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/* Copyright (C) 1993, 1995, 1996 Free Software Foundation, Inc.
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, or (at your option)
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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* This is almost copied from strncpy.c, written by Torbjorn Granlund. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <sys/types.h>
/* Copy no more than N characters of SRC to DEST, returning the address of
the last character written into DEST. */
char *
stpncpy (dest, src, n)
char *dest;
const char *src;
size_t n;
{
char c;
char *s = dest;
--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 = n - (dest - s) - 1;
if (n == 0)
return dest + 1;
goto zero_fill;
}
last_chars:
n &= 3;
if (n == 0)
return dest + 1;
do
{
c = *src++;
*++dest = c;
if (--n == 0)
return dest + 1;
}
while (c != '\0');
zero_fill:
while (n-- > 0)
dest[n] = '\0';
return dest;
}
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