Make query classifier self-contained.

Only the query classifier needs the functionality of the embedded
server, while the rest of MaxScale is content with the client
library or Connector/C.

This have now been rearranged so that query-classifier links with
the embedded static library and then explicitly exports its own
functions using the query_classifier.map linker script. That way
query classifier will use the embedded library, while the rest of
maxscale use the client library, and this without conflicts.

Currently, query_classifier is not linked to maxscale-common,
but executables must link to maxscale-common and query_classifier.

query_classifier/CMakeLists.txt

@@ -1,6 +1,9 @@
 add_library(query_classifier SHARED query_classifier.cc)
-target_link_libraries(query_classifier maxscale-common)
+
+target_link_libraries(query_classifier ${EMBEDDED_LIB} aio crypt crypto dl m ${PCRE_LINK_FLAGS} ssl stdc++ z)
 set_target_properties(query_classifier PROPERTIES VERSION "1.0.0")
+set_target_properties(query_classifier PROPERTIES LINK_FLAGS -Wl,--version-script=${CMAKE_CURRENT_SOURCE_DIR}/query_classifier.map)
+#set_target_properties(query_classifier PROPERTIES LINK_FLAGS -Wl,-z,defs)
 install(TARGETS query_classifier COMPONENT lib DESTINATION ${MAXSCALE_LIBDIR})
 if(BUILD_TESTS)
   add_subdirectory(test)

query_classifier/query_classifier.cc

@@ -46,6 +46,11 @@
 #include <sql_parse.h>
 #include <errmsg.h>
 #include <client_settings.h>
+// In client_settings.h mysql_server_init and mysql_server_end are defined to
+// mysql_client_plugin_init and mysql_client_plugin_deinit respectively.
+// Those must be undefined, so that we here really call mysql_server_[init|end].
+#undef mysql_server_init
+#undef mysql_server_end
 #include <set_var.h>
 #include <strfunc.h>
 #include <item_func.h>
@@ -1478,14 +1483,13 @@ static parsing_info_t* parsing_info_init(void (*donefun)(void *))
 
     /** Get server handle */
     mysql = mysql_init(NULL);
-    ss_dassert(mysql != NULL);
 
     if (mysql == NULL)
     {
         MXS_ERROR("Call to mysql_real_connect failed due %d, %s.",
                   mysql_errno(mysql),
                   mysql_error(mysql));
-
+        ss_dassert(mysql != NULL);
         goto retblock;
     }
 
@@ -1770,3 +1774,42 @@ qc_query_op_t qc_get_operation(GWBUF* querybuf)
 
     return operation;
 }
+
+
+bool qc_init(int argc, char** argv, char** groups)
+{
+    int rc = mysql_library_init(argc, argv, groups);
+
+    if (rc != 0)
+    {
+        MXS_ERROR("mysql_library_init() failed. Error code: %d", rc);
+    }
+    else
+    {
+        MXS_NOTICE("Query classifier initialized.");
+    }
+
+    return rc == 0;
+}
+
+void qc_end()
+{
+    mysql_library_end();
+}
+
+bool qc_thread_init()
+{
+    bool inited = (mysql_thread_init() == 0);
+
+    if (!inited)
+    {
+        MXS_ERROR("mysql_thread_init() failed.");
+    }
+
+    return inited;
+}
+
+void qc_thread_end()
+{
+    mysql_thread_end();
+}

query_classifier/query_classifier.h

@@ -83,6 +83,12 @@ typedef enum
 
 #define QUERY_IS_TYPE(mask,type) ((mask & type) == type)
 
+bool qc_init(int argc, char** argv, char** groups);
+void qc_end();
+
+bool qc_thread_init();
+void qc_thread_end();
+
 /**
  * Create THD and use it for creating parse tree. Examine parse tree and
  * classify the query.

query_classifier/query_classifier.map

@@ -0,0 +1,20 @@
+{
+    global:
+        qc_end;
+        qc_get_affected_fields;
+        qc_get_canonical;
+        qc_get_created_table_name;
+        qc_get_database_names;
+        qc_get_operation;
+        qc_get_qtype_str;
+        qc_get_table_names;
+        qc_get_type;
+        qc_init;
+        qc_is_drop_table_query;
+        qc_is_real_query;
+        qc_query_has_clause;
+        qc_thread_end;
+        qc_thread_init;
+    local:
+        *;
+};

server/core/CMakeLists.txt

@@ -1,6 +1,6 @@
 add_library(maxscale-common SHARED adminusers.c atomic.c buffer.c config.c dbusers.c dcb.c filter.c externcmd.c gwbitmask.c gwdirs.c gw_utils.c hashtable.c hint.c housekeeper.c load_utils.c maxscale_pcre2.c memlog.c modutil.c monitor.c poll.c random_jkiss.c resultset.c secrets.c server.c service.c session.c spinlock.c thread.c users.c utils.c ${CMAKE_SOURCE_DIR}/log_manager/log_manager.cc ${CMAKE_SOURCE_DIR}/utils/skygw_utils.cc)
 
-target_link_libraries(maxscale-common ${EMBEDDED_LIB} ${LZMA_LINK_FLAGS} ${PCRE2_LIBRARIES} ${PCRE_LINK_FLAGS} ${CURL_LIBRARIES} ssl aio pthread crypt dl crypto inih z rt m stdc++)
+target_link_libraries(maxscale-common ${MYSQLCLIENT_LIBRARIES} ${LZMA_LINK_FLAGS} ${PCRE2_LIBRARIES} ${CURL_LIBRARIES} ssl aio pthread crypt dl crypto inih z rt m stdc++)
 
 if(WITH_JEMALLOC)
   target_link_libraries(maxscale-common ${JEMALLOC_LIBRARIES})
@@ -20,15 +20,15 @@ elseif(WITH_TCMALLOC)
   target_link_libraries(maxscale ${TCMALLOC_LIBRARIES})
 endif()
 
-target_link_libraries(maxscale maxscale-common)
+target_link_libraries(maxscale maxscale-common query_classifier)
 install(TARGETS maxscale DESTINATION ${MAXSCALE_BINDIR})
 
 add_executable(maxkeys maxkeys.c)
-target_link_libraries(maxkeys maxscale-common)
+target_link_libraries(maxkeys maxscale-common query_classifier)
 install(TARGETS maxkeys DESTINATION ${MAXSCALE_BINDIR})
 
 add_executable(maxpasswd maxpasswd.c)
-target_link_libraries(maxpasswd maxscale-common)
+target_link_libraries(maxpasswd maxscale-common query_classifier)
 install(TARGETS maxpasswd DESTINATION ${MAXSCALE_BINDIR})
 
 if(BUILD_TESTS)

server/core/gateway.c

@@ -79,8 +79,9 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
-# include <skygw_utils.h>
-# include <log_manager.h>
+#include <skygw_utils.h>
+#include <log_manager.h>
+#include <query_classifier.h>
 
 #include <execinfo.h>
 
@@ -990,17 +991,26 @@ static void usage(void)
  */
 void worker_thread_main(void* arg)
 {
-    /** Init mysql thread context for use with a mysql handle and a parser */
-    if (mysql_thread_init() == 0)
+    if (qc_thread_init())
     {
-        poll_waitevents(arg);
+        /** Init mysql thread context for use with a mysql handle and a parser */
+        if (mysql_thread_init() == 0)
+        {
+            poll_waitevents(arg);
 
-        /** Release mysql thread context */
-        mysql_thread_end();
+            /** Release mysql thread context */
+            mysql_thread_end();
+        }
+        else
+        {
+            MXS_ERROR("Could not perform thread initialization for MySQL. Exiting thread.");
+        }
+
+        qc_thread_end();
     }
     else
     {
-        MXS_ERROR("Could not perform thread initialization for MySQL. Exiting thread.");
+        MXS_ERROR("Could not perform thread initialization for query classifier. Exiting thread.");
     }
 }
 
@@ -1818,6 +1828,14 @@ int main(int argc, char **argv)
         }
     }
 
+    if (!qc_init(num_elements, server_options, server_groups))
+    {
+        char* logerr = "Failed to initialise query classifier library.";
+        print_log_n_stderr(true, true, logerr, logerr, eno);
+        rc = MAXSCALE_INTERNALERROR;
+        goto return_main;
+    }
+
     if (mysql_library_init(num_elements, server_options, server_groups))
     {
         if (!daemon_mode)

server/core/poll.c

@@ -36,6 +36,7 @@
 #include <mysql.h>
 #include <resultset.h>
 #include <session.h>
+#include <query_classifier.h>
 
 #define         PROFILE_POLL    0
 

server/core/test/CMakeLists.txt

@@ -15,22 +15,22 @@ add_executable(test_users testusers.c)
 add_executable(testfeedback testfeedback.c)
 add_executable(testmaxscalepcre2 testmaxscalepcre2.c)
 add_executable(testmemlog testmemlog.c)
-target_link_libraries(test_adminusers maxscale-common)
-target_link_libraries(test_buffer maxscale-common)
-target_link_libraries(test_dcb maxscale-common)
-target_link_libraries(test_filter maxscale-common)
-target_link_libraries(test_hash maxscale-common )
-target_link_libraries(test_hint maxscale-common )
-target_link_libraries(test_modutil maxscale-common)
-target_link_libraries(test_mysql_users MySQLClient maxscale-common)
-target_link_libraries(test_poll maxscale-common)
-target_link_libraries(test_server maxscale-common)
-target_link_libraries(test_service maxscale-common)
-target_link_libraries(test_spinlock maxscale-common )
-target_link_libraries(test_users maxscale-common)
-target_link_libraries(testfeedback maxscale-common)
-target_link_libraries(testmaxscalepcre2 maxscale-common )
-target_link_libraries(testmemlog maxscale-common )
+target_link_libraries(test_adminusers maxscale-common query_classifier)
+target_link_libraries(test_buffer maxscale-common query_classifier)
+target_link_libraries(test_dcb maxscale-common query_classifier)
+target_link_libraries(test_filter maxscale-common query_classifier)
+target_link_libraries(test_hash maxscale-common query_classifier)
+target_link_libraries(test_hint maxscale-common query_classifier)
+target_link_libraries(test_modutil maxscale-common query_classifier)
+target_link_libraries(test_mysql_users MySQLClient maxscale-common query_classifier)
+target_link_libraries(test_poll maxscale-common query_classifier)
+target_link_libraries(test_server maxscale-common query_classifier)
+target_link_libraries(test_service maxscale-common query_classifier)
+target_link_libraries(test_spinlock maxscale-common query_classifier)
+target_link_libraries(test_users maxscale-common query_classifier)
+target_link_libraries(testfeedback maxscale-common query_classifier)
+target_link_libraries(testmaxscalepcre2 maxscale-common query_classifier)
+target_link_libraries(testmemlog maxscale-common query_classifier)
 add_test(Internal-TestAdminUsers test_adminusers)
 add_test(Internal-TestBuffer test_buffer)
 add_test(Internal-TestDCB test_dcb)

server/modules/filter/test/CMakeLists.txt

@@ -1,8 +1,8 @@
 include_directories(${CMAKE_CURRENT_SOURCE_DIR})
 add_executable(harness_ui harness_ui.c harness_common.c)
 add_executable(harness harness_util.c harness_common.c)
-target_link_libraries(harness_ui maxscale-common)
-target_link_libraries(harness maxscale-common)
+target_link_libraries(harness_ui maxscale-common query_classifier)
+target_link_libraries(harness maxscale-common query_classifier)
 execute_process(COMMAND ${CMAKE_COMMAND} -E copy ${ERRMSG} ${CMAKE_CURRENT_BINARY_DIR})
 execute_process(COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/harness.cnf ${CMAKE_CURRENT_BINARY_DIR})
 configure_file(${CMAKE_CURRENT_SOURCE_DIR}/testdriver.sh ${CMAKE_CURRENT_BINARY_DIR}/testdriver.sh @ONLY)

server/modules/routing/binlog/CMakeLists.txt

@@ -4,7 +4,7 @@ target_link_libraries(binlogrouter maxscale-common)
 install(TARGETS binlogrouter DESTINATION ${MAXSCALE_LIBDIR})
 
 add_executable(maxbinlogcheck maxbinlogcheck.c blr_file.c blr_cache.c blr_master.c blr_slave.c blr.c)
-target_link_libraries(maxbinlogcheck maxscale-common)
+target_link_libraries(maxbinlogcheck maxscale-common query_classifier)
 
 install(TARGETS maxbinlogcheck DESTINATION bin)
 

server/modules/routing/binlog/test/CMakeLists.txt

@@ -1,5 +1,5 @@
 if(BUILD_TESTS)
   add_executable(testbinlogrouter testbinlog.c ../blr.c ../blr_slave.c ../blr_master.c ../blr_file.c ../blr_cache.c)
-  target_link_libraries(testbinlogrouter maxscale-common)
+  target_link_libraries(testbinlogrouter maxscale-common query_classifier)
   add_test(TestBinlogRouter ${CMAKE_CURRENT_BINARY_DIR}/testbinlogrouter)
 endif()