1  /*	$NetBSD: sig.c,v 1.15 2009/02/19 15:20:22 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 1.15 2009/02/19 15:20:22 christos Exp $");
 41  #endif
 42  #endif /* not lint && not SCCSID */
 43  
 44  /*
 45   * sig.c: Signal handling stuff.
 46   *	  our policy is to trap all signals, set a good state
 47   *	  and pass the ball to our caller.
 48   */
 49  #include "el.h"
 50  #include <stdlib.h>
 51  
 52  private EditLine *sel = NULL;
 53  
 54  private const int sighdl[] = {
 55  #define	_DO(a)	(a),
 56  	ALLSIGS
 57  #undef	_DO
 58  	- 1
 59  };
 60  
 61  private void sig_handler(int);
 62  
 63  /* sig_handler():
 64   *	This is the handler called for all signals
 65   *	XXX: we cannot pass any data so we just store the old editline
 66   *	state in a private variable
 67   */
 68  private void
 69  sig_handler(int signo)
 70  {
 71  	int i;
 72  	sigset_t nset, oset;
 73  
 74  	(void) sigemptyset(&nset);
 75  	(void) sigaddset(&nset, signo);
 76  	(void) sigprocmask(SIG_BLOCK, &nset, &oset);
 77  
 78  	sel->el_signal->sig_no = signo;
 79  
 80  	switch (signo) {
 81  	case SIGCONT:
 82  		tty_rawmode(sel);
 83  		if (ed_redisplay(sel, 0) == CC_REFRESH)
 84  			re_refresh(sel);
 85  		term__flush(sel);
 86  		break;
 87  
 88  	case SIGWINCH:
 89  		el_resize(sel);
 90  		break;
 91  
 92  	default:
 93  		tty_cookedmode(sel);
 94  		break;
 95  	}
 96  
 97  	for (i = 0; sighdl[i] != -1; i++)
 98  		if (signo == sighdl[i])
 99  			break;
100  
101  	(void) sigaction(signo, &sel->el_signal->sig_action[i], NULL);
102  	sel->el_signal->sig_action[i].sa_handler = SIG_ERR;
103  	sel->el_signal->sig_action[i].sa_flags = 0;
104  	sigemptyset(&sel->el_signal->sig_action[i].sa_mask);
105  	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
106  	(void) kill(0, signo);
107  }
108  
109  
110  /* sig_init():
111   *	Initialize all signal stuff
112   */
113  protected int
114  sig_init(EditLine *el)
115  {
116  	size_t i;
117  	sigset_t *nset, oset;
118  
119  	el->el_signal = el_malloc(sizeof(*el->el_signal));
120  	if (el->el_signal == NULL)
121  		return -1;
122  
123  	nset = &el->el_signal->sig_set;
124  	(void) sigemptyset(nset);
125  #define	_DO(a) (void) sigaddset(nset, a);
126  	ALLSIGS
127  #undef	_DO
128  	(void) sigprocmask(SIG_BLOCK, nset, &oset);
129  
130  	for (i = 0; sighdl[i] != -1; i++) {
131  		el->el_signal->sig_action[i].sa_handler = SIG_ERR;
132  		el->el_signal->sig_action[i].sa_flags = 0;
133  		sigemptyset(&el->el_signal->sig_action[i].sa_mask);
134  	}
135  
136  	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
137  
138  	return 0;
139  }
140  
141  
142  /* sig_end():
143   *	Clear all signal stuff
144   */
145  protected void
146  sig_end(EditLine *el)
147  {
148  
149  	el_free((ptr_t) el->el_signal);
150  	el->el_signal = NULL;
151  }
152  
153  
154  /* sig_set():
155   *	set all the signal handlers
156   */
157  protected void
158  sig_set(EditLine *el)
159  {
160  	size_t i;
161  	sigset_t oset;
162  	struct sigaction osa, nsa;
163  
164  	nsa.sa_handler = sig_handler;
165  	nsa.sa_flags = 0;
166  	sigemptyset(&nsa.sa_mask);
167  
168  	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
169  
170  	for (i = 0; sighdl[i] != -1; i++) {
171  		/* This could happen if we get interrupted */
172  		if (sigaction(sighdl[i], &nsa, &osa) != -1 &&
173  		    osa.sa_handler != sig_handler)
174  			el->el_signal->sig_action[i] = osa;
175  	}
176  	sel = el;
177  	(void) sigprocmask(SIG_SETMASK, &oset, NULL);
178  }
179  
180  
181  /* sig_clr():
182   *	clear all the signal handlers
183   */
184  protected void
185  sig_clr(EditLine *el)
186  {
187  	size_t i;
188  	sigset_t oset;
189  
190  	(void) sigprocmask(SIG_BLOCK, &el->el_signal->sig_set, &oset);
191  
192  	for (i = 0; sighdl[i] != -1; i++)
193  		if (el->el_signal->sig_action[i].sa_handler != SIG_ERR)
194  			(void)sigaction(sighdl[i],
195  			    &el->el_signal->sig_action[i], NULL);
196  
197  	sel = NULL;		/* we are going to die if the handler is
198  				 * called */
199  	(void)sigprocmask(SIG_SETMASK, &oset, NULL);
200  }