vos/corelibs/vos/typingtweaks/vobject.cc

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/*
    This file is part of the Virtual Object System of
    the Interreality project (http://interreality.org).

    Copyright (C) 2001, 2002 Peter Amstutz

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA

    Peter Amstutz <tetron@interreality.org>
*/
#include <stdio.h>
#include <signal.h>

#include <string>
#include <algorithm>
#include <typeinfo>

#include "vos.hh"

/** @file
    Implements VobjectImplementation.
*/

bool VobjectImplementation::queueMsgs_def=false;
bool VobjectImplementation::queueUpdateMsgs_def=false;

DoNothingListener DoNothingListener::static_;

bool Vobject::operator==(Vobject& v) {
    bool ret;
    rREF(Site&, ts, getSite(),
         rREF(Site&, vs, v.getSite(),
              ret = (((void*)&ts == (void*)&vs) && getName() == v.getName());
             );
        );
    return ret;
}

bool Vobject::operator==(Vobject* v) {
    bool ret;
    rREF(Site&, ts, getSite(),
         rREF(Site&, vs, v->getSite(),
              ret = (((void*)&ts == (void*)&vs) && getName() == v->getName());
             );
        );
    return ret;
}

VobjectImplementation::VobjectImplementation(const string& n, Site* s, bool islocalobj)
    :  islocal(islocalobj), exciseCalled(false), site(s), name(n),
       queueMsgs(queueMsgs_def), queueUpdateMsgs(queueUpdateMsgs_def)
{
    if(site) {
        url=site->getURL();
        url.setPath("/" + name);
        site->acquire(); // released by: excise() or destructor
    }
}

VobjectImplementation::~VobjectImplementation()
{
    LOG("Vobject", 3, "deleting " << url.getString());

    if(site) {
        LOG("refcount", 5, "count on site " << site->getURL().getString() << " is " << site->getCount());
        site->release(); // acquired by: constructor
    }

    for(set<ParentChangeListener*>::iterator i = parentListeners.begin(); i != parentListeners.end(); i++) {
        if(RefCounted* rc = dynamic_cast<RefCounted*>(*i)) {
            rc->removeExciseListener(this, false);
            rc->release();
        }
    }
    for(set<ChildChangeListener*>::iterator i = childListeners.begin(); i != childListeners.end(); i++) {
        if(RefCounted* rc = dynamic_cast<RefCounted*>(*i)) {
            rc->removeExciseListener(this, false);
            rc->release();
        }
    }
    for(set<TypeChangeListener*>::iterator i = typeListeners.begin(); i != typeListeners.end(); i++) {
        if(RefCounted* rc = dynamic_cast<RefCounted*>(*i)) {
            rc->removeExciseListener(this, false);
            rc->release();
        }
    }
}

Site& VobjectImplementation::getSite() {
    site->acquire(); // released by: the caller of this method
    return *site;
}

const set<string>& VobjectImplementation::getTypes() throw (AccessControlError, RemoteError)
{ return types; }

const set<Vobject::ParentChildRelation*,
          Vobject::ParentChildRelation::Cmp>& VobjectImplementation::getParents()
    throw (AccessControlError, RemoteError)
{ return parents; }

const deque<Vobject::ParentChildRelation*>& VobjectImplementation::getChildren()
    throw (AccessControlError, RemoteError)
{ return children; }

Vobject& Vobject::findObjectFromRoot(const string& path)
    throw (NoSuchSiteError, NoSuchObjectError, URL::BadURLError, AccessControlError, RemoteError)
{
    if(path.substr(0, 6) != "vop://") throw NoSuchObjectError("Object path doesn't start with vop://");
    URL u(path);
    string s;
    s += u.getHostAndPort();
    Site& objsite=Site::findSite(s);

    if(u.getPath() == "") {
        // pass reference through
        return objsite;
    } else {
        // pass reference to 'v' through
        try {
            Vobject& v = objsite.findObject(u.getPath());
            objsite.release(); // acquired by: findSite() above
            return v;
        } catch(...) {
            objsite.release(); // acquired by: findSite() above
            throw;
        }
    }
}

Vobject::ParentChildRelation& VobjectImplementation::findChild(const string& path)
    throw (NoSuchObjectError, AccessControlError, RemoteError)
{
    if(path[0] == '#') {
        int pos=atoi(path.substr(1).c_str());
        if(pos < 0) pos=children.size()+pos;
        if((unsigned int)pos >= children.size()) throw NoSuchObjectError(string("Object position out of range: ") +  path);
        Vobject::ParentChildRelation* child=children[pos];
        if(child == 0) throw NoSuchObjectError("Object at position not aquired (BUG!)");
        child->acquire(); // released by: the caller of this method
        return *child;
    } else {
        map<string, Vobject::ParentChildRelation*>::iterator it=children_map.find(path);
        if(it == children_map.end()) throw NoSuchObjectError(string("No object by that name: ") + path);
        ((*it).second)->acquire(); // released by: the caller of this method
        return *((*it).second);
    }
}

Vobject::ParentChildRelation& VobjectImplementation::findParent(Vobject& parent)
    throw (NoSuchObjectError, AccessControlError, RemoteError)
{
    for(set<Vobject::ParentChildRelation*, Vobject::ParentChildRelation::Cmp>::const_iterator piter = getParents().begin();
          piter != parents.end();
          piter++) {
        //LOG("Vobject", 5, "comparing " << (*piter)->parent->getSite().getURL().getString() << " to " << parent.getSite().getURL().getString());
        //LOG("Vobject", 5, "comparing " << (*piter)->parent->getName() << " to " << parent.getName());
        if(*((*piter)->parent) == parent) {
            (*piter)->acquire(); // released by: the caller of this method
            return **piter;
        }
    }
    throw NoSuchObjectError("Supplied object is not a parent");
}

Vobject& VobjectImplementation::findObject(const string& path)
    throw (NoSuchSiteError, NoSuchObjectError, URL::BadURLError, AccessControlError, RemoteError)
{
    if(path.substr(0, 6) == "vop://") {
        // pass reference through
        return findObjectFromRoot(path);
    }
    if(path == "") {
        acquire(); // released by: the caller of this method
        return *this;
    }
    if(path == "/" ) throw NoSuchObjectError("\"/\" is not a legal path");
    unsigned int nextpart;
    if(path[0] == '/') {
        // pass reference through
        rREF(Site&, site, getSite(),
             Vobject& v = site.findObject(path.substr(1));
             site.release(); // acquired by: getSite() above
             return v;
            ); // will catch any exceptions, release the site, and re-throw the exception
    }
    nextpart=path.find("/");
    string cur=path.substr(0, nextpart);
    string rest;
    if(nextpart != string::npos) rest=path.substr(nextpart+1);

    Vobject* child;
    rREF(Vobject::ParentChildRelation&, pcr, findChild(cur), child = pcr.child);
    if(! child) throw NoSuchObjectError("Object not available");
    if(rest == "") {
        child->acquire(); // released by: the caller of this method
        return *child;
    } else {
        // pass reference through
        return child->findObject(rest);
    }
}

void VobjectImplementation::insertChild(int pos, const string& context_name, Vobject* child)
    throw (AccessControlError, RemoteError)
{

    if(pos < 0) pos = children.size() + pos + 1;

    if(MetaObject* m = dynamic_cast<MetaObject*>(child)) {
        child=m->getTopObject();
    }

    vRef<Site> thissite = getSite();

    vRef<Vobject::ParentChildRelation> c = new Vobject::ParentChildRelation(child, this);
    c->position=pos;
    c->contextual_name=context_name;

    if(children.size() < (unsigned int)pos) {
        children.resize(pos, 0);
    }

    c->acquire(); // released by: removeChild() or setChild()
    // since both children and children_map[] are manipulated in
    // parallel, consider it a single reference
    children.insert(children.begin()+pos, &c);
    children_map[context_name]=&c;

    for(unsigned int i=pos+1; i < children.size(); i++) {
        if(children[i]) children[i]->position++;
    }

    if(VobjectImplementation* v = dynamic_cast<VobjectImplementation*>(child)) {
        /* because the child now has a reference to c as well */
        c->acquire(); // released by: removeChild() or setChild()
        v->parents.insert(&c);

        for(set<ParentChangeListener*>::iterator i = v->parentListeners.begin();
            i != v->parentListeners.end(); i++)
        {
            /*    try {
                (*i)->notifyParentInserted(*v, *this, pos, context_name);
            } catch(runtime_error x) {
                LOG("refcount", 0, "call to notifyParentInserted emitted exception: " << x.what());
                } catch(...) { }*/

            thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ParentInserted,
                                                             v, this, pos, context_name));
        }
        LOG("insertChild", 3, "did add " << c->parent->getURL().getString() << " as a parent for "
            << c->child->getURL().getString() << "(count " << c->child->getCount() << ") at position " << pos << ", size of parents is " << v->parents.size());
    }

    for(set<ChildChangeListener*>::iterator i = childListeners.begin();
        i != childListeners.end(); i++)
    {
        /*try {
            (*i)->notifyChildInserted(*this, pos, context_name, *child);
        } catch(runtime_error x) {
            LOG("refcount", 0, "call to notifyChildInserted emitted exception: " << x.what());
            } catch(...) { }*/
        thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ChildInserted,
                                                         this, pos, context_name, child));
    }
}


/// @bug is there an unspec'ed exception in this method?
void VobjectImplementation::setChild(int position, const string& contextual_name, Vobject* child)
    throw (AccessControlError, RemoteError)
{
    if(! child) return;
    if(position < 0) position=children.size()+position;

    if(MetaObject* m = dynamic_cast<MetaObject*>(child)) {
        child=m->getTopObject();
    }

    LOG("vobject", 5, "position " << position << "  size " << children.size());
    if(children.size() > (unsigned int)position) {
        LOG("vobject", 5, "oldedge is " << children[position]);
    }
    else {
        LOG("vobject", 5, "position doesn't fit");
    }

    if(children.size() <= (unsigned int)position) {
        children.resize(position+1, 0);
    }

    Vobject* oldchild = 0;

    vRef<Site> thissite = getSite();

    ParentChildRelation* oldedge = children[position];
    LOG("vobject", 4, "entered setChild on " << getURL().getString() << " for child " << child->getURL().getString()
        << "(" << contextual_name << ")" << " and oldedge is " << oldedge);
    if(oldedge) {
        if(oldedge->child == child && oldedge->contextual_name == contextual_name) {
            LOG("vobject", 5, "new child/pos/contextname same as old one.  sending notifications but otherwise ignoring");
            /*if(position == 3 && children.size() == 5 && contextual_name == "orientation"
                && child->getName() == "719885386") {
                raise(SIGINT);
                }*/
             for(set<ChildChangeListener*>::iterator i = childListeners.begin();
                 i != childListeners.end(); i++)
             {
                 //try {
                     //(*i)->notifyChildReplaced(*this, position, contextual_name, *child, *oldedge->child);
                 //} catch(runtime_error x) {
                 //  LOG("refcount", 0, "call to notifyChildReplaced emitted exception: " << x.what());
                 //} catch(...) { }

                 thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ChildReplaced,
                                                              this, position, contextual_name,
                                                              child, oldedge->child));
             }
             thissite->flushNotifications();
             return;
        }

        oldedge->child->acquire(); // released below (after doing notifications)
        oldchild = oldedge->child;

        if(VobjectImplementation* v = dynamic_cast<VobjectImplementation*>(oldedge->child)) {
            v->parents.erase(children[position]);
            for(set<ParentChangeListener*>::iterator i = v->parentListeners.begin();
                i != v->parentListeners.end(); i++) {
                //try {
                    //(*i)->notifyParentRemoved(*v, *this, oldedge->position, oldedge->contextual_name);
                thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ParentRemoved,
                                                              v, this, oldedge->position,
                                                              oldedge->contextual_name));

                                       //} catch(runtime_error x) {
                                       //LOG("vobject", 0, "call to notifyParentRemoved emitted exception: " << x.what());
                                       //} catch(...) { }
                                       //}
            }
        }

        LOG("vobject", 5, "about to release oldedge twice, count is " << oldedge->getCount());

        /* release twice, once for parent, once for child */
        oldedge->release(); // acquired by: insertChild() or setChild()
        oldedge->release(); // acquired by: insertChild() or setChild()
    }

    LOG("vobject", 5, "about to create a pcr, count on child is " << getCount());
    vRef<Vobject::ParentChildRelation> c = new Vobject::ParentChildRelation(child, this);

    c->position=position;
    c->contextual_name=contextual_name;

    c->acquire(); // released by: removeChild() or setChild()
    // since both children and children_map[] are manipulated in
    // parallel, consider it a single reference
    children[position]=&c;
    children_map[contextual_name]=&c;

    if(VobjectImplementation* v = dynamic_cast<VobjectImplementation*>(child)) {
        /* because the child now has a reference to c as well */
        c->acquire(); // released by: setChild() or removeChild()
        v->parents.insert(&c);

        for(set<ParentChangeListener*>::iterator i = v->parentListeners.begin();
            i != v->parentListeners.end(); i++)
        {

            thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ParentInserted,
                                                         v, this, position,
                                                         contextual_name));
            //try {
            //(*i)->notifyParentInserted(*v, *this, position, contextual_name);
            //} catch(runtime_error x) {
            //LOG("vobject", 0, "call to notifyParentInserted emitted exception: " << x.what());
            //} catch(...) { }
        }

        LOG("setChild", 4, "did add " << c->parent->getURL().getString() << " as a parent for "
            << child->getURL().getString() << " at position " << position << ", size of parents is " << v->parents.size() << ", and size of children " << children.size());

        /*
          for(int foo = 0; foo < children.size(); foo++) {
          ParentChildRelation* ch = children[foo];
          LOG("Vobject", 4, "---");
          for(set<ParentChildRelation*, Vobject::ParentChildRelation::Cmp>::iterator i = ch->child->getParents().begin();
          i != ch->child->getParents().end(); i++) {
          LOG("Vobject", 4, (*i)->parent->getURL().getString() << " is parent of "
          << (*i)->child->getURL().getString());
          }
          }
        */
    }

    if(oldchild) {
        for(set<ChildChangeListener*>::iterator i = childListeners.begin();
            i != childListeners.end(); i++) {
            /*try {
              (*i)->notifyChildReplaced(*this, position, contextual_name, *child, *oldchild);
              } catch(runtime_error x) {
              LOG("refcount", 0, "call to notifyChildReplaced emitted exception: " << x.what());
              } catch(...) { }*/
            thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ChildReplaced,
                                                             this, position, contextual_name,
                                                             child, oldchild));
        }
        oldchild->release(); // acquired above (when releasing old edge)
    } else {
        for(set<ChildChangeListener*>::iterator i = childListeners.begin();
            i != childListeners.end(); i++)
        {
            /*try {
              (*i)->notifyChildInserted(*this, position, contextual_name, *child);
              } catch(runtime_error x) {
              LOG("refcount", 0, "call to notifyChildInserted emitted exception: " << x.what());
              } catch(...) { }*/
            thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ChildInserted,
                                                             this, position, contextual_name,
                                                             child));

        }
    }

    thissite->flushNotifications();

    LOG("setChild", 4, getURL().getString() << " children.size() == " << children.size());
}


void VobjectImplementation::removeChild(int pos)
    throw (AccessControlError, RemoteError)
{
    if(pos < 0) pos=children.size()+pos;
    if((unsigned int)pos >= children.size()) pos = pos % children.size();
    vRef<Vobject::ParentChildRelation> c = children[pos];
    //LOG("Vobject", 2, "size before erase is " << children.size());
    children.erase(children.begin() + pos);
    //LOG("Vobject", 2, "size after erase is " << children.size());
    if(&c) {
        children_map.erase(c->contextual_name);

        for(unsigned int i=pos; i < children.size(); i++) {
            if(children[i]) children[i]->position--;
        }

        string context_name = c->contextual_name;
        Vobject* child = c->child;

        if(MetaObject* m = dynamic_cast<MetaObject*>(child)) {
            child=m->getTopObject();
        }

        vRef<Site> thissite = getSite();

        if(VobjectImplementation* v = dynamic_cast<VobjectImplementation*>(child)) {
            v->parents.erase(&c);
            c->release(); // acquired by: insertChild() or setChild()

            for(set<ParentChangeListener*>::iterator i = v->parentListeners.begin();
                i != v->parentListeners.end(); i++)
            {
                /*try {
                  (*i)->notifyParentRemoved(*v, *this, c->position, c->contextual_name);
                  } catch(runtime_error x) {
                  LOG("refcount", 0, "call to notifyParentRemoved emitted exception: " << x.what());
                  } catch(...) { }*/
                thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ParentRemoved,
                                                                 v, this, c->position, c->contextual_name));
            }
        }

        if(child) {
            for(set<ChildChangeListener*>::iterator i = childListeners.begin();
                i != childListeners.end(); i++)
            {
                thissite->addNotification(new VobjectNotifyEvent(*i, VobjectNotifyEvent::ChildRemoved,
                                                                 this, pos, context_name, child));
            }
        }
        thissite->flushNotifications();
    }
}

bool VobjectImplementation::hasMessageAvailable()
{
    rREF(Site&, site, getSite(), site.flushIncomingBuffers());
    return (!incomingMessageQueue.empty());
}

/* get the next message this object has received */
Message* VobjectImplementation::receiveMessage() throw (MessageQueueEmptyError)
{
    rREF(Site&, site, getSite(), site.flushIncomingBuffers());

    Message* m;
    if(incomingMessageQueue.empty()) throw MessageQueueEmptyError("No messages available");
    m = incomingMessageQueue.front();
    incomingMessageQueue.pop_front();
    // pass the reference through
    return m;
}

void VobjectImplementation::sendUpdateMessage(Message* m)
{
    if(queueUpdateMsgs) {
        m->acquire(); // released by: the caller of receiveUpdateMessage()
        incomingUpdateMessageQueue.push_back(m);
        // do not release "m" because we are holding onto
        // a reference to it
    }
}

Message* VobjectImplementation::receiveUpdateMessage() throw (MessageQueueEmptyError)
{
    rREF(Site&, site, getSite(), site.flushIncomingBuffers());

    Message* m;
    if(incomingUpdateMessageQueue.empty()) throw MessageQueueEmptyError("No messages available");
    m = incomingUpdateMessageQueue.front();
    incomingUpdateMessageQueue.pop_front();
    return m;
    // do not release because we are implicitly transfering
    // the acquire from incomingMessageQueue to the calling method
}

bool VobjectImplementation::hasUpdateMessageAvailable()
{
    rREF(Site&, site, getSite(), site.flushIncomingBuffers());
    return (!incomingUpdateMessageQueue.empty());
}

void VobjectImplementation::addTypeListener(TypeChangeListener* tl, bool refresh)
{
    if(RefCounted* rc = dynamic_cast<RefCounted*>(tl)) {
        rc->acquire(); // released by: removeTypeListener() or this destructor
        rc->addExciseListener(this);
    }
    typeListeners.insert(tl);

    if(refresh) {
        TypeSet tmptypeset = types;
        for(set<string>::iterator it = tmptypeset.begin();
            it != tmptypeset.end(); it++) {
            try {
                tl->notifyTypeInserted(*this, (*it));
            } catch(runtime_error x) {
                LOG("vobject", 0, "call to notifyTypeInserted emitted exception: " << x.what());
            } catch(...) { }
        }
    }
}

void VobjectImplementation::addParentListener(ParentChangeListener* pl, bool refresh)
{
    if(RefCounted* rc = dynamic_cast<RefCounted*>(pl)) {
        rc->acquire(); // released by: removeParentListener() or this destructor
        rc->addExciseListener(this);
    }
    parentListeners.insert(pl);

    if(refresh) {
        ParentSet tmpparentset = parents;
        for(set<ParentChildRelation*, ParentChildRelation::Cmp>::iterator it = tmpparentset.begin();
            it != tmpparentset.end(); it++) {
            try {
                if((*it)->parent) pl->notifyParentInserted(*this, *((*it)->parent), (*it)->position, (*it)->contextual_name);
            } catch(runtime_error x) {
                LOG("vobject", 0, "call to notifyParentInserted emitted exception: " << x.what());
            } catch(...) { }
        }
    }
}

void VobjectImplementation::addChildListener(ChildChangeListener* cl, bool refresh)
{
    if(RefCounted* rc = dynamic_cast<RefCounted*>(cl)) {
        rc->acquire(); // released by: removeChildListener() or this destructor
        rc->addExciseListener(this);
    }
    childListeners.insert(cl);

    if(refresh) {
        ChildList cc = children;
        for(unsigned int it = 0; it < cc.size(); it++) {
            if(cc[it]) cc[it]->acquire();
        }
        for(unsigned int it = 0; it < cc.size(); it++) {
            if(cc[it]) {
                if(cc[it]->getCount() > 1) {
                    try {
                        ParentChildRelation* pcr = cc[it];
                        if(pcr->child) {
                            cl->notifyChildInserted(*this, pcr->position,
                                                    pcr->contextual_name,
                                                    *(pcr->child));
                        }
                    } catch(runtime_error x) {
                        LOG("vobject", 0, "call to notifyChildInserted emitted exception: " << x.what());
                    } catch(...) {
                        LOG("vobject", 0, "call to notifyChildInserted emitted unknown exception!");
                    }
                }
                cc[it]->release();
            }
        }
    }
}

void VobjectImplementation::removeTypeListener(TypeChangeListener* tl)
{
    if(typeListeners.count(tl)) {
        typeListeners.erase(tl);
        if(RefCounted* rc = dynamic_cast<RefCounted*>(tl)) {
            rc->removeExciseListener(this);
            rc->release(); // acquired by: addTypeListener()
        }
    }
}

void VobjectImplementation::removeParentListener(ParentChangeListener* pl)
{
    if(parentListeners.count(pl)) {
        parentListeners.erase(pl);
        if(RefCounted* rc = dynamic_cast<RefCounted*>(pl)) {
            rc->removeExciseListener(this);
            rc->release(); // acquired by: addParentListener()
        }
    }
}

void VobjectImplementation::removeChildListener(ChildChangeListener* cl)
{
    if(childListeners.count(cl)) {
        childListeners.erase(cl);
        if(RefCounted* rc = dynamic_cast<RefCounted*>(cl)) {
            rc->removeExciseListener(this);
            rc->release(); // acquired by: addChildListener()
        }
    }
}

void VobjectImplementation::notifyObjectExcise(RefCounted* rc)
{
    if(TypeChangeListener* tl = dynamic_cast<TypeChangeListener*>(rc)) removeTypeListener(tl);
    if(ParentChangeListener* pl = dynamic_cast<ParentChangeListener*>(rc)) removeParentListener(pl);
    if(ChildChangeListener* cl = dynamic_cast<ChildChangeListener*>(rc)) removeChildListener(cl);

    for(HandlerMap::iterator it = msghandlers.begin(); it != msghandlers.end(); ) {
        if((*it).second->holds(rc)) {
            HandlerMap::iterator tmp = it;
            delete (*it).second;
            it++;
            msghandlers.erase(tmp);
        } else it++;
    }
    for(HandlerMap::iterator it = updatehandlers.begin(); it != updatehandlers.end(); ) {
        if((*it).second->holds(rc)) {
            HandlerMap::iterator tmp = it;
            delete (*it).second;
            it++;
            updatehandlers.erase(tmp);
        } else it++;
    }
}

void VobjectImplementation::addType(const string& s)
{
    if(s != "" && !types.count(s)) {
        for(TypeSet::iterator i = types.begin(); i != types.end(); i++) {
            if((*i).substr(0, s.size()) == s
               && (*i).substr(s.size(), 1) == ".")
            {
                return;
            }
        }
        types.insert(s);

        for(set<TypeChangeListener*>::iterator i = typeListeners.begin();
            i != typeListeners.end();
            i++) {
            try {
                (*i)->notifyTypeInserted(*this, s);
            } catch(runtime_error x) {
                LOG("refcount", 0, "call to notifyTypeInserted emitted exception: " << x.what());
            } catch(...) { }
        }
    }
}

void VobjectImplementation::excise()
{
    if(exciseCalled) return;
    else exciseCalled = true;

    RefCounted::excise();

    //if(site) site->release(); // acquired by: constructor
    //site=0;

    for(int i=children.size() - 1; i >= 0; i--) {
        VobjectImplementation::removeChild(i);
    }

    // copy it so as to avoid concurrently modifying the _same_ set object, which would be baaaaad.
    set<ParentChildRelation*, Vobject::ParentChildRelation::Cmp> parentbuf = parents;
    LOG("Vobject", 4, "parents size is " << parentbuf.size());
    for(set<ParentChildRelation*, Vobject::ParentChildRelation::Cmp>::iterator it = parentbuf.begin();
        it != parentbuf.end();
        it++) {
        LOG("Vobject", 4, "parents size is " << parents.size());
        try {
            if(VobjectImplementation* p = dynamic_cast<VobjectImplementation*>((*it)->parent)) {
                LOG("Vobject", 4, "removing parent " << p->getURL().getString() << " of child " << getURL().getString());
                if(p->isRemote()) p->setChild((*it)->position, (*it)->contextual_name, 0);
                else p->VobjectImplementation::removeChild((*it)->position);
            }
        } catch(AccessControlError) { }
    }

    for(set<ParentChangeListener*>::iterator i = parentListeners.begin(); i != parentListeners.end(); i++) {
        if(RefCounted* rc = dynamic_cast<RefCounted*>(*i)) {
            rc->removeExciseListener(this);
            rc->release();
        }
    }
    for(set<ChildChangeListener*>::iterator i = childListeners.begin(); i != childListeners.end(); i++) {
        if(RefCounted* rc = dynamic_cast<RefCounted*>(*i)) {
            rc->removeExciseListener(this);
            rc->release();
        }
    }
    for(set<TypeChangeListener*>::iterator i = typeListeners.begin(); i != typeListeners.end(); i++) {
        if(RefCounted* rc = dynamic_cast<RefCounted*>(*i)) {
            rc->removeExciseListener(this);
            rc->release();
        }
    }
    parentListeners.clear();
    childListeners.clear();
    typeListeners.clear();

    for(HandlerMap::iterator it = msghandlers.begin(); it != msghandlers.end(); it++) {
        delete (*it).second;
    }
    for(HandlerMap::iterator it = updatehandlers.begin(); it != updatehandlers.end(); it++) {
        delete (*it).second;
    }
    msghandlers.clear();
    updatehandlers.clear();

    LOG("Vobject", 4, "excise: refcount on this is " << getCount());
    if(getCount() < 1) {
        LOG("Vobject", 0, "excise: refcount on this is " << getCount() << "!  The method which called excise() should be holding the last reference.  (I'm going to abort now).");
        abort();
    }
}

void VobjectImplementation::saveState(MessageBlock& output, set<string>& t, bool portable)
{
    t = types;
}

void VobjectImplementation::addFlag(const string& flag)
{
    flagstrings.insert(flag);
}

void VobjectImplementation::removeFlag(const string& flag)
{
    flagstrings.erase(flag);
}

bool VobjectImplementation::checkFlag(const string& flag)
{
    return (flagstrings.count(flag) > 0);
}

---