contrib/tcsh-6/tc.sig.c

   1 /*
   2  * tc.sig.c: Signal routine emulations
   3  */
   4 /*-
   5  * Copyright (c) 1980, 1991 The Regents of the University of California.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the name of the University nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32 #include "sh.h"
  33 #include "tc.wait.h"
  34
  35 void
  36 sigset_interrupting(int sig, void (*fn) (int))
  37 {
  38     struct sigaction act;
  39
  40     act.sa_handler = fn;
  41     sigemptyset(&act.sa_mask);
  42     act.sa_flags = 0;
  43     if (sigaction(sig, &act, NULL) == 0) {
  44         sigset_t set;
  45         sigemptyset(&set);
  46         sigaddset(&set, sig);
  47         sigprocmask(SIG_UNBLOCK, &set, NULL);
  48     }
  49 }
  50
  51 static volatile sig_atomic_t alrmcatch_pending; /* = 0; */
  52 static volatile sig_atomic_t pchild_pending; /* = 0; */
  53 static volatile sig_atomic_t phup_pending; /* = 0; */
  54 static volatile sig_atomic_t pintr_pending; /* = 0; */
  55 int alrmcatch_disabled; /* = 0; */
  56 int phup_disabled; /* = 0; */
  57 int pchild_disabled; /* = 0; */
  58 int pintr_disabled; /* = 0; */
  59
  60 int
  61 handle_pending_signals(void)
  62 {
  63     int rv = 0;
  64     if (!phup_disabled && phup_pending) {
  65         phup_pending = 0;
  66         handle_interrupt++;
  67         phup();
  68         handle_interrupt--;
  69     }
  70     if (!pintr_disabled && pintr_pending) {
  71         pintr_pending = 0;
  72         handle_interrupt++;
  73         pintr();
  74         handle_interrupt--;
  75         rv = 1;
  76     }
  77     if (!pchild_disabled && pchild_pending) {
  78         pchild_pending = 0;
  79         handle_interrupt++;
  80         pchild();
  81         handle_interrupt--;
  82     }
  83     if (!alrmcatch_disabled && alrmcatch_pending) {
  84         alrmcatch_pending = 0;
  85         handle_interrupt++;
  86         alrmcatch();
  87         handle_interrupt--;
  88     }
  89     return rv;
  90 }
  91
  92 void
  93 queue_alrmcatch(int sig)
  94 {
  95     USE(sig);
  96     alrmcatch_pending = 1;
  97 }
  98
  99 void
 100 queue_pchild(int sig)
 101 {
 102     USE(sig);
 103     pchild_pending = 1;
 104 }
 105
 106 void
 107 queue_phup(int sig)
 108 {
 109     USE(sig);
 110     phup_pending = 1;
 111 }
 112
 113 void
 114 queue_pintr(int sig)
 115 {
 116     USE(sig);
 117     pintr_pending = 1;
 118 }
 119
 120 void
 121 disabled_cleanup(void *xdisabled)
 122 {
 123     int *disabled;
 124
 125     disabled = xdisabled;
 126     if (--*disabled == 0)
 127         handle_pending_signals();
 128 }
 129
 130 void
 131 pintr_disabled_restore(void *xold)
 132 {
 133     int *old;
 134
 135     old = xold;
 136     pintr_disabled = *old;
 137 }
 138
 139 void
 140 pintr_push_enable(int *saved)
 141 {
 142     *saved = pintr_disabled;
 143     pintr_disabled = 0;
 144     cleanup_push(saved, pintr_disabled_restore);
 145     handle_pending_signals();
 146 }