reactos/lib/crtdll/old cruft/stdlib/wcstomb.c

   1 /* Copyright (C) 1991, 1992, 1995, 1996, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <msvcrt/stdlib.h>
  20 #include <msvcrt/wchar.h>
  21
  22 #include <msvcrt/errno.h>
  23 #include <msvcrt/wchar.h>
  24
  25 #ifndef EILSEQ
  26 #define EILSEQ EINVAL
  27 #endif
  28
  29 static const wchar_t encoding_mask[] =
  30 {
  31   (wchar_t)~0x7ff, (wchar_t)~0xffff, (wchar_t)~0x1fffff, (wchar_t)~0x3ffffff
  32 };
  33
  34 static const unsigned char encoding_byte[] =
  35 {
  36   0xc0, 0xe0, 0xf0, 0xf8, 0xfc
  37 };
  38
  39 /* The state is for this UTF8 encoding not used.  */
  40 //static mbstate_t internal;
  41
  42
  43 //extern mbstate_t __no_r_state;  /* Defined in mbtowc.c.  */
  44
  45 size_t
  46 __wcrtomb (char *s, wchar_t wc);
  47
  48 /*
  49  * Convert WCHAR into its multibyte character representation,
  50  * putting this in S and returning its length.
  51  *
  52  * Attention: this function should NEVER be intentionally used.
  53  * The interface is completely stupid.  The state is shared between
  54  * all conversion functions.  You should use instead the restartable
  55  * version `wcrtomb'.
  56  *
  57  * @implemented
  58  */
  59 int
  60 wctomb (char *s, wchar_t wchar)
  61 {
  62   /* If S is NULL the function has to return null or not null
  63      depending on the encoding having a state depending encoding or
  64      not.  This is nonsense because any multibyte encoding has a
  65      state.  The ISO C amendment 1 corrects this while introducing the
  66      restartable functions.  We simply say here all encodings have a
  67      state.  */
  68   if (s == NULL)
  69     return 1;
  70
  71   return __wcrtomb (s, wchar);
  72 }
  73
  74
  75 size_t
  76 __wcrtomb (char *s, wchar_t wc)
  77 {
  78   char fake[1];
  79   size_t written = 0;
  80
  81   if (s == NULL)
  82     {
  83       s = fake;
  84       wc = L'\0';
  85     }
  86
  87   if (wc < 0x80)
  88     {
  89       /* It's a one byte sequence.  */
  90       if (s != NULL)
  91         *s = (char) wc;
  92       return 1;
  93     }
  94
  95   for (written = 2; written < 6; ++written)
  96     if ((wc & encoding_mask[written - 2]) == 0)
  97       break;
  98
  99   if (s != NULL)
 100     {
 101       size_t cnt = written;
 102       s[0] = encoding_byte[cnt - 2];
 103
 104       --cnt;
 105       do
 106         {
 107           s[cnt] = 0x80 | (wc & 0x3f);
 108           wc >>= 6;
 109         }
 110       while (--cnt > 0);
 111       s[0] |= wc;
 112     }
 113
 114   return written;
 115 }