cegcc/src/gcc-4.3.2/libgomp/config/posix95/lock.c

   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
  37 void
  38 omp_init_lock (omp_lock_t *lock)
  39 {
  40   pthread_mutex_init (lock, NULL);
  41 }
  42
  43 void
  44 omp_destroy_lock (omp_lock_t *lock)
  45 {
  46   pthread_mutex_destroy (lock);
  47 }
  48
  49 void
  50 omp_set_lock (omp_lock_t *lock)
  51 {
  52   pthread_mutex_lock (lock);
  53 }
  54
  55 void
  56 omp_unset_lock (omp_lock_t *lock)
  57 {
  58   pthread_mutex_unlock (lock);
  59 }
  60
  61 int
  62 omp_test_lock (omp_lock_t *lock)
  63 {
  64   return pthread_mutex_trylock (lock) == 0;
  65 }
  66
  67 void
  68 omp_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
  75 void
  76 omp_destroy_nest_lock (omp_nest_lock_t *lock)
  77 {
  78   pthread_mutex_destroy (&lock->lock);
  79 }
  80
  81 void
  82 omp_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
  95 void
  96 omp_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
 107 int
 108 omp_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
 122 ialias (omp_init_lock)
 123 ialias (omp_init_nest_lock)
 124 ialias (omp_destroy_lock)
 125 ialias (omp_destroy_nest_lock)
 126 ialias (omp_set_lock)
 127 ialias (omp_set_nest_lock)
 128 ialias (omp_unset_lock)
 129 ialias (omp_unset_nest_lock)
 130 ialias (omp_test_lock)
 131 ialias (omp_test_nest_lock)