Bug#35058647 split Forwarder, Sender and Receiver classes

The classic_auth_*.h files contain both Sender's and Forwarder classes.

- The Sender classes inherit from Processor.
- The Forwarder classes inherit from ForwardingProcessor.

In most cases, only the Sender _or_ the Forwarder classes are used.

Change
------

- move the Sender classes to <prefix>_sender.cc
- move the Forwarder classes to <prefix>_forwarder.cc

Change-Id: I28bc8c17e86a7cfbdc0098afe72fa19413c870ee

router/src/routing/src/CMakeLists.txt

@@ -61,36 +61,54 @@ ADD_LIBRARY(routing SHARED
   classic_auth.cc
   classic_auth_cleartext.cc
   classic_auth_caching_sha2.cc
-  classic_auth_forwarder.cc
   classic_auth_native.cc
   classic_auth_sha256_password.cc
-  classic_binlog_dump.cc
-  classic_change_user.cc
-  classic_clone.cc
   classic_command.cc
   classic_connect.cc
   classic_flow.cc
   classic_forwarder.cc
   classic_frame.cc
-  classic_greeting.cc
-  classic_init_schema.cc
-  classic_kill.cc
   classic_lazy_connect.cc
-  classic_list_fields.cc
-  classic_ping.cc
-  classic_query.cc
-  classic_quit.cc
-  classic_register_replica.cc
-  classic_reload.cc
-  classic_reset_connection.cc
-  classic_set_option.cc
-  classic_statistics.cc
-  classic_stmt_close.cc
-  classic_stmt_execute.cc
-  classic_stmt_fetch.cc
-  classic_stmt_param_append_data.cc
-  classic_stmt_prepare.cc
-  classic_stmt_reset.cc
+
+  classic_auth_cleartext_forwarder.cc
+  classic_auth_caching_sha2_forwarder.cc
+  classic_auth_forwarder.cc
+  classic_auth_native_forwarder.cc
+  classic_auth_sha256_password_forwarder.cc
+  classic_binlog_dump_forwarder.cc
+  classic_change_user_forwarder.cc
+  classic_clone_forwarder.cc
+  classic_greeting_forwarder.cc
+  classic_init_schema_forwarder.cc
+  classic_kill_forwarder.cc
+  classic_list_fields_forwarder.cc
+  classic_ping_forwarder.cc
+  classic_query_forwarder.cc
+  classic_quit_forwarder.cc
+  classic_register_replica_forwarder.cc
+  classic_reload_forwarder.cc
+  classic_reset_connection_forwarder.cc
+  classic_set_option_forwarder.cc
+  classic_statistics_forwarder.cc
+  classic_stmt_close_forwarder.cc
+  classic_stmt_execute_forwarder.cc
+  classic_stmt_fetch_forwarder.cc
+  classic_stmt_param_append_data_forwarder.cc
+  classic_stmt_prepare_forwarder.cc
+  classic_stmt_reset_forwarder.cc
+
+  classic_auth_cleartext_sender.cc
+  classic_auth_caching_sha2_sender.cc
+  classic_auth_native_sender.cc
+  classic_auth_sha256_password_sender.cc
+  classic_change_user_sender.cc
+  # classic_greeting_sender.cc
+  classic_init_schema_sender.cc
+  classic_query_sender.cc
+  classic_quit_sender.cc
+  classic_reset_connection_sender.cc
+
+  classic_greeting_receiver.cc
 
   sql_value.cc
 )