newlib-cygwin/newlib/libc/stdlib/wcsnrtombs.c

168 lines
3.9 KiB
C

/*
FUNCTION
<<wcsrtombs>>, <<wcsnrtombs>>---convert a wide-character string to a character string
INDEX
wcsrtombs
INDEX
_wcsrtombs_r
INDEX
wcsnrtombs
INDEX
_wcsnrtombs_r
SYNOPSIS
#include <wchar.h>
size_t wcsrtombs(char *__restrict <[dst]>,
const wchar_t **__restrict <[src]>, size_t <[len]>,
mbstate_t *__restrict <[ps]>);
#include <wchar.h>
size_t _wcsrtombs_r(struct _reent *<[ptr]>, char *<[dst]>,
const wchar_t **<[src]>, size_t <[len]>,
mbstate_t *<[ps]>);
#include <wchar.h>
size_t wcsnrtombs(char *__restrict <[dst]>,
const wchar_t **__restrict <[src]>,
size_t <[nwc]>, size_t <[len]>,
mbstate_t *__restrict <[ps]>);
#include <wchar.h>
size_t _wcsnrtombs_r(struct _reent *<[ptr]>, char *<[dst]>,
const wchar_t **<[src]>, size_t <[nwc]>,
size_t <[len]>, mbstate_t *<[ps]>);
DESCRIPTION
The <<wcsrtombs>> function converts a string of wide characters indirectly
pointed to by <[src]> to a corresponding multibyte character string stored in
the array pointed to by <[dst]>. No more than <[len]> bytes are written to
<[dst]>.
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, <<wcsrtombs>> uses an internal, static mbstate_t object, which
is initialized to the initial conversion state at program startup.
The <<wcsnrtombs>> function behaves identically to <<wcsrtombs>>, except that
conversion stops after reading at most <[nwc]> characters from the buffer
pointed to by <[src]>.
RETURNS
The <<wcsrtombs>> and <<wcsnrtombs>> functions return the number of bytes
stored in the array pointed to by <[dst]> (not including any terminating
null), if successful, otherwise it returns (size_t)-1.
PORTABILITY
<<wcsrtombs>> is defined by C99 standard.
<<wcsnrtombs>> 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>
#include "local.h"
#include "../locale/setlocale.h"
#ifdef _REENT_THREAD_LOCAL
_Thread_local _mbstate_t _tls_wcsrtombs_state;
#endif
size_t
_wcsnrtombs_l (struct _reent *r, char *dst, const wchar_t **src, size_t nwc,
size_t len, mbstate_t *ps, struct __locale_t *loc)
{
char *ptr = dst;
char buff[10];
wchar_t *pwcs;
size_t n;
int i;
#ifdef _MB_CAPABLE
if (ps == NULL)
{
_REENT_CHECK_MISC(r);
ps = &(_REENT_WCSRTOMBS_STATE(r));
}
#endif
/* If no dst pointer, treat len as maximum possible value. */
if (dst == NULL)
len = (size_t)-1;
n = 0;
pwcs = (wchar_t *)(*src);
while (n < len && nwc-- > 0)
{
int count = ps->__count;
wint_t wch = ps->__value.__wch;
int bytes = loc->wctomb (r, buff, *pwcs, ps);
if (bytes == -1)
{
_REENT_ERRNO(r) = EILSEQ;
ps->__count = 0;
return (size_t)-1;
}
if (n + bytes <= len)
{
n += bytes;
if (dst)
{
for (i = 0; i < bytes; ++i)
*ptr++ = buff[i];
++(*src);
}
if (*pwcs++ == 0x00)
{
if (dst)
*src = NULL;
ps->__count = 0;
return n - 1;
}
}
else
{
/* not enough room, we must back up state to before __WCTOMB call */
ps->__count = count;
ps->__value.__wch = wch;
len = 0;
}
}
return n;
}
size_t
_wcsnrtombs_r (struct _reent *r,
char *dst,
const wchar_t **src,
size_t nwc,
size_t len,
mbstate_t *ps)
{
return _wcsnrtombs_l (_REENT, dst, src, nwc, len, ps,
__get_current_locale ());
}
#ifndef _REENT_ONLY
size_t
wcsnrtombs (char *__restrict dst,
const wchar_t **__restrict src,
size_t nwc,
size_t len,
mbstate_t *__restrict ps)
{
return _wcsnrtombs_l (_REENT, dst, src, nwc, len, ps,
__get_current_locale ());
}
#endif /* !_REENT_ONLY */