Index: webrtc/base/atomicops.h |
diff --git a/webrtc/base/atomicops.h b/webrtc/base/atomicops.h |
index a863566a670aad0b3d4904f0040c3c20ad845461..4c8ea898d7ff996ece12580689d7e60fc558da8d 100644 |
--- a/webrtc/base/atomicops.h |
+++ b/webrtc/base/atomicops.h |
@@ -20,7 +20,10 @@ |
#include <windows.h> |
#endif // defined(WEBRTC_WIN) |
+#include "webrtc/base/constructormagic.h" |
+ |
namespace rtc { |
+ |
class AtomicOps { |
public: |
#if defined(WEBRTC_WIN) |
@@ -61,8 +64,46 @@ class AtomicOps { |
#endif |
}; |
+// POD struct version of AtomicOps, prevents accidental non-atomic operator |
+// usage (such as ++, -- or =). Functions are static, so that the AtomicInt:: |
+// prefix must be present in the code, clearly labeling the operations as |
+// atomic. |
+struct AtomicInt { |
+ AtomicInt() : AtomicInt(0) {} |
+ explicit AtomicInt(int value) : value_(value) {} |
+ |
+ // Atomically increments |i|, returns the resulting incremented value. |
+ static int Increment(AtomicInt* i) { |
+ return AtomicOps::Increment(&i->value_); |
+ } |
+ // Atomically decrements |i|, returns the resulting decremented value. |
+ static int Decrement(AtomicInt* i) { |
+ return AtomicOps::Decrement(&i->value_); |
+ } |
+ |
+ // Atomically loads |i|. |
+ static int AcquireLoad(const AtomicInt* i) { |
+ return AtomicOps::AcquireLoad(&i->value_); |
+ } |
+ // Atomically stores |value| in |i|. |
+ static void ReleaseStore(AtomicInt* i, int value) { |
+ AtomicOps::ReleaseStore(&i->value_, value); |
+ } |
+ |
+ // Attempts to compare-and-swaps |old_value| for |new_value| in |i| , returns |
+ // |i|'s initial value. If equal to |old_value|, then the CAS succeeded, |
+ // otherwise no operation is performed. |
+ static int CompareAndSwap(AtomicInt* i, int old_value, int new_value) { |
+ return AtomicOps::CompareAndSwap(&i->value_, old_value, new_value); |
+ } |
+ |
+ private: |
+ volatile int value_; |
+ |
+ RTC_DISALLOW_COPY_AND_ASSIGN(AtomicInt); |
+}; |
} |
#endif // WEBRTC_BASE_ATOMICOPS_H_ |