lock.c revision 169695 
1/* Copyright (C) 2005 Free Software Foundation, Inc.
2   Contributed by Richard Henderson <rth@redhat.com>.
3
4   This file is part of the GNU OpenMP Library (libgomp).
5
6   Libgomp is free software; you can redistribute it and/or modify it
7   under the terms of the GNU Lesser General Public License as published by
8   the Free Software Foundation; either version 2.1 of the License, or
9   (at your option) any later version.
10
11   Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
12   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
13   FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
14   more details.
15
16   You should have received a copy of the GNU Lesser General Public License
17   along with libgomp; see the file COPYING.LIB.  If not, write to the
18   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
19   MA 02110-1301, USA.  */
20
21/* As a special exception, if you link this library with other files, some
22   of which are compiled with GCC, to produce an executable, this library
23   does not by itself cause the resulting executable to be covered by the
24   GNU General Public License.  This exception does not however invalidate
25   any other reasons why the executable file might be covered by the GNU
26   General Public License.  */
27
28/* This is the default PTHREADS implementation of the public OpenMP
29   locking primitives.
30
31   Because OpenMP uses different entry points for normal and recursive
32   locks, and pthreads uses only one entry point, a system may be able
33   to do better and streamline the locking as well as reduce the size
34   of the types exported.  */
35
36/* We need Unix98 extensions to get recursive locks.  */
37#define _XOPEN_SOURCE 500
38
39#include "libgomp.h"
40
41
42void
43omp_init_lock (omp_lock_t *lock)
44{
45  pthread_mutex_init (lock, NULL);
46}
47
48void
49omp_destroy_lock (omp_lock_t *lock)
50{
51  pthread_mutex_destroy (lock);
52}
53
54void
55omp_set_lock (omp_lock_t *lock)
56{
57  pthread_mutex_lock (lock);
58}
59
60void
61omp_unset_lock (omp_lock_t *lock)
62{
63  pthread_mutex_unlock (lock);
64}
65
66int
67omp_test_lock (omp_lock_t *lock)
68{
69  return pthread_mutex_trylock (lock) == 0;
70}
71
72void
73omp_init_nest_lock (omp_nest_lock_t *lock)
74{
75  pthread_mutexattr_t attr;
76
77  pthread_mutexattr_init (&attr);
78  pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
79  pthread_mutex_init (&lock->lock, &attr);
80  lock->count = 0;
81  pthread_mutexattr_destroy (&attr);
82}
83
84void
85omp_destroy_nest_lock (omp_nest_lock_t *lock)
86{
87  pthread_mutex_destroy (&lock->lock);
88}
89
90void
91omp_set_nest_lock (omp_nest_lock_t *lock)
92{
93  pthread_mutex_lock (&lock->lock);
94  lock->count++;
95}
96
97void
98omp_unset_nest_lock (omp_nest_lock_t *lock)
99{
100  lock->count--;
101  pthread_mutex_unlock (&lock->lock);
102}
103
104int
105omp_test_nest_lock (omp_nest_lock_t *lock)
106{
107  if (pthread_mutex_trylock (&lock->lock) == 0)
108    return ++lock->count;
109  return 0;
110}
111
112ialias (omp_init_lock)
113ialias (omp_init_nest_lock)
114ialias (omp_destroy_lock)
115ialias (omp_destroy_nest_lock)
116ialias (omp_set_lock)
117ialias (omp_set_nest_lock)
118ialias (omp_unset_lock)
119ialias (omp_unset_nest_lock)
120ialias (omp_test_lock)
121ialias (omp_test_nest_lock)
122