Implement support for USB Xbox360 controllers without a driver on Mac.

content/browser/gamepad/xbox_data_fetcher_mac.h

+// Copyright 2013 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.
+
+#ifndef CONTENT_BROWSER_GAMEPAD_XBOX_DATA_FETCHER_MAC_H_
+#define CONTENT_BROWSER_GAMEPAD_XBOX_DATA_FETCHER_MAC_H_
+
+#include <IOKit/IOKitLib.h>
+#include <CoreFoundation/CoreFoundation.h>

[Avi (use Gerrit), 2013/04/23 15:12:38]

abcde...

+
+#include <set>
+
+#include "base/basictypes.h"
+#include "base/mac/scoped_ioobject.h"
+#include "base/memory/scoped_ptr.h"
+
+class XboxController {
+ public:
+  typedef enum {
+    STATUS_MESSAGE_BUTTONS = 0,
+    STATUS_MESSAGE_LED = 1,
+    STATUS_MESSAGE_UNKNOWN = 2,
+
+    // Apparently this message tells you if the rumble pack is disabled in the
+    // controller. If the rumble pack is disabled, vibration control messages
+    // have no effect.
+    STATUS_MESSAGE_RUMBLE = 3,
+  } StatusMessageType;
+
+  // The LEDs are numbered top left, top right, bottom left, bottom right.
+  typedef enum {
+    LED_OFF = 0,
+
+    // 2 quick flashes, then a series of slow flashes (about 1 per second).
+    LED_FLASH = 1,
+
+    // Flash three times then hold the LED on. This is the standard way to tell
+    // the player which player number they are.
+    LED_FLASH_1 = 2,
+    LED_FLASH_2 = 3,
+    LED_FLASH_3 = 4,
+    LED_FLASH_4 = 5,
+
+    // Simply turn on the numbered LED and turn all other LEDs off.
+    LED_HOLD_1 = 6,
+    LED_HOLD_2 = 7,
+    LED_HOLD_3 = 8,
+    LED_HOLD_4 = 9,
+
+    LED_ROTATE = 10,
+
+    LED_FLASH_FAST = 11,
+    LED_FLASH_SLOW = 12, // Flash about once per 3 seconds
+
+    // Flash alternating LEDs for a few seconds, then flash all LEDs about once
+    // per second
+    LED_ALTERNATE_PATTERN = 13,
+
+    // 14 is just another boring flashing speed.
+
+    // Flash all LEDs once then go black.
+    LED_FLASH_ONCE = 15,
+
+    LED_NUM_PATTERNS
+  } LEDPattern;
+
+  struct Data {
+    float buttons[17];
+    float axes[4];
+  };
+
+  class Delegate {
+   public:
+    virtual void XboxControllerGotData(XboxController* controller,
+                                       const Data& data) = 0;
+    virtual void XboxControllerError(XboxController* controller) = 0;
+  };
+
+  XboxController(Delegate* delegate_);
+  virtual ~XboxController();
+
+  bool OpenDevice(io_service_t service);
+
+  void SetLEDPattern(LEDPattern pattern);
+
+  UInt32 location_id() { return location_id_; }
+  int GetVendorId() const;
+  int GetProductId() const;
+
+ private:
+  static void WriteComplete(void* context, IOReturn result, void* arg0);
+  static void GotData(void* context, IOReturn result, void* arg0);
+
+  void ProcessPacket(uint32 length);
+  void QueueRead();
+
+  void IOError();
+
+  // The device itself. Available on MacOS 10.5.4 and up.

[Avi (use Gerrit), 2013/04/23 15:12:38]

The device is available on 10.5.4 up? Or IOUSBDeviceStruct320? I'm not clear on
why you need to call out system version compatibility in this comment and the
one below.

[jeremya, 2013/04/24 00:18:52]

I guess there's not really any need to call it out at all.

+  struct IOUSBDeviceStruct320** device_;
+
+  // InterfaceInterface300 is available from MacOS 10.5 up. We only care about
+  // the interface which can receive commands. The other interfaces (for
+  // the ChatPad and headset) are ignored for now.
+  struct IOUSBInterfaceStruct300** interface_;
+
+  bool device_is_open_;
+  bool interface_is_open_;
+
+  CFRunLoopSourceRef source_;
+
+  // This will be set to the max packet size reported by the interface, which
+  // is 32 bytes. I would have expected USB to do message framing itself, but
+  // somehow we still sometimes (rarely!) get packets off the interface which
+  // aren't correctly framed. The 360 controller frames its packets with a 2
+  // byte header (type, total length) so we can reframe the packet data
+  // ourselves.
+  uint16 read_buffer_size_;
+  scoped_array<uint8> read_buffer_;

[Avi (use Gerrit), 2013/04/23 15:12:38]

You really need to get off scoped_array. scoped_ptr<uint8[]> should work fine.

[jeremya, 2013/04/24 00:18:52]

Done.

+
+  // The pattern that the LEDs on the device are currently displaying, or
+  // LED_NUM_PATTERNS if unknown.
+  LEDPattern led_pattern_;
+
+  UInt32 location_id_;
+
+  Delegate* delegate_;
+
+  DISALLOW_COPY_AND_ASSIGN(XboxController);
+};
+
+class XboxDataFetcher : public XboxController::Delegate {
+ public:
+  class Delegate {
+   public:
+    virtual void XboxDeviceAdd(XboxController* device) = 0;
+    virtual void XboxDeviceRemove(XboxController* device) = 0;
+    virtual void XboxValueChanged(XboxController* device,
+                                  const XboxController::Data& data) = 0;
+  };
+
+  XboxDataFetcher(Delegate* delegate);
+  virtual ~XboxDataFetcher();
+
+  void RegisterForNotifications();
+  void UnregisterFromNotifications();
+
+ private:
+  static void DeviceAdded(void* context, io_iterator_t iterator);
+  static void DeviceRemoved(void* context, io_iterator_t iterator);
+  void AddController(XboxController* controller);
+  void RemoveController(XboxController* controller);
+  void RemoveControllerByLocationID(uint32 id);
+  virtual void XboxControllerGotData(XboxController* controller,
+                                     const XboxController::Data& data) OVERRIDE;
+  virtual void XboxControllerError(XboxController* controller) OVERRIDE;
+
+  Delegate* delegate_;
+
+  std::set<XboxController*> controllers_;
+
+  bool listening_;
+
+  IONotificationPortRef port_;
+  CFRunLoopSourceRef source_;
+  base::mac::ScopedIOObject<io_iterator_t> device_added_iter_;
+  base::mac::ScopedIOObject<io_iterator_t> device_removed_iter_;
+
+  DISALLOW_COPY_AND_ASSIGN(XboxDataFetcher);
+};
+
+#endif  // CONTENT_BROWSER_GAMEPAD_XBOX_DATA_FETCHER_MAC_H_