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