ppapi/shared_impl/ppb_audio_shared.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ppapi/shared_impl/ppb_audio_shared.h"
   6
   7 #include "base/logging.h"
   8 #include "ppapi/shared_impl/ppapi_globals.h"
   9 #include "ppapi/shared_impl/ppb_audio_config_shared.h"
  10 #include "ppapi/shared_impl/proxy_lock.h"
  11
  12 namespace ppapi {
  13
  14 #if defined(OS_NACL)
  15 namespace {
  16 // Because this is static, the function pointers will be NULL initially.
  17 PP_ThreadFunctions thread_functions;
  18 }
  19 #endif  // defined(OS_NACL)
  20
  21 AudioCallbackCombined::AudioCallbackCombined()
  22     : callback_1_0_(NULL), callback_(NULL) {}
  23
  24 AudioCallbackCombined::AudioCallbackCombined(
  25     PPB_Audio_Callback_1_0 callback_1_0)
  26     : callback_1_0_(callback_1_0), callback_(NULL) {}
  27
  28 AudioCallbackCombined::AudioCallbackCombined(PPB_Audio_Callback callback)
  29     : callback_1_0_(NULL), callback_(callback) {}
  30
  31 AudioCallbackCombined::~AudioCallbackCombined() {}
  32
  33 bool AudioCallbackCombined::IsValid() const {
  34   return callback_1_0_ || callback_;
  35 }
  36
  37 void AudioCallbackCombined::Run(void* sample_buffer,
  38                                 uint32_t buffer_size_in_bytes,
  39                                 PP_TimeDelta latency,
  40                                 void* user_data) const {
  41   if (callback_) {
  42     callback_(sample_buffer, buffer_size_in_bytes, latency, user_data);
  43   } else if (callback_1_0_) {
  44     callback_1_0_(sample_buffer, buffer_size_in_bytes, user_data);
  45   } else {
  46     NOTREACHED();
  47   }
  48 }
  49
  50 PPB_Audio_Shared::PPB_Audio_Shared()
  51     : playing_(false),
  52       shared_memory_size_(0),
  53 #if defined(OS_NACL)
  54       thread_id_(0),
  55       thread_active_(false),
  56 #endif
  57       user_data_(NULL),
  58       client_buffer_size_bytes_(0),
  59       bytes_per_second_(0),
  60       buffer_index_(0) {
  61 }
  62
  63 PPB_Audio_Shared::~PPB_Audio_Shared() {
  64   // Shut down the socket to escape any hanging |Receive|s.
  65   if (socket_.get())
  66     socket_->Shutdown();
  67   StopThread();
  68 }
  69
  70 void PPB_Audio_Shared::SetCallback(const AudioCallbackCombined& callback,
  71                                    void* user_data) {
  72   callback_ = callback;
  73   user_data_ = user_data;
  74 }
  75
  76 void PPB_Audio_Shared::SetStartPlaybackState() {
  77   DCHECK(!playing_);
  78 #if !defined(OS_NACL)
  79   DCHECK(!audio_thread_.get());
  80 #else
  81   DCHECK(!thread_active_);
  82 #endif
  83   // If the socket doesn't exist, that means that the plugin has started before
  84   // the browser has had a chance to create all the shared memory info and
  85   // notify us. This is a common case. In this case, we just set the playing_
  86   // flag and the playback will automatically start when that data is available
  87   // in SetStreamInfo.
  88   playing_ = true;
  89   StartThread();
  90 }
  91
  92 void PPB_Audio_Shared::SetStopPlaybackState() {
  93   DCHECK(playing_);
  94   StopThread();
  95   playing_ = false;
  96 }
  97
  98 void PPB_Audio_Shared::SetStreamInfo(
  99     PP_Instance instance,
 100     base::SharedMemoryHandle shared_memory_handle,
 101     size_t shared_memory_size,
 102     base::SyncSocket::Handle socket_handle,
 103     PP_AudioSampleRate sample_rate,
 104     int sample_frame_count) {
 105   socket_.reset(new base::CancelableSyncSocket(socket_handle));
 106   shared_memory_.reset(new base::SharedMemory(shared_memory_handle, false));
 107   shared_memory_size_ = shared_memory_size;
 108   bytes_per_second_ =
 109       kAudioOutputChannels * (kBitsPerAudioOutputSample / 8) * sample_rate;
 110   buffer_index_ = 0;
 111
 112   if (!shared_memory_->Map(shared_memory_size_)) {
 113     PpapiGlobals::Get()->LogWithSource(
 114         instance,
 115         PP_LOGLEVEL_WARNING,
 116         std::string(),
 117         "Failed to map shared memory for PPB_Audio_Shared.");
 118   } else {
 119     audio_bus_ = media::AudioBus::WrapMemory(
 120         kAudioOutputChannels, sample_frame_count, shared_memory_->memory());
 121     // Setup integer audio buffer for user audio data.
 122     client_buffer_size_bytes_ = audio_bus_->frames() * audio_bus_->channels() *
 123                                 kBitsPerAudioOutputSample / 8;
 124     client_buffer_.reset(new uint8_t[client_buffer_size_bytes_]);
 125   }
 126
 127   StartThread();
 128 }
 129
 130 void PPB_Audio_Shared::StartThread() {
 131   // Don't start the thread unless all our state is set up correctly.
 132   if (!playing_ || !callback_.IsValid() || !socket_.get() ||
 133       !shared_memory_->memory() || !audio_bus_.get() || !client_buffer_.get() ||
 134       bytes_per_second_ == 0)
 135     return;
 136   // Clear contents of shm buffer before starting audio thread. This will
 137   // prevent a burst of static if for some reason the audio thread doesn't
 138   // start up quickly enough.
 139   memset(shared_memory_->memory(), 0, shared_memory_size_);
 140   memset(client_buffer_.get(), 0, client_buffer_size_bytes_);
 141 #if !defined(OS_NACL)
 142   DCHECK(!audio_thread_.get());
 143   audio_thread_.reset(
 144       new base::DelegateSimpleThread(this, "plugin_audio_thread"));
 145   audio_thread_->Start();
 146 #else
 147   // Use NaCl's special API for IRT code that creates threads that call back
 148   // into user code.
 149   if (!IsThreadFunctionReady())
 150     return;
 151
 152   DCHECK(!thread_active_);
 153   int result = thread_functions.thread_create(&thread_id_, CallRun, this);
 154   DCHECK_EQ(result, 0);
 155   thread_active_ = true;
 156 #endif
 157 }
 158
 159 void PPB_Audio_Shared::StopThread() {
 160 #if !defined(OS_NACL)
 161   if (audio_thread_.get()) {
 162     // In general, the audio thread should not do Pepper calls, but it might
 163     // anyway (for example, our Audio test does CallOnMainThread). If it did
 164     // a pepper call which acquires the lock (most of them do), and we try to
 165     // shut down the thread and Join it while holding the lock, we would
 166     // deadlock. So we give up the lock here so that the thread at least _can_
 167     // make Pepper calls without causing deadlock.
 168     CallWhileUnlocked(base::Bind(&base::DelegateSimpleThread::Join,
 169                                  base::Unretained(audio_thread_.get())));
 170     audio_thread_.reset();
 171   }
 172 #else
 173   if (thread_active_) {
 174     // See comment above about why we unlock here.
 175     int result = CallWhileUnlocked(thread_functions.thread_join, thread_id_);
 176     DCHECK_EQ(0, result);
 177     thread_active_ = false;
 178   }
 179 #endif
 180 }
 181
 182 // static
 183 bool PPB_Audio_Shared::IsThreadFunctionReady() {
 184 #if defined(OS_NACL)
 185   if (thread_functions.thread_create == NULL ||
 186       thread_functions.thread_join == NULL)
 187     return false;
 188 #endif
 189   return true;
 190 }
 191
 192 #if defined(OS_NACL)
 193 // static
 194 void PPB_Audio_Shared::SetThreadFunctions(
 195     const struct PP_ThreadFunctions* functions) {
 196   thread_functions = *functions;
 197 }
 198
 199 // static
 200 void PPB_Audio_Shared::CallRun(void* self) {
 201   PPB_Audio_Shared* audio = static_cast<PPB_Audio_Shared*>(self);
 202   audio->Run();
 203 }
 204 #endif
 205
 206 void PPB_Audio_Shared::Run() {
 207   int pending_data = 0;
 208   while (sizeof(pending_data) ==
 209          socket_->Receive(&pending_data, sizeof(pending_data))) {
 210     // |buffer_index_| must track the number of Receive() calls.  See the Send()
 211     // call below for why this is important.
 212     ++buffer_index_;
 213     if (pending_data < 0)
 214       break;
 215
 216     PP_TimeDelta latency =
 217         static_cast<double>(pending_data) / bytes_per_second_;
 218     callback_.Run(
 219         client_buffer_.get(), client_buffer_size_bytes_, latency, user_data_);
 220
 221     // Deinterleave the audio data into the shared memory as floats.
 222     audio_bus_->FromInterleaved(client_buffer_.get(),
 223                                 audio_bus_->frames(),
 224                                 kBitsPerAudioOutputSample / 8);
 225
 226     // Let the other end know which buffer we just filled.  The buffer index is
 227     // used to ensure the other end is getting the buffer it expects.  For more
 228     // details on how this works see AudioSyncReader::WaitUntilDataIsReady().
 229     size_t bytes_sent = socket_->Send(&buffer_index_, sizeof(buffer_index_));
 230     if (bytes_sent != sizeof(buffer_index_))
 231       break;
 232   }
 233 }
 234
 235 }  // namespace ppapi