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
38static 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: stable/11/lib/libedit/sig.c 313981 2017-02-20 03:33:59Z 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 <errno.h>
52#include <stdlib.h>
53
54#include "el.h"
55#include "common.h"
56
57private EditLine *sel = NULL;
58
59private const int sighdl[] = {
60#define	_DO(a)	(a),
61	ALLSIGS
62#undef	_DO
63	- 1
64};
65
66private 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 */
73private void
74sig_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 */
120protected int
121sig_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 */
152protected void
153sig_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 */
164protected void
165sig_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 */
191protected void
192sig_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