/* Conversion UTF-8 to UCS-4.
Copyright (C) 2001-2002 Free Software Foundation, Inc.
Written by Bruno Haible <haible@clisp.cons.org>, 2001.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
#include <stddef.h>
/* Return the length (number of units) of the first character in S, putting
its 'ucs4_t' representation in *PUC. */
static int
u8_mbtouc_aux (unsigned int *puc, const unsigned char *s, size_t n)
{
unsigned char c = *s;
if (c >= 0xc2)
{
if (c < 0xe0)
{
if (n >= 2)
{
if ((s[1] ^ 0x80) < 0x40)
{
*puc = ((unsigned int) (c & 0x1f) << 6)
| (unsigned int) (s[1] ^ 0x80);
return 2;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
return n;
}
}
else if (c < 0xf0)
{
if (n >= 3)
{
if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
&& (c >= 0xe1 || s[1] >= 0xa0))
{
*puc = ((unsigned int) (c & 0x0f) << 12)
| ((unsigned int) (s[1] ^ 0x80) << 6)
| (unsigned int) (s[2] ^ 0x80);
return 3;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
return n;
}
}
else if (c < 0xf8)
{
if (n >= 4)
{
if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
&& (s[3] ^ 0x80) < 0x40
&& (c >= 0xf1 || s[1] >= 0x90)
#if 1
&& (c < 0xf4 || (c == 0xf4 && s[1] < 0x90))
#endif
)
{
*puc = ((unsigned int) (c & 0x07) << 18)
| ((unsigned int) (s[1] ^ 0x80) << 12)
| ((unsigned int) (s[2] ^ 0x80) << 6)
| (unsigned int) (s[3] ^ 0x80);
return 4;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
return n;
}
}
#if 0
else if (c < 0xfc)
{
if (n >= 5)
{
if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
&& (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40
&& (c >= 0xf9 || s[1] >= 0x88))
{
*puc = ((unsigned int) (c & 0x03) << 24)
| ((unsigned int) (s[1] ^ 0x80) << 18)
| ((unsigned int) (s[2] ^ 0x80) << 12)
| ((unsigned int) (s[3] ^ 0x80) << 6)
| (unsigned int) (s[4] ^ 0x80);
return 5;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
return n;
}
}
else if (c < 0xfe)
{
if (n >= 6)
{
if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
&& (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40
&& (s[5] ^ 0x80) < 0x40
&& (c >= 0xfd || s[1] >= 0x84))
{
*puc = ((unsigned int) (c & 0x01) << 30)
| ((unsigned int) (s[1] ^ 0x80) << 24)
| ((unsigned int) (s[2] ^ 0x80) << 18)
| ((unsigned int) (s[3] ^ 0x80) << 12)
| ((unsigned int) (s[4] ^ 0x80) << 6)
| (unsigned int) (s[5] ^ 0x80);
return 6;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
return n;
}
}
#endif
}
/* invalid multibyte character */
*puc = 0xfffd;
return 1;
}
static inline int
u8_mbtouc (unsigned int *puc, const unsigned char *s, size_t n)
{
unsigned char c = *s;
if (c < 0x80)
{
*puc = c;
return 1;
}
else
return u8_mbtouc_aux (puc, s, n);
}
