lib/unistr/u-strpbrk.h

   1 /* Search for some characters in UTF-8/UTF-16/UTF-32 string.
   2    Copyright (C) 1999, 2002, 2006, 2009-2021 Free Software Foundation, Inc.
   3    Written by Bruno Haible <bruno@clisp.org>, 2002.
   4
   5    This program is free software: you can redistribute it and/or modify it
   6    under the terms of the GNU Lesser General Public License as published
   7    by the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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 GNU
  13    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 UNIT *
  19 FUNC (const UNIT *str, const UNIT *accept)
  20 {
  21   /* Optimize two cases.  */
  22   if (accept[0] == 0)
  23     return NULL;
  24   {
  25     ucs4_t uc;
  26     int count = U_STRMBTOUC (&uc, accept);
  27     if (count >= 0 && accept[count] == 0)
  28       return U_STRCHR (str, uc);
  29   }
  30   /* General case.  */
  31   {
  32     const UNIT *ptr = str;
  33
  34     for (;;)
  35       {
  36         ucs4_t uc;
  37         int count = U_STRMBTOUC (&uc, ptr);
  38         if (count <= 0)
  39           break;
  40         if (U_STRCHR (accept, uc))
  41           return (UNIT *) ptr;
  42         ptr += count;
  43       }
  44     return NULL;
  45   }
  46 }