/* *   OSPFD routing daemon *   Copyright (C) 1998 by John T. Moy *    *   This program is free software; you can redistribute it and/or *   modify it under the terms of the GNU General Public License *   as published by the Free Software Foundation; either version 2 *   of the License, or (at your option) any later version. *    *   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.  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. *//* Classes supporting iteration through various lists. * Good candidates for implementation via templates. *//* The Interface iterator class, used when walking down a list of interfaces. * Primitives provided to walk down the list, and to delete the * "current" list element (which may or may not be the list's * head. */class IfcIterator {    SpfIfc *next;	// Next list element    class SpfArea *area;    const class OSPF *inst;public:    inline IfcIterator(const class OSPF *);    inline IfcIterator(SpfArea *);    inline void reset();    inline SpfIfc *get_next();};inline IfcIterator::IfcIterator(const class OSPF *spf){    next = spf->ifcs;    area = 0;    inst = spf;}inline IfcIterator::IfcIterator(SpfArea *ap){    next = ap->a_ifcs;    area = ap;    inst = 0;}inline void IfcIterator::reset(){    if (area)	next = area->a_ifcs;    else	next = inst->ifcs;}inline SpfIfc *IfcIterator::get_next(){    SpfIfc *retval;    retval = next;    if (next)	next = (area ? next->anext : next->next);    return(retval);}/* The Neighbor iterator class. Similar to the above interface * iterator, only it's always per-interface. */class NbrIterator {    SpfNbr *next;	// Next list element    SpfIfc *ifc;	// Containing interfacepublic:    inline NbrIterator(SpfIfc *);    inline void reset();    inline SpfNbr *get_next();};inline NbrIterator::NbrIterator(SpfIfc *ip){    next = ip->if_nlst;    ifc = ip;}inline void NbrIterator::reset(){    next = ifc->if_nlst;}inline SpfNbr *NbrIterator::get_next(){    SpfNbr *retval;    retval = next;    if (next)	next = next->next;    return(retval);}/* The Area iterator class. */class AreaIterator {    SpfArea *next;	// Next list element    OSPF *inst;		// OSPF instancepublic:    inline AreaIterator(OSPF *);    inline SpfArea *get_next();};inline AreaIterator::AreaIterator(OSPF *instance){    next = instance->areas;    inst = instance;}inline SpfArea *AreaIterator::get_next(){    SpfArea *retval;    retval = next;    if (next)	next = next->next;    return(retval);}/* Iterate through all MD5 keys belonging to an interface. */class KeyIterator {    CryptK *next;	// Next list element    SpfIfc *ifc;	// Containing interfacepublic:    inline KeyIterator(SpfIfc *);    inline CryptK *get_next();};inline KeyIterator::KeyIterator(SpfIfc *ip){    next = ip->if_keys;    ifc = ip;}inline CryptK *KeyIterator::get_next(){    CryptK *retval;    retval = next;    if (next)	next = next->link;    return(retval);}