gecko-dev/dom/gamepad/GamepadPlatformService.h

96 строки
3.3 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_GamepadPlatformService_h_
#define mozilla_dom_GamepadPlatformService_h_
#include "mozilla/dom/GamepadBinding.h"
#include "mozilla/Mutex.h"
#include "mozilla/StaticPtr.h"
namespace mozilla {
namespace dom {
class GamepadEventChannelParent;
// Platform Service for building and transmitting IPDL messages
// through the HAL sandbox. Used by platform specific
// Gamepad implementations
//
// This class can be accessed by the following 2 threads :
// 1. Background thread:
// This thread takes charge of IPDL communications
// between here and DOM side
//
// 2. Monitor Thread:
// This thread is populated in platform-dependent backends, which
// is in charge of processing gamepad hardware events from OS
class GamepadPlatformService final
{
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(GamepadPlatformService)
public:
//Get the singleton service
static already_AddRefed<GamepadPlatformService> GetParentService();
// Add a gamepad to the list of known gamepads, and return its index.
uint32_t AddGamepad(const char* aID, GamepadMappingType aMapping,
uint32_t aNumButtons, uint32_t aNumAxes);
// Remove the gamepad at |aIndex| from the list of known gamepads.
void RemoveGamepad(uint32_t aIndex);
// Update the state of |aButton| for the gamepad at |aIndex| for all
// windows that are listening and visible, and fire one of
// a gamepadbutton{up,down} event at them as well.
// aPressed is used for digital buttons, aValue is for analog buttons.
void NewButtonEvent(uint32_t aIndex, uint32_t aButton, bool aPressed,
double aValue);
// When only a digital button is available the value will be synthesized.
void NewButtonEvent(uint32_t aIndex, uint32_t aButton, bool aPressed);
// Update the state of |aAxis| for the gamepad at |aIndex| for all
// windows that are listening and visible, and fire a gamepadaxismove
// event at them as well.
void NewAxisMoveEvent(uint32_t aIndex, uint32_t aAxis, double aValue);
// When shutting down the platform communications for gamepad, also reset the
// indexes.
void ResetGamepadIndexes();
//Add IPDL parent instance
void AddChannelParent(GamepadEventChannelParent* aParent);
//Remove IPDL parent instance
void RemoveChannelParent(GamepadEventChannelParent* aParent);
bool HasGamepadListeners();
void MaybeShutdown();
private:
GamepadPlatformService();
~GamepadPlatformService();
template<class T> void NotifyGamepadChange(const T& aInfo);
void Cleanup();
// mGamepadIndex can only be accessed by monitor thread
uint32_t mGamepadIndex;
// mChannelParents stores all the GamepadEventChannelParent instances
// which may be accessed by both background thread and monitor thread
// simultaneously, so we have a mutex to prevent race condition
nsTArray<RefPtr<GamepadEventChannelParent>> mChannelParents;
// This mutex protects mChannelParents from race condition
// between background and monitor thread
Mutex mMutex;
};
} // namespace dom
} // namespace mozilla
#endif