diff -r 000000000000 -r 6474c204b198 content/media/AudioNodeExternalInputStream.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/media/AudioNodeExternalInputStream.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,101 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef MOZILLA_AUDIONODEEXTERNALINPUTSTREAM_H_
+#define MOZILLA_AUDIONODEEXTERNALINPUTSTREAM_H_
+
+#include "MediaStreamGraph.h"
+#include "AudioNodeStream.h"
+
+// Forward declaration for mResamplerMap
+typedef struct SpeexResamplerState_ SpeexResamplerState;
+
+namespace mozilla {
+
+/**
+ * This is a MediaStream implementation that acts for a Web Audio node but
+ * unlike other AudioNodeStreams, supports any kind of MediaStream as an
+ * input --- handling any number of audio tracks, resampling them from whatever
+ * sample rate they're using, and handling blocking of the input MediaStream.
+ */
+class AudioNodeExternalInputStream : public AudioNodeStream {
+public:
+  AudioNodeExternalInputStream(AudioNodeEngine* aEngine, TrackRate aSampleRate);
+  ~AudioNodeExternalInputStream();
+
+  virtual void ProcessInput(GraphTime aFrom, GraphTime aTo, uint32_t aFlags) MOZ_OVERRIDE;
+
+private:
+  // For storing pointers and data about input tracks, like the last TrackTick which
+  // was read, and the associated speex resampler.
+  struct TrackMapEntry {
+    ~TrackMapEntry();
+
+    /**
+     * Resamples data from all chunks in aIterator and following, using mResampler,
+     * adding the results to mResampledData.
+     */
+    void ResampleInputData(AudioSegment* aSegment);
+    /**
+     * Resamples a set of channel buffers using mResampler, adding the results
+     * to mResampledData.
+     */
+    void ResampleChannels(const nsTArray<const void*>& aBuffers,
+                          uint32_t aInputDuration,
+                          AudioSampleFormat aFormat,
+                          float aVolume);
+
+    // mEndOfConsumedInputTicks is the end of the input ticks that we've consumed.
+    // 0 if we haven't consumed any yet.
+    TrackTicks mEndOfConsumedInputTicks;
+    // mEndOfLastInputIntervalInInputStream is the timestamp for the end of the
+    // previous interval which was unblocked for both the input and output
+    // stream, in the input stream's timeline, or -1 if there wasn't one.
+    StreamTime mEndOfLastInputIntervalInInputStream;
+    // mEndOfLastInputIntervalInOutputStream is the timestamp for the end of the
+    // previous interval which was unblocked for both the input and output
+    // stream, in the output stream's timeline, or -1 if there wasn't one.
+    StreamTime mEndOfLastInputIntervalInOutputStream;
+    /**
+     * Number of samples passed to the resampler so far.
+     */
+    TrackTicks mSamplesPassedToResampler;
+    /**
+     * Resampler being applied to this track.
+     */
+    SpeexResamplerState* mResampler;
+    /**
+     * The track data that has been resampled to the rate of the
+     * AudioNodeExternalInputStream. All data in these chunks is in floats (or null),
+     * and has the number of channels given in mResamplerChannelCount.
+     * mResampledData starts at zero in the stream's output track (so generally
+     * it will consist of null data followed by actual data).
+     */
+    AudioSegment mResampledData;
+    /**
+     * Number of channels used to create mResampler.
+     */
+    uint32_t mResamplerChannelCount;
+    /**
+     * The ID for the track of the input stream this entry is for.
+     */
+    TrackID mTrackID;
+  };
+
+  nsTArray<TrackMapEntry> mTrackMap;
+  // Amount of track data produced so far. A multiple of WEBAUDIO_BLOCK_SIZE.
+  TrackTicks mCurrentOutputPosition;
+
+  /**
+   * Creates a TrackMapEntry for the track, if needed. Returns the index
+   * of the TrackMapEntry or NoIndex if no entry is needed yet.
+   */
+  uint32_t GetTrackMapEntry(const StreamBuffer::Track& aTrack,
+                            GraphTime aFrom);
+};
+
+}
+
+#endif /* MOZILLA_AUDIONODESTREAM_H_ */