73 lines
4 KiB
Ada
73 lines
4 KiB
Ada
|
------------------------------------------------------------------------------
|
||
|
|
-- --
|
||
|
|
-- GNAT COMPILER COMPONENTS --
|
||
|
|
-- --
|
||
|
|
-- G N A T . L O C K _ F I L E S --
|
||
|
|
-- --
|
||
|
|
-- S p e c --
|
||
|
|
-- --
|
||
|
|
-- Copyright (C) 1995-2010, AdaCore --
|
||
|
|
-- --
|
||
|
|
-- GNAT is free software; you can redistribute it and/or modify it under --
|
||
|
|
-- terms of the GNU General Public License as published by the Free Soft- --
|
||
|
|
-- ware Foundation; either version 3, or (at your option) any later ver- --
|
||
|
|
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
|
||
|
|
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
|
||
|
|
-- or FITNESS FOR A PARTICULAR PURPOSE. --
|
||
|
|
-- --
|
||
|
|
-- As a special exception under Section 7 of GPL version 3, you are granted --
|
||
|
|
-- additional permissions described in the GCC Runtime Library Exception, --
|
||
|
|
-- version 3.1, as published by the Free Software Foundation. --
|
||
|
|
-- --
|
||
|
|
-- You should have received a copy of the GNU General Public License and --
|
||
|
|
-- a copy of the GCC Runtime Library Exception along with this program; --
|
||
|
|
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
|
||
|
|
-- <http://www.gnu.org/licenses/>. --
|
||
|
|
-- --
|
||
|
|
-- GNAT was originally developed by the GNAT team at New York University. --
|
||
|
|
-- Extensive contributions were provided by Ada Core Technologies Inc. --
|
||
|
|
-- --
|
||
|
|
------------------------------------------------------------------------------
|
||
|
|
|
||
|
|
-- This package contains the necessary routines for using files for the
|
||
|
|
-- purpose of providing reliable system wide locking capability.
|
||
|
|
|
||
|
|
package GNAT.Lock_Files is
|
||
|
|
pragma Preelaborate;
|
||
|
|
|
||
|
|
Lock_Error : exception;
|
||
|
|
-- Exception raised if file cannot be locked
|
||
|
|
|
||
|
|
subtype Path_Name is String;
|
||
|
|
-- Pathname is used by all services provided in this unit to specified
|
||
|
|
-- directory name and file name. On DOS based systems both directory
|
||
|
|
-- separators are handled (i.e. slash and backslash).
|
||
|
|
|
||
|
|
procedure Lock_File
|
||
|
|
(Directory : Path_Name;
|
||
|
|
Lock_File_Name : Path_Name;
|
||
|
|
Wait : Duration := 1.0;
|
||
|
|
Retries : Natural := Natural'Last);
|
||
|
|
-- Create a lock file Lock_File_Name in directory Directory. If the file
|
||
|
|
-- cannot be locked because someone already owns the lock, this procedure
|
||
|
|
-- waits Wait seconds and retries at most Retries times. If the file
|
||
|
|
-- still cannot be locked, Lock_Error is raised. The default is to try
|
||
|
|
-- every second, almost forever (Natural'Last times). The full path of
|
||
|
|
-- the file is constructed by concatenating Directory and Lock_File_Name.
|
||
|
|
-- Directory can optionally terminate with a directory separator.
|
||
|
|
|
||
|
|
procedure Lock_File
|
||
|
|
(Lock_File_Name : Path_Name;
|
||
|
|
Wait : Duration := 1.0;
|
||
|
|
Retries : Natural := Natural'Last);
|
||
|
|
-- See above. The full lock file path is given as one string
|
||
|
|
|
||
|
|
procedure Unlock_File (Directory : Path_Name; Lock_File_Name : Path_Name);
|
||
|
|
-- Unlock a file. Directory can optionally terminate with a directory
|
||
|
|
-- separator.
|
||
|
|
|
||
|
|
procedure Unlock_File (Lock_File_Name : Path_Name);
|
||
|
|
-- Unlock a file whose full path is given in Lock_File_Name
|
||
|
|
|
||
|
|
end GNAT.Lock_Files;
|