OpenBSD-4.6/usr.bin/sup/src/snprintf.c

/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Chris Torek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char rcsid[] = "$OpenBSD: snprintf.c,v 1.3 2003/06/03 02:56:17 millert Exp $";
#endif /* LIBC_SCCS and not lint */

#include <stdio.h>
#include <stdarg.h>

#ifdef _IOSTRG
#define STRFLAG		(_IOSTRG|_IOWRT)	/* no _IOWRT: avoid stdio bug */
#else
#define STRFLAG		(_IOREAD)		/* XXX: Assume svr4 stdio */
#endif

#ifdef NEED_SNPRINTF
snprintf(char *str, size_t n, char const *fmt, ...)
{
	int ret;
	va_list ap;
	FILE f;

	if ((int)n < 1)
		return (EOF);
	va_start(ap, fmt);
	f._flag = STRFLAG;
	f._base = f._ptr = str;
	f._cnt = n-1;
	f._file = -1; 
	_doprnt(fmt, ap, &f);
	f._cnt++;
	putc('\0', &f);
	if (f._cnt<0)
	    f._cnt = 0;
	va_end(ap);
	return(n-f._cnt-1);
}
#endif /* NEED_SNPRINTF */