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asebaros.cpp

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#include "asebaros.h"

#include <aseba/compiler/compiler.h>

#include <ros/console.h>

#include <vector>
#include <sstream>
#include <boost/format.hpp>

#include <libxml/parser.h>
#include <libxml/tree.h>


using namespace asebaros;
using namespace std;
using namespace boost;
using namespace Dashel;
using namespace Aseba;

// UTF8 to wstring
std::wstring widen(const char *src)
{
        const size_t destSize(mbstowcs(0, src, 0)+1);
        std::vector<wchar_t> buffer(destSize, 0);
        mbstowcs(&buffer[0], src, destSize);
        return std::wstring(buffer.begin(), buffer.end() - 1);
}
std::wstring widen(const std::string& src)
{
        return widen(src.c_str());
}

// wstring to UTF8
std::string narrow(const wchar_t* src)
{
        const size_t destSize(wcstombs(0, src, 0)+1);
        std::vector<char> buffer(destSize, 0);
        wcstombs(&buffer[0], src, destSize);
        return std::string(buffer.begin(), buffer.end() - 1);
}
std::string narrow(const std::wstring& src)
{
        return narrow(src.c_str());
}


// AsebaDashelHub

AsebaDashelHub::AsebaDashelHub(AsebaROS* asebaROS, unsigned port, bool forward):
        Dashel::Hub(),
        asebaROS(asebaROS),
        forward(forward)
{
        ostringstream oss;
        oss << "tcpin:port=" << port;
        Dashel::Hub::connect(oss.str());
}

static wstring asebaMsgToString(Message *message)
{
        wostringstream oss;
        message->dump(oss);
        return oss.str();
}

void AsebaDashelHub::sendMessage(Message *message, bool doLock, Stream* sourceStream)
{
        // dump if requested
        // TODO: put a request for unicode version of ROS debug
        ROS_DEBUG_STREAM("sending aseba message: " << narrow(asebaMsgToString(message)));
        
        // Might be called from the ROS thread, not the Hub thread, need to lock
        if (doLock)
                lock();

        // write on all connected streams
        for (StreamsSet::iterator it = dataStreams.begin(); it != dataStreams.end();++it)
        {
                Stream* destStream(*it);
                
                if ((forward) && (destStream == sourceStream))
                        continue;
                
                try
                {
                        message->serialize(destStream);
                        destStream->flush();
                }
                catch (DashelException e)
                {
                        // if this stream has a problem, ignore it for now, and let Hub call connectionClosed later.
                        ROS_ERROR("error while writing message");
                }
        }

        if (doLock)
                unlock();
}

void AsebaDashelHub::operator()()
{
        Hub::run();
        //cerr << "hub returned" << endl;
        ros::shutdown();
}

void AsebaDashelHub::startThread()
{
        thread = new boost::thread(ref(*this));
}

void AsebaDashelHub::stopThread()
{
        Hub::stop();
        thread->join();
        delete thread;
        thread = 0;
}

// the following method run in the blocking reception thread
        
void AsebaDashelHub::incomingData(Stream *stream)
{
        // receive message
        Message *message = 0;
        try
        {
                message = Message::receive(stream);
        }
        catch (DashelException e)
        {
                // if this stream has a problem, ignore it for now, and let Hub call connectionClosed later.
                ROS_ERROR("error while writing message");
        }
        
        // send message to Dashel peers
        sendMessage(message, false, stream);
        
        // process message for ROS peers, the receiver will delete it
        asebaROS->processAsebaMessage(message);
        
        // free the message
        delete message;
}

void AsebaDashelHub::connectionCreated(Stream *stream)
{
        ROS_INFO_STREAM("Incoming connection from " << stream->getTargetName());
        
        if (dataStreams.size() == 1)
        {
                // Note: on some robot such as the marXbot, because of hardware
                // constraints this might not work. In this case, an external
                // hack is required
                GetDescription getDescription;
                sendMessage(&getDescription, false);
        }
}

void AsebaDashelHub::connectionClosed(Stream* stream, bool abnormal)
{
        if (abnormal)
                ROS_INFO_STREAM("Abnormal connection closed to " << stream->getTargetName() << " : " << stream->getFailReason());
        else
                ROS_INFO_STREAM("Normal connection closed to " << stream->getTargetName());
}


// AsebaROS

bool AsebaROS::loadScript(LoadScripts::Request& req, LoadScripts::Response& res)
{
        // locking: in this method, we lock access to the object's members
        
        // open document
        const string& fileName(req.fileName);
        xmlDoc *doc = xmlReadFile(fileName.c_str(), NULL, 0);
        if (!doc)
        {
                ROS_ERROR_STREAM("Cannot read XML from file " << fileName);
                return false;
        }
    xmlNode *domRoot = xmlDocGetRootElement(doc);
        
        // clear existing data
        mutex.lock();
        commonDefinitions.events.clear();
        commonDefinitions.constants.clear();
        userDefinedVariablesMap.clear();
        pubs.clear();
        subs.clear();
        mutex.unlock();
        
        // load new data
        int noNodeCount = 0;
        bool wasError = false;
        if (!xmlStrEqual(domRoot->name, BAD_CAST("network")))
        {
                ROS_ERROR("root node is not \"network\", XML considered as invalid");
                wasError = true;
        }
        else for (xmlNode *domNode = xmlFirstElementChild(domRoot); domNode; domNode = domNode->next)
        {
                //cerr << "node " << domNode->name << endl;
                if (domNode->type == XML_ELEMENT_NODE)
                {
                        if (xmlStrEqual(domNode->name, BAD_CAST("node")))
                        {
                                // get attributes, child and content
                                xmlChar *name = xmlGetProp(domNode, BAD_CAST("name"));
                                if (!name)
                                        ROS_WARN("missing \"name\" attribute in \"node\" entry");
                                else
                                {
                                        const string _name((const char *)name);
                                        xmlChar * text = xmlNodeGetContent(domNode);
                                        if (!text)
                                                ROS_WARN("missing text in \"node\" entry");
                                        else
                                        {
                                                //cerr << text << endl;
                                                unsigned preferedId(0);
                                                xmlChar *storedId = xmlGetProp(domNode, BAD_CAST("nodeId"));
                                                if (storedId)
                                                        preferedId = unsigned(atoi((char*)storedId));
                                                mutex.lock();
                                                bool ok;
                                                unsigned nodeId(DescriptionsManager::getNodeId(widen(_name), preferedId, &ok));
                                                mutex.unlock();
                                                if (ok)
                                                {
                                                        mutex.lock();
                                                        // compile code
                                                        std::wistringstream is(widen((const char *)text));
                                                        Error error;
                                                        BytecodeVector bytecode;
                                                        unsigned allocatedVariablesCount;
                                                        
                                                        Compiler compiler;
                                                        compiler.setTargetDescription(getDescription(nodeId));
                                                        compiler.setCommonDefinitions(&commonDefinitions);
                                                        bool result = compiler.compile(is, bytecode, allocatedVariablesCount, error);
                                                        mutex.unlock();
                                                        
                                                        if (result)
                                                        {
                                                                typedef std::vector<Message*> MessageVector;
                                                                MessageVector messages;
                                                                sendBytecode(messages, nodeId, std::vector<uint16>(bytecode.begin(), bytecode.end()));
                                                                for (MessageVector::const_iterator it = messages.begin(); it != messages.end(); ++it)
                                                                {
                                                                        hub.sendMessage(*it, true);
                                                                        delete *it;
                                                                }
                                                                Run msg(nodeId);
                                                                hub.sendMessage(&msg, true);
                                                                // retrieve user-defined variables for use in get/set
                                                                mutex.lock();
                                                                userDefinedVariablesMap[_name] = *compiler.getVariablesMap();
                                                                mutex.unlock();
                                                        }
                                                        else
                                                        {
                                                                ROS_ERROR_STREAM("compilation of " << fileName << ", node " << _name << " failed: " << narrow(error.toWString()));
                                                                wasError = true;
                                                        }
                                                }
                                                else
                                                        noNodeCount++;
                                                
                                                // free attribute and content
                                                xmlFree(text);
                                        }
                                        xmlFree(name);
                                }
                        }
                        else if (xmlStrEqual(domNode->name, BAD_CAST("event")))
                        {
                                // get attributes
                                xmlChar *name = xmlGetProp(domNode, BAD_CAST("name"));
                                if (!name)
                                        ROS_WARN("missing \"name\" attribute in \"event\" entry");
                                xmlChar *size = xmlGetProp(domNode, BAD_CAST("size")); 
                                if (!size)
                                        ROS_WARN("missing \"size\" attribute in \"event\" entry");
                                // add event
                                if (name && size)
                                {
                                        int eventSize(atoi((const char *)size));
                                        if (eventSize > ASEBA_MAX_EVENT_ARG_SIZE)
                                        {
                                                ROS_ERROR("Event %s has a length %d larger than maximum %d", name, eventSize, ASEBA_MAX_EVENT_ARG_SIZE);
                                                wasError = true;
                                                break;
                                        }
                                        else
                                        {
                                                lock_guard<boost::mutex> lock(mutex);
                                                commonDefinitions.events.push_back(NamedValue(widen((const char *)name), eventSize));
                                        }
                                }
                                // free attributes
                                if (name)
                                        xmlFree(name);
                                if (size)
                                        xmlFree(size);
                        }
                        else if (xmlStrEqual(domNode->name, BAD_CAST("constant")))
                        {
                                // get attributes
                                xmlChar *name = xmlGetProp(domNode, BAD_CAST("name"));
                                if (!name)
                                        ROS_WARN("missing \"name\" attribute in \"constant\" entry");
                                xmlChar *value = xmlGetProp(domNode, BAD_CAST("value")); 
                                if (!value)
                                        ROS_WARN("missing \"value\" attribute in \"constant\" entry");
                                // add constant if attributes are valid
                                if (name && value)
                                {
                                        lock_guard<boost::mutex> lock(mutex);
                                        commonDefinitions.constants.push_back(NamedValue(widen((const char *)name), atoi((const char *)value)));
                                }
                                // free attributes
                                if (name)
                                        xmlFree(name);
                                if (value)
                                        xmlFree(value);
                        }
                        else
                                ROS_WARN_STREAM("Unknown XML node seen in .aesl file: " << domNode->name);
                }
        }

        // release memory
        xmlFreeDoc(doc);
        
        // check if there was an error
        if (wasError)
        {
                ROS_ERROR_STREAM("There was an error while loading script " << fileName);
                mutex.lock();
                commonDefinitions.events.clear();
                commonDefinitions.constants.clear();
                userDefinedVariablesMap.clear();
                mutex.unlock();
        }
        
        // check if there was some matching problem
        if (noNodeCount)
        {
                ROS_WARN_STREAM(noNodeCount << " scripts have no corresponding nodes in the current network and have not been loaded.");
        }
        
        // recreate publishers and subscribers
        mutex.lock();
        typedef EventsDescriptionsVector::const_iterator EventsDescriptionsConstIt;
        for (size_t i = 0; i < commonDefinitions.events.size(); ++i)
        {
                const wstring& name(commonDefinitions.events[i].name);
                pubs.push_back(n.advertise<AsebaEvent>(narrow(L"events/"+name), 100));
                subs.push_back(n.subscribe<AsebaEvent>(narrow(L"events/"+name), 100, bind(&AsebaROS::knownEventReceived, this, i, _1)));
        }
        mutex.unlock();
        
        return true;
}

bool AsebaROS::getNodeList(GetNodeList::Request& req, GetNodeList::Response& res)
{
        lock_guard<boost::mutex> lock(mutex);
        
        transform(nodesNames.begin(), nodesNames.end(), back_inserter(res.nodeList), bind(&NodesNamesMap::value_type::first,_1));
        return true;
}

bool AsebaROS::getNodeId(GetNodeId::Request& req, GetNodeId::Response& res)
{
        lock_guard<boost::mutex> lock(mutex);
        
        NodesNamesMap::const_iterator nodeIt(nodesNames.find(req.nodeName));
        if (nodeIt != nodesNames.end())
        {
                res.nodeId = nodeIt->second;
                return true;
        }
        else
        {
                ROS_ERROR_STREAM("node " << req.nodeName << " does not exists");
                return false;
        }
}

bool AsebaROS::getNodeName(GetNodeName::Request& req, GetNodeName::Response& res)
{
        lock_guard<boost::mutex> lock(mutex);
        
        NodesDescriptionsMap::const_iterator nodeIt(nodesDescriptions.find(req.nodeId));
        if (nodeIt != nodesDescriptions.end())
        {
                res.nodeName = narrow(nodeIt->second.name);
                return true;
        }
        else
        {
                ROS_ERROR_STREAM("node " << req.nodeId << " does not exists");
                return false;
        }
}

struct ExtractNameVar
{
        string operator()(const std::pair<std::wstring, std::pair<unsigned, unsigned> > p) const { return narrow(p.first); }
};

struct ExtractNameDesc
{
        string operator()(const TargetDescription::NamedVariable& nv) const { return narrow(nv.name); }
};

bool AsebaROS::getVariableList(GetVariableList::Request& req, GetVariableList::Response& res)
{
        lock_guard<boost::mutex> lock(mutex);
        
        NodesNamesMap::const_iterator nodeIt(nodesNames.find(req.nodeName));
        if (nodeIt != nodesNames.end())
        {
                // search if we have a user-defined variable map?
                const UserDefinedVariablesMap::const_iterator userVarMapIt(userDefinedVariablesMap.find(req.nodeName));
                if (userVarMapIt != userDefinedVariablesMap.end())
                {
                        // yes, us it 
                        const Compiler::VariablesMap& variablesMap(userVarMapIt->second);
                        transform(variablesMap.begin(), variablesMap.end(),
                                          back_inserter(res.variableList), ExtractNameVar());
                }
                else
                {
                        // no, then only show node-defined variables
                        const unsigned nodeId(nodeIt->second);
                        const NodesDescriptionsMap::const_iterator descIt(nodesDescriptions.find(nodeId));
                        const NodeDescription& description(descIt->second);
                        transform(description.namedVariables.begin(), description.namedVariables.end(),
                                          back_inserter(res.variableList), ExtractNameDesc());
                }
                return true;
        }
        else
        {
                ROS_ERROR_STREAM("node " << req.nodeName << " does not exists");
                return false;
        }
}



bool AsebaROS::setVariable(SetVariable::Request& req, SetVariable::Response& res)
{
        // lock the access to the member methods
        unsigned nodeId, pos;
        
        mutex.lock();
        bool exists = getNodePosFromNames(req.nodeName, req.variableName, nodeId, pos);
        mutex.unlock();
        
        if (!exists)
                return false;
        
        SetVariables msg(nodeId, pos, req.data);
        hub.sendMessage(&msg, true);
        return true;
}

bool AsebaROS::getVariable(GetVariable::Request& req, GetVariable::Response& res)
{
        unsigned nodeId, pos;
        
        // lock the access to the member methods, wait will unlock the underlying mutex
        unique_lock<boost::mutex> lock(mutex);
        
        // get information about variable
        bool exists = getNodePosFromNames(req.nodeName, req.variableName, nodeId, pos);
        if (!exists)
                return false;
        bool ok;
        unsigned length = getVariableSize(nodeId, widen(req.variableName), &ok);
        if (!ok)
                return false;
        
        // create query
        const GetVariableQueryKey key(nodeId, pos);
        GetVariableQueryValue query;
        getVariableQueries[key] = &query;
        lock.unlock();
        
        // send message, outside lock to avoid deadlocks
        GetVariables msg(nodeId, pos, length);
        hub.sendMessage(&msg, true);
        system_time const timeout(get_system_time()+posix_time::milliseconds(100));
        
        // wait 100 ms, considering the possibility of spurious wakes
        bool result;
        lock.lock();
        while (query.data.empty())
        {
                result = query.cond.timed_wait(lock, timeout);
                if (!result)
                        break;
        }
        
        // remove key and return answer
        getVariableQueries.erase(key);
        if (result)
        {
                res.data = query.data;
                return true;
        }
        else
        {
                ROS_ERROR_STREAM("read of node " << req.nodeName << ", variable " << req.variableName << " did not return a valid answer within 100ms");
                return false;
        }
}

bool AsebaROS::getEventId(GetEventId::Request& req, GetEventId::Response& res)
{
        // needs locking, called by ROS's service thread
        lock_guard<boost::mutex> lock(mutex);
        size_t id;
        if (commonDefinitions.events.contains(widen(req.name), &id))
        {
                res.id = id;
                return true;
        }
        return false;
}

bool AsebaROS::getEventName(GetEventName::Request& req, GetEventName::Response& res)
{
        // needs locking, called by ROS's service thread
        lock_guard<boost::mutex> lock(mutex);
        if (req.id < commonDefinitions.events.size())
        {
                res.name = narrow(commonDefinitions.events[req.id].name);
                return true;
        }
        return false;
}

bool AsebaROS::getNodePosFromNames(const string& nodeName, const string& variableName, unsigned& nodeId, unsigned& pos) const
{
        // does not need locking, called by other member function already within the lock
        
        // make sure the node exists
        NodesNamesMap::const_iterator nodeIt(nodesNames.find(nodeName));
        if (nodeIt == nodesNames.end())
        {
                ROS_ERROR_STREAM("node " << nodeName << " does not exists");
                return false;
        }
        nodeId = nodeIt->second;
        pos = unsigned(-1);
        
        // check whether variable is user-defined
        const UserDefinedVariablesMap::const_iterator userVarMapIt(userDefinedVariablesMap.find(nodeName));
        if (userVarMapIt != userDefinedVariablesMap.end())
        {
                const Compiler::VariablesMap& userVarMap(userVarMapIt->second);
                const Compiler::VariablesMap::const_iterator userVarIt(userVarMap.find(widen(variableName)));
                if (userVarIt != userVarMap.end())
                {
                        pos = userVarIt->second.first;
                }
        }
        
        // if variable is not user-defined, check whether it is provided by this node
        if (pos == unsigned(-1))
        {
                bool ok;
                pos = getVariablePos(nodeId, widen(variableName), &ok);
                if (!ok)
                {
                        ROS_ERROR_STREAM("variable " << variableName << " does not exists in node " << nodeName);
                        return false;
                }
        }
        return true;
}

void AsebaROS::sendEventOnROS(const UserMessage* asebaMessage)
{
        // does not need locking, called by other member function already within lock
        if ((pubs.size() == commonDefinitions.events.size()) && // if different, we are currently loading a new script, publish on anonymous channel
                (asebaMessage->type < commonDefinitions.events.size()))
        {
                // known, send on a named channel
                shared_ptr<AsebaEvent> event(new AsebaEvent);
                event->stamp = ros::Time::now();
                event->source = asebaMessage->source;
                event->data = asebaMessage->data;
                pubs[asebaMessage->type].publish(event);
        }
        else
        {
                // unknown, send on the anonymous channel
                shared_ptr<AsebaAnonymousEvent> event(new AsebaAnonymousEvent);
                event->stamp = ros::Time::now();
                event->source = asebaMessage->source;
                event->type = asebaMessage->type;
                event->data = asebaMessage->data;
                anonPub.publish(event);
        }
}

void AsebaROS::nodeDescriptionReceived(unsigned nodeId)
{
        // does not need locking, called by parent object
        nodesNames[narrow(nodesDescriptions.at(nodeId).name)] = nodeId;
}

void AsebaROS::eventReceived(const AsebaAnonymousEventConstPtr& event)
{
        // does not need locking, does not touch object's members
        if (event->source == 0)
        {
                // forward only messages with source 0, which means, originating from this computer
                UserMessage userMessage(event->type, event->data);
                hub.sendMessage(&userMessage, true);
        }
}

void AsebaROS::knownEventReceived(const uint16 id, const AsebaEventConstPtr& event)
{
        // does not need locking, does not touch object's members
        if (event->source == 0)
        {
                // forward only messages with source 0, which means, originating from this computer
                UserMessage userMessage(id, event->data);
                hub.sendMessage(&userMessage, true);
        }
}

AsebaROS::AsebaROS(unsigned port, bool forward):
        n("aseba"),
        anonPub(n.advertise<AsebaAnonymousEvent>("anonymous_events", 100)),
        anonSub(n.subscribe("anonymous_events", 100, &AsebaROS::eventReceived, this)),
        hub(this, port, forward) // hub for dashel 
{
        // does not need locking, called by main
        
        // script
        s.push_back(n.advertiseService("load_script", &AsebaROS::loadScript, this));
        
        // nodes
        s.push_back(n.advertiseService("get_node_list", &AsebaROS::getNodeList, this));
        s.push_back(n.advertiseService("get_node_id", &AsebaROS::getNodeId, this));
        s.push_back(n.advertiseService("get_node_name", &AsebaROS::getNodeName, this));
        
        // variables
        s.push_back(n.advertiseService("get_variable_list", &AsebaROS::getVariableList, this));
        s.push_back(n.advertiseService("set_variable", &AsebaROS::setVariable, this));
        s.push_back(n.advertiseService("get_variable", &AsebaROS::getVariable, this));
        
        // events
        s.push_back(n.advertiseService("get_event_id", &AsebaROS::getEventId, this));
        s.push_back(n.advertiseService("get_event_name", &AsebaROS::getEventName, this));
}

AsebaROS::~AsebaROS()
{
        // does not need locking, called by main
        xmlCleanupParser();
}

void AsebaROS::run()
{
        // does not need locking, called by main
        hub.startThread();
        ros::spin();
        //cerr << "ros returned" << endl;
        hub.stopThread();
}

void AsebaROS::processAsebaMessage(Message *message)
{
        // needs locking, called by Dashel hub
        lock_guard<boost::mutex> lock(mutex);
        
        // scan this message for nodes descriptions
        DescriptionsManager::processMessage(message);
        
        // if user message, send to D-Bus as well
        UserMessage *userMessage = dynamic_cast<UserMessage *>(message);
        if (userMessage)
                sendEventOnROS(userMessage);
        
        // if variables, check for pending answers
        Variables *variables = dynamic_cast<Variables *>(message);
        if (variables)
        {
                const GetVariableQueryKey queryKey(variables->source, variables->start);
                GetVariableQueryMap::const_iterator queryIt(getVariableQueries.find(queryKey));
                if (queryIt != getVariableQueries.end())
                {
                        queryIt->second->data = variables->variables;
                        queryIt->second->cond.notify_one();
                }
                else
                        ROS_WARN_STREAM("received Variables from node " << variables->source << ", pos " << variables->start << ", but no corresponding query was found");
        }
}

void dumpHelp(std::ostream &stream, const char *programName)
{
        stream << "AsebaROS, connects aseba components together and with ROS, usage:\n";
        stream << programName << " [options] [additional targets]*\n";
        stream << "Options:\n";
        stream << "-l, --loop      : makes the switch transmit messages back to the send, not only forward them.\n";
        stream << "-p port         : listens to incoming connection on this port\n";
        stream << "-h, --help      : shows this help\n";
        stream << "ROS_OPTIONS     : see ROS documentation\n";
        stream << "Additional targets are any valid Dashel targets." << std::endl;
}

int main(int argc, char *argv[])
{
        ros::init(argc, argv, "aseba");
        
        unsigned port = ASEBA_DEFAULT_PORT;
        bool forward = true;
        std::vector<std::string> additionalTargets;
        
        int argCounter = 1;
        
        while (argCounter < argc)
        {
                const char *arg = argv[argCounter];
                
                if ((strcmp(arg, "-l") == 0) || (strcmp(arg, "--loop") == 0))
                {
                        forward = false;
                }
                else if (strcmp(arg, "-p") == 0)
                {
                        arg = argv[++argCounter];
                        port = atoi(arg);
                }
                else if ((strcmp(arg, "-h") == 0) || (strcmp(arg, "--help") == 0))
                {
                        dumpHelp(std::cout, argv[0]);
                        return 0;
                }
                else
                {
                        additionalTargets.push_back(argv[argCounter]);
                }
                argCounter++;
        }
        
        AsebaROS asebaROS(port, forward);
        
        try
        {
                for (size_t i = 0; i < additionalTargets.size(); i++)
                        asebaROS.connectTarget(additionalTargets[i]);
        }
        catch(Dashel::DashelException e)
        {
                std::cerr << e.what() << std::endl;
        }
        
        asebaROS.run();

        return 0;
}

---

asebaros
Author(s): Stéphane Magnenat
autogenerated on Sat Mar 2 12:32:03 2013