thr_kill.c revision 41165 
1/*
2 * Copyright (c) 1997 John Birrell <jb@cimlogic.com.au>.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by John Birrell.
16 * 4. Neither the name of the author nor the names of any co-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 JOHN BIRRELL 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 */
33#include <errno.h>
34#include <signal.h>
35#ifdef _THREAD_SAFE
36#include <pthread.h>
37#include "pthread_private.h"
38
39int
40pthread_kill(pthread_t pthread, int sig)
41{
42	int ret;
43
44	/* Check for invalid signal numbers: */
45	if (sig < 0 || sig >= NSIG)
46		/* Invalid signal: */
47		ret = EINVAL;
48
49	/* Ignored signals get dropped on the floor. */
50	else if (_thread_sigact[sig - 1].sa_handler == SIG_IGN)
51		ret = 0;
52
53	/* Find the thread in the list of active threads: */
54	else if ((ret = _find_thread(pthread)) == 0) {
55		switch (pthread->state) {
56		case PS_SIGSUSPEND:
57			/*
58			 * Only wake up the thread if the signal is unblocked
59			 * and there is a handler installed for the signal.
60			 */
61			if (!sigismember(&pthread->sigmask, sig) &&
62			    _thread_sigact[sig - 1].sa_handler != SIG_DFL) {
63				/* Change the state of the thread to run: */
64				PTHREAD_NEW_STATE(pthread,PS_RUNNING);
65
66				/* Return the signal number: */
67				pthread->signo = sig;
68			}
69			/* Increment the pending signal count: */
70			sigaddset(&pthread->sigpend,sig);
71			break;
72
73		case PS_SIGWAIT:
74			/* Wake up the thread if the signal is blocked. */
75			if (sigismember(pthread->data.sigwait, sig)) {
76				/* Change the state of the thread to run: */
77				PTHREAD_NEW_STATE(pthread,PS_RUNNING);
78
79				/* Return the signal number: */
80				pthread->signo = sig;
81			} else
82				/* Increment the pending signal count. */
83				sigaddset(&pthread->sigpend,sig);
84			break;
85
86		case PS_SELECT_WAIT:
87		case PS_FDR_WAIT:
88		case PS_FDW_WAIT:
89		case PS_SLEEP_WAIT:
90			if (!sigismember(&pthread->sigmask, sig) &&
91			    (_thread_sigact[sig - 1].sa_handler != SIG_IGN)) {
92				/* Flag the operation as interrupted: */
93				pthread->interrupted = 1;
94
95				/* Change the state of the thread to run: */
96				PTHREAD_NEW_STATE(pthread,PS_RUNNING);
97
98				/* Return the signal number: */
99				pthread->signo = sig;
100			} else {
101				/* Increment the pending signal count: */
102				sigaddset(&pthread->sigpend,sig);
103			}
104			break;
105
106		default:
107			/* Increment the pending signal count: */
108			sigaddset(&pthread->sigpend,sig);
109			break;
110		}
111	}
112
113	/* Return the completion status: */
114	return (ret);
115}
116#endif
117