text: /*
   * Copyright 2019 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 OBOE_AUDIO_SOURCE_CALLER_H
  #define OBOE_AUDIO_SOURCE_CALLER_H
  
  #include "OboeDebug.h"
  #include "oboe/Oboe.h"
  
  #include "flowgraph/FlowGraphNode.h"
  #include "FixedBlockReader.h"
  
  namespace oboe {
  
  class AudioStreamCallback;
  class AudioStream;
  
  /**
   * For output streams that use a callback, call the application for more data.
   * For input streams that do not use a callback, read from the stream.
   */
  class AudioSourceCaller : public flowgraph::FlowGraphSource, public FixedBlockProcessor {
  public:
      AudioSourceCaller(int32_t channelCount, int32_t framesPerCallback, int32_t bytesPerSample)
              : FlowGraphSource(channelCount)
              , mBlockReader(*this) {
          mBlockReader.open(channelCount * framesPerCallback * bytesPerSample);
      }
  
      /**
       * Set the stream to use as a source of data.
       * @param stream
       */
      void setStream(oboe::AudioStream *stream) {
          mStream = stream;
      }
  
      oboe::AudioStream *getStream() {
          return mStream;
      }
  
      /**
       * Timeout value to use when calling audioStream->read().
       * @param timeoutNanos Zero for no timeout or time in nanoseconds.
       */
      void setTimeoutNanos(int64_t timeoutNanos) {
          mTimeoutNanos = timeoutNanos;
      }
  
      int64_t getTimeoutNanos() const {
          return mTimeoutNanos;
      }
  
      /**
       * Called internally for block size adaptation.
       * @param buffer
       * @param numBytes
       * @return
       */
      int32_t onProcessFixedBlock(uint8_t *buffer, int32_t numBytes) override;
  
  protected:
      oboe::AudioStream         *mStream = nullptr;
      int64_t                    mTimeoutNanos = 0;
  
      FixedBlockReader           mBlockReader;
  };
  
  }
  #endif //OBOE_AUDIO_SOURCE_CALLER_H
  