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/* Copyright (c) 2007 Corinna Vinschen <corinna@vinschen.de> */
/*
FUNCTION
<<wcpncpy>>---copy part of a wide-character string returning a pointer to its end
SYNOPSIS
#include <wchar.h>
wchar_t *wcpncpy(wchar_t *__restrict <[s1]>,
const wchar_t *__restrict <[s2]>, size_t <[n]>);
DESCRIPTION
The <<wcpncpy>> function copies not more than n wide-character codes
(wide-character codes that follow a null wide-character code are not
copied) from the array pointed to by <[s2]> to the array pointed to
by <[s1]>. If copying takes place between objects that overlap, the
behaviour is undefined.
If the array pointed to by <[s2]> is a wide-character string that is
shorter than <[n]> wide-character codes, null wide-character codes are
appended to the copy in the array pointed to by <[s1]>, until <[n]>
wide-character codes in all are written.
RETURNS
The <<wcpncpy>> function returns <[s1]>; no return value is reserved to
indicate an error.
PORTABILITY
<<wcpncpy>> is ISO/IEC 9899/AMD1:1995 (ISO C).
No supporting OS subroutines are required.
*/
#define _DEFAULT_SOURCE
#include <wchar.h>
wchar_t *
wcpncpy(wchar_t * __restrict dst, const wchar_t * __restrict src, size_t count)
{
wchar_t *ret = NULL;
while (count > 0) {
--count;
if ((*dst++ = *src++) == L'\0') {
ret = dst - 1;
break;
}
}
while (count-- > 0)
*dst++ = L'\0';
return ret ? ret : dst;
}