xref: /freebsd-12.1/lib/libedit/sig.c (revision 1f37f0f1)
1 /*	$NetBSD: sig.c,v 1.24 2016/02/16 19:08:41 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Christos Zoulas of Cornell University.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include "config.h"
36 #if !defined(lint) && !defined(SCCSID)
37 #if 0
38 static char sccsid[] = "@(#)sig.c	8.1 (Berkeley) 6/4/93";
39 #else
40 __RCSID("$NetBSD: sig.c,v 1.24 2016/02/16 19:08:41 christos Exp $");
41 #endif
42 #endif /* not lint && not SCCSID */
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 /*
47  * sig.c: Signal handling stuff.
48  *	  our policy is to trap all signals, set a good state
49  *	  and pass the ball to our caller.
50  */
51 #include <errno.h>
52 #include <stdlib.h>
53 
54 #include "el.h"
55 #include "common.h"
56 
57 private EditLine *sel = NULL;
58 
59 private const int sighdl[] = {
60 #define	_DO(a)	(a),
61 	ALLSIGS
62 #undef	_DO
63 	- 1
64 };
65 
66 private void sig_handler(int);
67 
68 /* sig_handler():
69  *	This is the handler called for all signals
70  *	XXX: we cannot pass any data so we just store the old editline
71  *	state in a private variable
72  */
73 private void
sig_handler(int signo)74 sig_handler(int signo)
75 {
76 	int i, save_errno;
77 	sigset_t nset, oset;
78 
79 	save_errno = errno;
80 	(void) sigemptyset(&nset);
81 	(void) sigaddset(&nset, signo);
82 	(void) sigprocmask(SIG_BLOCK, &nset, &oset);
83 
84 	sel->el_signal->sig_no = signo;
85 
86 	switch (signo) {
87 	case SIGCONT:
88 		tty_rawmode(sel);
89 		if (ed_redisplay(sel, 0) == CC_REFRESH)
90 			re_refresh(sel);
91 		terminal__flush(sel);
92 		break;
93 
94 	case SIGWINCH:
95 		el_resize(sel);
96 		break;
97 
98 	default:
99 		tty_cookedmode(sel);
100 		break;
101 	}
102 
103 	for (i = 0; sighdl[i] != -1; i++)
104 		if (signo == sighdl[i])
105 			break;
106 
107 	(void) sigaction(signo, &sel->el_signal->sig_action[i], NULL);
108 	sel->el_signal->sig_action[i].sa_handler = SIG_ERR;
109 	sel->el_signal->sig_action[i].sa_flags = 0;
110 	sigemptyset(&sel->el_signal->sig_action[i].sa_mask);
111 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
112 	(void) kill(0, signo);
113 	errno = save_errno;
114 }
115 
116 
117 /* sig_init():
118  *	Initialize all signal stuff
119  */
120 protected int
sig_init(EditLine * el)121 sig_init(EditLine *el)
122 {
123 	size_t i;
124 	sigset_t *nset, oset;
125 
126 	el->el_signal = el_malloc(sizeof(*el->el_signal));
127 	if (el->el_signal == NULL)
128 		return -1;
129 
130 	nset = &el->el_signal->sig_set;
131 	(void) sigemptyset(nset);
132 #define	_DO(a) (void) sigaddset(nset, a);
133 	ALLSIGS
134 #undef	_DO
135 	(void) sigprocmask(SIG_BLOCK, nset, &oset);
136 
137 	for (i = 0; sighdl[i] != -1; i++) {
138 		el->el_signal->sig_action[i].sa_handler = SIG_ERR;
139 		el->el_signal->sig_action[i].sa_flags = 0;
140 		sigemptyset(&el->el_signal->sig_action[i].sa_mask);
141 	}
142 
143 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
144 
145 	return 0;
146 }
147 
148 
149 /* sig_end():
150  *	Clear all signal stuff
151  */
152 protected void
sig_end(EditLine * el)153 sig_end(EditLine *el)
154 {
155 
156 	el_free(el->el_signal);
157 	el->el_signal = NULL;
158 }
159 
160 
161 /* sig_set():
162  *	set all the signal handlers
163  */
164 protected void
sig_set(EditLine * el)165 sig_set(EditLine *el)
166 {
167 	size_t i;
168 	sigset_t oset;
169 	struct sigaction osa, nsa;
170 
171 	nsa.sa_handler = sig_handler;
172 	nsa.sa_flags = 0;
173 	sigemptyset(&nsa.sa_mask);
174 
175 	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
176 
177 	for (i = 0; sighdl[i] != -1; i++) {
178 		/* This could happen if we get interrupted */
179 		if (sigaction(sighdl[i], &nsa, &osa) != -1 &&
180 		    osa.sa_handler != sig_handler)
181 			el->el_signal->sig_action[i] = osa;
182 	}
183 	sel = el;
184 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
185 }
186 
187 
188 /* sig_clr():
189  *	clear all the signal handlers
190  */
191 protected void
sig_clr(EditLine * el)192 sig_clr(EditLine *el)
193 {
194 	size_t i;
195 	sigset_t oset;
196 
197 	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
198 
199 	for (i = 0; sighdl[i] != -1; i++)
200 		if (el->el_signal->sig_action[i].sa_handler != SIG_ERR)
201 			(void)sigaction(sighdl[i],
202 			    &el->el_signal->sig_action[i], NULL);
203 
204 	sel = NULL;		/* we are going to die if the handler is
205 				 * called */
206 	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
207 }
208