mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-08 06:10:06 +00:00
133 lines
3.5 KiB
C
133 lines
3.5 KiB
C
/* UTF-8 to multibyte conversion.
|
|
Copyright (C) 2022-2024 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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 the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <errno.h>
|
|
#include <uchar.h>
|
|
#include <wchar.h>
|
|
|
|
|
|
/* This is the private state used if PS is NULL. */
|
|
static mbstate_t state;
|
|
|
|
size_t
|
|
c8rtomb (char *s, char8_t c8, mbstate_t *ps)
|
|
{
|
|
/* This implementation depends on the converter invoked by wcrtomb not
|
|
needing to retain state in either the top most bit of ps->__count or
|
|
in ps->__value between invocations. This implementation uses the
|
|
top most bit of ps->__count to indicate that trailing code units are
|
|
expected and uses ps->__value to store previously seen code units. */
|
|
|
|
wchar_t wc;
|
|
|
|
if (ps == NULL)
|
|
ps = &state;
|
|
|
|
if (s == NULL)
|
|
{
|
|
/* if 's' is a null pointer, behave as if u8'\0' was passed as 'c8'. If
|
|
this occurs for an incomplete code unit sequence, then an error will
|
|
be reported below. */
|
|
c8 = u8""[0];
|
|
}
|
|
|
|
if (! (ps->__count & 0x80000000))
|
|
{
|
|
/* Initial state. */
|
|
if ((c8 >= 0x80 && c8 <= 0xC1) || c8 >= 0xF5)
|
|
{
|
|
/* An invalid lead code unit. */
|
|
__set_errno (EILSEQ);
|
|
return -1;
|
|
}
|
|
if (c8 >= 0xC2)
|
|
{
|
|
/* A valid lead code unit. */
|
|
ps->__count |= 0x80000000;
|
|
ps->__value.__wchb[0] = c8;
|
|
ps->__value.__wchb[3] = 1;
|
|
return 0;
|
|
}
|
|
/* A single byte (ASCII) code unit. */
|
|
wc = c8;
|
|
}
|
|
else
|
|
{
|
|
char8_t cu1 = ps->__value.__wchb[0];
|
|
if (ps->__value.__wchb[3] == 1)
|
|
{
|
|
/* A single lead code unit was previously seen. */
|
|
if ((c8 < 0x80 || c8 > 0xBF)
|
|
|| (cu1 == 0xE0 && c8 < 0xA0)
|
|
|| (cu1 == 0xED && c8 > 0x9F)
|
|
|| (cu1 == 0xF0 && c8 < 0x90)
|
|
|| (cu1 == 0xF4 && c8 > 0x8F))
|
|
{
|
|
/* An invalid second code unit. */
|
|
__set_errno (EILSEQ);
|
|
return -1;
|
|
}
|
|
if (cu1 >= 0xE0)
|
|
{
|
|
/* A three or four code unit sequence. */
|
|
ps->__value.__wchb[1] = c8;
|
|
++ps->__value.__wchb[3];
|
|
return 0;
|
|
}
|
|
wc = ((cu1 & 0x1F) << 6)
|
|
+ (c8 & 0x3F);
|
|
}
|
|
else
|
|
{
|
|
char8_t cu2 = ps->__value.__wchb[1];
|
|
/* A three or four byte code unit sequence. */
|
|
if (c8 < 0x80 || c8 > 0xBF)
|
|
{
|
|
/* An invalid third or fourth code unit. */
|
|
__set_errno (EILSEQ);
|
|
return -1;
|
|
}
|
|
if (ps->__value.__wchb[3] == 2 && cu1 >= 0xF0)
|
|
{
|
|
/* A four code unit sequence. */
|
|
ps->__value.__wchb[2] = c8;
|
|
++ps->__value.__wchb[3];
|
|
return 0;
|
|
}
|
|
if (cu1 < 0xF0)
|
|
{
|
|
wc = ((cu1 & 0x0F) << 12)
|
|
+ ((cu2 & 0x3F) << 6)
|
|
+ (c8 & 0x3F);
|
|
}
|
|
else
|
|
{
|
|
char8_t cu3 = ps->__value.__wchb[2];
|
|
wc = ((cu1 & 0x07) << 18)
|
|
+ ((cu2 & 0x3F) << 12)
|
|
+ ((cu3 & 0x3F) << 6)
|
|
+ (c8 & 0x3F);
|
|
}
|
|
}
|
|
ps->__count &= 0x7fffffff;
|
|
ps->__value.__wch = 0;
|
|
}
|
|
|
|
return wcrtomb (s, wc, ps);
|
|
}
|