Fixed bug #30287.

The server created temporary tables for filesort in the working directory
instead of the specified tmpdir directory.


sql/item.cc:
  Fixed bug #30287.
  The Item_field::set_field method has been modified to reset the any_privileges
  flag to false in case of system temporary table. This modification prevents the
  server from unnecessary checking of user privileges to access system temporary
  tables.
sql/sql_select.cc:
  Fixed bug #30287.
  Bugfix for #29015 has been removed: TABLE_SHARE::table_name of system
  temporary tables contains full path to table file basename again.
sql/sql_view.cc:
  Fixed bug #30287.
  Commentary has been added.

sql/item.cc

@@ -1765,6 +1765,8 @@ void Item_field::set_field(Field *field_par)
   unsigned_flag=test(field_par->flags & UNSIGNED_FLAG);
   collation.set(field_par->charset(), field_par->derivation());
   fixed= 1;
+  if (field->table->s->tmp_table == SYSTEM_TMP_TABLE)
+    any_privileges= 0;
 }
 
 

sql/sql_select.cc

@@ -9169,7 +9169,7 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
   bool  using_unique_constraint= 0;
   bool  use_packed_rows= 0;
   bool  not_all_columns= !(select_options & TMP_TABLE_ALL_COLUMNS);
-  char	*tmpname, *tmppath, path[FN_REFLEN], table_name[NAME_LEN+1];
+  char  *tmpname,path[FN_REFLEN];
   byte	*pos,*group_buff;
   uchar *null_flags;
   Field **reg_field, **from_field, **default_field;
@@ -9192,12 +9192,12 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
     temp_pool_slot = bitmap_set_next(&temp_pool);
 
   if (temp_pool_slot != MY_BIT_NONE) // we got a slot
-    sprintf(table_name, "%s_%lx_%i", tmp_file_prefix,
+    sprintf(path, "%s_%lx_%i", tmp_file_prefix,
             current_pid, temp_pool_slot);
   else
   {
     /* if we run out of slots or we are not using tempool */
-    sprintf(table_name, "%s%lx_%lx_%x", tmp_file_prefix,current_pid,
+    sprintf(path,"%s%lx_%lx_%x", tmp_file_prefix,current_pid,
             thd->thread_id, thd->tmp_table++);
   }
 
@@ -9205,8 +9205,8 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
     No need to change table name to lower case as we are only creating
     MyISAM or HEAP tables here
   */
-  fn_format(path, table_name, mysql_tmpdir, "",
-            MY_REPLACE_EXT|MY_UNPACK_FILENAME);
+  fn_format(path, path, mysql_tmpdir, "", MY_REPLACE_EXT|MY_UNPACK_FILENAME);
+
 
   if (group)
   {
@@ -9251,8 +9251,7 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
                         sizeof(*key_part_info)*(param->group_parts+1),
                         &param->start_recinfo,
                         sizeof(*param->recinfo)*(field_count*2+4),
-                        &tmppath, (uint) strlen(path)+1,
-                        &tmpname, (uint) strlen(table_name)+1,
+                        &tmpname, (uint) strlen(path)+1,
                         &group_buff, group && ! using_unique_constraint ?
                         param->group_length : 0,
                         NullS))
@@ -9270,8 +9269,7 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
     DBUG_RETURN(NULL);				/* purecov: inspected */
   }
   param->items_to_copy= copy_func;
-  strmov(tmppath, path);
-  strmov(tmpname, table_name);
+  strmov(tmpname,path);
   /* make table according to fields */
 
   bzero((char*) table,sizeof(*table));
@@ -9297,8 +9295,7 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
 
   table->s= &table->share_not_to_be_used;
   table->s->blob_field= blob_field;
-  table->s->table_name= tmpname;
-  table->s->path= tmppath;
+  table->s->table_name= table->s->path= tmpname;
   table->s->db= "";
   table->s->blob_ptr_size= mi_portable_sizeof_char_ptr;
   table->s->tmp_table= NON_TRANSACTIONAL_TMP_TABLE;

sql/sql_view.cc

@@ -397,9 +397,15 @@ bool mysql_create_view(THD *thd, TABLE_LIST *views,
     {
       Item_field *field;
       if ((field= item->filed_for_view_update()))
+      {
+        /*
+         any_privileges may be reset later by the Item_field::set_field
+         method in case of a system temporary table.
+        */
         field->any_privileges= 1;
       }
     }
+  }
 #endif
 
   if (open_and_lock_tables(thd, tables))