kc3-lang/libxkbcommon/changes

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• Hash : 9ede705b
  Author :
  Date : 2025-04-13T09:50:18
  

  state: Capitalization transformation in xkb_state_key_get_syms
  
  Previously `xkb_state_key_get_syms()` did not perform capitalization
  tranformation, while `xkb_state_key_get_one_sym()` does perform it.
  
  This is unfortunate if we want to promote the use of multiple keysyms
  per levels.
  
  The API make it difficult to change now though: we return a pointer to
  an immutable array rather than filling a buffer. While we could use an
  internal buffer in `xkb_state`, this option would limit the API to
  *sequential* calls of `xkb_state_key_get_syms()` or require some buffer
  handling (e.g. rotation).
  
  Instead we now store the capitalization directly in `xkb_level`. We
  modified `xkb_level` like so (see below for discussion about the size):
  
  ```diff
   struct xkb_level {
  -    unsigned int num_syms;
  +    uint16_t     num_syms;
  -    unsigned int num_actions;
  +    uint16_t     num_actions;
  +    union {
  +        /** num_syms == 1: Upper keysym */
  +        xkb_keysym_t upper;
  +        /** num_syms >  1: Indicate if `syms` contains the upper case
  +         *                 keysyms after the lower ones. */
  +        bool has_upper;
  +    };
       union {
           xkb_keysym_t sym;          /* num_syms == 1 */
           xkb_keysym_t *syms;        /* num_syms > 1  */
       } s;
       union {
           union xkb_action action;   /* num_actions == 1 */
           union xkb_action *actions; /* num_actions >  1 */
       } a;
   };
  ```
  
  - When `level.num_syms` <= 1, we store the upper keysym in `level.upper`.
  - Else if there no cased syms, we set `level.has_upper` to false.
  - Else if there are some cased syms, we set `level.has_upper`` to `true`
    and we double the original size of `level.s.syms`, but *without*
    modifying `level.num_syms`. We then append the transformed keysyms
    right after the original ones, so that we can access them by a simple
    pointer operation: `level.s.syms + level.num_syms`.
  
  The memory footprint is *unchanged*, thanks to the reduced fields for
  actions and keysyms counts.
  

• Files

• README.md
• api/
• build/
• tools/

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  Git SSH	git@git.kmx.io:kc3-lang/libxkbcommon.git
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  Description	keymap handling library for toolkits and window systems Upstream Homepage Github Fork Github
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