1 /*
2 * pthread_join.c
3 *
4 * Description:
5 * This translation unit implements functions related to thread
6 * synchronisation.
7 *
8 * --------------------------------------------------------------------------
9 *
10 * Pthreads-win32 - POSIX Threads Library for Win32
11 * Copyright(C) 1998 John E. Bossom
12 * Copyright(C) 1999,2005 Pthreads-win32 contributors
13 *
14 * Contact Email: rpj@callisto.canberra.edu.au
15 *
16 * The current list of contributors is contained
17 * in the file CONTRIBUTORS included with the source
18 * code distribution. The list can also be seen at the
19 * following World Wide Web location:
20 * http://sources.redhat.com/pthreads-win32/contributors.html
21 *
22 * This library is free software; you can redistribute it and/or
23 * modify it under the terms of the GNU Lesser General Public
24 * License as published by the Free Software Foundation; either
25 * version 2 of the License, or (at your option) any later version.
26 *
27 * This library is distributed in the hope that it will be useful,
28 * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
30 * Lesser General Public License for more details.
31 *
32 * You should have received a copy of the GNU Lesser General Public
33 * License along with this library in the file COPYING.LIB;
34 * if not, write to the Free Software Foundation, Inc.,
35 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
36 */
37
38 #include "pthread.h"
39 #include "implement.h"
40
41 /*
42 * Not needed yet, but defining it should indicate clashes with build target
43 * environment that should be fixed.
44 */
45 #if !defined(WINCE)
46 # include <signal.h>
47 #endif
48
49
50 int
pthread_join(pthread_t thread,void ** value_ptr)51 pthread_join (pthread_t thread, void **value_ptr)
52 /*
53 * ------------------------------------------------------
54 * DOCPUBLIC
55 * This function waits for 'thread' to terminate and
56 * returns the thread's exit value if 'value_ptr' is not
57 * NULL. This also detaches the thread on successful
58 * completion.
59 *
60 * PARAMETERS
61 * thread
62 * an instance of pthread_t
63 *
64 * value_ptr
65 * pointer to an instance of pointer to void
66 *
67 *
68 * DESCRIPTION
69 * This function waits for 'thread' to terminate and
70 * returns the thread's exit value if 'value_ptr' is not
71 * NULL. This also detaches the thread on successful
72 * completion.
73 * NOTE: detached threads cannot be joined or canceled
74 *
75 * RESULTS
76 * 0 'thread' has completed
77 * EINVAL thread is not a joinable thread,
78 * ESRCH no thread could be found with ID 'thread',
79 * ENOENT thread couldn't find it's own valid handle,
80 * EDEADLK attempt to join thread with self
81 *
82 * ------------------------------------------------------
83 */
84 {
85 int result;
86 pthread_t self;
87 ptw32_thread_t * tp = (ptw32_thread_t *) thread.p;
88 ptw32_mcs_local_node_t node;
89
90 ptw32_mcs_lock_acquire(&ptw32_thread_reuse_lock, &node);
91
92 if (NULL == tp
93 || thread.x != tp->ptHandle.x)
94 {
95 result = ESRCH;
96 }
97 else if (PTHREAD_CREATE_DETACHED == tp->detachState)
98 {
99 result = EINVAL;
100 }
101 else
102 {
103 result = 0;
104 }
105
106 ptw32_mcs_lock_release(&node);
107
108 if (result == 0)
109 {
110 /*
111 * The target thread is joinable and can't be reused before we join it.
112 */
113 self = pthread_self();
114
115 if (NULL == self.p)
116 {
117 result = ENOENT;
118 }
119 else if (pthread_equal (self, thread))
120 {
121 result = EDEADLK;
122 }
123 else
124 {
125 /*
126 * Pthread_join is a cancelation point.
127 * If we are canceled then our target thread must not be
128 * detached (destroyed). This is guarranteed because
129 * pthreadCancelableWait will not return if we
130 * are canceled.
131 */
132 result = pthreadCancelableWait (tp->threadH);
133
134 if (0 == result)
135 {
136 if (value_ptr != NULL)
137 {
138 *value_ptr = tp->exitStatus;
139 }
140
141 /*
142 * The result of making multiple simultaneous calls to
143 * pthread_join() or pthread_detach() specifying the same
144 * target is undefined.
145 */
146 result = pthread_detach (thread);
147 }
148 else
149 {
150 result = ESRCH;
151 }
152 }
153 }
154
155 return (result);
156
157 } /* pthread_join */
158