ui/events/keycodes/dom4/keycode_converter.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_EVENTS_KEYCODES_DOM4_KEYCODE_CONVERTER_H_
   6 #define UI_EVENTS_KEYCODES_DOM4_KEYCODE_CONVERTER_H_
   7
   8 #include <stdint.h>
   9 #include "base/basictypes.h"
  10
  11 // For reference, the W3C UI Event spec is located at:
  12 // http://www.w3.org/TR/uievents/
  13
  14 namespace ui {
  15
  16 // This structure is used to define the keycode mapping table.
  17 // It is defined here because the unittests need access to it.
  18 typedef struct {
  19   // USB keycode:
  20   //  Upper 16-bits: USB Usage Page.
  21   //  Lower 16-bits: USB Usage Id: Assigned ID within this usage page.
  22   uint32_t usb_keycode;
  23
  24   // Contains one of the following:
  25   //  On Linux: XKB scancode
  26   //  On Windows: Windows OEM scancode
  27   //  On Mac: Mac keycode
  28   uint16_t native_keycode;
  29
  30   // The UIEvents (aka: DOM4Events) |code| value as defined in:
  31   // https://dvcs.w3.org/hg/d4e/raw-file/tip/source_respec.htm
  32   const char* code;
  33 } KeycodeMapEntry;
  34
  35 // A class to convert between the current platform's native keycode (scancode)
  36 // and platform-neutral |code| values (as defined in the W3C UI Events
  37 // spec (http://www.w3.org/TR/uievents/).
  38 class KeycodeConverter {
  39  public:
  40   // Return the value that identifies an invalid native keycode.
  41   static uint16_t InvalidNativeKeycode();
  42
  43   // Return the string that indentifies an invalid UI Event |code|.
  44   // The returned pointer references a static global string.
  45   static const char* InvalidKeyboardEventCode();
  46
  47   // Convert a native (Mac/Win/Linux) keycode into the |code| string.
  48   // The returned pointer references a static global string.
  49   static const char* NativeKeycodeToCode(uint16_t native_keycode);
  50
  51   // Convert a UI Events |code| string value into a native keycode.
  52   static uint16_t CodeToNativeKeycode(const char* code);
  53
  54   // The following methods relate to USB keycodes.
  55   // Note that USB keycodes are not part of any web standard.
  56   // Please don't use USB keycodes in new code.
  57
  58   // Return the value that identifies an invalid USB keycode.
  59   static uint16_t InvalidUsbKeycode();
  60
  61   // Convert a USB keycode into an equivalent platform native keycode.
  62   static uint16_t UsbKeycodeToNativeKeycode(uint32_t usb_keycode);
  63
  64   // Convert a platform native keycode into an equivalent USB keycode.
  65   static uint32_t NativeKeycodeToUsbKeycode(uint16_t native_keycode);
  66
  67   // Convert a USB keycode into the string with the DOM3 |code| value.
  68   // The returned pointer references a static global string.
  69   static const char* UsbKeycodeToCode(uint32_t usb_keycode);
  70
  71   // Convert a DOM3 Event |code| string into a USB keycode value.
  72   static uint32_t CodeToUsbKeycode(const char* code);
  73
  74   // Static methods to support testing.
  75   static size_t NumKeycodeMapEntriesForTest();
  76   static const KeycodeMapEntry* GetKeycodeMapForTest();
  77
  78  private:
  79   DISALLOW_COPY_AND_ASSIGN(KeycodeConverter);
  80 };
  81
  82 }  // namespace ui
  83
  84 #endif  // UI_EVENTS_KEYCODES_DOM4_KEYCODE_CONVERTER_H_