1 //depot/projects/kse/lib/libpthread/thread/thr_sigwait.c#1 - branch change 15154 (text+ko)
2 /*
3  * Copyright (c) 1997 John Birrell <jb@cimlogic.com.au>.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the author nor the names of any co-contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD: stable/10/lib/libkse/thread/thr_sigwait.c 174689 2007-12-16 23:29:57Z deischen $
31  */
32 
33 #include "namespace.h"
34 #include <signal.h>
35 #include <sys/param.h>
36 #include <sys/signalvar.h>
37 #include <errno.h>
38 #include <pthread.h>
39 #include "un-namespace.h"
40 #include "thr_private.h"
41 
42 int	__sigtimedwait(const sigset_t *set, siginfo_t *info,
43 	    const struct timespec *timeout);
44 int	__sigwaitinfo(const sigset_t *set, siginfo_t *info);
45 int	__sigwait(const sigset_t *set, int *sig);
46 int	_sigtimedwait(const sigset_t *set, siginfo_t *info,
47 	    const struct timespec *timeout);
48 int	_sigwaitinfo(const sigset_t *set, siginfo_t *info);
49 int	_sigwait(const sigset_t *set, int *sig);
50 
51 __weak_reference(__sigwait, sigwait);
52 __weak_reference(__sigtimedwait, sigtimedwait);
53 __weak_reference(__sigwaitinfo, sigwaitinfo);
54 
55 static int
lib_sigtimedwait(const sigset_t * set,siginfo_t * info,const struct timespec * timeout)56 lib_sigtimedwait(const sigset_t *set, siginfo_t *info,
57 	const struct timespec *timeout)
58 {
59 	struct pthread	*curthread = _get_curthread();
60 	int		ret = 0;
61 	int		i;
62 	struct sigwait_data waitdata;
63 	sigset_t	waitset;
64 	kse_critical_t  crit;
65 	siginfo_t	siginfo;
66 
67 	if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
68 		if (info == NULL)
69 			info = &siginfo;
70 		return (__sys_sigtimedwait(set, info, timeout));
71 	}
72 
73 	/*
74 	 * Initialize the set of signals that will be waited on:
75 	 */
76 	waitset = *set;
77 
78 	/* These signals can't be waited on. */
79 	SIGDELSET(waitset, SIGKILL);
80 	SIGDELSET(waitset, SIGSTOP);
81 
82 	/*
83 	 * POSIX says that the _application_ must explicitly install
84 	 * a dummy handler for signals that are SIG_IGN in order
85 	 * to sigwait on them. Note that SIG_IGN signals are left in
86 	 * the mask because a subsequent sigaction could enable an
87 	 * ignored signal.
88 	 */
89 
90 	crit = _kse_critical_enter();
91 	KSE_SCHED_LOCK(curthread->kse, curthread->kseg);
92 	for (i = 1; i <= _SIG_MAXSIG; ++i) {
93 		if (SIGISMEMBER(waitset, i) &&
94 		    SIGISMEMBER(curthread->sigpend, i)) {
95 			SIGDELSET(curthread->sigpend, i);
96 			siginfo = curthread->siginfo[i - 1];
97 			KSE_SCHED_UNLOCK(curthread->kse,
98 				curthread->kseg);
99 			_kse_critical_leave(crit);
100 			ret = i;
101 			goto OUT;
102 		}
103 	}
104 	curthread->timeout = 0;
105 	curthread->interrupted = 0;
106 	_thr_set_timeout(timeout);
107 	/* Wait for a signal: */
108 	siginfo.si_signo = 0;
109 	waitdata.waitset = &waitset;
110 	waitdata.siginfo = &siginfo;
111 	curthread->data.sigwait = &waitdata;
112 	THR_SET_STATE(curthread, PS_SIGWAIT);
113 	_thr_sched_switch_unlocked(curthread);
114 	/*
115 	 * Return the signal number to the caller:
116 	 */
117 	if (siginfo.si_signo > 0) {
118 		ret = siginfo.si_signo;
119 	} else {
120 		if (curthread->interrupted)
121 			errno = EINTR;
122 		else if (curthread->timeout)
123 			errno = EAGAIN;
124 		ret = -1;
125 	}
126 	curthread->timeout = 0;
127 	curthread->interrupted = 0;
128 	/*
129 	 * Probably unnecessary, but since it's in a union struct
130 	 * we don't know how it could be used in the future.
131 	 */
132 	curthread->data.sigwait = NULL;
133 
134 OUT:
135 	if (ret > 0 && info != NULL)
136 		*info = siginfo;
137 
138 	return (ret);
139 }
140 
141 int
__sigtimedwait(const sigset_t * set,siginfo_t * info,const struct timespec * timeout)142 __sigtimedwait(const sigset_t *set, siginfo_t *info,
143 	const struct timespec * timeout)
144 {
145 	struct pthread	*curthread = _get_curthread();
146 	int ret;
147 
148 	_thr_cancel_enter(curthread);
149 	ret = lib_sigtimedwait(set, info, timeout);
150 	_thr_cancel_leave(curthread, 1);
151 	return (ret);
152 }
153 
_sigtimedwait(const sigset_t * set,siginfo_t * info,const struct timespec * timeout)154 int _sigtimedwait(const sigset_t *set, siginfo_t *info,
155 	const struct timespec * timeout)
156 {
157 	return lib_sigtimedwait(set, info, timeout);
158 }
159 
160 int
__sigwaitinfo(const sigset_t * set,siginfo_t * info)161 __sigwaitinfo(const sigset_t *set, siginfo_t *info)
162 {
163 	struct pthread	*curthread = _get_curthread();
164 	int ret;
165 
166 	_thr_cancel_enter(curthread);
167 	ret = lib_sigtimedwait(set, info, NULL);
168 	_thr_cancel_leave(curthread, 1);
169 	return (ret);
170 }
171 
172 int
_sigwaitinfo(const sigset_t * set,siginfo_t * info)173 _sigwaitinfo(const sigset_t *set, siginfo_t *info)
174 {
175 	return lib_sigtimedwait(set, info, NULL);
176 }
177 
178 int
__sigwait(const sigset_t * set,int * sig)179 __sigwait(const sigset_t *set, int *sig)
180 {
181 	struct pthread	*curthread = _get_curthread();
182 	int ret;
183 
184 	_thr_cancel_enter(curthread);
185 	ret = lib_sigtimedwait(set, NULL, NULL);
186 	if (ret > 0) {
187 		*sig = ret;
188 		ret = 0;
189 	} else {
190 		ret = errno;
191 	}
192 	_thr_cancel_leave(curthread, 1);
193 	return (ret);
194 }
195 
196 int
_sigwait(const sigset_t * set,int * sig)197 _sigwait(const sigset_t *set, int *sig)
198 {
199 	int ret;
200 
201 	ret = lib_sigtimedwait(set, NULL, NULL);
202 	if (ret > 0) {
203 		*sig = ret;
204 		ret = 0;
205 	} else {
206 		ret = errno;
207 	}
208 	return (ret);
209 }
210 
211