vos/corelibs/vos/remotevobject.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 "remotesite.hh"
#include "message.hh"

using namespace VOS;

#include <stdio.h>
#include <signal.h> // this is temporary and not very portable

#include <string>
#include <algorithm>

/** @file
    Implements RemoteVobject.
*/

RemoteVobject::RemoteVobject(const string& name, RemoteSite* s)
    : VobjectImplementation(name, s, false), resetChildren(false)
{
    addUpdateHandler<RemoteVobject>("core:set-child-update", this, &RemoteVobject::addChildUpdateHandler);
    addUpdateHandler<RemoteVobject>("core:insert-child-update", this, &RemoteVobject::addChildUpdateHandler);
    addUpdateHandler<RemoteVobject>("core:insert-parent-update", this, &RemoteVobject::addParentUpdateHandler);
    addUpdateHandler<RemoteVobject>("core:remove-child-update", this, &RemoteVobject::removeChildUpdateHandler);
    addUpdateHandler<RemoteVobject>("core:remove-parent-update", this, &RemoteVobject::removeParentUpdateHandler);
    addUpdateHandler<RemoteVobject>("core:type-add-update", this, &RemoteVobject::typeUpdateHandler);
    addUpdateHandler<RemoteVobject>("core:start-listening-reply", this, &RemoteVobject::addListenerReplyHandler);
}

void RemoteVobject::sendMessage(Message* m)
{
    rREF(Site&, site, getSite(), site.sendMessage(m));
}

void RemoteVobject::sendMessage(MessageBlock* mb)
{
    rREF(Site&, site, getSite(), site.sendMessage(mb));
}

RemoteVobject::~RemoteVobject()
{
}

LocalSite& RemoteVobject::initFields(Vobject* v, Message* m, const string& method, bool withnonce)
{
    m->setType("message");
    LocalSite* ls;
    vRef<Site> s = v->getSite();
    ls = &(dynamic_cast<RemoteSite*>(&s)->getLocalPeer()); // released by: the caller of this method

    m->setFrom(ls->getURL().getString());
    m->setTo(v->getURL().getString());
    m->setMethod(method);
    if(withnonce) m->generateNonce();

    // pass reference to ls through
    return *ls;
}

Vobject& RemoteVobject::findObject(const string& path)
    throw (NoSuchSiteError, NoSuchObjectError, URL::BadURLError, AccessControlError, RemoteError)
{
    try {
        // pass reference through
        return VobjectImplementation::findObject(path);
    } catch(NoSuchObjectError) { }

    unsigned int nextpart;
    string nextchild;
    if(path[0] == '/') {
        rREF(Site&, site, getSite(),
             Vobject& v = site.findObject(path.substr(1));
             site.release();   // acquired by: getSite() above
             return v;         // pass reference through
            ); // will catch any exceptions, release the site, and re-throw the exception
    } else {
        nextpart = (unsigned int)path.find("/");
        nextchild = path.substr(0, nextpart).c_str();
    }

    vRef<ParentChildRelation> f = findChild(nextchild);
    /*
    pREF(Message*, m, new Message(),
         rREF(LocalSite&, ls, initFields(this, m, "core:find-child", true),
              m->insertField(-1, "path", nextchild);

              sendMessage(m);
              rREF(Site&, site, getSite(),
                   pREF(Message*, r, ls.waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site)), ));
             );
        );
    */
    // pass reference through
    return VobjectImplementation::findObject(path);
}

const deque<Vobject::ParentChildRelation*>& RemoteVobject::getChildren() throw (AccessControlError, RemoteError)
{
    if(childListeners.empty()) {
        vRef<Message> m = new Message();
        vRef<LocalSite> ls = initFields(this, &m, "core:find-child", true);
        m->insertField(-1, "path", "#0");
        m->insertField(-1, "to", "");
        m->insertField(-1, "path", "#-1");

        sendMessage(&m);

        resetChildren = true;

        vRef<Site> site = getSite();
        vRef<Message> r = ls->waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site));
    }

    return children;
}

const set<Vobject::ParentChildRelation*, Vobject::ParentChildRelation::Cmp>& RemoteVobject::getParents()
    throw (AccessControlError, RemoteError)
{
    if(parentListeners.empty()) {
        pREF(Message*, m, new Message(),
             rREF(Site&, site, getSite(),
                  rREF(LocalSite&, ls, initFields(this, m, "core:get-parents", true),
                       sendMessage(m);
                       pREF(Message*, r, ls.waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site)), );
                      );
                 );
            );
    }

    return parents;
}

void RemoteVobject::addChildUpdateHandler(Message* m)
{
    vRef<Site> s = getSite();
    try {
        if(&s == dynamic_cast<Site*>(this)) {
            resetChildren=false;
        } else {
            if(resetChildren && m->getMethod() == "core:set-child-update") {
                if(children.size() > 0) {
                    for(int i = (int)children.size() - 1; i >= 0; i--) {
                        VobjectImplementation::removeChild(this, i);
                    }
                }
                resetChildren=false;
            }
            s->lockNotificationFlush();
            for(int i=0; i < m->getNumFields(); ++i) {
                const Message::Field& pos=m->getField(i);
                if(pos.key != "pos") break;
                const Message::Field& name=m->getField(++i);
                if(name.key != "name") break;
                const Message::Field& path=m->getField(++i);
                if(path.key != "path") break;
                try {
                    int position=abs(atoi(pos.value.c_str()));
                    LOG("sendUpdateMessage", 5, "adding child " + name.value
                        + " at position " + pos.value);
                    vRef<Vobject> child = Vobject::findObjectFromRoot(path.value);
                    /*if(! (position < children.size()
                      && children[position]
                      && children[position]->child == child
                      && children[position]->contextual_name == name.value)) {*/
                    bool clc=false;
                    //bool lc=false;
                    bool clp=false;
                    bool plp=false;
                    bool plc=false;
                    vRef<RemoteSite> cs = dynamic_cast<RemoteSite*>(&(child->getSite()));
                    if(childListeners.count(&cs)) {
                        clc=true;
                        childListeners.erase(&cs);
                    }
                    if(parentListeners.count(&cs)) {
                        plc=true;
                        parentListeners.erase(&cs);

                    }
                    vRef<RemoteSite> ps = dynamic_cast<RemoteSite*>(&(getSite()));
                    if(childListeners.count(&*(ps))) {
                        clp=true;
                        childListeners.erase(&ps);
                    }
                    if(parentListeners.count(&ps)) {
                        plp=true;
                        parentListeners.erase(&ps);
                    }

                    if(m->getMethod() == "core:set-child-update")
                        VobjectImplementation::setChild(this, position, name.value, &child);
                    else
                        VobjectImplementation::insertChild(this, position, name.value, &child);

                    if(clc) childListeners.insert(&cs);
                    if(plc) parentListeners.insert(&cs);
                    if(clp) childListeners.insert(&ps);
                    if(plp) parentListeners.insert(&ps);
                } catch(NoSuchSiteError) {
                } catch(NoSuchObjectError) {
                } catch(URL::BadURLError) {
                } catch(AccessControlError) {
                } catch(RemoteError) {
                }
            }
        }
        s->unlockNotificationFlush();
    } catch(Message::NoSuchFieldError) {
        s->unlockNotificationFlush();
        LOG("remotevobject", 2, "Message missing a field on insert/set child?");
    } catch(runtime_error e) {
        s->unlockNotificationFlush();
        LOG("remotevobject", 2, "Caught exception processing insert/set child: " << e.what());
    } catch(...) {
        LOG("remotevobject", 2, "Something very bad just happened in insert/set child!");
        s->unlockNotificationFlush();
    }
}

void RemoteVobject::addParentUpdateHandler(Message* m)
{
    try {
        for(int i=0; i < m->getNumFields(); ++i) {
            const Message::Field& pos=m->getField(i);
            if(pos.key != "pos") break;
            const Message::Field& name=m->getField(++i);
            if(name.key != "name") break;
            const Message::Field& path=m->getField(++i);
            if(path.key != "path") break;
            try {
                int position=atoi(pos.value.c_str());
                LOG("sendUpdateMessage", 5, "adding parent " + name.value
                    + " at position " + pos.value);
                pREF(Vobject*, parent, &(Vobject::findObjectFromRoot(path.value)),
                     if(MetaObject *m=dynamic_cast<MetaObject*>(parent)) parent=m->getTopObject();
                     RemoteVobject* rvo = dynamic_cast<RemoteVobject*>(parent);
                     if(rvo && rvo->childListeners.empty()) {
                         rvo->VobjectImplementation::setChild(this, position, name.value, this);
                     }
                    );
            } catch(NoSuchObjectError) { }
        }
    } catch(Message::NoSuchFieldError) { }
}

void RemoteVobject::removeChildUpdateHandler(Message* m)
{
    try {
        for(int i=0; i < m->getNumFields(); ++i) {
            const Message::Field& pos=m->getField(i);
            if(pos.key != "pos") break;
            const Message::Field& name=m->getField(++i);
            if(name.key != "name") break;
            const Message::Field& path=m->getField(++i);
            if(path.key != "path") break;

            try {
                //rREF(Vobject&, v, Vobject::findObjectFromRoot(path.value),
                unsigned int posi=abs(atoi(pos.value.c_str()));
                if(posi < children.size() && children[posi] && children[posi]->contextual_name == name.value
                   /*&& *children[posi]->child == v*/) {
                    VobjectImplementation::removeChild(this, posi);
                }
                //);
            } catch(NoSuchObjectError) {
            }
        }
    } catch(Message::NoSuchFieldError) {
    }
}

void RemoteVobject::removeParentUpdateHandler(Message* m)
{
    try {
        for(int i=0; i < m->getNumFields(); ++i) {
            const Message::Field& pos=m->getField(i);
            if(pos.key != "pos") break;
            const Message::Field& name=m->getField(++i);
            if(name.key != "name") break;
            const Message::Field& path=m->getField(++i);
            if(path.key != "path") break;
            try {
                int position=atoi(pos.value.c_str());
                LOG("sendUpdateMessage", 5, "removing parent " + name.value
                    + " at position " + pos.value);
                pREF(Vobject*, parent, &(Vobject::findObjectFromRoot(path.value)),
                     RemoteVobject* rvo = dynamic_cast<RemoteVobject*>(parent);
                     if(rvo && rvo->childListeners.empty()) {
                         parent->removeChild(position);
                     }
                    );
            } catch(NoSuchObjectError) { }
        }
    } catch(Message::NoSuchFieldError) { }
}

void RemoteVobject::typeUpdateHandler(Message* m)
{
    for(int i=0; i < m->getNumFields(); ++i) {
        const Message::Field& t=m->getField(i);
        if(t.key == "type") types.insert(t.value);
    }
}



void RemoteVobject::sendUpdateMessage(Message* m)
{
    //LOG("refcount", 5, "sendUpdateMessage: count on this rv's rs is " << site->getCount());
    LOG("refcount", 5, "before sending to VobjectImp::sendUpdateMessage count on message " << m->getCount());
    VobjectImplementation::sendUpdateMessage(m);
    LOG("refcount", 5, "after sending to VobjectImp::sendUpdateMessage count on message " << m->getCount());


    LOG("refcount", 5, "before doing stuff, count on message " << m->getCount() << " numchildren " << (unsigned int)children.size());

    pair<HandlerMap::iterator, HandlerMap::iterator> hndls = updatehandlers.equal_range(m->getMethod());
    for(HandlerMap::iterator i = hndls.first; i !=  hndls.second; i++) {
        try {
            (*i).second->sendMessage(m);
        } catch(NoSuchObjectError) {
        } catch(NoSuchSiteError) {
        } catch(URL::BadURLError) {
        } catch(AccessControlError) {
        }
    }

    LOG("refcount", 5, "after doing stuff, count on message " << m->getCount());


    //LOG("refcount", 5, "sendUpdateMessage: count on this rv's rs NOW is " << site->getCount());
}

void RemoteVobject::addListenerReplyHandler(Message* m)
{
    try {
        const Message::Field& f = m->getField("listen");
        if(f.value == "types") {
            VobjectImplementation::addTypeListener(&DoNothingListener::static_);
        } else if(f.value == "parents") {
            VobjectImplementation::addParentListener(&DoNothingListener::static_);
        } else if(f.value == "children") {
            VobjectImplementation::addChildListener(&DoNothingListener::static_);
        }
    } catch(Message::NoSuchFieldError) { }
}

const set<string>& RemoteVobject::getTypes() throw (AccessControlError, RemoteError)
{
    try {
        //LOG("refcount", 5, "getTypes: count on this rv's rs is " << site->getCount());
        if(types.size() == 0) {
            pREF(Message*, m, new Message(),
                rREF(LocalSite&, ls, initFields(this, m, "core:get-types", true),
                    //LOG("refcount", 5, "getTypes: count on this rv's rs NOW is " << site->getCount());
                    sendMessage(m);
                    //LOG("refcount", 5, "getTypes: count on this rv's rs post-sendMsg is " << site->getCount());
                    rREF(Site&, site, getSite(),
                        pREF(Message*, r, ls.waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site)), ));
                    //LOG("refcount", 5, "getTypes: count on this rv's rs post-waitFor is " << site->getCount());
                    );
                );
        }
        return VobjectImplementation::getTypes();
    } catch(AccessControlError) {
        throw;
    } catch(RemoteError) {
        throw;
    } catch(exception& e) {
        LOG("RemoteVobject", 0, "ERROR (unexpected exception): " << e.what());
        throw;
    }
}

Vobject::ParentChildRelation& RemoteVobject::findChild(const string& path)
    throw (NoSuchObjectError, AccessControlError, RemoteError)
{
    try {
        // pass reference through
        return VobjectImplementation::findChild(path);
    } catch(NoSuchObjectError) {
        if(! childListeners.empty()) throw;
    }

    pREF(Message*, m, new Message(),
         rREF(LocalSite&, ls, initFields(this, m, "core:find-child", true),
              m->insertField(-1, "path", path);

              sendMessage(m);
              rREF(Site&, site, getSite(),
                   pREF(Message*, r, ls.waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site)), ));
             );
        );

    // pass reference through
    return VobjectImplementation::findChild(path);
}

/** @note supplying a NULL for child means release child object but do not delete parent-child relation... */
void RemoteVobject::setChild(int position, const string& contextual_name, Vobject* child)
    throw (AccessControlError, RemoteError)
{
    if(!child) {
        if(position < 0) position = (int)children.size() + position;
        if(position >= (int)children.size()) position = position % (int)children.size();
        ParentChildRelation* pcr = children[position];
        if(pcr->contextual_name != contextual_name) return;

        vRef<Site> thissite = getSite();

        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ChildRemove, *this, *this,
                                                    position, pcr->contextual_name, *(pcr->child));

        for(set<ChildChangeListener*>::iterator i = childListeners.begin();
            i != childListeners.end(); i++)
        {
            try {
                (*i)->notifyChildRemoved(*event);
            } catch(runtime_error e) {
                LOG("remotevobject", 2, "notifyChildRemoved emitted exception: " << e.what());
            } catch(...) {
                LOG("remotevobject", 2, "notifyChildRemoved emitted unknown exception");
            }
        }

        if(VobjectImplementation* v = dynamic_cast<VobjectImplementation*>(pcr->child)) {
            v->parents.erase(pcr);
            pcr->release(); // acquired by: insertChild() or setChild()
        }
        pcr->child->release(); // acquired by: insertChild() or setChild()
        pcr->child = 0;
        return;
    }

    if((int)children.size() > position
       && children[position]
       && children[position]->child == child
       && children[position]->contextual_name == contextual_name) return;

    pREF(Message*, m, new Message(),
         rREF(LocalSite&, ls, initFields(this, m, "core:set-child", true),
              char pos[16];
              snprintf(pos, sizeof(pos), "%i", position);
              m->insertField(-1, "pos", string(pos));
              m->insertField(-1, "name", contextual_name);
              m->insertField(-1, "path", child->getURL().getString());

              sendMessage(m);
              rREF(Site&, site, getSite(),
                   pREF(Message*, r, ls.waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site)), ));
             );
        );
}

void RemoteVobject::insertChild(int position, const string& contextual_name, Vobject* child)
    throw (AccessControlError, RemoteError)
{
    pREF(Message*, m, new Message(),
         rREF(LocalSite&, ls, initFields(this, m, "core:insert-child", true),
              char pos[16];
              snprintf(pos, sizeof(pos), "%i", position);
              m->insertField(-1, "pos", string(pos));
              m->insertField(-1, "name", contextual_name);
              m->insertField(-1, "path", child->getURL().getString());

              sendMessage(m);
              rREF(Site&, site, getSite(),
                   pREF(Message*, r, ls.waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site)), ));
             );
        );
}

void RemoteVobject::removeChild(int position)
    throw (AccessControlError, RemoteError)
{
    vRef<Message> m = new Message();
    vRef<LocalSite> ls = initFields(this, &m, "core:remove-child", true);
    char pos[16];
    snprintf(pos, sizeof(pos), "%i", position);
    m->insertField(-1, "pos", pos);
    m->insertField(-1, "name", children[position]->contextual_name);
    m->insertField(-1, "path", children[position]->child->getURL().getString());

    sendMessage(&m);

    vRef<Site> site = getSite();
    try{
        vRef<Message> r = ls->waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site));
    } catch(exception& e) {
        LOG("remotevobject", 2, "RemoteVobject::removeChild: caught exception from waitFor: " << e.what());
    }
}

void RemoteVobject::addTypeListener(TypeChangeListener* tl, bool refresh)
{
    if(typeListeners.empty() && refresh) {
            types.clear();

            vRef<Message> m = new Message();
            vRef<LocalSite> ls = initFields(this, &m, "core:start-listening", true);
            m->insertField(-1, "listen", "types");
            sendMessage(&m);
            vRef<Site> site = getSite();
            vRef<Message> r = ls->waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site));
    }
    VobjectImplementation::addTypeListener(tl, refresh);
}

void RemoteVobject::addParentListener(ParentChangeListener* pl, bool refresh)
{
    if(parentListeners.empty() && refresh) {
            vRef<Message> m = new Message();
            vRef<LocalSite> ls = initFields(this, &m, "core:start-listening", true);
            m->insertField(-1, "listen", "parents");

            sendMessage(&m);
            vRef<Site> site = getSite();
            vRef<Message> r = ls->waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site));
    }
    VobjectImplementation::addParentListener(pl, refresh);
}

void RemoteVobject::addChildListener(ChildChangeListener* cl, bool refresh)
{
    if(childListeners.empty() && refresh) {
        vRef<Message> m = new Message();
        vRef<LocalSite> ls = initFields(this, &m, "core:start-listening", true);
        m->insertField(-1, "listen", "children");

        sendMessage(&m);
        vRef<Site> site = getSite();
        vRef<Message> r = ls->waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site));
    }
    VobjectImplementation::addChildListener(cl, refresh);
}

void RemoteVobject::removeTypeListener(TypeChangeListener* tl)
{
    VobjectImplementation::removeTypeListener(tl);
    if(typeListeners.size() == 1 && typeListeners.count(&DoNothingListener::static_) == 1)
        typeListeners.erase(&DoNothingListener::static_);

    if(typeListeners.empty()) {
        pREF(Message*, m, new Message(),
             rREF(LocalSite&, ls, initFields(this, m, "core:stop-listening", false), );
             m->insertField(-1, "listen", "types");

             sendMessage(m);
            );
    }
}

void RemoteVobject::removeParentListener(ParentChangeListener* pl)
{
    VobjectImplementation::removeParentListener(pl);
    if(parentListeners.size() == 1 && parentListeners.count(&DoNothingListener::static_) == 1)
        parentListeners.erase(&DoNothingListener::static_);

    if(parentListeners.empty()) {
        pREF(Message*, m, new Message(),
             rREF(LocalSite&, ls, initFields(this, m, "core:stop-listening", false), );
             m->insertField(-1, "listen", "parents");

             sendMessage(m);
            );
    }
}

void RemoteVobject::removeChildListener(ChildChangeListener* cl)
{
    VobjectImplementation::removeChildListener(cl);
    if(childListeners.size() == 1 && childListeners.count(&DoNothingListener::static_) == 1)
        childListeners.erase(&DoNothingListener::static_);

    if(childListeners.empty()) {
        pREF(Message*, m, new Message(),
             rREF(LocalSite&, ls, initFields(this, m, "core:stop-listening", false), );
             m->insertField(-1, "listen", "children");

             sendMessage(m);
            );
    }
}

void RemoteVobject::addType(const string& s)
{
    vRef<Message> m = new Message();
    vRef<LocalSite> ls = initFields(this, &m, "core:type-add", true);
    m->insertField(-1, "type", s);

    sendMessage(&m);

    vRef<Site> site = getSite();
    try{
        vRef<Message> r = ls->waitFor(m->getNonce(), dynamic_cast<RemoteSite*>(&site));
    } catch(exception& e) {
        LOG("remotevobject", 2, "RemoteVobject::removeChild: caught exception from waitFor: " << e.what());
    }
}


void RemoteVobject::acquire()
{
    RefCounted::acquire();
    LOG("refcount", 5, "acquire called on " << getURL().getString() << " count is now " << getCount());
}

void RemoteVobject::release()
{
    LOG("refcount", 5, "release called on " << getURL().getString() << " count is now " << (getCount()-1));
    RefCounted::release();
}

---