cairo/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 #ifndef HAS_ATOMIC_OPS
  40 void
  41 _cairo_atomic_int_inc (int *x)
  42 {
  43     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  44     *x += 1;
  45     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  46 }
  47
  48 cairo_bool_t
  49 _cairo_atomic_int_dec_and_test (int *x)
  50 {
  51     cairo_bool_t ret;
  52
  53     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  54     ret = --*x == 0;
  55     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  56
  57     return ret;
  58 }
  59
  60 int
  61 _cairo_atomic_int_cmpxchg (int *x, int oldv, int newv)
  62 {
  63     int ret;
  64
  65     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  66     ret = *x;
  67     if (ret == oldv)
  68         *x = newv;
  69     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  70
  71     return ret;
  72 }
  73
  74 #endif
  75
  76 #ifdef ATOMIC_OP_NEEDS_MEMORY_BARRIER
  77 int
  78 _cairo_atomic_int_get (int *x)
  79 {
  80     int ret;
  81
  82     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  83     ret = *x;
  84     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  85
  86     return ret;
  87 }
  88
  89 void
  90 _cairo_atomic_int_set (int *x, int value)
  91 {
  92     CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
  93     *x = value;
  94     CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
  95 }
  96 #endif