Bug#35078445 Please do not alter an existing service API

Revert extension of the mysql_command_factory service
introduced in WL#15396 (methods init_thread and deinit_thread).

Instead, declare a new service mysql_command_thread containing the two
methods.

Change-Id: I675f40ca4080adcf0ca464c3f3d9ff7fe8150479

Author: V S Murthy Sidagam

include/mysql/components/services/mysql_command_services.h

@@ -82,23 +82,6 @@ BEGIN_SERVICE_DEFINITION(mysql_command_factory)
 */
 DECLARE_BOOL_METHOD(init, (MYSQL_H * mysql_h));
 
-/**
-  Calls srv_session_init_thread() to initialize a thread to use the session
-  service.
-
-  @param[in] plugin A plugin structure pointer.
-
-    @retval true    failure
-    @retval false   success
-        */
-DECLARE_BOOL_METHOD(init_thread, (void *plugin));
-
-/**
-  Calls srv_session_deinit_thread() to deinitialize a thread that has been using
-  the session service.
-*/
-DECLARE_METHOD(void, deinit_thread, ());
-
 /**
   Calls mysql_real_connect api to connects to a MySQL server.
 
@@ -163,6 +146,31 @@ DECLARE_BOOL_METHOD(autocommit, (MYSQL_H mysql_h, bool mode));
 DECLARE_BOOL_METHOD(rollback, (MYSQL_H mysql_h));
 END_SERVICE_DEFINITION(mysql_command_factory)
 
+/**
+  @ingroup group_components_services_inventory
+
+  A service that provides the apis for mysql command session thread init and
+  thread end.
+
+*/
+BEGIN_SERVICE_DEFINITION(mysql_command_thread)
+
+/**
+  Calls session init_thread() to initialize a thread to use the session
+  service.
+
+  @retval true    failure
+  @retval false   success
+        */
+DECLARE_BOOL_METHOD(init, (void));
+
+/**
+  Calls session deinit_thread() to deinitialize a thread that has been using
+  the session service.
+*/
+DECLARE_METHOD(void, end, (void));
+END_SERVICE_DEFINITION(mysql_command_thread)
+
 /**
   @ingroup group_components_services_inventory
 

sql/server_component/mysql_command_services_imp.cc

@@ -78,25 +78,25 @@ DEFINE_BOOL_METHOD(mysql_command_services_imp::init, (MYSQL_H * mysql_h)) {
   return ret;
 }
 
+static MYSQL_LEX_CSTRING dummy_plugin{"server_service",
+                                      sizeof("server_service")};
 /**
-  Calls srv_session_init_thread() to initialize a thread to use the session
+  Calls session init_thread() to initialize a physical thread to use the session
   service.
 
-  @param[in] plugin A plugin structure pointer.
-
-    @retval true    failure
-    @retval false   success
+  @retval true    failure
+  @retval false   success
 */
-DEFINE_BOOL_METHOD(mysql_command_services_imp::init_thread, (void *plugin)) {
-  return srv_session_init_thread(plugin);
+DEFINE_BOOL_METHOD(mysql_command_services_imp::init, ()) {
+  return Srv_session::init_thread(&dummy_plugin);
 }
 
 /**
-  Calls srv_session_deinit_thread() to deinitialize a thread that has been using
-  the session service.
+  Calls session deinit_thread() to deinitialize a physical thread that has been
+  using the session service.
 */
-DEFINE_METHOD(void, mysql_command_services_imp::deinit_thread, ()) {
-  srv_session_deinit_thread();
+DEFINE_METHOD(void, mysql_command_services_imp::end, ()) {
+  Srv_session::deinit_thread();
 }
 
 /**

sql/server_component/mysql_command_services_imp.h

@@ -84,15 +84,17 @@ class mysql_command_services_imp {
  public:
   /* mysql_command_factory service apis */
   static DEFINE_BOOL_METHOD(init, (MYSQL_H * mysql_h));
-  static DEFINE_BOOL_METHOD(init_thread, (void *plugin));
-  static DEFINE_METHOD(void, deinit_thread, ());
   static DEFINE_BOOL_METHOD(connect, (MYSQL_H mysql_h));
   static DEFINE_BOOL_METHOD(reset, (MYSQL_H mysql_h));
   static DEFINE_BOOL_METHOD(close, (MYSQL_H mysql_h));
   static DEFINE_BOOL_METHOD(commit, (MYSQL_H mysql_h));
   static DEFINE_BOOL_METHOD(autocommit, (MYSQL_H mysql_h, bool mode));
   static DEFINE_BOOL_METHOD(rollback, (MYSQL_H mysql_h));
 
+  /* mysql_command_thread service apis */
+  static DEFINE_BOOL_METHOD(init, (void));
+  static DEFINE_METHOD(void, end, (void));
+
   /* mysql_command_options service apis */
   static DEFINE_BOOL_METHOD(set, (MYSQL_H mysql, int option, const void *arg));
   static DEFINE_BOOL_METHOD(get, (MYSQL_H mysql, int option, const void *arg));

sql/server_component/server_component.cc

@@ -461,13 +461,15 @@ mysql_audit_print_service_double_data_source_imp::get
 END_SERVICE_IMPLEMENTATION();
 
 BEGIN_SERVICE_IMPLEMENTATION(mysql_server, mysql_command_factory)
-mysql_command_services_imp::init, mysql_command_services_imp::init_thread,
-    mysql_command_services_imp::deinit_thread,
-    mysql_command_services_imp::connect, mysql_command_services_imp::reset,
-    mysql_command_services_imp::close, mysql_command_services_imp::commit,
-    mysql_command_services_imp::autocommit,
+mysql_command_services_imp::init, mysql_command_services_imp::connect,
+    mysql_command_services_imp::reset, mysql_command_services_imp::close,
+    mysql_command_services_imp::commit, mysql_command_services_imp::autocommit,
     mysql_command_services_imp::rollback END_SERVICE_IMPLEMENTATION();
 
+BEGIN_SERVICE_IMPLEMENTATION(mysql_server, mysql_command_thread)
+mysql_command_services_imp::init,
+    mysql_command_services_imp::end END_SERVICE_IMPLEMENTATION();
+
 BEGIN_SERVICE_IMPLEMENTATION(mysql_server, mysql_command_options)
 mysql_command_services_imp::set,
     mysql_command_services_imp::get END_SERVICE_IMPLEMENTATION();
@@ -696,6 +698,7 @@ PROVIDES_SERVICE(mysql_server_path_filter, dynamic_loader_scheme_file),
     PROVIDES_SERVICE(mysql_server,
                      mysql_audit_print_service_double_data_source),
     PROVIDES_SERVICE(mysql_server, mysql_command_factory),
+    PROVIDES_SERVICE(mysql_server, mysql_command_thread),
     PROVIDES_SERVICE(mysql_server, mysql_command_options),
     PROVIDES_SERVICE(mysql_server, mysql_command_query),
     PROVIDES_SERVICE(mysql_server, mysql_command_query_result),

sql/srv_session.cc

@@ -624,6 +624,10 @@ static void set_psi(THD *thd) {
 */
 bool Srv_session::init_thread(const void *plugin) {
   char stack_start;
+
+  /* If not null, means its already initialized, so return success*/
+  if (THR_srv_session_thread != nullptr) return false;
+
   if (my_thread_init()) {
     connection_errors_internal++;
     return true;
@@ -679,7 +683,10 @@ static void close_all_sessions_of_plugin_if_any(const st_plugin_int *plugin) {
 */
 void Srv_session::deinit_thread() {
   const st_plugin_int *plugin = THR_srv_session_thread;
-  if (plugin) close_currently_attached_session_if_any(plugin);
+  if (plugin)
+    close_currently_attached_session_if_any(plugin);
+  else
+    return;
 
   if (server_session_threads.remove(my_thread_self()))
     LogErr(ERROR_LEVEL, ER_FAILED_TO_DECREMENT_NUMBER_OF_THREADS);