vos/corelibs/vos/localvobject.cc

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

    Copyright (C) 2001-2003 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 "localvobject.hh"
#include "localsite.hh"
#include "listener.hh"
#include "message.hh"
#include "messageblock.hh"
#include "remotesite.hh"
#include "timer.hh"
#include "accesscontrol.hh"

using namespace VOS;

#include <stdio.h>
#include <math.h>

#include <string>
#include <algorithm>

/** @file
    Implements LocalVobject.
 */

LocalVobject::LocalVobject(const string& n, LocalSite* s, VobjectAccessControl* ac)
    :  VobjectImplementation(n, s, true)
{
    insertAccessControl(0, ac);

    addMessageHandler<LocalVobject>("core:find-child", this, &LocalVobject::findObjectHandler);
    addMessageHandler<LocalVobject>("core:get-types", this, &LocalVobject::getTypesHandler);
    addMessageHandler<LocalVobject>("core:get-parents", this, &LocalVobject::getParentsHandler);
    addMessageHandler<LocalVobject>("core:set-child", this, &LocalVobject::addChildHandler);
    addMessageHandler<LocalVobject>("core:insert-child", this, &LocalVobject::addChildHandler);
    addMessageHandler<LocalVobject>("core:remove-child", this, &LocalVobject::removeChildHandler);
    addMessageHandler<LocalVobject>("core:start-listening", this, &LocalVobject::startListeningHandler);
    addMessageHandler<LocalVobject>("core:stop-listening", this, &LocalVobject::stopListeningHandler);
    addMessageHandler<LocalVobject>("core:type-add", this, &LocalVobject::typeAddHandler);
}

void LocalVobject::initReply(Vobject* v, Message* reply, Message* m, const string& method)
{
    reply->setType("update");
    reply->setMethod(method);
    reply->setTo(m->getFrom());
    reply->setFrom(v->getURL().getString());
    reply->setNonce(m->getNonce());
}

void LocalVobject::sendMessage(MessageBlock* mb)
{
    pREF(MessageContext*, mc, new MessageContext(),
         for(int i = 0; i < mb->numMessages(); i++) {
             pREF(Message*, msg, mb->getMessage(i),
                  msg->setMessageContext(mc);
                  sendMessage(msg);
                 );
         }
        );
}

void LocalVobject::findObjectHandler(Message* m)
{
    vRef<Message> reply = new Message();
    initReply(this, &reply, m, "core:set-child-update");
    vRef<Site> mysite = getSite();
    bool thisIsSite = ((*mysite) == (*this));
    try {
        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        const ChildList& childrenX = getChildren();
        for(int i=0; i < m->getNumFields(); i++) {
            const Message::Field& f=m->getField(i);
            LOG("localvobject", 5, "path is " << f.value);
            if(f.key == "path") {
                if((i + 2) < m->getNumFields()
                   && m->getField(i+1).key == "to"
                   && m->getField(i+2).key == "path") {
                    try {
                        int pos1;
                        int pos2;
                        rREF(ParentChildRelation&, p, findChild(f.value), pos1 = p.position;);
                        rREF(ParentChildRelation&, p, findChild(m->getField(i+2).value), pos2 = p.position;);
                        if(pos1 > pos2) {
                            int tmp=pos2;
                            pos2=pos1;
                            pos1=tmp;
                        }
                        for(int n=pos1; n <= pos2; n++) {
                            vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ReadChild, *from, *this, n,
                                                                        childrenX[n]->contextual_name,
                                                                        *(childrenX[n]->child));
                            string errmessage;
                            if(validateAccess(*event, errmessage)) {
                                reply->insertField(-1, "pos", n);
                                reply->insertField(-1, "name", childrenX[n]->contextual_name);
                                reply->insertField(-1, "path", childrenX[n]->child->getURL().getString());
                                if(thisIsSite) {
                                    const TypeSet& ts = childrenX[n]->child->getTypes();
                                    if(ts.size()) {
                                        for(TypeSet::const_iterator ti = ts.begin(); ti != ts.end(); ti++) {
                                            reply->insertField(-1, "type", *ti);
                                        }
                                    } else {
                                        reply->insertField(-1, "type", "");
                                    }
                                }
                            } else {
                                reply->insertField(-1, "error", "Permission denied: " + errmessage);
                            }
                        }
                        i+=2;
                    } catch(NoSuchObjectError) {
                        reply->insertField(-1, "error", f.value);
                    }
                } else if(f.value.find("/") != string::npos) {
                } else {
                    try {
                        vRef<ParentChildRelation> c = findChild(f.value);

                        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ReadChild, *from, *this,
                                                                    c->position, c->contextual_name, *(c->child));

                        string errmessage;
                        if(validateAccess(*event, errmessage)) {
                            reply->insertField(-1, "pos", c->position);
                            reply->insertField(-1, "name", c->contextual_name);
                            reply->insertField(-1, "path", c->child->getURL().getString());
                            if(thisIsSite) {
                                const TypeSet& ts = c->child->getTypes();
                                if(ts.size()) {
                                    for(TypeSet::const_iterator ti = ts.begin(); ti != ts.end(); ti++) {
                                        reply->insertField(-1, "type", *ti);
                                    }
                                } else {
                                    reply->insertField(-1, "type", "");
                                }
                            }
                        } else {
                            reply->insertField(-1, "error", "Permission denied: " + errmessage);
                        }
                    } catch(NoSuchObjectError) {
                        reply->insertField(-1, "error", f.value);
                    }
                }
            }
        }
        from->sendMessage(&reply);
    } catch(Message::NoSuchFieldError) {
    }
}

void LocalVobject::getTypesHandler(Message* m)
{
    try {
        vRef<Message> reply = new Message();
        initReply(this, &reply, m, "core:type-add-update");

        for(set<string>::iterator i=types.begin(); i != types.end(); i++) {
            reply->insertField(-1, "type", *i);
        }

        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        from->sendMessage(&reply);
    } catch(NoSuchObjectError) {
    }
}

void LocalVobject::getParentsHandler(Message* m)
{
    try {
        vRef<Message> reply = new Message();
        initReply(this, &reply, m, "core:insert-parent-update");

        for(ParentSet::iterator i=parents.begin(); i != parents.end(); i++) {
            char pos[16];
            snprintf(pos, sizeof(pos), "%i", (*i)->position);
            reply->insertField(-1, "pos", string(pos));
            reply->insertField(-1, "name", (*i)->contextual_name);
            reply->insertField(-1, "path", (*i)->parent->getURL().getString());
        }

        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        from->sendMessage(&reply);
    } catch(NoSuchObjectError) {
    }
}

void LocalVobject::addChildHandler(Message* m)
{
    vRef<Message> reply = new Message();
    try {
        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        initReply(this, &reply, m, m->getMethod() + "-update");
        LOG("localvobject", 5, "setting up reply (0)");
        vRef<Site> st = m->getSourceSite();
        RemoteSite* fromsite = dynamic_cast<RemoteSite*>(&st);
        bool isListener = (childListeners.count(fromsite) != 0);
        if(isListener) childListeners.erase(fromsite);

        LOG("localvobject", 5, "set/insert-child creating reply " << m->getNumFields());

        for(int i=0; i < m->getNumFields(); i++) {
            if((i + 2) < m->getNumFields()) {
                const Message::Field& pos = m->getField(i);
                const Message::Field& name = m->getField(++i);
                const Message::Field& path = m->getField(++i);
                if(pos.key == "pos"
                   && name.key == "name"
                   && path.key == "path") {
                    int ipos=atoi(pos.value.c_str());
                    if(ipos < 0) ipos = ipos + (int)children.size() + 1;
                    ipos = ipos % ((int)children.size() + 1);

                    vRef<Vobject> newobj = findObject(path.value);
                    if(m->getMethod() == "core:set-child") {

                        if(children.size() == 0) {
                            reply->insertField(-1, "error", "permission to set " + path.value + " denied");
                            continue;
                        }

                        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ChildReplace, *from, *this, ipos,
                                                                    name.value, *newobj, *(children[ipos]->child));

                        string errmessage;
                        if(validateAccess(*event, errmessage)) {
                            try {
                                VobjectImplementation::setChild(&from, ipos, name.value, &newobj);
                            } catch(...) {
                                reply->insertField(-1, "error", "permission to set " + path.value + " denied");
                                continue;
                            }
                        } else {
                            reply->insertField(-1, "error", "Permission to set '" + path.value + "' denied: " + errmessage);
                            continue;
                        }
                    } else {
                        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ChildInsert, *from,
                                                                    *this, ipos, name.value, *newobj);
                        string errmessage;
                        if(validateAccess(*event, errmessage)) {
                            try {
                                VobjectImplementation::insertChild(&from, ipos, name.value, &newobj);
                            } catch(...) {
                                reply->insertField(-1, "error", "permission to set " + path.value + " denied");
                                continue;
                            }
                        } else {
                            reply->insertField(-1, "error", "Permission to add '" + path.value + "' denied: " + errmessage);
                            continue;
                        }
                    }
                    vRef<ParentChildRelation> r = findChild("#" + pos.value);
                    char x[16];
                    snprintf(x, sizeof(x), "%i", r->position);
                    reply->insertField(-1, "pos", string(x));
                    reply->insertField(-1, "name", r->contextual_name);
                    reply->insertField(-1, "path", r->child->getURL().getString());
                }
            }
        }

        if(isListener) childListeners.insert(fromsite);
        LOG("localvobject", 5, "about to send reply");
        from->sendMessage(&reply);
        LOG("localvobject", 5, "sent reply");
    } catch(NoSuchObjectError) {
    }
}

void LocalVobject::removeChildHandler(Message* m)
{
    vRef<Message> reply = new Message();
    try {
        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        initReply(this, &reply, m, "core:remove-child-update");
        vRef<Site> st = m->getSourceSite();
        RemoteSite* fromsite = dynamic_cast<RemoteSite*>(&st);
        bool isListener = (childListeners.count(fromsite) != 0);
        if(isListener) childListeners.erase(fromsite);

        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 ipos=atoi(pos.value.c_str());
                vRef<Vobject> pathobj = findObjectFromRoot(path.value);

                const string& ctxname = children[ipos]->contextual_name;
                Vobject* target = children[ipos]->child;

                vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ChildRemove, *from,
                                                            *this, ipos, ctxname, *target);

                string errmessage;
                if(ctxname == name.value
                   && *target == *pathobj
                   && validateAccess(*event, errmessage))
                {
                    VobjectImplementation::removeChild(&from, ipos);
                    reply->insertField(-1, "pos", pos.value);
                    reply->insertField(-1, "name", name.value);
                    reply->insertField(-1, "path", path.value);
                } else {
                    reply->insertField(-1, "error", "Permission to remove " + pos.value + " denied: " + errmessage);
                }
            } catch(NoSuchObjectError) {
                reply->insertField(-1, "error", "No such object path " + path.value);
            }
        }
        from->sendMessage(&reply);
        if(isListener) childListeners.insert(fromsite);
    } catch(NoSuchObjectError) {
    } catch(Message::NoSuchFieldError) {
    }
}

void LocalVobject::startListeningHandler(Message* m)
{
    try {
        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        vRef<Site> st = m->getSourceSite();
        RemoteSite* rs = dynamic_cast<RemoteSite*>(&st);

        if(rs) {
            for(int i = 0; i < m->getNumFields(); i++) {
                const Message::Field& f = m->getField(i);
                if(f.key == "listen") {
                    if(f.value == "types" || f.value == "children" || f.value == "parents"){
                        vRef<Message> reply = new Message();
                        initReply(this, &reply, m, "core:start-listening-reply");
                        reply->setNonce(m->getNonce() + string("-1"));
                        reply->insertField(-1, "listen", f.value);
                        from->sendMessage(&reply);
                    }

                    if(f.value == "types") {
                        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ReadType, *from, *this);
                        string errmessage;
                        if(validateAccess(*event, errmessage)) {
                            rs->lockTypeNotifyOutgoing(this);
                            addTypeListener(rs);
                            rs->unlockTypeNotifyOutgoing(this, m->getNonce());
                        }
                    } else if(f.value == "children") {
                        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ChildrenListen, *from, *this);
                        string errmessage;
                        if(validateAccess(*event, errmessage)) {
                            rs->lockChildNotifyOutgoing(this);
                            addChildListener(rs);
                            rs->unlockChildNotifyOutgoing(this, m->getNonce());
                        }
                    } else if(f.value == "parents") {
                        vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::ParentListen, *from, *this);

                        string errmessage;
                        if(validateAccess(*event, errmessage)) {
                            rs->lockParentNotifyOutgoing(this);
                            addParentListener(rs);
                            rs->unlockParentNotifyOutgoing(this, m->getNonce());
                        }
                    }
                }
            }
        }
    } catch(Message::NoSuchFieldError) { }
}

void LocalVobject::stopListeningHandler(Message* m)
{
    try {
        for(int i=0; i < m->getNumFields(); i++) {
            const Message::Field& f = m->getField(i);
            if(f.key == "listen") {
                vRef<Site> st = m->getSourceSite();
                RemoteSite* rs = dynamic_cast<RemoteSite*>(&st);
                if(rs) {
                    if(f.value == "types") {
                        removeTypeListener(rs);
                    } else if(f.value == "children") {
                        removeChildListener(rs);
                    } else if(f.value == "parents") {
                        removeParentListener(rs);
                    }
                }
            }
        }
    } catch(Message::NoSuchFieldError) { }
}

void LocalVobject::typeAddHandler(Message* m)
{
    try {
        vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
        for(int i=0; i < m->getNumFields(); i++) {
            const Message::Field& f = m->getField(i);
            if(f.key == "type") {
                vRef<VobjectEvent> event = new VobjectEvent(VobjectEvent::TypeInsert, *from, *this, f.value);

                string errmessage;
                if(validateAccess(*event, errmessage)) {
                    VobjectImplementation::addType(&from, f.value);

                    vRef<Message> reply = new Message();
                    initReply(this, &reply, m, "core:type-add-update");

                    reply->insertField(-1, "type", f.value);

                    vRef<Vobject> from = Vobject::findObjectFromRoot(m->getFrom());
                    from->sendMessage(&reply);
                }
            }
        }
    } catch(Message::NoSuchFieldError) { }
}


void LocalVobject::sendMessage(Message* m)
{
    LOG("LocalVobject::sendMessage", 5, "<<<(incoming)<<< sending to " << getURL().getString() << " ["
        << m->refcount_debug << "/" << m->getCount() << "]\n" << m->getFormattedString());

    LOG("localvobject", 5, "getting from (1) " << queueMsgs);

    // are we waiting for this nonce?
    /*if(waitForNonces.count(m->getNonce())) {
        m->acquire(); // released by: whoever calls LocalVobject::waitFor()
        waitForNonces[m->getNonce()]=m;
        }*/
    if(queueMsgs) {
        m->acquire(); // released by: whoever calls VobjectImplementation::receiveMessage()
        incomingMessageQueue.push_back(m);
    }

    if(m->getType() != "message") return;

    vRef<Vobject> to = findObjectFromRoot(m->getTo());
    if(&to != this) return;

    pair<HandlerMap::iterator, HandlerMap::iterator> hndls = msghandlers.equal_range(m->getMethod());
    for(HandlerMap::iterator i = hndls.first; i !=  hndls.second; i++) {
        (*i).second->sendMessage(m);
    }
}

Message* LocalVobject::waitFor(const string& nonce, RemoteSite* from, double timeout)
{
    bool prioritize=true;

    if(! from->isConnected()) {
        throw TimeoutError("remote site is not connected");
    }

    from->catchIncomingMessage(nonce);

    double now = getTimer();
    double timeoutAt = now + timeout;
    vRef<LocalSite> ls = dynamic_cast<LocalSite&>(getSite());
    double dmaxwait = ls->getTimeoutOnSelect();

    if(prioritize) ls->addPrioritizedNonce(nonce, from);
    try {
        while(true) {
            now = getTimer();
            if(now >= timeoutAt && !from->messageInProgress(nonce)) {
                from->clearCaughtMessage(nonce);
                ls->setTimeoutOnSelect(dmaxwait);
                LOG("localvobject", 3, "Timed out waiting for " << nonce);
                throw TimeoutError("waitFor timed out");
            }
            double waitLeft = timeoutAt - now;
            if(dmaxwait > 0.0) {
                if(dmaxwait < waitLeft) {
                    ls->setTimeoutOnSelect(dmaxwait);
                } else {
                    ls->setTimeoutOnSelect(waitLeft);
                }
            } else {
                ls->setTimeoutOnSelect(waitLeft);
            }

            try {
                ls->flushIncomingBuffers();
                if(from->messageReady(nonce)) {
                    if(Message* m = from->retrieveCaughtMessage(nonce)) {
                        vRef<Vobject> to = findObjectFromRoot(m->getTo());
                        if(&to == this) {
                            from->clearCaughtMessage(nonce);
                            ls->setTimeoutOnSelect(dmaxwait);
                            if(prioritize) ls->removePrioritizedNonce(nonce, from);
                            // pass reference through
                            return m;
                        }
                    }
                }
            } catch(MessageQueueEmptyError) {}
            if(! from->isConnected()) {
                ls->setTimeoutOnSelect(dmaxwait);
                LOG("localvobject", 3, "Timed out waiting for " << nonce);
                throw TimeoutError("remote site we were waiting on disconnected");
            }
        }
    } catch(...) {
        if(prioritize) ls->removePrioritizedNonce(nonce, from);
        throw;
    }
}

void LocalVobject::addType(const string& s)
{
    VobjectImplementation::addType(this, s);
}

void LocalVobject::setChild(int position, const string& contextual_name, Vobject* child)
    throw (AccessControlError, RemoteError)
{
    VobjectImplementation::setChild(this, position, contextual_name, child);
}

void LocalVobject::insertChild(int position, const string& contextual_name, Vobject* child)
    throw (AccessControlError, RemoteError)
{
    VobjectImplementation::insertChild(this, position, contextual_name, child);
}

void LocalVobject::removeChild(int position)
    throw (AccessControlError, RemoteError)
{
    VobjectImplementation::removeChild(this, position);
}



void LocalVobject::insertAccessControl(int pos, VobjectAccessControl* ac)
{
    if(pos < 0) pos += (int)accesscontrols.size() + 1;
    accesscontrols.insert(accesscontrols.begin() + pos, ac);
}

void LocalVobject::insertAccessControl(int pos, const string& policyname)
{
    if(pos < 0) pos += (int)accesscontrols.size() + 1;

    VobjectAccessControl* ac = VobjectAccessControl::getPolicy(policyname, this);
    if(ac) accesscontrols.insert(accesscontrols.begin() + pos, ac);
}

void LocalVobject::removeAccessControl(int pos)
{
    if(pos < 0) pos += (int)accesscontrols.size() + 1;
    accesscontrols.erase(accesscontrols.begin() + pos);
}

void LocalVobject::removeAccessControl(VobjectAccessControl* ac)
{
    for(unsigned int i = 0; i < accesscontrols.size(); i++) {
        if(accesscontrols[i] == ac) {
            accesscontrols.erase(accesscontrols.begin() + i);
            i--;
        }
    }
}

void LocalVobject::removeAccessControl(const string& policyname)
{
    for(unsigned int i = 0; i < accesscontrols.size(); i++) {
        if(accesscontrols[i]->getPolicyName() == policyname) {
            accesscontrols.erase(accesscontrols.begin() + i);
            i--;
        }
    }
}

const deque<VobjectAccessControl*>& LocalVobject::getAccessControls()
{
    return accesscontrols;
}

bool LocalVobject::validateAccess(VobjectEvent& e, string& message)
{
    if(accesscontrols.size() == 0) {
        message = "Error in access policy list.  Permission denied by default.";
        LOG("localvobject", 1, "Access policy list for "
            << e.getAffectedObject()->getURL().getString() << " is empty!");
        return false;
    }

    for(unsigned int i = 0; i < accesscontrols.size(); i++) {
        if(! accesscontrols[i]) {
            message = "Error in access policy list.  Permission denied by default.";
            LOG("localvobject", 1, "Access policy list "
                << e.getAffectedObject()->getURL().getString() << " contains an invalid (null) policy!");
            return false;
        }
        switch(e.getEvent()) {
        case VobjectEvent::TypeInsert:
            if(! accesscontrols[i]->checkAddTypePermission(e, message)) return false;
            break;
        case VobjectEvent::ChildInsert:
            if(! accesscontrols[i]->checkInsertChildPermission(e, message)) return false;
            break;
        case VobjectEvent::ChildReplace:
            if(! accesscontrols[i]->checkSetChildPermission(e, message)) return false;
            break;
        case VobjectEvent::ChildRemove:
            if(! accesscontrols[i]->checkRemoveChildPermission(e, message)) return false;
            break;
        case VobjectEvent::ReadChild:
            if(! accesscontrols[i]->checkReadChildPermission(e, message)) return false;
            break;
        case VobjectEvent::ReadParent:
            if(! accesscontrols[i]->checkReadParentPermission(e, message)) return false;
            break;
        case VobjectEvent::ReadType:
            if(! accesscontrols[i]->checkReadTypePermission(e, message)) return false;
            break;
        case VobjectEvent::ChildrenListen:
            if(! accesscontrols[i]->checkChildListenPermission(e, message)) return false;
            break;
        case VobjectEvent::ParentListen:
            if(! accesscontrols[i]->checkParentListenPermission(e, message)) return false;
            break;
        default:
            message = "Supplied validateAccess with an unsupported event type!";
            LOG("localvobject", 1, "Supplied validateAccess with an unsupported event type " << e.getEvent());
            return false;
        }
    }
    return true;
}

---