Support audio output device enumeration and selection in PPAPI

content/renderer/pepper/pepper_audio_output_host.cc

+// Copyright (c) 2017 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/renderer/pepper/pepper_audio_output_host.h"
+
+#include "base/logging.h"
+#include "build/build_config.h"
+#include "content/common/pepper_file_util.h"
+#include "content/renderer/pepper/pepper_audio_controller.h"
+#include "content/renderer/pepper/pepper_media_device_manager.h"
+#include "content/renderer/pepper/pepper_platform_audio_output_dev.h"
+#include "content/renderer/pepper/pepper_plugin_instance_impl.h"
+#include "content/renderer/pepper/plugin_instance_throttler_impl.h"
+#include "content/renderer/pepper/renderer_ppapi_host_impl.h"
+#include "content/renderer/render_frame_impl.h"
+#include "ipc/ipc_message.h"
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/host/dispatch_host_message.h"
+#include "ppapi/host/ppapi_host.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/proxy/serialized_structs.h"
+
+namespace content {
+
+namespace {
+
+base::PlatformFile ConvertSyncSocketHandle(const base::SyncSocket& socket) {
+  return socket.handle();
+}
+
+}  // namespace
+
+PepperAudioOutputHost::PepperAudioOutputHost(RendererPpapiHostImpl* host,
+                                             PP_Instance instance,
+                                             PP_Resource resource)
+    : ResourceHost(host->GetPpapiHost(), instance, resource),
+      renderer_ppapi_host_(host),
+      audio_output_(NULL),
+      playback_throttled_(false),
+      enumeration_helper_(this,
+                          PepperMediaDeviceManager::GetForRenderFrame(
+                              host->GetRenderFrameForInstance(pp_instance())),
+                          PP_DEVICETYPE_DEV_AUDIOOUTPUT,
+                          host->GetDocumentURL(instance)) {
+  PepperPluginInstanceImpl* plugin_instance =
+      static_cast<PepperPluginInstanceImpl*>(
+          PepperPluginInstance::Get(pp_instance()));
+  if (plugin_instance && plugin_instance->throttler())
+    plugin_instance->throttler()->AddObserver(this);
+}
+
+PepperAudioOutputHost::~PepperAudioOutputHost() {
+  PepperPluginInstanceImpl* instance = static_cast<PepperPluginInstanceImpl*>(
+      PepperPluginInstance::Get(pp_instance()));
+  if (instance) {
+    if (instance->throttler()) {
+      instance->throttler()->RemoveObserver(this);
+    }
+    instance->audio_controller().RemoveInstance(this);
+  }
+  Close();
+}
+
+int32_t PepperAudioOutputHost::OnResourceMessageReceived(
+    const IPC::Message& msg,
+    ppapi::host::HostMessageContext* context) {
+  int32_t result = PP_ERROR_FAILED;
+  if (enumeration_helper_.HandleResourceMessage(msg, context, &result))
+    return result;
+
+  PPAPI_BEGIN_MESSAGE_MAP(PepperAudioOutputHost, msg)
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL(PpapiHostMsg_AudioOutput_Open, OnOpen)
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL(PpapiHostMsg_AudioOutput_StartOrStop,
+                                      OnStartOrStop)
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(PpapiHostMsg_AudioOutput_Close, OnClose)
+  PPAPI_END_MESSAGE_MAP()
+  return PP_ERROR_FAILED;
+}
+
+void PepperAudioOutputHost::StreamCreated(
+    base::SharedMemoryHandle shared_memory_handle,
+    size_t shared_memory_size,
+    base::SyncSocket::Handle socket) {
+  OnOpenComplete(PP_OK, shared_memory_handle, shared_memory_size, socket);
+}
+
+void PepperAudioOutputHost::StreamCreationFailed() {
+  OnOpenComplete(PP_ERROR_FAILED, base::SharedMemory::NULLHandle(), 0,
+                 base::SyncSocket::kInvalidHandle);
+}
+
+void PepperAudioOutputHost::SetVolume(double volume) {
+  if (audio_output_)
+    audio_output_->SetVolume(volume);
+}
+
+int32_t PepperAudioOutputHost::OnOpen(ppapi::host::HostMessageContext* context,
+                                      const std::string& device_id,
+                                      PP_AudioSampleRate sample_rate,
+                                      uint32_t sample_frame_count) {
+  if (open_context_.is_valid())
+    return PP_ERROR_INPROGRESS;
+
+  if (audio_output_)
+    return PP_ERROR_FAILED;
+
+  GURL document_url = renderer_ppapi_host_->GetDocumentURL(pp_instance());
+  if (!document_url.is_valid())
+    return PP_ERROR_FAILED;
+
+  // When it is done, we'll get called back on StreamCreated() or
+  // StreamCreationFailed().
+  audio_output_ = PepperPlatformAudioOutputDev::Create(
+      renderer_ppapi_host_->GetRenderFrameForInstance(pp_instance())
+          ->GetRoutingID(),
+      device_id, document_url, static_cast<int>(sample_rate),
+      static_cast<int>(sample_frame_count), this);
+  if (audio_output_) {
+    open_context_ = context->MakeReplyMessageContext();
+    return PP_OK_COMPLETIONPENDING;
+  } else {
+    return PP_ERROR_FAILED;
+  }
+}
+
+int32_t PepperAudioOutputHost::OnStartOrStop(
+    ppapi::host::HostMessageContext* /* context */,
+    bool playback) {
+  if (!audio_output_)
+    return PP_ERROR_FAILED;
+
+  PepperPluginInstanceImpl* instance = static_cast<PepperPluginInstanceImpl*>(
+      PepperPluginInstance::Get(pp_instance()));
+
+  if (playback) {
+    // If plugin is in power saver mode, defer audio IPC communication.
+    if (instance && instance->throttler() &&
+        instance->throttler()->power_saver_enabled()) {
+      instance->throttler()->NotifyAudioThrottled();
+      playback_throttled_ = true;
+      return PP_TRUE;
+    }
+    if (instance)
+      instance->audio_controller().AddInstance(this);
+
+    audio_output_->StartPlayback();
+  } else {
+    if (instance)
+      instance->audio_controller().RemoveInstance(this);
+
+    audio_output_->StopPlayback();
+  }
+  return PP_OK;
+}
+
+int32_t PepperAudioOutputHost::OnClose(
+    ppapi::host::HostMessageContext* /* context */) {
+  Close();
+  return PP_OK;
+}
+
+void PepperAudioOutputHost::OnOpenComplete(
+    int32_t result,
+    base::SharedMemoryHandle shared_memory_handle,
+    size_t shared_memory_size,
+    base::SyncSocket::Handle socket_handle) {
+  // Make sure the handles are cleaned up.
+  base::SyncSocket scoped_socket(socket_handle);
+  base::SharedMemory scoped_shared_memory(shared_memory_handle, false);
+
+  if (!open_context_.is_valid()) {
+    NOTREACHED();
+    return;
+  }
+
+  ppapi::proxy::SerializedHandle serialized_socket_handle(
+      ppapi::proxy::SerializedHandle::SOCKET);
+  ppapi::proxy::SerializedHandle serialized_shared_memory_handle(
+      ppapi::proxy::SerializedHandle::SHARED_MEMORY);
+
+  if (result == PP_OK) {
+    IPC::PlatformFileForTransit temp_socket =
+        IPC::InvalidPlatformFileForTransit();
+    base::SharedMemoryHandle temp_shmem = base::SharedMemory::NULLHandle();
+    result = GetRemoteHandles(scoped_socket, scoped_shared_memory, &temp_socket,
+                              &temp_shmem);
+
+    serialized_socket_handle.set_socket(temp_socket);
+    serialized_shared_memory_handle.set_shmem(temp_shmem, shared_memory_size);
+  }
+
+  // Send all the values, even on error. This simplifies some of our cleanup
+  // code since the handles will be in the other process and could be
+  // inconvenient to clean up. Our IPC code will automatically handle this for
+  // us, as long as the remote side always closes the handles it receives, even
+  // in the failure case.
+  open_context_.params.AppendHandle(serialized_socket_handle);
+  open_context_.params.AppendHandle(serialized_shared_memory_handle);
+  SendOpenReply(result);
+}
+
+int32_t PepperAudioOutputHost::GetRemoteHandles(
+    const base::SyncSocket& socket,
+    const base::SharedMemory& shared_memory,
+    IPC::PlatformFileForTransit* remote_socket_handle,
+    base::SharedMemoryHandle* remote_shared_memory_handle) {
+  *remote_socket_handle = renderer_ppapi_host_->ShareHandleWithRemote(
+      ConvertSyncSocketHandle(socket), false);
+  if (*remote_socket_handle == IPC::InvalidPlatformFileForTransit())
+    return PP_ERROR_FAILED;
+
+  *remote_shared_memory_handle =
+      renderer_ppapi_host_->ShareSharedMemoryHandleWithRemote(
+          shared_memory.handle());
+  if (!base::SharedMemory::IsHandleValid(*remote_shared_memory_handle))
+    return PP_ERROR_FAILED;
+
+  return PP_OK;
+}
+
+void PepperAudioOutputHost::Close() {
+  if (!audio_output_)
+    return;
+
+  audio_output_->ShutDown();
+  audio_output_ = NULL;
+
+  if (open_context_.is_valid())
+    SendOpenReply(PP_ERROR_ABORTED);
+}
+
+void PepperAudioOutputHost::SendOpenReply(int32_t result) {
+  open_context_.params.set_result(result);
+  host()->SendReply(open_context_, PpapiPluginMsg_AudioOutput_OpenReply());
+  open_context_ = ppapi::host::ReplyMessageContext();
+}
+
+void PepperAudioOutputHost::OnThrottleStateChange() {
+  PepperPluginInstanceImpl* instance = static_cast<PepperPluginInstanceImpl*>(
+      PepperPluginInstance::Get(pp_instance()));
+  if (playback_throttled_ && instance && instance->throttler() &&
+      !instance->throttler()->power_saver_enabled()) {
+    // If we have become unthrottled, and we have a pending playback,
+    // start it.
+    StartDeferredPlayback();
+  }
+}
+
+void PepperAudioOutputHost::StartDeferredPlayback() {
+  if (!audio_output_)
+    return;
+
+  DCHECK(playback_throttled_);
+  playback_throttled_ = false;
+
+  PepperPluginInstanceImpl* instance = static_cast<PepperPluginInstanceImpl*>(
+      PepperPluginInstance::Get(pp_instance()));
+  if (instance)
+    instance->audio_controller().AddInstance(this);
+
+  audio_output_->StartPlayback();
+}
+
+}  // namespace content