67 lines
1.8 KiB
C
67 lines
1.8 KiB
C
/*
|
|
FUNCTION
|
|
<<_mblen_r>>---reentrant minimal multibyte length function
|
|
|
|
INDEX
|
|
_mblen_r
|
|
|
|
ANSI_SYNOPSIS
|
|
#include <stdlib.h>
|
|
int _mblen_r(struct _reent *<[r]>, const char *<[s]>, size_t <[n]>, int *<[state]>);
|
|
|
|
TRAD_SYNOPSIS
|
|
#include <stdlib.h>
|
|
int _mblen_r(<[r]>, <[s]>, <[n]>, <[state]>)
|
|
struct _reent *<[r]>;
|
|
const char *<[s]>;
|
|
size_t <[n]>;
|
|
int *<[state]>;
|
|
|
|
DESCRIPTION
|
|
When MB_CAPABLE is not defined, this is a minimal ANSI-conforming
|
|
implementation of <<_mblen_r>>. In this case, the
|
|
only ``multi-byte character sequences'' recognized are single bytes,
|
|
and thus <<1>> is returned unless <[s]> is the null pointer or
|
|
has a length of 0 or is the empty string.
|
|
|
|
When MB_CAPABLE is defined, this routine calls <<_mbtowc_r>> to perform
|
|
the conversion, passing a state variable to allow state dependent
|
|
decoding. The result is based on the locale setting which may
|
|
be restricted to a defined set of locales.
|
|
|
|
RETURNS
|
|
This implementation of <<_mblen_r>> returns <<0>> if
|
|
<[s]> is <<NULL>> or the empty string; it returns <<1>> if not MB_CAPABLE or
|
|
the character is a single-byte character; it returns <<-1>>
|
|
if the multi-byte character is invalid; otherwise it returns
|
|
the number of bytes in the multibyte character.
|
|
|
|
PORTABILITY
|
|
<<_mblen>> is required in the ANSI C standard. However, the precise
|
|
effects vary with the locale.
|
|
|
|
<<_mblen_r>> requires no supporting OS subroutines.
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
|
|
int
|
|
_DEFUN (_mblen_r, (r, s, n, state),
|
|
struct _reent *r _AND
|
|
const char *s _AND
|
|
size_t n _AND
|
|
int *state)
|
|
{
|
|
#ifdef MB_CAPABLE
|
|
|
|
return _mbtowc_r (r, NULL, s, n, state);
|
|
#else /* not MB_CAPABLE */
|
|
if (s == NULL || *s == '\0')
|
|
return 0;
|
|
if (n == 0)
|
|
return -1;
|
|
return 1;
|
|
#endif /* not MB_CAPABLE */
|
|
}
|
|
|