ui/events/keycodes/dom/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 <string>
  10
  11 #include "base/basictypes.h"
  12 #include "ui/events/keycodes/dom/dom_key.h"
  13
  14 // For reference, the W3C UI Event spec is located at:
  15 // http://www.w3.org/TR/uievents/
  16
  17 namespace ui {
  18
  19 enum class DomCode;
  20
  21 enum class DomKeyLocation { STANDARD, LEFT, RIGHT, NUMPAD };
  22
  23 // This structure is used to define the keycode mapping table.
  24 // It is defined here because the unittests need access to it.
  25 typedef struct {
  26   // USB keycode:
  27   //  Upper 16-bits: USB Usage Page.
  28   //  Lower 16-bits: USB Usage Id: Assigned ID within this usage page.
  29   uint32_t usb_keycode;
  30
  31   // Contains one of the following:
  32   //  On Linux: XKB scancode
  33   //  On Windows: Windows OEM scancode
  34   //  On Mac: Mac keycode
  35   int native_keycode;
  36
  37   // The UIEvents (aka: DOM4Events) |code| value as defined in:
  38   // http://www.w3.org/TR/DOM-Level-3-Events-code/
  39   const char* code;
  40 } KeycodeMapEntry;
  41
  42 // A class to convert between the current platform's native keycode (scancode)
  43 // and platform-neutral |code| values (as defined in the W3C UI Events
  44 // spec (http://www.w3.org/TR/uievents/).
  45 class KeycodeConverter {
  46  public:
  47   // Return the value that identifies an invalid native keycode.
  48   static int InvalidNativeKeycode();
  49
  50   // Convert a native (Mac/Win/Linux) keycode into a DomCode.
  51   static DomCode NativeKeycodeToDomCode(int native_keycode);
  52
  53   // Convert a DomCode into a native keycode.
  54   static int DomCodeToNativeKeycode(DomCode code);
  55
  56   // Convert a UI Events |code| string value into a DomCode.
  57   static DomCode CodeStringToDomCode(const char* code);
  58
  59   // Convert a DomCode into a UI Events |code| string value.
  60   static const char* DomCodeToCodeString(DomCode dom_code);
  61
  62   // Return the DomKeyLocation of a DomCode. The DomKeyLocation distinguishes
  63   // keys with the same meaning, and therefore the same DomKey or non-located
  64   // KeyboardCode (VKEY), and corresponds to the DOM UI Events
  65   // |KeyboardEvent.location|.
  66   static DomKeyLocation DomCodeToLocation(DomCode dom_code);
  67
  68   // Convert a UI Events |key| string value into a DomKey.
  69   // Accepts a character string containing either
  70   // - a key name from http://www.w3.org/TR/DOM-Level-3-Events-key/, or
  71   // - a single Unicode character (represented in UTF-8).
  72   // Returns DomKey::NONE for other inputs, including |nullptr|.
  73   static DomKey KeyStringToDomKey(const char* key);
  74
  75   // Convert a DomKey into a UI Events |key| string value.
  76   // For an invalid DomKey, returns an empty string.
  77   static std::string DomKeyToKeyString(DomKey dom_key);
  78
  79   // Returns true if the DomKey is a modifier.
  80   static bool IsDomKeyForModifier(DomKey dom_key);
  81
  82   // The following methods relate to USB keycodes.
  83   // Note that USB keycodes are not part of any web standard.
  84   // Please don't use USB keycodes in new code.
  85
  86   // Return the value that identifies an invalid USB keycode.
  87   static uint32_t InvalidUsbKeycode();
  88
  89   // Convert a USB keycode into an equivalent platform native keycode.
  90   static int UsbKeycodeToNativeKeycode(uint32_t usb_keycode);
  91
  92   // Convert a platform native keycode into an equivalent USB keycode.
  93   static uint32_t NativeKeycodeToUsbKeycode(int native_keycode);
  94
  95   // Convert a USB keycode into a DomCode.
  96   static DomCode UsbKeycodeToDomCode(uint32_t usb_keycode);
  97
  98   // Convert a DomCode into a USB keycode.
  99   static uint32_t DomCodeToUsbKeycode(DomCode dom_code);
 100
 101   // Convert a DOM3 Event |code| string into a USB keycode value.
 102   static uint32_t CodeToUsbKeycode(const char* code);
 103
 104   // Static methods to support testing.
 105   static size_t NumKeycodeMapEntriesForTest();
 106   static const KeycodeMapEntry* GetKeycodeMapForTest();
 107   static const char* DomKeyStringForTest(size_t index);
 108
 109  private:
 110   DISALLOW_COPY_AND_ASSIGN(KeycodeConverter);
 111 };
 112
 113 }  // namespace ui
 114
 115 #endif  // UI_EVENTS_KEYCODES_DOM4_KEYCODE_CONVERTER_H_