1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
23 /* All Rights Reserved */
24
25
26 #ident "%Z%%M% %I% %E% SMI" /* SVr4.0 1.5 */
27
28 #include "signal.h"
29
30 #include "lpadmin.h"
31
32 static int trapping = -1; /* -1 means first time */
33
34 static
35 #ifdef SIGPOLL
36 void
37 #else
38 int
39 #endif
40 (*old_sighup)(),
41 (*old_sigint)(),
42 (*old_sigquit)(),
43 (*old_sigterm)();
44
45 /**
46 ** catch() - CLEAN UP AFTER SIGNAL
47 **/
48
49 static void
catch(sig)50 catch (sig)
51 {
52 (void)signal (SIGHUP, SIG_IGN);
53 (void)signal (SIGINT, SIG_IGN);
54 (void)signal (SIGQUIT, SIG_IGN);
55 (void)signal (SIGTERM, SIG_IGN);
56 done (1);
57 }
58
59 /**
60 ** trap_signals() - SET SIGNALS TO BE CAUGHT FOR CLEAN EXIT
61 **/
62
trap_signals()63 void trap_signals ()
64 {
65 switch (trapping) {
66
67 case -1: /* first time */
68
69 #define SETSIG(SIG) \
70 if (signal(SIG, SIG_IGN) != SIG_IGN) \
71 signal (SIG, catch);
72
73 SETSIG (SIGHUP);
74 SETSIG (SIGINT);
75 SETSIG (SIGQUIT);
76 SETSIG (SIGTERM);
77 break;
78
79 case 0: /* currently ignoring */
80 signal (SIGHUP, old_sighup);
81 signal (SIGINT, old_sigint);
82 signal (SIGQUIT, old_sigquit);
83 signal (SIGTERM, old_sigterm);
84 trapping = 1;
85 break;
86
87 case 1: /* already trapping */
88 break;
89
90 }
91 return;
92 }
93
94 /**
95 ** ignore_signals() - SET SIGNALS TO BE IGNORED FOR CRITICAL SECTIONS
96 **/
97
ignore_signals()98 void ignore_signals ()
99 {
100 switch (trapping) {
101
102 case -1: /* first time */
103 trap_signals ();
104 /*fall through*/
105
106 case 1: /* currently trapping */
107 old_sighup = signal(SIGHUP, SIG_IGN);
108 old_sigint = signal(SIGINT, SIG_IGN);
109 old_sigquit = signal(SIGQUIT, SIG_IGN);
110 old_sigterm = signal(SIGTERM, SIG_IGN);
111 trapping = 0;
112 break;
113
114 case 0: /* already ignoring */
115 break;
116
117 }
118 return;
119 }
120