yarpbroker.cpp

Go to the documentation of this file.

/*
 * SPDX-FileCopyrightText: 2006-2021 Istituto Italiano di Tecnologia (IIT)
 * SPDX-License-Identifier: BSD-3-Clause
 */
 
#include <yarp/manager/yarpbroker.h>
 
#include <csignal>
#include <cstring>
 
#define YARPRUN_OK                  0
#define YARPRUN_NORESPONSE          1
#define YARPRUN_NOCONNECTION        2
#define YARPRUN_CONNECTION_TIMOUT   3
#define YARPRUN_SEMAPHORE_PARAM     4
#define YARPRUN_UNDEF               5
 
#define CONNECTION_TIMEOUT      2.0         //seconds
#define RUN_TIMEOUT             10.0        //seconds
#define STOP_TIMEOUT            15.0
#define KILL_TIMEOUT            10.0
#define EVENT_THREAD_PERIOD     0.5 //seconds
 
#if defined(_WIN32)
    #define SIGKILL 9
#endif
 
const char* yarprun_err_msg[] = { " (Ok) ",
                                  " (Remote host does not respond) ",
                                  " (Remote host does no exist) ",
                                  " (Timeout while connecting to the remote host) ",
                                  " (Blocked in broker semaphor) ",
                                  " (Undefined message) " };
 
using namespace yarp::os;
using namespace yarp::os::impl;
using namespace yarp::manager;
 
 
YarpBroker::YarpBroker() : PeriodicThread(EVENT_THREAD_PERIOD)
{
    bOnlyConnector = bInitialized = false;
    ID = generateID();
    strStdioUUID.clear();
}
 
 
YarpBroker::~YarpBroker()
{
    fini();
}
 
void YarpBroker::fini()
{
    if (PeriodicThread::isRunning()) {
        PeriodicThread::stop();
    }
    //port.close();
}
 
bool YarpBroker::init()
{
    //if(bInitialized)
    //  return true;
 
    if(!NetworkBase::checkNetwork(CONNECTION_TIMEOUT))
    {
        strError = "YARP network server is not up.";
        return false;
    }
    bInitialized = true;
    bOnlyConnector = true;
 
    /*
    semParam.wait();
    __trace_message = "(init) opening port ...";
    port.setTimeout(CONNECTION_TIMEOUT);
    port.open("...");
    __trace_message.clear();
    semParam.post();
    */
    return true;
}
 
bool YarpBroker::init(const char* szcmd, const char* szparam,
            const char* szhost, const char* szstdio,
            const char* szworkdir, const char* szenv )
{
    //if(bInitialized)
    //  return true;
 
    semParam.wait();
 
    strCmd.clear();
    strParam.clear();
    strHost.clear();
    strStdio.clear();
    strWorkdir.clear();
    strTag.clear();
    strEnv.clear();
 
    if(!szcmd)
    {
        strError = "command is not specified.";
        semParam.post();
        return false;
    }
 
    if(!szhost)
    {
        strError = "remote host port is not specified.";
        semParam.post();
        return false;
    }
 
    if (szhost[0] != '/') {
        strHost = std::string("/") + std::string(szhost);
    } else {
        strHost = szhost;
    }
 
    strCmd = szcmd;
    if (strlen(szparam)) {
        strParam = szparam;
    }
    if (strlen(szworkdir)) {
        strWorkdir = szworkdir;
    }
 
    if(strlen(szstdio))
    {
        if (szstdio[0] != '/') {
            strStdio = std::string("/") + std::string(szstdio);
        } else {
            strStdio = szstdio;
        }
    }
 
    if (strlen(szenv)) {
        strEnv = szenv;
    }
 
    OSTRINGSTREAM sstrID;
    sstrID<<(int)ID;
    strTag = strHost + strCmd + strParam + strEnv + sstrID.str();
    std::string::iterator itr;
    for (itr = strTag.begin(); itr != strTag.end(); itr++) {
        if (((*itr) == ' ') || ((*itr) == '/')) {
            (*itr) = ':';
        }
    }
 
   __trace_message = "(init) checking yarp network";
    if(!NetworkBase::checkNetwork(5.0))
    {
        strError = "YARP network server is not up.";
        __trace_message.clear();
        semParam.post();
        return false;
    }
    __trace_message = std::string("(init) checking existence of ") + strHost;
    if(!exists(strHost.c_str()))
    {
        strError = szhost;
        strError += " does not exist. check yarprun is running as server.";
        __trace_message.clear();
        semParam.post();
        return false;
    }
 
    /*
    port.setTimeout(CONNECTION_TIMEOUT);
    __trace_message = "(init) opening port ...";
    port.open("...");
    __trace_message.clear();
    */
 
    bInitialized = true;
    semParam.post();
 
    return true;
}
 
 
bool YarpBroker::start()
{
    if (!bInitialized) {
        return false;
    }
    if (bOnlyConnector) {
        return false;
    }
 
    strError.clear();
    int ret = requestServer(runProperty());
    if(ret != YARPRUN_OK)
    {
        strError = "cannot ask ";
        strError += strHost;
        strError += " to run ";
        strError += strCmd;
        strError += yarprun_err_msg[ret];
        if (ret == YARPRUN_SEMAPHORE_PARAM) {
            strError += std::string(" due to " + __trace_message);
        }
        return false;
    }
 
    double base = SystemClock::nowSystem();
    while(!timeout(base, RUN_TIMEOUT))
    {
        if(running() == 1)
        {
            if(strStdioUUID.size())
            {
                if (PeriodicThread::isRunning()) {
                    PeriodicThread::stop();
                }
                PeriodicThread::start();
            }
            return true;
        }
    }
 
    strError = "cannot run ";
    strError += strCmd;
    strError += " on ";
    strError += strHost;
    return false;
}
 
bool YarpBroker::stop()
{
    if (!bInitialized) {
        return true;
    }
    if (bOnlyConnector) {
        return false;
    }
 
    strError.clear();
    yarp::os::Bottle msg,grp,response;
 
    grp.clear();
    grp.addString("on");
    grp.addString(strHost.c_str());
    msg.addList()=grp;
    grp.clear();
    grp.addString("sigterm");
    grp.addString(strTag.c_str());
    msg.addList()=grp;
    int ret = SendMsg(msg, strHost, response, CONNECTION_TIMEOUT);
    if(ret != YARPRUN_OK)
    {
        strError = "cannot ask ";
        strError += strHost;
        strError += " to stop ";
        strError += strCmd;
        strError += yarprun_err_msg[ret];
        if (ret == YARPRUN_SEMAPHORE_PARAM) {
            strError += std::string(" due to " + __trace_message);
        }
        return false;
    }
 
    double base = SystemClock::nowSystem();
    while(!timeout(base, STOP_TIMEOUT))
    {
        if(running() == 0)
        {
            PeriodicThread::stop();
            return true;
        }
    }
 
    strError = "Timeout! Cannot stop ";
    strError += strCmd;
    strError += " on ";
    strError += strHost;
    PeriodicThread::stop();
    return false;
}
 
bool YarpBroker::kill()
{
    if (!bInitialized) {
        return true;
    }
    if (bOnlyConnector) {
        return false;
    }
 
    strError.clear();
 
    yarp::os::Bottle msg,grp,response;
    grp.clear();
    grp.addString("on");
    grp.addString(strHost.c_str());
    msg.addList() = grp;
    grp.clear();
    grp.addString("kill");
    grp.addString(strTag.c_str());
    grp.addInt32(SIGKILL);
    msg.addList() = grp;
    int ret = SendMsg(msg, strHost, response, CONNECTION_TIMEOUT);
    if(ret != YARPRUN_OK)
    {
        strError = "cannot ask ";
        strError += strHost;
        strError += " to kill ";
        strError += strCmd;
        strError += yarprun_err_msg[ret];
        if (ret == YARPRUN_SEMAPHORE_PARAM) {
            strError += std::string(" due to " + __trace_message);
        }
        return false;
    }
 
    double base = SystemClock::nowSystem();
    while(!timeout(base, KILL_TIMEOUT))
    {
        if(running() == 0)
        {
            PeriodicThread::stop();
            return true;
        }
    }
 
    strError = "cannot kill ";
    strError += strCmd;
    strError += " on ";
    strError += strHost;
    PeriodicThread::stop();
    return false;
}
 
 
int YarpBroker::running()
{
    if (!bInitialized) {
        return -1;
    }
    if (bOnlyConnector) {
        return -1;
    }
 
    strError.clear();
    yarp::os::Bottle msg,grp,response;
 
    grp.clear();
    grp.addString("on");
    grp.addString(strHost.c_str());
    msg.addList()=grp;
 
    grp.clear();
    grp.addString("isrunning");
    grp.addString(strTag.c_str());
    msg.addList()=grp;
 
    int ret = SendMsg(msg, strHost, response, 3.0);
    if(ret != YARPRUN_OK)
    {
        strError = "cannot ask ";
        strError += strHost;
        strError += " to check for status of ";
        strError += strCmd;
        strError += yarprun_err_msg[ret];
        if (ret == YARPRUN_SEMAPHORE_PARAM) {
            strError += std::string(" due to " + __trace_message);
        }
        return -1;
    }
    return ((response.get(0).asString() == "running")?1:0);
}
 
 
bool YarpBroker::attachStdout()
{
    return true;
}
 
void YarpBroker::detachStdout()
{
}
 
 
Property& YarpBroker::runProperty()
{
    command.clear();
    std::string cmd = strCmd + std::string(" ") + strParam;
    command.put("cmd", cmd);
    command.put("on", strHost);
    command.put("as", strTag);
    if (!strWorkdir.empty()) {
        command.put("workdir", strWorkdir);
    }
    if (!strStdio.empty()) {
        command.put("stdio", strStdio);
    }
    if (!strEnv.empty()) {
        command.put("env", strEnv);
    }
    //command.put("hold", "hold");
    return command;
}
 
 
bool YarpBroker::connect(const std::string& from, const std::string& to, const std::string& carrier, bool persist)
{
    if(from.empty())
    {
        strError = "no source port is introduced.";
        return false;
    }
 
    if(to.empty())
    {
        strError = "no destination port is introduced.";
        return false;
    }
 
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    style.carrier = carrier;
 
    if(!persist)
    {
        /*
         * TODO: this check should be removed and
         *       the necessary modification should be done inside NetworkBase::isConnected!!!
         */
        std::string strCarrier = carrier;
        bool needDisconnect = strCarrier.find("udp") == (size_t)0;
        needDisconnect |= strCarrier.find("mcast") == (size_t)0;
        if(needDisconnect == false) {
            if (NetworkBase::isConnected(from, to, style)) {
                return true;
            }
        }
 
        NetworkBase::connect(from, to, style);
        if(!connected(from, to, carrier))
        {
            strError = "cannot connect ";
            strError +=from;
            strError += " to " + std::string(to);
            return false;
        }
    }
    else
    {
        std::string topic = std::string("topic:/") + std::string(from) + std::string(to);
        NetworkBase::connect(from, topic, style);
        NetworkBase::connect(topic, to, style);
        if(!connected(from, to, carrier))
        {
            strError = "a persistent connection from ";
            strError +=from;
            strError += " to " + std::string(to);
            strError += " is created but not connected.";
            return false;
        }
 
    }
 
    return true;
}
 
bool YarpBroker::disconnect(const std::string& from, const std::string& to, const std::string& carrier)
{
 
    if(from.empty())
    {
        strError = "no source port is introduced.";
        return false;
    }
 
    if(to.empty())
    {
        strError = "no destination port is introduced.";
        return false;
    }
 
    /*
    if(!exists(from))
    {
        strError = from;
        strError += " does not exist.";
        return true;
    }
 
    if(!exists(to))
    {
        strError = to;
        strError += " does not exist.";
        return true;
    }
    */
 
    if (!connected(from, to, carrier)) {
        return true;
    }
 
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    style.carrier = carrier;
    if(!NetworkBase::disconnect(from, to, style))
    {
        strError = "cannot disconnect ";
        strError +=from;
        strError += " from " + std::string(to);
        return false;
    }
    return true;
 
}
 
bool YarpBroker::exists(const std::string& szport)
{
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    return NetworkBase::exists(szport, style);
}
 
std::string YarpBroker::requestRpc(const std::string& szport, const std::string& request, double timeout)
{
    if (szport.empty() || request.empty()) {
        return {};
    }
 
    if (!exists(szport)) {
        return {};
    }
 
    // opening the port
    yarp::os::Port port;
    port.setTimeout((float)((timeout>0.0) ? timeout : CONNECTION_TIMEOUT));
    if (!port.open("...")) {
        return {};
    }
 
    ContactStyle style;
    style.quiet = true;
    style.timeout = (timeout>0.0) ? timeout : CONNECTION_TIMEOUT;
    bool ret;
    for(int i=0; i<10; i++) {
        ret = NetworkBase::connect(port.getName(), szport, style);
        if (ret) {
            break;
        }
        SystemClock::delaySystem(1.0);
    }
 
    if(!ret) {
        port.close();
        return {};
    }
 
    Bottle msg, response;
    msg.fromString(request);
    ret = port.write(msg, response);
    NetworkBase::disconnect(port.getName(), szport);
    if(!response.size() || !ret) {
        port.close();
        return {};
    }
 
    port.close();
    return response.toString().c_str();
}
 
bool YarpBroker::connected(const std::string& from, const std::string& to, const std::string& carrier)
{
    if (!exists(from) || !exists(to)) {
        return false;
    }
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    style.carrier = carrier;
    return NetworkBase::isConnected(from, to, style);
}
 
bool YarpBroker::getSystemInfo(const std::string& server, SystemInfoSerializer& info)
{
    if (server.empty()) {
        return false;
    }
    if (!semParam.check()) {
        return false;
    }
 
    yarp::os::Port port;
    // opening the port
    port.setTimeout(CONNECTION_TIMEOUT);
    if(!port.open("...")) {
        __trace_message.clear();
        semParam.post();
        return false;
    }
 
    yarp::os::Bottle msg, grp;
    grp.clear();
    grp.addString("sysinfo");
    msg.addList() = grp;
 
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    //style.carrier = carrier;
 
 
    __trace_message = "(getSystemInfo) connecting to " + std::string(port.getName());
    bool connected = yarp::os::NetworkBase::connect(port.getName(), server, style);
    if(!connected)
    {
        port.close();
        strError = std::string("Cannot connect to ") + std::string(server);
        __trace_message.clear();
        semParam.post();
        return false;
    }
 
    __trace_message = "(getSystemInfo) writing to " + std::string(port.getName());
    bool ret = port.write(msg, info);
    __trace_message = "(getSystemInfo) disconnecting from " + std::string(port.getName());
    NetworkBase::disconnect(port.getName(), server);
 
    if(!ret)
    {
        port.close();
        strError = std::string(server) + std::string(" does not respond");
        __trace_message.clear();
        semParam.post();
        return false;
    }
 
    port.close();
    __trace_message.clear();
    semParam.post();
    return true;
}
 
bool YarpBroker::getAllPorts(std::vector<std::string> &ports)
{
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    Bottle cmd, reply;
    cmd.addString("list");
 
    bool ret = NetworkBase::writeToNameServer(cmd, reply, style);
    if (!ret)
    {
        strError = "Failed to reach name server\n";
        return false;
    }
 
    if ((reply.size() != 1) || (!reply.get(0).isString())) {
        return false;
    }
 
    std::string str = reply.get(0).asString();
    const char* delm = "registration name ";
    size_t pos1, pos2;
    while((pos1 = str.find(delm)) != std::string::npos)
    {
        str = str.substr(pos1+strlen(delm));
        if ((pos2 = str.find(' ')) != std::string::npos) {
            ports.push_back(str.substr(0, pos2));
        }
    }
 
    return true;
}
 
bool YarpBroker::getAllProcesses(const std::string& server,
                                 ProcessContainer& processes)
{
    if (server.empty()) {
        return false;
    }
 
    processes.clear();
    strError.clear();
    yarp::os::Bottle msg,grp,response;
 
    grp.clear();
    grp.addString("ps");
    msg.addList()=grp;
 
    int ret = SendMsg(msg, server, response, 3.0);
    if((ret == YARPRUN_OK) || (ret == YARPRUN_NORESPONSE))
    {
        for(size_t i=0; i<response.size(); i++)
        {
            Process proc;
            std::string sprc;
            if (response.get(i).check("pid")) {
                proc.pid = response.get(i).find("pid").asInt32();
            }
            if (response.get(i).check("cmd")) {
                sprc = response.get(i).find("cmd").asString();
            }
            if (response.get(i).check("env") && response.get(i).find("env").asString().length()) {
                sprc.append("; ").append(response.get(i).find("env").asString());
            }
            proc.command = sprc;
            processes.push_back(proc);
        }
        return true;
    }
 
    strError = "cannot ask ";
    strError += server;
    strError += " to give the list of running processes.";
    strError += yarprun_err_msg[ret];
    if (ret == YARPRUN_SEMAPHORE_PARAM) {
        strError += std::string(" due to " + __trace_message);
    }
    return false;
}
 
 
bool YarpBroker::rmconnect(const std::string& from, const std::string& to)
{
    std::string topic = from + to;
    Bottle cmd, reply;
    cmd.addString("untopic");
    cmd.addString(topic.c_str());
    return NetworkBase::write(NetworkBase::getNameServerContact(),
                                 cmd,
                                 reply,
                                 false,
                                 true,
                                 CONNECTION_TIMEOUT);
}
 
bool YarpBroker::setQos(const std::string& from, const std::string& to, const std::string& qosFrom, const std::string& qosTo)
{
    strError.clear();
 
    if (qosFrom.empty() && qosTo.empty()) {
        return true;
    }
 
    QosStyle styleFrom;
    QosStyle styleTo;
    if (qosFrom.empty() == false) {
        if(!getQosFromString(qosFrom, styleFrom)) {
            strError = "Error in parsing Qos properties of " + std::string(from);
            return false;
        }
    }
    if (qosTo.empty() == false) {
        if(!getQosFromString(qosTo, styleTo)) {
            strError = "Error in parsing Qos properties of " + std::string(to);
            return false;
        }
    }
    return NetworkBase::setConnectionQos(from, to, styleFrom, styleTo, true);
}
 
bool YarpBroker::getQosFromString(const std::string& qos, yarp::os::QosStyle& style)
{
    std::string strQos(qos);
    transform(strQos.begin(), strQos.end(), strQos.begin(),
              (int(*)(int))toupper);
    strQos.erase( std::remove_if( strQos.begin(), strQos.end(), ::isspace ), strQos.end() );
 
    //level:high; priority:10; policy:1
    std::stringstream ss(strQos); // Turn the string into a stream.
    std::string prop;
    while(getline(ss, prop, ';')) {
        size_t p = prop.find(':');
        if (p != prop.npos) {
            std::string key = prop.substr(0, p);
            std::string value = prop.substr(p+1);
            if (key.length() > 0 && value.length() > 0) {
                if (key == "LEVEL" || key=="DSCP" || key == "TOS") {
                    if (!style.setPacketPriority(prop)) {
                        return false;
                    }
                }
                else if (key == "PRIORITY") {
                    char* p;
                    int prio = strtol(value.c_str(), &p, 10);
                    style.setThreadPriority(prio);
                }
                else if (key == "POLICY") {
                    char* p;
                    int policy = strtol(value.c_str(), &p, 10);
                    style.setThreadPolicy(policy);
                }
            }
        }
    }
    return true;
}
 
std::string YarpBroker::error()
{
    return strError;
}
 
 
bool YarpBroker::timeout(double base, double timeout)
{
    SystemClock::delaySystem(1.0);
    if ((SystemClock::nowSystem() - base) > timeout) {
        return true;
    }
    return false;
}
 
bool YarpBroker::threadInit()
{
    if (!strStdioUUID.size()) {
        return false;
    }
 
    std::string strStdioPort = strStdioUUID + "/stdout";
    stdioPort.open("...");
 
    double base = SystemClock::nowSystem();
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
    while(!timeout(base, 5.0))
    {
        if (NetworkBase::connect(strStdioPort, stdioPort.getName(), style)) {
            return true;
        }
    }
 
    strError = "Cannot connect to stdio port ";
    strError += strStdioPort;
    stdioPort.close();
    return false;
}
 
 
void YarpBroker::run()
{
    Bottle *input;
    if( (input=stdioPort.read(false)) && eventSink)
    {
        for (size_t i = 0; i < input->size(); i++) {
            eventSink->onBrokerStdout(input->get(i).asString().c_str());
        }
    }
}
 
 
void YarpBroker::threadRelease()
{
    NetworkBase::disconnect(stdioPort.getName(), strStdioUUID);
    stdioPort.close();
}
 
 
int YarpBroker::SendMsg(Bottle& msg, std::string target, Bottle& response, float fTimeout)
{
    if (!exists(target.c_str())) {
        return YARPRUN_NOCONNECTION;
    }
 
    if (!semParam.check()) {
        return YARPRUN_SEMAPHORE_PARAM;
    }
 
    // opening the port
    yarp::os::Port port;
    port.setTimeout(fTimeout);
    if(!port.open("..."))
    {
        __trace_message.clear();
        semParam.post();
        return YARPRUN_CONNECTION_TIMOUT;
    }
 
    ContactStyle style;
    style.quiet = true;
    style.timeout = CONNECTION_TIMEOUT;
 
    bool ret;
    __trace_message = "(SendMsg) connecting to " + std::string(target);
    for(int i=0; i<10; i++)
    {
        ret = NetworkBase::connect(port.getName(), target, style);
        if (ret) {
            break;
        }
        SystemClock::delaySystem(1.0);
    }
 
    if(!ret)
    {
        port.close();
        __trace_message.clear();
        semParam.post();
        return YARPRUN_CONNECTION_TIMOUT;
    }
 
    __trace_message = "(SendMsg) writing to " + std::string(target);
    ret = port.write(msg, response);
    __trace_message = "(SendMsg) disconnecting from " + std::string(target);
    NetworkBase::disconnect(port.getName(),target);
    __trace_message.clear();
    semParam.post();
 
    if(!response.size() || !ret) {
        port.close();
        return YARPRUN_NORESPONSE;
    }
 
    port.close();
 
    return YARPRUN_OK;
}
 
 
int YarpBroker::requestServer(Property& config)
{
    yarp::os::Bottle msg;
 
    // USE A YARP RUN SERVER TO MANAGE STDIO
    //
    // client -> stdio server -> cmd server
    //
    if (config.check("cmd") && config.check("stdio"))
    {
        if (config.find("stdio").asString()=="") {return YARPRUN_UNDEF; }
        if (config.find("cmd").asString()=="")   {return YARPRUN_UNDEF; }
        if (!config.check("as") || config.find("as").asString()=="") { return YARPRUN_UNDEF; }
        if (!config.check("on") || config.find("on").asString()=="") { return YARPRUN_UNDEF; }
 
        msg.addList()=config.findGroup("stdio");
        msg.addList()=config.findGroup("cmd");
        msg.addList()=config.findGroup("as");
        msg.addList()=config.findGroup("on");
 
        if (config.check("workdir")) {
            msg.addList() = config.findGroup("workdir");
        }
        if (config.check("geometry")) {
            msg.addList() = config.findGroup("geometry");
        }
        if (config.check("hold")) {
            msg.addList() = config.findGroup("hold");
        }
        if (config.check("env")) {
            msg.addList() = config.findGroup("env");
        }
 
        Bottle response;
        int ret = SendMsg(msg, config.find("stdio").asString(),
                          response, CONNECTION_TIMEOUT);
        if (ret != YARPRUN_OK) {
            return ret;
        }
 
        if (response.size() > 2) {
            strStdioUUID = response.get(2).asString();
        }
 
        return ((response.get(0).asInt32()>0)?YARPRUN_OK:YARPRUN_UNDEF);
    }
 
    // DON'T USE A RUN SERVER TO MANAGE STDIO
    //
    // client -> cmd server
    //
    if (config.check("cmd"))
    {
        if (config.find("cmd").asString()=="")   { return YARPRUN_UNDEF; }
        if (!config.check("as") || config.find("as").asString()=="") {return YARPRUN_UNDEF; }
        if (!config.check("on") || config.find("on").asString()=="") {return YARPRUN_UNDEF; }
 
        msg.addList()=config.findGroup("cmd");
        msg.addList()=config.findGroup("as");
 
        if (config.check("workdir")) {
            msg.addList() = config.findGroup("workdir");
        }
        if (config.check("env")) {
            msg.addList() = config.findGroup("env");
        }
 
        Bottle response;
        int ret = SendMsg(msg, config.find("on").asString(),
                          response, CONNECTION_TIMEOUT);
        if (ret != YARPRUN_OK) {
            return ret;
        }
 
        return ((response.get(0).asInt32()>0)?YARPRUN_OK:YARPRUN_UNDEF);
    }
 
    return YARPRUN_UNDEF;
}