main.cpp

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/* 
 * Copyright (C) 2010 RobotCub Consortium, European Commission FP6 Project IST-004370
 * Author: Ugo Pattacini
 * email:  ugo.pattacini@iit.it
 * website: www.robotcub.org
 * Permission is granted to copy, distribute, and/or modify this program
 * under the terms of the GNU General Public License, version 2 or any
 * later version published by the Free Software Foundation.
 *
 * A copy of the license can be found at
 * http://www.robotcub.org/icub/license/gpl.txt
 *
 * 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
*/
 
#include <cstdio>
#include <cstdarg>
#include <mutex>
#include <sstream>
#include <string>
#include <map>
#include <deque>
 
#include <yarp/os/all.h>
 
using namespace std;
using namespace yarp::os;
 
#define CMD_ADD                         createVocab32('a','d','d')
#define CMD_DEL                         createVocab32('d','e','l')
#define CMD_GET                         createVocab32('g','e','t')
#define CMD_SET                         createVocab32('s','e','t')
#define CMD_LOCK                        createVocab32('l','o','c','k')
#define CMD_UNLOCK                      createVocab32('u','n','l','o')
#define CMD_OWNER                       createVocab32('o','w','n','e')
#define CMD_TIME                        createVocab32('t','i','m','e')
#define CMD_DUMP                        createVocab32('d','u','m','p')
#define CMD_ASK                         createVocab32('a','s','k')
#define CMD_SYNC                        createVocab32('s','y','n','c')
#define CMD_ASYNC                       createVocab32('a','s','y','n')
#define CMD_QUIT                        createVocab32('q','u','i','t')
#define CMD_BYE                         createVocab32('b','y','e')
                                        
#define REP_ACK                         createVocab32('a','c','k')
#define REP_NACK                        createVocab32('n','a','c','k')
#define REP_UNKNOWN                     createVocab32('u','n','k','n')
                                        
#define OPT_ALL                         createVocab32('a','l','l')
#define OPT_DISABLED                    (-1.0)
#define OPT_OWNERSHIP_ALL               ("all")
                                        
#define PROP_ID                         ("id")
#define PROP_LIFETIMER                  ("lifeTimer")
#define PROP_SET                        ("propSet")
#define BCTAG_EMPTY                     ("empty")
#define BCTAG_SYNC                      ("sync")
#define BCTAG_ASYNC                     ("async")
 
 
namespace relationalOperators
{
 
/************************************************************************/
bool alwaysTrue(Value &a, Value &b)
{
    return true;
}
 
 
/************************************************************************/
bool greater(Value &a, Value &b)
{
    if (a.isFloat64() && b.isFloat64())
        return (a.asFloat64()>b.asFloat64());
    else if (a.isInt32() && b.isInt32())
        return (a.asInt32()>b.asInt32());
    else
        return false;
}
 
 
/************************************************************************/
bool greaterEqual(Value &a, Value &b)
{
    if (a.isFloat64() && b.isFloat64())
        return (a.asFloat64()>=b.asFloat64());
    else if (a.isInt32() && b.isInt32())
        return (a.asInt32()>=b.asInt32());
    else
        return false;
}
 
 
/************************************************************************/
bool lower(Value &a, Value &b)
{
    if (a.isFloat64() && b.isFloat64())
        return (a.asFloat64()<b.asFloat64());
    else if (a.isInt32() && b.isInt32())
        return (a.asInt32()<b.asInt32());
    else
        return false;
}
 
 
/************************************************************************/
bool lowerEqual(Value &a, Value &b)
{
    if (a.isFloat64() && b.isFloat64())
        return (a.asFloat64()<=b.asFloat64());
    else if (a.isInt32() && b.isInt32())
        return (a.asInt32()<=b.asInt32());
    else
        return false;
}
 
 
/************************************************************************/
bool equal(Value &a, Value &b)
{
    if (a.isFloat64() && b.isFloat64())
        return (a.asFloat64()==b.asFloat64());
    else if (a.isInt32() && b.isInt32())
        return (a.asInt32()==b.asInt32());
    else if (a.isString() && b.isString())
    {
        string aStr=a.asString();
        string bStr=b.asString();
        return (aStr==bStr);
    }
    else
        return false;
}
 
 
/************************************************************************/
bool notEqual(Value &a, Value &b)
{
    if (a.isFloat64() && b.isFloat64())
        return (a.asFloat64()!=b.asFloat64());
    else if (a.isInt32() && b.isInt32())
        return (a.asInt32()!=b.asInt32());
    else if (a.isString() && b.isString())
    {
        string aStr=a.asString();
        string bStr=b.asString();
        return (aStr!=bStr);
    }
    else
        return false;
}
 
}
 
 
/************************************************************************/
class DataBase : public PeriodicThread
{
protected:
    /************************************************************************/
    struct Item
    {
        Property *prop;
        double    lastUpdate;
        string    owner;
 
        Item() : prop(NULL),
                 lastUpdate(OPT_DISABLED),
                 owner(OPT_OWNERSHIP_ALL) { }
    };
 
    /************************************************************************/
    struct Condition
    {
        string prop;
        bool (*compare)(Value&,Value&);
        Value val;
    };
 
    ResourceFinder *rf;
    map<int,Item> itemsMap;
    mutex mtx;
    int  idCnt;
    bool initialized;
    bool nosavedb;
    bool quitting;
 
    BufferedPort<Bottle> *pBroadcastPort;
    bool asyncBroadcast;
 
    /************************************************************************/
    void clear()
    {
        for (map<int,Item>::iterator it=itemsMap.begin(); it!=itemsMap.end(); it++)
            delete it->second.prop;
 
        itemsMap.clear();
    }
 
    /************************************************************************/
    void eraseItem(map<int,Item>::iterator &it)
    {
        delete it->second.prop;
        itemsMap.erase(it);
    }
 
    /************************************************************************/
    void write(FILE *stream)
    {
        int i=0;
        for (map<int,Item>::iterator it=itemsMap.begin(); it!=itemsMap.end(); it++)
            fprintf(stream,"item_%d (%s %d) (%s)\n",
                    i++,PROP_ID,it->first,it->second.prop->toString().c_str());
    }
 
    /************************************************************************/
    bool recursiveCheck(Property *item, deque<Condition> &condList,
                        deque<string> &opList, const unsigned int i=0)
    {
        bool result;
        if (item->check(condList[i].prop))
        {
            // take the current value of the item's property under test
            Value &val=item->find(condList[i].prop);
 
            // compute the condition over the current value
            result=(*condList[i].compare)(val,condList[i].val);
        }
        else
            result=false;
 
        if ((i+1)>=condList.size())
            return result;
        else if (opList[i]=="||")
            return (result||recursiveCheck(item,condList,opList,i+1));
        else    // at this point we know we deal with "&&" operations
        {
            unsigned int j;
            for (j=i+1; j<condList.size(); j++)
            {
                if (result)
                {
                    if (item->check(condList[j].prop))
                    {
                        Value &val=item->find(condList[j].prop);
                        result=result&&(*condList[j].compare)(val,condList[j].val);
                    }
                    else
                        result=false;
                }
 
                if (j<opList.size())
                    if (opList[j]=="||")
                        break;
            }
 
            if (j>=condList.size())
                return result;
            else
                return (result||recursiveCheck(item,condList,opList,j+1));
        }
    }
 
    /************************************************************************/
    void run()
    {
        broadcast(BCTAG_SYNC);
    }
 
public:
    /************************************************************************/
    DataBase() : PeriodicThread(1.0)
    {
        pBroadcastPort=NULL;
        asyncBroadcast=false;
        initialized=false;
        nosavedb=false;
        quitting=false;
        idCnt=0;
    }
 
    /************************************************************************/
    ~DataBase()
    {
        if (isRunning())
            stop();
 
        save();
        clear();
    }
 
    /************************************************************************/
    void configure(ResourceFinder &rf)
    {
        this->rf=&rf;
        if (initialized)
        {
            yWarning("database already initialized ...");
            return;
        }
 
        nosavedb=rf.check("no-save-db");
        if (!rf.check("no-load-db"))
            load();
 
        dump();
        initialized=true;
        yInfo("database ready ...");
 
        if (rf.check("sync-bc"))
        {
            setPeriod(rf.check("sync-bc",Value(1.0)).asFloat64());
            start();
        }
 
        asyncBroadcast=rf.check("async-bc");
    }
 
    /************************************************************************/
    void setBroadcastPort(BufferedPort<Bottle> &broadcastPort)
    {
        pBroadcastPort=&broadcastPort;
    }
 
    /************************************************************************/
    void load()
    {
        string dbFileName=rf->findFile("db");
        if (dbFileName.empty())
        {
            yWarning("requested database to be loaded not found!");
            return;
        }
 
        yInfo("loading database from %s ...",dbFileName.c_str());
 
        lock_guard<mutex> lck(mtx);
        clear();
        idCnt=0;
 
        Property finProperty;
        finProperty.fromConfigFile(dbFileName);
 
        Bottle finBottle; finBottle.read(finProperty);
        for (int i=0; i<finBottle.size(); i++)
        {
            ostringstream tag;
            tag<<"item_"<<i;
            Bottle &b1=finBottle.findGroup(tag.str());
 
            if (b1.isNull())
                continue;
 
            if (b1.size()<3)
            {
                yWarning("error while loading %s!",tag.str().c_str());
                continue;
            }
 
            Bottle *b2=b1.get(1).asList();
            Bottle *b3=b1.get(2).asList();
            if ((b2==NULL) || (b3==NULL))
            {
                yWarning("error while loading %s!",tag.str().c_str());
                continue;
            }
 
            if (b2->size()<2)
            {
                yWarning("error while loading %s!",tag.str().c_str());
                continue;
            }
 
            int id=b2->get(1).asInt32();
            itemsMap[id].prop=new Property(b3->toString().c_str());
 
            if (idCnt<=id)
                idCnt=id+1;
        }
 
        yInfo("database loaded");
    }
 
    /************************************************************************/
    void save()
    {
        if (nosavedb)
            return;
 
        lock_guard<mutex> lck(mtx);
        string dbFileName=rf->getHomeContextPath();
        dbFileName+="/";
        dbFileName+=rf->find("db").asString();
        yInfo("saving database in %s ...",dbFileName.c_str());
 
        FILE *fout=fopen(dbFileName.c_str(),"w");
        write(fout);
        fclose(fout);
 
        yInfo("database stored");
    }
 
    /************************************************************************/
    void dump()
    {
        lock_guard<mutex> lck(mtx);
        yInfo("dumping database content ...");
 
        if (itemsMap.size()==0)
            yInfo("empty");
        else
            write(stdout);
    }
 
    /************************************************************************/
    void broadcast(const string &type)
    {
        if (pBroadcastPort!=NULL)
        {
            if (pBroadcastPort->getOutputCount()>0)
            {
                lock_guard<mutex> lck(mtx);
                Bottle &bottle=pBroadcastPort->prepare();
                bottle.clear();
 
                bottle.addString(type);
                if (itemsMap.empty())
                    bottle.addString(BCTAG_EMPTY);
                else for (map<int,Item>::iterator it=itemsMap.begin(); it!=itemsMap.end(); it++)
                {
                    Bottle &item=bottle.addList();
                    item.read(*it->second.prop);
 
                    Bottle &idList=item.addList();
                    idList.addString(PROP_ID);
                    idList.addInt32(it->first);
                }
 
                pBroadcastPort->writeStrict();
            }
        }
    }
 
    /************************************************************************/
    bool add(Bottle *content)
    {
        if (content==NULL)
            return false;
 
        if (content->check(PROP_ID))
        {
            yWarning("%s field cannot be specified as a property!",PROP_ID);
            return false;
        }
 
        lock_guard<mutex> lck(mtx);
        itemsMap[idCnt].prop=new Property(content->toString().c_str());
        itemsMap[idCnt].lastUpdate=Time::now();
 
        return true;
    }
 
    /************************************************************************/
    bool remove(Bottle *content)
    {
        if (content==NULL)
            return false;
        
        if (content->size()==1)
        {
            if (content->get(0).isVocab32() || content->get(0).isString())
            {
                if (content->get(0).asVocab32()==OPT_ALL)
                {
                    lock_guard<mutex> lck(mtx);
                    clear();
                    yInfo("database cleared");
                    return true;
                }
            }
        }
 
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            Bottle *propSet=content->find(PROP_SET).asList();
            if (propSet!=NULL)
            {
                for (int i=0; i<propSet->size(); i++)
                    it->second.prop->unput(propSet->get(i).asString());
 
                it->second.lastUpdate=Time::now();
            }
            else
                eraseItem(it);
 
            return true;
        }
 
        return false;
    }
 
    /************************************************************************/
    bool get(Bottle *content, Bottle &response)
    {
        if (content==NULL)
            return false;
 
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            Property *pProp=it->second.prop;
            response.clear();
 
            Bottle *propSet=content->find(PROP_SET).asList();
            if (propSet!=NULL)
            {
                Property prop;
                for (int i=0; i<propSet->size(); i++)
                {
                    string propName=propSet->get(i).asString();
                    if (pProp->check(propName))
                        prop.put(propName,pProp->find(propName));
                }
 
                response.read(prop);
            }
            else
                response.read(*pProp);
 
            return true;
        }
 
        return false;
    }
 
    /************************************************************************/
    bool set(Bottle *content, const string &agent)
    {
        if (content==NULL)
            return false;
 
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            string owner=it->second.owner;
            if ((owner==OPT_OWNERSHIP_ALL) || (owner==agent))
            {
                Property *pProp=it->second.prop;
                for (int i=0; i<content->size(); i++)
                {
                    if (Bottle *option=content->get(i).asList())
                    {
                        if (option->size()<2)
                            continue;
 
                        string prop=option->get(0).asString();
                        Value  val=option->get(1);
 
                        if (prop==PROP_ID)
                            continue;
 
                        pProp->unput(prop);
                        pProp->put(prop,val);
                    }
                    else
                        continue;
                }
 
                it->second.lastUpdate=Time::now();
                return true;
            }
        }
 
        return false;
    }
 
    /************************************************************************/
    bool lock(Bottle *content, const string &agent)
    {
        if (content==NULL)
            return false;
 
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            string owner=it->second.owner;
            if ((owner==OPT_OWNERSHIP_ALL) || (owner==agent))
            {
                it->second.owner=agent;
                return true;
            }
        }
 
        return false;
    }
 
    /************************************************************************/
    bool unlock(Bottle *content, const string &agent)
    {
        if (content==NULL)
            return false;
 
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            string owner=it->second.owner;
            if ((owner==OPT_OWNERSHIP_ALL) || (owner==agent))
            {
                it->second.owner=OPT_OWNERSHIP_ALL;
                return true;
            }
        }
 
        return false;
    }
 
    /************************************************************************/
    bool owner(Bottle *content, Bottle &response)
    {
        if (content==NULL)
            return false;
        
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            response.clear();
            string &owner=it->second.owner;
            response.addString(owner);
            return true;
        }
 
        return false;
    }
 
    /************************************************************************/
    bool time(Bottle *content, Bottle &response)
    {
        if (content==NULL)
            return false;
        
        if (!content->check(PROP_ID))
        {
            yWarning("%s field not present within the request!",PROP_ID);
            return false;
        }
 
        int id=content->find(PROP_ID).asInt32();
 
        lock_guard<mutex> lck(mtx);
        map<int,Item>::iterator it=itemsMap.find(id);
        if (it!=itemsMap.end())
        {
            response.clear();
            if (it->second.lastUpdate<0.0)
                response.addFloat64(it->second.lastUpdate);
            else
            {
                double dt=Time::now()-it->second.lastUpdate;
                response.addFloat64(dt);
            }
            return true;
        }
 
        return false;
    }
 
    /************************************************************************/
    bool ask(Bottle *content, Bottle &response)
    {
        if (content==NULL)
            return false;
 
        lock_guard<mutex> lck(mtx);
        if (content->size()==1)
        {
            if (content->get(0).isVocab32() || content->get(0).isString())
            {
                if (content->get(0).asVocab32()==OPT_ALL)
                {
                    response.clear();
                
                    for (map<int,Item>::iterator it=itemsMap.begin(); it!=itemsMap.end(); it++)
                        response.addInt32(it->first);
 
                    return true;
                }
            }
        }
 
        deque<Condition> condList;
        deque<string>    opList;
 
        // we cannot accept a conditions string ending with
        // a boolean operator
        if (!(content->size()&0x01))
        {
            yWarning("uncorrect conditions received!");
            return false;
        }
 
        // parse the received conditions and build the lists
        for (int i=0; i<content->size(); i+=2)
        {
            if (Bottle *b=content->get(i).asList())
            {
                Condition condition;
                string operation;
 
                if (b->size()==1)
                {
                    condition.prop=b->get(0).asString();
                    condition.compare=&relationalOperators::alwaysTrue;
                }
                else if (b->size()>2)
                {
                    condition.prop=b->get(0).asString();
                    operation=b->get(1).asString();
                    condition.val=b->get(2);
 
                    if (operation==">")
                        condition.compare=&relationalOperators::greater;
                    else if (operation==">=")
                        condition.compare=&relationalOperators::greaterEqual;
                    else if (operation=="<")
                        condition.compare=&relationalOperators::lower;
                    else if (operation=="<=")
                        condition.compare=&relationalOperators::lowerEqual;
                    else if (operation=="==")
                        condition.compare=&relationalOperators::equal;
                    else if (operation=="!=")
                        condition.compare=&relationalOperators::notEqual;
                    else
                    {
                        yWarning("unknown relational operator '%s'!",operation.c_str());
                        return false;
                    }
                }
                else
                {
                    yWarning("wrong condition given!");
                    return false;
                }
 
                condList.push_back(condition);
 
                if ((i+1)<content->size())
                {
                    operation=content->get(i+1).asString();
                    if ((operation!="||") && (operation!="&&"))
                    {
                        yWarning("unknown boolean operator '%s'!",operation.c_str());
                        return false;
                    }
                    else
                        opList.push_back(operation);
                }
            }
            else
            {
                yWarning("wrong condition given!");
                return false;
            }
        }
 
        response.clear();
 
        // apply the conditions to each item
        for (map<int,Item>::iterator it=itemsMap.begin(); it!=itemsMap.end(); it++)
        {
            // do recursion and keep only the item that
            // satisfies the whole list of conditions
            if (recursiveCheck(it->second.prop,condList,opList))
                response.addInt32(it->first);
        }
 
        return true;
    }
 
    /************************************************************************/
    void periodicHandler(const double dt)   // manage the items life-timers
    {
        mtx.lock();
        bool erased=false;
        for (map<int,Item>::iterator it=itemsMap.begin(); it!=itemsMap.end(); it++)
        {
            Property *pProp=it->second.prop;
            if (pProp->check(PROP_LIFETIMER))
            {
                double lifeTimer=pProp->find(PROP_LIFETIMER).asFloat64()-dt;
                if (lifeTimer<=0.0)
                {
                    eraseItem(it);
                    erased=true;
                    break;
                }
                else
                {
                    pProp->unput(PROP_LIFETIMER);
                    pProp->put(PROP_LIFETIMER,lifeTimer);
                }
            }
        }
        mtx.unlock();
 
        if (asyncBroadcast && erased)
            broadcast(BCTAG_ASYNC);
    }
 
    /************************************************************************/
    bool isQuitting() const
    {
        return quitting;
    }
 
    /************************************************************************/
    void respond(ConnectionReader &connection, const Bottle &command, Bottle &reply)
    {
        string agent=connection.getRemoteContact().getName();
        if (command.size()<1)
        {
            reply.addVocab32(REP_NACK);
            return;
        }
 
        reply.clear();
        int cmd=command.get(0).asVocab32();
        switch(cmd)
        {
            //-----------------
            case CMD_ADD:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle *content=command.get(1).asList();
                if (add(content))
                {
                    reply.addVocab32(REP_ACK);
                    Bottle &b=reply.addList();
                    b.addString(PROP_ID);
                    b.addInt32(idCnt);
                    idCnt++;
 
                    if (asyncBroadcast)
                        broadcast(BCTAG_ASYNC);
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_DEL:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle *content=command.get(1).asList();
                if (remove(content))
                {
                    reply.addVocab32(REP_ACK);
                    if (asyncBroadcast)
                        broadcast(BCTAG_ASYNC);
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_GET:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle response;
                Bottle *content=command.get(1).asList();
                if (get(content,response))
                {
                    reply.addVocab32(REP_ACK);
                    reply.addList()=response;
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_SET:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
    
                Bottle *content=command.get(1).asList();
                if (set(content,agent))
                {
                    reply.addVocab32(REP_ACK);
                    if (asyncBroadcast)
                        broadcast(BCTAG_ASYNC);
                }
                else
                    reply.addVocab32(REP_NACK);
    
                break;
            }
 
            //-----------------
            case CMD_LOCK:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle *content=command.get(1).asList();
                if (lock(content,agent))
                    reply.addVocab32(REP_ACK);
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_UNLOCK:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle *content=command.get(1).asList();
                if (unlock(content,agent))
                    reply.addVocab32(REP_ACK);
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_OWNER:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle response;
                Bottle *content=command.get(1).asList();
                if (owner(content,response))
                {
                    reply.addVocab32(REP_ACK);
                    reply.addList()=response;
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_TIME:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle response;
                Bottle *content=command.get(1).asList();
                if (time(content,response))
                {
                    reply.addVocab32(REP_ACK);
                    reply.addList()=response;
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_DUMP:
            {
                dump();
                reply.addVocab32(REP_ACK);
                break;
            }
 
            //-----------------
            case CMD_SYNC:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                int opt=command.get(1).asVocab32();
                if (opt==Vocab32::encode("start"))
                {
                    if (command.size()>=3)
                        setPeriod(command.get(2).asFloat64());
 
                    if (!isRunning())
                        start();
                    else if (isSuspended())
                        resume();
 
                    reply.addVocab32(REP_ACK);
                }
                else if (opt==Vocab32::encode("stop"))
                {
                    if (isRunning() && !isSuspended())
                        suspend();
 
                    reply.addVocab32(REP_ACK);
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_ASYNC:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                int opt=command.get(1).asVocab32();
                if (opt==Vocab32::encode("on"))
                {
                    asyncBroadcast=true;
                    reply.addVocab32(REP_ACK);
                }
                else if (opt==Vocab32::encode("off"))
                {
                    asyncBroadcast=false;
                    reply.addVocab32(REP_ACK);
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_ASK:
            {
                if (command.size()<2)
                {
                    reply.addVocab32(REP_NACK);
                    break;
                }
 
                Bottle response;
                Bottle *content=command.get(1).asList();
                if (ask(content,response))
                {
                    reply.addVocab32(REP_ACK);
                    Bottle &b=reply.addList();
                    b.addString(PROP_ID);
                    b.addList()=response;
                }
                else
                    reply.addVocab32(REP_NACK);
 
                break;
            }
 
            //-----------------
            case CMD_QUIT:
            case CMD_BYE:
            {
                quitting=true;
                reply.addVocab32(REP_ACK);
                break;
            }
 
            //-----------------
            default:
            {
                yWarning("received unknown command!");
                reply.addVocab32(REP_UNKNOWN);
            }
        }
    }
 
    /************************************************************************/
    bool modify(const Bottle &content)
    {
        if (content.size()==0)
            return false;
 
        string type=content.get(0).asString();
        if ((type!=BCTAG_EMPTY) && (type!=BCTAG_SYNC) && (type!=BCTAG_ASYNC))
            return false;
 
        mtx.lock();
        clear();
 
        if (type!=BCTAG_EMPTY)
        {
            idCnt=0;
            for (int i=1; i<content.size(); i++)
            {
                if (Bottle *item=content.get(i).asList())
                {
                    if (Bottle *idList=item->get(0).asList())
                    {
                        if (idList->size()==2)
                        {
                            if (idList->get(0).asString()==PROP_ID)
                            {
                                int id=idList->get(1).asInt32();
                                itemsMap[id].prop=new Property(item->tail().toString().c_str());
 
                                if (idCnt<=id)
                                    idCnt=id+1;
                            }
                        }
                    }
                }
            }
        }
 
        mtx.unlock();
 
        if (asyncBroadcast)
            broadcast(BCTAG_ASYNC);
 
        return true;
    }
};
 
 
/************************************************************************/
class RpcProcessor : public PortReader
{
protected:
    DataBase *pDataBase;
    unsigned int nCalls;
    double cumTime;
 
    /************************************************************************/
    bool read(ConnectionReader &connection)
    {
        Bottle command;
        if (!command.read(connection) || (pDataBase==NULL))
            return false;
 
        Bottle reply;
        double t0=Time::now();
        pDataBase->respond(connection,command,reply);
        cumTime+=Time::now()-t0;
        nCalls++;
 
        if (ConnectionWriter *writer=connection.getWriter())
            reply.write(*writer);
 
        return true;
    }
 
public:
    /************************************************************************/
    RpcProcessor()
    {
        pDataBase=NULL;
        nCalls=0;
        cumTime=0.0;
    }
 
    /************************************************************************/
    void setDataBase(DataBase &dataBase)
    {
        pDataBase=&dataBase;
    }
 
    /************************************************************************/
    void getStats(unsigned int &nCalls, double &cumTime) const
    {
        nCalls=this->nCalls;
        cumTime=this->cumTime;
    }
};
 
 
/************************************************************************/
class DataBaseModifyPort : public BufferedPort<Bottle>
{
protected:
    DataBase *pDataBase;
 
    /************************************************************************/
    void onRead(Bottle &content)
    {
        if (pDataBase!=NULL)
            pDataBase->modify(content);
    }
 
public:
    /************************************************************************/
    DataBaseModifyPort() : pDataBase(NULL) { }
 
    /************************************************************************/
    void setDataBase(DataBase &dataBase)
    {
        pDataBase=&dataBase;
    }
};
 
 
/************************************************************************/
class objectsPropertiesCollectorModule: public RFModule
{
private:
    DataBase             dataBase;
    RpcProcessor         rpcProcessor;
    DataBaseModifyPort   modifyPort;
    RpcServer            rpcPort;
    BufferedPort<Bottle> bcPort;
 
    int cnt;
    bool stats;
    unsigned int nCallsOld;
    double cumTimeOld;
 
public:
    /************************************************************************/
    bool configure(ResourceFinder &rf)
    {
        dataBase.configure(rf);
        stats=rf.check("stats");
 
        string name=rf.check("name",Value("objectsPropertiesCollector")).asString();
        dataBase.setBroadcastPort(bcPort);
        rpcProcessor.setDataBase(dataBase);
        rpcPort.setReader(rpcProcessor);
        modifyPort.setDataBase(dataBase);
        modifyPort.useCallback();
        rpcPort.open("/"+name+"/rpc");
        bcPort.open("/"+name+"/broadcast:o");
        modifyPort.open("/"+name+"/modify:i");
 
        cnt=0;
        nCallsOld=0;
        cumTimeOld=0.0;
 
        return true;
    }
 
    /************************************************************************/
    bool close()
    {
        modifyPort.disableCallback();
        dataBase.stop();
 
        rpcPort.interrupt();
        bcPort.interrupt();
        modifyPort.interrupt();
 
        rpcPort.close();
        bcPort.close();
        modifyPort.close();
 
        return true;
    }
 
    /************************************************************************/
    bool updateModule()
    {
        dataBase.periodicHandler(getPeriod());
 
        // back-up straightaway the database each 15 minutes
        if ((++cnt)*getPeriod()>(15.0*60.0))
        {
            dataBase.save();
            cnt=0;
        }
 
        if (stats)
        {
            unsigned int nCalls; double cumTime;
            rpcProcessor.getStats(nCalls,cumTime);
 
            unsigned int calls=nCalls-nCallsOld;
            double timeSpent=cumTime-cumTimeOld;
            yInfo("*** Statistics: received %d/%g [requests/s]; %g [ms/request] spent on average",
                  calls,getPeriod(),timeSpent==0.0?0.0:(1e3*timeSpent)/(double)calls);
 
            nCallsOld=nCalls;
            cumTimeOld=cumTime;
        }
 
        return !dataBase.isQuitting();
    }
 
    /************************************************************************/
    double getPeriod()
    {
        return 1.0;
    }
};
 
 
/************************************************************************/
int main(int argc, char *argv[])
{
    Network yarp;
 
    ResourceFinder rf;
    rf.setDefaultContext("objectsPropertiesCollector");
    rf.setDefault("db","dataBase.ini");
    rf.configure(argc,argv);
 
    if (rf.check("help"))
    {
        printf("Options\n");
        printf("\t--name        <name>: collector name (default: objectsPropertiesCollector)\n");
        printf("\t--db      <fileName>: database file name to load at startup/save at shutdown (default: dataBase.ini)\n");
        printf("\t--context  <context>: context to search for database file (default: objectsPropertiesCollector)\n");
        printf("\t--no-load-db        : start an empty database\n");
        printf("\t--no-save-db        : prevent from saving the content of database at shutdown\n");
        printf("\t--sync-bc        <T>: broadcast the database content each T seconds\n");
        printf("\t--async-bc          : broadcast the database content whenever a change occurs\n");
        printf("\t--stats             : enable statistics printouts\n");
        printf("\n");
        return 0;
    }
 
    if (!yarp.checkNetwork())
    {
        yError("YARP server not available!");
        return 1;
    }
 
    objectsPropertiesCollectorModule collector;
    return collector.runModule(rf);
}