ppapi: implement PPB_AudioEncoder

content/renderer/pepper/pepper_audio_encoder_host.h

+// Copyright 2015 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.
+
+#ifndef CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_ENCODER_HOST_H_
+#define CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_ENCODER_HOST_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "base/numerics/safe_math.h"
+#include "content/common/content_export.h"
+#include "ppapi/c/pp_codecs.h"
+#include "ppapi/host/host_message_context.h"
+#include "ppapi/host/resource_host.h"
+#include "ppapi/proxy/resource_message_params.h"
+#include "ppapi/proxy/serialized_structs.h"
+#include "ppapi/shared_impl/media_stream_buffer_manager.h"
+
+namespace content {
+
+class RendererPpapiHost;
+
+class CONTENT_EXPORT PepperAudioEncoderHost
+    : public ppapi::host::ResourceHost,
+      public ppapi::MediaStreamBufferManager::Delegate {
+ public:
+  class AudioEncoderImpl;
+
+  PepperAudioEncoderHost(RendererPpapiHost* host,
+                         PP_Instance instance,
+                         PP_Resource resource);
+  ~PepperAudioEncoderHost() override;
+
+ private:
+  // ResourceHost implementation.
+  int32_t OnResourceMessageReceived(
+      const IPC::Message& msg,
+      ppapi::host::HostMessageContext* context) override;
+
+  int32_t OnHostMsgGetSupportedProfiles(
+      ppapi::host::HostMessageContext* context);
+  int32_t OnHostMsgInitialize(
+      ppapi::host::HostMessageContext* context,
+      const ppapi::proxy::PPB_AudioEncodeParameters& parameters);
+  int32_t OnHostMsgGetAudioBuffers(ppapi::host::HostMessageContext* context);
+  int32_t OnHostMsgEncode(ppapi::host::HostMessageContext* context,
+                          int32_t buffer_id);
+  int32_t OnHostMsgRecycleBitstreamBuffer(
+      ppapi::host::HostMessageContext* context,
+      int32_t buffer_id);
+  int32_t OnHostMsgRequestBitrateChange(
+      ppapi::host::HostMessageContext* context,
+      uint32_t bitrate);
+  int32_t OnHostMsgClose(ppapi::host::HostMessageContext* context);
+
+  void GetSupportedProfiles(std::vector<PP_AudioProfileDescription>* profiles);
+  bool IsInitializationValid(
+      const ppapi::proxy::PPB_AudioEncodeParameters& parameters);
+  base::CheckedNumeric<size_t> GetAudioBufferSize();
+  bool AllocateBuffers();
+  bool AllocateAudioBuffers(const base::CheckedNumeric<size_t>& buffer_size);
+  bool AllocateBitstreamBuffers(
+      const base::CheckedNumeric<size_t>& buffer_size);
+  void DoEncode();
+  void BitstreamBufferReady(int32_t audio_buffer_id,
+                            int32_t bitstream_buffer_id,
+                            int32_t size);
+  void NotifyPepperError(int32_t error);
+  void Close();
+
+  // Non-owning pointer.
+  RendererPpapiHost* renderer_ppapi_host_;
+
+  // Whether the encoder has been successfully initialized.
+  bool initialized_;
+
+  // Last error reported by the encoder.
+  // This represents the current error state of the encoder, i.e. PP_OK
+  // normally, or a Pepper error code if the encoder is uninitialized,
+  // has been notified of an encoder error, has encountered some
+  // other unrecoverable error, or has been closed by the plugin.
+  // This field is checked in most message handlers to decide whether
+  // operations should proceed or fail.
+  int32_t encoder_last_error_;
+
+  // Encoder's parameters, only valid if |initialized_| is true.
+  ppapi::proxy::PPB_AudioEncodeParameters encode_parameters_;
+
+  // Manages buffers containing audio samples from the plugin.
+  ppapi::MediaStreamBufferManager audio_buffer_manager_;
+
+  // Manages buffers containing encoded audio from the browser.
+  ppapi::MediaStreamBufferManager bitstream_buffer_manager_;
+
+  // The encoder actually doing the work. This needs to be after
+  // |audio_buffer_manager_| and |bitstream_buffer_manager_| so the encoder
+  // is shutdown before the buffers' memory is freed.
+  scoped_ptr<AudioEncoderImpl> encoder_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperAudioEncoderHost);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_ENCODER_HOST_H_