libt2n: (tomj) documented code problems; have to find out if this is the source of...

[libt2n] / src / command_client.cpp

diff --git a/src/command_client.cpp b/src/command_client.cpp
index 376d3f9..52ca0f1 100644 (file)
--- a/src/command_client.cpp
+++ b/src/command_client.cpp
@@ -39,25 +39,78 @@ using namespace std;
 namespace libt2n
 {
 
-command_client::command_client(client_connection& _c, long long _command_timeout_usec, long long _hello_timeout_usec)
+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);
+    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");
@@ -65,16 +118,20 @@ std::string command_client::read_packet(const long long &usec_timeout)
     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()
 {
     string resultpacket;
     bool got_packet=false;
     long long my_timeout=hello_timeout_usec;
-    while(!(got_packet=c.get_packet(resultpacket)) && my_timeout > 0  && !c.is_closed())
+    while(!(got_packet=c->get_packet(resultpacket)) && my_timeout > 0  && !c->is_closed())
     {
-        c.fill_buffer(my_timeout,&my_timeout);
+        c->fill_buffer(my_timeout,&my_timeout);
 
-        c.peek_packet(resultpacket);
+        c->peek_packet(resultpacket);
         check_hello(resultpacket);           // will throw before timeout if wrong data received
     }
 
@@ -85,7 +142,14 @@ void command_client::read_hello()
         throw t2n_version_mismatch("illegal hello received (incomplete): "+resultpacket);
 }
 
-bool command_client::check_hello(const string& hellostr)
+/** @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
+
+    @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);
 
@@ -160,12 +224,22 @@ bool command_client::check_hello(const string& hellostr)
     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);
 
+    if (is_connection_closed())
+        throw t2n_transfer_error("connection to server is closed");
+
     try
     {
         oa << cc;
@@ -180,14 +254,14 @@ void command_client::send_command(command* cmd, result_container &res)
         { 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());
+    c->write(ofs.str());
 
     istringstream ifs(read_packet(command_timeout_usec));
     boost::archive::binary_iarchive ia(ifs);
@@ -205,7 +279,7 @@ void command_client::send_command(command* cmd, result_container &res)
     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);