cleanup of pligin removal code

fixed multiple and missing deinitializations, moved all
deinit/del code in one place

sql/sql_plugin.cc

@@ -35,6 +35,11 @@ plugin_type_init plugin_type_initialize[MYSQL_MAX_PLUGIN_TYPE_NUM]=
   0,ha_initialize_handlerton,0
 };
 
+plugin_type_init plugin_type_deinitialize[MYSQL_MAX_PLUGIN_TYPE_NUM]=
+{
+  0,ha_finalize_handlerton,0
+};
+
 static const char *plugin_interface_version_sym=
                    "_mysql_plugin_interface_version_";
 static const char *sizeof_st_plugin_sym=
@@ -469,19 +474,36 @@ err:
 }
 
 
-void plugin_deinitializer(struct st_plugin_int *plugin)
+void plugin_deinitialize(struct st_plugin_int *plugin)
 {
+
+  if (plugin_type_deinitialize[plugin->plugin->type] &&
+      (*plugin_type_deinitialize[plugin->plugin->type])(plugin))
+  {
+    sql_print_error("Plugin '%s' of type %s failed deinitialization",
+                    plugin->name.str, plugin_type_names[plugin->plugin->type]);
+  }
+
   if (plugin->plugin->status_vars)
   {
+#ifdef FIX_LATER
+    /*
+      We have a problem right now where we can not prepend without
+      breaking backwards compatibility. We will fix this shortly so
+      that engines have "use names" and we wil use those for
+      CREATE TABLE, and use the plugin name then for adding automatic
+      variable names.
+    */
     SHOW_VAR array[2]= {
       {plugin->plugin->name, (char*)plugin->plugin->status_vars, SHOW_ARRAY},
       {0, 0, SHOW_UNDEF}
     };
     remove_status_vars(array);
+#else
+    remove_status_vars(plugin->plugin->status_vars);
+#endif /* FIX_LATER */
   }
 
-    if (plugin->state == PLUGIN_IS_READY)
-    {
   if (plugin->plugin->deinit)
   {
     DBUG_PRINT("info", ("Deinitializing plugin: '%s'", plugin->name.str));
@@ -492,26 +514,27 @@ void plugin_deinitializer(struct st_plugin_int *plugin)
     }
   }
   plugin->state= PLUGIN_IS_UNINITIALIZED;
-    }
 }
 
 
-static void plugin_del(const LEX_STRING *name)
+static void plugin_del(struct st_plugin_int *plugin)
 {
-  uint i;
-  struct st_plugin_int *plugin;
-  DBUG_ENTER("plugin_del");
-  if ((plugin= plugin_find_internal(name, MYSQL_ANY_PLUGIN)))
-  {
-    plugin_deinitializer(plugin);
+  DBUG_ENTER("plugin_del(plugin)");
   hash_delete(&plugin_hash[plugin->plugin->type], (byte*)plugin);
   plugin_dl_del(&plugin->plugin_dl->dl);
   plugin->state= PLUGIN_IS_FREED;
   plugin_array_version++;
-  }
   DBUG_VOID_RETURN;
 }
 
+static void plugin_del(const LEX_STRING *name)
+{
+  struct st_plugin_int *plugin;
+  DBUG_ENTER("plugin_del(name)");
+  if ((plugin= plugin_find_internal(name, MYSQL_ANY_PLUGIN)))
+    plugin_del(plugin);
+  DBUG_VOID_RETURN;
+}
 
 void plugin_unlock(struct st_plugin_int *plugin)
 {
@@ -521,9 +544,8 @@ void plugin_unlock(struct st_plugin_int *plugin)
   plugin->ref_count--;
   if (plugin->state == PLUGIN_IS_DELETED && ! plugin->ref_count)
   {
-    if (plugin->plugin->deinit)
-      plugin->plugin->deinit();
-    plugin_del(&plugin->name);
+    plugin_deinitialize(plugin);
+    plugin_del(plugin);
   }
   rw_unlock(&THR_LOCK_plugin);
   DBUG_VOID_RETURN;
@@ -545,7 +567,7 @@ static int plugin_initialize(struct st_plugin_int *plugin)
       variable names.
     */
     SHOW_VAR array[2]= {
-      {plugin->name, (char*)plugin->status_vars, SHOW_ARRAY},
+      {plugin->plugin->name, (char*)plugin->plugin->status_vars, SHOW_ARRAY},
       {0, 0, SHOW_UNDEF}
     };
     if (add_status_vars(array)) // add_status_vars makes a copy
@@ -578,53 +600,6 @@ err:
   DBUG_RETURN(1);
 }
 
-static int plugin_finalize(THD *thd, struct st_plugin_int *plugin)
-{
-  int rc;
-  DBUG_ENTER("plugin_finalize");
-
-  if (plugin->ref_count)
-  {
-    push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN, 0,
-                 "Plugin is busy and will be uninstalled on shutdown");
-    goto err;
-  }
-
-  switch (plugin->plugin->type)
-  {
-  case MYSQL_STORAGE_ENGINE_PLUGIN:
-    if (ha_finalize_handlerton(plugin))
-    {
-      push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN, 0,
-                   "Storage engine shutdown failed. "
-                   "It will be uninstalled on shutdown");
-      sql_print_warning("Storage engine '%s' shutdown failed. "
-                        "It will be uninstalled on shutdown", plugin->name.str);
-      goto err;
-    }
-    break;
-  default:
-    break;
-  }
-
-  if (plugin->plugin->deinit)
-  {
-    if ((rc= plugin->plugin->deinit()))
-    {
-      push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN, 0,
-                   "Plugin deinit failed. "
-                   "It will be uninstalled on shutdown");
-      sql_print_warning("Plugin '%s' deinit failed. "
-                        "It will be uninstalled on shutdown", plugin->name.str);
-      goto err;
-    }
-  }
-
-  DBUG_RETURN(0);
-err:
-  DBUG_RETURN(1);
-}
-
 static byte *get_hash_key(const byte *buff, uint *length,
                    my_bool not_used __attribute__((unused)))
 {
@@ -702,7 +677,10 @@ int plugin_init(int skip_dynamic_loading)
     if (tmp->state == PLUGIN_IS_UNINITIALIZED)
     {
       if (plugin_initialize(tmp))
-        plugin_del(&tmp->name);
+      {
+        plugin_deinitialize(tmp);
+        plugin_del(tmp);
+      }
     }
   }
 
@@ -812,7 +790,7 @@ void plugin_shutdown(void)
   {
     struct st_plugin_int *tmp= dynamic_element(&plugin_array, i,
                                                struct st_plugin_int *);
-    plugin_deinitializer(tmp);
+    plugin_deinitialize(tmp);
 
   }
 
@@ -862,7 +840,7 @@ my_bool mysql_install_plugin(THD *thd, const LEX_STRING *name, const LEX_STRING
   {
     my_error(ER_CANT_INITIALIZE_UDF, MYF(0), name->str,
              "Plugin initialization function failed.");
-    goto err;
+    goto deinit;
   }
 
   table->use_all_columns();
@@ -879,10 +857,9 @@ my_bool mysql_install_plugin(THD *thd, const LEX_STRING *name, const LEX_STRING
   rw_unlock(&THR_LOCK_plugin);
   DBUG_RETURN(FALSE);
 deinit:
-  if (tmp->plugin->deinit)
-    tmp->plugin->deinit();
+  plugin_deinitialize(tmp);
 err:
-  plugin_del(name);
+  plugin_del(tmp);
   rw_unlock(&THR_LOCK_plugin);
   DBUG_RETURN(TRUE);
 }
@@ -917,10 +894,17 @@ my_bool mysql_uninstall_plugin(THD *thd, const LEX_STRING *name)
     goto err;
   }
 
-  if (!plugin_finalize(thd, plugin))
-    plugin_del(name);
-  else
+  if (plugin->ref_count)
+  {
+    push_warning(thd, MYSQL_ERROR::WARN_LEVEL_WARN, 0,
+                 "Plugin is busy and will be uninstalled on shutdown");
     plugin->state= PLUGIN_IS_DELETED;
+  }
+  else
+  {
+    plugin_deinitialize(plugin);
+    plugin_del(plugin);
+  }
 
   table->use_all_columns();
   table->field[0]->store(name->str, name->length, system_charset_info);