str2ip.c

来自「一款类linux的操作系统源码」· C语言 代码 · 共 60 行

/*
 *  Roadrunner/pk
 *    Copyright (C) 1989-2002  Cornfed Systems, Inc.
 *
 *  The Roadrunner/pk operating system is free software; you can
 *  redistribute and/or modify it under the terms of the GNU General
 *  Public License, version 2, as published by the Free Software
 *  Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT 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
 *
 *  More information about the Roadrunner/pk operating system of
 *  which this file is a part is available on the World-Wide Web
 *  at: http://www.cornfed.com.
 *
 */

#include <errno.h>
#include <net/ip.h>
#include <sys/lex.h>

int
str2ip(char *s, ipaddr * ip)
{
    struct lex l;
    int pos = 0, i;

    *ip = 0;

    nextlex(s, &pos, &l);
    if (l.type != LEX_NUM) {
	*ip = 0;
	return EFAIL;
    }
    *ip = (ipaddr) l.val;

    for (i = 0; i < 3; i++) {
	nextlex(s, &pos, &l);
	if (l.type != LEX_PERIOD) {
	    *ip = 0;
	    return EFAIL;
	}
	nextlex(s, &pos, &l);
	if (l.type != LEX_NUM) {
	    *ip = 0;
	    return EFAIL;
	}
	*ip = ((*ip) << 8) + (ipaddr) l.val;
    }
    return 0;
}