sig.c revision 296435 
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
38static char sccsid[] = "@(#)sig.c	8.1 (Berkeley) 6/4/93";
39#else
40__RCSID("$NetBSD: sig.c,v 1.17 2011/07/28 20:50:55 christos Exp $");
41#endif
42#endif /* not lint && not SCCSID */
43#include <sys/cdefs.h>
44__FBSDID("$FreeBSD: head/lib/libedit/sig.c 296435 2016-03-06 21:32:54Z pfg $");
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 "el.h"
52#include <stdlib.h>
53
54private EditLine *sel = NULL;
55
56private const int sighdl[] = {
57#define	_DO(a)	(a),
58	ALLSIGS
59#undef	_DO
60	- 1
61};
62
63private void sig_handler(int);
64
65/* sig_handler():
66 *	This is the handler called for all signals
67 *	XXX: we cannot pass any data so we just store the old editline
68 *	state in a private variable
69 */
70private void
71sig_handler(int signo)
72{
73	int i;
74	sigset_t nset, oset;
75
76	(void) sigemptyset(&nset);
77	(void) sigaddset(&nset, signo);
78	(void) sigprocmask(SIG_BLOCK, &nset, &oset);
79
80	sel->el_signal->sig_no = signo;
81
82	switch (signo) {
83	case SIGCONT:
84		tty_rawmode(sel);
85		if (ed_redisplay(sel, 0) == CC_REFRESH)
86			re_refresh(sel);
87		terminal__flush(sel);
88		break;
89
90	case SIGWINCH:
91		el_resize(sel);
92		break;
93
94	default:
95		tty_cookedmode(sel);
96		break;
97	}
98
99	for (i = 0; sighdl[i] != -1; i++)
100		if (signo == sighdl[i])
101			break;
102
103	(void) sigaction(signo, &sel->el_signal->sig_action[i], NULL);
104	sel->el_signal->sig_action[i].sa_handler = SIG_ERR;
105	sel->el_signal->sig_action[i].sa_flags = 0;
106	sigemptyset(&sel->el_signal->sig_action[i].sa_mask);
107	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
108	(void) kill(0, signo);
109}
110
111
112/* sig_init():
113 *	Initialize all signal stuff
114 */
115protected int
116sig_init(EditLine *el)
117{
118	size_t i;
119	sigset_t *nset, oset;
120
121	el->el_signal = el_malloc(sizeof(*el->el_signal));
122	if (el->el_signal == NULL)
123		return -1;
124
125	nset = &el->el_signal->sig_set;
126	(void) sigemptyset(nset);
127#define	_DO(a) (void) sigaddset(nset, a);
128	ALLSIGS
129#undef	_DO
130	(void) sigprocmask(SIG_BLOCK, nset, &oset);
131
132	for (i = 0; sighdl[i] != -1; i++) {
133		el->el_signal->sig_action[i].sa_handler = SIG_ERR;
134		el->el_signal->sig_action[i].sa_flags = 0;
135		sigemptyset(&el->el_signal->sig_action[i].sa_mask);
136	}
137
138	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
139
140	return 0;
141}
142
143
144/* sig_end():
145 *	Clear all signal stuff
146 */
147protected void
148sig_end(EditLine *el)
149{
150
151	el_free(el->el_signal);
152	el->el_signal = NULL;
153}
154
155
156/* sig_set():
157 *	set all the signal handlers
158 */
159protected void
160sig_set(EditLine *el)
161{
162	size_t i;
163	sigset_t oset;
164	struct sigaction osa, nsa;
165
166	nsa.sa_handler = sig_handler;
167	nsa.sa_flags = 0;
168	sigemptyset(&nsa.sa_mask);
169
170	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
171
172	for (i = 0; sighdl[i] != -1; i++) {
173		/* This could happen if we get interrupted */
174		if (sigaction(sighdl[i], &nsa, &osa) != -1 &&
175		    osa.sa_handler != sig_handler)
176			el->el_signal->sig_action[i] = osa;
177	}
178	sel = el;
179	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
180}
181
182
183/* sig_clr():
184 *	clear all the signal handlers
185 */
186protected void
187sig_clr(EditLine *el)
188{
189	size_t i;
190	sigset_t oset;
191
192	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
193
194	for (i = 0; sighdl[i] != -1; i++)
195		if (el->el_signal->sig_action[i].sa_handler != SIG_ERR)
196			(void)sigaction(sighdl[i],
197			    &el->el_signal->sig_action[i], NULL);
198
199	sel = NULL;		/* we are going to die if the handler is
200				 * called */
201	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
202}
203