1010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten/* 2010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * Copyright (C) 2012 The Android Open Source Project 3010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * 4010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * Licensed under the Apache License, Version 2.0 (the "License"); 5010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * you may not use this file except in compliance with the License. 6010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * You may obtain a copy of the License at 7010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * 8010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * http://www.apache.org/licenses/LICENSE-2.0 9010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * 10010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * Unless required by applicable law or agreed to in writing, software 11010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * distributed under the License is distributed on an "AS IS" BASIS, 12010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * See the License for the specific language governing permissions and 14010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten * limitations under the License. 15010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten */ 16010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 17010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten#ifndef ANDROID_AUDIO_PIPE_H 18010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten#define ANDROID_AUDIO_PIPE_H 19010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 20ed99c2b5a99a8bfc163a6ffa0b767c82032b09b5Glenn Kasten#include <audio_utils/fifo.h> 216eb0c0e980c8ccd5c0cddfd0f1875f9501b293c7Steven Moreland#include <media/nbaio/NBAIO.h> 22010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 23010662326b9c43c703725f933e95e0897f8a6bddGlenn Kastennamespace android { 24010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 25010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten// Pipe is multi-thread safe for readers (see PipeReader), but safe for only a single writer thread. 26010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten// It cannot UNDERRUN on write, unless we allow designation of a master reader that provides the 27010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten// time-base. Readers can be added and removed dynamically, and it's OK to have no readers. 28010662326b9c43c703725f933e95e0897f8a6bddGlenn Kastenclass Pipe : public NBAIO_Sink { 29010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 30010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten friend class PipeReader; 31010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 32010662326b9c43c703725f933e95e0897f8a6bddGlenn Kastenpublic: 33010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // maxFrames will be rounded up to a power of 2, and all slots are available. Must be >= 2. 34c26d923712a59e669d18191d93fbe3696789d592Glenn Kasten // buffer is an optional parameter specifying the virtual address of the pipe buffer, 35c26d923712a59e669d18191d93fbe3696789d592Glenn Kasten // which must be of size roundup(maxFrames) * Format_frameSize(format) bytes. 36c26d923712a59e669d18191d93fbe3696789d592Glenn Kasten Pipe(size_t maxFrames, const NBAIO_Format& format, void *buffer = NULL); 37c26d923712a59e669d18191d93fbe3696789d592Glenn Kasten 38c26d923712a59e669d18191d93fbe3696789d592Glenn Kasten // If a buffer was specified in the constructor, it is not automatically freed by destructor. 39010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten virtual ~Pipe(); 40010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 41010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // NBAIO_Port interface 42010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 43010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten //virtual ssize_t negotiate(const NBAIO_Format offers[], size_t numOffers, 44010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // NBAIO_Format counterOffers[], size_t& numCounterOffers); 45010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten //virtual NBAIO_Format format() const; 46010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 47010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // NBAIO_Sink interface 48010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 49818e7a32ce3633980138aff2c2bfcc5158b3cfccAndy Hung //virtual int64_t framesWritten() const; 50818e7a32ce3633980138aff2c2bfcc5158b3cfccAndy Hung //virtual int64_t framesUnderrun() const; 51818e7a32ce3633980138aff2c2bfcc5158b3cfccAndy Hung //virtual int64_t underruns() const; 52010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 53010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // The write side of a pipe permits overruns; flow control is the caller's responsibility. 54010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten // It doesn't return +infinity because that would guarantee an overrun. 55ed99c2b5a99a8bfc163a6ffa0b767c82032b09b5Glenn Kasten virtual ssize_t availableToWrite() { return mMaxFrames; } 56010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 57010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten virtual ssize_t write(const void *buffer, size_t count); 58010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten //virtual ssize_t writeVia(writeVia_t via, size_t total, void *user, size_t block); 59010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 60010662326b9c43c703725f933e95e0897f8a6bddGlenn Kastenprivate: 61010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten const size_t mMaxFrames; // always a power of 2 62010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten void * const mBuffer; 63ed99c2b5a99a8bfc163a6ffa0b767c82032b09b5Glenn Kasten audio_utils_fifo mFifo; 64ed99c2b5a99a8bfc163a6ffa0b767c82032b09b5Glenn Kasten audio_utils_fifo_writer mFifoWriter; 65010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten volatile int32_t mReaders; // number of PipeReader clients currently attached to this Pipe 66c26d923712a59e669d18191d93fbe3696789d592Glenn Kasten const bool mFreeBufferInDestructor; 67010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten}; 68010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 69010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten} // namespace android 70010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten 71010662326b9c43c703725f933e95e0897f8a6bddGlenn Kasten#endif // ANDROID_AUDIO_PIPE_H 72