incubator-nuttx/libs/libc/stdio/lib_fgetwc.c

124 lines
3.7 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_fgetwc.c
*
* SPDX-License-Identifier: MIT
* SPDX-FileCopyrightText: 2005-2014 Rich Felker, et al.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <wchar.h>
#include <errno.h>
#include <string.h>
#ifdef CONFIG_FILE_STREAM
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: fgetwc_unlocked
*
* Description:
* Get wide character from stream without lock the stream
*
* Input Parameters:
* f - Pointer to a FILE object that identifies an input stream, during
* the read operaiton, the stream will not be locked
*
* Returned Value:
* Return the character read is returned,
* Return WEOF is the sequence of bytes that read cannot be interpreted as
* a valid wide characted, and sets the errno to EILSEQ
*
****************************************************************************/
wint_t fgetwc_unlocked(FAR FILE *f)
{
mbstate_t st;
wchar_t wc;
int c;
char b;
size_t l = -2;
memset(&st, 0, sizeof(mbstate_t));
/* Convert character byte-by-byte */
while (l == -2)
{
c = getc_unlocked(f);
b = (char)c;
if (c < 0)
{
if (!mbsinit(&st))
{
set_errno(EILSEQ);
}
f->fs_flags |= __FS_FLAG_EOF;
return WEOF;
}
l = mbrtowc(&wc, &b, 1, &st);
if (l == -1)
{
f->fs_flags |= __FS_FLAG_EOF;
return WEOF;
}
}
return wc;
}
/****************************************************************************
* Name: fgetwc
*
* Description:
* Get wide character from stream
*
* Input Parameters:
* f - Pointer to a FILE object that identifies an input stream, the stream
* will be locked during the read operation
*
* Returned Value:
* Return the character read is returned,
* Return WEOF is the sequence of bytes that read cannot be interpreted as
* a valid wide characted, and sets the errno to EILSEQ
*
****************************************************************************/
wint_t fgetwc(FAR FILE *f)
{
wint_t c;
flockfile(f);
c = fgetwc_unlocked(f);
funlockfile(f);
return c;
}
#endif /* CONFIG_FILE_STREAM */