[PPAPI] Implement media stream video track API

content/renderer/pepper/pepper_media_stream_track_host_base.cc

+// Copyright (c) 2014 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_media_stream_track_host_base.h"
+
+#include "content/public/renderer/render_thread.h"
+#include "content/public/renderer/renderer_ppapi_host.h"
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/host/dispatch_host_message.h"
+#include "ppapi/host/host_message_context.h"
+#include "ppapi/host/ppapi_host.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/shared_impl/media_stream_frame.h"
+
+using ppapi::host::HostMessageContext;
+using ppapi::proxy::SerializedHandle;
+
+namespace content {
+
+PepperMediaStreamTrackHostBase::PepperMediaStreamTrackHostBase(
+    RendererPpapiHost* host,
+    PP_Instance instance,
+    PP_Resource resource)
+    : ResourceHost(host->GetPpapiHost(), instance, resource),
+      host_(host),
+      frame_buffer_(this) {
+}
+
+PepperMediaStreamTrackHostBase::~PepperMediaStreamTrackHostBase() {
+}
+
+bool PepperMediaStreamTrackHostBase::InitFrames(int32_t number_of_frames,
+                                                int32_t frame_size) {
+  DCHECK_GT(number_of_frames, 0);
+  DCHECK_GT(frame_size,
+            static_cast<int32_t>(sizeof(ppapi::MediaStreamFrame::Header)));
+  // Make each frame 4 byte aligned.
+  frame_size = (frame_size + 3) & ~0x3;
+
+  int32_t size = number_of_frames * frame_size;
+  content::RenderThread* render_thread = content::RenderThread::Get();
+  scoped_ptr<base::SharedMemory> shm(
+      render_thread->HostAllocateSharedMemoryBuffer(size).Pass());
+  if (!shm)
+    return false;
+
+  base::SharedMemoryHandle shm_handle = shm->handle();
+  if (!frame_buffer_.SetFrames(number_of_frames, frame_size, shm.Pass(), true))
+    return false;
+
+  base::PlatformFile platform_file =
+#if defined(OS_WIN)
+    reinterpret_cast<HANDLE>(static_cast<intptr_t>(shm_handle));
+#elif defined(OS_POSIX)
+    shm_handle.fd;
+#else
+#error Not implemented.
+#endif
+  SerializedHandle handle(
+      host_->ShareHandleWithRemote(platform_file, false), size);
+  host()->SendUnsolicitedReplyWithHandles(pp_resource(),
+      PpapiPluginMsg_MediaStreamTrack_InitFrames(number_of_frames, frame_size),
+      std::vector<SerializedHandle>(1, handle));
+  return true;
+}
+
+void PepperMediaStreamTrackHostBase::PluginEnqueueFrame(int32_t index) {
+  DCHECK_GE(index, 0);
+  DCHECK_LT(index, frame_buffer_.number_of_frames());
+  host()->SendUnsolicitedReply(pp_resource(),
+      PpapiPluginMsg_MediaStreamTrack_EnqueueFrame(index));
+}
+
+int32_t PepperMediaStreamTrackHostBase::OnResourceMessageReceived(
+    const IPC::Message& msg,
+    HostMessageContext* context) {
+  IPC_BEGIN_MESSAGE_MAP(PepperMediaStreamTrackHostBase, msg)
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL(
+        PpapiHostMsg_MediaStreamTrack_EnqueueFrame, OnHostMsgEnqueueFrame)
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(
+        PpapiHostMsg_MediaStreamTrack_Close, OnHostMsgClose)
+  IPC_END_MESSAGE_MAP()
+  return ppapi::host::ResourceHost::OnResourceMessageReceived(msg, context);
+}
+
+int32_t PepperMediaStreamTrackHostBase::OnHostMsgEnqueueFrame(
+    HostMessageContext* context,
+    int32_t index) {
+  frame_buffer_.EnqueueFrame(index);
+  return PP_OK;
+}
+
+int32_t PepperMediaStreamTrackHostBase::OnHostMsgClose(
+    HostMessageContext* context) {
+  OnClose();
+  return PP_OK;
+}
+
+}  // namespace content