Re: Free modifier key assignment (OS X)

[YAMAMOTO Mitsuharu]

I tried to tackle some issues about mapping the laptop `fn' key to an
Emacs modifier. (This functionality was originally provided by David
Reitter.)

  /* TODO / known issues

  - Fn-Shift-j is regonized as Fn-j and not Fn-J.
  The above table always translates to lower characters. We need to use
  the KCHR keyboard resource (KeyTranslate() ) to map k->K and 8->*.

  - The table is meant for English language keyboards, and it will work
  for many others with the exception of key combinations like Fn-ö on
  a German keyboard, which is currently mapped to Fn-;.
  How to solve this without keeping separate tables for all keyboards
  around? KeyTranslate isn't of much help here, as it only takes a 16-bit
  value for keycode with the modifiers in he high byte, i.e. no room for the
  Fn modifier. That's why we need the table.

  */

I think the first one is solved by the patch below, but I can't test
the second one.  Could non-US keyboard users test if the patch below
works for you?  Fn-ö may be recognized as H-\232 instead of H-ö on a
German keyboard even if you set (setq mac-function-modifier 'hyper),
but this is another issue
(http://lists.gnu.org/archive/html/emacs-pretest-bug/2006-05/msg00033.html).

                                     YAMAMOTO Mitsuharu
                                address@hidden

Index: src/macterm.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/macterm.c,v
retrieving revision 1.172
diff -c -r1.172 macterm.c
*** src/macterm.c       20 May 2006 07:15:22 -0000      1.172
--- src/macterm.c       20 May 2006 07:57:56 -0000
***************
*** 9629,9635 ****
    return *xKeySym != 0;
  }
  
! static unsigned char fn_keycode_to_xkeysym_table[] = {
    /*0x00*/ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /*0x10*/ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /*0x20*/ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
--- 9629,9635 ----
    return *xKeySym != 0;
  }
  
! static unsigned char fn_keycode_to_keycode_table[] = {
    /*0x00*/ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /*0x10*/ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /*0x20*/ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
***************
*** 9639,9662 ****
    /*0x38*/ 0, 0, 0, 0,
    /*0x3C*/ 0, 0, 0, 0,
  
!   /*0x40*/ 0, 0x2e /*kp-. = .*/, 0, 0x50 /*kp-* = 'p'*/,
!   /*0x44*/ 0, '/' /*kp-+*/, 0, 0,
!   /*0x48*/ 0, 0, 0, 0x30 /*kp-/ = '0'*/,
!   /*0x4C*/ 0, 0, 0x3b /*kp-- = ';'*/, 0,
! 
!   /*0x50*/ 0, 0x2d /*kp-= = '-'*/, 0x6d /*kp-0 = 'm'*/, 0x6a /*kp-1 = 'j'*/,
!   /*0x54*/ 0x6b /*kp-2 = 'k'*/, 0x6c /*kp-3 = 'l'*/, 'u' /*kp-4*/, 'i' 
/*kp-5*/,
!   /*0x58*/ 'o' /*kp-6*/, '7' /*kp-7*/, 0, '8' /*kp-8*/,
!   /*0x5C*/ '9' /*kp-9*/, 0, 0, 0,
  
    /*0x60*/ 0, 0, 0, 0,
    /*0x64*/ 0, 0, 0, 0,
    /*0x68*/ 0, 0, 0, 0,
    /*0x6C*/ 0, 0, 0, 0,
  
!   /*0x70*/ 0, 0, 0, 0,
!   /*0x74*/ 0, 0, 0, 0,
!   /*0x78*/ 0, 0, 0, 0,
    /*0x7C*/ 0, 0, 0, 0
  };
  static int
--- 9639,9662 ----
    /*0x38*/ 0, 0, 0, 0,
    /*0x3C*/ 0, 0, 0, 0,
  
!   /*0x40*/ 0, 0x2f /*kp-. -> '.'*/, 0, 0x23 /*kp-* -> 'p'*/,
!   /*0x44*/ 0, 0x2c /*kp-+ -> '/'*/, 0, 0x16 /*clear -> '6'*/,
!   /*0x48*/ 0, 0, 0, 0x1d /*kp-/ -> '0'*/,
!   /*0x4C*/ 0x24 /*kp-enter -> return*/, 0, 0x29 /*kp-- -> ';'*/, 0,
! 
!   /*0x50*/ 0, 0x1b /*kp-= -> '-'*/, 0x2e /*kp-0 -> 'm'*/, 0x26 /*kp-1 -> 
'j'*/,
!   /*0x54*/ 0x28 /*kp-2 -> 'k'*/, 0x25 /*kp-3 -> 'l'*/, 0x20 /*kp-4 -> 'u'*/, 
0x22 /*kp-5 ->'i'*/,
!   /*0x58*/ 0x1f /*kp-6 -> 'o'*/, 0x1a /*kp-7 -> '7'*/, 0, 0x1c /*kp-8 -> 
'8'*/,
!   /*0x5C*/ 0x19 /*kp-9 -> '9'*/, 0, 0, 0,
  
    /*0x60*/ 0, 0, 0, 0,
    /*0x64*/ 0, 0, 0, 0,
    /*0x68*/ 0, 0, 0, 0,
    /*0x6C*/ 0, 0, 0, 0,
  
!   /*0x70*/ 0, 0, 0, 0x7b /*home -> left*/,
!   /*0x74*/ 0x7e /*pgup -> up*/, 0x33 /*delete -> backspace*/, 0, 0x7c /*end 
-> right*/,
!   /*0x78*/ 0, 0x7d /*pgdown -> down*/, 0, 0,
    /*0x7C*/ 0, 0, 0, 0
  };
  static int
***************
*** 9673,9682 ****
  
    /* TODO / known issues
  
!   - Fn-Shift-j is regonized as Fn-j and not Fn-J.
!   The above table always translates to lower characters. We need to use
!   the KCHR keyboard resource (KeyTranslate() ) to map k->K and 8->*.
! 
    - The table is meant for English language keyboards, and it will work
    for many others with the exception of key combinations like Fn-ö on
    a German keyboard, which is currently mapped to Fn-;.
--- 9673,9679 ----
  
    /* TODO / known issues
  
!   !!!! NEED TO CHECK IF IT REALLY DOESN'T WORK WITH NON-US KEYBOARDS. !!!!!
    - The table is meant for English language keyboards, and it will work
    for many others with the exception of key combinations like Fn-ö on
    a German keyboard, which is currently mapped to Fn-;.
***************
*** 9693,9699 ****
        err = GetEventParameter (eventRef, kEventParamKeyModifiers, typeUInt32,
                               NULL, sizeof (UInt32), NULL, &mods);
        if (err == noErr && mods & kEventKeyModifierFnMask)
!       {  *newCode = fn_keycode_to_xkeysym_table [keyCode & 0x7f];
  
          return (*newCode != 0);
        }
--- 9690,9696 ----
        err = GetEventParameter (eventRef, kEventParamKeyModifiers, typeUInt32,
                               NULL, sizeof (UInt32), NULL, &mods);
        if (err == noErr && mods & kEventKeyModifierFnMask)
!       {  *newCode = fn_keycode_to_keycode_table [keyCode & 0x7f];
  
          return (*newCode != 0);
        }
***************
*** 9702,9751 ****
    return false;
  }
  
- static int
- backtranslate_modified_keycode(int mods, int keycode, int def)
- {
-   EventModifiers mapped_modifiers =
-     (NILP (Vmac_control_modifier) ? 0 : controlKey)
-     | (NILP (Vmac_option_modifier) ? 0 : optionKey)
-     | (NILP (Vmac_command_modifier) ? 0 : cmdKey);
- 
-   if (mods & mapped_modifiers)
-     {
-       /* This code comes from Keyboard Resource,
-        Appendix C of IM - Text.  This is necessary
-        since shift is ignored in KCHR table
-        translation when option or command is pressed.
-        It also does not translate correctly
-        control-shift chars like C-% so mask off shift
-        here also.
- 
-        Not done for combinations with the option key (alt)
-        unless it is to be caught by Emacs:  this is
-        to preserve key combinations translated by the OS
-        such as Alt-3.
-       */
-       /* Mask off modifier keys that are mapped to some Emacs
-        modifiers.  */
-       int new_modifiers = mods & ~mapped_modifiers;
-       /* set high byte of keycode to modifier high byte*/
-       int new_keycode = keycode | new_modifiers;
-       Ptr kchr_ptr = (Ptr) GetScriptManagerVariable (smKCHRCache);
-       unsigned long some_state = 0;
-       return (int) KeyTranslate (kchr_ptr, new_keycode,
-                                &some_state) & 0xff;
-       /* TO DO: Recognize two separate resulting characters, "for
-        example, when the user presses Option-E followed by N, you
-        can map this through the KeyTranslate function using the
-        U.S. 'KCHR' resource to produce ´n, which KeyTranslate
-        returns as two characters in the bytes labeled Character code
-        1 and Character code 2." (from Carbon API doc) */
- 
-     }
-   else
-     return def;
- }
- 
  
  #if !USE_CARBON_EVENTS
  static RgnHandle mouse_region = NULL;
--- 9699,9704 ----
***************
*** 10338,10343 ****
--- 10291,10299 ----
          {
            int keycode = (er.message & keyCodeMask) >> 8;
            int xkeysym;
+           static SInt16 last_key_script = -1;
+           SInt16 current_key_script;
+           UInt32 modifiers = er.modifiers, mapped_modifiers;
  
  #if USE_CARBON_EVENTS && defined (MAC_OSX)
            /* When using Carbon Events, we need to pass raw keyboard
***************
*** 10358,10392 ****
            if (er.what == keyUp)
              break;
  
- #if 0
-           if (dpyinfo->x_focus_frame == NULL)
-             {
-               /* Beep if keyboard input occurs when all the frames
-                  are invisible.  */
-               SysBeep (1);
-               break;
-             }
- #endif
- 
-           {
-             static SInt16 last_key_script = -1;
-             SInt16 current_key_script = GetScriptManagerVariable 
(smKeyScript);
- 
-             if (last_key_script != current_key_script)
-               {
-                 struct input_event event;
- 
-                 EVENT_INIT (event);
-                 event.kind = LANGUAGE_CHANGE_EVENT;
-                 event.arg = Qnil;
-                 event.code = current_key_script;
-                 event.timestamp = timestamp;
-                 kbd_buffer_store_event (&event);
-                 count++;
-               }
-             last_key_script = current_key_script;
-           }
- 
            ObscureCursor ();
  
            f = mac_focus_frame (dpyinfo);
--- 10314,10319 ----
***************
*** 10398,10442 ****
                dpyinfo->mouse_face_hidden = 1;
              }
  
!           /* translate the keycode back to determine the original key */
!           /* Convert key code if function key is pressed.
!              Otherwise, if non-ASCII-event, take care of that
!              without re-translating the key code. */
! #if USE_CARBON_EVENTS
!           if (convert_fn_keycode (eventRef, keycode, &xkeysym))
              {
!               inev.code = xkeysym;
!               /* this doesn't work - tried to add shift modifiers */
!                 inev.code =
!                   backtranslate_modified_keycode(er.modifiers & (~0x2200),
!                                                  xkeysym | 0x80,  xkeysym);
!               inev.kind = ASCII_KEYSTROKE_EVENT;
              }
-           else
- #endif
-             if (keycode_to_xkeysym (keycode, &xkeysym))
-               {
-                 inev.code = 0xff00 | xkeysym;
-                 inev.kind = NON_ASCII_KEYSTROKE_EVENT;
-               }
-             else
-               {
-                 inev.code =
-                   backtranslate_modified_keycode(er.modifiers, keycode,
-                                                  er.message & charCodeMask);
-                 inev.kind = ASCII_KEYSTROKE_EVENT;
-               }
-         }
  
  #if USE_CARBON_EVENTS
!         inev.modifiers = mac_event_to_emacs_modifiers (eventRef);
  #else
!         inev.modifiers = mac_to_emacs_modifiers (er.modifiers);
  #endif
!         inev.modifiers |= (extra_keyboard_modifiers
!                            & (meta_modifier | alt_modifier
!                               | hyper_modifier | super_modifier));
!         XSETFRAME (inev.frame_or_window, f);
          break;
  
        case kHighLevelEvent:
--- 10325,10484 ----
                dpyinfo->mouse_face_hidden = 1;
              }
  
!           current_key_script = GetScriptManagerVariable (smKeyScript);
!           if (last_key_script != current_key_script)
              {
!               struct input_event event;
! 
!               EVENT_INIT (event);
!               event.kind = LANGUAGE_CHANGE_EVENT;
!               event.arg = Qnil;
!               event.code = current_key_script;
!               event.timestamp = timestamp;
!               kbd_buffer_store_event (&event);
!               count++;
!               last_key_script = current_key_script;
              }
  
  #if USE_CARBON_EVENTS
!           inev.modifiers = mac_event_to_emacs_modifiers (eventRef);
  #else
!           inev.modifiers = mac_to_emacs_modifiers (er.modifiers);
! #endif
!           inev.modifiers |= (extra_keyboard_modifiers
!                              & (meta_modifier | alt_modifier
!                                 | hyper_modifier | super_modifier));
! 
!           XSETFRAME (inev.frame_or_window, f);
! 
! #if USE_CARBON_EVENTS
!           {
!             int tmp_code;
! 
!             if (convert_fn_keycode (eventRef, keycode, &tmp_code))
!               keycode = tmp_code;
!           }
  #endif
!           if (keycode_to_xkeysym (keycode, &xkeysym))
!             {
!               inev.kind = NON_ASCII_KEYSTROKE_EVENT;
!               inev.code = 0xff00 | xkeysym;
!               break;
!             }
! 
! #if USE_CARBON_EVENTS
!           GetEventParameter (eventRef, kEventParamKeyModifiers,
!                              typeUInt32, NULL,
!                              sizeof (UInt32), NULL, &modifiers);
! #endif
! 
!           mapped_modifiers =
!             (NILP (Vmac_control_modifier) ? 0 : controlKey)
!             | (NILP (Vmac_option_modifier) ? 0 : optionKey)
!             | (NILP (Vmac_command_modifier) ? 0 : cmdKey)
! #ifdef MAC_OSX
!             | (NILP (Vmac_function_modifier) ? 0 : kEventKeyModifierFnMask)
! #endif
!             ;
! 
!           if (!(modifiers & mapped_modifiers))
!             {
!               inev.kind = ASCII_KEYSTROKE_EVENT;
!               inev.code = er.message & charCodeMask;
!             }
!           else
!             {
!               /* translate the keycode back to determine the
!                  original key */
! #ifdef MAC_OSX
!               static SInt16 last_key_layout_id = 0;
!               static Handle uchr_handle = (Handle)-1;
!               SInt16 current_key_layout_id =
!                 GetScriptVariable (current_key_script, smScriptKeys);
! 
!               if (uchr_handle == (Handle)-1
!                   || last_key_layout_id != current_key_layout_id)
!                 {
!                   uchr_handle = GetResource ('uchr', current_key_layout_id);
!                   last_key_layout_id = current_key_layout_id;
!                 }
! 
!               if (uchr_handle)
!                 {
!                   OSStatus status;
!                   UInt16 key_action = er.what - keyDown;
!                   UInt32 modifier_key_state =
!                     (modifiers & ~mapped_modifiers) >> 8;
!                   UInt32 keyboard_type = LMGetKbdType ();
!                   SInt32 dead_key_state = 0;
!                   UniChar code;
!                   UniCharCount actual_length;
! 
!                   status = UCKeyTranslate ((UCKeyboardLayout *)*uchr_handle,
!                                            keycode, key_action,
!                                            modifier_key_state,
!                                            keyboard_type, 0,
!                                            &dead_key_state,
!                                            1, &actual_length, &code);
!                   if (status == noErr && actual_length == 1)
!                     {
!                       int charset_id, c1, c2;
! 
!                       if (code < 0x80)
!                         {
!                           inev.kind = ASCII_KEYSTROKE_EVENT;
!                           inev.code = code;
!                         }
!                       else if (code < 0x100)
!                         {
!                           if (code < 0xA0)
!                             charset_id = CHARSET_8_BIT_CONTROL;
!                           else
!                             charset_id = charset_latin_iso8859_1;
!                           inev.kind = MULTIBYTE_CHAR_KEYSTROKE_EVENT;
!                           inev.code = MAKE_CHAR (charset_id, code, 0);
!                         }
!                       else
!                         {
!                           if (code < 0x2500)
!                             charset_id = charset_mule_unicode_0100_24ff,
!                               code -= 0x100;
!                           else if (code < 0xE000)
!                             charset_id = charset_mule_unicode_2500_33ff,
!                               code -= 0x2500;
!                           else
!                             charset_id = charset_mule_unicode_e000_ffff,
!                               code -= 0xE000;
!                           c1 = (code / 96) + 32, c2 = (code % 96) + 32;
!                           inev.kind = MULTIBYTE_CHAR_KEYSTROKE_EVENT;
!                           inev.code = MAKE_CHAR (charset_id, c1, c2);
!                         }
!                     }
!                 }
! #endif        /* MAC_OSX */
! 
!               if (inev.kind == NO_EVENT)
!                 {
!                   /* This code comes from Keyboard Resource,
!                      Appendix C of IM - Text.  This is necessary
!                      since shift is ignored in KCHR table
!                      translation when option or command is pressed.
!                      It also does not translate correctly
!                      control-shift chars like C-% so mask off shift
!                      here also.  */
!                   /* Mask off modifier keys that are mapped to some
!                      Emacs modifiers.  */
!                   int new_modifiers = er.modifiers & ~mapped_modifiers;
!                   /* set high byte of keycode to modifier high byte*/
!                   int new_keycode = keycode | new_modifiers;
!                   Ptr kchr_ptr = (Ptr) GetScriptManagerVariable (smKCHRCache);
!                   unsigned long some_state = 0;
!                   inev.code = (int) KeyTranslate (kchr_ptr, new_keycode,
!                                                   &some_state) & 0xff;
!                   inev.kind = ASCII_KEYSTROKE_EVENT;
!                 }
!             }
!         }
          break;
  
        case kHighLevelEvent: