CAmDbusWrapper.cpp

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#include "CAmDbusWrapper.h"
#include <audiomanagerconfig.h>
#include <fstream>
#include <sstream>
#include <string>
#include <cassert>
#include <cstdlib>
#include <stdexcept>
#include "CAmDltWrapper.h"
#include "CAmSocketHandler.h"

namespace am
{

#define ROOT_INTROSPECT_XML                                             \
DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE                               \
"<node>"                                                                \
"<interface name='org.AudioManager.freedesktop.DBus.Introspectable'>"   \
"<method name='Introspect'>"                                            \
"   <arg name='xml_data' type='s' direction='out'/>"                    \
"</method>"                                                             \
"</interface>"                                                          \

CAmDbusWrapper* CAmDbusWrapper::mpReference = NULL;

CAmDbusWrapper::CAmDbusWrapper(CAmSocketHandler* socketHandler, DBusBusType type, const std::string& prefix, const std::string& objectPath) :
        pDbusPrepareCallback(this,&CAmDbusWrapper::dbusPrepareCallback), //
        pDbusDispatchCallback(this, &CAmDbusWrapper::dbusDispatchCallback), //
        pDbusFireCallback(this, &CAmDbusWrapper::dbusFireCallback), //
        pDbusCheckCallback(this, &CAmDbusWrapper::dbusCheckCallback), //
        pDbusTimerCallback(this, &CAmDbusWrapper::dbusTimerCallback), //
        mpDbusConnection(0), //
        mDBusError(), //
        mListNodes(), //
        mpListTimerhandles(), //
        mpSocketHandler(socketHandler), //
        mDbusType(type)
{
    assert(mpSocketHandler!=0);

    dbus_error_init(&mDBusError);

    if (!dbus_threads_init_default())
        logError("CAmDbusWrapper::CAmDbusWrapper threads init call failed");

    logInfo("DBusWrapper::DBusWrapper Opening DBus connection of:", prefix, objectPath);
    mpDbusConnection = dbus_bus_get(mDbusType, &mDBusError);
    if (dbus_error_is_set(&mDBusError))
    {
        logError("DBusWrapper::DBusWrapper Error while getting the DBus");
        dbus_error_free(&mDBusError);
    }
    if (NULL == mpDbusConnection)
    {
        logError("DBusWrapper::DBusWrapper DBus Connection is null");
    }
    else
    {
        logInfo("DBusWrapper::DBusWrapper DBus Connection is", mpDbusConnection);
    }

    //then we need to adopt the dbus to our mainloop:
    //first, we are old enought to live longer then the connection:
    dbus_connection_set_exit_on_disconnect(mpDbusConnection, FALSE);

    //we do not need the manual dispatching, since it is not allowed to call from a different thread. So leave it uncommented:
    //dbus_connection_set_dispatch_status_function

    //add watch functions:
    dbus_bool_t watch = dbus_connection_set_watch_functions(mpDbusConnection, addWatch, removeWatch, toogleWatch, this, NULL);
    if (!watch)
    {
        logError("DBusWrapper::DBusWrapper Registering of watch functions failed");
    }

    //add timer functions:
    dbus_bool_t timer = dbus_connection_set_timeout_functions(mpDbusConnection, addTimeout, removeTimeout, toggleTimeout, this, NULL);
    if (!timer)
    {
        logError("DBusWrapper::DBusWrapper Registering of timer functions failed");
    }

    if (prefix.empty() && objectPath.empty())
    {
        logInfo("DBusWrapper::DBusWrapper We don't register a connection object!");
        return;
    }

    //register callback for Introspectio
    mObjectPathVTable.message_function = CAmDbusWrapper::cbRootIntrospection;
    dbus_connection_register_object_path(mpDbusConnection, objectPath.c_str(), &mObjectPathVTable, this);
    int ret = dbus_bus_request_name(mpDbusConnection, prefix.c_str(), DBUS_NAME_FLAG_DO_NOT_QUEUE, &mDBusError);
    if (DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER == ret)
    {
        logInfo("DBusWrapper::DBusWrapper We own", prefix);
    }
    else
    {
        std::ostringstream sserror("DBusWrapper::DBusWrapper ");
        switch (ret)
        {
            case -1:
                sserror << "Couldn't acquire name " << prefix << ". DBus message: " << mDBusError.message;
                dbus_error_free(&mDBusError);
                break;
            case DBUS_REQUEST_NAME_REPLY_IN_QUEUE:
                sserror << "We are queued for " << prefix;
                break;
            case DBUS_REQUEST_NAME_REPLY_EXISTS:
                sserror << ":-( " << prefix << " already exists!";
                break;
            case DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER:
                sserror << "Eh? We already own " << prefix;
                break;
            default:
                sserror << "Unknown result = " << ret;
                break;
        }

        logError(sserror.str());
        throw std::runtime_error(sserror.str().c_str());
    }
}

CAmDbusWrapper::~CAmDbusWrapper()
{
    //close the connection again
    logInfo("DBusWrapper::~DBusWrapper Closing DBus connection");
    dbus_connection_unref(mpDbusConnection);

    //clean up all timerhandles we created but did not delete before
    std::vector<sh_timerHandle_t*>::iterator it = mpListTimerhandles.begin();
    for (; it != mpListTimerhandles.end(); ++it)
    {
        delete *it;
    }
}

void CAmDbusWrapper::registerCallback(const DBusObjectPathVTable* vtable, const std::string& path, void* userdata, const std::string& prefix)
{
    logInfo("DBusWrapper::registerCallback register callback:", path);

    std::string completePath = prefix + "/" + path;
    dbus_error_init(&mDBusError);
    dbus_connection_register_object_path(mpDbusConnection, completePath.c_str(), vtable, userdata);
    if (dbus_error_is_set(&mDBusError))
    {
        logError("DBusWrapper::registerCallack error: ", mDBusError.message);
        dbus_error_free(&mDBusError);
    }
    mListNodes.push_back(path);
}

void CAmDbusWrapper::registerSignalWatch(DBusHandleMessageFunction handler, const std::string& rule, void* userdata)
{
    logInfo("DBusWrapper::registerSignalWatch register callback:", rule);
    dbus_error_init(&mDBusError);
    dbus_bus_add_match(mpDbusConnection, rule.c_str(), &mDBusError);
    dbus_connection_flush(mpDbusConnection);
    dbus_connection_add_filter(mpDbusConnection, handler, userdata, 0);

    if (dbus_error_is_set(&mDBusError))
    {
        logError("DBusWrapper::registerCallack error: ", mDBusError.message);
        dbus_error_free(&mDBusError);
    }
}
DBusHandlerResult CAmDbusWrapper::cbRootIntrospection(DBusConnection *conn, DBusMessage *msg, void *reference)
{
    //logInfo("DBusWrapper::~cbRootIntrospection called:");

    mpReference = (CAmDbusWrapper*) reference;
    std::vector<std::string> nodesList = mpReference->mListNodes;
    DBusMessage * reply;
    DBusMessageIter args;
    dbus_uint32_t serial = 0;
    if (dbus_message_is_method_call(msg, DBUS_INTERFACE_INTROSPECTABLE, "Introspect"))
    {
        std::vector<std::string>::iterator nodeIter = nodesList.begin();
        const char *xml = ROOT_INTROSPECT_XML;
        std::stringstream introspect;
        introspect << std::string(xml);
        for (; nodeIter != nodesList.end(); ++nodeIter)
        {
            introspect << "<node name='" << nodeIter->c_str() << "'/>";
        }
        introspect << "</node>";

        reply = dbus_message_new_method_return(msg);
        std::string s = introspect.str();
        const char* string = s.c_str();

        // add the arguments to the reply
        dbus_message_iter_init_append(reply, &args);
        if (!dbus_message_iter_append_basic(&args, DBUS_TYPE_STRING, &string))
        {
            logError("DBusWrapper::~cbRootIntrospection DBUS Out Of Memory!");
        }

        // send the reply && flush the connection
        if (!dbus_connection_send(conn, reply, &serial))
        {
            logError("DBusWrapper::~cbRootIntrospection DBUS Out Of Memory!");
        }
        dbus_connection_flush(conn);
        // free the reply
        dbus_message_unref(reply);

        return (DBUS_HANDLER_RESULT_HANDLED);
    }
    else
    {
        return (DBUS_HANDLER_RESULT_NOT_YET_HANDLED);
    }
}

void CAmDbusWrapper::getDBusConnection(DBusConnection *& connection) const
{
    connection = mpDbusConnection;
}

dbus_bool_t CAmDbusWrapper::addWatch(DBusWatch *watch, void *userData)
{
    mpReference = (CAmDbusWrapper*) userData;
    assert(mpReference!=0);
    return (mpReference->addWatchDelegate(watch, userData));
}

dbus_bool_t CAmDbusWrapper::addWatchDelegate(DBusWatch * watch, void* userData)
{
    (void) userData;
    int16_t event = 0;
    sh_pollHandle_t handle = 0;
    uint flags = dbus_watch_get_flags(watch);

    /* no watch flags for disabled watches */
    if (dbus_watch_get_enabled(watch))
    {
        if (flags & DBUS_WATCH_READABLE)
            event |= POLLIN;
        if (flags & DBUS_WATCH_WRITABLE)
            event |= POLLOUT;

        logInfo("DBusWrapper::addWatchDelegate entered new watch, fd=", dbus_watch_get_unix_fd(watch), "event flag=", event);
        am_Error_e error = mpSocketHandler->addFDPoll(dbus_watch_get_unix_fd(watch), event, &pDbusPrepareCallback, &pDbusFireCallback, &pDbusCheckCallback, &pDbusDispatchCallback, watch, handle);

        //if everything is alright, add the watch and the handle to our map so we know this relationship
        if (error == E_OK && handle != 0)
        {
            mMapHandleWatch.insert(std::make_pair(watch, handle));
            return (true);
        }
        logError("DBusWrapper::addWatchDelegate entering watch failed");
    }
    return (true);
}

void CAmDbusWrapper::removeWatch(DBusWatch *watch, void *userData)
{
    mpReference = (CAmDbusWrapper*) userData;
    assert(mpReference!=0);
    mpReference->removeWatchDelegate(watch, userData);
}

void CAmDbusWrapper::removeWatchDelegate(DBusWatch *watch, void *userData)
{
    (void) userData;
    std::map<DBusWatch*, sh_pollHandle_t>::iterator iterator = mMapHandleWatch.begin();
    iterator = mMapHandleWatch.find(watch);
    if (iterator != mMapHandleWatch.end())
    {
        mpSocketHandler->removeFDPoll(iterator->second);
        logInfo("DBusWrapper::removeWatch removed watch with handle", iterator->second);
        mMapHandleWatch.erase(iterator);
    }
    else
    {
        logError("DBusWrapper::removeWatch could not find handle !");
    }
}

void CAmDbusWrapper::toogleWatch(DBusWatch *watch, void *userData)
{
    mpReference = (CAmDbusWrapper*) userData;
    assert(mpReference!=0);
    mpReference->toogleWatchDelegate(watch, userData);
}

void CAmDbusWrapper::toogleWatchDelegate(DBusWatch *watch, void *userData)
{
    (void) userData;
    int16_t event = 0;
    dbus_watch_get_unix_fd(watch);
    uint flags = dbus_watch_get_flags(watch);
    /* no watch flags for disabled watches */
    if (dbus_watch_get_enabled(watch))
    {
        if (flags & DBUS_WATCH_READABLE)
            event |= POLLIN;
        if (flags & DBUS_WATCH_WRITABLE)
            event |= POLLOUT;
    }
    std::map<DBusWatch*, sh_pollHandle_t>::iterator iterator = mMapHandleWatch.begin();
    iterator = mMapHandleWatch.find(watch);
    if (iterator != mMapHandleWatch.end())
        mpSocketHandler->updateEventFlags(iterator->second, event);
}

dbus_bool_t CAmDbusWrapper::addTimeout(DBusTimeout *timeout, void* userData)
{
    mpReference = (CAmDbusWrapper*) userData;
    assert(mpReference!=0);
    return (mpReference->addTimeoutDelegate(timeout, userData));
}

dbus_bool_t CAmDbusWrapper::addTimeoutDelegate(DBusTimeout *timeout, void* userData)
{
    (void)userData;

    if (!dbus_timeout_get_enabled(timeout))
        return (false);

    //calculate the timeout in timeval
    timespec pollTimeout;
    int localTimeout = dbus_timeout_get_interval(timeout);
    pollTimeout.tv_sec = localTimeout / 1000;
    pollTimeout.tv_nsec = (localTimeout % 1000) * 1000000;

    //prepare handle and callback. new is eval, but there is no other choice because we need the pointer!
    sh_timerHandle_t* handle = new sh_timerHandle_t;
    mpListTimerhandles.push_back(handle);

    //add the timer to the pollLoop
    mpSocketHandler->addTimer(pollTimeout, &pDbusTimerCallback, *handle, timeout);

    //save the handle with dbus context
    dbus_timeout_set_data(timeout, handle, NULL);

    return (true);
}

void CAmDbusWrapper::removeTimeout(DBusTimeout *timeout, void* userData)
{
    mpReference = (CAmDbusWrapper*) userData;
    assert(mpReference!=0);
    mpReference->removeTimeoutDelegate(timeout, userData);
}

void CAmDbusWrapper::removeTimeoutDelegate(DBusTimeout *timeout, void* userData)
{
    (void) userData;
    //get the pointer to the handle and remove the timer
    sh_timerHandle_t* handle = (sh_timerHandle_t*) dbus_timeout_get_data(timeout);
    mpSocketHandler->removeTimer(*handle);

    //now go throught the timerlist and remove the pointer, free memory
    std::vector<sh_timerHandle_t*>::iterator it = mpListTimerhandles.begin();
    for (; it != mpListTimerhandles.end(); ++it)
    {
        if (*it == handle)
        {
            mpListTimerhandles.erase(it);
            break;
        }
    }
    delete handle;
 }

void CAmDbusWrapper::toggleTimeout(DBusTimeout *timeout, void* userData)
{
    mpReference = (CAmDbusWrapper*) userData;
    assert(mpReference!=0);
    mpReference->toggleTimeoutDelegate(timeout, userData);
}

bool am::CAmDbusWrapper::dbusDispatchCallback(const sh_pollHandle_t handle, void *userData)
{
    (void) handle;
    (void) userData;
    bool returnVal = true;
    dbus_connection_ref(mpDbusConnection);
    if (dbus_connection_dispatch(mpDbusConnection) == DBUS_DISPATCH_COMPLETE)
        returnVal = false;
    dbus_connection_unref(mpDbusConnection);
    //logInfo("DBusWrapper::dbusDispatchCallback was called");
    return (returnVal);
}

bool am::CAmDbusWrapper::dbusCheckCallback(const sh_pollHandle_t handle, void *userData)
{
    (void) handle;
    (void) userData;
    bool returnVal = false;
    dbus_connection_ref(mpDbusConnection);
    if (dbus_connection_get_dispatch_status(mpDbusConnection) == DBUS_DISPATCH_DATA_REMAINS)
        returnVal = true;
    dbus_connection_unref(mpDbusConnection);
    //logInfo("DBusWrapper::dbusCheckCallback was called");
    return (returnVal);
}

void am::CAmDbusWrapper::dbusFireCallback(const pollfd pollfd, const sh_pollHandle_t handle, void *userData)
{
    (void) handle;
    (void) userData;
    assert(userData!=NULL);
    uint flags = 0;

    if (pollfd.revents & POLLIN)
        flags |= DBUS_WATCH_READABLE;
    if (pollfd.revents & POLLOUT)
        flags |= DBUS_WATCH_WRITABLE;
    if (pollfd.revents & POLLHUP)
        flags |= DBUS_WATCH_HANGUP;
    if (pollfd.revents & POLLERR)
        flags |= DBUS_WATCH_ERROR;

    DBusWatch *watch = (DBusWatch*) userData;

    dbus_connection_ref(mpDbusConnection);
    dbus_watch_handle(watch, flags);
    dbus_connection_unref(mpDbusConnection);
    //logInfo("DBusWrapper::dbusFireCallback was called");
}

void CAmDbusWrapper::dbusPrepareCallback(const sh_pollHandle_t handle, void* userData)
{
    (void) handle;
    (void) userData;
    dbus_connection_ref(mpDbusConnection);
    while (dbus_connection_get_dispatch_status(mpDbusConnection) == DBUS_DISPATCH_DATA_REMAINS)
    {
       dbus_connection_dispatch(mpDbusConnection);
       //logInfo("prepare was neccessary!");
    }
    dbus_connection_unref(mpDbusConnection);
}

void CAmDbusWrapper::toggleTimeoutDelegate(DBusTimeout *timeout, void* userData)
{
    (void) userData;
    //get the pointer to the handle and remove the timer
    sh_timerHandle_t* handle = (sh_timerHandle_t*) dbus_timeout_get_data(timeout);

    //stop or restart?
    if (dbus_timeout_get_enabled(timeout))
    {
        //calculate the timeout in timeval
        timespec pollTimeout;
        int localTimeout = dbus_timeout_get_interval(timeout);
        pollTimeout.tv_sec = localTimeout / 1000;
        pollTimeout.tv_nsec = (localTimeout % 1000) * 1000000;
        mpSocketHandler->updateTimer(*handle, pollTimeout);
    }
    else
    {
        mpSocketHandler->stopTimer(*handle);
    }
}

void CAmDbusWrapper::dbusTimerCallback(sh_timerHandle_t handle, void *userData)
{
    assert(userData!=NULL);
    for (auto && timerHandle : mpListTimerhandles)
    {
        if (*timerHandle == handle)
        {
            if (dbus_timeout_get_enabled((DBusTimeout*) userData))
            {
                mpSocketHandler->restartTimer(handle);
            }
            dbus_timeout_handle((DBusTimeout*) userData);
            return;
        }
    }
    logWarning("CAmDbusWrapper::dbusTimerCallback Unknown timer handle");
}
}