1 /* $OpenBSD: uthread_find_thread.c,v 1.5 2001/12/11 00:19:47 fgsch Exp $ */
2 /*
3 * Copyright (c) 1998 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. All advertising materials mentioning features or use of this software
15 * must display the following acknowledgement:
16 * This product includes software developed by John Birrell.
17 * 4. Neither the name of the author nor the names of any co-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 JOHN BIRRELL 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 AUTHOR 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 * $FreeBSD: uthread_find_thread.c,v 1.5 1999/08/28 00:03:32 peter Exp $
34 */
35 #include <errno.h>
36 #ifdef _THREAD_SAFE
37 #include <pthread.h>
38 #include "pthread_private.h"
39
40 /* Find a thread in the linked list of active threads: */
41 int
_find_thread(pthread_t pthread)42 _find_thread(pthread_t pthread)
43 {
44 pthread_t pthread1;
45
46 /* Check if the caller has specified an invalid thread: */
47 if (pthread == NULL || pthread->magic != PTHREAD_MAGIC)
48 /* Invalid thread: */
49 return(EINVAL);
50
51 /*
52 * Defer signals to protect the thread list from access
53 * by the signal handler:
54 */
55 _thread_kern_sig_defer();
56
57 /* Search for the specified thread: */
58 TAILQ_FOREACH(pthread1, &_thread_list, tle) {
59 if (pthread == pthread1)
60 break;
61 }
62
63 /* Undefer and handle pending signals, yielding if necessary: */
64 _thread_kern_sig_undefer();
65
66 /* Return zero if the thread exists: */
67 return ((pthread1 != NULL) ? 0:ESRCH);
68 }
69 #endif
70