Android Webview IPC-based sync compositing

content/renderer/android/synchronous_compositor_filter.cc

Index: content/renderer/android/synchronous_compositor_filter.cc
diff --git a/content/renderer/android/synchronous_compositor_filter.cc b/content/renderer/android/synchronous_compositor_filter.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5c54e9931d6d6d3c1ee0edbb85eaa4636554c0b1
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+++ b/content/renderer/android/synchronous_compositor_filter.cc
@@ -0,0 +1,249 @@
+// 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.
+
+#include "content/renderer/android/synchronous_compositor_filter.h"
+
+#include "base/callback.h"
+#include "base/stl_util.h"
+#include "base/thread_task_runner_handle.h"
+#include "content/common/android/sync_compositor_messages.h"
+#include "content/renderer/android/synchronous_compositor_proxy.h"
+
+namespace content {
+
+SynchronousCompositorFilter::SynchronousCompositorFilter(
+    const scoped_refptr<base::SingleThreadTaskRunner>& compositor_task_runner)
+    : compositor_task_runner_(compositor_task_runner), filter_ready_(false) {
+  DCHECK(compositor_task_runner_);
+}
+
+SynchronousCompositorFilter::~SynchronousCompositorFilter() {}
+
+void SynchronousCompositorFilter::OnFilterAdded(IPC::Sender* sender) {
+  io_task_runner_ = base::ThreadTaskRunnerHandle::Get();
+  sender_ = sender;
+  compositor_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&SynchronousCompositorFilter::FilterReadyyOnCompositorThread,
+                 this));
+}
+
+void SynchronousCompositorFilter::OnFilterRemoved() {
+  sender_ = nullptr;
+}
+
+void SynchronousCompositorFilter::OnChannelClosing() {
+  sender_ = nullptr;
+}
+
+bool SynchronousCompositorFilter::OnMessageReceived(
+    const IPC::Message& message) {
+  DCHECK_EQ(SyncCompositorMsgStart, IPC_MESSAGE_ID_CLASS(message.type()));
+  bool result = compositor_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(
+          &SynchronousCompositorFilter::OnMessageReceivedOnCompositorThread,
+          this, message));
+  if (!result && message.is_sync()) {
+    IPC::Message* reply = IPC::SyncMessage::GenerateReply(&message);
+    reply->set_reply_error();
+    SendOnIOThread(reply);
+  }
+  return result;
+}
+
+bool SynchronousCompositorFilter::GetSupportedMessageClasses(
+    std::vector<uint32_t>* supported_message_classes) const {
+  supported_message_classes->push_back(SyncCompositorMsgStart);
+  return true;
+}
+
+void SynchronousCompositorFilter::OnMessageReceivedOnCompositorThread(
+    const IPC::Message& message) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+
+  auto itr = sync_compositor_map_.find(message.routing_id());
+  if (itr != sync_compositor_map_.end()) {
+    itr->second->OnMessageReceived(message);
+    return;
+  }
+  IPC::Message* reply = IPC::SyncMessage::GenerateReply(&message);
+  reply->set_reply_error();
+  Send(reply);
+}
+
+bool SynchronousCompositorFilter::Send(IPC::Message* message) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(filter_ready_);
+  if (!io_task_runner_->PostTask(
+          FROM_HERE, base::Bind(&SynchronousCompositorFilter::SendOnIOThread,
+                                this, message))) {
+    delete message;
+    DLOG(WARNING) << "IO PostTask failed";
+    return false;
+  }
+  return true;
+}
+
+void SynchronousCompositorFilter::SendOnIOThread(IPC::Message* message) {
+  DCHECK(io_task_runner_->BelongsToCurrentThread());
+  DCHECK(sender_);
+  if (!sender_) {
+    delete message;
+    return;
+  }
+  bool result = sender_->Send(message);
+  if (!result)
+    DLOG(WARNING) << "Failed to send message";
+}
+
+void SynchronousCompositorFilter::FilterReadyyOnCompositorThread() {
+  DCHECK(!filter_ready_);
+  filter_ready_ = true;
+  for (const auto& entry_pair : entry_map_) {
+    CheckIsReady(entry_pair.first);
+  }
+}
+
+void SynchronousCompositorFilter::RegisterOutputSurface(
+    int routing_id,
+    SynchronousCompositorOutputSurface* output_surface) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(output_surface);
+  Entry& entry = entry_map_[routing_id];
+  DCHECK(!entry.output_surface);
+  entry.output_surface = output_surface;
+  CheckIsReady(routing_id);
+}
+
+void SynchronousCompositorFilter::UnregisterOutputSurface(
+    int routing_id,
+    SynchronousCompositorOutputSurface* output_surface) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(output_surface);
+  DCHECK(ContainsKey(entry_map_, routing_id));
+  Entry& entry = entry_map_[routing_id];
+  DCHECK_EQ(output_surface, entry.output_surface);
+
+  if (entry.IsReady())
+    UnregisterObjects(routing_id);
+  entry.output_surface = nullptr;
+  RemoveEntryIfNeeded(routing_id);
+}
+
+void SynchronousCompositorFilter::RegisterBeginFrameSource(
+    int routing_id,
+    SynchronousCompositorExternalBeginFrameSource* begin_frame_source) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(begin_frame_source);
+  Entry& entry = entry_map_[routing_id];
+  DCHECK(!entry.begin_frame_source);
+  entry.begin_frame_source = begin_frame_source;
+  CheckIsReady(routing_id);
+}
+
+void SynchronousCompositorFilter::UnregisterBeginFrameSource(
+    int routing_id,
+    SynchronousCompositorExternalBeginFrameSource* begin_frame_source) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(begin_frame_source);
+  DCHECK(ContainsKey(entry_map_, routing_id));
+  Entry& entry = entry_map_[routing_id];
+  DCHECK_EQ(begin_frame_source, entry.begin_frame_source);
+
+  if (entry.IsReady())
+    UnregisterObjects(routing_id);
+  entry.begin_frame_source = nullptr;
+  RemoveEntryIfNeeded(routing_id);
+}
+
+void SynchronousCompositorFilter::CheckIsReady(int routing_id) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(ContainsKey(entry_map_, routing_id));
+  Entry& entry = entry_map_[routing_id];
+  if (filter_ready_ && entry.IsReady()) {
+    DCHECK(!sync_compositor_map_.contains(routing_id));
+    sync_compositor_map_.add(
+        routing_id,
+        make_scoped_ptr(new SynchronousCompositorProxy(
+            routing_id, this, entry.output_surface, entry.begin_frame_source,
+            entry.synchronous_input_handler_proxy, &input_handler_)));
+  }
+}
+
+void SynchronousCompositorFilter::UnregisterObjects(int routing_id) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(sync_compositor_map_.contains(routing_id));
+  sync_compositor_map_.erase(routing_id);
+}
+
+void SynchronousCompositorFilter::RemoveEntryIfNeeded(int routing_id) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(ContainsKey(entry_map_, routing_id));
+  Entry& entry = entry_map_[routing_id];
+  if (!entry.begin_frame_source && !entry.output_surface &&
+      !entry.synchronous_input_handler_proxy) {
+    entry_map_.erase(routing_id);
+  }
+}
+
+void SynchronousCompositorFilter::SetBoundHandler(const Handler& handler) {
+  compositor_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(
+          &SynchronousCompositorFilter::SetBoundHandlerOnCompositorThread, this,
+          handler));
+}
+
+void SynchronousCompositorFilter::SetBoundHandlerOnCompositorThread(
+    const Handler& handler) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  input_handler_ = handler;
+}
+
+void SynchronousCompositorFilter::DidAddInputHandler(
+    int routing_id,
+    SynchronousInputHandlerProxy* synchronous_input_handler_proxy) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(synchronous_input_handler_proxy);
+  Entry& entry = entry_map_[routing_id];
+  DCHECK(!entry.synchronous_input_handler_proxy);
+  entry.synchronous_input_handler_proxy = synchronous_input_handler_proxy;
+  CheckIsReady(routing_id);
+}
+
+void SynchronousCompositorFilter::DidRemoveInputHandler(int routing_id) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  DCHECK(ContainsKey(entry_map_, routing_id));
+  Entry& entry = entry_map_[routing_id];
+
+  if (entry.IsReady())
+    UnregisterObjects(routing_id);
+  entry.synchronous_input_handler_proxy = nullptr;
+  RemoveEntryIfNeeded(routing_id);
+}
+
+void SynchronousCompositorFilter::DidOverscroll(
+    int routing_id,
+    const DidOverscrollParams& params) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  // TODO(boliu): Implement
+}
+
+void SynchronousCompositorFilter::DidStopFlinging(int routing_id) {
+  DCHECK(compositor_task_runner_->BelongsToCurrentThread());
+  // TODO(boliu): Implement
+}
+
+SynchronousCompositorFilter::Entry::Entry()
+    : begin_frame_source(nullptr),
+      output_surface(nullptr),
+      synchronous_input_handler_proxy(nullptr) {}
+
+bool SynchronousCompositorFilter::Entry::IsReady() {
+  return begin_frame_source && output_surface &&
+         synchronous_input_handler_proxy;
+}
+
+}  // namespace content