reactos/lib/crtdll/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 <crtdll/stdlib.h>
  20 #include <crtdll/wchar.h>
  21
  22 #include <crtdll/errno.h>
  23 #include <crtdll/wchar.h>
  24 #include <crtdll/internal/file.h>
  25
  26 #ifndef EILSEQ
  27 #define EILSEQ EINVAL
  28 #endif
  29
  30 static const wchar_t encoding_mask[] =
  31 {
  32   (wchar_t)~0x7ff, (wchar_t)~0xffff, (wchar_t)~0x1fffff, (wchar_t)~0x3ffffff
  33 };
  34
  35 static const unsigned char encoding_byte[] =
  36 {
  37   0xc0, 0xe0, 0xf0, 0xf8, 0xfc
  38 };
  39
  40 /* The state is for this UTF8 encoding not used.  */
  41 //static mbstate_t internal;
  42
  43
  44 //extern mbstate_t __no_r_state;  /* Defined in mbtowc.c.  */
  45
  46 size_t
  47 __wcrtomb (char *s, wchar_t wc);
  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 int
  57 wctomb (char *s, wchar_t wchar)
  58 {
  59   /* If S is NULL the function has to return null or not null
  60      depending on the encoding having a state depending encoding or
  61      not.  This is nonsense because any multibyte encoding has a
  62      state.  The ISO C amendment 1 corrects this while introducing the
  63      restartable functions.  We simply say here all encodings have a
  64      state.  */
  65   if (s == NULL)
  66     return 1;
  67
  68   return __wcrtomb (s, wchar);
  69 }
  70
  71
  72 size_t
  73 __wcrtomb (char *s, wchar_t wc)
  74 {
  75   char fake[1];
  76   size_t written = 0;
  77
  78
  79
  80   if (s == NULL)
  81     {
  82       s = fake;
  83       wc = L'\0';
  84     }
  85
  86   /* Store the UTF8 representation of WC.  */
  87   if (wc < 0 || wc > 0x7fffffff)
  88     {
  89       /* This is no correct ISO 10646 character.  */
  90       __set_errno (EILSEQ);
  91       return (size_t) -1;
  92     }
  93
  94   if (wc < 0x80)
  95     {
  96       /* It's a one byte sequence.  */
  97       if (s != NULL)
  98         *s = (char) wc;
  99       return 1;
 100     }
 101
 102   for (written = 2; written < 6; ++written)
 103     if ((wc & encoding_mask[written - 2]) == 0)
 104       break;
 105
 106   if (s != NULL)
 107     {
 108       size_t cnt = written;
 109       s[0] = encoding_byte[cnt - 2];
 110
 111       --cnt;
 112       do
 113         {
 114           s[cnt] = 0x80 | (wc & 0x3f);
 115           wc >>= 6;
 116         }
 117       while (--cnt > 0);
 118       s[0] |= wc;
 119     }
 120
 121   return written;
 122 }