blob: 5d2e2b2eb9b744f646705cb2945d58ba4a98433b [file] [log] [blame]
// Copyright (c) 2012 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 <memory>
#include <utility>
#include <vector>
#include "base/callback_forward.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/shared_memory.h"
#include "base/memory/weak_ptr.h"
#include "base/synchronization/lock.h"
#include "base/system_monitor/system_monitor.h"
#include "device/gamepad/gamepad_export.h"
#include "device/gamepad/gamepad_shared_buffer.h"
#include "third_party/WebKit/public/platform/WebGamepads.h"
namespace base {
class SingleThreadTaskRunner;
class Thread;
namespace device {
class GamepadDataFetcher;
class DEVICE_GAMEPAD_EXPORT GamepadConnectionChangeClient {
virtual void OnGamepadConnectionChange(bool connected,
int index,
const blink::WebGamepad& pad) = 0;
class DEVICE_GAMEPAD_EXPORT GamepadProvider
: public base::SystemMonitor::DevicesChangedObserver {
explicit GamepadProvider(
std::unique_ptr<GamepadSharedBuffer> buffer,
GamepadConnectionChangeClient* connection_change_client);
// Manually specifies the data fetcher. Used for testing.
explicit GamepadProvider(
std::unique_ptr<GamepadSharedBuffer> buffer,
GamepadConnectionChangeClient* connection_change_client,
std::unique_ptr<GamepadDataFetcher> fetcher);
~GamepadProvider() override;
// Returns the shared memory handle of the gamepad data duplicated into the
// given process.
base::SharedMemoryHandle GetSharedMemoryHandleForProcess(
base::ProcessHandle renderer_process);
void GetCurrentGamepadData(blink::WebGamepads* data);
// Pause and resume the background polling thread. Can be called from any
// thread.
void Pause();
void Resume();
// Registers the given closure for calling when the user has interacted with
// the device. This callback will only be issued once.
void RegisterForUserGesture(const base::Closure& closure);
// base::SystemMonitor::DevicesChangedObserver implementation.
void OnDevicesChanged(base::SystemMonitor::DeviceType type) override;
void Initialize(std::unique_ptr<GamepadDataFetcher> fetcher);
// Method for setting up the platform-specific data fetcher. Takes ownership
// of |fetcher|.
void DoInitializePollingThread(std::unique_ptr<GamepadDataFetcher> fetcher);
// Method for sending pause hints to the low-level data fetcher. Runs on
// polling_thread_.
void SendPauseHint(bool paused);
// Method for polling a GamepadDataFetcher. Runs on the polling_thread_.
void DoPoll();
void ScheduleDoPoll();
void OnGamepadConnectionChange(bool connected,
int index,
const blink::WebGamepad& pad);
// Checks the gamepad state to see if the user has interacted with it.
void CheckForUserGesture();
enum { kDesiredSamplingIntervalMs = 16 };
// Keeps track of when the background thread is paused. Access to is_paused_
// must be guarded by is_paused_lock_.
base::Lock is_paused_lock_;
bool is_paused_;
// Keep track of when a polling task is schedlued, so as to prevent us from
// accidentally scheduling more than one at any time, when rapidly toggling
// |is_paused_|.
bool have_scheduled_do_poll_;
// Lists all observers registered for user gestures, and the thread which
// to issue the callbacks on. Since we always issue the callback on the
// thread which the registration happened, and this class lives on the I/O
// thread, the message loop proxies will normally just be the I/O thread.
// However, this will be the main thread for unit testing.
base::Lock user_gesture_lock_;
struct ClosureAndThread {
ClosureAndThread(const base::Closure& c,
const scoped_refptr<base::SingleThreadTaskRunner>& m);
ClosureAndThread(const ClosureAndThread& other);
base::Closure closure;
scoped_refptr<base::SingleThreadTaskRunner> task_runner;
typedef std::vector<ClosureAndThread> UserGestureObserverVector;
UserGestureObserverVector user_gesture_observers_;
// Updated based on notification from SystemMonitor when the system devices
// have been updated, and this notification is passed on to the data fetcher
// to enable it to avoid redundant (and possibly expensive) is-connected
// tests. Access to devices_changed_ must be guarded by
// devices_changed_lock_.
base::Lock devices_changed_lock_;
bool devices_changed_;
bool ever_had_user_gesture_;
class PadState {
PadState() { SetDisconnected(); }
bool Match(const blink::WebGamepad& pad) const;
void SetPad(const blink::WebGamepad& pad);
void SetDisconnected();
void AsWebGamepad(blink::WebGamepad* pad);
bool connected() const { return connected_; }
bool connected_;
unsigned axes_length_;
unsigned buttons_length_;
blink::WebUChar id_[blink::WebGamepad::idLengthCap];
blink::WebUChar mapping_[blink::WebGamepad::mappingLengthCap];
// Used to detect connections and disconnections.
std::unique_ptr<PadState[]> pad_states_;
// Only used on the polling thread.
std::unique_ptr<GamepadDataFetcher> data_fetcher_;
base::Lock shared_memory_lock_;
std::unique_ptr<GamepadSharedBuffer> gamepad_shared_buffer_;
// Polling is done on this background thread.
std::unique_ptr<base::Thread> polling_thread_;
GamepadConnectionChangeClient* connection_change_client_;
static GamepadProvider* instance_;
} // namespace device