grub/grub-core/gnulib/mbsinit.c
Vladimir 'phcoder' Serbinenko 053cfcddf1 Import new gnulib.
2013-04-11 21:12:46 +02:00

61 lines
1.9 KiB
C

/* Test for initial conversion state.
Copyright (C) 2008-2013 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2008.
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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */
#include <config.h>
/* Specification. */
#include <wchar.h>
#include "verify.h"
#if (defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__
/* On native Windows, 'mbstate_t' is defined as 'int'. */
int
mbsinit (const mbstate_t *ps)
{
return ps == NULL || *ps == 0;
}
#else
/* Platforms that lack mbsinit() also lack mbrlen(), mbrtowc(), mbsrtowcs()
and wcrtomb(), wcsrtombs().
We assume that
- sizeof (mbstate_t) >= 4,
- only stateless encodings are supported (such as UTF-8 and EUC-JP, but
not ISO-2022 variants),
- for each encoding, the number of bytes for a wide character is <= 4.
(This maximum is attained for UTF-8, GB18030, EUC-TW.)
We define the meaning of mbstate_t as follows:
- In mb -> wc direction, mbstate_t's first byte contains the number of
buffered bytes (in the range 0..3), followed by up to 3 buffered bytes.
- In wc -> mb direction, mbstate_t contains no information. In other
words, it is always in the initial state. */
verify (sizeof (mbstate_t) >= 4);
int
mbsinit (const mbstate_t *ps)
{
const char *pstate = (const char *)ps;
return pstate == NULL || pstate[0] == 0;
}
#endif