xref: /dragonfly/contrib/tcsh-6/tc.sig.c (revision 19fe1c42)
1 /* $Header: /p/tcsh/cvsroot/tcsh/tc.sig.c,v 3.36 2006/08/24 20:56:31 christos Exp $ */
2 /*
3  * tc.sig.c: Signal routine emulations
4  */
5 /*-
6  * Copyright (c) 1980, 1991 The Regents of the University of California.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 #include "sh.h"
34 
35 RCSID("$tcsh: tc.sig.c,v 3.36 2006/08/24 20:56:31 christos Exp $")
36 
37 #include "tc.wait.h"
38 
39 void
40 sigset_interrupting(int sig, void (*fn) (int))
41 {
42     struct sigaction act;
43 
44     act.sa_handler = fn;
45     sigemptyset(&act.sa_mask);
46     act.sa_flags = 0;
47     if (sigaction(sig, &act, NULL) == 0) {
48 	sigset_t set;
49 	sigemptyset(&set);
50 	sigaddset(&set, sig);
51 	sigprocmask(SIG_UNBLOCK, &set, NULL);
52     }
53 }
54 
55 static volatile sig_atomic_t alrmcatch_pending; /* = 0; */
56 static volatile sig_atomic_t pchild_pending; /* = 0; */
57 static volatile sig_atomic_t phup_pending; /* = 0; */
58 static volatile sig_atomic_t pintr_pending; /* = 0; */
59 int alrmcatch_disabled; /* = 0; */
60 int phup_disabled; /* = 0; */
61 int pchild_disabled; /* = 0; */
62 int pintr_disabled; /* = 0; */
63 
64 void
65 handle_pending_signals(void)
66 {
67     if (!phup_disabled && phup_pending) {
68 	phup_pending = 0;
69 	phup();
70     }
71     if (!pintr_disabled && pintr_pending) {
72 	pintr_pending = 0;
73 	pintr();
74     }
75     if (!pchild_disabled && pchild_pending) {
76 	pchild_pending = 0;
77 	pchild();
78     }
79     if (!alrmcatch_disabled && alrmcatch_pending) {
80 	alrmcatch_pending = 0;
81 	alrmcatch();
82     }
83 }
84 
85 void
86 queue_alrmcatch(int sig)
87 {
88     USE(sig);
89     alrmcatch_pending = 1;
90 }
91 
92 void
93 queue_pchild(int sig)
94 {
95     USE(sig);
96     pchild_pending = 1;
97 }
98 
99 void
100 queue_phup(int sig)
101 {
102     USE(sig);
103     phup_pending = 1;
104 }
105 
106 void
107 queue_pintr(int sig)
108 {
109     USE(sig);
110     pintr_pending = 1;
111 }
112 
113 void
114 disabled_cleanup(void *xdisabled)
115 {
116     int *disabled;
117 
118     disabled = xdisabled;
119     if (--*disabled == 0)
120 	handle_pending_signals();
121 }
122 
123 void
124 pintr_disabled_restore(void *xold)
125 {
126     int *old;
127 
128     old = xold;
129     pintr_disabled = *old;
130 }
131 
132 void
133 pintr_push_enable(int *saved)
134 {
135     *saved = pintr_disabled;
136     pintr_disabled = 0;
137     cleanup_push(saved, pintr_disabled_restore);
138     handle_pending_signals();
139 }
140