AudioCodingModule: Add methods for injecting external encoder stacks

webrtc/modules/audio_coding/acm2/audio_coding_module_impl.h

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 31 matching lines @@
   /////////////////////////////////////////
   //   Sender
   //
 
   // Can be called multiple times for Codec, CNG, RED.
   int RegisterSendCodec(const CodecInst& send_codec) override;
 
   void RegisterExternalSendCodec(
       AudioEncoder* external_speech_encoder) override;
 
+  void ModifyEncoder(
+      FunctionView<void(std::unique_ptr<AudioEncoder>*)> modifier) override;
+
   // Get current send codec.
   rtc::Optional<CodecInst> SendCodec() const override;
 
   // Get current send frequency.
   int SendFrequency() const override;
 
   // Sets the bitrate to the specified value in bits/sec. In case the codec does
   // not support the requested value it will choose an appropriate value
   // instead.
   void SetBitRate(int bitrate_bps) override;
@@ skipping 50 matching lines @@
 
   // Initialize receiver, resets codec database etc.
   int InitializeReceiver() override;
 
   // Get current receive frequency.
   int ReceiveFrequency() const override;
 
   // Get current playout frequency.
   int PlayoutFrequency() const override;
 
-  // Register possible receive codecs, can be called multiple times,
-  // for codecs, CNG, DTMF, RED.
   int RegisterReceiveCodec(const CodecInst& receive_codec) override;
+  int RegisterReceiveCodec(
+      const CodecInst& receive_codec,
+      FunctionView<std::unique_ptr<AudioDecoder>()> isac_factory) override;
 
   int RegisterExternalReceiveCodec(int rtp_payload_type,
                                    AudioDecoder* external_decoder,
                                    int sample_rate_hz,
                                    int num_channels,
                                    const std::string& name) override;
 
   // Get current received codec.
   int ReceiveCodec(CodecInst* current_codec) const override;
 
@@ skipping 71 matching lines @@
     // Logs the new value if it is different from the last logged value, or if
     // this is the first call.
     void MaybeLog(int value);
 
    private:
     int last_value_ = 0;
     int first_time_ = true;
     const std::string histogram_name_;
   };
 
+  int RegisterReceiveCodecUnlocked(
+      const CodecInst& codec,
+      FunctionView<std::unique_ptr<AudioDecoder>()> isac_factory)
+      EXCLUSIVE_LOCKS_REQUIRED(acm_crit_sect_);
+
   int Add10MsDataInternal(const AudioFrame& audio_frame, InputData* input_data)
       EXCLUSIVE_LOCKS_REQUIRED(acm_crit_sect_);
   int Encode(const InputData& input_data)
       EXCLUSIVE_LOCKS_REQUIRED(acm_crit_sect_);
 
   int InitializeReceiverSafe() EXCLUSIVE_LOCKS_REQUIRED(acm_crit_sect_);
 
   bool HaveValidEncoder(const char* caller_name) const
       EXCLUSIVE_LOCKS_REQUIRED(acm_crit_sect_);
 
@@ skipping 25 matching lines @@
   AcmReceiver receiver_;  // AcmReceiver has it's own internal lock.
   ChangeLogger bitrate_logger_ GUARDED_BY(acm_crit_sect_);
 
   std::unique_ptr<EncoderFactory> encoder_factory_ GUARDED_BY(acm_crit_sect_);
 
   // Current encoder stack, either obtained from
   // encoder_factory_->rent_a_codec.RentEncoderStack or provided by a call to
   // RegisterEncoder.
   std::unique_ptr<AudioEncoder> encoder_stack_ GUARDED_BY(acm_crit_sect_);
 
+  std::unique_ptr<AudioDecoder> isac_decoder_ GUARDED_BY(acm_crit_sect_);
+
   // This is to keep track of CN instances where we can send DTMFs.
   uint8_t previous_pltype_ GUARDED_BY(acm_crit_sect_);
 
   // Used when payloads are pushed into ACM without any RTP info
   // One example is when pre-encoded bit-stream is pushed from
   // a file.
   // IMPORTANT: this variable is only used in IncomingPayload(), therefore,
   // no lock acquired when interacting with this variable. If it is going to
   // be used in other methods, locks need to be taken.
   std::unique_ptr<WebRtcRTPHeader> aux_rtp_header_;
@@ skipping 10 matching lines @@
   rtc::CriticalSection callback_crit_sect_;
   AudioPacketizationCallback* packetization_callback_
       GUARDED_BY(callback_crit_sect_);
   ACMVADCallback* vad_callback_ GUARDED_BY(callback_crit_sect_);
 };
 
 }  // namespace acm2
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_CODING_ACM2_AUDIO_CODING_MODULE_IMPL_H_