libgomp/config/posix/ptrlock.h

   1 /* Copyright (C) 2008-2014 Free Software Foundation, Inc.
   2    Contributed by Jakub Jelinek <jakub@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 General Public License as published by
   8    the Free Software Foundation; either version 3, or (at your option)
   9    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 General Public License for
  14    more details.
  15
  16    Under Section 7 of GPL version 3, you are granted additional
  17    permissions described in the GCC Runtime Library Exception, version
  18    3.1, as published by the Free Software Foundation.
  19
  20    You should have received a copy of the GNU General Public License and
  21    a copy of the GCC Runtime Library Exception along with this program;
  22    see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23    <http://www.gnu.org/licenses/>.  */
  24
  25 /* This is a generic POSIX implementation of a mutex synchronization
  26    mechanism for libgomp.  This type is private to the library.  */
  27
  28 #ifndef GOMP_PTRLOCK_H
  29 #define GOMP_PTRLOCK_H 1
  30
  31 typedef struct { void *ptr; gomp_mutex_t lock; } gomp_ptrlock_t;
  32
  33 static inline void gomp_ptrlock_init (gomp_ptrlock_t *ptrlock, void *ptr)
  34 {
  35   ptrlock->ptr = ptr;
  36   gomp_mutex_init (&ptrlock->lock);
  37 }
  38
  39 static inline void *gomp_ptrlock_get (gomp_ptrlock_t *ptrlock)
  40 {
  41   if (ptrlock->ptr != NULL)
  42     return ptrlock->ptr;
  43
  44   gomp_mutex_lock (&ptrlock->lock);
  45   if (ptrlock->ptr != NULL)
  46     {
  47       gomp_mutex_unlock (&ptrlock->lock);
  48       return ptrlock->ptr;
  49     }
  50
  51   return NULL;
  52 }
  53
  54 static inline void gomp_ptrlock_set (gomp_ptrlock_t *ptrlock, void *ptr)
  55 {
  56   ptrlock->ptr = ptr;
  57   gomp_mutex_unlock (&ptrlock->lock);
  58 }
  59
  60 static inline void gomp_ptrlock_destroy (gomp_ptrlock_t *ptrlock)
  61 {
  62   gomp_mutex_destroy (&ptrlock->lock);
  63 }
  64
  65 #endif /* GOMP_PTRLOCK_H */