/*
* 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 RING_BUFFER_H_
#define RING_BUFFER_H_
#include <media/stagefright/foundation/ABase.h>
#include <hardware/sensors.h>
#include <utils/threads.h>
namespace android {
struct RingBuffer {
explicit RingBuffer(size_t size);
~RingBuffer();
ssize_t write(const sensors_event_t *ev, size_t size);
ssize_t read(sensors_event_t *ev, size_t size);
private:
Mutex mLock;
Condition mNotEmptyCondition;
size_t mSize;
sensors_event_t *mData;
size_t mReadPos, mWritePos;
DISALLOW_EVIL_CONSTRUCTORS(RingBuffer);
};
struct LockfreeBuffer {
LockfreeBuffer(void* buf, size_t size);
~LockfreeBuffer();
// support single writer
void write(const sensors_event_t *ev, size_t size);
private:
sensors_event_t *mData;
size_t mSize;
size_t mWritePos;
int32_t mCounter;
DISALLOW_EVIL_CONSTRUCTORS(LockfreeBuffer);
};
} // namespace android
#endif // RING_BUFFER_H_