gnu/dist/gettext/gettext-tools/lib/ucs4-utf16.h

   1 /* Conversion UCS-4 to UTF-16.
   2    Copyright (C) 2002 Free Software Foundation, Inc.
   3    Written by Bruno Haible <haible@clisp.cons.org>, 2002.
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 2, or (at your option)
   8 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
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program; if not, write to the Free Software
  17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19
  20 #include <stddef.h>
  21
  22 /* Return the length (number of units) of the UTF-16 representation of uc,
  23    after storing it at S.  Return -1 upon failure, -2 if the number of
  24    available units, N, is too small.  */
  25 static int
  26 u16_uctomb_aux (unsigned short *s, unsigned int uc, int n)
  27 {
  28   if (uc >= 0x10000)
  29     {
  30       if (uc < 0x110000)
  31         {
  32           if (n >= 2)
  33             {
  34               s[0] = 0xd800 + ((uc - 0x10000) >> 10);
  35               s[1] = 0xdc00 + ((uc - 0x10000) & 0x3ff);
  36               return 2;
  37             }
  38         }
  39       else
  40         return -1;
  41     }
  42   return -2;
  43 }
  44
  45 static inline int
  46 u16_uctomb (unsigned short *s, unsigned int uc, int n)
  47 {
  48   if (uc < 0x10000 && n > 0)
  49     {
  50       s[0] = uc;
  51       return 1;
  52     }
  53   else
  54     return u16_uctomb_aux (s, uc, n);
  55 }