xref: /freebsd/lib/libthr/thread/thr_detach.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*
2  * Copyright (c) 1995 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 AUTHOR 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  * $FreeBSD$
33  */
34 #include <errno.h>
35 #include <pthread.h>
36 #include <stdlib.h>
37 #include "thr_private.h"
38 
39 __weak_reference(_pthread_detach, pthread_detach);
40 
41 int
42 _pthread_detach(pthread_t pthread)
43 {
44 	if (pthread == NULL || pthread->magic != PTHREAD_MAGIC)
45 		return (EINVAL);
46 
47 	UMTX_LOCK(&pthread->lock);
48 
49 	if (pthread->attr.flags & PTHREAD_DETACHED) {
50 		UMTX_UNLOCK(&pthread->lock);
51 		return (EINVAL);
52 	}
53 
54 	pthread->attr.flags |= PTHREAD_DETACHED;
55 
56 	/* Check if there is a joiner: */
57 	if (pthread->joiner != NULL) {
58 		struct pthread	*joiner = pthread->joiner;
59 		_thread_critical_enter(joiner);
60 
61 		/* Make the thread runnable: */
62 		PTHREAD_NEW_STATE(joiner, PS_RUNNING);
63 
64 		/* Set the return value for the woken thread: */
65 		joiner->join_status.error = ESRCH;
66 		joiner->join_status.ret = NULL;
67 		joiner->join_status.thread = NULL;
68 
69 		/*
70 		 * Disconnect the joiner from the thread being detached:
71 		 */
72 		pthread->joiner = NULL;
73 		_thread_critical_exit(joiner);
74 	}
75 
76 	UMTX_UNLOCK(&pthread->lock);
77 
78 	return (0);
79 }
80