diff options
Diffstat (limited to 'services/audioflinger/MonoPipe.h')
| -rw-r--r-- | services/audioflinger/MonoPipe.h | 84 |
1 files changed, 0 insertions, 84 deletions
diff --git a/services/audioflinger/MonoPipe.h b/services/audioflinger/MonoPipe.h deleted file mode 100644 index f6e2cb35..00000000 --- a/services/audioflinger/MonoPipe.h +++ /dev/null @@ -1,84 +0,0 @@ -/* - * Copyright (C) 2012 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 ANDROID_AUDIO_MONO_PIPE_H -#define ANDROID_AUDIO_MONO_PIPE_H - -#include <time.h> -#include "NBAIO.h" - -namespace android { - -// MonoPipe is similar to Pipe except: -// - supports only a single reader, called MonoPipeReader -// - write() cannot overrun; instead it will return a short actual count if insufficient space -// - write() can optionally block if the pipe is full -// Like Pipe, it is not multi-thread safe for either writer or reader -// but writer and reader can be different threads. -class MonoPipe : public NBAIO_Sink { - - friend class MonoPipeReader; - -public: - // reqFrames will be rounded up to a power of 2, and all slots are available. Must be >= 2. - // Note: whatever shares this object with another thread needs to do so in an SMP-safe way (like - // creating it the object before creating the other thread, or storing the object with a - // release_store). Otherwise the other thread could see a partially-constructed object. - MonoPipe(size_t reqFrames, NBAIO_Format format, bool writeCanBlock = false); - virtual ~MonoPipe(); - - // NBAIO_Port interface - - //virtual ssize_t negotiate(const NBAIO_Format offers[], size_t numOffers, - // NBAIO_Format counterOffers[], size_t& numCounterOffers); - //virtual NBAIO_Format format() const; - - // NBAIO_Sink interface - - //virtual size_t framesWritten() const; - //virtual size_t framesUnderrun() const; - //virtual size_t underruns() const; - - virtual ssize_t availableToWrite() const; - virtual ssize_t write(const void *buffer, size_t count); - //virtual ssize_t writeVia(writeVia_t via, size_t total, void *user, size_t block); - - // average number of frames present in the pipe under normal conditions. - // See throttling mechanism in MonoPipe::write() - size_t getAvgFrames() const { return mSetpoint; } - void setAvgFrames(size_t setpoint); - size_t maxFrames() const { return mMaxFrames; } - -private: - const size_t mReqFrames; // as requested in constructor, unrounded - const size_t mMaxFrames; // always a power of 2 - void * const mBuffer; - // mFront and mRear will never be separated by more than mMaxFrames. - // 32-bit overflow is possible if the pipe is active for a long time, but if that happens it's - // safe because we "&" with (mMaxFrames-1) at end of computations to calculate a buffer index. - volatile int32_t mFront; // written by reader with android_atomic_release_store, - // read by writer with android_atomic_acquire_load - volatile int32_t mRear; // written by writer with android_atomic_release_store, - // read by reader with android_atomic_acquire_load - bool mWriteTsValid; // whether mWriteTs is valid - struct timespec mWriteTs; // time that the previous write() completed - size_t mSetpoint; // target value for pipe fill depth - const bool mWriteCanBlock; // whether write() should block if the pipe is full -}; - -} // namespace android - -#endif // ANDROID_AUDIO_MONO_PIPE_H |