libc/newlib/libc/string/strxfrm_l.c

72 lines
1.8 KiB
C

/*
FUNCTION
<<strxfrm_l>>---transform string
INDEX
strxfrm_l
SYNOPSIS
#include <string.h>
size_t strxfrm_l(char *restrict <[s1]>, const char *restrict <[s2]>,
size_t <[n]>, locale_t <[locale]>);
DESCRIPTION
This function transforms the string pointed to by <[s2]> and
places the resulting string into the array pointed to by
<[s1]>. The transformation is such that if the <<strcmp>>
function is applied to the two transformed strings, it returns
a value greater than, equal to, or less than zero,
correspoinding to the result of a <<strcoll>> function applied
to the same two original strings.
No more than <[n]> characters are placed into the resulting
array pointed to by <[s1]>, including the terminating null
character. If <[n]> is zero, <[s1]> may be a null pointer. If
copying takes place between objects that overlap, the behavior
is undefined.
(NOT Cygwin:) The current implementation of <<strxfrm_l>> simply copies
the input and does not support any language-specific transformations.
If <[locale]> is LC_GLOBAL_LOCALE or not a valid locale object, the
behaviour is undefined.
RETURNS
The <<strxfrm_l>> function returns the length of the transformed string
(not including the terminating null character). If the value returned
is <[n]> or more, the contents of the array pointed to by
<[s1]> are indeterminate.
PORTABILITY
<<strxfrm_l>> is POSIX-1.2008.
<<strxfrm_l>> requires no supporting OS subroutines.
QUICKREF
strxfrm_l ansi pure
*/
#include <string.h>
size_t
strxfrm_l (char *__restrict s1, const char *__restrict s2, size_t n,
struct __locale_t *locale)
{
size_t res;
res = 0;
while (n-- > 0)
{
if ((*s1++ = *s2++) != '\0')
++res;
else
return res;
}
while (*s2)
{
++s2;
++res;
}
return res;
}