File : a-catizo.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- A D A . C A L E N D A R . T I M E _ Z O N E S --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 2009-2012, Free Software Foundation, Inc. --
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 -- --
19 -- --
20 -- --
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 package body Ada.Calendar.Time_Zones is
33
34 --------------------------
35 -- Implementation Notes --
36 --------------------------
37
38 -- All operations in this package are target and time representation
39 -- independent, thus only one source file is needed for multiple targets.
40
41 ---------------------
42 -- UTC_Time_Offset --
43 ---------------------
44
45 function UTC_Time_Offset (Date : Time := Clock) return Time_Offset is
46 Offset_L : constant Long_Integer :=
47 Time_Zones_Operations.UTC_Time_Offset (Date);
48 Offset : Time_Offset;
49
50 begin
51 if Offset_L = Invalid_Time_Zone_Offset then
52 raise Unknown_Zone_Error;
53 end if;
54
55 -- The offset returned by Time_Zones_Operations.UTC_Time_Offset is in
56 -- seconds, the returned value needs to be in minutes.
57
58 Offset := Time_Offset (Offset_L / 60);
59
60 -- Validity checks
61
62 if not Offset'Valid then
63 raise Unknown_Zone_Error;
64 end if;
65
66 return Offset;
67 end UTC_Time_Offset;
68
69 end Ada.Calendar.Time_Zones;