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/* Copyright (C) 1993, 1995-1997, 2002-2003, 2005-2007, 2009-2015 Free Software
* Foundation, Inc.
NOTE: The canonical source of this file is maintained with the GNU C Library.
Bugs can be reported to bug-glibc@gnu.org.
This program is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or any
later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* This is almost copied from strncpy.c, written by Torbjorn Granlund. */
#include <config.h>
/* Specification. */
#include <string.h>
#ifndef weak_alias
# define __stpncpy stpncpy
#endif
/* Copy no more than N bytes of SRC to DST, returning a pointer past the
last non-NUL byte written into DST. */
char *
(__stpncpy) (char *dest, const char *src, size_t n)
{
char c;
char *s = dest;
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;
}
#ifdef weak_alias
weak_alias (__stpncpy, stpncpy)
#endif
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