don't rely on readdir() returning . and .. first

sql/sql_base.cc

@@ -2255,9 +2255,15 @@ static void mysql_rm_tmp_tables(void)
   ** Remove all SQLxxx tables from directory
   */
 
-  for (idx=2 ; idx < (uint) dirp->number_off_files ; idx++)
+  for (idx=0 ; idx < (uint) dirp->number_off_files ; idx++)
   {
     file=dirp->dir_entry+idx;
+
+    /* skiping . and .. */
+    if (file->name[0] == '.' && (!file->name[1] ||
+       (file->name[1] == '.' &&  !file->name[2])))
+      continue;
+
     if (!bcmp(file->name,tmp_file_prefix,tmp_file_prefix_length))
     {
       sprintf(filePath,"%s%s",mysql_tmpdir,file->name); /* purecov: inspected */

sql/sql_db.cc

@@ -237,7 +237,7 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db,
 
   tot_list_next= &tot_list;
 
-  for (uint idx=2 ;
+  for (uint idx=0 ;
        idx < (uint) dirp->number_off_files && !thd->killed ;
        idx++)
   {
@@ -245,6 +245,11 @@ static long mysql_rm_known_files(THD *thd, MY_DIR *dirp, const char *db,
     char *extension;
     DBUG_PRINT("info",("Examining: %s", file->name));
 
+    /* skiping . and .. */
+    if (file->name[0] == '.' && (!file->name[1] ||
+       (file->name[1] == '.' &&  !file->name[2])))
+      continue;
+
     /* Check if file is a raid directory */
     if ((isdigit(file->name[0]) ||
 	 (file->name[0] >= 'a' && file->name[0] <= 'f')) &&