Reland 153623004: Remove the unified IO code on the browser

content/browser/renderer_host/media/audio_sync_reader.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/media/audio_sync_reader.h"
 
 #include <algorithm>
 
 #include "base/command_line.h"
 #include "base/memory/shared_memory.h"
 #include "base/metrics/histogram.h"
 #include "content/public/common/content_switches.h"
 #include "media/audio/audio_buffers_state.h"
 #include "media/audio/audio_parameters.h"
 
 using media::AudioBus;
 
 namespace content {
 
 AudioSyncReader::AudioSyncReader(base::SharedMemory* shared_memory,
-                                 const media::AudioParameters& params,
-                                 int input_channels)
+                                 const media::AudioParameters& params)
     : shared_memory_(shared_memory),
-      input_channels_(input_channels),
       mute_audio_(CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kMuteAudio)),
       packet_size_(shared_memory_->requested_size()),
       renderer_callback_count_(0),
       renderer_missed_callback_count_(0),
 #if defined(OS_MACOSX)
       maximum_wait_time_(params.GetBufferDuration() / 2),
 #else
       // TODO(dalecurtis): Investigate if we can reduce this on all platforms.
       maximum_wait_time_(base::TimeDelta::FromMilliseconds(20)),
 #endif
       buffer_index_(0) {
-  int input_memory_size = 0;
-  int output_memory_size = AudioBus::CalculateMemorySize(params);
-  if (input_channels_ > 0) {
-    // The input storage is after the output storage.
-    int frames = params.frames_per_buffer();
-    input_memory_size = AudioBus::CalculateMemorySize(input_channels_, frames);
-    char* input_data =
-        static_cast<char*>(shared_memory_->memory()) + output_memory_size;
-    input_bus_ = AudioBus::WrapMemory(input_channels_, frames, input_data);
-    input_bus_->Zero();
-  }
-  DCHECK_EQ(packet_size_, output_memory_size + input_memory_size);
+  DCHECK_EQ(packet_size_, AudioBus::CalculateMemorySize(params));
   output_bus_ = AudioBus::WrapMemory(params, shared_memory->memory());
   output_bus_->Zero();
 }
 
 AudioSyncReader::~AudioSyncReader() {
   if (!renderer_callback_count_)
     return;
 
   // Recording the percentage of deadline misses gives us a rough overview of
   // how many users might be running into audio glitches.
@@ skipping 13 matching lines @@
 }
 
 void AudioSyncReader::Read(const AudioBus* source, AudioBus* dest) {
   ++renderer_callback_count_;
   if (!WaitUntilDataIsReady()) {
     ++renderer_missed_callback_count_;
     dest->Zero();
     return;
   }
 
-  // Copy optional synchronized live audio input for consumption by renderer
-  // process.
-  if (input_bus_) {
-    if (source)
-      source->CopyTo(input_bus_.get());
-    else
-      input_bus_->Zero();
-  }
-
   if (mute_audio_)
     dest->Zero();
   else
     output_bus_->CopyTo(dest);
 }
 
 void AudioSyncReader::Close() {
   socket_->Close();
 }
 
@@ skipping 68 matching lines @@
                                base::TimeDelta::FromMilliseconds(1),
                                base::TimeDelta::FromMilliseconds(1000),
                                50);
     return false;
   }
 
   return true;
 }
 
 }  // namespace content