Add gamepad data fetcher for Linux

content/browser/gamepad/platform_data_fetcher_linux.h

+// 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.
+
+#ifndef CONTENT_BROWSER_GAMEPAD_DATA_FETCHER_LINUX_H_
+#define CONTENT_BROWSER_GAMEPAD_DATA_FETCHER_LINUX_H_
+
+#include "build/build_config.h"
+
+#include "base/compiler_specific.h"
+#include "content/browser/gamepad/data_fetcher.h"
+#include "content/browser/gamepad/gamepad_standard_mappings_linux.h"
+#include "content/common/gamepad_hardware_buffer.h"
+
+#include <string>

[Ryan Sleevi, 2011/12/17 04:31:14]

random drive-by style nit: #include <string> before the Chromium headers, and
you don't need to treat build_config.h as a special header

Ordering:
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Names_and_Orde...

build_config.h is not special:
http://www.chromium.org/developers/coding-style#TOC-Platform-specific-code
https://groups.google.com/a/chromium.org/group/chromium-dev/browse_frm/thread...

[scottmg, 2011/12/19 19:41:45]

Done.

+extern "C" {
+struct udev;
+struct udev_device;
+struct udev_monitor;
+}
+
+namespace content {
+
+class GamepadPlatformDataFetcherLinux : public GamepadDataFetcher {
+ public:
+  GamepadPlatformDataFetcherLinux();
+  virtual void GetGamepadData(WebKit::WebGamepads* pads,

[Ryan Sleevi, 2011/12/17 04:31:14]

style nit: Declare DTORs before methods

http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Declaration_Order

Also, see the Chromium style guide rules for virtual interfaces
http://www.chromium.org/developers/coding-style#TOC-Code-formatting

When you implement an interface, group those functions in your header file in
one section, clearly labeled as implementing that interface. Be sure to preserve
the order of the virtual base class, and do not add comments or whitespace
between them, as the reader can refer to the virtual base class for more
information. If you have implementation notes, put them in the implementation of
the function in your .cc file.  Use the OVERRIDE specifier (see details below).

     // RenderViewHost::RendererManagement:
     virtual void ShouldClosePage(bool for_cross_site_transition,
                                  bool proceed) OVERRIDE;

[scottmg, 2011/12/19 19:41:45]

Done.

+                              bool devices_changed_hint) OVERRIDE;
+  virtual ~GamepadPlatformDataFetcherLinux() OVERRIDE;
+
+ private:
+  void EnumerateDevices();
+  void RefreshDevice(udev_device* dev);
+  bool IsGamepad(udev_device* dev, size_t& index, std::string& path);
+  void CheckForAddRemoveEvents();
+  void ReadDeviceData(size_t index);
+
+  // libudev-related items, the main context, and the monitoring context to be
+  // notified about changes to device states.
+  udev* udev_;
+  udev_monitor* monitor_;
+  int monitor_fd_;
+
+  // File descriptors for the /dev/input/js* devices. -1 if not in use.
+  int device_fds_[WebKit::WebGamepads::itemsLengthCap];
+
+  // Functions to map from device data to standard layout, if available. May
+  // be null if no mapping is available.
+  GamepadStandardMappingFunction mappers_[WebKit::WebGamepads::itemsLengthCap];
+
+  // Data that's returned to the consumer.
+  WebKit::WebGamepads data_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_GAMEPAD_DATA_FETCHER_LINUX_H_