libc/newlib/libc/stdlib/mbsnrtowcs.c

148 lines
3.4 KiB
C

/*
FUNCTION
<<mbsrtowcs>>, <<mbsnrtowcs>>---convert a character string to a wide-character string
INDEX
mbsrtowcs
INDEX
_mbsrtowcs_r
INDEX
mbsnrtowcs
INDEX
_mbsnrtowcs_r
SYNOPSIS
#include <wchar.h>
size_t mbsrtowcs(wchar_t *__restrict <[dst]>,
const char **__restrict <[src]>,
size_t <[len]>,
mbstate_t *__restrict <[ps]>);
#include <wchar.h>
size_t _mbsrtowcs_r(struct _reent *<[ptr]>, wchar_t *<[dst]>,
const char **<[src]>, size_t <[len]>,
mbstate_t *<[ps]>);
#include <wchar.h>
size_t mbsnrtowcs(wchar_t *__ restrict <[dst]>,
const char **__restrict <[src]>, size_t <[nms]>,
size_t <[len]>, mbstate_t *__restrict <[ps]>);
#include <wchar.h>
size_t _mbsnrtowcs_r(struct _reent *<[ptr]>, wchar_t *<[dst]>,
const char **<[src]>, size_t <[nms]>,
size_t <[len]>, mbstate_t *<[ps]>);
DESCRIPTION
The <<mbsrtowcs>> function converts a sequence of multibyte characters
pointed to indirectly by <[src]> into a sequence of corresponding wide
characters and stores at most <[len]> of them in the wchar_t array pointed
to by <[dst]>, until it encounters a terminating null character ('\0').
If <[dst]> is NULL, no characters are stored.
If <[dst]> is not NULL, the pointer pointed to by <[src]> is updated to point
to the character after the one that conversion stopped at. If conversion
stops because a null character is encountered, *<[src]> is set to NULL.
The mbstate_t argument, <[ps]>, is used to keep track of the shift state. If
it is NULL, <<mbsrtowcs>> uses an internal, static mbstate_t object, which
is initialized to the initial conversion state at program startup.
The <<mbsnrtowcs>> function behaves identically to <<mbsrtowcs>>, except that
conversion stops after reading at most <[nms]> bytes from the buffer pointed
to by <[src]>.
RETURNS
The <<mbsrtowcs>> and <<mbsnrtowcs>> functions return the number of wide
characters stored in the array pointed to by <[dst]> if successful, otherwise
it returns (size_t)-1.
PORTABILITY
<<mbsrtowcs>> is defined by the C99 standard.
<<mbsnrtowcs>> is defined by the POSIX.1-2008 standard.
*/
#include <reent.h>
#include <newlib.h>
#include <wchar.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
size_t
_mbsnrtowcs_r (struct _reent *r,
wchar_t *dst,
const char **src,
size_t nms,
size_t len,
mbstate_t *ps)
{
wchar_t *ptr = dst;
const char *tmp_src;
size_t max;
size_t count = 0;
int bytes;
#ifdef _MB_CAPABLE
if (ps == NULL)
{
_REENT_CHECK_MISC(r);
ps = &(_REENT_MBSRTOWCS_STATE(r));
}
#endif
if (dst == NULL)
{
/* Ignore original len value and do not alter src pointer if the
dst pointer is NULL. */
len = (size_t)-1;
tmp_src = *src;
src = &tmp_src;
}
max = len;
while (len > 0)
{
bytes = _mbrtowc_r (r, ptr, *src, nms, ps);
if (bytes > 0)
{
*src += bytes;
nms -= bytes;
++count;
ptr = (dst == NULL) ? NULL : ptr + 1;
--len;
}
else if (bytes == -2)
{
*src += nms;
return count;
}
else if (bytes == 0)
{
*src = NULL;
return count;
}
else
{
ps->__count = 0;
r->_errno = EILSEQ;
return (size_t)-1;
}
}
return (size_t)max;
}
#ifndef _REENT_ONLY
size_t
mbsnrtowcs (wchar_t *__restrict dst,
const char **__restrict src,
size_t nms,
size_t len,
mbstate_t *__restrict ps)
{
return _mbsnrtowcs_r (_REENT, dst, src, nms, len, ps);
}
#endif /* !_REENT_ONLY */