1 files changed, 178 insertions, 0 deletions
diff --git a/cpp/include/IceUtil/Atomic.h b/cpp/include/IceUtil/Atomic.h
new file mode 100644
index 00000000000..23d2577b404
--- /dev/null
+++ b/cpp/include/IceUtil/Atomic.h
@@ -0,0 +1,178 @@
+// **********************************************************************
+//
+// Copyright (c) 2003-2015 ZeroC, Inc. All rights reserved.
+//
+// This copy of Ice is licensed to you under the terms described in the
+// ICE_LICENSE file included in this distribution.
+//
+// **********************************************************************
+
+#ifndef ICE_UTIL_ATOMIC_H
+#define ICE_UTIL_ATOMIC_H
+
+#if ((defined(ICE_CPP11) && defined(_MSC_VER) && (_MSC_VER > 1600)) || \
+     (defined(ICE_CPP11) && !defined(_MSC_VER)))
+#   define ICE_CPP11_HAS_ATOMIC
+#endif
+
+#if defined(ICE_CPP11_HAS_ATOMIC)
+#   include <atomic>
+#elif defined(ICE_USE_MUTEX_SHARED)
+
+#   include <IceUtil/Mutex.h>
+
+// Using the gcc builtins requires gcc 4.1 or better. For Linux, i386
+// doesn't work. Apple is supported for all architectures. Sun only
+// supports sparc (32 and 64 bit).
+
+#elif ((defined(__GNUC__) && (((__GNUC__* 100) + __GNUC_MINOR__) >= 401)) || __clang__)  &&                         \
+        ((defined(__sun) && (defined(__sparc) || defined(__sparcv9))) || \
+         defined(__APPLE__) || \
+        (defined(__linux) && \
+                (defined(__i486) || defined(__i586) || \
+                 defined(__i686) || defined(__x86_64))))
+
+#   define ICE_HAS_GCC_BUILTINS
+
+#elif defined(_WIN32)
+// Nothing to include
+#else
+// Use a simple mutex
+#   include <IceUtil/Mutex.h>
+#endif
+
+
+namespace IceUtilInternal
+{
+
+#ifdef ICE_CPP11_HAS_ATOMIC
+typedef std::atomic<int> Atomic;
+#else
+
+#if defined(_WIN32)
+//
+// volatile here is required by InterlockedExchangeXXX
+// family functions.
+//
+typedef volatile unsigned int ATOMIC_T;
+#else
+typedef int ATOMIC_T;
+#endif
+
+
+//
+// This is temporary and very partial placeholder for std::atomic,
+// which is not yet widely available.
+//
+class Atomic : public IceUtil::noncopyable
+{
+public:
+    
+    Atomic() :
+        _ref(0)
+    {
+    }
+    
+    Atomic(int desired) :
+        _ref(desired)
+    {
+    }
+    
+    inline int fetch_add(int value)
+    {
+#if defined(_WIN32)
+        return InterlockedExchangeAdd(&_ref, value);
+#elif defined(ICE_HAS_GCC_BUILTINS)
+        return __sync_fetch_and_add(&_ref, value);
+#else
+        IceUtil::Mutex::Lock sync(_mutex);
+        int tmp = _ref;
+        _ref += value;
+        return tmp;
+#endif
+    }
+    
+    inline int fetch_sub(int value)
+    {
+#if defined(_WIN32)
+        return InterlockedExchangeSubtract(&_ref, value);
+#elif defined(ICE_HAS_GCC_BUILTINS)
+        return __sync_fetch_and_sub(&_ref, value);
+#else
+        IceUtil::Mutex::Lock sync(_mutex);
+        ATOMIC_T tmp = _ref;
+        _ref -= value;
+        return tmp;
+#endif
+    }
+    
+    inline int load() const
+    {
+#if defined(_WIN32)
+        return InterlockedExchangeAdd(const_cast<ATOMIC_T*>(&_ref), 0);
+#elif defined(ICE_HAS_GCC_BUILTINS)
+        return __sync_fetch_and_add(const_cast<ATOMIC_T*>(&_ref), 0);
+#else
+        IceUtil::Mutex::Lock sync(_mutex);
+        return _ref;
+#endif
+    }
+    
+    inline int exchange(int value)
+    {
+#if defined(_WIN32)
+        return InterlockedExchange(&_ref, value);
+#elif defined(ICE_HAS_GCC_BUILTINS)
+        __sync_synchronize();
+        return __sync_lock_test_and_set(&_ref, value);
+#else
+        IceUtil::Mutex::Lock sync(_mutex);
+        int tmp = _ref;
+        _ref = value;
+        return _ref;
+#endif
+    }
+    
+    inline int operator++()
+    {
+        return fetch_add(1) + 1;
+    }
+    
+    inline int operator--()
+    {
+        return fetch_sub(1) - 1;
+    }
+    
+    inline int operator++(int)
+    {
+        return fetch_add(1);
+    }
+    
+    inline int operator--(int)
+    {
+        return fetch_sub(1);
+    }
+    
+    inline operator int()
+    {
+        return load();
+    }
+    
+    inline operator int() const
+    {
+        return load();
+    }
+
+private:
+    
+    ATOMIC_T _ref;
+#if !defined(_WIN32) && !defined(ICE_HAS_GCC_BUILTINS)
+    Mutex _mutex;
+#endif
+};
+
+#endif
+
+}
+
+#endif