Source: ../../contrib/olsr/twohop.hh
|
|
|
|
// -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*-
// vim:set sts=4 ts=8 sw=4:
// Copyright (c) 2001-2008 XORP, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software")
// to deal in the Software without restriction, subject to the conditions
// listed in the XORP LICENSE file. These conditions include: you must
// preserve this copyright notice, and you cannot mention the copyright
// holders in advertising related to the Software without their permission.
// The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This
// notice is a summary of the XORP LICENSE file; the license in that file is
// legally binding.
// $XORP: xorp/contrib/olsr/twohop.hh,v 1.2 2008/07/23 05:09:53 pavlin Exp $
#ifndef __OLSR_TWOHOP_HH__
#define __OLSR_TWOHOP_HH__
class Neighbor;
class Neighborhood;
// From now on, N1 is shorthand for "one-hop neighbor", and
// N2 is shorthand for "two-hop neighbor".
/**
* @short A two-hop neighbor.
*
* When the last link expires, the entire instance expires.
*/
class TwoHopNeighbor {
public:
TwoHopNeighbor(EventLoop& ev,
Neighborhood* parent,
const OlsrTypes::TwoHopNodeID id,
const IPv4& main_addr,
const OlsrTypes::TwoHopLinkID tlid);
inline OlsrTypes::TwoHopNodeID id() const { return _id; }
inline IPv4 main_addr() const { return _main_addr; }
/**
* Associate this N2 with an N1, using an instance of
* the association class TwoHopLink.
*
* @param tlid the ID of a two-hop link.
*/
void add_twohop_link(const OlsrTypes::TwoHopLinkID tlid);
/**
* Delete the given N1 from the set of Neighbors which may
* be used to reach this N2.
*
* @param tlid the ID of a two-hop link.
* @return true if the last link to the TwoHopNeighbor was removed.
*/
bool delete_twohop_link(const OlsrTypes::TwoHopLinkID tlid);
size_t delete_all_twohop_links();
inline const set<OlsrTypes::TwoHopLinkID>& twohop_links() const {
return _twohop_links;
}
/**
* Add the given neighbor as an MPR which covers this node.
*
* @param nid the N to count as one of this N2's covering nodes.
*/
void add_covering_mpr(const OlsrTypes::NeighborID nid);
/**
* Withdraw the given neighbor as an MPR which covers this node.
*
* @param nid the N to count as one of this N2's covering nodes.
*/
void withdraw_covering_mpr(const OlsrTypes::NeighborID nid);
/**
* Reset the MPR coverage state for this N2 node.
*/
void reset_covering_mprs();
/**
* @return The number of MPRs which cover this node.
*/
inline uint32_t coverage() const { return _coverage; }
/**
* @return true if this N2 is covered by at least N1.
*/
inline bool is_covered() const { return _coverage > 0; }
/**
* @return The number of MPR candidates which cover this node.
* This is not computed here but by Neighborhood, the parent.
* Note: This is NOT the same as a neighbor's reachability.
*/
inline uint32_t reachability() const { return _reachability; }
/**
* Set this N2's reachability.
*/
inline void set_reachability(uint32_t value) { _reachability = value; }
/**
* @return true if this N2 is reachable.
*/
inline bool is_reachable() const { return _reachability > 0; }
/**
* @return true if this N2 is strict.
*
* An N2 is strict if it appears only in the
* two-hop neighborhood, and not in the one-hop neighborhood.
*/
bool is_strict() const { return _is_strict; }
/**
* Set if this N2 is a strict two-hop neighbor.
*
* @param is_strict true if this N2 does NOT also appear as an N1.
*/
void set_is_strict(bool is_strict) {
_is_strict = is_strict;
}
/**
* @return the set of two-hop links pointing to this N2 node.
*/
const set<OlsrTypes::TwoHopLinkID>& twohop_links() {
return _twohop_links;
}
private:
EventLoop& _ev;
Neighborhood* _parent;
/**
* Unique ID of this N2 node.
*/
OlsrTypes::TwoHopNodeID _id;
/**
* N_2hop_addr protocol variable.
* Main protocol address of this N2 node.
*/
IPv4 _main_addr;
/**
* true if this N2 is NOT also an N1 node.
*/
bool _is_strict;
/**
* The number of strict N1 which can
* reach this strict N2, and which have been
* selected as MPRs by the Neighborhood.
*/
uint32_t _coverage;
/**
* The number of strict N1 which can reach this strict N2.
*/
uint32_t _reachability;
/**
* Links by which this two-hop neighbor is reachable.
*/
set<OlsrTypes::TwoHopLinkID> _twohop_links;
};
/**
* @short A link between a Neighbor and a TwoHopNeighbor.
*
* Association class between TwoHopNeighbor and Neighbor.
* TwoHopNeighbor cannot exist without TwoHopLink. Like Link and Neighbor,
* there is a co-dependent relationship. Both TwoHopNeighbor and TwoHopLink
* cannot exist without Neighbor.
*
* TwoHopLinks are uniquely identified by the ID of the two-hop neighbor
* at the far end, and the Neighbor at the near end. When the last
* TwoHopLink associated with a TwoHopNeighbor is deleted, the
* TwoHopNeighbor MUST be deleted, to conform to the relations in the RFC.
*/
class TwoHopLink {
public:
TwoHopLink(EventLoop& ev, Neighborhood* parent,
OlsrTypes::TwoHopLinkID tlid,
Neighbor* nexthop, const TimeVal& vtime);
/**
* @return A unique identifier for this link in the two-hop
* neighborhood.
*/
inline OlsrTypes::TwoHopLinkID id() const { return _id; }
/**
* @return A pointer to the strict one-hop neighbor at the
* near end of this link.
*/
inline Neighbor* nexthop() const { return _nexthop; }
/**
* @return A pointer to the strict two-hop neighbor at the
* far end of this link.
*/
inline TwoHopNeighbor* destination() const {
XLOG_ASSERT(0 != _destination); // Catch programming errors.
return _destination;
}
/**
* Set the cached destination pointer.
*
* @param destination the TwoHopNeighbor at the end of this link.
*/
inline void set_destination(TwoHopNeighbor* destination) {
// Invariant: set_destination() should only be called once,
// immediately after the TwoHopLink has been created, to
// associate it with a TwoHopNeighbor.
XLOG_ASSERT(0 == _destination);
_destination = destination;
}
/**
* @return The ID of the interface where the advertisement of this
* TwoHopLink was last heard by a Neighbor.
*/
inline OlsrTypes::FaceID face_id() const { return _face_id; }
/**
* @return ETX measurement at near end of link.
*/
inline double near_etx() const { return _near_etx; }
/**
* @return ETX measurement at far end of link.
*/
inline double far_etx() const { return _far_etx; }
/**
* Set the ID of the interface where this link was last heard.
*
* @param faceid the ID of the interface.
*/
inline void set_face_id(const OlsrTypes::FaceID faceid) {
_face_id = faceid;
}
/**
* Set the ETX measurement at near end of link.
*
* @param near_etx near end ETX measurement.
*/
inline void set_near_etx(const double& near_etx) {
_near_etx = near_etx;
}
/**
* Set the ETX measurement at far end of link.
*
* @param far_etx far end ETX measurement.
*/
inline void set_far_etx(const double& far_etx) {
_far_etx = far_etx;
}
/**
* @return the amount of time remaining until this two-hop link expires.
*/
inline TimeVal time_remaining() const {
TimeVal tv;
_expiry_timer.time_remaining(tv);
return tv;
}
/**
* Update this link's expiry timer.
*
* @param vtime the amount of time from now til when the link expires.
*/
void update_timer(const TimeVal& vtime);
/**
* Callback method to: tell the parent that this two-hop link
* has now expired.
*/
void event_dead();
private:
EventLoop& _ev;
Neighborhood* _parent;
/**
* A unique identifier for this object.
*/
OlsrTypes::TwoHopLinkID _id;
/**
* The strict one-hop neighbor used to reach the two-hop neighbor
* referenced by _far_id.
*/
Neighbor* _nexthop;
/**
* The two-hop neighbor at the end of this link.
*/
TwoHopNeighbor* _destination;
/**
* The ID of the interface where the advertisement of this link
* was last heard.
*/
OlsrTypes::FaceID _face_id;
/**
* The time at which this two-hop link expires.
*/
XorpTimer _expiry_timer;
/**
* The ETX as measured at the near end of this link. Optional.
*/
double _near_etx;
/**
* The ETX as measured at the far end of this link. Optional.
*/
double _far_etx;
};
#endif // __OLSR_TWOHOP_HH__
Generated by: bms on anglepoise.lon.incunabulum.net on Wed Jul 23 10:06:13 2008, using kdoc 2.0a54+XORP.
