freebsd-skq/lib/libc/locale/mbrtoc16.c
ed 05bd8275f3 Add <uchar.h>.
The <uchar.h> header, part of C11, adds a small number of utility
functions for 16/32-bit "universal" characters, which may or may not be
UTF-16/32. As our wchar_t is already ISO 10646, simply add light-weight
wrappers around wcrtomb() and mbrtowc().

While there, also add (non-yet-standard) _l functions, similar to the
ones we already have for the other locale-dependent functions.

Reviewed by:	theraven
2013-05-21 19:59:37 +00:00

90 lines
2.8 KiB
C

/*-
* Copyright (c) 2013 Ed Schouten <ed@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <uchar.h>
#include "xlocale_private.h"
typedef struct {
char16_t trail_surrogate;
mbstate_t c32_mbstate;
} _Char16State;
size_t
mbrtoc16_l(char16_t * __restrict pc16, const char * __restrict s, size_t n,
mbstate_t * __restrict ps, locale_t locale)
{
_Char16State *cs;
char32_t c32;
ssize_t len;
FIX_LOCALE(locale);
if (ps == NULL)
ps = &locale->mbrtoc16;
cs = (_Char16State *)ps;
/*
* Call straight into mbrtoc32_l() if we don't need to return a
* character value. According to the spec, if s is a null
* pointer, the value of parameter pc16 is also ignored.
*/
if (pc16 == NULL || s == NULL) {
cs->trail_surrogate = 0;
return (mbrtoc32_l(NULL, s, n, &cs->c32_mbstate, locale));
}
/* Return the trail surrogate from the previous invocation. */
if (cs->trail_surrogate >= 0xdc00 && cs->trail_surrogate <= 0xdfff) {
*pc16 = cs->trail_surrogate;
cs->trail_surrogate = 0;
return ((size_t)-3);
}
len = mbrtoc32_l(&c32, s, n, &cs->c32_mbstate, locale);
if (len >= 0) {
if (c32 < 0x10000) {
/* Fits in one UTF-16 character. */
*pc16 = c32;
} else {
/* Split up in a surrogate pair. */
c32 -= 0x10000;
*pc16 = 0xd800 | (c32 >> 10);
cs->trail_surrogate = 0xdc00 | (c32 & 0x3ff);
}
}
return (len);
}
size_t
mbrtoc16(char16_t * __restrict pc16, const char * __restrict s, size_t n,
mbstate_t * __restrict ps)
{
return (mbrtoc16_l(pc16, s, n, ps, __get_locale()));
}