/* Look at first character in UTF-8 string.
Copyright (C) 1999-2002, 2006-2007, 2009-2020 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2001.
This program is free software: you can redistribute it and/or
modify it under the terms of either:
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your
option) any later version.
or
* the GNU General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version.
or both in parallel, as here.
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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#include <config.h>
#if defined IN_LIBUNISTRING
/* Tell unistr.h to declare u8_mbtouc_unsafe as 'extern', not
'static inline'. */
# include "unistring-notinline.h"
#endif
/* Specification. */
#include "unistr.h"
#if !HAVE_INLINE
int
u8_mbtouc_unsafe (ucs4_t *puc, const uint8_t *s, size_t n)
{
uint8_t c = *s;
if (c < 0x80)
{
*puc = c;
return 1;
}
else 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 1;
}
}
else if (c < 0xf0)
{
if (n >= 3)
{
if ((s[1] ^ 0x80) < 0x40)
{
if ((s[2] ^ 0x80) < 0x40)
{
if ((c >= 0xe1 || s[1] >= 0xa0)
&& (c != 0xed || 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 */
*puc = 0xfffd;
return 3;
}
/* invalid multibyte character */
*puc = 0xfffd;
return 2;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
if (n == 1 || (s[1] ^ 0x80) >= 0x40)
return 1;
else
return 2;
}
}
else if (c < 0xf8)
{
if (n >= 4)
{
if ((s[1] ^ 0x80) < 0x40)
{
if ((s[2] ^ 0x80) < 0x40)
{
if ((s[3] ^ 0x80) < 0x40)
{
if ((c >= 0xf1 || s[1] >= 0x90)
&& (c < 0xf4 || (c == 0xf4 && s[1] < 0x90))
)
{
*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 */
*puc = 0xfffd;
return 4;
}
/* invalid multibyte character */
*puc = 0xfffd;
return 3;
}
/* invalid multibyte character */
*puc = 0xfffd;
return 2;
}
/* invalid multibyte character */
}
else
{
/* incomplete multibyte character */
*puc = 0xfffd;
if (n == 1 || (s[1] ^ 0x80) >= 0x40)
return 1;
else if (n == 2 || (s[2] ^ 0x80) >= 0x40)
return 2;
else
return 3;
}
}
}
/* invalid multibyte character */
*puc = 0xfffd;
return 1;
}
#endif