text: /*
   * charset.h - Character set implementation
   *
   *   Copyright (c) 2000-2019  Shiro Kawai  <shiro@acm.org>
   *
   *   Redistribution and use in source and binary forms, with or without
   *   modification, are permitted provided that the following conditions
   *   are met:
   *
   *   1. Redistributions of source code must retain the above copyright
   *      notice, this list of conditions and the following disclaimer.
   *
   *   2. Redistributions in binary form must reproduce the above copyright
   *      notice, this list of conditions and the following disclaimer in the
   *      documentation and/or other materials provided with the distribution.
   *
   *   3. Neither the name of the authors nor the names of its contributors
   *      may be used to endorse or promote products derived from this
   *      software without specific prior written permission.
   *
   *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
   *   TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   *   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   *   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef GAUCHE_CHARSET_H
  #define GAUCHE_CHARSET_H
  
  /* We implement char-sets as hybrid of bitmap and binary tree.
   *
   * Bitmap is used for "small" characters, i.e. characters between
   * U+0000 and U+007F.  There, each bit represents whether the
   * character is in the set (1) or not (0).
   *
   * For larger characters, we keep the range of included chars
   * in a binary tree.  For each entry, its key is the start char code
   * and its value is the end char code (inclusive).
   * For example, if the character set has characters between
   * U+3040 and U+30FF, and U+4E00 and U+9FBF, then the tree has
   * the following entries:
   *   #x3040 => #x30ff, #x4e00 => #x9fbf.
   *
   * We have mutable char-set (default) and immutable or frozen char-set.
   * Mutable char-set uses ScmTreeCore for the large characters.  Immutable
   * char-set uses flat u32vector, sorted by the key and accessed by binary
   * search.
   */
  
  #define SCM_CHAR_SET_SMALL_CHARS 128
  
  struct ScmCharSetRec {
      SCM_HEADER;
      ScmBits small[SCM_BITS_NUM_WORDS(SCM_CHAR_SET_SMALL_CHARS)];
      u_int flags;
      union {
          ScmTreeCore tree;
          struct {
              ScmSize size; /* size of vec.  # of entries is half of this */
              const uint32_t *vec; 
              uint32_t ivec[2]; /* if size==2, vec points here */
          } frozen;
      } large;
  };
  
  typedef enum {
      SCM_CHAR_SET_LARGE = 1,
      SCM_CHAR_SET_IMMUTABLE = 2,
  } ScmCharSetType;
  
  SCM_CLASS_DECL(Scm_CharSetClass);
  #define SCM_CLASS_CHAR_SET  (&Scm_CharSetClass)
  #define SCM_CHAR_SET(obj)   ((ScmCharSet*)obj)
  #define SCM_CHAR_SET_P(obj) SCM_XTYPEP(obj, SCM_CLASS_CHAR_SET)
  
  #define SCM_CHAR_SET_LARGE_P(obj) \
      (SCM_CHAR_SET(obj)->flags & SCM_CHAR_SET_LARGE)
  #define SCM_CHAR_SET_IMMUTABLE_P(obj) \
      (SCM_CHAR_SET(obj)->flags & SCM_CHAR_SET_IMMUTABLE)
  
  /* for backward compatibility.  deprecated. */
  #define SCM_CLASS_CHARSET   SCM_CLASS_CHAR_SET
  #define SCM_CHARSET(obj)    SCM_CHAR_SET(obj)
  #define SCM_CHARSETP(obj)   SCM_CHAR_SET_P(obj)
  
  SCM_EXTERN ScmObj Scm_MakeEmptyCharSet(void);
  SCM_EXTERN ScmObj Scm_MakeImmutableCharSet(const ScmBits *small,
                                             const uint32_t *vec,
                                             size_t size);
  SCM_EXTERN ScmObj Scm_CharSetCopy(ScmCharSet *src);
  SCM_EXTERN ScmObj Scm_CharSetFreeze(ScmCharSet *src);
  SCM_EXTERN ScmObj Scm_CharSetFreezeX(ScmCharSet *src);
  SCM_EXTERN int    Scm_CharSetEq(ScmCharSet *x, ScmCharSet *y);
  SCM_EXTERN int    Scm_CharSetLE(ScmCharSet *x, ScmCharSet *y);
  SCM_EXTERN ScmObj Scm_CharSetAddRange(ScmCharSet *cs,
                                        ScmChar from, ScmChar to);
  SCM_EXTERN ScmObj Scm_CharSetAdd(ScmCharSet *dest, ScmCharSet *src);
  SCM_EXTERN ScmObj Scm_CharSetComplement(ScmCharSet *cs);
  SCM_EXTERN ScmObj Scm_CharSetCaseFold(ScmCharSet *cs);
  SCM_EXTERN ScmObj Scm_CharSetRanges(ScmCharSet *cs);
  SCM_EXTERN ScmObj Scm_CharSetRead(ScmPort *input, int *complement_p,
                                    int error_p, int bracket_syntax);
  SCM_EXTERN int    Scm_CharSetParseCategory(ScmPort *input, char ch);
  
  SCM_EXTERN int    Scm_CharSetContains(ScmCharSet *cs, ScmChar c);
  SCM_EXTERN void   Scm_CharSetDump(ScmCharSet *cs, ScmPort *port);
  
  #endif /*GAUCHE_CHARSET_H*/
  