server.cpp

一套Orbacus4.X下有关Corba的学习例程

#include    <OB/CORBA.h>

#include    <algorithm>
#include    <signal.h>
#include    <string>
#ifdef HAVE_FSTREAM
#   include <fstream>
#else
#   include <fstream.h>
#endif

#if defined(HAVE_STD_IOSTREAM) || defined(HAVE_STD_STL)
using namespace std;
#endif

#include    "icp.h"
#include    "server.h"

//----------------------------------------------------------------

// Helper function to write a stringified reference to a file.

void
write_ref(const char * filename, const char * reference)
{
    ofstream file(filename);
    if (!file) {
        string msg("Error opening ");
        msg += filename;
        throw msg.c_str();
    }
    file << reference << endl;
    if (!file) {
        string msg("Error writing ");
        msg += filename;
        throw msg.c_str();
    }
    file.close();
    if (!file) {
        string msg("Error closing ");
        msg += filename;
        throw msg.c_str();
    }
}

//----------------------------------------------------------------

Controller_impl * Thermometer_impl::m_ctrl; // static member

// Helper function to read the model string from a device.

CCS::ModelType
Thermometer_impl::
get_model()
{
    char buf[32];
    if (ICP_get(m_anum, "model", buf, sizeof(buf)) != 0)
        abort();
    return CORBA::string_dup(buf);
}

// Helper function to read the temperature from a device.

CCS::TempType
Thermometer_impl::
get_temp()
{
    short temp;
    if (ICP_get(m_anum, "temperature", &temp, sizeof(temp)) != 0)
        abort();
    return temp;
}

// Helper function to read the location from a device.

CCS::LocType
Thermometer_impl::
get_loc()
{
    char buf[32];
    if (ICP_get(m_anum, "location", buf, sizeof(buf)) != 0)
        abort();
    return CORBA::string_dup(buf);
}

// Helper function to set the location of a device.

void
Thermometer_impl::
set_loc(const char * loc)
{
    if (ICP_set(m_anum, "location", loc) != 0)
        abort();
}

// Constructor.

Thermometer_impl::
Thermometer_impl(
    CCS::AssetType      anum,
    const char *        location
) : m_anum(anum)
{
    if (ICP_online(anum) != 0)      // Mark device as on-line
        abort();
    set_loc(location);              // Set its location
    m_ctrl->add_impl(anum, this);   // Add self to controller's map
}

// Destructor.

Thermometer_impl::
~Thermometer_impl()
{
    try {
        m_ctrl->remove_impl(m_anum); // Remove self from map
        ICP_offline(m_anum);         // Mark device as off-line
    } catch (...) {
        abort();        // Prevent exceptions from escaping
    }
}

// IDL model attribute.

CCS::ModelType
Thermometer_impl::
model() throw(CORBA::SystemException)
{
    return get_model();
}

// IDL asset_num attribute.

CCS::AssetType
Thermometer_impl::
asset_num() throw(CORBA::SystemException)
{
    return m_anum;
}

// IDL temperature attribute.

CCS::TempType
Thermometer_impl::
temperature() throw(CORBA::SystemException)
{
    return get_temp();
}

// IDL location attribute accessor.

CCS::LocType
Thermometer_impl::
location() throw(CORBA::SystemException)
{
    return get_loc();
}

// IDL location attribute modifier.

void
Thermometer_impl::
location(const char * loc) throw(CORBA::SystemException)
{
    set_loc(loc);
}

//----------------------------------------------------------------

// Helper function to get a thermostat's nominal temperature.

CCS::TempType
Thermostat_impl::
get_nominal_temp()
{
    short temp;
    if (ICP_get(m_anum, "nominal_temp", &temp, sizeof(temp)) != 0)
        abort();
    return temp;
}

// Helper function to set a thermostat's nominal temperature.

CCS::TempType
Thermostat_impl::
set_nominal_temp(CCS::TempType new_temp)
throw(CCS::Thermostat::BadTemp)
{
    short old_temp;

    // We need to return the previous nominal temperature,
    // so we first read the current nominal temperature before
    // changing it.
    if (ICP_get(
        m_anum, "nominal_temp", &old_temp, sizeof(old_temp)
       ) != 0) {
        abort();
    }

    // Now set the nominal temperature to the new value.
    if (ICP_set(m_anum, "nominal_temp", &new_temp) != 0) {

        // If ICP_set() failed, read this thermostat's minimum
        // and maximum so we can initialize the BadTemp exception.
        CCS::Thermostat::BtData btd;
        ICP_get(
            m_anum, "MIN_TEMP",
            &btd.min_permitted, sizeof(btd.min_permitted)
        );
        ICP_get(
            m_anum, "MAX_TEMP",
            &btd.max_permitted, sizeof(btd.max_permitted)
        );
        btd.requested = new_temp;
        btd.error_msg = CORBA::string_dup(
            new_temp > btd.max_permitted ? "Too hot" : "Too cold"
        );
        throw CCS::Thermostat::BadTemp(btd);
    }
    return old_temp;
}

// Constructor.

Thermostat_impl::
Thermostat_impl(
    CCS::AssetType      anum,
    const char *        location,
    CCS::TempType       nominal_temp
) : Thermometer_impl(anum, location)
{
    // Base Thermometer_impl constructor does most of the
    // work, so we need only set the nominal temperature here.
    set_nominal_temp(nominal_temp);
}

// IDL get_nominal operation.

CCS::TempType
Thermostat_impl::
get_nominal() throw(CORBA::SystemException)
{
    return get_nominal_temp();
}

// IDL set_nominal operation.

CCS::TempType
Thermostat_impl::
set_nominal(CCS::TempType new_temp)
throw(CORBA::SystemException, CCS::Thermostat::BadTemp)
{
    return set_nominal_temp(new_temp);
}

//----------------------------------------------------------------

// Helper function for thermometers and thermostats to
// add themselves to the m_assets map.

void
Controller_impl::
add_impl(CCS::AssetType anum, Thermometer_impl * tip)
{
    m_assets[anum] = tip;
}

// Helper function for thermometers and thermostats to
// remove themselves from the m_assets map.

void
Controller_impl::
remove_impl(CCS::AssetType anum)
{
    m_assets.erase(anum);
}

// IDL list operation.

CCS::Controller::ThermometerSeq *
Controller_impl::
list() throw(CORBA::SystemException)
{
    // Create a new thermometer sequence. Because we know
    // the number of elements we will put onto the sequence,
    // we use the maximum constructor.
    CCS::Controller::ThermometerSeq_var listv
        = new CCS::Controller::ThermometerSeq(m_assets.size());
    listv->length(m_assets.size());

    // Loop over the m_assets map and create a
    // reference for each device.
    CORBA::ULong count = 0;
    AssetMap::iterator i;
    for (i = m_assets.begin(); i != m_assets.end(); ++i)
        listv[count++] = i->second->_this();
    return listv._retn();
}

// IDL change operation.

void
Controller_impl::
change(
    const CCS::Controller::ThermostatSeq &  tlist,
    CORBA::Short                            delta
) throw(CORBA::SystemException, CCS::Controller::EChange)
{
    CCS::Controller::EChange ec;    // Just in case we need it

    // We cannot add a delta value to a thermostat's temperature
    // directly, so for each thermostat, we read the nominal
    // temperature, add the delta value to it, and write
    // it back again.
    CORBA::ULong i;
    for (i = 0; i < tlist.length(); ++i) {
        if (CORBA::is_nil(tlist[i]))
            continue;                       // Skip nil references

        // Read nominal temp and update it.
        CCS::TempType tnom = tlist[i]->get_nominal();
        tnom += delta;
        try {
            tlist[i]->set_nominal(tnom);
        }
        catch (const CCS::Thermostat::BadTemp & bt) {
            // If the update failed because the temperature
            // is out of range, we add the thermostat's info
            // to the errors sequence.
            CORBA::ULong len = ec.errors.length();
            ec.errors.length(len + 1);
            ec.errors[len].tmstat_ref = tlist[i];
            ec.errors[len].info = bt.details;
        }
    }

    // If we encountered errors in the above loop,
    // we will have added elements to the errors sequence.
    if (ec.errors.length() != 0)
        throw ec;
}

// IDL find operation

void
Controller_impl::
find(CCS::Controller::SearchSeq & slist)
throw(CORBA::SystemException)
{
    // Loop over input list and look up each device.
    CORBA::ULong listlen = slist.length();
    CORBA::ULong i;
    for (i = 0; i < listlen; ++i) {

        AssetMap::iterator where;   // Iterator for asset map
        int num_found = 0;          // Num matched per iteration

        // Assume we will not find a matching device.
        slist[i].device = CCS::Thermometer::_nil();

        // Work out whether we are searching by asset,
        // model, or location.
        CCS::Controller::SearchCriterion sc = slist[i].key._d();
        if (sc == CCS::Controller::ASSET) {
            // Search for matching asset number.
            where = m_assets.find(slist[i].key.asset_num());
            if (where != m_assets.end())
                slist[i].device = where->second->_this();
        } else {
            // Search for model or location string.
            const char * search_str;
            if (sc == CCS::Controller::LOCATION)
                search_str = slist[i].key.loc();
            else
                search_str = slist[i].key.model_desc();

            // Find first matching device (if any).
            where = find_if(
                        m_assets.begin(), m_assets.end(),
                        StrFinder(sc, search_str)
                    );

            // While there are matches...
            while (where != m_assets.end()) {
                if (num_found == 0) {
                    // First match overwrites reference
                    // in search record.
                    slist[i].device = where->second->_this();
                } else {
                    // Each further match appends a new
                    // element to the search sequence.
                    CORBA::ULong len = slist.length();
                    slist.length(len + 1);
                    slist[len].key = slist[i].key;
                    slist[len].device = where->second->_this();
                }
                ++num_found;

                // Find next matching device with this key.
                where = find_if(
                            ++where, m_assets.end(),
                            StrFinder(sc, search_str)
                        );
            }
        }
    }
}

//----------------------------------------------------------------

void
run(CORBA::ORB_ptr orb)
{
    // Get reference to Root POA.
    CORBA::Object_var obj = orb->resolve_initial_references("RootPOA");
    PortableServer::POA_var poa = PortableServer::POA::_narrow(obj);

    // Create a controller and set static m_ctrl member
    // for thermostats and thermometers.
    Controller_impl ctrl_servant;
    Thermometer_impl::m_ctrl = &ctrl_servant;

    // Write controller stringified reference to ctrl.ref.
    CCS::Controller_var ctrl = ctrl_servant._this();
    CORBA::String_var str = orb->object_to_string(ctrl);
    write_ref("ctrl.ref", str);

    // Create a few devices. (Thermometers have odd asset
    // numbers, thermostats have even asset numbers.)
    Thermometer_impl thermo1(2029, "Deep Thought");
    Thermometer_impl thermo2(8053, "HAL");
    Thermometer_impl thermo3(1027, "ENIAC");

    Thermostat_impl tmstat1(3032, "Colossus", 68);
    Thermostat_impl tmstat2(4026, "ENIAC", 60);
    Thermostat_impl tmstat3(4088, "ENIAC", 50);
    Thermostat_impl tmstat4(8042, "HAL", 40);

    // Write a thermostat reference to tmstat.ref.
    CCS::Thermostat_var tmstat = tmstat1._this();
    str = orb->object_to_string(tmstat);
    write_ref("tmstat.ref", str);

    // Activate POA manager
    PortableServer::POAManager_var mgr = poa->the_POAManager();
    mgr->activate();

    // Accept requests
    orb->run();
}

//----------------------------------------------------------------

static CORBA::ORB_var orb; // Global, so handler can see it.

//----------------------------------------------------------------

#ifdef WIN32
BOOL
handler(DWORD)
{
    // Inform JTC of presence of new thread
    JTCAdoptCurrentThread adopt;

    // Terminate event loop
    try {
        if (!CORBA::is_nil(orb))
            orb->shutdown(false);
    } catch (...) {
        // Can't throw here...
    }
    return TRUE;
}
#else
extern "C"
void
handler(int)
{
     // Ignore further signals
    struct sigaction ignore;
    ignore.sa_handler = SIG_IGN;
    sigemptyset(&ignore.sa_mask);
    ignore.sa_flags = 0;
    if (sigaction(SIGINT, &ignore, (struct sigaction *)0) == -1)
        abort();
    if (sigaction(SIGTERM, &ignore, (struct sigaction *)0) == -1)
        abort();
    if (sigaction(SIGHUP, &ignore, (struct sigaction *)0) == -1)
        abort();

    // Terminate event loop
    try {
        if (!CORBA::is_nil(orb))
            orb->shutdown(false);
    } catch (...) {
        // Can't throw here...
    }
}
#endif

//----------------------------------------------------------------

int
main(int argc, char* argv[])
{
    // Install signal handler for cleanup
#ifdef WIN32
    BOOL rc = SetConsoleCtrlHandler((PHANDLER_ROUTINE)handler, TRUE);
    if (!rc)
        abort();
#else
    struct sigaction sa;            // New signal state
    sa.sa_handler = handler;        // Set handler function
    sigfillset(&sa.sa_mask);        // Mask all other signals
                                    // while handler runs
    sa.sa_flags = 0 | SA_RESTART;   // Restart interrupted syscalls

    if (sigaction(SIGINT, &sa, (struct sigaction *)0) == -1)
        abort();
    if (sigaction(SIGHUP, &sa, (struct sigaction *)0) == -1)
        abort();
    if (sigaction(SIGTERM, &sa, (struct sigaction *)0) == -1)
        abort();
#endif

    // Initialize the ORB and start working...
    int status = 0;
    try {
        orb = CORBA::ORB_init(argc, argv);
        run(orb);
    } catch (const CORBA::Exception & ex) {
        cerr << "Uncaught CORBA exception: " << ex << endl;
        status = 1;
    } catch (...) {
        cerr << "Uncaught non-CORBA exception" << endl;
        status = 1;
    }

    // Destroy the ORB.
    if (!CORBA::is_nil(orb)) {
        try {
            orb->destroy();
        } catch (const CORBA::Exception & ex) {
            cerr << "Cannot destroy ORB: " << ex << endl;
            status = 1;
        }
    }

    return status;
}