1/* Copyright (C) 2006 Free Software Foundation, Inc.
2
3   This file is part of the GNU OpenMP Library (libgomp).
4
5   Libgomp is free software; you can redistribute it and/or modify it
6   under the terms of the GNU Lesser General Public License as published by
7   the Free Software Foundation; either version 2.1 of the License, or
8   (at your option) any later version.
9
10   Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
11   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
12   FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for
13   more details.
14
15   You should have received a copy of the GNU Lesser General Public License
16   along with libgomp; see the file COPYING.LIB.  If not, write to the
17   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
18   MA 02110-1301, USA.  */
19
20/* As a special exception, if you link this library with other files, some
21   of which are compiled with GCC, to produce an executable, this library
22   does not by itself cause the resulting executable to be covered by the
23   GNU General Public License.  This exception does not however invalidate
24   any other reasons why the executable file might be covered by the GNU
25   General Public License.  */
26
27/* This is the POSIX95 implementation of the public OpenMP locking primitives.
28
29   Because OpenMP uses different entry points for normal and recursive
30   locks, and pthreads uses only one entry point, a system may be able
31   to do better and streamline the locking as well as reduce the size
32   of the types exported.  */
33
34#include "libgomp.h"
35
36
37void
38omp_init_lock (omp_lock_t *lock)
39{
40  pthread_mutex_init (lock, NULL);
41}
42
43void
44omp_destroy_lock (omp_lock_t *lock)
45{
46  pthread_mutex_destroy (lock);
47}
48
49void
50omp_set_lock (omp_lock_t *lock)
51{
52  pthread_mutex_lock (lock);
53}
54
55void
56omp_unset_lock (omp_lock_t *lock)
57{
58  pthread_mutex_unlock (lock);
59}
60
61int
62omp_test_lock (omp_lock_t *lock)
63{
64  return pthread_mutex_trylock (lock) == 0;
65}
66
67void
68omp_init_nest_lock (omp_nest_lock_t *lock)
69{
70  pthread_mutex_init (&lock->lock, NULL);
71  lock->owner = (pthread_t) 0;
72  lock->count = 0;
73}
74
75void
76omp_destroy_nest_lock (omp_nest_lock_t *lock)
77{
78  pthread_mutex_destroy (&lock->lock);
79}
80
81void
82omp_set_nest_lock (omp_nest_lock_t *lock)
83{
84  pthread_t me = pthread_self ();
85
86  if (lock->owner != me)
87    {
88      pthread_mutex_lock (&lock->lock);
89      lock->owner = me;
90    }
91
92  lock->count++;
93}
94
95void
96omp_unset_nest_lock (omp_nest_lock_t *lock)
97{
98  lock->count--;
99
100  if (lock->count == 0)
101    {
102      lock->owner = (pthread_t) 0;
103      pthread_mutex_unlock (&lock->lock);
104    }
105}
106
107int
108omp_test_nest_lock (omp_nest_lock_t *lock)
109{
110  pthread_t me = pthread_self ();
111
112  if (lock->owner != me)
113    {
114      if (pthread_mutex_trylock (&lock->lock) != 0)
115	return 0;
116      lock->owner = me;
117    }
118
119  return ++lock->count;
120}
121
122ialias (omp_init_lock)
123ialias (omp_init_nest_lock)
124ialias (omp_destroy_lock)
125ialias (omp_destroy_nest_lock)
126ialias (omp_set_lock)
127ialias (omp_set_nest_lock)
128ialias (omp_unset_lock)
129ialias (omp_unset_nest_lock)
130ialias (omp_test_lock)
131ialias (omp_test_nest_lock)
132