gnulib/lib/unictype/categ_of.c

/* Categories of Unicode characters.
   Copyright (C) 2002, 2006-2007, 2009-2020 Free Software Foundation, Inc.
   Written by Bruno Haible <bruno@clisp.org>, 2002.

   This program is free software: you can redistribute it and/or modify it
   under the terms of the GNU Lesser General Public License as published
   by the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public License
   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include "unictype.h"

/* Define u_category table.  */
#include "categ_of.h"

static inline int
lookup_withtable (ucs4_t uc)
{
  unsigned int index1 = uc >> category_header_0;
  if (index1 < category_header_1)
    {
      int lookup1 = u_category.level1[index1];
      if (lookup1 >= 0)
        {
          unsigned int index2 = (uc >> category_header_2) & category_header_3;
          int lookup2 = u_category.level2[lookup1 + index2];
          if (lookup2 >= 0)
            {
              unsigned int index3 = ((uc & category_header_4) + lookup2) * 5;
              /* level3 contains 5-bit values, packed into 16-bit words.  */
              unsigned int lookup3 =
                (((unsigned int) u_category.level3[index3>>4]
                  | ((unsigned int) u_category.level3[(index3>>4)+1] << 16))
                 >> (index3 % 16))
                & 0x1f;

              return lookup3;
            }
        }
      return 29; /* = log2(UC_CATEGORY_MASK_Cn) */
    }
  return -1;
}

bool
uc_is_general_category_withtable (ucs4_t uc, uint32_t bitmask)
{
  int bit = lookup_withtable (uc);

  if (bit >= 0)
    return ((bitmask >> bit) & 1);
  else
    return false;
}

uc_general_category_t
uc_general_category (ucs4_t uc)
{
  int bit = lookup_withtable (uc);
  uc_general_category_t result;

  if (bit >= 0)
    {
      result.bitmask = 1 << bit;
      result.generic = 1;
      result.lookup.lookup_fn = &uc_is_general_category_withtable;
      return result;
    }
  else
    return _UC_CATEGORY_NONE;
}