ui/events/ozone/layout/xkb/xkb_keyboard_layout_engine.h

   1 // Copyright 2014 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_OZONE_LAYOUT_XKB_XKB_KEYBOARD_LAYOUT_ENGINE_H_
   6 #define UI_EVENTS_OZONE_LAYOUT_XKB_XKB_KEYBOARD_LAYOUT_ENGINE_H_
   7
   8 #include <xkbcommon/xkbcommon.h>
   9
  10 #include "base/containers/hash_tables.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/strings/string16.h"
  13 #include "ui/events/ozone/layout/events_ozone_layout_export.h"
  14 #include "ui/events/ozone/layout/keyboard_layout_engine.h"
  15 #include "ui/events/ozone/layout/xkb/scoped_xkb.h"
  16 #include "ui/events/ozone/layout/xkb/xkb_key_code_converter.h"
  17
  18 namespace ui {
  19
  20 class EVENTS_OZONE_LAYOUT_EXPORT XkbKeyboardLayoutEngine
  21     : public KeyboardLayoutEngine {
  22  public:
  23   XkbKeyboardLayoutEngine(const XkbKeyCodeConverter& converter);
  24   virtual ~XkbKeyboardLayoutEngine();
  25
  26   // KeyboardLayoutEngine:
  27   virtual bool CanSetCurrentLayout() const override;
  28   virtual bool SetCurrentLayoutByName(const std::string& layout_name) override;
  29
  30   virtual bool UsesISOLevel5Shift() const override;
  31   virtual bool UsesAltGr() const override;
  32
  33   virtual bool Lookup(DomCode dom_code,
  34                       int flags,
  35                       DomKey* dom_key,
  36                       base::char16* character,
  37                       KeyboardCode* key_code,
  38                       uint32* platform_keycode) const override;
  39
  40  protected:
  41   // Table for EventFlagsToXkbFlags().
  42   struct XkbFlagMapEntry {
  43     int ui_flag;
  44     xkb_mod_mask_t xkb_flag;
  45   };
  46   std::vector<XkbFlagMapEntry> xkb_flag_map_;
  47
  48   // Determines the Windows-based KeyboardCode (VKEY) for a character key,
  49   // accounting for non-US layouts. May return VKEY_UNKNOWN, in which case the
  50   // caller should use |DomCodeToNonLocatedKeyboardCode()| as a last resort.
  51   KeyboardCode DifficultKeyboardCode(DomCode dom_code,
  52                                      int ui_flags,
  53                                      xkb_keycode_t xkb_keycode,
  54                                      xkb_mod_mask_t xkb_flags,
  55                                      xkb_keysym_t xkb_keysym,
  56                                      DomKey dom_key,
  57                                      base::char16 character) const;
  58
  59   // Maps DomCode to xkb_keycode_t.
  60   const XkbKeyCodeConverter& key_code_converter_;
  61
  62  private:
  63   // Sets a new XKB keymap. This updates xkb_state_ (which takes ownership
  64   // of the keymap), and updates xkb_flag_map_ for the new keymap.
  65   void SetKeymap(xkb_keymap* keymap);
  66
  67   // Returns the XKB modifiers flags corresponding to the given EventFlags.
  68   xkb_mod_mask_t EventFlagsToXkbFlags(int ui_flags) const;
  69
  70   // Determines the XKB KeySym and character associated with a key.
  71   // Returns true on success. This is virtual for testing.
  72   virtual bool XkbLookup(xkb_keycode_t xkb_keycode,
  73                          xkb_mod_mask_t xkb_flags,
  74                          xkb_keysym_t* xkb_keysym,
  75                          base::char16* character) const;
  76
  77   // Helper for difficult VKEY lookup. If |ui_flags| matches |base_flags|,
  78   // returns |base_character|; otherwise returns the XKB character for
  79   // the keycode and mapped |ui_flags|.
  80   base::char16 XkbSubCharacter(xkb_keycode_t xkb_keycode,
  81                                xkb_mod_mask_t base_flags,
  82                                base::char16 base_character,
  83                                int ui_flags) const;
  84
  85   // libxkbcommon uses explicit reference counting for its structures,
  86   // so we need to trigger its cleanup.
  87   scoped_ptr<xkb_context, XkbContextDeleter> xkb_context_;
  88   scoped_ptr<xkb_state, XkbStateDeleter> xkb_state_;
  89 };
  90
  91 }  // namespace ui
  92
  93 #endif  // UI_EVENTS_OZONE_LAYOUT_XKB_XKB_KEYBOARD_LAYOUT_ENGINE_H_