
152 #endif /* !BSDWAIT */
153     int     jobflags;
154 #ifdef BSDTIMES
155     struct sysrusage ru;
156 #else /* !BSDTIMES */
157 # ifdef _SEQUENT_
158     struct process_stats ru;
159     struct process_stats cpst1, cpst2;
160     timeval_t tv;
161 # else /* !_SEQUENT_ */
162     struct tms proctimes;
163 
164     if (!timesdone) {
165 	timesdone++;
166 	(void) times(&shtimes);
167     }
168 # endif	/* !_SEQUENT_ */
169 #endif /* !BSDTIMES */
170 
171     jobdebug_xprintf(("pchild()\n"));
172 
173 loop:
174     jobdebug_xprintf(("Waiting...\n"));
175     jobdebug_flush();
176     errno = 0;			/* reset, just in case */
177 
178 #ifndef WINNT_NATIVE
179 # ifdef BSDJOBS
180 #  ifdef BSDTIMES
181 #   ifdef convex
182     /* use 'cvxwait' to get parallel statistics */
183     pid = cvxwait(&w,
184         (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), &ru);
185 #   else
186     /* both a wait3 and rusage */
187 #    if !defined(BSDWAIT) || defined(NeXT) || defined(MACH) || defined(__linux__) || defined(__GNU__) || defined(__GLIBC__) || (defined(IRIS4D) && SYSVREL <= 3) || defined(__lucid) || defined(__osf__)
188 #ifdef __ANDROID__ /* no wait3, only wait4 */
189     pid = wait4(-1, &w,
190        (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), &ru);
191 #else
192     pid = wait3(&w,
193        (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), &ru);
194 #endif /* __ANDROID__ */
195 #    else /* BSDWAIT */
196     pid = wait3(&w.w_status,
197        (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), &ru);
198 #    endif /* BSDWAIT */
199 #   endif /* convex */
200 #  else /* !BSDTIMES */
201 #   ifdef _SEQUENT_
202     (void) get_process_stats(&tv, PS_SELF, 0, &cpst1);
203     pid = waitpid(-1, &w,
204 	    (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG));
205     (void) get_process_stats(&tv, PS_SELF, 0, &cpst2);
206     pr_stat_sub(&cpst2, &cpst1, &ru);
207 #   else	/* !_SEQUENT_ */
208 #    ifndef POSIX
209     /* we have a wait3, but no rusage stuff */
210     pid = wait3(&w.w_status,
211 	 (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), 0);
212 #    else /* POSIX */
213     pid = waitpid(-1, &w,
214 	    (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG));
215 #    endif /* POSIX */
216 #   endif /* !_SEQUENT_ */
217 #  endif	/* !BSDTIMES */
218 # else /* !BSDJOBS */
219 #  ifdef BSDTIMES
220 #   define HAVEwait3
221     /* both a wait3 and rusage */
222 #   ifdef hpux
223     pid = wait3(&w.w_status, WNOHANG, 0);
224 #   else	/* !hpux */
225 #     ifndef BSDWAIT
226     pid = wait3(&w, WNOHANG, &ru);
227 #     else
228     pid = wait3(&w.w_status, WNOHANG, &ru);
229 #     endif /* BSDWAIT */
230 #   endif /* !hpux */
231 #  else /* !BSDTIMES */
232 #   ifdef ODT  /* For Sco Unix 3.2.0 or ODT 1.0 */
233 #    define HAVEwait3
234     pid = waitpid(-1, &w,
235  	    (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG));
236 #   endif /* ODT */
237 #   if defined(aiws) || defined(uts)
238 #    define HAVEwait3
239     pid = wait3(&w.w_status,
240 	(setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), 0);
241 #   endif /* aiws || uts */
242 #   ifndef HAVEwait3
243 #    ifndef BSDWAIT
244      /* no wait3, therefore no rusage */
245      /* on Sys V, this may hang.  I hope it's not going to be a problem */
246     pid = wait(&w);
247 #    else /* BSDWAIT */
248      /*
249       * XXX: for greater than 3 we should use waitpid().
250       * but then again, SVR4 falls into the POSIX/BSDJOBS category.
251       */
252     pid = wait(&w.w_status);
253 #    endif /* BSDWAIT */
254 #   endif /* !HAVEwait3 */
255 #  endif	/* !BSDTIMES */
256 # endif /* !BSDJOBS */
257 #else /* WINNT_NATIVE */
258     pid = waitpid(-1, &w,
259 	    (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG));
260 #endif /* WINNT_NATIVE */
261 
262     jobdebug_xprintf(("parent %d pid %d, retval %x termsig %x retcode %x\n",
263 		      (int)getpid(), (int)pid, w, WTERMSIG(w),
264 		      WEXITSTATUS(w)));
265     jobdebug_flush();
266 
267     if ((pid == 0) || (pid == -1)) {
268 	(void)handle_pending_signals();
269 	jobdebug_xprintf(("errno == %d\n", errno));
270 	if (errno == EINTR)
271 	    goto loop;
272 	goto end;
273     }
274     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next)
275 	if (pid == pp->p_procid)
276 	    goto found;
277 #if !defined(BSDJOBS) && !defined(WINNT_NATIVE)
278     /* this should never have happened */
279     stderror(ERR_SYNC, pid);
280     xexit(0);
281 #else /* BSDJOBS || WINNT_NATIVE */
282     goto loop;
283 #endif /* !BSDJOBS && !WINNT_NATIVE */
284 found:
285     pp->p_flags &= ~(PRUNNING | PSTOPPED | PREPORTED);
286     if (WIFSTOPPED(w)) {
287 	pp->p_flags |= PSTOPPED;
288 	pp->p_reason = WSTOPSIG(w);
289     }
290     else {
291 	if (pp->p_flags & (PTIME | PPTIME) || adrof(STRtime))
292 #ifndef BSDTIMES
293 # ifdef _SEQUENT_
294 	    (void) get_process_stats(&pp->p_etime, PS_SELF, NULL, NULL);
295 # else	/* !_SEQUENT_ */
296 	    pp->p_etime = times(&proctimes);
297 # endif	/* !_SEQUENT_ */
298 #else /* BSDTIMES */
299 	    (void) gettimeofday(&pp->p_etime, NULL);
300 #endif /* BSDTIMES */
301 
302 
303 #if defined(BSDTIMES) || defined(_SEQUENT_)
304 	pp->p_rusage = ru;
305 #else /* !BSDTIMES && !_SEQUENT_ */
306 	(void) times(&proctimes);
307 	pp->p_utime = proctimes.tms_cutime - shtimes.tms_cutime;
308 	pp->p_stime = proctimes.tms_cstime - shtimes.tms_cstime;
309 	shtimes = proctimes;
310 #endif /* !BSDTIMES && !_SEQUENT_ */
311 	if (WIFSIGNALED(w)) {
312 	    if (WTERMSIG(w) == SIGINT)
313 		pp->p_flags |= PINTERRUPTED;
314 	    else
315 		pp->p_flags |= PSIGNALED;
316 	    if (WCOREDUMP(w))
317 		pp->p_flags |= PDUMPED;
318 	    pp->p_reason = WTERMSIG(w);
319 	}
320 	else {
321 	    pp->p_reason = WEXITSTATUS(w);
322 	    if (pp->p_reason != 0)
323 		pp->p_flags |= PAEXITED;
324 	    else
325 		pp->p_flags |= PNEXITED;
326 	}
327     }
328     jobflags = 0;
329     fp = pp;
330     do {
331 	if ((fp->p_flags & (PPTIME | PRUNNING | PSTOPPED)) == 0 &&
332 	    !child && adrof(STRtime) &&
333 #ifdef BSDTIMES
334 	    fp->p_rusage.ru_utime.tv_sec + fp->p_rusage.ru_stime.tv_sec
335 #else /* !BSDTIMES */
336 # ifdef _SEQUENT_
337 	    fp->p_rusage.ps_utime.tv_sec + fp->p_rusage.ps_stime.tv_sec
338 # else /* !_SEQUENT_ */
339 #  ifndef POSIX
340 	    (fp->p_utime + fp->p_stime) / HZ
341 #  else /* POSIX */
342 	    (fp->p_utime + fp->p_stime) / clk_tck
343 #  endif /* POSIX */
344 # endif /* !_SEQUENT_ */
345 #endif /* !BSDTIMES */
346 	    >= atoi(short2str(varval(STRtime))))
347 	    fp->p_flags |= PTIME;
348 	jobflags |= fp->p_flags;
349     } while ((fp = fp->p_friends) != pp);
350     pp->p_flags &= ~PFOREGND;
351     if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
352 	pp->p_flags &= ~PPTIME;
353 	pp->p_flags |= PTIME;
354     }
355     if ((jobflags & (PRUNNING | PREPORTED)) == 0) {
356 	fp = pp;
357 	do {
358 	    if (fp->p_flags & PSTOPPED)
359 		fp->p_flags |= PREPORTED;
360 	} while ((fp = fp->p_friends) != pp);
361 	while (fp->p_procid != fp->p_jobid)
362 	    fp = fp->p_friends;
363 	if (jobflags & PSTOPPED) {
364 	    if (pcurrent && pcurrent != fp)
365 		pprevious = pcurrent;
366 	    pcurrent = fp;
367 	}
368 	else
369 	    pclrcurr(fp);
370 	if (jobflags & PFOREGND) {
371 	    if (!(jobflags & (PSIGNALED | PSTOPPED | PPTIME) ||
372 #ifdef notdef
373 		jobflags & PAEXITED ||
374 #endif /* notdef */
375 		fp->p_cwd == NULL ||
376 		!eq(dcwd->di_name, fp->p_cwd->di_name))) {
377 	    /* PWP: print a newline after ^C */
378 		if (jobflags & PINTERRUPTED) {
379 		    xputchar('\r' | QUOTE);
380 		    xputchar('\n');
381 		}
382 #ifdef notdef
383 		else if ((jobflags & (PTIME|PSTOPPED)) == PTIME)
384 		    ptprint(fp);
385 #endif /* notdef */
386 	    }
387 	}
388 	else {
389 	    if (jobflags & PNOTIFY || adrof(STRnotify)) {
390 	        xputchar('\r' | QUOTE);
391 		xputchar('\n');
392 		(void) pprint(pp, NUMBER | NAME | REASON);
393 		if ((jobflags & PSTOPPED) == 0)
394 		    pflush(pp);
395 		if (GettingInput) {
396 		    errno = 0;
397 		    (void) Rawmode();
398 #ifdef notdef
399 		    /*
400 		     * don't really want to do that, because it
401 		     * will erase our message in case of multi-line
402 		     * input
403 		     */
404 		    ClearLines();
405 #endif /* notdef */
406 		    ClearDisp();
407 		    Refresh();
408 		}
409 	    }
410 	    else {
411 		fp->p_flags |= PNEEDNOTE;
412 		neednote = 1;
413 	    }
414 	}
415     }
416 #if defined(BSDJOBS) || defined(HAVEwait3) ||defined(WINNT_NATIVE)
417     goto loop;
418 #endif /* BSDJOBS || HAVEwait3 */
419  end:
420     ;
421 }
422 
423 void
424 pnote(void)
425 {
426     struct process *pp;
427     int     flags;
428 
429     neednote = 0;
430     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next) {
431 	if (pp->p_flags & PNEEDNOTE) {
432 	    pchild_disabled++;
433 	    cleanup_push(&pchild_disabled, disabled_cleanup);
434 	    pp->p_flags &= ~PNEEDNOTE;
435 	    flags = pprint(pp, NUMBER | NAME | REASON);
436 	    if ((flags & (PRUNNING | PSTOPPED)) == 0)
437 		pflush(pp);
438 	    cleanup_until(&pchild_disabled);
439 	}
440     }
441 }
442 
443 
444 static void
445 pfree(struct process *pp)
446 {
447     xfree(pp->p_command);
448     if (pp->p_cwd && --pp->p_cwd->di_count == 0)
449 	if (pp->p_cwd->di_next == 0)
450 	    dfree(pp->p_cwd);
451     xfree(pp);
452 }
453 
454 
455 /*
456  * pwait - wait for current job to terminate, maintaining integrity
457  *	of current and previous job indicators.
458  */
459 void
460 pwait(void)
461 {
462     struct process *fp, *pp;
463 
464     /*
465      * Here's where dead procs get flushed.
466      */
467     for (pp = (fp = &proclist)->p_next; pp != NULL; pp = (fp = pp)->p_next)
468 	if (pp->p_procid == 0) {
469 	    fp->p_next = pp->p_next;
470 	    pfree(pp);
471 	    pp = fp;
472 	}
473     pjwait(pcurrjob);
474 }
475 
476 
477 /*
478  * pjwait - wait for a job to finish or become stopped
479  *	It is assumed to be in the foreground state (PFOREGND)
480  */
481 void
482 pjwait(struct process *pp)
483 {
484     struct process *fp;
485     int     jobflags, reason;
486     sigset_t oset, set, pause_mask;
487     Char *reason_str;
488 
489     while (pp->p_procid != pp->p_jobid)
490 	pp = pp->p_friends;
491     fp = pp;
492 
493     do {
494 	if ((fp->p_flags & (PFOREGND | PRUNNING)) == PRUNNING)
495 	  xprintf("%s", CGETS(17, 1, "BUG: waiting for background job!\n"));
496     } while ((fp = fp->p_friends) != pp);
497     /*
498      * Now keep pausing as long as we are not interrupted (SIGINT), and the
499      * target process, or any of its friends, are running
500      */
501     fp = pp;
502     sigemptyset(&set);
503     sigaddset(&set, SIGINT);
504     sigaddset(&set, SIGCHLD);
505     (void)sigprocmask(SIG_BLOCK, &set, &oset);
506     cleanup_push(&oset, sigprocmask_cleanup);
507     pause_mask = oset;
508     sigdelset(&pause_mask, SIGCHLD);
509     sigaddset(&pause_mask, SIGINT);
510     for (;;) {
511 	(void)handle_pending_signals();
512 	jobflags = 0;
513 	do
514 	    jobflags |= fp->p_flags;
515 	while ((fp = (fp->p_friends)) != pp);
516 	if ((jobflags & PRUNNING) == 0)
517 	    break;
518 	jobdebug_xprintf(("%d starting to sigsuspend for SIGCHLD on %d\n",
519 			  getpid(), fp->p_procid));
520 	sigsuspend(&pause_mask);
521     }
522     cleanup_until(&oset);
523     jobdebug_xprintf(("%d returned from sigsuspend loop\n", getpid()));
524 #ifdef BSDJOBS
525     if (tpgrp > 0)		/* get tty back */
526 	(void) tcsetpgrp(FSHTTY, tpgrp);
527 #endif /* BSDJOBS */
528     if ((jobflags & (PSIGNALED | PSTOPPED | PTIME)) ||
529 	fp->p_cwd == NULL || !eq(dcwd->di_name, fp->p_cwd->di_name)) {
530 	if (jobflags & PSTOPPED) {
531 	    xputchar('\n');
532 	    if (adrof(STRlistjobs)) {
533 		Char   *jobcommand[3];
534 
535 		jobcommand[0] = STRjobs;
536 		if (eq(varval(STRlistjobs), STRlong))
537 		    jobcommand[1] = STRml;
538 		else
539 		    jobcommand[1] = NULL;
540 		jobcommand[2] = NULL;
541 
542 		dojobs(jobcommand, NULL);
543 		(void) pprint(pp, SHELLDIR);
544 	    }
545 	    else
546 		(void) pprint(pp, AREASON | SHELLDIR);
547 	}
548 	else
549 	    (void) pprint(pp, AREASON | SHELLDIR);
550     }
551     if ((jobflags & (PINTERRUPTED | PSTOPPED)) && setintr &&
552 	(!gointr || !eq(gointr, STRminus))) {
553 	if ((jobflags & PSTOPPED) == 0)
554 	    pflush(pp);
555 	pintr1(0);
556 	/* NOTREACHED */
557     }
558     reason = 0;
559     fp = pp;
560     do {
561 	/* In case of pipelines only the result of the last
562 	 * command should be taken in account */
563 	if (!anyerror && !(fp->p_flags & PBRACE)
564 		&& ((fp->p_flags & PPOU) || (fp->p_flags & PBACKQ)))
565 	    continue;
566 	if (fp->p_reason)
567 	    reason = fp->p_flags & (PSIGNALED | PINTERRUPTED) ?
568 		fp->p_reason | META : fp->p_reason;
569     } while ((fp = fp->p_friends) != pp);
570     /*
571      * Don't report on backquoted jobs, cause it will mess up
572      * their output.
573      */
574     if ((reason != 0) && (adrof(STRprintexitvalue)) &&
575 	(pp->p_flags & PBACKQ) == 0)
576 	xprintf(CGETS(17, 2, "Exit %d\n"), reason);
577     reason_str = putn((tcsh_number_t)reason);
578     cleanup_push(reason_str, xfree);
579     setv(STRstatus, reason_str, VAR_READWRITE);
580     cleanup_ignore(reason_str);
581     cleanup_until(reason_str);
582     if (reason && exiterr)
583 	exitstat();
584     pflush(pp);
585 }
586 
587 /*
588  * dowait - wait for all processes to finish
589  */
590 
591 /*ARGSUSED*/
592 void
593 dowait(Char **v, struct command *c)
594 {
595     struct process *pp;
596 
597     /* the current block mask to be able to restore */
598     sigset_t old_mask;
599 
600     /* block mask for critical section: OLD_MASK U {SIGCHLD} */
601     sigset_t block_mask;
602 
603     /* ignore those during blocking sigsuspend:
604        OLD_MASK / {SIGCHLD, possibly(SIGINT)} */
605     sigset_t pause_mask;
606 
607     int opintr_disabled, gotsig;
608 
609     USE(c);
610     USE(v);
611     pjobs++;
612 
613     sigprocmask(SIG_BLOCK, NULL, &pause_mask);
614     sigdelset(&pause_mask, SIGCHLD);
615     if (setintr)
616 	sigdelset(&pause_mask, SIGINT);
617 
618     /* critical section, block also SIGCHLD */
619     sigprocmask(SIG_BLOCK, NULL, &block_mask);
620     sigaddset(&block_mask, SIGCHLD);
621     sigprocmask(SIG_BLOCK, &block_mask, &old_mask);
622 
623     /* detect older SIGCHLDs and remove PRUNNING flag from proclist */
624     (void)handle_pending_signals();
625 
626 loop:
627     for (pp = proclist.p_next; pp; pp = pp->p_next)
628 	if (pp->p_procid &&	/* pp->p_procid == pp->p_jobid && */
629 	    pp->p_flags & PRUNNING) {
630 	    /* wait for (or pick up alredy blocked) SIGCHLD */
631 	    sigsuspend(&pause_mask);
632 
633 	    /* make the 'wait' interuptable by CTRL-C */
634 	    opintr_disabled = pintr_disabled;
635 	    pintr_disabled = 0;
636 	    gotsig = handle_pending_signals();
637 	    pintr_disabled = opintr_disabled;
638 	    if (gotsig)
639 		break;
640 	    goto loop;
641 	}
642     pjobs = 0;
643 
644     sigprocmask(SIG_SETMASK, &old_mask, NULL);
645 }
646 
647 /*
648  * pflushall - flush all jobs from list (e.g. at fork())
649  */
650 static void
651 pflushall(void)
652 {
653     struct process *pp;
654 
655     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next)
656 	if (pp->p_procid)
657 	    pflush(pp);
658 }
659 
660 /*
661  * pflush - flag all process structures in the same job as the
662  *	the argument process for deletion.  The actual free of the
663  *	space is not done here since pflush is called at interrupt level.
664  */
665 static void
666 pflush(struct process *pp)
667 {
668     struct process *np;
669     int idx;
670 
671     if (pp->p_procid == 0) {
672 	xprintf("%s", CGETS(17, 3, "BUG: process flushed twice"));
673 	return;
674     }
675     while (pp->p_procid != pp->p_jobid)
676 	pp = pp->p_friends;
677     pclrcurr(pp);
678     if (pp == pcurrjob)
679 	pcurrjob = 0;
680     idx = pp->p_index;
681     np = pp;
682     do {
683 	np->p_index = np->p_procid = 0;
684 	np->p_flags &= ~PNEEDNOTE;
685     } while ((np = np->p_friends) != pp);
686     if (idx == pmaxindex) {
687 	for (np = proclist.p_next, idx = 0; np; np = np->p_next)
688 	    if (np->p_index > idx)
689 		idx = np->p_index;
690 	pmaxindex = idx;
691     }
692 }
693 
694 /*
695  * pclrcurr - make sure the given job is not the current or previous job;
696  *	pp MUST be the job leader
697  */
698 static void
699 pclrcurr(struct process *pp)
700 {
701     if (pp == pcurrent) {
702 	if (pprevious != NULL) {
703 	    pcurrent = pprevious;
704 	    pprevious = pgetcurr(pp);
705 	}
706 	else {
707 	    pcurrent = pgetcurr(pp);
708 	    pprevious = pgetcurr(pp);
709 	}
710     }
711     else if (pp == pprevious)
712 	pprevious = pgetcurr(pp);
713 }
714 
715 /* +4 here is 1 for '\0', 1 ea for << >& >> */
716 static Char *cmdstr;
717 static size_t cmdmax;
718 static size_t cmdlen;
719 static Char *cmdp;
720 #define CMD_INIT 1024
721 #define CMD_INCR 64
722 
723 static void
724 morecommand(size_t s)
725 {
726     Char *ncmdstr;
727     ptrdiff_t d;
728 
729     cmdmax += s;
730     ncmdstr = xrealloc(cmdstr, cmdmax * sizeof(*cmdstr));
731     d = ncmdstr - cmdstr;
732     cmdstr = ncmdstr;
733     cmdp += d;
734 }
735 
736 /* GrP
737  * unparse - Export padd() functionality
738  */
739 Char *
740 unparse(struct command *t)
741 {
742     if (cmdmax == 0)
743 	morecommand(CMD_INIT);
744     cmdp = cmdstr;
745     cmdlen = 0;
746     padd(t);
747     *cmdp++ = '\0';
748     return Strsave(cmdstr);
749 }
750 
751 
752 /*
753  * palloc - allocate a process structure and fill it up.
754  *	an important assumption is made that the process is running.
755  */
756 void
757 palloc(pid_t pid, struct command *t)
758 {
759     struct process *pp;
760     int     i;
761 
762     pp = xcalloc(1, sizeof(struct process));
763     pp->p_procid = pid;
764     pp->p_parentid = shpgrp;
765     pp->p_flags = ((t->t_dflg & F_AMPERSAND) ? 0 : PFOREGND) | PRUNNING;
766     if (t->t_dflg & F_TIME)
767 	pp->p_flags |= PPTIME;
768     if (t->t_dflg & F_BACKQ)
769 	pp->p_flags |= PBACKQ;
770     if (t->t_dflg & F_HUP)
771 	pp->p_flags |= PHUP;
772     if (t->t_dcom && t->t_dcom[0] && (*t->t_dcom[0] == '{'))
773 	pp->p_flags |= PBRACE;
774     if (cmdmax == 0)
775 	morecommand(CMD_INIT);
776     cmdp = cmdstr;
777     cmdlen = 0;
778     padd(t);
779     *cmdp++ = 0;
780     if (t->t_dflg & F_PIPEOUT) {
781 	pp->p_flags |= PPOU;
782 	if (t->t_dflg & F_STDERR)
783 	    pp->p_flags |= PDIAG;
784     }
785     pp->p_command = Strsave(cmdstr);
786     if (pcurrjob) {
787 	struct process *fp;
788 
789 	/* careful here with interrupt level */
790 	pp->p_cwd = 0;
791 	pp->p_index = pcurrjob->p_index;
792 	pp->p_friends = pcurrjob;
793 	pp->p_jobid = pcurrjob->p_procid;
794 	for (fp = pcurrjob; fp->p_friends != pcurrjob; fp = fp->p_friends)
795 	    continue;
796 	fp->p_friends = pp;
797     }
798     else {
799 	pcurrjob = pp;
800 	pp->p_jobid = pid;
801 	pp->p_friends = pp;
802 	pp->p_cwd = dcwd;
803 	dcwd->di_count++;
804 	if (pmaxindex < BIGINDEX)
805 	    pp->p_index = ++pmaxindex;
806 	else {
807 	    struct process *np;
808 
809 	    for (i = 1;; i++) {
810 		for (np = proclist.p_next; np; np = np->p_next)
811 		    if (np->p_index == i)
812 			goto tryagain;
813 		pp->p_index = i;
814 		if (i > pmaxindex)
815 		    pmaxindex = i;
816 		break;
817 	tryagain:;
818 	    }
819 	}
820 	if (pcurrent == NULL)
821 	    pcurrent = pp;
822 	else if (pprevious == NULL)
823 	    pprevious = pp;
824     }
825     pp->p_next = proclist.p_next;
826     proclist.p_next = pp;
827 #ifdef BSDTIMES
828     (void) gettimeofday(&pp->p_btime, NULL);
829 #else /* !BSDTIMES */
830 # ifdef _SEQUENT_
831     (void) get_process_stats(&pp->p_btime, PS_SELF, NULL, NULL);
832 # else /* !_SEQUENT_ */
833     {
834 	struct tms tmptimes;
835 
836 	pp->p_btime = times(&tmptimes);
837     }
838 # endif /* !_SEQUENT_ */
839 #endif /* !BSDTIMES */
840 }
841 
842 static void
843 padd(struct command *t)
844 {
845     Char  **argp;
846 
847     if (t == 0)
848 	return;
849     switch (t->t_dtyp) {
850 
851     case NODE_PAREN:
852 	pads(STRLparensp);
853 	padd(t->t_dspr);
854 	pads(STRspRparen);
855 	break;
856 
857     case NODE_COMMAND:
858 	for (argp = t->t_dcom; *argp; argp++) {
859 	    pads(*argp);
860 	    if (argp[1])
861 		pads(STRspace);
862 	}
863 	break;
864 
865     case NODE_OR:
866     case NODE_AND:
867     case NODE_PIPE:
868     case NODE_LIST:
869 	padd(t->t_dcar);
870 	switch (t->t_dtyp) {
871 	case NODE_OR:
872 	    pads(STRspor2sp);
873 	    break;
874 	case NODE_AND:
875 	    pads(STRspand2sp);
876 	    break;
877 	case NODE_PIPE:
878 	    pads(STRsporsp);
879 	    break;
880 	case NODE_LIST:
881 	    pads(STRsemisp);
882 	    break;
883 	default:
884 	    break;
885 	}
886 	padd(t->t_dcdr);
887 	return;
888 
889     default:
890 	break;
891     }
892     if ((t->t_dflg & F_PIPEIN) == 0 && t->t_dlef) {
893 	pads((t->t_dflg & F_READ) ? STRspLarrow2sp : STRspLarrowsp);
894 	pads(t->t_dlef);
895     }
896     if ((t->t_dflg & F_PIPEOUT) == 0 && t->t_drit) {
897 	pads((t->t_dflg & F_APPEND) ? STRspRarrow2 : STRspRarrow);
898 	if (t->t_dflg & F_STDERR)
899 	    pads(STRand);
900 	pads(STRspace);
901 	pads(t->t_drit);
902     }
903 }
904 
905 static void
906 pads(Char *cp)
907 {
908     size_t i, len;
909 
910     /*
911      * Avoid the Quoted Space alias hack! Reported by:
912      * sam@john-bigboote.ICS.UCI.EDU (Sam Horrocks)
913      */
914     if (cp[0] == STRQNULL[0])
915 	cp++;
916 
917     i = Strlen(cp);
918 
919     len = cmdlen + i + CMD_INCR;
920     if (len >= cmdmax)
921 	morecommand(len);
922     (void) Strcpy(cmdp, cp);
923     cmdp += i;
924     cmdlen += i;
925 }
926 
927 /*
928  * psavejob - temporarily save the current job on a one level stack
929  *	so another job can be created.  Used for { } in exp6
930  *	and `` in globbing.
931  */
932 void
933 psavejob(void)
934 {
935     pholdjob = pcurrjob;
936     pcurrjob = NULL;
937 }
938 
939 void
940 psavejob_cleanup(void *dummy)
941 {
942     USE(dummy);
943     pcurrjob = pholdjob;
944     pholdjob = NULL;
945 }
946 
947 /*
948  * pendjob - indicate that a job (set of commands) has been completed
949  *	or is about to begin.
950  */
951 void
952 pendjob(void)
953 {
954     struct process *pp, *tp;
955 
956     if (pcurrjob && (pcurrjob->p_flags & (PFOREGND | PSTOPPED)) == 0) {
957 	pp = pcurrjob;
958 	pcurrjob = NULL;
959 	while (pp->p_procid != pp->p_jobid)
960 	    pp = pp->p_friends;
961 	xprintf("[%d]", pp->p_index);
962 	tp = pp;
963 	do {
964 	    xprintf(" %d", pp->p_procid);
965 	    pp = pp->p_friends;
966 	} while (pp != tp);
967 	xputchar('\n');
968     }
969     pholdjob = pcurrjob = 0;
970 }
971 
972 /*
973  * pprint - print a job
974  */
975 
976 /*
977  * Hacks have been added for SVR4 to deal with pipe's being spawned in
978  * reverse order
979  *
980  * David Dawes (dawes@physics.su.oz.au) Oct 1991
981  */
982 
983 static int
984 pprint(struct process *pp, int flag)
985 {
986     int status, reason;
987     struct process *tp;
988     int     jobflags, pstatus, pcond;
989     const char *format;
990     int ohaderr;
991 
992 #ifdef BACKPIPE
993     struct process *pipehead = NULL, *pipetail = NULL, *pmarker = NULL;
994     int inpipe = 0;
995 #endif /* BACKPIPE */
996 
997     while (pp->p_procid != pp->p_jobid)
998 	pp = pp->p_friends;
999     if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
1000 	pp->p_flags &= ~PPTIME;
1001 	pp->p_flags |= PTIME;
1002     }
1003     tp = pp;
1004     status = reason = -1;
1005     jobflags = 0;
1006     ohaderr = haderr;
1007     /* Print status to stderr, except for jobs built-in */
1008     haderr = !(flag & JOBLIST);
1009     do {
1010 #ifdef BACKPIPE
1011 	/*
1012 	 * The pipeline is reversed, so locate the real head of the pipeline
1013 	 * if pp is at the tail of a pipe (and not already in a pipeline)
1014 	 */
1015 	if ((pp->p_friends->p_flags & PPOU) && !inpipe && (flag & NAME)) {
1016 	    inpipe = 1;
1017 	    pipetail = pp;
1018 	    do
1019 		pp = pp->p_friends;
1020 	    while (pp->p_friends->p_flags & PPOU);
1021 	    pipehead = pp;
1022 	    pmarker = pp;
1023 	/*
1024 	 * pmarker is used to hold the place of the proc being processed, so
1025 	 * we can search for the next one downstream later.
1026 	 */
1027 	}
1028 	pcond = (tp != pp || (inpipe && tp == pp));
1029 #else /* !BACKPIPE */
1030 	pcond = (tp != pp);
1031 #endif /* BACKPIPE */
1032 
1033 	jobflags |= pp->p_flags;
1034 	pstatus = (int) (pp->p_flags & PALLSTATES);
1035 	if (pcond && linp != linbuf && !(flag & FANCY) &&
1036 	    ((pstatus == status && pp->p_reason == reason) ||
1037 	     !(flag & REASON)))
1038 	    xputchar(' ');
1039 	else {
1040 	    if (pcond && linp != linbuf)
1041 		xputchar('\n');
1042 	    if (flag & NUMBER) {
1043 #ifdef BACKPIPE
1044 		pcond = ((pp == tp && !inpipe) ||
1045 			 (inpipe && pipetail == tp && pp == pipehead));
1046 #else /* BACKPIPE */
1047 		pcond = (pp == tp);
1048 #endif /* BACKPIPE */
1049 		if (pcond)
1050 		    xprintf("[%d]%s %c ", pp->p_index,
1051 			    pp->p_index < 10 ? " " : "",
1052 			    pp == pcurrent ? '+' :
1053 			    (pp == pprevious ? '-' : ' '));
1054 		else
1055 		    xprintf("       ");
1056 	    }
1057 	    if (flag & FANCY) {
1058 		xprintf("%5d ", pp->p_procid);
1059 #ifdef TCF
1060 		xprintf("%11s ", sitename(pp->p_procid));
1061 #endif /* TCF */
1062 	    }
1063 	    if (flag & (REASON | AREASON)) {
1064 		if (flag & NAME)
1065 		    format = "%-30s";
1066 		else
1067 		    format = "%s";
1068 		if (pstatus == status) {
1069 		    if (pp->p_reason == reason) {
1070 			xprintf(format, "");
1071 			goto prcomd;
1072 		    }
1073 		    else
1074 			reason = (int) pp->p_reason;
1075 		}
1076 		else {
1077 		    status = pstatus;
1078 		    reason = (int) pp->p_reason;
1079 		}
1080 		switch (status) {
1081 
1082 		case PRUNNING:
1083 		    xprintf(format, CGETS(17, 4, "Running "));
1084 		    break;
1085 
1086 		case PINTERRUPTED:
1087 		case PSTOPPED:
1088 		case PSIGNALED:
1089 		    /*
1090 		     * tell what happened to the background job
1091 		     * From: Michael Schroeder
1092 		     * <mlschroe@immd4.informatik.uni-erlangen.de>
1093 		     */
1094 		    if ((flag & REASON)
1095 			|| ((flag & AREASON)
1096 			    && reason != SIGINT
1097 			    && (reason != SIGPIPE
1098 				|| (pp->p_flags & PPOU) == 0))) {
1099 			char *ptr;
1100 			int free_ptr;
1101 
1102 			free_ptr = 0;
1103 			ptr = (char *)(intptr_t)mesg[pp->p_reason & 0177].pname;
1104 			if (ptr == NULL) {
1105 			    ptr = xasprintf("%s %d", CGETS(17, 5, "Signal"),
1106 					    pp->p_reason & 0177);
1107 			    cleanup_push(ptr, xfree);
1108 			    free_ptr = 1;
1109 			}
1110 			xprintf(format, ptr);
1111 			if (free_ptr != 0)
1112 			    cleanup_until(ptr);
1113 		    }
1114 		    else
1115 			reason = -1;
1116 		    break;
1117 
1118 		case PNEXITED:
1119 		case PAEXITED:
1120 		    if (flag & REASON) {
1121 			if (pp->p_reason)
1122 			    xprintf(CGETS(17, 6, "Exit %-25d"), pp->p_reason);
1123 			else
1124 			    xprintf(format, CGETS(17, 7, "Done"));
1125 		    }
1126 		    break;
1127 
1128 		default:
1129 		    xprintf(CGETS(17, 8, "BUG: status=%-9o"),
1130 			    status);
1131 		}
1132 	    }
1133 	}
1134 prcomd:
1135 	if (flag & NAME) {
1136 	    xprintf("%S", pp->p_command);
1137 	    if (pp->p_flags & PPOU)
1138 		xprintf(" |");
1139 	    if (pp->p_flags & PDIAG)
1140 		xprintf("&");
1141 	}
1142 	if (flag & (REASON | AREASON) && pp->p_flags & PDUMPED)
1143 	    xprintf("%s", CGETS(17, 9, " (core dumped)"));
1144 	if (tp == pp->p_friends) {
1145 	    if (flag & AMPERSAND)
1146 		xprintf(" &");
1147 	    if (flag & JOBDIR &&
1148 		!eq(tp->p_cwd->di_name, dcwd->di_name)) {
1149 		xprintf("%s", CGETS(17, 10, " (wd: "));
1150 		dtildepr(tp->p_cwd->di_name);
1151 		xprintf(")");
1152 	    }
1153 	}
1154 	if (pp->p_flags & PPTIME && !(status & (PSTOPPED | PRUNNING))) {
1155 	    if (linp != linbuf)
1156 		xprintf("\n\t");
1157 #if defined(BSDTIMES) || defined(_SEQUENT_)
1158 	    prusage(&zru, &pp->p_rusage, &pp->p_etime,
1159 		    &pp->p_btime);
1160 #else /* !BSDTIMES && !SEQUENT */
1161 	    lru.tms_utime = pp->p_utime;
1162 	    lru.tms_stime = pp->p_stime;
1163 	    lru.tms_cutime = 0;
1164 	    lru.tms_cstime = 0;
1165 	    prusage(&zru, &lru, pp->p_etime,
1166 		    pp->p_btime);
1167 #endif /* !BSDTIMES && !SEQUENT */
1168 
1169 	}
1170 #ifdef BACKPIPE
1171 	pcond = ((tp == pp->p_friends && !inpipe) ||
1172 		 (inpipe && pipehead->p_friends == tp && pp == pipetail));
1173 #else  /* !BACKPIPE */
1174 	pcond = (tp == pp->p_friends);
1175 #endif /* BACKPIPE */
1176 	if (pcond) {
1177 	    if (linp != linbuf)
1178 		xputchar('\n');
1179 	    if (flag & SHELLDIR && !eq(tp->p_cwd->di_name, dcwd->di_name)) {
1180 		xprintf("%s", CGETS(17, 11, "(wd now: "));
1181 		dtildepr(dcwd->di_name);
1182 		xprintf(")\n");
1183 	    }
1184 	}
1185 #ifdef BACKPIPE
1186 	if (inpipe) {
1187 	    /*
1188 	     * if pmaker == pipetail, we are finished that pipeline, and
1189 	     * can now skip to past the head
1190 	     */
1191 	    if (pmarker == pipetail) {
1192 		inpipe = 0;
1193 		pp = pipehead;
1194 	    }
1195 	    else {
1196 	    /*
1197 	     * set pp to one before the one we want next, so the while below
1198 	     * increments to the correct spot.
1199 	     */
1200 		do
1201 		    pp = pp->p_friends;
1202 	    	while (pp->p_friends->p_friends != pmarker);
1203 	    	pmarker = pp->p_friends;
1204 	    }
1205 	}
1206 	pcond = ((pp = pp->p_friends) != tp || inpipe);
1207 #else /* !BACKPIPE */
1208 	pcond = ((pp = pp->p_friends) != tp);
1209 #endif /* BACKPIPE */
1210     } while (pcond);
1211 
1212     if (jobflags & PTIME && (jobflags & (PSTOPPED | PRUNNING)) == 0) {
1213 	if (jobflags & NUMBER)
1214 	    xprintf("       ");
1215 	ptprint(tp);
1216     }
1217     haderr = ohaderr;
1218     return (jobflags);
1219 }
1220 
1221 /*
1222  * All 4.3 BSD derived implementations are buggy and I've had enough.
1223  * The following implementation produces similar code and works in all
1224  * cases. The 4.3BSD one works only for <, >, !=
1225  */
1226 # undef timercmp
1227 #  define timercmp(tvp, uvp, cmp) \
1228       (((tvp)->tv_sec == (uvp)->tv_sec) ? \
1229 	   ((tvp)->tv_usec cmp (uvp)->tv_usec) : \
1230 	   ((tvp)->tv_sec  cmp (uvp)->tv_sec))
1231 
1232 static void
1233 ptprint(struct process *tp)
1234 {
1235 #ifdef BSDTIMES
1236     struct timeval tetime, diff;
1237     static struct timeval ztime;
1238     struct sysrusage ru;
1239     struct process *pp = tp;
1240 
1241     ru = zru;
1242     tetime = ztime;
1243     do {
1244 	ruadd(&ru, &pp->p_rusage);
1245 	tvsub(&diff, &pp->p_etime, &pp->p_btime);
1246 	if (timercmp(&diff, &tetime, >))
1247 	    tetime = diff;
1248     } while ((pp = pp->p_friends) != tp);
1249     prusage(&zru, &ru, &tetime, &ztime);
1250 #else /* !BSDTIMES */
1251 # ifdef _SEQUENT_
1252     timeval_t tetime, diff;
1253     static timeval_t ztime;
1254     struct process_stats ru;
1255     struct process *pp = tp;
1256 
1257     ru = zru;
1258     tetime = ztime;
1259     do {
1260 	ruadd(&ru, &pp->p_rusage);
1261 	tvsub(&diff, &pp->p_etime, &pp->p_btime);
1262 	if (timercmp(&diff, &tetime, >))
1263 	    tetime = diff;
1264     } while ((pp = pp->p_friends) != tp);
1265     prusage(&zru, &ru, &tetime, &ztime);
1266 # else /* !_SEQUENT_ */
1267 #  ifndef POSIX
1268     static time_t ztime = 0;
1269     static time_t zu_time = 0;
1270     static time_t zs_time = 0;
1271     time_t  tetime, diff;
1272     time_t  u_time, s_time;
1273 
1274 #  else	/* POSIX */
1275     static clock_t ztime = 0;
1276     static clock_t zu_time = 0;
1277     static clock_t zs_time = 0;
1278     clock_t tetime, diff;
1279     clock_t u_time, s_time;
1280 
1281 #  endif /* POSIX */
1282     struct tms zts, rts;
1283     struct process *pp = tp;
1284 
1285     u_time = zu_time;
1286     s_time = zs_time;
1287     tetime = ztime;
1288     do {
1289 	u_time += pp->p_utime;
1290 	s_time += pp->p_stime;
1291 	diff = pp->p_etime - pp->p_btime;
1292 	if (diff > tetime)
1293 	    tetime = diff;
1294     } while ((pp = pp->p_friends) != tp);
1295     zts.tms_utime = zu_time;
1296     zts.tms_stime = zs_time;
1297     zts.tms_cutime = 0;
1298     zts.tms_cstime = 0;
1299     rts.tms_utime = u_time;
1300     rts.tms_stime = s_time;
1301     rts.tms_cutime = 0;
1302     rts.tms_cstime = 0;
1303     prusage(&zts, &rts, tetime, ztime);
1304 # endif /* !_SEQUENT_ */
1305 #endif	/* !BSDTIMES */
1306 }
1307 
1308 /*
1309  * dojobs - print all jobs
1310  */
1311 /*ARGSUSED*/
1312 void
1313 dojobs(Char **v, struct command *c)
1314 {
1315     struct process *pp;
1316     int flag = NUMBER | NAME | REASON | JOBLIST;
1317     int     i;
1318 
1319     USE(c);
1320     if (chkstop)
1321 	chkstop = 2;
1322     if (*++v) {
1323 	if (v[1] || !eq(*v, STRml))
1324 	    stderror(ERR_JOBS);
1325 	flag |= FANCY | JOBDIR;
1326     }
1327     for (i = 1; i <= pmaxindex; i++)
1328 	for (pp = proclist.p_next; pp; pp = pp->p_next)
1329 	    if (pp->p_index == i && pp->p_procid == pp->p_jobid) {
1330 		pp->p_flags &= ~PNEEDNOTE;
1331 		if (!(pprint(pp, flag) & (PRUNNING | PSTOPPED)))
1332 		    pflush(pp);
1333 		break;
1334 	    }
1335 }
1336 
1337 /*
1338  * dofg - builtin - put the job into the foreground
1339  */
1340 /*ARGSUSED*/
1341 void
1342 dofg(Char **v, struct command *c)
1343 {
1344     struct process *pp;
1345 
1346     USE(c);
1347     okpcntl();
1348     ++v;
1349     do {
1350 	pp = pfind(*v);
1351 	if (!pstart(pp, 1)) {
1352 	    pp->p_procid = 0;
1353 	    stderror(ERR_NAME|ERR_BADJOB, pp->p_command, strerror(errno));
1354 	    continue;
1355 	}
1356 	pjwait(pp);
1357     } while (*v && *++v);
1358 }
1359 
1360 /*
1361  * %... - builtin - put the job into the foreground
1362  */
1363 /*ARGSUSED*/
1364 void
1365 dofg1(Char **v, struct command *c)
1366 {
1367     struct process *pp;
1368 
1369     USE(c);
1370     okpcntl();
1371     pp = pfind(v[0]);
1372     if (!pstart(pp, 1)) {
1373 	pp->p_procid = 0;
1374 	stderror(ERR_NAME|ERR_BADJOB, pp->p_command, strerror(errno));
1375 	return;
1376     }
1377     pjwait(pp);
1378 }
1379 
1380 /*
1381  * dobg - builtin - put the job into the background
1382  */
1383 /*ARGSUSED*/
1384 void
1385 dobg(Char **v, struct command *c)
1386 {
1387     struct process *pp;
1388 
1389     USE(c);
1390     okpcntl();
1391     ++v;
1392     do {
1393 	pp = pfind(*v);
1394 	if (!pstart(pp, 0)) {
1395 	    pp->p_procid = 0;
1396 	    stderror(ERR_NAME|ERR_BADJOB, pp->p_command, strerror(errno));
1397 	}
1398     } while (*v && *++v);
1399 }
1400 
1401 /*
1402  * %... & - builtin - put the job into the background
1403  */
1404 /*ARGSUSED*/
1405 void
1406 dobg1(Char **v, struct command *c)
1407 {
1408     struct process *pp;
1409 
1410     USE(c);
1411     pp = pfind(v[0]);
1412     if (!pstart(pp, 0)) {
1413 	pp->p_procid = 0;
1414 	stderror(ERR_NAME|ERR_BADJOB, pp->p_command, strerror(errno));
1415     }
1416 }
1417 
1418 /*
1419  * dostop - builtin - stop the job
1420  */
1421 /*ARGSUSED*/
1422 void
1423 dostop(Char **v, struct command *c)
1424 {
1425     USE(c);
1426 #ifdef BSDJOBS
1427     pkill(++v, SIGSTOP);
1428 #endif /* BSDJOBS */
1429 }
1430 
1431 /*
1432  * dokill - builtin - superset of kill (1)
1433  */
1434 /*ARGSUSED*/
1435 void
1436 dokill(Char **v, struct command *c)
1437 {
1438     int signum, len = 0;
1439     const char *name;
1440     Char *sigptr;
1441 
1442     USE(c);
1443     v++;
1444     if (v[0] && v[0][0] == '-') {
1445 	if (v[0][1] == 'l') {
1446 	    for (signum = 0; signum <= nsig; signum++) {
1447 		if ((name = mesg[signum].iname) != NULL) {
1448 		    len += strlen(name) + 1;
1449 		    if (len >= TermH - 1) {
1450 			xputchar('\n');
1451 			len = strlen(name) + 1;
1452 		    }
1453 		    xprintf("%s ", name);
1454 		}
1455 	    }
1456 	    xputchar('\n');
1457 	    return;
1458 	}
1459  	sigptr = &v[0][1];
1460  	if (v[0][1] == 's') {
1461  	    if (v[1]) {
1462  		v++;
1463  		sigptr = &v[0][0];
1464  	    } else {
1465  		stderror(ERR_NAME | ERR_TOOFEW);
1466  	    }
1467  	}
1468  	if (Isdigit(*sigptr)) {
1469 	    char *ep;
1470  	    signum = strtoul(short2str(sigptr), &ep, 0);
1471 	    if (*ep || signum < 0 || signum > (MAXSIG-1))
1472 		stderror(ERR_NAME | ERR_BADSIG);
1473 	}
1474 	else {
1475 	    for (signum = 0; signum <= nsig; signum++)
1476 		if (mesg[signum].iname &&
1477  		    eq(sigptr, str2short(mesg[signum].iname)))
1478 		    goto gotsig;
1479  	    setname(short2str(sigptr));
1480 	    stderror(ERR_NAME | ERR_UNKSIG);
1481 	}
1482 gotsig:
1483 	v++;
1484     }
1485     else
1486 	signum = SIGTERM;
1487     pkill(v, signum);
1488 }
1489 
1490 static void
1491 pkill(Char **v, int signum)
1492 {
1493     struct process *pp, *np;
1494     int jobflags = 0, err1 = 0;
1495     pid_t     pid;
1496     Char *cp, **vp, **globbed;
1497 
1498     /* Avoid globbing %?x patterns */
1499     for (vp = v; vp && *vp; vp++)
1500 	if (**vp == '%')
1501 	    (void) quote(*vp);
1502 
1503     v = glob_all_or_error(v);
1504     globbed = v;
1505     cleanup_push(globbed, blk_cleanup);
1506 
1507     pchild_disabled++;
1508     cleanup_push(&pchild_disabled, disabled_cleanup);
1509     if (setintr) {
1510 	pintr_disabled++;
1511 	cleanup_push(&pintr_disabled, disabled_cleanup);
1512     }
1513 
1514     while (v && (cp = *v)) {
1515 	if (*cp == '%') {
1516 	    np = pp = pfind(cp);
1517 	    do
1518 		jobflags |= np->p_flags;
1519 	    while ((np = np->p_friends) != pp);
1520 #ifdef BSDJOBS
1521 	    switch (signum) {
1522 
1523 	    case SIGSTOP:
1524 	    case SIGTSTP:
1525 	    case SIGTTIN:
1526 	    case SIGTTOU:
1527 		if ((jobflags & PRUNNING) == 0) {
1528 # ifdef SUSPENDED
1529 		    xprintf(CGETS(17, 12, "%S: Already suspended\n"), cp);
1530 # else /* !SUSPENDED */
1531 		    xprintf(CGETS(17, 13, "%S: Already stopped\n"), cp);
1532 # endif /* !SUSPENDED */
1533 		    err1++;
1534 		    goto cont;
1535 		}
1536 		break;
1537 		/*
1538 		 * suspend a process, kill -CONT %, then type jobs; the shell
1539 		 * says it is suspended, but it is running; thanks jaap..
1540 		 */
1541 	    case SIGCONT:
1542 		if (!pstart(pp, 0)) {
1543 		    pp->p_procid = 0;
1544 		    stderror(ERR_NAME|ERR_BADJOB, pp->p_command,
1545 			     strerror(errno));
1546 		}
1547 		goto cont;
1548 	    default:
1549 		break;
1550 	    }
1551 #endif /* BSDJOBS */
1552 	    if (killpg(pp->p_jobid, signum) < 0) {
1553 		xprintf("%S: %s\n", cp, strerror(errno));
1554 		err1++;
1555 	    }
1556 #ifdef BSDJOBS
1557 	    if (signum == SIGTERM || signum == SIGHUP)
1558 		(void) killpg(pp->p_jobid, SIGCONT);
1559 #endif /* BSDJOBS */
1560 	}
1561 	else if (!(Isdigit(*cp) || *cp == '-'))
1562 	    stderror(ERR_NAME | ERR_JOBARGS);
1563 	else {
1564 	    char *ep;
1565 #ifndef WINNT_NATIVE
1566 	    pid = strtol(short2str(cp), &ep, 10);
1567 #else
1568 	    pid = strtoul(short2str(cp), &ep, 0);
1569 #endif /* WINNT_NATIVE */
1570 	    if (*ep)
1571 		stderror(ERR_NAME | ERR_JOBARGS);
1572 	    else if (kill(pid, signum) < 0) {
1573 		xprintf("%d: %s\n", pid, strerror(errno));
1574 		err1++;
1575 		goto cont;
1576 	    }
1577 #ifdef BSDJOBS
1578 	    if (signum == SIGTERM || signum == SIGHUP)
1579 		(void) kill(pid, SIGCONT);
1580 #endif /* BSDJOBS */
1581 	}
1582 cont:
1583 	v++;
1584     }
1585     cleanup_until(&pchild_disabled);
1586     if (err1)
1587 	stderror(ERR_SILENT);
1588 }
1589 
1590 /*
1591  * pstart - start the job in foreground/background
1592  */
1593 int
1594 pstart(struct process *pp, int foregnd)
1595 {
1596     int rv = 0;
1597     struct process *np;
1598     /* We don't use jobflags in this function right now (see below) */
1599     /* long    jobflags = 0; */
1600 
1601     pchild_disabled++;
1602     cleanup_push(&pchild_disabled, disabled_cleanup);
1603     np = pp;
1604     do {
1605 	/* We don't use jobflags in this function right now (see below) */
1606 	/* jobflags |= np->p_flags; */
1607 	if (np->p_flags & (PRUNNING | PSTOPPED)) {
1608 	    np->p_flags |= PRUNNING;
1609 	    np->p_flags &= ~PSTOPPED;
1610 	    if (foregnd)
1611 		np->p_flags |= PFOREGND;
1612 	    else
1613 		np->p_flags &= ~PFOREGND;
1614 	}
1615     } while ((np = np->p_friends) != pp);
1616     if (!foregnd)
1617 	pclrcurr(pp);
1618     (void) pprint(pp, foregnd ? NAME | JOBDIR : NUMBER | NAME | AMPERSAND);
1619 
1620     /* GrP run jobcmd hook if foregrounding */
1621     if (foregnd) {
1622 	job_cmd(pp->p_command);
1623     }
1624 
1625 #ifdef BSDJOBS
1626     if (foregnd) {
1627 	rv = tcsetpgrp(FSHTTY, pp->p_jobid);
1628     }
1629     /*
1630      * 1. child process of csh (shell script) receives SIGTTIN/SIGTTOU
1631      * 2. parent process (csh) receives SIGCHLD
1632      * 3. The "csh" signal handling function pchild() is invoked
1633      *    with a SIGCHLD signal.
1634      * 4. pchild() calls wait3(WNOHANG) which returns 0.
1635      *    The child process is NOT ready to be waited for at this time.
1636      *    pchild() returns without picking-up the correct status
1637      *    for the child process which generated the SIGCHLD.
1638      * 5. CONSEQUENCE : csh is UNaware that the process is stopped
1639      * 6. THIS LINE HAS BEEN COMMENTED OUT : if (jobflags&PSTOPPED)
1640      * 	  (beto@aixwiz.austin.ibm.com - aug/03/91)
1641      * 7. I removed the line completely and added extra checks for
1642      *    pstart, so that if a job gets attached to and dies inside
1643      *    a debugger it does not confuse the shell. [christos]
1644      * 8. on the nec sx-4 there seems to be a problem, which requires
1645      *    a syscall(151, getpid(), getpid()) in osinit. Don't ask me
1646      *    what this is doing. [schott@rzg.mpg.de]
1647      */
1648 
1649     if (rv != -1)
1650 	rv = killpg(pp->p_jobid, SIGCONT);
1651 #endif /* BSDJOBS */
1652     cleanup_until(&pchild_disabled);
1653     return rv != -1;
1654 }
1655 
1656 void
1657 panystop(int neednl)
1658 {
1659     struct process *pp;
1660 
1661     chkstop = 2;
1662     for (pp = proclist.p_next; pp; pp = pp->p_next)
1663 	if (pp->p_flags & PSTOPPED)
1664 	    stderror(ERR_STOPPED, neednl ? "\n" : "");
1665 }
1666 
1667 struct process *
1668 pfind(Char *cp)
1669 {
1670     struct process *pp, *np;
1671 
1672     if (cp == 0 || cp[1] == 0 || eq(cp, STRcent2) || eq(cp, STRcentplus)) {
1673 	if (pcurrent == NULL)
1674 	    stderror(ERR_NAME | ERR_JOBCUR);
1675 	return (pcurrent);
1676     }
1677     if (eq(cp, STRcentminus) || eq(cp, STRcenthash)) {
1678 	if (pprevious == NULL)
1679 	    stderror(ERR_NAME | ERR_JOBPREV);
1680 	return (pprevious);
1681     }
1682     if (Isdigit(cp[1])) {
1683 	int     idx = atoi(short2str(cp + 1));
1684 
1685 	for (pp = proclist.p_next; pp; pp = pp->p_next)
1686 	    if (pp->p_index == idx && pp->p_procid == pp->p_jobid)
1687 		return (pp);
1688 	stderror(ERR_NAME | ERR_NOSUCHJOB);
1689     }
1690     np = NULL;
1691     for (pp = proclist.p_next; pp; pp = pp->p_next)
1692 	if (pp->p_procid == pp->p_jobid) {
1693 	    if (cp[1] == '?') {
1694 		Char *dp;
1695 
1696 		for (dp = pp->p_command; *dp; dp++) {
1697 		    if (*dp != cp[2])
1698 			continue;
1699 		    if (prefix(cp + 2, dp))
1700 			goto match;
1701 		}
1702 	    }
1703 	    else if (prefix(cp + 1, pp->p_command)) {
1704 	match:
1705 		if (np)
1706 		    stderror(ERR_NAME | ERR_AMBIG);
1707 		np = pp;
1708 	    }
1709 	}
1710     if (np)
1711 	return (np);
1712     stderror(ERR_NAME | (cp[1] == '?' ? ERR_JOBPAT : ERR_NOSUCHJOB));
1713     /* NOTREACHED */
1714     return (0);
1715 }
1716 
1717 
1718 /*
1719  * pgetcurr - find most recent job that is not pp, preferably stopped
1720  */
1721 static struct process *
1722 pgetcurr(struct process *pp)
1723 {
1724     struct process *np;
1725     struct process *xp = NULL;
1726 
1727     for (np = proclist.p_next; np; np = np->p_next)
1728 	if (np != pcurrent && np != pp && np->p_procid &&
1729 	    np->p_procid == np->p_jobid) {
1730 	    if (np->p_flags & PSTOPPED)
1731 		return (np);
1732 	    if (xp == NULL)
1733 		xp = np;
1734 	}
1735     return (xp);
1736 }
1737 
1738 /*
1739  * donotify - flag the job so as to report termination asynchronously
1740  */
1741 /*ARGSUSED*/
1742 void
1743 donotify(Char **v, struct command *c)
1744 {
1745     struct process *pp;
1746 
1747     USE(c);
1748     pp = pfind(*++v);
1749     pp->p_flags |= PNOTIFY;
1750 }
1751 
1752 #ifdef SIGSYNCH
1753 static void
1754 synch_handler(int sno)
1755 {
1756     USE(sno);
1757 }
1758 #endif /* SIGSYNCH */
1759 
1760 /*
1761  * Do the fork and whatever should be done in the child side that
1762  * should not be done if we are not forking at all (like for simple builtin's)
1763  * Also do everything that needs any signals fiddled with in the parent side
1764  *
1765  * Wanttty tells whether process and/or tty pgrps are to be manipulated:
1766  *	-1:	leave tty alone; inherit pgrp from parent
1767  *	 0:	already have tty; manipulate process pgrps only
1768  *	 1:	want to claim tty; manipulate process and tty pgrps
1769  * It is usually just the value of tpgrp.
1770  */
1771 
1772 pid_t
1773 pfork(struct command *t, int wanttty)
1774 {
1775     pid_t pid;
1776     int    ignint = 0;
1777     pid_t pgrp;
1778 #ifdef SIGSYNCH
1779     struct sigaction osa, nsa;
1780 #endif /* SIGSYNCH */
1781 
1782     /*
1783      * A child will be uninterruptible only under very special conditions.
1784      * Remember that the semantics of '&' is implemented by disconnecting the
1785      * process from the tty so signals do not need to ignored just for '&'.
1786      * Thus signals are set to default action for children unless: we have had
1787      * an "onintr -" (then specifically ignored) we are not playing with
1788      * signals (inherit action)
1789      */
1790     if (setintr)
1791 	ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT))
1792 	    || (gointr && eq(gointr, STRminus));
1793 
1794     /*
1795      * Check for maximum nesting of 16 processes to avoid Forking loops
1796      */
1797     if (child == 16)
1798 	stderror(ERR_NESTING, 16);
1799 #ifdef SIGSYNCH
1800     nsa.sa_handler = synch_handler;
1801     sigfillset(&nsa.sa_mask);
1802     nsa.sa_flags = SA_RESTART;
1803     if (sigaction(SIGSYNCH, &nsa, &osa))
1804 	stderror(ERR_SYSTEM, "pfork: sigaction set", strerror(errno));
1805 #endif /* SIGSYNCH */
1806     /*
1807      * Hold pchild() until we have the process installed in our table.
1808      */
1809     if (wanttty < 0) {
1810 	pchild_disabled++;
1811 	cleanup_push(&pchild_disabled, disabled_cleanup);
1812     }
1813     while ((pid = fork()) == -1)
1814 	if (setintr == 0)
1815 	    (void) sleep(FORKSLEEP);
1816 	else
1817 	    stderror(ERR_NOPROC);
1818     if (pid == 0) {
1819 	(void)cleanup_push_mark(); /* Never to be popped */
1820 	pchild_disabled = 0;
1821 	settimes();
1822 	pgrp = pcurrjob ? pcurrjob->p_jobid : getpid();
1823 	pflushall();
1824 	pcurrjob = NULL;
1825 #if !defined(BSDTIMES) && !defined(_SEQUENT_)
1826 	timesdone = 0;
1827 #endif /* !defined(BSDTIMES) && !defined(_SEQUENT_) */
1828 	child++;
1829 	if (setintr) {
1830 	    setintr = 0;	/* until I think otherwise */
1831 	    /*
1832 	     * Children just get blown away on SIGINT, SIGQUIT unless "onintr
1833 	     * -" seen.
1834 	     */
1835 	    (void) signal(SIGINT, ignint ? SIG_IGN : SIG_DFL);
1836 	    (void) signal(SIGQUIT, ignint ? SIG_IGN : SIG_DFL);
1837 #ifdef BSDJOBS
1838 	    if (wanttty >= 0) {
1839 		/* make stoppable */
1840 		(void) signal(SIGTSTP, SIG_DFL);
1841 		(void) signal(SIGTTIN, SIG_DFL);
1842 		(void) signal(SIGTTOU, SIG_DFL);
1843 	    }
1844 #endif /* BSDJOBS */
1845 	    sigaction(SIGTERM, &parterm, NULL);
1846 	}
1847 	else if (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT)) {
1848 	    (void) signal(SIGINT, SIG_IGN);
1849 	    (void) signal(SIGQUIT, SIG_IGN);
1850 	}
1851 #ifdef OREO
1852 	signal(SIGIO, SIG_IGN);	/* ignore SIGIO in child too */
1853 #endif /* OREO */
1854 
1855 	pgetty(wanttty, pgrp);
1856 	/*
1857 	 * Nohup and nice apply only to NODE_COMMAND's but it would be nice
1858 	 * (?!?) if you could say "nohup (foo;bar)" Then the parser would have
1859 	 * to know about nice/nohup/time
1860 	 */
1861 	if (t->t_dflg & F_NOHUP)
1862 	    (void) signal(SIGHUP, SIG_IGN);
1863 	if (t->t_dflg & F_NICE) {
1864 	    int nval = SIGN_EXTEND_CHAR(t->t_nice);
1865 #if defined(HAVE_SETPRIORITY) && defined(PRIO_PROCESS)
1866 	    if (setpriority(PRIO_PROCESS, 0, nval) == -1 && errno)
1867 		stderror(ERR_SYSTEM, "setpriority", strerror(errno));
1868 #else /* !HAVE_SETPRIORITY || !PRIO_PROCESS */
1869 	    (void) nice(nval);
1870 #endif /* HAVE_SETPRIORITY  && PRIO_PROCESS */
1871 	}
1872 #ifdef F_VER
1873         if (t->t_dflg & F_VER) {
1874 	    tsetenv(STRSYSTYPE, t->t_systype ? STRbsd43 : STRsys53);
1875 	    dohash(NULL, NULL);
1876 	}
1877 #endif /* F_VER */
1878 #ifdef SIGSYNCH
1879 	/* rfw 8/89 now parent can continue */
1880 	if (kill(getppid(), SIGSYNCH))
1881 	    stderror(ERR_SYSTEM, "pfork child: kill", strerror(errno));
1882 #endif /* SIGSYNCH */
1883 
1884     }
1885     else {
1886 #ifdef POSIXJOBS
1887         if (wanttty >= 0) {
1888 	    /*
1889 	     * `Walking' process group fix from Beto Appleton.
1890 	     * (beto@aixwiz.austin.ibm.com)
1891 	     * If setpgid fails at this point that means that
1892 	     * our process leader has died. We flush the current
1893 	     * job and become the process leader ourselves.
1894 	     * The parent will figure that out later.
1895 	     */
1896 	    pgrp = pcurrjob ? pcurrjob->p_jobid : pid;
1897 	    if (setpgid(pid, pgrp) == -1 && errno == EPERM) {
1898 		pcurrjob = NULL;
1899 		/*
1900 		 * We don't care if this causes an error here;
1901 		 * then we are already in the right process group
1902 		 */
1903 		(void) setpgid(pid, pgrp = pid);
1904 	    }
1905 	}
1906 #endif /* POSIXJOBS */
1907 	palloc(pid, t);
1908 #ifdef SIGSYNCH
1909 	{
1910 	    sigset_t pause_mask;
1911 
1912 	/*
1913 	 * rfw 8/89 Wait for child to own terminal.  Solves half of ugly
1914 	 * synchronization problem.  With this change, we know that the only
1915 	 * reason setpgrp to a previous process in a pipeline can fail is that
1916 	 * the previous process has already exited. Without this hack, he may
1917 	 * either have exited or not yet started to run.  Two uglies become
1918 	 * one.
1919 	 */
1920 	    sigprocmask(SIG_BLOCK, NULL, &pause);
1921 	    sigdelset(&pause_mask, SIGCHLD);
1922 	    sigdelset(&pause_mask, SIGSYNCH);
1923 	    sigsuspend(&pause_mask);
1924 	    (void)handle_pending_signals();
1925 	    if (sigaction(SIGSYNCH, &osa, NULL))
1926 		stderror(ERR_SYSTEM, "pfork parent: sigaction restore",
1927 			 strerror(errno));
1928 	}
1929 #endif /* SIGSYNCH */
1930 
1931 	if (wanttty < 0)
1932 	    cleanup_until(&pchild_disabled);
1933     }
1934     return (pid);
1935 }
1936 
1937 static void
1938 okpcntl(void)
1939 {
1940     if (tpgrp == -1)
1941 	stderror(ERR_JOBCONTROL);
1942     if (tpgrp == 0)
1943 	stderror(ERR_JOBCTRLSUB);
1944 }
1945 
1946 
1947 static void
1948 setttypgrp(int pgrp)
1949 {
1950     /*
1951      * If we are piping out a builtin, eg. 'echo | more' things can go
1952      * out of sequence, i.e. the more can run before the echo. This
1953      * can happen even if we have vfork, since the echo will be forked
1954      * with the regular fork. In this case, we need to set the tty
1955      * pgrp ourselves. If that happens, then the process will be still
1956      * alive. And the tty process group will already be set.
1957      * This should fix the famous sequent problem as a side effect:
1958      *    The controlling terminal is lost if all processes in the
1959      *    terminal process group are zombies. In this case tcgetpgrp()
1960      *    returns 0. If this happens we must set the terminal process
1961      *    group again.
1962      */
1963     if (tcgetpgrp(FSHTTY) != pgrp) {
1964 #ifdef POSIXJOBS
1965 	struct sigaction old;
1966 
1967         /*
1968 	 * tcsetpgrp will set SIGTTOU to all the the processes in
1969 	 * the background according to POSIX... We ignore this here.
1970 	 */
1971 	sigaction(SIGTTOU, NULL, &old);
1972 	signal(SIGTTOU, SIG_IGN);
1973 #endif
1974 	(void) tcsetpgrp(FSHTTY, pgrp);
1975 # ifdef POSIXJOBS
1976 	sigaction(SIGTTOU, &old, NULL);
1977 # endif
1978 
1979     }
1980 }
1981 
1982 
1983 /*
1984  * if we don't have vfork(), things can still go in the wrong order
1985  * resulting in the famous 'Stopped (tty output)'. But some systems
1986  * don't permit the setpgid() call, (these are more recent secure
1987  * systems such as ibm's aix), when they do. Then we'd rather print
1988  * an error message than hang the shell!
1989  * I am open to suggestions how to fix that.
1990  */
1991 void
1992 pgetty(int wanttty, pid_t pgrp)
1993 {
1994 #ifdef BSDJOBS
1995 # ifdef POSIXJOBS
1996     sigset_t oset, set;
1997 # endif /* POSIXJOBS */
1998 
1999     jobdebug_xprintf(("wanttty %d pid %d opgrp%d pgrp %d tpgrp %d\n",
2000 		      wanttty, (int)getpid(), (int)pgrp, (int)mygetpgrp(),
2001 		      (int)tcgetpgrp(FSHTTY)));
2002 # ifdef POSIXJOBS
2003     /*
2004      * christos: I am blocking the tty signals till I've set things
2005      * correctly....
2006      */
2007     if (wanttty > 0) {
2008 	sigemptyset(&set);
2009 	sigaddset(&set, SIGTSTP);
2010 	sigaddset(&set, SIGTTIN);
2011 	(void)sigprocmask(SIG_BLOCK, &set, &oset);
2012 	cleanup_push(&oset, sigprocmask_cleanup);
2013     }
2014 # endif /* POSIXJOBS */
2015 
2016 # ifndef POSIXJOBS
2017     if (wanttty > 0)
2018 	setttypgrp(pgrp);
2019 # endif /* !POSIXJOBS */
2020 
2021     /*
2022      * From: Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de>
2023      * Don't check for tpgrp >= 0 so even non-interactive shells give
2024      * background jobs process groups Same for the comparison in the other part
2025      * of the #ifdef
2026      */
2027     if (wanttty >= 0) {
2028 	if (setpgid(0, pgrp) == -1) {
2029 # ifdef POSIXJOBS
2030 	    /* Walking process group fix; see above */
2031 	    if (setpgid(0, pgrp = getpid()) == -1) {
2032 # endif /* POSIXJOBS */
2033 		stderror(ERR_SYSTEM, "setpgid child:\n", strerror(errno));
2034 		xexit(0);
2035 # ifdef POSIXJOBS
2036 	    }
2037 	    wanttty = pgrp;  /* Now we really want the tty, since we became the
2038 			      * the process group leader
2039 			      */
2040 # endif /* POSIXJOBS */
2041 	}
2042     }
2043 
2044 # ifdef POSIXJOBS
2045     if (wanttty > 0) {
2046 	setttypgrp(pgrp);
2047 	cleanup_until(&oset);
2048     }
2049 # endif /* POSIXJOBS */
2050 
2051     jobdebug_xprintf(("wanttty %d pid %d pgrp %d tpgrp %d\n",
2052 		      wanttty, getpid(), mygetpgrp(), tcgetpgrp(FSHTTY)));
2053 
2054     if (tpgrp > 0)
2055 	tpgrp = 0;		/* gave tty away */
2056 #endif /* BSDJOBS */
2057 }
2058