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/* Copyright (C) 1993 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
/* This is almost copied from strncpy.c, written by Torbjorn Granlund. */
#include <ansidecl.h>
#include <string.h>
#include <memcopy.h>
/* Copy no more than N characters of SRC to DEST, returning the address of
the last character written into DEST. */
char *
DEFUN(__stpncpy, (dest, src, n), char *dest AND CONST char *src AND size_t n)
{
reg_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;
goto zero_fill;
}
last_chars:
n &= 3;
if (n == 0)
return s;
do
{
c = *src++;
*++dest = c;
if (--n == 0)
return dest;
}
while (c != '\0');
zero_fill:
do
*++dest = '\0';
while (--n > 0);
return dest;
}
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