xref: /illumos-gate/usr/src/contrib/ast/src/lib/libast/string/strncopy.c (revision b30d1939)

/***********************************************************************
*                                                                      *
*               This software is part of the ast package               *
*          Copyright (c) 1985-2011 AT&T Intellectual Property          *
*                      and is licensed under the                       *
*                 Eclipse Public License, Version 1.0                  *
*                    by AT&T Intellectual Property                     *
*                                                                      *
*                A copy of the License is available at                 *
*          http://www.eclipse.org/org/documents/epl-v10.html           *
*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
*                                                                      *
*              Information and Software Systems Research               *
*                            AT&T Research                             *
*                           Florham Park NJ                            *
*                                                                      *
*                 Glenn Fowler <gsf@research.att.com>                  *
*                  David Korn <dgk@research.att.com>                   *
*                   Phong Vo <kpv@research.att.com>                    *
*                                                                      *
***********************************************************************/
#pragma prototyped

#include <ast.h>

/*
 * copy up to n bytes of string f into t
 * trailing 0 always added to t, even if n==0
 * pointer to the copied 0 returned
 */

char*
strncopy(register char* t, register const char* f, size_t n)
{
	register char*	e = t + n - 1;

	do
	{
		if (t >= e)
		{
			*t = 0;
			return t;
		}
	} while (*t++ = *f++);
	return t - 1;
}