=== modified file 'include/mysql/plugin.h'
--- include/mysql/plugin.h	2008-03-07 21:46:29 +0000
+++ include/mysql/plugin.h	2009-02-11 19:09:32 +0000
@@ -168,7 +168,7 @@ struct st_mysql_value;
 */
 
 typedef int (*mysql_var_check_func)(MYSQL_THD thd,
-                                    struct st_mysql_sys_var *var,
+                                    class sys_var_pluginvar *var,
                                     void *save, struct st_mysql_value *value);
 
 /*
@@ -186,7 +186,7 @@ typedef int (*mysql_var_check_func)(MYSQ
    For example, strings may require memory to be allocated.
 */
 typedef void (*mysql_var_update_func)(MYSQL_THD thd,
-                                      struct st_mysql_sys_var *var,
+                                      class sys_var_pluginvar *var,
                                       void *var_ptr, const void *save);
 
 

=== modified file 'mysql-test/r/plugin.result'
--- mysql-test/r/plugin.result	2008-02-24 13:12:17 +0000
+++ mysql-test/r/plugin.result	2009-02-11 19:18:06 +0000
@@ -25,7 +25,7 @@ INSTALL PLUGIN example SONAME 'ha_exampl
 SET GLOBAL example_enum_var= e1;
 SET GLOBAL example_enum_var= e2;
 SET GLOBAL example_enum_var= impossible;
-ERROR 42000: Variable 'enum_var' can't be set to the value of 'impossible'
+ERROR 42000: Variable 'example_enum_var' can't be set to the value of 'impossible'
 UNINSTALL PLUGIN example;
 INSTALL PLUGIN example SONAME 'ha_example.so';
 select @@session.sql_mode into @old_sql_mode;
@@ -36,7 +36,7 @@ select @@global.example_ulong_var;
 500
 set global example_ulong_var=1111;
 Warnings:
-Warning	1292	Truncated incorrect ulong_var value: '1111'
+Warning	1292	Truncated incorrect example_ulong_var value: '1111'
 select @@global.example_ulong_var;
 @@global.example_ulong_var
 1000
@@ -46,7 +46,7 @@ select @@global.example_ulong_var;
 @@global.example_ulong_var
 500
 set global example_ulong_var=1111;
-ERROR 42000: Variable 'ulong_var' can't be set to the value of '1111'
+ERROR 42000: Variable 'example_ulong_var' can't be set to the value of '1111'
 select @@global.example_ulong_var;
 @@global.example_ulong_var
 500

=== modified file 'sql/sql_plugin.cc'
--- sql/sql_plugin.cc	2009-02-09 15:03:52 +0000
+++ sql/sql_plugin.cc	2009-02-11 19:16:41 +0000
@@ -1871,7 +1871,7 @@ typedef uchar *(*mysql_sys_var_ptr_p)(vo
   default variable data check and update functions
 ****************************************************************************/
 
-static int check_func_bool(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_bool(THD *thd, sys_var_pluginvar *var,
                            void *save, st_mysql_value *value)
 {
   char buff[STRING_BUFFER_USUAL_SIZE];
@@ -1910,66 +1910,66 @@ err:
 }
 
 
-static int check_func_int(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_int(THD *thd, sys_var_pluginvar *var,
                           void *save, st_mysql_value *value)
 {
   my_bool fixed;
   long long tmp;
   struct my_option options;
   value->val_int(value, &tmp);
-  plugin_opt_set_limits(&options, var);
+  plugin_opt_set_limits(&options, var->plugin_var);
 
-  if (var->flags & PLUGIN_VAR_UNSIGNED)
+  if (var->plugin_var->flags & PLUGIN_VAR_UNSIGNED)
     *(uint *)save= (uint) getopt_ull_limit_value((ulonglong) tmp, &options,
                                                    &fixed);
   else
     *(int *)save= (int) getopt_ll_limit_value(tmp, &options, &fixed);
 
-  return throw_bounds_warning(thd, fixed, var->flags & PLUGIN_VAR_UNSIGNED,
+  return throw_bounds_warning(thd, fixed, var->plugin_var->flags & PLUGIN_VAR_UNSIGNED,
                               var->name, (longlong) tmp);
 }
 
 
-static int check_func_long(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_long(THD *thd, sys_var_pluginvar *var,
                           void *save, st_mysql_value *value)
 {
   my_bool fixed;
   long long tmp;
   struct my_option options;
   value->val_int(value, &tmp);
-  plugin_opt_set_limits(&options, var);
+  plugin_opt_set_limits(&options, var->plugin_var);
 
-  if (var->flags & PLUGIN_VAR_UNSIGNED)
+  if (var->plugin_var->flags & PLUGIN_VAR_UNSIGNED)
     *(ulong *)save= (ulong) getopt_ull_limit_value((ulonglong) tmp, &options,
                                                    &fixed);
   else
     *(long *)save= (long) getopt_ll_limit_value(tmp, &options, &fixed);
 
-  return throw_bounds_warning(thd, fixed, var->flags & PLUGIN_VAR_UNSIGNED,
+  return throw_bounds_warning(thd, fixed, var->plugin_var->flags & PLUGIN_VAR_UNSIGNED,
                               var->name, (longlong) tmp);
 }
 
 
-static int check_func_longlong(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_longlong(THD *thd, sys_var_pluginvar *var,
                                void *save, st_mysql_value *value)
 {
   my_bool fixed;
   long long tmp;
   struct my_option options;
   value->val_int(value, &tmp);
-  plugin_opt_set_limits(&options, var);
+  plugin_opt_set_limits(&options, var->plugin_var);
 
-  if (var->flags & PLUGIN_VAR_UNSIGNED)
+  if (var->plugin_var->flags & PLUGIN_VAR_UNSIGNED)
     *(ulonglong *)save= getopt_ull_limit_value((ulonglong) tmp, &options,
                                                &fixed);
   else
     *(longlong *)save= getopt_ll_limit_value(tmp, &options, &fixed);
 
-  return throw_bounds_warning(thd, fixed, var->flags & PLUGIN_VAR_UNSIGNED,
+  return throw_bounds_warning(thd, fixed, var->plugin_var->flags & PLUGIN_VAR_UNSIGNED,
                               var->name, (longlong) tmp);
 }
 
-static int check_func_str(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_str(THD *thd, sys_var_pluginvar *var,
                           void *save, st_mysql_value *value)
 {
   char buff[STRING_BUFFER_USUAL_SIZE];
@@ -1984,7 +1984,7 @@ static int check_func_str(THD *thd, stru
 }
 
 
-static int check_func_enum(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_enum(THD *thd, sys_var_pluginvar *var,
                            void *save, st_mysql_value *value)
 {
   char buff[STRING_BUFFER_USUAL_SIZE];
@@ -1994,10 +1994,10 @@ static int check_func_enum(THD *thd, str
   long result;
   int length;
 
-  if (var->flags & PLUGIN_VAR_THDLOCAL)
-    typelib= ((thdvar_enum_t*) var)->typelib;
+  if (var->plugin_var->flags & PLUGIN_VAR_THDLOCAL)
+    typelib= ((thdvar_enum_t*) var->plugin_var)->typelib;
   else
-    typelib= ((sysvar_enum_t*) var)->typelib;
+    typelib= ((sysvar_enum_t*) var->plugin_var)->typelib;
 
   if (value->value_type(value) == MYSQL_VALUE_TYPE_STRING)
   {
@@ -2030,7 +2030,7 @@ err:
 }
 
 
-static int check_func_set(THD *thd, struct st_mysql_sys_var *var,
+static int check_func_set(THD *thd, sys_var_pluginvar *var,
                           void *save, st_mysql_value *value)
 {
   char buff[STRING_BUFFER_USUAL_SIZE], *error= 0;
@@ -2041,7 +2041,7 @@ static int check_func_set(THD *thd, stru
   bool not_used;
   int length;
 
-  if (var->flags & PLUGIN_VAR_THDLOCAL)
+  if (var->plugin_var->flags & PLUGIN_VAR_THDLOCAL)
     typelib= ((thdvar_set_t*) var)->typelib;
   else
     typelib= ((sysvar_set_t*)var)->typelib;
@@ -2080,40 +2080,40 @@ err:
 }
 
 
-static void update_func_bool(THD *thd, struct st_mysql_sys_var *var,
+static void update_func_bool(THD *thd, sys_var_pluginvar *var,
                              void *tgt, const void *save)
 {
   *(my_bool *) tgt= *(my_bool *) save ? TRUE : FALSE;
 }
 
 
-static void update_func_int(THD *thd, struct st_mysql_sys_var *var,
+static void update_func_int(THD *thd, sys_var_pluginvar *var,
                              void *tgt, const void *save)
 {
   *(int *)tgt= *(int *) save;
 }
 
 
-static void update_func_long(THD *thd, struct st_mysql_sys_var *var,
+static void update_func_long(THD *thd, sys_var_pluginvar *var,
                              void *tgt, const void *save)
 {
   *(long *)tgt= *(long *) save;
 }
 
 
-static void update_func_longlong(THD *thd, struct st_mysql_sys_var *var,
+static void update_func_longlong(THD *thd, sys_var_pluginvar *var,
                              void *tgt, const void *save)
 {
   *(longlong *)tgt= *(ulonglong *) save;
 }
 
 
-static void update_func_str(THD *thd, struct st_mysql_sys_var *var,
+static void update_func_str(THD *thd, sys_var_pluginvar *var,
                              void *tgt, const void *save)
 {
   char *old= *(char **) tgt;
   *(char **)tgt= *(char **) save;
-  if (var->flags & PLUGIN_VAR_MEMALLOC)
+  if (var->plugin_var->flags & PLUGIN_VAR_MEMALLOC)
   {
     *(char **)tgt= my_strdup(*(char **) save, MYF(0));
     my_free(old, MYF(0));
@@ -2660,7 +2660,7 @@ bool sys_var_pluginvar::check(THD *thd, 
   value.item= var->value;
 
   return is_readonly() ||
-         plugin_var->check(thd, plugin_var, &var->save_result, &value);
+         plugin_var->check(thd, this, &var->save_result, &value);
 }
 
 
@@ -2716,13 +2716,13 @@ void sys_var_pluginvar::set_default(THD 
 
   if (!(plugin_var->flags & PLUGIN_VAR_THDLOCAL) || type == OPT_GLOBAL)
   {
-    plugin_var->update(thd, plugin_var, tgt, src);
+    plugin_var->update(thd, this, tgt, src);
     pthread_mutex_unlock(&LOCK_global_system_variables);
   }
   else
   {
     pthread_mutex_unlock(&LOCK_global_system_variables);
-    plugin_var->update(thd, plugin_var, tgt, src);
+    plugin_var->update(thd, this, tgt, src);
   }
 }
 
@@ -2746,13 +2746,13 @@ bool sys_var_pluginvar::update(THD *thd,
   if (!(plugin_var->flags & PLUGIN_VAR_THDLOCAL) || var->type == OPT_GLOBAL)
   {
     /* variable we are updating has global scope, so we unlock after updating */
-    plugin_var->update(thd, plugin_var, tgt, &var->save_result);
+    plugin_var->update(thd, this, tgt, &var->save_result);
     pthread_mutex_unlock(&LOCK_global_system_variables);
   }
   else
   {
     pthread_mutex_unlock(&LOCK_global_system_variables);
-    plugin_var->update(thd, plugin_var, tgt, &var->save_result);
+    plugin_var->update(thd, this, tgt, &var->save_result);
   }
  return 0;
 }