lib/libedit/sig.c

   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 __RCSID("$NetBSD: sig.c,v 1.17 2011/07/28 20:50:55 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                 terminal__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(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 }