Gamepad API: add support for connection events

content/renderer/gamepad_shared_memory_reader.cc

Index: content/renderer/gamepad_shared_memory_reader.cc
diff --git a/content/renderer/gamepad_shared_memory_reader.cc b/content/renderer/gamepad_shared_memory_reader.cc
index 23edeb3a22368251b5614e58c0ed136c505024e9..2efe4a4d6056669a89b9b304131149f004b9d14a 100644
--- a/content/renderer/gamepad_shared_memory_reader.cc
+++ b/content/renderer/gamepad_shared_memory_reader.cc
@@ -6,7 +6,6 @@
 
 #include "base/debug/trace_event.h"
 #include "base/metrics/histogram.h"
-#include "content/common/gamepad_messages.h"
 #include "content/common/gamepad_user_gesture.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/common/gamepad_hardware_buffer.h"
@@ -14,18 +13,31 @@
 
 namespace content {
 
-GamepadSharedMemoryReader::GamepadSharedMemoryReader()
-    : gamepad_hardware_buffer_(NULL),
+GamepadSharedMemoryReader::GamepadSharedMemoryReader(
+    const scoped_refptr<base::MessageLoopProxy>& io_message_loop)
+    : io_message_loop_(io_message_loop),
+      main_message_loop_(base::MessageLoopProxy::current()),
+      gamepad_hardware_buffer_(NULL),
+      gamepad_listener_(NULL),
+      is_polling_(false),
       ever_interacted_with_(false) {
+}
+
+bool GamepadSharedMemoryReader::EnsurePollingStarted() {
+  if (is_polling_)
+    return true;
+
   CHECK(RenderThread::Get()->Send(new GamepadHostMsg_StartPolling(
       &renderer_shared_memory_handle_)));
+
   // If we don't get a valid handle from the browser, don't try to Map (we're
   // probably out of memory or file handles).
   bool valid_handle = base::SharedMemory::IsHandleValid(
       renderer_shared_memory_handle_);
   UMA_HISTOGRAM_BOOLEAN("Gamepad.ValidSharedMemoryHandle", valid_handle);
   if (!valid_handle)
-    return;
+    return false;
+
   renderer_shared_memory_.reset(
       new base::SharedMemory(renderer_shared_memory_handle_, true));
   CHECK(renderer_shared_memory_->Map(sizeof(GamepadHardwareBuffer)));
@@ -33,9 +45,15 @@ GamepadSharedMemoryReader::GamepadSharedMemoryReader()
   CHECK(memory);
   gamepad_hardware_buffer_ =
       static_cast<GamepadHardwareBuffer*>(memory);
+
+  is_polling_ = true;
+  return true;
 }
 
 void GamepadSharedMemoryReader::SampleGamepads(blink::WebGamepads& gamepads) {
+  if (!EnsurePollingStarted())
+    return;
+
   // ==========
   //   DANGER
   // ==========
@@ -88,8 +106,64 @@ void GamepadSharedMemoryReader::SampleGamepads(blink::WebGamepads& gamepads) {
   }
 }
 
+void GamepadSharedMemoryReader::SetGamepadListener(
+    blink::WebGamepadListener* listener) {
+  gamepad_listener_ = listener;
+}
+
 GamepadSharedMemoryReader::~GamepadSharedMemoryReader() {
   RenderThread::Get()->Send(new GamepadHostMsg_StopPolling());
 }
 
+bool GamepadSharedMemoryReader::OnMessageReceived(const IPC::Message& message) {
+  DCHECK(io_message_loop_->BelongsToCurrentThread());
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(GamepadSharedMemoryReader, message)
+    IPC_MESSAGE_HANDLER(GamepadMsg_GamepadConnected, OnGamepadConnected)
+    IPC_MESSAGE_HANDLER(GamepadMsg_GamepadDisconnected, OnGamepadDisconnected)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void GamepadSharedMemoryReader::OnGamepadConnected(
+    const GamepadConnectionEventMessageParams& params) {
+  int index = params.index;
+  blink::WebGamepad gamepad;
+  params.GetWebGamepad(&gamepad);
+
+  // Dispatch on the main JS thread.
+  main_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&GamepadSharedMemoryReader::DispatchGamepadConnected, this,
+                 index, gamepad));
+}
+
+void GamepadSharedMemoryReader::OnGamepadDisconnected(
+    const GamepadConnectionEventMessageParams& params) {
+  int index = params.index;
+  blink::WebGamepad gamepad;
+  params.GetWebGamepad(&gamepad);
+
+  // Dispatch on the main JS thread.
+  main_message_loop_->PostTask(
+      FROM_HERE,
+      base::Bind(&GamepadSharedMemoryReader::DispatchGamepadDisconnected, this,
+                 index, gamepad));
+}
+
+void GamepadSharedMemoryReader::DispatchGamepadConnected(
+    int index,
+    const blink::WebGamepad& gamepad) {
+  if (gamepad_listener_)
+    gamepad_listener_->onGamepadConnected(index, gamepad);
+}
+
+void GamepadSharedMemoryReader::DispatchGamepadDisconnected(
+    int index,
+    const blink::WebGamepad& gamepad) {
+  if (gamepad_listener_)
+    gamepad_listener_->onGamepadDisconnected(index, gamepad);
+}
+
 } // namespace content