xref: /freebsd/bin/sh/trap.c (revision a043cc4c68b0e8b0ed716275ac3df27621d1b3f0)
14b88c807SRodney W. Grimes /*-
24b88c807SRodney W. Grimes  * Copyright (c) 1991, 1993
34b88c807SRodney W. Grimes  *	The Regents of the University of California.  All rights reserved.
44b88c807SRodney W. Grimes  *
54b88c807SRodney W. Grimes  * This code is derived from software contributed to Berkeley by
64b88c807SRodney W. Grimes  * Kenneth Almquist.
74b88c807SRodney W. Grimes  *
84b88c807SRodney W. Grimes  * Redistribution and use in source and binary forms, with or without
94b88c807SRodney W. Grimes  * modification, are permitted provided that the following conditions
104b88c807SRodney W. Grimes  * are met:
114b88c807SRodney W. Grimes  * 1. Redistributions of source code must retain the above copyright
124b88c807SRodney W. Grimes  *    notice, this list of conditions and the following disclaimer.
134b88c807SRodney W. Grimes  * 2. Redistributions in binary form must reproduce the above copyright
144b88c807SRodney W. Grimes  *    notice, this list of conditions and the following disclaimer in the
154b88c807SRodney W. Grimes  *    documentation and/or other materials provided with the distribution.
164b88c807SRodney W. Grimes  * 4. Neither the name of the University nor the names of its contributors
174b88c807SRodney W. Grimes  *    may be used to endorse or promote products derived from this software
184b88c807SRodney W. Grimes  *    without specific prior written permission.
194b88c807SRodney W. Grimes  *
204b88c807SRodney W. Grimes  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
214b88c807SRodney W. Grimes  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
224b88c807SRodney W. Grimes  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
234b88c807SRodney W. Grimes  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
244b88c807SRodney W. Grimes  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
254b88c807SRodney W. Grimes  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
264b88c807SRodney W. Grimes  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
274b88c807SRodney W. Grimes  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
284b88c807SRodney W. Grimes  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
294b88c807SRodney W. Grimes  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
304b88c807SRodney W. Grimes  * SUCH DAMAGE.
314b88c807SRodney W. Grimes  */
324b88c807SRodney W. Grimes 
334b88c807SRodney W. Grimes #ifndef lint
343d7b5b93SPhilippe Charnier #if 0
353d7b5b93SPhilippe Charnier static char sccsid[] = "@(#)trap.c	8.5 (Berkeley) 6/5/95";
363d7b5b93SPhilippe Charnier #endif
374b88c807SRodney W. Grimes #endif /* not lint */
382749b141SDavid E. O'Brien #include <sys/cdefs.h>
392749b141SDavid E. O'Brien __FBSDID("$FreeBSD$");
404b88c807SRodney W. Grimes 
41aa9caaf6SPeter Wemm #include <signal.h>
42aa9caaf6SPeter Wemm #include <unistd.h>
43aa9caaf6SPeter Wemm #include <stdlib.h>
44aa9caaf6SPeter Wemm 
454b88c807SRodney W. Grimes #include "shell.h"
464b88c807SRodney W. Grimes #include "main.h"
474b88c807SRodney W. Grimes #include "nodes.h"	/* for other headers */
484b88c807SRodney W. Grimes #include "eval.h"
494b88c807SRodney W. Grimes #include "jobs.h"
50aa9caaf6SPeter Wemm #include "show.h"
514b88c807SRodney W. Grimes #include "options.h"
524b88c807SRodney W. Grimes #include "syntax.h"
534b88c807SRodney W. Grimes #include "output.h"
544b88c807SRodney W. Grimes #include "memalloc.h"
554b88c807SRodney W. Grimes #include "error.h"
564b88c807SRodney W. Grimes #include "trap.h"
574b88c807SRodney W. Grimes #include "mystring.h"
589de7305eSTim J. Robbins #include "myhistedit.h"
594b88c807SRodney W. Grimes 
604b88c807SRodney W. Grimes 
614b88c807SRodney W. Grimes /*
624b88c807SRodney W. Grimes  * Sigmode records the current value of the signal handlers for the various
634b88c807SRodney W. Grimes  * modes.  A value of zero means that the current handler is not known.
644b88c807SRodney W. Grimes  * S_HARD_IGN indicates that the signal was ignored on entry to the shell,
654b88c807SRodney W. Grimes  */
664b88c807SRodney W. Grimes 
674b88c807SRodney W. Grimes #define S_DFL 1			/* default signal handling (SIG_DFL) */
684b88c807SRodney W. Grimes #define S_CATCH 2		/* signal is caught */
694b88c807SRodney W. Grimes #define S_IGN 3			/* signal is ignored (SIG_IGN) */
7046be34b9SKris Kennaway #define S_HARD_IGN 4		/* signal is ignored permanently */
714b88c807SRodney W. Grimes #define S_RESET 5		/* temporary - to reset a hard ignored sig */
724b88c807SRodney W. Grimes 
734b88c807SRodney W. Grimes 
74aa9caaf6SPeter Wemm MKINIT char sigmode[NSIG];	/* current value of signal */
754b88c807SRodney W. Grimes int pendingsigs;		/* indicates some signal received */
761f40b47bSMartin Cracauer int in_dotrap;			/* do we execute in a trap handler? */
77135421ddSMartin Cracauer static char *volatile trap[NSIG];	/* trap handler commands */
787a8e920bSMartin Cracauer static volatile sig_atomic_t gotsig[NSIG];
797a8e920bSMartin Cracauer 				/* indicates specified signal received */
80f98e1b80SSteve Price static int ignore_sigchld;	/* Used while handling SIGCHLD traps. */
81be58cc48STim J. Robbins volatile sig_atomic_t gotwinch;
824b88c807SRodney W. Grimes 
8370df11eaSJilles Tjoelker static int exiting;		/* exitshell() has been called */
8470df11eaSJilles Tjoelker static int exiting_exitstatus;	/* value passed to exitshell() */
8570df11eaSJilles Tjoelker 
8688328642SDavid E. O'Brien static int getsigaction(int, sig_t *);
87aa9caaf6SPeter Wemm 
88f98e1b80SSteve Price 
89f98e1b80SSteve Price /*
90f98e1b80SSteve Price  * Map a string to a signal number.
9197054a76SNate Lawson  *
9297054a76SNate Lawson  * Note: the signal number may exceed NSIG.
93f98e1b80SSteve Price  */
9488328642SDavid E. O'Brien static int
955134c3f7SWarner Losh sigstring_to_signum(char *sig)
96f98e1b80SSteve Price {
97f98e1b80SSteve Price 
98f98e1b80SSteve Price 	if (is_number(sig)) {
99f98e1b80SSteve Price 		int signo;
100f98e1b80SSteve Price 
101f98e1b80SSteve Price 		signo = atoi(sig);
102f98e1b80SSteve Price 		return ((signo >= 0 && signo < NSIG) ? signo : (-1));
103f98e1b80SSteve Price 	} else if (strcasecmp(sig, "exit") == 0) {
104f98e1b80SSteve Price 		return (0);
105f98e1b80SSteve Price 	} else {
106f98e1b80SSteve Price 		int n;
107f98e1b80SSteve Price 
108f98e1b80SSteve Price 		if (strncasecmp(sig, "sig", 3) == 0)
109f98e1b80SSteve Price 			sig += 3;
1101b13752aSNate Lawson 		for (n = 1; n < sys_nsig; n++)
111aa0b7126SNate Lawson 			if (sys_signame[n] &&
112aa0b7126SNate Lawson 			    strcasecmp(sys_signame[n], sig) == 0)
113f98e1b80SSteve Price 				return (n);
114f98e1b80SSteve Price 	}
115f98e1b80SSteve Price 	return (-1);
116f98e1b80SSteve Price }
117f98e1b80SSteve Price 
118f98e1b80SSteve Price 
119f98e1b80SSteve Price /*
120f98e1b80SSteve Price  * Print a list of valid signal names.
121f98e1b80SSteve Price  */
12288328642SDavid E. O'Brien static void
1235134c3f7SWarner Losh printsignals(void)
124f98e1b80SSteve Price {
12597054a76SNate Lawson 	int n, outlen;
126f98e1b80SSteve Price 
12797054a76SNate Lawson 	outlen = 0;
1281b13752aSNate Lawson 	for (n = 1; n < sys_nsig; n++) {
12997054a76SNate Lawson 		if (sys_signame[n]) {
130f98e1b80SSteve Price 			out1fmt("%s", sys_signame[n]);
13197054a76SNate Lawson 			outlen += strlen(sys_signame[n]);
13297054a76SNate Lawson 		} else {
13397054a76SNate Lawson 			out1fmt("%d", n);
13497054a76SNate Lawson 			outlen += 3;	/* good enough */
13597054a76SNate Lawson 		}
13697054a76SNate Lawson 		++outlen;
13745b3c176SJilles Tjoelker 		if (outlen > 71 || n == sys_nsig - 1) {
138f98e1b80SSteve Price 			out1str("\n");
13997054a76SNate Lawson 			outlen = 0;
14097054a76SNate Lawson 		} else {
141f98e1b80SSteve Price 			out1c(' ');
142f98e1b80SSteve Price 		}
143f98e1b80SSteve Price 	}
14497054a76SNate Lawson }
145f98e1b80SSteve Price 
146f98e1b80SSteve Price 
1474b88c807SRodney W. Grimes /*
1484b88c807SRodney W. Grimes  * The trap builtin.
1494b88c807SRodney W. Grimes  */
150aa9caaf6SPeter Wemm int
1515134c3f7SWarner Losh trapcmd(int argc, char **argv)
152aa9caaf6SPeter Wemm {
1534b88c807SRodney W. Grimes 	char *action;
1544b88c807SRodney W. Grimes 	int signo;
155e3c2cd72SJilles Tjoelker 	int errors = 0;
156*a043cc4cSJilles Tjoelker 	int i;
1574b88c807SRodney W. Grimes 
158*a043cc4cSJilles Tjoelker 	while ((i = nextopt("l")) != '\0') {
159*a043cc4cSJilles Tjoelker 		switch (i) {
160*a043cc4cSJilles Tjoelker 		case 'l':
161*a043cc4cSJilles Tjoelker 			printsignals();
162*a043cc4cSJilles Tjoelker 			return (0);
163*a043cc4cSJilles Tjoelker 		}
164*a043cc4cSJilles Tjoelker 	}
165*a043cc4cSJilles Tjoelker 	argv = argptr;
166*a043cc4cSJilles Tjoelker 
167*a043cc4cSJilles Tjoelker 	if (*argv == NULL) {
1681b13752aSNate Lawson 		for (signo = 0 ; signo < sys_nsig ; signo++) {
16997054a76SNate Lawson 			if (signo < NSIG && trap[signo] != NULL) {
1702a5e306dSStefan Farfeleder 				out1str("trap -- ");
1712a5e306dSStefan Farfeleder 				out1qstr(trap[signo]);
17297054a76SNate Lawson 				if (signo == 0) {
1732a5e306dSStefan Farfeleder 					out1str(" exit\n");
17497054a76SNate Lawson 				} else if (sys_signame[signo]) {
1752a5e306dSStefan Farfeleder 					out1fmt(" %s\n", sys_signame[signo]);
17697054a76SNate Lawson 				} else {
1772a5e306dSStefan Farfeleder 					out1fmt(" %d\n", signo);
17897054a76SNate Lawson 				}
17997054a76SNate Lawson 			}
1804b88c807SRodney W. Grimes 		}
1814b88c807SRodney W. Grimes 		return 0;
1824b88c807SRodney W. Grimes 	}
1834b88c807SRodney W. Grimes 	action = NULL;
184f98e1b80SSteve Price 	if (*argv && sigstring_to_signum(*argv) == -1) {
185*a043cc4cSJilles Tjoelker 		if (strcmp(*argv, "-") == 0)
186*a043cc4cSJilles Tjoelker 			argv++;
187*a043cc4cSJilles Tjoelker 		else {
188f98e1b80SSteve Price 			action = *argv;
189f98e1b80SSteve Price 			argv++;
190f98e1b80SSteve Price 		}
191f98e1b80SSteve Price 	}
192f98e1b80SSteve Price 	while (*argv) {
193e3c2cd72SJilles Tjoelker 		if ((signo = sigstring_to_signum(*argv)) == -1) {
1945fe9123fSJilles Tjoelker 			warning("bad signal %s", *argv);
195e3c2cd72SJilles Tjoelker 			errors = 1;
196e3c2cd72SJilles Tjoelker 		}
1974b88c807SRodney W. Grimes 		INTOFF;
1984b88c807SRodney W. Grimes 		if (action)
1994b88c807SRodney W. Grimes 			action = savestr(action);
2004b88c807SRodney W. Grimes 		if (trap[signo])
2014b88c807SRodney W. Grimes 			ckfree(trap[signo]);
2024b88c807SRodney W. Grimes 		trap[signo] = action;
2034b88c807SRodney W. Grimes 		if (signo != 0)
2044b88c807SRodney W. Grimes 			setsignal(signo);
2054b88c807SRodney W. Grimes 		INTON;
206f98e1b80SSteve Price 		argv++;
2074b88c807SRodney W. Grimes 	}
208e3c2cd72SJilles Tjoelker 	return errors;
2094b88c807SRodney W. Grimes }
2104b88c807SRodney W. Grimes 
2114b88c807SRodney W. Grimes 
2124b88c807SRodney W. Grimes /*
2134b88c807SRodney W. Grimes  * Clear traps on a fork.
2144b88c807SRodney W. Grimes  */
2154b88c807SRodney W. Grimes void
2165134c3f7SWarner Losh clear_traps(void)
217f98e1b80SSteve Price {
218135421ddSMartin Cracauer 	char *volatile *tp;
2194b88c807SRodney W. Grimes 
220f98e1b80SSteve Price 	for (tp = trap ; tp <= &trap[NSIG - 1] ; tp++) {
2214b88c807SRodney W. Grimes 		if (*tp && **tp) {	/* trap not NULL or SIG_IGN */
2224b88c807SRodney W. Grimes 			INTOFF;
2234b88c807SRodney W. Grimes 			ckfree(*tp);
2244b88c807SRodney W. Grimes 			*tp = NULL;
2254b88c807SRodney W. Grimes 			if (tp != &trap[0])
2264b88c807SRodney W. Grimes 				setsignal(tp - trap);
2274b88c807SRodney W. Grimes 			INTON;
2284b88c807SRodney W. Grimes 		}
2294b88c807SRodney W. Grimes 	}
2304b88c807SRodney W. Grimes }
2314b88c807SRodney W. Grimes 
2324b88c807SRodney W. Grimes 
2334b88c807SRodney W. Grimes /*
2346e28dacfSJilles Tjoelker  * Check if we have any traps enabled.
2356e28dacfSJilles Tjoelker  */
2366e28dacfSJilles Tjoelker int
2376e28dacfSJilles Tjoelker have_traps(void)
2386e28dacfSJilles Tjoelker {
2396e28dacfSJilles Tjoelker 	char *volatile *tp;
2406e28dacfSJilles Tjoelker 
2416e28dacfSJilles Tjoelker 	for (tp = trap ; tp <= &trap[NSIG - 1] ; tp++) {
2426e28dacfSJilles Tjoelker 		if (*tp && **tp)	/* trap not NULL or SIG_IGN */
2436e28dacfSJilles Tjoelker 			return 1;
2446e28dacfSJilles Tjoelker 	}
2456e28dacfSJilles Tjoelker 	return 0;
2466e28dacfSJilles Tjoelker }
2476e28dacfSJilles Tjoelker 
2486e28dacfSJilles Tjoelker /*
2494b88c807SRodney W. Grimes  * Set the signal handler for the specified signal.  The routine figures
2504b88c807SRodney W. Grimes  * out what it should be set to.
2514b88c807SRodney W. Grimes  */
25228701136SBruce Evans void
2535134c3f7SWarner Losh setsignal(int signo)
254aa9caaf6SPeter Wemm {
2554b88c807SRodney W. Grimes 	int action;
2563f228d74SJilles Tjoelker 	sig_t sigact = SIG_DFL;
2573f228d74SJilles Tjoelker 	struct sigaction sa;
2584b88c807SRodney W. Grimes 	char *t;
2594b88c807SRodney W. Grimes 
2604b88c807SRodney W. Grimes 	if ((t = trap[signo]) == NULL)
2614b88c807SRodney W. Grimes 		action = S_DFL;
2624b88c807SRodney W. Grimes 	else if (*t != '\0')
2634b88c807SRodney W. Grimes 		action = S_CATCH;
2644b88c807SRodney W. Grimes 	else
2654b88c807SRodney W. Grimes 		action = S_IGN;
2667a8e920bSMartin Cracauer 	if (action == S_DFL) {
2674b88c807SRodney W. Grimes 		switch (signo) {
2684b88c807SRodney W. Grimes 		case SIGINT:
2694b88c807SRodney W. Grimes 			action = S_CATCH;
2704b88c807SRodney W. Grimes 			break;
2714b88c807SRodney W. Grimes 		case SIGQUIT:
2724b88c807SRodney W. Grimes #ifdef DEBUG
2734b88c807SRodney W. Grimes 			{
2744b88c807SRodney W. Grimes 			extern int debug;
2754b88c807SRodney W. Grimes 
2764b88c807SRodney W. Grimes 			if (debug)
2774b88c807SRodney W. Grimes 				break;
2784b88c807SRodney W. Grimes 			}
2794b88c807SRodney W. Grimes #endif
28040d009a7SMartin Cracauer 			action = S_CATCH;
2817a8e920bSMartin Cracauer 			break;
2824b88c807SRodney W. Grimes 		case SIGTERM:
2837a8e920bSMartin Cracauer 			if (rootshell && iflag)
2844b88c807SRodney W. Grimes 				action = S_IGN;
2854b88c807SRodney W. Grimes 			break;
2864b88c807SRodney W. Grimes #if JOBS
2874b88c807SRodney W. Grimes 		case SIGTSTP:
2884b88c807SRodney W. Grimes 		case SIGTTOU:
2897a8e920bSMartin Cracauer 			if (rootshell && mflag)
2904b88c807SRodney W. Grimes 				action = S_IGN;
2914b88c807SRodney W. Grimes 			break;
2924b88c807SRodney W. Grimes #endif
2939de7305eSTim J. Robbins #ifndef NO_HISTORY
2949de7305eSTim J. Robbins 		case SIGWINCH:
295be58cc48STim J. Robbins 			if (rootshell && iflag)
2969de7305eSTim J. Robbins 				action = S_CATCH;
2979de7305eSTim J. Robbins 			break;
2989de7305eSTim J. Robbins #endif
2994b88c807SRodney W. Grimes 		}
3004b88c807SRodney W. Grimes 	}
301aa9caaf6SPeter Wemm 
302f98e1b80SSteve Price 	t = &sigmode[signo];
3034b88c807SRodney W. Grimes 	if (*t == 0) {
3044b88c807SRodney W. Grimes 		/*
3054b88c807SRodney W. Grimes 		 * current setting unknown
3064b88c807SRodney W. Grimes 		 */
307aa9caaf6SPeter Wemm 		if (!getsigaction(signo, &sigact)) {
308aa9caaf6SPeter Wemm 			/*
309aa9caaf6SPeter Wemm 			 * Pretend it worked; maybe we should give a warning
310aa9caaf6SPeter Wemm 			 * here, but other shells don't. We don't alter
311aa9caaf6SPeter Wemm 			 * sigmode, so that we retry every time.
312aa9caaf6SPeter Wemm 			 */
31328701136SBruce Evans 			return;
314aa9caaf6SPeter Wemm 		}
3154b88c807SRodney W. Grimes 		if (sigact == SIG_IGN) {
3164b88c807SRodney W. Grimes 			if (mflag && (signo == SIGTSTP ||
3174b88c807SRodney W. Grimes 			     signo == SIGTTIN || signo == SIGTTOU)) {
3184b88c807SRodney W. Grimes 				*t = S_IGN;	/* don't hard ignore these */
3194b88c807SRodney W. Grimes 			} else
3204b88c807SRodney W. Grimes 				*t = S_HARD_IGN;
3214b88c807SRodney W. Grimes 		} else {
3224b88c807SRodney W. Grimes 			*t = S_RESET;	/* force to be set */
3234b88c807SRodney W. Grimes 		}
3244b88c807SRodney W. Grimes 	}
3254b88c807SRodney W. Grimes 	if (*t == S_HARD_IGN || *t == action)
32628701136SBruce Evans 		return;
3274b88c807SRodney W. Grimes 	switch (action) {
3284b88c807SRodney W. Grimes 		case S_DFL:	sigact = SIG_DFL;	break;
3294b88c807SRodney W. Grimes 		case S_CATCH:  	sigact = onsig;		break;
3304b88c807SRodney W. Grimes 		case S_IGN:	sigact = SIG_IGN;	break;
3314b88c807SRodney W. Grimes 	}
3324b88c807SRodney W. Grimes 	*t = action;
3333f228d74SJilles Tjoelker 	sa.sa_handler = sigact;
3343f228d74SJilles Tjoelker 	sa.sa_flags = 0;
3353f228d74SJilles Tjoelker 	sigemptyset(&sa.sa_mask);
3363f228d74SJilles Tjoelker 	sigaction(signo, &sa, NULL);
3374b88c807SRodney W. Grimes }
3384b88c807SRodney W. Grimes 
339f98e1b80SSteve Price 
3404b88c807SRodney W. Grimes /*
3414b88c807SRodney W. Grimes  * Return the current setting for sig w/o changing it.
3424b88c807SRodney W. Grimes  */
34388328642SDavid E. O'Brien static int
3445134c3f7SWarner Losh getsigaction(int signo, sig_t *sigact)
345aa9caaf6SPeter Wemm {
3464b88c807SRodney W. Grimes 	struct sigaction sa;
3474b88c807SRodney W. Grimes 
3484b88c807SRodney W. Grimes 	if (sigaction(signo, (struct sigaction *)0, &sa) == -1)
349aa9caaf6SPeter Wemm 		return 0;
350aa9caaf6SPeter Wemm 	*sigact = (sig_t) sa.sa_handler;
351aa9caaf6SPeter Wemm 	return 1;
3524b88c807SRodney W. Grimes }
3534b88c807SRodney W. Grimes 
354f98e1b80SSteve Price 
3554b88c807SRodney W. Grimes /*
3564b88c807SRodney W. Grimes  * Ignore a signal.
3574b88c807SRodney W. Grimes  */
3584b88c807SRodney W. Grimes void
3595134c3f7SWarner Losh ignoresig(int signo)
360aa9caaf6SPeter Wemm {
361f98e1b80SSteve Price 
362f98e1b80SSteve Price 	if (sigmode[signo] != S_IGN && sigmode[signo] != S_HARD_IGN) {
3634b88c807SRodney W. Grimes 		signal(signo, SIG_IGN);
3644b88c807SRodney W. Grimes 	}
365f98e1b80SSteve Price 	sigmode[signo] = S_HARD_IGN;
3664b88c807SRodney W. Grimes }
3674b88c807SRodney W. Grimes 
3684b88c807SRodney W. Grimes 
3694b88c807SRodney W. Grimes #ifdef mkinit
370aa9caaf6SPeter Wemm INCLUDE <signal.h>
3714b88c807SRodney W. Grimes INCLUDE "trap.h"
3724b88c807SRodney W. Grimes 
3734b88c807SRodney W. Grimes SHELLPROC {
3744b88c807SRodney W. Grimes 	char *sm;
3754b88c807SRodney W. Grimes 
3764b88c807SRodney W. Grimes 	clear_traps();
377aa9caaf6SPeter Wemm 	for (sm = sigmode ; sm < sigmode + NSIG ; sm++) {
3784b88c807SRodney W. Grimes 		if (*sm == S_IGN)
3794b88c807SRodney W. Grimes 			*sm = S_HARD_IGN;
3804b88c807SRodney W. Grimes 	}
3814b88c807SRodney W. Grimes }
3824b88c807SRodney W. Grimes #endif
3834b88c807SRodney W. Grimes 
3844b88c807SRodney W. Grimes 
3854b88c807SRodney W. Grimes /*
3864b88c807SRodney W. Grimes  * Signal handler.
3874b88c807SRodney W. Grimes  */
3884b88c807SRodney W. Grimes void
3895134c3f7SWarner Losh onsig(int signo)
390aa9caaf6SPeter Wemm {
39128701136SBruce Evans 
3924b88c807SRodney W. Grimes 	if (signo == SIGINT && trap[SIGINT] == NULL) {
3934b88c807SRodney W. Grimes 		onint();
3944b88c807SRodney W. Grimes 		return;
3954b88c807SRodney W. Grimes 	}
396135421ddSMartin Cracauer 
397f98e1b80SSteve Price 	if (signo != SIGCHLD || !ignore_sigchld)
398f98e1b80SSteve Price 		gotsig[signo] = 1;
3994b88c807SRodney W. Grimes 	pendingsigs++;
400135421ddSMartin Cracauer 
401135421ddSMartin Cracauer 	/* If we are currently in a wait builtin, prepare to break it */
402135421ddSMartin Cracauer 	if ((signo == SIGINT || signo == SIGQUIT) && in_waitcmd != 0)
4037a8e920bSMartin Cracauer 		breakwaitcmd = 1;
404135421ddSMartin Cracauer 	/*
4059bbfa415SMartin Cracauer 	 * If a trap is set, not ignored and not the null command, we need
4069bbfa415SMartin Cracauer 	 * to make sure traps are executed even when a child blocks signals.
407135421ddSMartin Cracauer 	 */
408c1c72a3cSMartin Cracauer 	if (Tflag &&
409c1c72a3cSMartin Cracauer 	    trap[signo] != NULL &&
410f7d95a07SRalf S. Engelschall 	    ! (trap[signo][0] == '\0') &&
411e6ac45ddSMartin Cracauer 	    ! (trap[signo][0] == ':' && trap[signo][1] == '\0'))
412135421ddSMartin Cracauer 		breakwaitcmd = 1;
4139de7305eSTim J. Robbins 
4149de7305eSTim J. Robbins #ifndef NO_HISTORY
4159de7305eSTim J. Robbins 	if (signo == SIGWINCH)
416be58cc48STim J. Robbins 		gotwinch = 1;
4179de7305eSTim J. Robbins #endif
4184b88c807SRodney W. Grimes }
4194b88c807SRodney W. Grimes 
4204b88c807SRodney W. Grimes 
4214b88c807SRodney W. Grimes /*
4224b88c807SRodney W. Grimes  * Called to execute a trap.  Perhaps we should avoid entering new trap
4234b88c807SRodney W. Grimes  * handlers while we are executing a trap handler.
4244b88c807SRodney W. Grimes  */
4254b88c807SRodney W. Grimes void
4265134c3f7SWarner Losh dotrap(void)
427f98e1b80SSteve Price {
4284b88c807SRodney W. Grimes 	int i;
4294b88c807SRodney W. Grimes 	int savestatus;
4304b88c807SRodney W. Grimes 
4317a8e920bSMartin Cracauer 	in_dotrap++;
4324b88c807SRodney W. Grimes 	for (;;) {
433f98e1b80SSteve Price 		for (i = 1; i < NSIG; i++) {
434f98e1b80SSteve Price 			if (gotsig[i]) {
435f98e1b80SSteve Price 				gotsig[i] = 0;
436f98e1b80SSteve Price 				if (trap[i]) {
437f98e1b80SSteve Price 					/*
438aa0b7126SNate Lawson 					 * Ignore SIGCHLD to avoid infinite
439aa0b7126SNate Lawson 					 * recursion if the trap action does
440aa0b7126SNate Lawson 					 * a fork.
441f98e1b80SSteve Price 					 */
442f98e1b80SSteve Price 					if (i == SIGCHLD)
443f98e1b80SSteve Price 						ignore_sigchld++;
4444b88c807SRodney W. Grimes 					savestatus = exitstatus;
445cb806389SStefan Farfeleder 					evalstring(trap[i], 0);
4464b88c807SRodney W. Grimes 					exitstatus = savestatus;
447f98e1b80SSteve Price 					if (i == SIGCHLD)
448f98e1b80SSteve Price 						ignore_sigchld--;
4494b88c807SRodney W. Grimes 				}
450f98e1b80SSteve Price 				break;
451f98e1b80SSteve Price 			}
452f98e1b80SSteve Price 		}
453f98e1b80SSteve Price 		if (i >= NSIG)
454f98e1b80SSteve Price 			break;
455f98e1b80SSteve Price 	}
4567a8e920bSMartin Cracauer 	in_dotrap--;
4574b88c807SRodney W. Grimes 	pendingsigs = 0;
4584b88c807SRodney W. Grimes }
4594b88c807SRodney W. Grimes 
4604b88c807SRodney W. Grimes 
4614b88c807SRodney W. Grimes /*
4624b88c807SRodney W. Grimes  * Controls whether the shell is interactive or not.
4634b88c807SRodney W. Grimes  */
4644b88c807SRodney W. Grimes void
4655134c3f7SWarner Losh setinteractive(int on)
466aa9caaf6SPeter Wemm {
4677a8e920bSMartin Cracauer 	static int is_interactive = -1;
4684b88c807SRodney W. Grimes 
4694b88c807SRodney W. Grimes 	if (on == is_interactive)
4704b88c807SRodney W. Grimes 		return;
4714b88c807SRodney W. Grimes 	setsignal(SIGINT);
4724b88c807SRodney W. Grimes 	setsignal(SIGQUIT);
4734b88c807SRodney W. Grimes 	setsignal(SIGTERM);
4749de7305eSTim J. Robbins #ifndef NO_HISTORY
4759de7305eSTim J. Robbins 	setsignal(SIGWINCH);
4769de7305eSTim J. Robbins #endif
4774b88c807SRodney W. Grimes 	is_interactive = on;
4784b88c807SRodney W. Grimes }
4794b88c807SRodney W. Grimes 
4804b88c807SRodney W. Grimes 
4814b88c807SRodney W. Grimes /*
4824b88c807SRodney W. Grimes  * Called to exit the shell.
4834b88c807SRodney W. Grimes  */
4844b88c807SRodney W. Grimes void
4855134c3f7SWarner Losh exitshell(int status)
486aa9caaf6SPeter Wemm {
48770df11eaSJilles Tjoelker 	TRACE(("exitshell(%d) pid=%d\n", status, getpid()));
48870df11eaSJilles Tjoelker 	exiting = 1;
48970df11eaSJilles Tjoelker 	exiting_exitstatus = status;
49070df11eaSJilles Tjoelker 	exitshell_savedstatus();
49170df11eaSJilles Tjoelker }
49270df11eaSJilles Tjoelker 
49370df11eaSJilles Tjoelker void
49470df11eaSJilles Tjoelker exitshell_savedstatus(void)
49570df11eaSJilles Tjoelker {
4964b88c807SRodney W. Grimes 	struct jmploc loc1, loc2;
4974b88c807SRodney W. Grimes 	char *p;
4984b88c807SRodney W. Grimes 
49970df11eaSJilles Tjoelker 	if (!exiting)
50070df11eaSJilles Tjoelker 		exiting_exitstatus = oexitstatus;
50170df11eaSJilles Tjoelker 	exitstatus = oexitstatus = exiting_exitstatus;
5024b88c807SRodney W. Grimes 	if (setjmp(loc1.loc)) {
5034b88c807SRodney W. Grimes 		goto l1;
5044b88c807SRodney W. Grimes 	}
5054b88c807SRodney W. Grimes 	if (setjmp(loc2.loc)) {
5064b88c807SRodney W. Grimes 		goto l2;
5074b88c807SRodney W. Grimes 	}
5084b88c807SRodney W. Grimes 	handler = &loc1;
5094b88c807SRodney W. Grimes 	if ((p = trap[0]) != NULL && *p != '\0') {
5104b88c807SRodney W. Grimes 		trap[0] = NULL;
511cb806389SStefan Farfeleder 		evalstring(p, 0);
5124b88c807SRodney W. Grimes 	}
5134b88c807SRodney W. Grimes l1:   handler = &loc2;			/* probably unnecessary */
5144b88c807SRodney W. Grimes 	flushall();
5154b88c807SRodney W. Grimes #if JOBS
5164b88c807SRodney W. Grimes 	setjobctl(0);
5174b88c807SRodney W. Grimes #endif
51870df11eaSJilles Tjoelker l2:   _exit(exiting_exitstatus);
5194b88c807SRodney W. Grimes }
520