xref: /netbsd/bin/csh/proc.c (revision 889e6b05)
1 /* $NetBSD: proc.c,v 1.42 2021/09/16 19:34:21 christos Exp $ */
2 
3 /*-
4  * Copyright (c) 1980, 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)proc.c	8.1 (Berkeley) 5/31/93";
36 #else
37 __RCSID("$NetBSD: proc.c,v 1.42 2021/09/16 19:34:21 christos Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include <sys/types.h>
42 #include <sys/wait.h>
43 
44 #include <errno.h>
45 #include <stdarg.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "csh.h"
51 #include "dir.h"
52 #include "extern.h"
53 #include "proc.h"
54 
55 #define BIGINDEX 9 /* largest desirable job index */
56 
57 extern int insource;
58 
59 struct process proclist;
60 int pnoprocesses;
61 
62 struct process *pholdjob;
63 
64 struct process *pcurrjob;
65 struct process *pcurrent;
66 struct process *pprevious;
67 
68 int pmaxindex;
69 
70 static void pflushall(void);
71 static void pflush(struct process *);
72 static void pclrcurr(struct process *);
73 static void padd(struct command *);
74 static int pprint(struct process *, int);
75 static void ptprint(struct process *);
76 static void pads(Char *);
77 static void pkill(Char **v, int);
78 static struct process *pgetcurr(struct process *);
79 static void okpcntl(void);
80 
81 /*
82  * pchild - called at interrupt level by the SIGCHLD signal
83  *	indicating that at least one child has terminated or stopped
84  *	thus at least one wait system call will definitely return a
85  *	childs status.  Top level routines (like pwait) must be sure
86  *	to mask interrupts when playing with the proclist data structures!
87  */
88 /* ARGSUSED */
89 void
pchild(int notused)90 pchild(int notused)
91 {
92     struct rusage ru;
93     struct process *fp, *pp;
94     int jobflags, pid, w;
95 
96 loop:
97     errno = 0;			/* reset, just in case */
98     pid = wait3(&w,
99        (setintr && (intty || insource) ? WNOHANG | WUNTRACED : WNOHANG), &ru);
100 
101     if (pid <= 0) {
102 	if (errno == EINTR) {
103 	    errno = 0;
104 	    goto loop;
105 	}
106 	pnoprocesses = pid == -1;
107 	return;
108     }
109     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next)
110 	if (pid == pp->p_pid)
111 	    goto found;
112     goto loop;
113 found:
114     if (pid == atoi(short2str(value(STRchild))))
115 	unsetv(STRchild);
116     pp->p_flags &= ~(PRUNNING | PSTOPPED | PREPORTED);
117     if (WIFSTOPPED(w)) {
118 	pp->p_flags |= PSTOPPED;
119 	pp->p_reason = WSTOPSIG(w);
120     }
121     else {
122 	if (pp->p_flags & (PTIME | PPTIME) || adrof(STRtime))
123 	    (void)clock_gettime(CLOCK_MONOTONIC, &pp->p_etime);
124 
125 	pp->p_rusage = ru;
126 	if (WIFSIGNALED(w)) {
127 	    if (WTERMSIG(w) == SIGINT)
128 		pp->p_flags |= PINTERRUPTED;
129 	    else
130 		pp->p_flags |= PSIGNALED;
131 	    if (WCOREDUMP(w))
132 		pp->p_flags |= PDUMPED;
133 	    pp->p_reason = WTERMSIG(w);
134 	}
135 	else {
136 	    pp->p_reason = WEXITSTATUS(w);
137 	    if (pp->p_reason != 0)
138 		pp->p_flags |= PAEXITED;
139 	    else
140 		pp->p_flags |= PNEXITED;
141 	}
142     }
143     jobflags = 0;
144     fp = pp;
145     do {
146 	if ((fp->p_flags & (PPTIME | PRUNNING | PSTOPPED)) == 0 &&
147 	    !child && adrof(STRtime) &&
148 	    fp->p_rusage.ru_utime.tv_sec + fp->p_rusage.ru_stime.tv_sec
149 	    >= atoi(short2str(value(STRtime))))
150 	    fp->p_flags |= PTIME;
151 	jobflags |= fp->p_flags;
152     } while ((fp = fp->p_friends) != pp);
153     pp->p_flags &= ~PFOREGND;
154     if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
155 	pp->p_flags &= ~PPTIME;
156 	pp->p_flags |= PTIME;
157     }
158     if ((jobflags & (PRUNNING | PREPORTED)) == 0) {
159 	fp = pp;
160 	do {
161 	    if (fp->p_flags & PSTOPPED)
162 		fp->p_flags |= PREPORTED;
163 	} while ((fp = fp->p_friends) != pp);
164 	while (fp->p_pid != fp->p_jobid)
165 	    fp = fp->p_friends;
166 	if (jobflags & PSTOPPED) {
167 	    if (pcurrent && pcurrent != fp)
168 		pprevious = pcurrent;
169 	    pcurrent = fp;
170 	}
171 	else
172 	    pclrcurr(fp);
173 	if (jobflags & PFOREGND) {
174 	    if (jobflags & (PSIGNALED | PSTOPPED | PPTIME) ||
175 #ifdef IIASA
176 		jobflags & PAEXITED ||
177 #endif
178 		!eq(dcwd->di_name, fp->p_cwd->di_name)) {
179 		;		/* print in pjwait */
180 	    }
181 	    /* PWP: print a newline after ^C */
182 	    else if (jobflags & PINTERRUPTED) {
183 		(void)vis_fputc('\r' | QUOTE, cshout);
184 		(void)fputc('\n', cshout);
185 	    }
186 	}
187 	else {
188 	    if (jobflags & PNOTIFY || adrof(STRnotify)) {
189 		(void)vis_fputc('\r' | QUOTE, cshout);
190 		(void)fputc('\n', cshout);
191 		(void)pprint(pp, NUMBER | NAME | REASON);
192 		if ((jobflags & PSTOPPED) == 0)
193 		    pflush(pp);
194 	    }
195 	    else {
196 		fp->p_flags |= PNEEDNOTE;
197 		neednote++;
198 	    }
199 	}
200     }
201     goto loop;
202 }
203 
204 void
pnote(void)205 pnote(void)
206 {
207     struct process *pp;
208     sigset_t osigset, nsigset;
209     int flags;
210 
211     neednote = 0;
212     sigemptyset(&nsigset);
213     (void)sigaddset(&nsigset, SIGCHLD);
214     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next) {
215 	if (pp->p_flags & PNEEDNOTE) {
216 	    (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
217 	    pp->p_flags &= ~PNEEDNOTE;
218 	    flags = pprint(pp, NUMBER | NAME | REASON);
219 	    if ((flags & (PRUNNING | PSTOPPED)) == 0)
220 		pflush(pp);
221 	    (void)sigprocmask(SIG_SETMASK, &osigset, NULL);
222 	}
223     }
224 }
225 
226 /*
227  * pwait - wait for current job to terminate, maintaining integrity
228  *	of current and previous job indicators.
229  */
230 void
pwait(void)231 pwait(void)
232 {
233     struct process *fp, *pp;
234     sigset_t osigset, nsigset;
235 
236     /*
237      * Here's where dead procs get flushed.
238      */
239     sigemptyset(&nsigset);
240     (void)sigaddset(&nsigset, SIGCHLD);
241     (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
242     for (pp = (fp = &proclist)->p_next; pp != NULL; pp = (fp = pp)->p_next)
243 	if (pp->p_pid == 0) {
244 	    fp->p_next = pp->p_next;
245 	    free(pp->p_command);
246 	    if (pp->p_cwd && --pp->p_cwd->di_count == 0)
247 		if (pp->p_cwd->di_next == 0)
248 		    dfree(pp->p_cwd);
249 	    free(pp);
250 	    pp = fp;
251 	}
252     (void)sigprocmask(SIG_SETMASK, &osigset, NULL);
253     pjwait(pcurrjob);
254 }
255 
256 
257 /*
258  * pjwait - wait for a job to finish or become stopped
259  *	It is assumed to be in the foreground state (PFOREGND)
260  */
261 void
pjwait(struct process * pp)262 pjwait(struct process *pp)
263 {
264     struct process *fp;
265     sigset_t osigset, nsigset;
266     int jobflags, reason;
267 
268     while (pp->p_pid != pp->p_jobid)
269 	pp = pp->p_friends;
270     fp = pp;
271 
272     do {
273 	if ((fp->p_flags & (PFOREGND | PRUNNING)) == PRUNNING)
274 	    (void)fprintf(csherr, "BUG: waiting for background job!\n");
275     } while ((fp = fp->p_friends) != pp);
276     /*
277      * Now keep pausing as long as we are not interrupted (SIGINT), and the
278      * target process, or any of its friends, are running
279      */
280     fp = pp;
281     sigemptyset(&nsigset);
282     (void)sigaddset(&nsigset, SIGCHLD);
283     (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
284     for (;;) {
285 	sigemptyset(&nsigset);
286 	(void)sigaddset(&nsigset, SIGCHLD);
287 	(void)sigprocmask(SIG_BLOCK, &nsigset, NULL);
288 	jobflags = 0;
289 	do
290 	    jobflags |= fp->p_flags;
291 	while ((fp = (fp->p_friends)) != pp);
292 	if ((jobflags & PRUNNING) == 0)
293 	    break;
294 #ifdef JOBDEBUG
295 	(void)fprintf(csherr, "starting to sigsuspend for  SIGCHLD on %d\n",
296 		       fp->p_pid);
297 #endif				/* JOBDEBUG */
298 	nsigset = osigset;
299 	(void)sigdelset(&nsigset, SIGCHLD);
300 	(void)sigsuspend(&nsigset);
301     }
302     (void)sigprocmask(SIG_SETMASK, &osigset, NULL);
303     if (tpgrp > 0)		/* get tty back */
304 	(void)tcsetpgrp(FSHTTY, tpgrp);
305     if ((jobflags & (PSIGNALED | PSTOPPED | PTIME)) ||
306 	!eq(dcwd->di_name, fp->p_cwd->di_name)) {
307 	if (jobflags & PSTOPPED) {
308 	    (void) fputc('\n', cshout);
309 	    if (adrof(STRlistjobs)) {
310 		Char *jobcommand[3];
311 
312 		jobcommand[0] = STRjobs;
313 		if (eq(value(STRlistjobs), STRlong))
314 		    jobcommand[1] = STRml;
315 		else
316 		    jobcommand[1] = NULL;
317 		jobcommand[2] = NULL;
318 
319 		dojobs(jobcommand, NULL);
320 		(void)pprint(pp, SHELLDIR);
321 	    }
322 	    else
323 		(void)pprint(pp, AREASON | SHELLDIR);
324 	}
325 	else
326 	    (void)pprint(pp, AREASON | SHELLDIR);
327     }
328     if ((jobflags & (PINTERRUPTED | PSTOPPED)) && setintr &&
329 	(!gointr || !eq(gointr, STRminus))) {
330 	if ((jobflags & PSTOPPED) == 0)
331 	    pflush(pp);
332 	pintr1(0);
333     }
334     reason = 0;
335     fp = pp;
336     do {
337 	if (fp->p_reason)
338 	    reason = fp->p_flags & (PSIGNALED | PINTERRUPTED) ?
339 		fp->p_reason | META : fp->p_reason;
340     } while ((fp = fp->p_friends) != pp);
341     if ((reason != 0) && (adrof(STRprintexitvalue))) {
342 	(void)fprintf(cshout, "Exit %d\n", reason);
343     }
344     set(STRstatus, putn(reason));
345     if (reason && exiterr)
346 	exitstat();
347     pflush(pp);
348 }
349 
350 /*
351  * dowait - wait for all processes to finish
352  */
353 void
354 /*ARGSUSED*/
dowait(Char ** v,struct command * t)355 dowait(Char **v, struct command *t)
356 {
357     struct process *pp;
358     sigset_t osigset, nsigset;
359 
360     pjobs++;
361     sigemptyset(&nsigset);
362     (void)sigaddset(&nsigset, SIGCHLD);
363     (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
364 loop:
365     for (pp = proclist.p_next; pp; pp = pp->p_next)
366 	if (pp->p_pid &&	/* pp->p_pid == pp->p_jobid && */
367 	    pp->p_flags & PRUNNING) {
368 	    sigemptyset(&nsigset);
369 	    (void)sigsuspend(&nsigset);
370 	    goto loop;
371 	}
372     (void)sigprocmask(SIG_SETMASK, &osigset, NULL);
373     pjobs = 0;
374 }
375 
376 /*
377  * pflushall - flush all jobs from list (e.g. at fork())
378  */
379 static void
pflushall(void)380 pflushall(void)
381 {
382     struct process *pp;
383 
384     for (pp = proclist.p_next; pp != NULL; pp = pp->p_next)
385 	if (pp->p_pid)
386 	    pflush(pp);
387 }
388 
389 /*
390  * pflush - flag all process structures in the same job as the
391  *	the argument process for deletion.  The actual free of the
392  *	space is not done here since pflush is called at interrupt level.
393  */
394 static void
pflush(struct process * pp)395 pflush(struct process *pp)
396 {
397     struct process *np;
398     int idx;
399 
400     if (pp->p_pid == 0) {
401 	(void)fprintf(csherr, "BUG: process flushed twice");
402 	return;
403     }
404     while (pp->p_pid != pp->p_jobid)
405 	pp = pp->p_friends;
406     pclrcurr(pp);
407     if (pp == pcurrjob)
408 	pcurrjob = 0;
409     idx = pp->p_index;
410     np = pp;
411     do {
412 	np->p_index = np->p_pid = 0;
413 	np->p_flags &= ~PNEEDNOTE;
414     } while ((np = np->p_friends) != pp);
415     if (idx == pmaxindex) {
416 	for (np = proclist.p_next, idx = 0; np; np = np->p_next)
417 	    if (np->p_index > idx)
418 		idx = np->p_index;
419 	pmaxindex = idx;
420     }
421 }
422 
423 /*
424  * pclrcurr - make sure the given job is not the current or previous job;
425  *	pp MUST be the job leader
426  */
427 static void
pclrcurr(struct process * pp)428 pclrcurr(struct process *pp)
429 {
430     if (pp == pcurrent) {
431 	if (pprevious != NULL) {
432 	    pcurrent = pprevious;
433 	    pprevious = pgetcurr(pp);
434 	}
435 	else {
436 	    pcurrent = pgetcurr(pp);
437 	    pprevious = pgetcurr(pp);
438 	}
439     } else if (pp == pprevious)
440 	pprevious = pgetcurr(pp);
441 }
442 
443 /* +4 here is 1 for '\0', 1 ea for << >& >> */
444 static Char command[PMAXLEN + 4];
445 static size_t cmdlen;
446 static Char *cmdp;
447 
448 /*
449  * palloc - allocate a process structure and fill it up.
450  *	an important assumption is made that the process is running.
451  */
452 void
palloc(int pid,struct command * t)453 palloc(int pid, struct command *t)
454 {
455     struct process *pp;
456     int i;
457 
458     pp = xcalloc(1, sizeof(*pp));
459     pp->p_pid = pid;
460     pp->p_flags = t->t_dflg & F_AMPERSAND ? PRUNNING : PRUNNING | PFOREGND;
461     if (t->t_dflg & F_TIME)
462 	pp->p_flags |= PPTIME;
463     cmdp = command;
464     cmdlen = 0;
465     padd(t);
466     *cmdp++ = 0;
467     if (t->t_dflg & F_PIPEOUT) {
468 	pp->p_flags |= PPOU;
469 	if (t->t_dflg & F_STDERR)
470 	    pp->p_flags |= PERR;
471     }
472     pp->p_command = Strsave(command);
473     if (pcurrjob) {
474 	struct process *fp;
475 
476 	/* careful here with interrupt level */
477 	pp->p_cwd = 0;
478 	pp->p_index = pcurrjob->p_index;
479 	pp->p_friends = pcurrjob;
480 	pp->p_jobid = pcurrjob->p_pid;
481 	for (fp = pcurrjob; fp->p_friends != pcurrjob; fp = fp->p_friends)
482 	    continue;
483 	fp->p_friends = pp;
484     }
485     else {
486 	pcurrjob = pp;
487 	pp->p_jobid = pid;
488 	pp->p_friends = pp;
489 	pp->p_cwd = dcwd;
490 	dcwd->di_count++;
491 	if (pmaxindex < BIGINDEX)
492 	    pp->p_index = ++pmaxindex;
493 	else {
494 	    struct process *np;
495 
496 	    for (i = 1;; i++) {
497 		for (np = proclist.p_next; np; np = np->p_next)
498 		    if (np->p_index == i)
499 			goto tryagain;
500 		pp->p_index = i;
501 		if (i > pmaxindex)
502 		    pmaxindex = i;
503 		break;
504 	tryagain:;
505 	    }
506 	}
507 	if (pcurrent == NULL)
508 	    pcurrent = pp;
509 	else if (pprevious == NULL)
510 	    pprevious = pp;
511     }
512     pp->p_next = proclist.p_next;
513     proclist.p_next = pp;
514     (void)clock_gettime(CLOCK_MONOTONIC, &pp->p_btime);
515 }
516 
517 static void
padd(struct command * t)518 padd(struct command *t)
519 {
520     Char **argp;
521 
522     if (t == 0)
523 	return;
524     switch (t->t_dtyp) {
525     case NODE_PAREN:
526 	pads(STRLparensp);
527 	padd(t->t_dspr);
528 	pads(STRspRparen);
529 	break;
530     case NODE_COMMAND:
531 	for (argp = t->t_dcom; *argp; argp++) {
532 	    pads(*argp);
533 	    if (argp[1])
534 		pads(STRspace);
535 	}
536 	break;
537     case NODE_OR:
538     case NODE_AND:
539     case NODE_PIPE:
540     case NODE_LIST:
541 	padd(t->t_dcar);
542 	switch (t->t_dtyp) {
543 	case NODE_OR:
544 	    pads(STRspor2sp);
545 	    break;
546 	case NODE_AND:
547 	    pads(STRspand2sp);
548 	    break;
549 	case NODE_PIPE:
550 	    pads(STRsporsp);
551 	    break;
552 	case NODE_LIST:
553 	    pads(STRsemisp);
554 	    break;
555 	}
556 	padd(t->t_dcdr);
557 	return;
558     }
559     if ((t->t_dflg & F_PIPEIN) == 0 && t->t_dlef) {
560 	pads((t->t_dflg & F_READ) ? STRspLarrow2sp : STRspLarrowsp);
561 	pads(t->t_dlef);
562     }
563     if ((t->t_dflg & F_PIPEOUT) == 0 && t->t_drit) {
564 	pads((t->t_dflg & F_APPEND) ? STRspRarrow2 : STRspRarrow);
565 	if (t->t_dflg & F_STDERR)
566 	    pads(STRand);
567 	pads(STRspace);
568 	pads(t->t_drit);
569     }
570 }
571 
572 static void
pads(Char * cp)573 pads(Char *cp)
574 {
575     size_t i;
576 
577     /*
578      * Avoid the Quoted Space alias hack! Reported by:
579      * sam@john-bigboote.ICS.UCI.EDU (Sam Horrocks)
580      */
581     if (cp[0] == STRQNULL[0])
582 	cp++;
583 
584     i = Strlen(cp);
585 
586     if (cmdlen >= PMAXLEN)
587 	return;
588     if (cmdlen + i >= PMAXLEN) {
589 	(void)Strcpy(cmdp, STRsp3dots);
590 	cmdlen = PMAXLEN;
591 	cmdp += 4;
592 	return;
593     }
594     (void)Strcpy(cmdp, cp);
595     cmdp += i;
596     cmdlen += i;
597 }
598 
599 /*
600  * psavejob - temporarily save the current job on a one level stack
601  *	so another job can be created.  Used for { } in exp6
602  *	and `` in globbing.
603  */
604 void
psavejob(void)605 psavejob(void)
606 {
607     pholdjob = pcurrjob;
608     pcurrjob = NULL;
609 }
610 
611 /*
612  * prestjob - opposite of psavejob.  This may be missed if we are interrupted
613  *	somewhere, but pendjob cleans up anyway.
614  */
615 void
prestjob(void)616 prestjob(void)
617 {
618     pcurrjob = pholdjob;
619     pholdjob = NULL;
620 }
621 
622 /*
623  * pendjob - indicate that a job (set of commands) has been completed
624  *	or is about to begin.
625  */
626 void
pendjob(void)627 pendjob(void)
628 {
629     struct process *pp, *tp;
630 
631     if (pcurrjob && (pcurrjob->p_flags & (PFOREGND | PSTOPPED)) == 0) {
632 	pp = pcurrjob;
633 	while (pp->p_pid != pp->p_jobid)
634 	    pp = pp->p_friends;
635 	(void)fprintf(cshout, "[%d]", pp->p_index);
636 	tp = pp;
637 	do {
638 	    (void)fprintf(cshout, " %ld", (long)pp->p_pid);
639 	    pp = pp->p_friends;
640 	} while (pp != tp);
641 	(void)fputc('\n', cshout);
642     }
643     pholdjob = pcurrjob = 0;
644 }
645 
646 /*
647  * pprint - print a job
648  */
649 static int
pprint(struct process * pp,int flag)650 pprint(struct process *pp, int flag)
651 {
652     static struct rusage zru;
653     struct process *tp;
654     const char *format;
655     int jobflags, pstatus, reason, status;
656     int hadnl;
657 
658     hadnl = 1; /* did we just have a newline */
659     (void)fpurge(cshout);
660 
661     while (pp->p_pid != pp->p_jobid)
662 	pp = pp->p_friends;
663     if (pp == pp->p_friends && (pp->p_flags & PPTIME)) {
664 	pp->p_flags &= ~PPTIME;
665 	pp->p_flags |= PTIME;
666     }
667     tp = pp;
668     status = reason = -1;
669     jobflags = 0;
670     do {
671 	jobflags |= pp->p_flags;
672 	pstatus = pp->p_flags & PALLSTATES;
673 	if (tp != pp && !hadnl && !(flag & FANCY) &&
674 	    ((pstatus == status && pp->p_reason == reason) ||
675 	     !(flag & REASON))) {
676 	    (void)fputc(' ', cshout);
677 	    hadnl = 0;
678 	}
679 	else {
680 	    if (tp != pp && !hadnl) {
681 		(void)fputc('\n', cshout);
682 		hadnl = 1;
683 	    }
684 	    if (flag & NUMBER) {
685 		if (pp == tp)
686 		    (void)fprintf(cshout, "[%d]%s %c ", pp->p_index,
687 			    pp->p_index < 10 ? " " : "",
688 			    pp == pcurrent ? '+' :
689 			    (pp == pprevious ? '-' : ' '));
690 		else
691 		    (void)fprintf(cshout, "       ");
692 		hadnl = 0;
693 	    }
694 	    if (flag & FANCY) {
695 		(void)fprintf(cshout, "%5ld ", (long)pp->p_pid);
696 		hadnl = 0;
697 	    }
698 	    if (flag & (REASON | AREASON)) {
699 		if (flag & NAME)
700 		    format = "%-23s";
701 		else
702 		    format = "%s";
703 		if (pstatus == status) {
704 		    if (pp->p_reason == reason) {
705 			(void)fprintf(cshout, format, "");
706 			hadnl = 0;
707 			goto prcomd;
708 		    }
709 		    else
710 			reason = pp->p_reason;
711 		} else {
712 		    status = pstatus;
713 		    reason = pp->p_reason;
714 		}
715 		switch (status) {
716 		case PRUNNING:
717 		    (void)fprintf(cshout, format, "Running ");
718 		    hadnl = 0;
719 		    break;
720 		case PINTERRUPTED:
721 		case PSTOPPED:
722 		case PSIGNALED:
723                     /*
724                      * tell what happened to the background job
725                      * From: Michael Schroeder
726                      * <mlschroe@immd4.informatik.uni-erlangen.de>
727                      */
728                     if ((flag & REASON)
729                         || ((flag & AREASON)
730                             && reason != SIGINT
731                             && (reason != SIGPIPE
732                                 || (pp->p_flags & PPOU) == 0))) {
733 			(void)fprintf(cshout, format,
734 				       sys_siglist[(unsigned char)
735 						   pp->p_reason]);
736 			hadnl = 0;
737 		    }
738 		    break;
739 		case PNEXITED:
740 		case PAEXITED:
741 		    if (flag & REASON) {
742 			if (pp->p_reason)
743 			    (void)fprintf(cshout, "Exit %-18d", pp->p_reason);
744 			else
745 			    (void)fprintf(cshout, format, "Done");
746 			hadnl = 0;
747 		    }
748 		    break;
749 		default:
750 		    (void)fprintf(csherr, "BUG: status=%-9o", status);
751 		}
752 	    }
753 	}
754 prcomd:
755 	if (flag & NAME) {
756 	    (void)fprintf(cshout, "%s", vis_str(pp->p_command));
757 	    if (pp->p_flags & PPOU)
758 		(void)fprintf(cshout, " |");
759 	    if (pp->p_flags & PERR)
760 		(void)fputc('&', cshout);
761 	    hadnl = 0;
762 	}
763 	if (flag & (REASON | AREASON) && pp->p_flags & PDUMPED) {
764 	    (void)fprintf(cshout, " (core dumped)");
765 	    hadnl = 0;
766 	}
767 	if (tp == pp->p_friends) {
768 	    if (flag & AMPERSAND) {
769 		(void)fprintf(cshout, " &");
770 		hadnl = 0;
771 	    }
772 	    if (flag & JOBDIR &&
773 		!eq(tp->p_cwd->di_name, dcwd->di_name)) {
774 		(void)fprintf(cshout, " (wd: ");
775 		dtildepr(value(STRhome), tp->p_cwd->di_name);
776 		(void)fputc(')', cshout);
777 		hadnl = 0;
778 	    }
779 	}
780 	if (pp->p_flags & PPTIME && !(status & (PSTOPPED | PRUNNING))) {
781 	    if (!hadnl)
782 		(void)fprintf(cshout, "\n\t");
783 	    prusage(cshout, &zru, &pp->p_rusage, &pp->p_etime,
784 		    &pp->p_btime);
785 	    hadnl = 1;
786 	}
787 	if (tp == pp->p_friends) {
788 	    if (!hadnl) {
789 		(void)fputc('\n', cshout);
790 		hadnl = 1;
791 	    }
792 	    if (flag & SHELLDIR && !eq(tp->p_cwd->di_name, dcwd->di_name)) {
793 		(void)fprintf(cshout, "(wd now: ");
794 		dtildepr(value(STRhome), dcwd->di_name);
795 		(void)fprintf(cshout, ")\n");
796 		hadnl = 1;
797 	    }
798 	}
799     } while ((pp = pp->p_friends) != tp);
800     if (jobflags & PTIME && (jobflags & (PSTOPPED | PRUNNING)) == 0) {
801 	if (jobflags & NUMBER)
802 	    (void)fprintf(cshout, "       ");
803 	ptprint(tp);
804 	hadnl = 1;
805     }
806     (void)fflush(cshout);
807     return (jobflags);
808 }
809 
810 static void
ptprint(struct process * tp)811 ptprint(struct process *tp)
812 {
813     static struct rusage zru;
814     static struct timespec ztime;
815     struct rusage ru;
816     struct timespec tetime, diff;
817     struct process *pp;
818 
819     pp = tp;
820     ru = zru;
821     tetime = ztime;
822     do {
823 	ruadd(&ru, &pp->p_rusage);
824 	timespecsub(&pp->p_etime, &pp->p_btime, &diff);
825 	if (timespeccmp(&diff, &tetime, >))
826 	    tetime = diff;
827     } while ((pp = pp->p_friends) != tp);
828     prusage(cshout, &zru, &ru, &tetime, &ztime);
829 }
830 
831 /*
832  * dojobs - print all jobs
833  */
834 void
835 /*ARGSUSED*/
dojobs(Char ** v,struct command * t)836 dojobs(Char **v, struct command *t)
837 {
838     struct process *pp;
839     int flag, i;
840 
841     flag = NUMBER | NAME | REASON;
842     if (chkstop)
843 	chkstop = 2;
844     if (*++v) {
845 	if (v[1]) {
846 	    if (eq(*v, STRml)) {
847 		flag |= FANCY | JOBDIR;
848 	    } else if (eq(*v, STRmZ)) {
849 		if (v[1] && v[1][0]) {
850 		    setproctitle("%s", short2str(v[1]));
851 		} else {
852 		    setproctitle(NULL);
853 		}
854 		return;
855 	    } else {
856 		stderror(ERR_JOBS);
857 	    }
858 	}
859     }
860     for (i = 1; i <= pmaxindex; i++)
861 	for (pp = proclist.p_next; pp; pp = pp->p_next)
862 	    if (pp->p_index == i && pp->p_pid == pp->p_jobid) {
863 		pp->p_flags &= ~PNEEDNOTE;
864 		if (!(pprint(pp, flag) & (PRUNNING | PSTOPPED)))
865 		    pflush(pp);
866 		break;
867 	    }
868 }
869 
870 /*
871  * dofg - builtin - put the job into the foreground
872  */
873 void
874 /*ARGSUSED*/
dofg(Char ** v,struct command * t)875 dofg(Char **v, struct command *t)
876 {
877     struct process *pp;
878 
879     okpcntl();
880     ++v;
881     do {
882 	pp = pfind(*v);
883 	pstart(pp, 1);
884 	pjwait(pp);
885     } while (*v && *++v);
886 }
887 
888 /*
889  * %... - builtin - put the job into the foreground
890  */
891 void
892 /*ARGSUSED*/
dofg1(Char ** v,struct command * t)893 dofg1(Char **v, struct command *t)
894 {
895     struct process *pp;
896 
897     okpcntl();
898     pp = pfind(v[0]);
899     pstart(pp, 1);
900     pjwait(pp);
901 }
902 
903 /*
904  * dobg - builtin - put the job into the background
905  */
906 void
907 /*ARGSUSED*/
dobg(Char ** v,struct command * t)908 dobg(Char **v, struct command *t)
909 {
910     struct process *pp;
911 
912     okpcntl();
913     ++v;
914     do {
915 	pp = pfind(*v);
916 	pstart(pp, 0);
917     } while (*v && *++v);
918 }
919 
920 /*
921  * %... & - builtin - put the job into the background
922  */
923 void
924 /*ARGSUSED*/
dobg1(Char ** v,struct command * t)925 dobg1(Char **v, struct command *t)
926 {
927     struct process *pp;
928 
929     pp = pfind(v[0]);
930     pstart(pp, 0);
931 }
932 
933 /*
934  * dostop - builtin - stop the job
935  */
936 void
937 /*ARGSUSED*/
dostop(Char ** v,struct command * t)938 dostop(Char **v, struct command *t)
939 {
940     pkill(++v, SIGSTOP);
941 }
942 
943 /*
944  * dokill - builtin - superset of kill (1)
945  */
946 void
947 /*ARGSUSED*/
dokill(Char ** v,struct command * t)948 dokill(Char **v, struct command *t)
949 {
950     Char *signame;
951     char *name;
952     long signum;
953     char *ep;
954 
955     signum = SIGTERM;
956     v++;
957     if (v[0] && v[0][0] == '-') {
958 	if (v[0][1] == 'l') {
959 	    if (v[1]) {
960 		if (!Isdigit(v[1][0]))
961 		    stderror(ERR_NAME | ERR_BADSIG);
962 
963 		signum = strtol(short2str(v[1]), &ep, 10);
964 		if (signum < 0 || signum >= NSIG)
965 		    stderror(ERR_NAME | ERR_BADSIG);
966 		else if (signum == 0)
967 		    (void)fputc('0', cshout); /* 0's symbolic name is '0' */
968 		else
969 		    (void)fprintf(cshout, "%s ", sys_signame[signum]);
970 	    } else {
971 		for (signum = 1; signum < NSIG; signum++) {
972 		    (void)fprintf(cshout, "%s ", sys_signame[signum]);
973 		    if (signum == NSIG / 2)
974 			(void)fputc('\n', cshout);
975 	    	}
976 	    }
977 	    (void)fputc('\n', cshout);
978 	    return;
979 	}
980 	if (Isdigit(v[0][1])) {
981 	    signum = strtol(short2str(v[0] + 1), &ep, 10);
982 	    if (signum < 0 || signum >= NSIG || *ep)
983 		stderror(ERR_NAME | ERR_BADSIG);
984 	}
985 	else {
986 	    if (v[0][1] == 's' && v[0][2] == '\0')
987 		signame = *(++v);
988 	    else
989 		signame = &v[0][1];
990 
991 	    if (signame == NULL || v[1] == NULL)
992 		stderror(ERR_NAME | ERR_TOOFEW);
993 
994 	    name = short2str(signame);
995 	    for (signum = 1; signum < NSIG; signum++)
996 		if (!strcasecmp(sys_signame[signum], name) ||
997 		    (!strncasecmp("SIG", name, 3) &&	/* skip "SIG" prefix */
998 		     !strcasecmp(sys_signame[signum], name + 3)))
999 		    break;
1000 
1001 	    if (signum == NSIG) {
1002 		if (signame[0] == '0')
1003 		    signum = 0;
1004 		else {
1005 		    setname(vis_str(signame));
1006 		    stderror(ERR_NAME | ERR_UNKSIG);
1007 		}
1008 	    }
1009 	}
1010 	v++;
1011     }
1012     pkill(v, (int)signum);
1013 }
1014 
1015 static void
pkill(Char ** v,int signum)1016 pkill(Char **v, int signum)
1017 {
1018     struct process *pp, *np;
1019     Char *cp;
1020     sigset_t nsigset;
1021     int err1, jobflags, pid;
1022     char *ep;
1023 
1024     jobflags = 0;
1025     err1 = 0;
1026     sigemptyset(&nsigset);
1027     (void)sigaddset(&nsigset, SIGCHLD);
1028     if (setintr)
1029 	(void)sigaddset(&nsigset, SIGINT);
1030     (void)sigprocmask(SIG_BLOCK, &nsigset, NULL);
1031     gflag = 0, tglob(v);
1032     if (gflag) {
1033 	v = globall(v);
1034 	if (v == 0)
1035 	    stderror(ERR_NAME | ERR_NOMATCH);
1036     }
1037     else {
1038 	v = gargv = saveblk(v);
1039 	trim(v);
1040     }
1041 
1042     while (v && (cp = *v)) {
1043 	if (*cp == '%') {
1044 	    np = pp = pfind(cp);
1045 	    do
1046 		jobflags |= np->p_flags;
1047 	    while ((np = np->p_friends) != pp);
1048 	    switch (signum) {
1049 	    case SIGSTOP:
1050 	    case SIGTSTP:
1051 	    case SIGTTIN:
1052 	    case SIGTTOU:
1053 		if ((jobflags & PRUNNING) == 0) {
1054 		    (void)fprintf(csherr, "%s: Already suspended\n",
1055 				   vis_str(cp));
1056 		    err1++;
1057 		    goto cont;
1058 		}
1059 		break;
1060 		/*
1061 		 * suspend a process, kill -CONT %, then type jobs; the shell
1062 		 * says it is suspended, but it is running; thanks jaap..
1063 		 */
1064 	    case SIGCONT:
1065 		pstart(pp, 0);
1066 		goto cont;
1067 	    }
1068 	    if (kill(-pp->p_jobid, signum) < 0) {
1069 		(void)fprintf(csherr, "%s: %s\n", vis_str(cp),
1070 			       strerror(errno));
1071 		err1++;
1072 	    }
1073 	    if (signum == SIGTERM || signum == SIGHUP)
1074 		(void)kill(-pp->p_jobid, SIGCONT);
1075 	}
1076 	else if (!(Isdigit(*cp) || *cp == '-'))
1077 	    stderror(ERR_NAME | ERR_JOBARGS);
1078 	else {
1079 	    pid = (pid_t)strtoul(short2str(cp), &ep, 0);
1080 	    if (*ep) {
1081 		(void)fprintf(csherr, "%s: Badly formed number\n",
1082 		    short2str(cp));
1083 		err1++;
1084 		goto cont;
1085 	    } else if (kill(pid, signum) < 0) {
1086 		(void)fprintf(csherr, "%d: %s\n", pid, strerror(errno));
1087 		err1++;
1088 		goto cont;
1089 	    }
1090 	    if (signum == SIGTERM || signum == SIGHUP)
1091 		(void)kill((pid_t) pid, SIGCONT);
1092 	}
1093 cont:
1094 	v++;
1095     }
1096     if (gargv)
1097 	blkfree(gargv), gargv = 0;
1098     (void)sigprocmask(SIG_UNBLOCK, &nsigset, NULL);
1099     if (err1)
1100 	stderror(ERR_SILENT);
1101 }
1102 
1103 /*
1104  * pstart - start the job in foreground/background
1105  */
1106 void
pstart(struct process * pp,int foregnd)1107 pstart(struct process *pp, int foregnd)
1108 {
1109     struct process *np;
1110     sigset_t osigset, nsigset;
1111     long jobflags;
1112 
1113     jobflags = 0;
1114     sigemptyset(&nsigset);
1115     (void)sigaddset(&nsigset, SIGCHLD);
1116     (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
1117     np = pp;
1118     do {
1119 	jobflags |= np->p_flags;
1120 	if (np->p_flags & (PRUNNING | PSTOPPED)) {
1121 	    np->p_flags |= PRUNNING;
1122 	    np->p_flags &= ~PSTOPPED;
1123 	    if (foregnd)
1124 		np->p_flags |= PFOREGND;
1125 	    else
1126 		np->p_flags &= ~PFOREGND;
1127 	}
1128     } while ((np = np->p_friends) != pp);
1129     if (!foregnd)
1130 	pclrcurr(pp);
1131     (void)pprint(pp, foregnd ? NAME | JOBDIR : NUMBER | NAME | AMPERSAND);
1132     if (foregnd)
1133 	(void)tcsetpgrp(FSHTTY, pp->p_jobid);
1134     if (jobflags & PSTOPPED)
1135 	(void)kill(-pp->p_jobid, SIGCONT);
1136     (void)sigprocmask(SIG_SETMASK, &osigset, NULL);
1137 }
1138 
1139 void
panystop(int neednl)1140 panystop(int neednl)
1141 {
1142     struct process *pp;
1143 
1144     chkstop = 2;
1145     for (pp = proclist.p_next; pp; pp = pp->p_next)
1146 	if (pp->p_flags & PSTOPPED)
1147 	    stderror(ERR_STOPPED, neednl ? "\n" : "");
1148 }
1149 
1150 struct process *
pfind(Char * cp)1151 pfind(Char *cp)
1152 {
1153     struct process *pp, *np;
1154 
1155     if (cp == 0 || cp[1] == 0 || eq(cp, STRcent2) || eq(cp, STRcentplus)) {
1156 	if (pcurrent == NULL)
1157 	    stderror(ERR_NAME | ERR_JOBCUR);
1158 	return (pcurrent);
1159     }
1160     if (eq(cp, STRcentminus) || eq(cp, STRcenthash)) {
1161 	if (pprevious == NULL)
1162 	    stderror(ERR_NAME | ERR_JOBPREV);
1163 	return (pprevious);
1164     }
1165     if (Isdigit(cp[1])) {
1166 	int     idx = atoi(short2str(cp + 1));
1167 
1168 	for (pp = proclist.p_next; pp; pp = pp->p_next)
1169 	    if (pp->p_index == idx && pp->p_pid == pp->p_jobid)
1170 		return (pp);
1171 	stderror(ERR_NAME | ERR_NOSUCHJOB);
1172     }
1173     np = NULL;
1174     for (pp = proclist.p_next; pp; pp = pp->p_next)
1175 	if (pp->p_pid == pp->p_jobid) {
1176 	    if (cp[1] == '?') {
1177 		Char *dp;
1178 
1179 		for (dp = pp->p_command; *dp; dp++) {
1180 		    if (*dp != cp[2])
1181 			continue;
1182 		    if (prefix(cp + 2, dp))
1183 			goto match;
1184 		}
1185 	    }
1186 	    else if (prefix(cp + 1, pp->p_command)) {
1187 	match:
1188 		if (np)
1189 		    stderror(ERR_NAME | ERR_AMBIG);
1190 		np = pp;
1191 	    }
1192 	}
1193     if (np)
1194 	return (np);
1195     stderror(ERR_NAME | (cp[1] == '?' ? ERR_JOBPAT : ERR_NOSUCHJOB));
1196     /* NOTREACHED */
1197 }
1198 
1199 /*
1200  * pgetcurr - find most recent job that is not pp, preferably stopped
1201  */
1202 static struct process *
pgetcurr(struct process * pp)1203 pgetcurr(struct process *pp)
1204 {
1205     struct process *np, *xp;
1206 
1207     xp = NULL;
1208     for (np = proclist.p_next; np; np = np->p_next)
1209 	if (np != pcurrent && np != pp && np->p_pid &&
1210 	    np->p_pid == np->p_jobid) {
1211 	    if (np->p_flags & PSTOPPED)
1212 		return (np);
1213 	    if (xp == NULL)
1214 		xp = np;
1215 	}
1216     return (xp);
1217 }
1218 
1219 /*
1220  * donotify - flag the job so as to report termination asynchronously
1221  */
1222 void
1223 /*ARGSUSED*/
donotify(Char ** v,struct command * t)1224 donotify(Char **v, struct command *t)
1225 {
1226     struct process *pp;
1227 
1228     pp = pfind(*++v);
1229     pp->p_flags |= PNOTIFY;
1230 }
1231 
1232 /*
1233  * Do the fork and whatever should be done in the child side that
1234  * should not be done if we are not forking at all (like for simple builtin's)
1235  * Also do everything that needs any signals fiddled with in the parent side
1236  *
1237  * Wanttty tells whether process and/or tty pgrps are to be manipulated:
1238  *	-1:	leave tty alone; inherit pgrp from parent
1239  *	 0:	already have tty; manipulate process pgrps only
1240  *	 1:	want to claim tty; manipulate process and tty pgrps
1241  * It is usually just the value of tpgrp.
1242  */
1243 
1244 int
pfork(struct command * t,int wanttty)1245 pfork(struct command *t /* command we are forking for */, int wanttty)
1246 {
1247     int pgrp, pid;
1248     sigset_t osigset, nsigset;
1249     int ignint;
1250 
1251     ignint = 0;
1252     /*
1253      * A child will be uninterruptible only under very special conditions.
1254      * Remember that the semantics of '&' is implemented by disconnecting the
1255      * process from the tty so signals do not need to ignored just for '&'.
1256      * Thus signals are set to default action for children unless: we have had
1257      * an "onintr -" (then specifically ignored) we are not playing with
1258      * signals (inherit action)
1259      */
1260     if (setintr)
1261 	ignint = (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT))
1262 	    || (gointr && eq(gointr, STRminus));
1263     /*
1264      * Check for maximum nesting of 16 processes to avoid Forking loops
1265      */
1266     if (child == 16)
1267 	stderror(ERR_NESTING, 16);
1268     /*
1269      * Hold SIGCHLD until we have the process installed in our table.
1270      */
1271     sigemptyset(&nsigset);
1272     (void)sigaddset(&nsigset, SIGCHLD);
1273     (void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
1274     while ((pid = fork()) < 0)
1275 	if (setintr == 0)
1276 	    (void)sleep(FORKSLEEP);
1277 	else {
1278 	    (void)sigprocmask(SIG_SETMASK, &osigset, NULL);
1279 	    stderror(ERR_NOPROC);
1280 	}
1281     if (pid == 0) {
1282 	settimes();
1283 	pgrp = pcurrjob ? pcurrjob->p_jobid : getpid();
1284 	pflushall();
1285 	pcurrjob = NULL;
1286 	child++;
1287 	if (setintr) {
1288 	    setintr = 0;	/* until I think otherwise */
1289 	    /*
1290 	     * Children just get blown away on SIGINT, SIGQUIT unless "onintr
1291 	     * -" seen.
1292 	     */
1293 	    (void)signal(SIGINT, ignint ? SIG_IGN : SIG_DFL);
1294 	    (void)signal(SIGQUIT, ignint ? SIG_IGN : SIG_DFL);
1295 	    if (wanttty >= 0) {
1296 		/* make stoppable */
1297 		(void)signal(SIGTSTP, SIG_DFL);
1298 		(void)signal(SIGTTIN, SIG_DFL);
1299 		(void)signal(SIGTTOU, SIG_DFL);
1300 	    }
1301 	    (void)signal(SIGTERM, parterm);
1302 	}
1303 	else if (tpgrp == -1 && (t->t_dflg & F_NOINTERRUPT)) {
1304 	    (void)signal(SIGINT, SIG_IGN);
1305 	    (void)signal(SIGQUIT, SIG_IGN);
1306 	}
1307 	pgetty(wanttty, pgrp);
1308 	/*
1309 	 * Nohup and nice apply only to NODE_COMMAND's but it would be nice
1310 	 * (?!?) if you could say "nohup (foo;bar)" Then the parser would have
1311 	 * to know about nice/nohup/time
1312 	 */
1313 	if (t->t_dflg & F_NOHUP)
1314 	    (void)signal(SIGHUP, SIG_IGN);
1315 	if (t->t_dflg & F_NICE)
1316 	    (void)setpriority(PRIO_PROCESS, 0, t->t_nice);
1317     }
1318     else {
1319 	if (wanttty >= 0)
1320 	    (void)setpgid(pid, pcurrjob ? pcurrjob->p_jobid : pid);
1321 	palloc(pid, t);
1322 	(void)sigprocmask(SIG_SETMASK, &osigset, NULL);
1323     }
1324 
1325     return (pid);
1326 }
1327 
1328 static void
okpcntl(void)1329 okpcntl(void)
1330 {
1331     if (tpgrp == -1)
1332 	stderror(ERR_JOBCONTROL);
1333     if (tpgrp == 0)
1334 	stderror(ERR_JOBCTRLSUB);
1335     /* NOTREACHED */
1336 }
1337 
1338 /*
1339  * if we don't have vfork(), things can still go in the wrong order
1340  * resulting in the famous 'Stopped (tty output)'. But some systems
1341  * don't permit the setpgid() call, (these are more recent secure
1342  * systems such as ibm's aix). Then we'd rather print an error message
1343  * than hang the shell!
1344  * I am open to suggestions how to fix that.
1345  */
1346 void
pgetty(int wanttty,int pgrp)1347 pgetty(int wanttty, int pgrp)
1348 {
1349     sigset_t osigset, nsigset;
1350 
1351     /*
1352      * christos: I am blocking the tty signals till I've set things
1353      * correctly....
1354      */
1355     if (wanttty > 0) {
1356 	sigemptyset(&nsigset);
1357 	(void)sigaddset(&nsigset, SIGTSTP);
1358 	(void)sigaddset(&nsigset, SIGTTIN);
1359 	(void)sigaddset(&nsigset, SIGTTOU);
1360 	(void)sigprocmask(SIG_BLOCK, &nsigset, &osigset);
1361     }
1362     /*
1363      * From: Michael Schroeder <mlschroe@immd4.informatik.uni-erlangen.de>
1364      * Don't check for tpgrp >= 0 so even non-interactive shells give
1365      * background jobs process groups Same for the comparison in the other part
1366      * of the #ifdef
1367      */
1368     if (wanttty >= 0)
1369 	if (setpgid(0, pgrp) == -1) {
1370 	    (void)fprintf(csherr, "csh: setpgid error.\n");
1371 	    xexit(0);
1372 	}
1373 
1374     if (wanttty > 0) {
1375 	(void)tcsetpgrp(FSHTTY, pgrp);
1376 	(void)sigprocmask(SIG_SETMASK, &osigset, NULL);
1377     }
1378 
1379     if (tpgrp > 0)
1380 	tpgrp = 0;		/* gave tty away */
1381 }
1382