namespace libt2n
{
-command_client::command_client(client_connection& _c)
+command_client::command_client(client_connection* _c, long long _command_timeout_usec, long long _hello_timeout_usec)
: c(_c)
{
+ command_timeout_usec=_command_timeout_usec;
+ hello_timeout_usec=_hello_timeout_usec;
+
// for reconnects
- c.add_callback(new_connection,bind(&command_client::read_hello, boost::ref(*this)));
+ c->add_callback(new_connection,bind(&command_client::read_hello, boost::ref(*this)));
+
+ // don't expect hello from an always closed connection (like dummy_client_connection)
+ if (!is_connection_closed())
+ {
+ try
+ {
+ read_hello();
+ }
+ catch (t2n_communication_error &e)
+ {
+ c->close();
+
+ // store a copy of the exception that you can find out details about the error later
+ std::auto_ptr<t2n_exception> tmp(e.clone());
+ constructorException=tmp;
+ }
+ catch (...)
+ {
+ throw;
+ }
+ }
+}
+
+/** @brief replace the connection currently in use with a new one
+ @param _c pointer to the new connection
+
+ @note the old connection must still be valid when this method is called,
+ it can safely be deleted after this method returned
+
+ @note all callbacks registered on the old connection will be copied over
+ to the new one
+*/
+void command_client::replace_connection(client_connection* _c)
+{
+ // copy all callbacks registered on the old connection
+ for(callback_event_type e=static_cast<callback_event_type>(0);
+ e < __events_end;
+ e=static_cast<callback_event_type>(static_cast<int>(e)+1))
+ {
+ list<boost::function<void ()> > evcb=c->get_callback_list(e);
+
+ for (list<boost::function<void ()> >::iterator i=evcb.begin(); i != evcb.end(); i++)
+ _c->add_callback(e,*i);
+ }
+
+ // replace the connection
+ c=_c;
read_hello();
}
+/** @brief return a complete packet
+ @param usec_timeout maximum microseconds to wait until the packet is complete
+ @retval packet data as std::string
+
+ @note throws a t2n_transfer_error if the timeout is exceeded
+*/
+std::string command_client::read_packet(const long long &usec_timeout)
+{
+ string resultpacket;
+ bool got_packet=false;
+ long long my_timeout=usec_timeout;
+ while(!(got_packet=c->get_packet(resultpacket)) && my_timeout > 0 && !c->is_closed())
+ c->fill_buffer(my_timeout,&my_timeout);
+
+ if (!got_packet)
+ throw t2n_transfer_error("timeout exceeded");
+
+ return resultpacket;
+}
+
+/** @brief read and check the hello message at the beginning of a connection
+
+ @note throws exceptions if something went wrong
+*/
void command_client::read_hello()
{
- // TODO: fix timeout
string resultpacket;
- while(!c.get_packet(resultpacket) && !c.is_closed())
- c.fill_buffer();
+ bool got_packet=false;
+ long long my_timeout=hello_timeout_usec;
+ while(!(got_packet=c->get_packet(resultpacket)) && my_timeout > 0 && !c->is_closed())
+ {
+ c->fill_buffer(my_timeout,&my_timeout);
+
+ c->peek_packet(resultpacket);
+ check_hello(resultpacket); // will throw before timeout if wrong data received
+ }
+
+ if (!got_packet)
+ throw t2n_transfer_error("timeout exceeded");
+
+ if (!check_hello(resultpacket))
+ throw t2n_version_mismatch("illegal hello received (incomplete): "+resultpacket);
+}
- istringstream hello(resultpacket);
+/** @brief check if a hello message is valid
+ @param hellostr std::string with the message to check
+ @retval true if the hello is good and complete
- char chk[5];
- hello.read(chk,4);
- chk[4]=0;
- if (hello.fail() || hello.eof() || string("T2Nv") != chk)
- throw t2n_version_mismatch("illegal hello received (T2N)");
+ @note you can check incomplete hellos. you will get a false return value
+ but no exception. throws exceptions as soon as something is wrong.
+*/
+bool command_client::check_hello(const std::string& hellostr)
+{
+ istringstream hello(hellostr);
+
+ char chk;
+
+ if (hello.read(&chk,1))
+ {
+ if (chk != 'T')
+ throw t2n_version_mismatch("illegal hello received (T2N)");
+ }
+ else
+ return false;
+
+ if (hello.read(&chk,1))
+ {
+ if (chk != '2')
+ throw t2n_version_mismatch("illegal hello received (T2N)");
+ }
+ else
+ return false;
+
+ if (hello.read(&chk,1))
+ {
+ if (chk != 'N')
+ throw t2n_version_mismatch("illegal hello received (T2N)");
+ }
+ else
+ return false;
+
+ if (hello.read(&chk,1))
+ {
+ if (chk != 'v')
+ throw t2n_version_mismatch("illegal hello received (T2N)");
+ }
+ else
+ return false;
int prot_version;
- hello >> prot_version;
- if (hello.fail() || hello.eof() || prot_version != PROTOCOL_VERSION)
- throw t2n_version_mismatch("not compatible with the server protocol version");
+ if (hello >> prot_version)
+ {
+ if (prot_version != PROTOCOL_VERSION)
+ throw t2n_version_mismatch("not compatible with the server protocol version");
+ }
+ else
+ return false;
- hello.read(chk,1);
- if (hello.fail() || hello.eof() || chk[0] != ';')
- throw t2n_version_mismatch("illegal hello received (1. ;)");
+ if (hello.read(&chk,1))
+ {
+ if (chk != ';')
+ throw t2n_version_mismatch("illegal hello received (1. ;)");
+ }
+ else
+ return false;
- hello.read(chk,4);
- if (hello.fail() || hello.eof() || *((int*)chk) != 1)
- throw t2n_version_mismatch("host byte order not matching");
+ unsigned int hbo;
+ if (hello.read((char*)&hbo,sizeof(hbo)))
+ {
+ if (hbo != 1)
+ throw t2n_version_mismatch("host byte order not matching");
+ }
+ else
+ return false;
- hello.read(chk,1);
- if (hello.fail() || hello.eof() || chk[0] != ';')
- throw t2n_version_mismatch("illegal hello received (2. ;)");
+ if (hello.read(&chk,1))
+ {
+ if (chk != ';')
+ throw t2n_version_mismatch("illegal hello received (2. ;)");
+ }
+ else
+ return false;
+
+ return true;
}
+/** @brief send a command to the server and store the result
+ @param cmd pointer to a command-object
+ @param[out] res result container to store the result in
+
+ @note you can check incomplete hellos. you will get a false return value
+ but no exception. throws exceptions as soon as something is wrong.
+*/
void command_client::send_command(command* cmd, result_container &res)
{
ostringstream ofs;
command_container cc(cmd);
boost::archive::binary_oarchive oa(ofs);
- // TODO: exceptions
- oa << cc;
+ if (is_connection_closed())
+ throw t2n_transfer_error("connection to server is closed");
+
+ try
+ {
+ oa << cc;
+ }
+ catch(boost::archive::archive_exception &e)
+ {
+ ostringstream msg;
+ msg << "archive_exception while serializing on client-side, code " << e.code << " (" << e.what() << ")";
+ throw t2n_serialization_error(msg.str());
+ }
+ catch(...)
+ { throw; }
std::ostream* ostr;
- if ((ostr=c.get_logstream(fulldebug))!=NULL)
+ if ((ostr=c->get_logstream(fulldebug))!=NULL)
{
(*ostr) << "sending command, decoded data: " << std::endl;
boost::archive::xml_oarchive xo(*ostr);
xo << BOOST_SERIALIZATION_NVP(cc);
}
- c.write(ofs.str());
-
- // TODO: fix timeout
- string resultpacket;
- while(!c.get_packet(resultpacket))
- c.fill_buffer();
+ c->write(ofs.str());
- istringstream ifs(resultpacket);
+ istringstream ifs(read_packet(command_timeout_usec));
boost::archive::binary_iarchive ia(ifs);
- // TODO: exceptions
- ia >> res;
+ try
+ {
+ ia >> res;
+ }
+ catch(boost::archive::archive_exception &e)
+ {
+ ostringstream msg;
+ msg << "archive_exception while deserializing on client-side, code " << e.code << " (" << e.what() << ")";
+ throw t2n_serialization_error(msg.str());
+ }
+ catch(...)
+ { throw; }
- if ((ostr=c.get_logstream(fulldebug))!=NULL)
+ if ((ostr=c->get_logstream(fulldebug))!=NULL)
{
(*ostr) << "received result, decoded data: " << std::endl;
boost::archive::xml_oarchive xo(*ostr);
git://developer.intra2net.com / libt2n / blobdiff