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/* Copyright (C) 1993,1995,1996,1997,2002,2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* This is almost copied from strncpy.c, written by Torbjorn Granlund. */
#include <string.h>
/* Copy no more than N characters of SRC to DEST, returning the address of
the terminating '\0' in DEST, if any, or else DEST + N. */
char *
__stpncpy_chk (char *dest, const char *src, size_t n, size_t destlen)
{
char c;
char *s = dest;
if (__builtin_expect (destlen < n, 0))
__chk_fail ();
if (n >= 4)
{
size_t n4 = n >> 2;
for (;;)
{
c = *src++;
*dest++ = c;
if (c == '\0')
break;
c = *src++;
*dest++ = c;
if (c == '\0')
break;
c = *src++;
*dest++ = c;
if (c == '\0')
break;
c = *src++;
*dest++ = c;
if (c == '\0')
break;
if (--n4 == 0)
goto last_chars;
}
n -= dest - s;
goto zero_fill;
}
last_chars:
n &= 3;
if (n == 0)
return dest;
for (;;)
{
c = *src++;
--n;
*dest++ = c;
if (c == '\0')
break;
if (n == 0)
return dest;
}
zero_fill:
while (n-- > 0)
dest[n] = '\0';
return dest - 1;
}
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