BUG#28448258 - PREPARED STATEMENT FAILS FOR SET RESOURCE GROUP.

The SET RESOURCE GROUP doesn't support the prepared statment
protocol mode. The patch adds prepared statement support for
SET RESOURCE GROUP.

Author: thayumanavar77

mysql-test/include/resource_group_common.inc

@@ -341,3 +341,16 @@ SELECT func();
 SELECT COUNT(*) = 1 FROM performance_schema.threads WHERE RESOURCE_GROUP="Batch";
 DROP RESOURCE GROUP Batch FORCE;
 DROP FUNCTION func;
+
+
+#
+#  BUG#28448258 - PREPARED STATEMENT FAILS FOR SET RESOURCE GROUP
+#
+CREATE RESOURCE GROUP test TYPE = USER VCPU=2-3;
+SET @rg_name='test';
+SET @cmd = CONCAT("SET RESOURCE GROUP ", @rg_name);
+SELECT @cmd;
+PREPARE stmt FROM @cmd;
+EXECUTE stmt;
+SELECT COUNT(*) = 1 FROM performance_schema.threads WHERE RESOURCE_GROUP="test";
+DROP RESOURCE GROUP test FORCE;

mysql-test/r/resource_group.result

@@ -262,3 +262,15 @@ COUNT(*) = 1
 1
 DROP RESOURCE GROUP Batch FORCE;
 DROP FUNCTION func;
+CREATE RESOURCE GROUP test TYPE = USER VCPU=2-3;
+SET @rg_name='test';
+SET @cmd = CONCAT("SET RESOURCE GROUP ", @rg_name);
+SELECT @cmd;
+@cmd
+SET RESOURCE GROUP test
+PREPARE stmt FROM @cmd;
+EXECUTE stmt;
+SELECT COUNT(*) = 1 FROM performance_schema.threads WHERE RESOURCE_GROUP="test";
+COUNT(*) = 1
+1
+DROP RESOURCE GROUP test FORCE;

mysql-test/r/resource_group_thr_prio_unsupported.result

@@ -259,3 +259,15 @@ COUNT(*) = 1
 1
 DROP RESOURCE GROUP Batch FORCE;
 DROP FUNCTION func;
+CREATE RESOURCE GROUP test TYPE = USER VCPU=2-3;
+SET @rg_name='test';
+SET @cmd = CONCAT("SET RESOURCE GROUP ", @rg_name);
+SELECT @cmd;
+@cmd
+SET RESOURCE GROUP test
+PREPARE stmt FROM @cmd;
+EXECUTE stmt;
+SELECT COUNT(*) = 1 FROM performance_schema.threads WHERE RESOURCE_GROUP="test";
+COUNT(*) = 1
+1
+DROP RESOURCE GROUP test FORCE;

sql/resourcegroups/resource_group_sql_cmd.cc

@@ -604,16 +604,29 @@ static inline bool check_and_apply_resource_grp(
   return false;
 }
 
-bool resourcegroups::Sql_cmd_set_resource_group::execute(THD *thd) {
-  DBUG_ENTER("resourcegroups::Sql_cmd_set_resource_group::execute");
+/**
+  Check if user has sufficient privilege to exercise SET RESOURCE GROUP.
 
-  Security_context *sctx = thd->security_context();
+  @param sctx Pointer to security context.
+
+  @return true if sufficient privilege exists for SET RESOURCE GROUP else false.
+*/
+
+static bool check_resource_group_set_privilege(Security_context *sctx) {
   if (!(sctx->has_global_grant(STRING_WITH_LEN("RESOURCE_GROUP_ADMIN")).first ||
         sctx->has_global_grant(STRING_WITH_LEN("RESOURCE_GROUP_USER")).first)) {
     my_error(ER_SPECIFIC_ACCESS_DENIED_ERROR, MYF(0),
              "RESOURCE_GROUP_ADMIN OR RESOURCE_GROUP_USER");
-    DBUG_RETURN(true);
+    return true;
   }
+  return false;
+}
+
+bool resourcegroups::Sql_cmd_set_resource_group::execute(THD *thd) {
+  DBUG_ENTER("resourcegroups::Sql_cmd_set_resource_group::execute");
+
+  Security_context *sctx = thd->security_context();
+  if (check_resource_group_set_privilege(sctx)) DBUG_RETURN(true);
 
   // Acquire exclusive lock on the resource group name to synchronize with hint.
   if (acquire_exclusive_mdl_for_resource_group(thd, m_name.str))
@@ -701,3 +714,13 @@ bool resourcegroups::Sql_cmd_set_resource_group::execute(THD *thd) {
   my_ok(thd);
   DBUG_RETURN(false);
 }
+
+bool resourcegroups::Sql_cmd_set_resource_group::prepare(THD *thd) {
+  DBUG_ENTER("Sql_cmd_set_resource_group::prepare");
+
+  if (Sql_cmd::prepare(thd)) DBUG_RETURN(true);
+
+  bool rc = check_resource_group_set_privilege(thd->security_context());
+
+  DBUG_RETURN(rc);
+}

sql/resourcegroups/resource_group_sql_cmd.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+/* Copyright (c) 2018  Oracle and/or its affiliates. All rights reserved.
 
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
@@ -130,7 +130,7 @@ class Sql_cmd_drop_resource_group : public Sql_cmd {
   Sql_cmd_set_resource_group represents SET RESOURCE GROUP statement.
 */
 
-class Sql_cmd_set_resource_group : public Sql_cmd {
+class Sql_cmd_set_resource_group final : public Sql_cmd {
   friend class ::PT_set_resource_group;
 
  public:
@@ -143,6 +143,7 @@ class Sql_cmd_set_resource_group : public Sql_cmd {
   }
 
   bool execute(THD *thd) override;
+  bool prepare(THD *thd) override;
 
  private:
   const LEX_CSTRING m_name;

sql/sql_prepare.cc

@@ -1315,6 +1315,7 @@ static bool check_prepared_statement(Prepared_statement *stmt) {
     case SQLCOM_SHOW_FIELDS:
     case SQLCOM_SHOW_KEYS:
     case SQLCOM_CREATE_TABLE:
+    case SQLCOM_SET_RESOURCE_GROUP:
       res = lex->m_sql_cmd->prepare(thd);
       // @todo Temporary solution: Unprepare after preparation to preserve
       //       old behaviour