1  /* Simple case mapping for Unicode characters.
       2     Copyright (C) 2002, 2006, 2009-2023 Free Software Foundation, Inc.
       3     Written by Bruno Haible <bruno@clisp.org>, 2009.
       4  
       5     This file is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU Lesser General Public License as
       7     published by the Free Software Foundation; either version 2.1 of the
       8     License, or (at your option) any later version.
       9  
      10     This file is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      13     GNU Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public License
      16     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      17  
      18  ucs4_t
      19  FUNC (ucs4_t uc)
      20  {
      21    unsigned int index1 = uc >> mapping_header_0;
      22    if (index1 < mapping_header_1)
      23      {
      24        int lookup1 = u_mapping.level1[index1];
      25        if (lookup1 >= 0)
      26          {
      27            unsigned int index2 = (uc >> mapping_header_2) & mapping_header_3;
      28            int lookup2 = u_mapping.level2[lookup1 + index2];
      29            if (lookup2 >= 0)
      30              {
      31                unsigned int index3 = (uc & mapping_header_4);
      32                int lookup3 = u_mapping.level3[lookup2 + index3];
      33  
      34                return uc + lookup3;
      35              }
      36          }
      37      }
      38    return uc;
      39  }