src/cairo-atomic.c

   1 /* cairo - a vector graphics library with display and print output
   2  *
   3  * Copyright © 2007 Chris Wilson
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it either under the terms of the GNU Lesser General Public
   7  * License version 2.1 as published by the Free Software Foundation
   8  * (the "LGPL") or, at your option, under the terms of the Mozilla
   9  * Public License Version 1.1 (the "MPL"). If you do not alter this
  10  * notice, a recipient may use your version of this file under either
  11  * the MPL or the LGPL.
  12  *
  13  * You should have received a copy of the LGPL along with this library
  14  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
  15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  16  * You should have received a copy of the MPL along with this library
  17  * in the file COPYING-MPL-1.1
  18  *
  19  * The contents of this file are subject to the Mozilla Public License
  20  * Version 1.1 (the "License"); you may not use this file except in
  21  * compliance with the License. You may obtain a copy of the License at
  22  * http://www.mozilla.org/MPL/
  23  *
  24  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
  25  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
  26  * the specific language governing rights and limitations.
  27  *
  28  * The Original Code is the cairo graphics library.
  29  *
  30  * Contributor(s):
  31  *      Chris Wilson <chris@chris-wilson.co.uk>
  32  */
  33
  34 #include "cairoint.h"
  35
  36 #include "cairo-atomic-private.h"
  37 #include "cairo-mutex-private.h"
  38
  39 #ifdef HAS_ATOMIC_OPS
  40 COMPILE_TIME_ASSERT(sizeof(void*) == sizeof(int) ||
  41                     sizeof(void*) == sizeof(long) ||
  42                     sizeof(void*) == sizeof(long long));
  43 #else
  44 void
  45 _cairo_atomic_int_inc (int *x)
  46 {
  47     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  48     *x += 1;
  49     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  50 }
  51
  52 cairo_bool_t
  53 _cairo_atomic_int_dec_and_test (int *x)
  54 {
  55     cairo_bool_t ret;
  56
  57     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  58     ret = --*x == 0;
  59     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  60
  61     return ret;
  62 }
  63
  64 int
  65 _cairo_atomic_int_cmpxchg (int *x, int oldv, int newv)
  66 {
  67     int ret;
  68
  69     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  70     ret = *x;
  71     if (ret == oldv)
  72         *x = newv;
  73     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  74
  75     return ret;
  76 }
  77
  78 void *
  79 _cairo_atomic_ptr_cmpxchg (void **x, void *oldv, void *newv)
  80 {
  81     void *ret;
  82
  83     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  84     ret = *x;
  85     if (ret == oldv)
  86         *x = newv;
  87     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  88
  89     return ret;
  90 }
  91 #endif
  92
  93 #ifdef ATOMIC_OP_NEEDS_MEMORY_BARRIER
  94 int
  95 _cairo_atomic_int_get (int *x)
  96 {
  97     int ret;
  98
  99     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
 100     ret = *x;
 101     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
 102
 103     return ret;
 104 }
 105
 106 void
 107 _cairo_atomic_int_set (int *x, int value)
 108 {
 109     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
 110     *x = value;
 111     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
 112 }
 113 #endif