cairo/src/cairo-atomic.c
M Joonas Pihlaja 80990c7f72 [atomic] Use an integer __sync_val_compare_and_swap() for pointer CAS.
Fix an implicit pointer/integer cast in _cairo_atomic_ptr_cmpxchg()
when building with LLVM/clang.

The Intel synchronization primitives __sync_val_compare_and_swap()
are only defined by Intel for types int, long, long long and their
unsigned variants.  This patch uses one of those for
_cairo_atomic_ptr_cmpxchg() instead of relying on a gcc extension of
__sync_val_compare_and_swap() to pointer types.
2009-06-21 17:34:12 +03:00

113 lines
2.8 KiB
C

/* cairo - a vector graphics library with display and print output
*
* Copyright © 2007 Chris Wilson
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* Contributor(s):
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#include "cairoint.h"
#include "cairo-atomic-private.h"
#include "cairo-mutex-private.h"
#ifdef HAS_ATOMIC_OPS
COMPILE_TIME_ASSERT(sizeof(void*) == sizeof(int) ||
sizeof(void*) == sizeof(long) ||
sizeof(void*) == sizeof(long long));
#else
void
_cairo_atomic_int_inc (int *x)
{
CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
*x += 1;
CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
}
cairo_bool_t
_cairo_atomic_int_dec_and_test (int *x)
{
cairo_bool_t ret;
CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
ret = --*x == 0;
CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
return ret;
}
int
_cairo_atomic_int_cmpxchg (int *x, int oldv, int newv)
{
int ret;
CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
ret = *x;
if (ret == oldv)
*x = newv;
CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
return ret;
}
void *
_cairo_atomic_ptr_cmpxchg (void **x, void *oldv, void *newv)
{
void *ret;
CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
ret = *x;
if (ret == oldv)
*x = newv;
CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
return ret;
}
#endif
#ifdef ATOMIC_OP_NEEDS_MEMORY_BARRIER
int
_cairo_atomic_int_get (int *x)
{
int ret;
CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
ret = *x;
CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
return ret;
}
void
_cairo_atomic_int_set (int *x, int value)
{
CAIRO_MUTEX_LOCK (_cairo_atomic_mutex);
*x = value;
CAIRO_MUTEX_UNLOCK (_cairo_atomic_mutex);
}
#endif