/[pcsx2_0.9.7]/trunk/3rdparty/w32pthreads/sem_post.c
ViewVC logotype

Contents of /trunk/3rdparty/w32pthreads/sem_post.c

Parent Directory Parent Directory | Revision Log Revision Log


Revision 10 - (show annotations) (download)
Mon Sep 6 11:40:06 2010 UTC (9 years, 5 months ago) by william
File MIME type: text/plain
File size: 3698 byte(s)
exported r3113 from ./upstream/trunk
1 /*
2 * -------------------------------------------------------------
3 *
4 * Module: sem_post.c
5 *
6 * Purpose:
7 * Semaphores aren't actually part of the PThreads standard.
8 * They are defined by the POSIX Standard:
9 *
10 * POSIX 1003.1b-1993 (POSIX.1b)
11 *
12 * -------------------------------------------------------------
13 *
14 * --------------------------------------------------------------------------
15 *
16 * Pthreads-win32 - POSIX Threads Library for Win32
17 * Copyright(C) 1998 John E. Bossom
18 * Copyright(C) 1999,2005 Pthreads-win32 contributors
19 *
20 * Contact Email: rpj@callisto.canberra.edu.au
21 *
22 * The current list of contributors is contained
23 * in the file CONTRIBUTORS included with the source
24 * code distribution. The list can also be seen at the
25 * following World Wide Web location:
26 * http://sources.redhat.com/pthreads-win32/contributors.html
27 *
28 * This library is free software; you can redistribute it and/or
29 * modify it under the terms of the GNU Lesser General Public
30 * License as published by the Free Software Foundation; either
31 * version 2 of the License, or (at your option) any later version.
32 *
33 * This library is distributed in the hope that it will be useful,
34 * but WITHOUT ANY WARRANTY; without even the implied warranty of
35 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
36 * Lesser General Public License for more details.
37 *
38 * You should have received a copy of the GNU Lesser General Public
39 * License along with this library in the file COPYING.LIB;
40 * if not, write to the Free Software Foundation, Inc.,
41 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
42 */
43
44 #include "ptw32pch.h"
45 #include "semaphore.h"
46
47
48 int
49 sem_post (sem_t * sem)
50 /*
51 * ------------------------------------------------------
52 * DOCPUBLIC
53 * This function posts a wakeup to a semaphore.
54 *
55 * PARAMETERS
56 * sem
57 * pointer to an instance of sem_t
58 *
59 * DESCRIPTION
60 * This function posts a wakeup to a semaphore. If there
61 * are waiting threads (or processes), one is awakened;
62 * otherwise, the semaphore value is incremented by one.
63 *
64 * RESULTS
65 * 0 successfully posted semaphore,
66 * -1 failed, error in errno
67 * ERRNO
68 * EINVAL 'sem' is not a valid semaphore,
69 * ENOSYS semaphores are not supported,
70 * ERANGE semaphore count is too big
71 *
72 * ------------------------------------------------------
73 */
74 {
75 int result = 0;
76 sem_t s = *sem;
77
78 if (s == NULL)
79 {
80 result = EINVAL;
81 }
82 else if ((result = pthread_mutex_lock (&s->lock)) == 0)
83 {
84 /* See sem_destroy.c
85 */
86 if (*sem == NULL)
87 {
88 (void) pthread_mutex_unlock (&s->lock);
89 result = EINVAL;
90 return -1;
91 }
92
93 if (s->value < SEM_VALUE_MAX)
94 {
95 #ifdef NEED_SEM
96 if (++s->value <= 0
97 && !SetEvent(s->sem))
98 {
99 s->value--;
100 result = EINVAL;
101 }
102 #else
103 if (++s->value <= 0
104 && !ReleaseSemaphore (s->sem, 1, NULL))
105 {
106 s->value--;
107 result = EINVAL;
108 }
109 #endif /* NEED_SEM */
110 }
111 else
112 {
113 result = ERANGE;
114 }
115
116 (void) pthread_mutex_unlock (&s->lock);
117 }
118
119 if (result != 0)
120 {
121 errno = result;
122 return -1;
123 }
124
125 return 0;
126
127 } /* sem_post */

  ViewVC Help
Powered by ViewVC 1.1.22