The Tor Browser: media/webrtc/signaling/src/media-conduit/AudioConduit.h@ac0c01689b40 (annotated)

media/webrtc/signaling/src/media-conduit/AudioConduit.h@ac0c01689b40 (annotated)

media/webrtc/signaling/src/media-conduit/AudioConduit.h

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rwxr-xr-x

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* 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 AUDIO_SESSION_H_
 #define AUDIO_SESSION_H_
 #include "mozilla/Attributes.h"
 #include "mozilla/TimeStamp.h"
 #include "nsTArray.h"
 #include "MediaConduitInterface.h"
 #include "MediaEngineWrapper.h"
 // Audio Engine Includes
 #include "webrtc/common_types.h"
 #include "webrtc/voice_engine/include/voe_base.h"
 #include "webrtc/voice_engine/include/voe_volume_control.h"
 #include "webrtc/voice_engine/include/voe_codec.h"
 #include "webrtc/voice_engine/include/voe_file.h"
 #include "webrtc/voice_engine/include/voe_network.h"
 #include "webrtc/voice_engine/include/voe_external_media.h"
 #include "webrtc/voice_engine/include/voe_audio_processing.h"
 #include "webrtc/voice_engine/include/voe_video_sync.h"
 #include "webrtc/voice_engine/include/voe_rtp_rtcp.h"
 //Some WebRTC types for short notations
  using webrtc::VoEBase;
  using webrtc::VoENetwork;
  using webrtc::VoECodec;
  using webrtc::VoEExternalMedia;
  using webrtc::VoEAudioProcessing;
  using webrtc::VoEVideoSync;
  using webrtc::VoERTP_RTCP;
 /** This file hosts several structures identifying different aspects
  * of a RTP Session.
  */
 namespace mozilla {
 // Helper function
 DOMHighResTimeStamp
 NTPtoDOMHighResTimeStamp(uint32_t ntpHigh, uint32_t ntpLow);
 /**
  * Concrete class for Audio session. Hooks up
  *  - media-source and target to external transport
  */
 class WebrtcAudioConduit:public AudioSessionConduit
 	      		            ,public webrtc::Transport
 {
 public:
   //VoiceEngine defined constant for Payload Name Size.
   static const unsigned int CODEC_PLNAME_SIZE;
   /**
    * APIs used by the registered external transport to this Conduit to
    * feed in received RTP Frames to the VoiceEngine for decoding
    */
   virtual MediaConduitErrorCode ReceivedRTPPacket(const void *data, int len);
   /**
    * APIs used by the registered external transport to this Conduit to
    * feed in received RTCP Frames to the VoiceEngine for decoding
    */
   virtual MediaConduitErrorCode ReceivedRTCPPacket(const void *data, int len);
   /**
    * Function to configure send codec for the audio session
    * @param sendSessionConfig: CodecConfiguration
    * @result: On Success, the audio engine is configured with passed in codec for send
    *          On failure, audio engine transmit functionality is disabled.
    * NOTE: This API can be invoked multiple time. Invoking this API may involve restarting
    *        transmission sub-system on the engine.
    */
   virtual MediaConduitErrorCode ConfigureSendMediaCodec(const AudioCodecConfig* codecConfig);
   /**
    * Function to configure list of receive codecs for the audio session
    * @param sendSessionConfig: CodecConfiguration
    * @result: On Success, the audio engine is configured with passed in codec for send
    *          Also the playout is enabled.
    *          On failure, audio engine transmit functionality is disabled.
    * NOTE: This API can be invoked multiple time. Invoking this API may involve restarting
    *        transmission sub-system on the engine.
    */
   virtual MediaConduitErrorCode ConfigureRecvMediaCodecs(
     const std::vector<AudioCodecConfig* >& codecConfigList);
   /**
    * Function to enable the audio level extension
    * @param enabled: enable extension
    */
   virtual MediaConduitErrorCode EnableAudioLevelExtension(bool enabled, uint8_t id);
   /**
    * Register External Transport to this Conduit. RTP and RTCP frames from the VoiceEngine
    * shall be passed to the registered transport for transporting externally.
    */
   virtual MediaConduitErrorCode AttachTransport(mozilla::RefPtr<TransportInterface> aTransport);
   /**
    * Function to deliver externally captured audio sample for encoding and transport
    * @param audioData [in]: Pointer to array containing a frame of audio
    * @param lengthSamples [in]: Length of audio frame in samples in multiple of 10 milliseconds
    *                             Ex: Frame length is 160, 320, 440 for 16, 32, 44 kHz sampling rates
                                     respectively.
                                     audioData[] should be of lengthSamples in size
                                     say, for 16kz sampling rate, audioData[] should contain 160
                                     samples of 16-bits each for a 10m audio frame.
    * @param samplingFreqHz [in]: Frequency/rate of the sampling in Hz ( 16000, 32000 ...)
    * @param capture_delay [in]:  Approx Delay from recording until it is delivered to VoiceEngine
                                  in milliseconds.
    * NOTE: ConfigureSendMediaCodec() SHOULD be called before this function can be invoked
    *       This ensures the inserted audio-samples can be transmitted by the conduit
    *
    */
   virtual MediaConduitErrorCode SendAudioFrame(const int16_t speechData[],
                                                int32_t lengthSamples,
                                                int32_t samplingFreqHz,
                                                int32_t capture_time);
   /**
    * Function to grab a decoded audio-sample from the media engine for rendering
    * / playoutof length 10 milliseconds.
    *
    * @param speechData [in]: Pointer to a array to which a 10ms frame of audio will be copied
    * @param samplingFreqHz [in]: Frequency of the sampling for playback in Hertz (16000, 32000,..)
    * @param capture_delay [in]: Estimated Time between reading of the samples to rendering/playback
    * @param lengthSamples [out]: Will contain length of the audio frame in samples at return.
                                  Ex: A value of 160 implies 160 samples each of 16-bits was copied
                                      into speechData
    * NOTE: This function should be invoked every 10 milliseconds for the best
    *          peformance
    * NOTE: ConfigureRecvMediaCodec() SHOULD be called before this function can be invoked
    *       This ensures the decoded samples are ready for reading and playout is enabled.
    *
    */
    virtual MediaConduitErrorCode GetAudioFrame(int16_t speechData[],
                                               int32_t samplingFreqHz,
                                               int32_t capture_delay,
                                               int& lengthSamples);
   /**
    * Webrtc transport implementation to send and receive RTP packet.
    * AudioConduit registers itself as ExternalTransport to the VoiceEngine
    */
   virtual int SendPacket(int channel, const void *data, int len) ;
   /**
    * Webrtc transport implementation to send and receive RTCP packet.
    * AudioConduit registers itself as ExternalTransport to the VoiceEngine
    */
   virtual int SendRTCPPacket(int channel, const void *data, int len) ;
   WebrtcAudioConduit():
                       mOtherDirection(nullptr),
                       mShutDown(false),
                       mVoiceEngine(nullptr),
                       mTransport(nullptr),
                       mEngineTransmitting(false),
                       mEngineReceiving(false),
                       mChannel(-1),
                       mCurSendCodecConfig(nullptr),
                       mCaptureDelay(150),
 #ifdef MOZILLA_INTERNAL_API
                       mLastTimestamp(0),
 #endif // MOZILLA_INTERNAL_API
                       mSamples(0),
                       mLastSyncLog(0)
   {
   }
   virtual ~WebrtcAudioConduit();
   MediaConduitErrorCode Init(WebrtcAudioConduit *other);
   int GetChannel() { return mChannel; }
   webrtc::VoiceEngine* GetVoiceEngine() { return mVoiceEngine; }
   bool GetLocalSSRC(unsigned int* ssrc);
   bool GetRemoteSSRC(unsigned int* ssrc);
   bool GetAVStats(int32_t* jitterBufferDelayMs,
                   int32_t* playoutBufferDelayMs,
                   int32_t* avSyncOffsetMs);
   bool GetRTPStats(unsigned int* jitterMs, unsigned int* cumulativeLost);
   bool GetRTCPReceiverReport(DOMHighResTimeStamp* timestamp,
                              uint32_t* jitterMs,
                              uint32_t* packetsReceived,
                              uint64_t* bytesReceived,
                              uint32_t *cumulativeLost,
                              int32_t* rttMs);
   bool GetRTCPSenderReport(DOMHighResTimeStamp* timestamp,
                            unsigned int* packetsSent,
                            uint64_t* bytesSent);
 private:
   WebrtcAudioConduit(const WebrtcAudioConduit& other) MOZ_DELETE;
   void operator=(const WebrtcAudioConduit& other) MOZ_DELETE;
   //Local database of currently applied receive codecs
   typedef std::vector<AudioCodecConfig* > RecvCodecList;
   //Function to convert between WebRTC and Conduit codec structures
   bool CodecConfigToWebRTCCodec(const AudioCodecConfig* codecInfo,
                                 webrtc::CodecInst& cinst);
   //Checks if given sampling frequency is supported
   bool IsSamplingFreqSupported(int freq) const;
   //Generate block size in sample lenght for a given sampling frequency
   unsigned int GetNum10msSamplesForFrequency(int samplingFreqHz) const;
   // Function to copy a codec structure to Conduit's database
   bool CopyCodecToDB(const AudioCodecConfig* codecInfo);
   // Functions to verify if the codec passed is already in
   // conduits database
   bool CheckCodecForMatch(const AudioCodecConfig* codecInfo) const;
   bool CheckCodecsForMatch(const AudioCodecConfig* curCodecConfig,
                            const AudioCodecConfig* codecInfo) const;
   //Checks the codec to be applied
   MediaConduitErrorCode ValidateCodecConfig(const AudioCodecConfig* codecInfo, bool send) const;
   //Utility function to dump recv codec database
   void DumpCodecDB() const;
   // The two sides of a send/receive pair of conduits each keep a pointer to the other.
   // The also share a single VoiceEngine and mChannel.  Shutdown must be coordinated
   // carefully to avoid double-freeing or accessing after one frees.
   WebrtcAudioConduit*  mOtherDirection;
   // Other side has shut down our channel and related items already
   bool mShutDown;
   // These are shared by both directions.  They're released by the last
   // conduit to die
   webrtc::VoiceEngine* mVoiceEngine;
   mozilla::RefPtr<TransportInterface> mTransport;
   ScopedCustomReleasePtr<webrtc::VoENetwork>   mPtrVoENetwork;
   ScopedCustomReleasePtr<webrtc::VoEBase>      mPtrVoEBase;
   ScopedCustomReleasePtr<webrtc::VoECodec>     mPtrVoECodec;
   ScopedCustomReleasePtr<webrtc::VoEExternalMedia> mPtrVoEXmedia;
   ScopedCustomReleasePtr<webrtc::VoEAudioProcessing> mPtrVoEProcessing;
   ScopedCustomReleasePtr<webrtc::VoEVideoSync> mPtrVoEVideoSync;
   ScopedCustomReleasePtr<webrtc::VoERTP_RTCP>  mPtrVoERTP_RTCP;
   ScopedCustomReleasePtr<webrtc::VoERTP_RTCP>  mPtrRTP;
   //engine states of our interets
   bool mEngineTransmitting; // If true => VoiceEngine Send-subsystem is up
   bool mEngineReceiving;    // If true => VoiceEngine Receive-subsystem is up
                             // and playout is enabled
   // Keep track of each inserted RTP block and the time it was inserted
   // so we can estimate the clock time for a specific TimeStamp coming out
   // (for when we send data to MediaStreamTracks).  Blocks are aged out as needed.
   struct Processing {
     TimeStamp mTimeStamp;
     uint32_t mRTPTimeStamp; // RTP timestamps received
   };
   nsAutoTArray<Processing,8> mProcessing;
   int mChannel;
   RecvCodecList    mRecvCodecList;
   AudioCodecConfig* mCurSendCodecConfig;
   // Current "capture" delay (really output plus input delay)
   int32_t mCaptureDelay;
 #ifdef MOZILLA_INTERNAL_API
   uint32_t mLastTimestamp;
 #endif // MOZILLA_INTERNAL_API
   uint32_t mSamples;
   uint32_t mLastSyncLog;
 };
 } // end namespace
 #endif

The Tor Browser / annotate

media/webrtc/signaling/src/media-conduit/AudioConduit.h@ac0c01689b40 (annotated)

media/webrtc/signaling/src/media-conduit/AudioConduit.h