XML-RPC for C/C++ (Xmlrpc-c) Code

/* A simple standalone RPC server based on an Xmlrpc-c packet socket.

   This program expects the invoker to provide an established connection
   to a client as Standard Input (E.g. Inetd can do this).  It processes
   RPCs from that connection until the client closes the connection.

   This is not an XML-RPC server, because it uses a simple packet socket
   instead of HTTP.  See xmlrpc_sample_add_server.cpp for an example of
   an XML-RPC server.

   The advantage of this example over XML-RPC is that it has a connection
   concept.  The client can be connected indefinitely and the server gets
   notified when the client terminates, even if it gets aborted by its OS.
*/

#ifndef WIN32
#include <unistd.h>
#endif
#include <cassert>
#include <iostream>
#include <sys/signal.h>

#include <xmlrpc-c/base.hpp>
#include <xmlrpc-c/registry.hpp>
#include <xmlrpc-c/server_pstream.hpp>

using namespace std;


class sampleAddMethod : public xmlrpc_c::method {
public:
    sampleAddMethod() {
        // signature and help strings are documentation -- the client
        // can query this information with a system.methodSignature and
        // system.methodHelp RPC.
        this->_signature = "i:ii";  // method's arguments are two integers
        this->_help = "This method adds two integers together";
    }
    void
    execute(xmlrpc_c::paramList const& paramList,
            xmlrpc_c::value *   const  retvalP) {
        
        int const addend(paramList.getInt(0));
        int const adder(paramList.getInt(1));
        
        paramList.verifyEnd(2);
        
        *retvalP = xmlrpc_c::value_int(addend + adder);
    }
};



int 
main(int           const, 
     const char ** const) {

    // It's a good idea to disable SIGPIPE signals; if client closes his end
    // of the pipe/socket, we'd rather see a failure to send a response than
    // get killed by the OS.
    signal(SIGPIPE, SIG_IGN);

    try {
        xmlrpc_c::registry myRegistry;

        xmlrpc_c::methodPtr const sampleAddMethodP(new sampleAddMethod);

        myRegistry.addMethod("sample.add", sampleAddMethodP);

        xmlrpc_c::serverPstreamConn server(
            xmlrpc_c::serverPstreamConn::constrOpt()
            .socketFd(STDIN_FILENO)
            .registryP(&myRegistry));

        for (bool clientHasDisconnected = false; !clientHasDisconnected;)
            server.runOnce(&clientHasDisconnected);
                // This reads one packet (containing an XML-RPC call message)
                // from Standard Input, executes the indicated RPC, and writes
                // one packet containing the XML-RPC response message to
                // Standard Input.

    } catch (exception const& e) {
        cerr << "Something threw an error: " << e.what() << endl;
    }
    return 0;
}