// -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*-

// Copyright (c) 2001-2009 XORP, Inc.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License, Version 2, June
// 1991 as published by the Free Software Foundation. Redistribution
// and/or modification of this program under the terms of any other
// version of the GNU General Public License is not permitted.
// 
// This program 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. For more details,
// see the GNU General Public License, Version 2, a copy of which can be
// found in the XORP LICENSE.gpl file.
// 
// XORP Inc, 2953 Bunker Hill Lane, Suite 204, Santa Clara, CA 95054, USA;
// http://xorp.net

// $XORP: xorp/bgp/update_attrib.hh,v 1.16 2008/10/02 21:56:23 bms Exp $

#ifndef __BGP_UPDATE_ATTRIB_HH__
#define __BGP_UPDATE_ATTRIB_HH__

#include "libxorp/ipvxnet.hh"
#include "libxorp/exceptions.hh"
#include "exceptions.hh"
#include <list>

/**
 * Encoding used in BGP update packets to encode prefixes
 * (IPv4 only) for withdrawn routes and NLRI information.
 *
 * The prefixes are passed on the wire in a compressed format:
 *   1 byte:	prefix length L (in bits)
 *   n bytes:	prefix, L bits (n = (L+7)/8)
 *
 * Effectively, this class is just an IPv4Net.
 * We only need methods to encode and decode the objects.
 */
class BGPUpdateAttrib : public IPv4Net
{
public:
    /**
     * construct from an address d and mask length s
     */
    BGPUpdateAttrib(const IPv4& d, uint8_t s) : IPv4Net(d, s) {}

    BGPUpdateAttrib(const IPv4Net& p) : IPv4Net(p)		{}

    /**
     * Construct from wire format
     */
    BGPUpdateAttrib(const uint8_t *d);

    /**
     * store in memory in wire format
     */
    void copy_out(uint8_t *d) const;

    /**
     * total size in encoded format
     */
    size_t wire_size() const					{
	return calc_byte_size() + 1;
    }

    // size of next operand in memory
    static size_t size(const uint8_t *d) throw(CorruptMessage);

    size_t calc_byte_size() const			{
	return (prefix_len() + 7) / 8;
    }

    const IPv4Net& net() const				{
	return (IPv4Net &)(*this);
    }

    string str(string nlri_or_withdraw) const				{
	return nlri_or_withdraw + " " + net().str();
    }

protected:
private:
};


class BGPUpdateAttribList : public list <BGPUpdateAttrib> {
public:
    typedef list <BGPUpdateAttrib>::const_iterator const_iterator;
    typedef list <BGPUpdateAttrib>::iterator iterator;

    size_t wire_size() const;
    uint8_t *encode(size_t &l, uint8_t *buf = 0) const;
    void decode(const uint8_t *d, size_t len)
	throw(CorruptMessage);
    string str(string) const;

    // XXX this needs to be fixed, we do not want to sort all the times.
    bool operator== (const BGPUpdateAttribList& other)	{
	if (size() != other.size())
	    return false;
        BGPUpdateAttribList me(*this);
        BGPUpdateAttribList him(other);
	me.sort();
	him.sort();
 	const_iterator i, j;
	// only check one iterator as we know length is the same
	for (i=me.begin(), j=him.begin(); i!=me.end(); ++i, ++j)
	    if ( *i != *j )
		return false;
	return true;
    }
};

#endif // __BGP_UPDATE_ATTRIB_HH__
