111
|
1 ------------------------------------------------------------------------------
|
|
2 -- --
|
|
3 -- GNAT COMPILER COMPONENTS --
|
|
4 -- --
|
|
5 -- G N A T . L O C K _ F I L E S --
|
|
6 -- --
|
|
7 -- S p e c --
|
|
8 -- --
|
131
|
9 -- Copyright (C) 1995-2018, AdaCore --
|
111
|
10 -- --
|
|
11 -- GNAT is free software; you can redistribute it and/or modify it under --
|
|
12 -- terms of the GNU General Public License as published by the Free Soft- --
|
|
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
|
|
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
|
|
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
|
|
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
|
|
17 -- --
|
|
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
|
|
19 -- additional permissions described in the GCC Runtime Library Exception, --
|
|
20 -- version 3.1, as published by the Free Software Foundation. --
|
|
21 -- --
|
|
22 -- You should have received a copy of the GNU General Public License and --
|
|
23 -- a copy of the GCC Runtime Library Exception along with this program; --
|
|
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
|
|
25 -- <http://www.gnu.org/licenses/>. --
|
|
26 -- --
|
|
27 -- GNAT was originally developed by the GNAT team at New York University. --
|
|
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
|
|
29 -- --
|
|
30 ------------------------------------------------------------------------------
|
|
31
|
|
32 -- This package contains the necessary routines for using files for the
|
|
33 -- purpose of providing reliable system wide locking capability.
|
|
34
|
|
35 package GNAT.Lock_Files is
|
|
36 pragma Preelaborate;
|
|
37
|
|
38 Lock_Error : exception;
|
|
39 -- Exception raised if file cannot be locked
|
|
40
|
|
41 subtype Path_Name is String;
|
|
42 -- Pathname is used by all services provided in this unit to specify
|
|
43 -- directory name and file name. On DOS based systems both directory
|
|
44 -- separators are handled (i.e. slash and backslash).
|
|
45
|
|
46 procedure Lock_File
|
|
47 (Directory : Path_Name;
|
|
48 Lock_File_Name : Path_Name;
|
|
49 Wait : Duration := 1.0;
|
|
50 Retries : Natural := Natural'Last);
|
|
51 -- Create a lock file Lock_File_Name in directory Directory. If the file
|
|
52 -- cannot be locked because someone already owns the lock, this procedure
|
|
53 -- waits Wait seconds and retries at most Retries times. If the file
|
|
54 -- still cannot be locked, Lock_Error is raised. The default is to try
|
|
55 -- every second, almost forever (Natural'Last times). The full path of
|
|
56 -- the file is constructed by concatenating Directory and Lock_File_Name.
|
|
57 -- Directory can optionally terminate with a directory separator.
|
|
58
|
|
59 procedure Lock_File
|
|
60 (Lock_File_Name : Path_Name;
|
|
61 Wait : Duration := 1.0;
|
|
62 Retries : Natural := Natural'Last);
|
|
63 -- See above. The full lock file path is given as one string
|
|
64
|
|
65 procedure Unlock_File (Directory : Path_Name; Lock_File_Name : Path_Name);
|
|
66 -- Unlock a file. Directory can optionally terminate with a directory
|
|
67 -- separator.
|
|
68
|
|
69 procedure Unlock_File (Lock_File_Name : Path_Name);
|
|
70 -- Unlock a file whose full path is given in Lock_File_Name
|
|
71
|
|
72 end GNAT.Lock_Files;
|