strongswan/src/libfreeswan/subnetof.c

59 lines
1.4 KiB
C

/*
* minor network-address manipulation utilities
* Copyright (C) 1998, 1999 Henry Spencer.
*
* This 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. See <http://www.fsf.org/copyleft/lgpl.txt>.
*
* This 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.
*/
#include "internal.h"
#include "freeswan.h"
/*
- subnetof - given address and mask, return subnet part
*/
struct in_addr
subnetof(addr, mask)
struct in_addr addr;
struct in_addr mask;
{
struct in_addr result;
result.s_addr = addr.s_addr & mask.s_addr;
return result;
}
/*
- hostof - given address and mask, return host part
*/
struct in_addr
hostof(addr, mask)
struct in_addr addr;
struct in_addr mask;
{
struct in_addr result;
result.s_addr = addr.s_addr & ~mask.s_addr;
return result;
}
/*
- broadcastof - given (network) address and mask, return broadcast address
*/
struct in_addr
broadcastof(addr, mask)
struct in_addr addr;
struct in_addr mask;
{
struct in_addr result;
result.s_addr = addr.s_addr | ~mask.s_addr;
return result;
}