1 /*	$NetBSD: sig.c,v 1.17 2011/07/28 20:50:55 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 #endif
41 #endif /* not lint && not SCCSID */
42 
43 /*
44  * sig.c: Signal handling stuff.
45  *	  our policy is to trap all signals, set a good state
46  *	  and pass the ball to our caller.
47  */
48 #include "el.h"
49 #include <stdlib.h>
50 
51 private EditLine *sel = NULL;
52 
53 private const int sighdl[] = {
54 #define	_DO(a)	(a),
55 	ALLSIGS
56 #undef	_DO
57 	- 1
58 };
59 
60 private void sig_handler(int);
61 
62 /* sig_handler():
63  *	This is the handler called for all signals
64  *	XXX: we cannot pass any data so we just store the old editline
65  *	state in a private variable
66  */
67 private void
sig_handler(int signo)68 sig_handler(int signo)
69 {
70 	int i;
71 	sigset_t nset, oset;
72 
73 	(void) sigemptyset(&nset);
74 	(void) sigaddset(&nset, signo);
75 	(void) sigprocmask(SIG_BLOCK, &nset, &oset);
76 
77 	sel->el_signal->sig_no = signo;
78 
79 	switch (signo) {
80 	case SIGCONT:
81 		tty_rawmode(sel);
82 		if (ed_redisplay(sel, 0) == CC_REFRESH)
83 			re_refresh(sel);
84 		terminal__flush(sel);
85 		break;
86 
87 	case SIGWINCH:
88 		el_resize(sel);
89 		break;
90 
91 	default:
92 		tty_cookedmode(sel);
93 		break;
94 	}
95 
96 	for (i = 0; sighdl[i] != -1; i++)
97 		if (signo == sighdl[i])
98 			break;
99 
100 	(void) sigaction(signo, &sel->el_signal->sig_action[i], NULL);
101 	sel->el_signal->sig_action[i].sa_handler = SIG_ERR;
102 	sel->el_signal->sig_action[i].sa_flags = 0;
103 	sigemptyset(&sel->el_signal->sig_action[i].sa_mask);
104 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
105 	(void) kill(0, signo);
106 }
107 
108 
109 /* sig_init():
110  *	Initialize all signal stuff
111  */
112 protected int
sig_init(EditLine * el)113 sig_init(EditLine *el)
114 {
115 	size_t i;
116 	sigset_t *nset, oset;
117 
118 	el->el_signal = el_malloc(sizeof(*el->el_signal));
119 	if (el->el_signal == NULL)
120 		return -1;
121 
122 	nset = &el->el_signal->sig_set;
123 	(void) sigemptyset(nset);
124 #define	_DO(a) (void) sigaddset(nset, a);
125 	ALLSIGS
126 #undef	_DO
127 	(void) sigprocmask(SIG_BLOCK, nset, &oset);
128 
129 	for (i = 0; sighdl[i] != -1; i++) {
130 		el->el_signal->sig_action[i].sa_handler = SIG_ERR;
131 		el->el_signal->sig_action[i].sa_flags = 0;
132 		sigemptyset(&el->el_signal->sig_action[i].sa_mask);
133 	}
134 
135 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
136 
137 	return 0;
138 }
139 
140 
141 /* sig_end():
142  *	Clear all signal stuff
143  */
144 protected void
sig_end(EditLine * el)145 sig_end(EditLine *el)
146 {
147 
148 	el_free(el->el_signal);
149 	el->el_signal = NULL;
150 }
151 
152 
153 /* sig_set():
154  *	set all the signal handlers
155  */
156 protected void
sig_set(EditLine * el)157 sig_set(EditLine *el)
158 {
159 	size_t i;
160 	sigset_t oset;
161 	struct sigaction osa, nsa;
162 
163 	nsa.sa_handler = sig_handler;
164 	nsa.sa_flags = 0;
165 	sigemptyset(&nsa.sa_mask);
166 
167 	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
168 
169 	for (i = 0; sighdl[i] != -1; i++) {
170 		/* This could happen if we get interrupted */
171 		if (sigaction(sighdl[i], &nsa, &osa) != -1 &&
172 		    osa.sa_handler != sig_handler)
173 			el->el_signal->sig_action[i] = osa;
174 	}
175 	sel = el;
176 	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
177 }
178 
179 
180 /* sig_clr():
181  *	clear all the signal handlers
182  */
183 protected void
sig_clr(EditLine * el)184 sig_clr(EditLine *el)
185 {
186 	size_t i;
187 	sigset_t oset;
188 
189 	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
190 
191 	for (i = 0; sighdl[i] != -1; i++)
192 		if (el->el_signal->sig_action[i].sa_handler != SIG_ERR)
193 			(void)sigaction(sighdl[i],
194 			    &el->el_signal->sig_action[i], NULL);
195 
196 	sel = NULL;		/* we are going to die if the handler is
197 				 * called */
198 	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
199 }
200