newlib/winsup/mingw/mingwex/wmemmove.c

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/* This source code was extracted from the Q8 package created and placed
in the PUBLIC DOMAIN by Doug Gwyn <gwyn@arl.mil>
last edit: 1999/11/05 gwyn@arl.mil
Implements subclause 7.24 of ISO/IEC 9899:1999 (E).
It supports an encoding where all char codes are mapped
to the *same* code values within a wchar_t or wint_t,
so long as no other wchar_t codes are used by the program.
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <wchar.h>
wchar_t *
wmemmove(s1, s2, n)
register wchar_t *s1;
register const wchar_t *s2;
register size_t n;
{
wchar_t *orig_s1 = s1;
if ( s1 == NULL || s2 == NULL || n == 0 )
return orig_s1; /* robust */
/* XXX -- The following test works only within a flat address space! */
if ( s2 >= s1 )
for ( ; n > 0; --n )
*s1++ = *s2++;
else {
s1 += n;
s2 += n;
for ( ; n > 0; --n )
*--s1 = *--s2;
}
return orig_s1;
}