lib/unistr/u8-uctomb.c

   1 /* Store a character in UTF-8 string.
   2    Copyright (C) 2002, 2005-2006, 2009-2010 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 <http://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 #if defined IN_LIBUNISTRING
  21 /* Tell unistr.h to declare u8_uctomb as 'extern', not 'static inline'.  */
  22 # include "unistring-notinline.h"
  23 #endif
  24
  25 /* Specification.  */
  26 #include "unistr.h"
  27
  28 #if !HAVE_INLINE
  29
  30 int
  31 u8_uctomb (uint8_t *s, ucs4_t uc, int n)
  32 {
  33   if (uc < 0x80)
  34     {
  35       if (n > 0)
  36         {
  37           s[0] = uc;
  38           return 1;
  39         }
  40       /* else return -2, below.  */
  41     }
  42   else
  43     {
  44       int count;
  45
  46       if (uc < 0x800)
  47         count = 2;
  48       else if (uc < 0x10000)
  49         {
  50           if (uc < 0xd800 || uc >= 0xe000)
  51             count = 3;
  52           else
  53             return -1;
  54         }
  55 #if 0
  56       else if (uc < 0x200000)
  57         count = 4;
  58       else if (uc < 0x4000000)
  59         count = 5;
  60       else if (uc <= 0x7fffffff)
  61         count = 6;
  62 #else
  63       else if (uc < 0x110000)
  64         count = 4;
  65 #endif
  66       else
  67         return -1;
  68
  69       if (n >= count)
  70         {
  71           switch (count) /* note: code falls through cases! */
  72             {
  73 #if 0
  74             case 6: s[5] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x4000000;
  75             case 5: s[4] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x200000;
  76 #endif
  77             case 4: s[3] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x10000;
  78             case 3: s[2] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0x800;
  79             case 2: s[1] = 0x80 | (uc & 0x3f); uc = uc >> 6; uc |= 0xc0;
  80           /*case 1:*/ s[0] = uc;
  81             }
  82           return count;
  83         }
  84     }
  85   return -2;
  86 }
  87
  88 #endif