1 files changed, 71 insertions, 0 deletions
diff --git a/libs/hwui/utils/RingBuffer.h b/libs/hwui/utils/RingBuffer.h
new file mode 100644
index 0000000..fc9aec0
--- /dev/null
+++ b/libs/hwui/utils/RingBuffer.h
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef RINGBUFFER_H_
+#define RINGBUFFER_H_
+
+#include "utils/Macros.h"
+
+#include <stddef.h>
+
+namespace android {
+namespace uirenderer {
+
+template<class T, size_t SIZE>
+class RingBuffer {
+    PREVENT_COPY_AND_ASSIGN(RingBuffer);
+
+public:
+    RingBuffer() {}
+    ~RingBuffer() {}
+
+    size_t capacity() { return SIZE; }
+    size_t size() { return mCount; }
+
+    T& next() {
+        mHead = (mHead + 1) % SIZE;
+        if (mCount < SIZE) {
+            mCount++;
+        }
+        return mBuffer[mHead];
+    }
+
+    T& front() {
+        return this[0];
+    }
+
+    T& back() {
+        return this[size() - 1];
+    }
+
+    T& operator[](size_t index) {
+        return mBuffer[(mHead + index + 1) % mCount];
+    }
+
+    void clear() {
+        mCount = 0;
+        mHead = -1;
+    }
+
+private:
+    T mBuffer[SIZE];
+    int mHead = -1;
+    size_t mCount = 0;
+};
+
+}; // namespace uirenderer
+}; // namespace android
+
+#endif /* RINGBUFFER_H_ */