MXS-1267: Use local client in tee

The tee filter now uses the local client class to clone the queries. This
imposes some restrictions on how the filter can be used but also makes
MaxScale as a whole more robust.

server/modules/filter/tee/CMakeLists.txt

@@ -1,4 +1,4 @@
-add_library(tee SHARED tee.cc)
-target_link_libraries(tee maxscale-common)
+add_library(tee SHARED tee.cc local_client.cc)
+target_link_libraries(tee maxscale-common MySQLCommon)
 set_target_properties(tee PROPERTIES VERSION "1.0.0")
 install_module(tee core)

server/modules/filter/tee/local_client.cc

@@ -34,10 +34,10 @@ LocalClient::LocalClient(MXS_SESSION* session, int fd):
 {
     MXS_POLL_DATA::handler = LocalClient::poll_handler;
     MySQLProtocol* client = (MySQLProtocol*)m_session->client_dcb->protocol;
-    m_proto = {};
-    m_proto.charset = client->charset;
-    m_proto.client_capabilities = client->client_capabilities;
-    m_proto.extra_capabilities = client->extra_capabilities;
+    m_protocol = {};
+    m_protocol.charset = client->charset;
+    m_protocol.client_capabilities = client->client_capabilities;
+    m_protocol.extra_capabilities = client->extra_capabilities;
 }
 
 LocalClient::~LocalClient()
@@ -48,7 +48,7 @@ LocalClient::~LocalClient()
     }
 }
 
-bool LocalClient::query(GWBUF* buffer)
+bool LocalClient::queue_query(GWBUF* buffer)
 {
     GWBUF* my_buf = gwbuf_clone(buffer);
 
@@ -82,9 +82,9 @@ void LocalClient::process(uint32_t events)
         {
             if (m_state == VC_WAITING_HANDSHAKE)
             {
-                if (gw_decode_mysql_server_handshake(&m_proto, GWBUF_DATA(buf) + MYSQL_HEADER_LEN) == 0)
+                if (gw_decode_mysql_server_handshake(&m_protocol, GWBUF_DATA(buf) + MYSQL_HEADER_LEN) == 0)
                 {
-                    GWBUF* response = gw_generate_auth_response(m_session, &m_proto, false, false);
+                    GWBUF* response = gw_generate_auth_response(m_session, &m_protocol, false, false);
                     m_queue.push_front(response);
                     m_state = VC_RESPONSE_SENT;
                 }

server/modules/filter/tee/local_client.hh

@@ -46,7 +46,7 @@ public:
      *
      * @return True if query was successfully queued
      */
-    bool query(GWBUF* buffer);
+    bool queue_query(GWBUF* buffer);
 
 private:
     LocalClient(MXS_SESSION* session, int fd);
@@ -71,5 +71,5 @@ private:
     size_t                  m_expected_bytes;
     std::deque<mxs::Buffer> m_queue;
     MXS_SESSION*            m_session;
-    MySQLProtocol           m_proto;
+    MySQLProtocol           m_protocol;
 };