root/content/browser/renderer_host/gamepad_browser_message_filter.cc

DEFINITIONS

1. is_started_
2. OnMessageReceived
3. OnGamepadStartPolling
4. OnGamepadStopPolling

// Copyright (c) 2011 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/browser/renderer_host/gamepad_browser_message_filter.h"

#include "content/browser/gamepad/gamepad_service.h"
#include "content/common/gamepad_messages.h"

namespace content {

GamepadBrowserMessageFilter::GamepadBrowserMessageFilter()
    : BrowserMessageFilter(GamepadMsgStart),
      is_started_(false) {
}

GamepadBrowserMessageFilter::~GamepadBrowserMessageFilter() {
  DCHECK_CURRENTLY_ON(BrowserThread::IO);
  if (is_started_)
    GamepadService::GetInstance()->RemoveConsumer();
}

bool GamepadBrowserMessageFilter::OnMessageReceived(
    const IPC::Message& message,
    bool* message_was_ok) {
  bool handled = true;
  IPC_BEGIN_MESSAGE_MAP_EX(GamepadBrowserMessageFilter,
                           message,
                           *message_was_ok)
    IPC_MESSAGE_HANDLER(GamepadHostMsg_StartPolling, OnGamepadStartPolling)
    IPC_MESSAGE_HANDLER(GamepadHostMsg_StopPolling, OnGamepadStopPolling)
    IPC_MESSAGE_UNHANDLED(handled = false)
  IPC_END_MESSAGE_MAP_EX()
  return handled;
}

void GamepadBrowserMessageFilter::OnGamepadStartPolling(
    base::SharedMemoryHandle* renderer_handle) {
  GamepadService* service = GamepadService::GetInstance();
  if (!is_started_) {
    is_started_ = true;
    service->AddConsumer();
    *renderer_handle = service->GetSharedMemoryHandleForProcess(PeerHandle());
  } else {
    // Currently we only expect the renderer to tell us once to start.
    NOTREACHED();
  }
}

void GamepadBrowserMessageFilter::OnGamepadStopPolling() {
  // TODO(scottmg): Probably get rid of this message. We can't trust it will
  // arrive anyway if the renderer crashes, etc.
  if (is_started_) {
    is_started_ = false;
    GamepadService::GetInstance()->RemoveConsumer();
  } else {
    NOTREACHED();
  }
}

}  // namespace content