git-svn-id: http://webrtc.googlecode.com/svn/trunk@6 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/system_wrappers/source/atomic32_mac.h b/system_wrappers/source/atomic32_mac.h
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+++ b/system_wrappers/source/atomic32_mac.h
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+// Atomic system independant 32-bit signed integer.
+// Mac implementation.
+#ifndef WEBRTC_SYSTEM_WRAPPERS_SOURCE_ATOMIC32_MAC_H_
+#define WEBRTC_SYSTEM_WRAPPERS_SOURCE_ATOMIC32_MAC_H_
+
+#include <stdlib.h>
+#include <libkern/OSAtomic.h>
+
+#include "common_types.h"
+
+namespace webrtc {
+class Atomic32Impl
+{
+public:
+ inline Atomic32Impl(WebRtc_Word32 initialValue);
+ inline ~Atomic32Impl();
+
+ inline WebRtc_Word32 operator++();
+ inline WebRtc_Word32 operator--();
+
+ inline Atomic32Impl& operator=(const Atomic32Impl& rhs);
+ inline Atomic32Impl& operator=(WebRtc_Word32 rhs);
+ inline WebRtc_Word32 operator+=(WebRtc_Word32 rhs);
+ inline WebRtc_Word32 operator-=(WebRtc_Word32 rhs);
+
+ inline bool CompareExchange(WebRtc_Word32 newValue,
+ WebRtc_Word32 compareValue);
+
+ inline WebRtc_Word32 Value() const;
+private:
+ void* _ptrMemory;
+ // Volatile ensures full memory barriers.
+ volatile WebRtc_Word32* _value;
+};
+
+// TODO (hellner) use aligned_malloc instead of doing it manually.
+inline Atomic32Impl::Atomic32Impl(WebRtc_Word32 initialValue)
+ :
+ _ptrMemory(NULL),
+ _value(NULL)
+{ // Align the memory associated with _value on a 32-bit boundary. This is a
+ // requirement for the used Mac APIs to be atomic.
+ // Keep _ptrMemory to be able to reclaim memory.
+ _ptrMemory = malloc(sizeof(WebRtc_Word32)*2);
+ _value = (WebRtc_Word32*) (((uintptr_t)_ptrMemory+3)&(~0x3));
+ *_value = initialValue;
+}
+
+inline Atomic32Impl::~Atomic32Impl()
+{
+ if(_ptrMemory != NULL)
+ {
+ free(_ptrMemory);
+ }
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator++()
+{
+ return OSAtomicIncrement32Barrier(
+ reinterpret_cast<volatile int32_t*>(_value));
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator--()
+{
+ return OSAtomicDecrement32Barrier(
+ reinterpret_cast<volatile int32_t*>(_value));
+}
+
+inline Atomic32Impl& Atomic32Impl::operator=(const Atomic32Impl& rhs)
+{
+ *_value = *rhs._value;
+ return *this;
+}
+
+inline Atomic32Impl& Atomic32Impl::operator=(WebRtc_Word32 rhs)
+{
+ *_value = rhs;
+ return *this;
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator+=(WebRtc_Word32 rhs)
+{
+ return OSAtomicAdd32Barrier(rhs,
+ reinterpret_cast<volatile int32_t*>(_value));
+}
+
+inline WebRtc_Word32 Atomic32Impl::operator-=(WebRtc_Word32 rhs)
+{
+ return OSAtomicAdd32Barrier(-rhs,
+ reinterpret_cast<volatile int32_t*>(_value));
+}
+
+inline bool Atomic32Impl::CompareExchange(WebRtc_Word32 newValue,
+ WebRtc_Word32 compareValue)
+{
+ return OSAtomicCompareAndSwap32Barrier(
+ compareValue,
+ newValue,
+ reinterpret_cast<volatile int32_t*>(_value));
+}
+
+inline WebRtc_Word32 Atomic32Impl::Value() const
+{
+ return *_value;
+}
+} // namespace webrtc
+#endif // WEBRTC_SYSTEM_WRAPPERS_SOURCE_ATOMIC32_MAC_H_