query_classifier.cc:parsing_info_done: calling mysql_thread_end caused segfauls when same thread tried next time call free_embedded_thd because thread's sysvar was set to NULL in mysql_thread_end.

Added a few lines to canonical query test's input script which are not handled correctly.

log_manager/test/makefile

@@ -39,7 +39,7 @@ buildtests:
 	-o testlog \
 	-I$(MARIADB_SRC_PATH)/include \
 	-I$(LOG_MANAGER_PATH) -I$(UTILS_PATH) testlog.c \
-	-llog_manager $(LDLIBS) \
+	-lstdc++ -llog_manager $(LDLIBS) \
 	$(UTILS_PATH)/skygw_utils.o
 
 

query_classifier/query_classifier.cc

@@ -964,9 +964,8 @@ parsing_info_t* parsing_info_init(
                         mysql_errno(mysql),
                                                  mysql_error(mysql))));
                 
-                mysql_library_end();
                 goto retblock;
-        }                
+        }
         /** Set methods and authentication to mysql */
         mysql_options(mysql, MYSQL_READ_DEFAULT_GROUP, "libmysqld_skygw");
         mysql_options(mysql, MYSQL_OPT_USE_EMBEDDED_CONNECTION, NULL);
@@ -1019,7 +1018,6 @@ void parsing_info_done(
                         mysql->thd = NULL;
                 }
                 mysql_close(mysql);
-                mysql_thread_end();
         }
         /** Free plain text query string */
         if (pi->pi_query_plain_str != NULL)

query_classifier/test/canonical_tests/input.sql

@@ -4,3 +4,7 @@ select 1,2,3,4,5,6 from tst;
 select * from tst where fname like '%a%';
 select * from tst where lname like '%e%' order by fname;
 insert into tst values ("John","Doe"),("Plato",null),("Nietzsche","");
+select  md5("200000foo") =10, sleep(2), rand(100);
+select * from my1 where md5("110") =10;
+select  md5("100foo") =10;
+select * from my1 where md5("100") =10;