File : a-calcon.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- A D A . C A L E N D A R . C O N V E R S I O N S --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 2008-2014, 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 -- This package provides various routines for conversion between Ada and Unix
33 -- time models - Time, Duration, struct tm and struct timespec.
34
35 with Interfaces.C;
36
37 package Ada.Calendar.Conversions is
38
39 function To_Ada_Time (Unix_Time : Interfaces.C.long) return Time;
40 -- Convert a time value represented as number of seconds since the
41 -- Unix Epoch to a time value relative to an Ada implementation-defined
42 -- Epoch. The units of the result are nanoseconds on all targets. Raises
43 -- Time_Error if the result cannot fit into a Time value.
44
45 function To_Ada_Time
46 (tm_year : Interfaces.C.int;
47 tm_mon : Interfaces.C.int;
48 tm_day : Interfaces.C.int;
49 tm_hour : Interfaces.C.int;
50 tm_min : Interfaces.C.int;
51 tm_sec : Interfaces.C.int;
52 tm_isdst : Interfaces.C.int) return Time;
53 -- Convert a time value expressed in Unix-like fields of struct tm into
54 -- a Time value relative to the Ada Epoch. The ranges of the formals are
55 -- as follows:
56
57 -- tm_year -- years since 1900
58 -- tm_mon -- months since January [0 .. 11]
59 -- tm_day -- day of the month [1 .. 31]
60 -- tm_hour -- hours since midnight [0 .. 24]
61 -- tm_min -- minutes after the hour [0 .. 59]
62 -- tm_sec -- seconds after the minute [0 .. 60]
63 -- tm_isdst -- Daylight Savings Time flag [-1 .. 1]
64
65 -- The returned value is in UTC and may or may not contain leap seconds
66 -- depending on whether binder flag "-y" was used. Raises Time_Error if
67 -- the input values are out of the defined ranges or if tm_sec equals 60
68 -- and the instance in time is not a leap second occurrence.
69
70 function To_Duration
71 (tv_sec : Interfaces.C.long;
72 tv_nsec : Interfaces.C.long) return Duration;
73 -- Convert an elapsed time value expressed in Unix-like fields of struct
74 -- timespec into a Duration value. The expected ranges are:
75
76 -- tv_sec - seconds
77 -- tv_nsec - nanoseconds
78
79 procedure To_Struct_Timespec
80 (D : Duration;
81 tv_sec : out Interfaces.C.long;
82 tv_nsec : out Interfaces.C.long);
83 -- Convert a Duration value into the constituents of struct timespec.
84 -- Formal tv_sec denotes seconds and tv_nsecs denotes nanoseconds.
85
86 procedure To_Struct_Tm
87 (T : Time;
88 tm_year : out Interfaces.C.int;
89 tm_mon : out Interfaces.C.int;
90 tm_day : out Interfaces.C.int;
91 tm_hour : out Interfaces.C.int;
92 tm_min : out Interfaces.C.int;
93 tm_sec : out Interfaces.C.int);
94 -- Convert a Time value set in the Ada Epoch into the constituents of
95 -- struct tm. The ranges of the out formals are as follows:
96
97 -- tm_year -- years since 1900
98 -- tm_mon -- months since January [0 .. 11]
99 -- tm_day -- day of the month [1 .. 31]
100 -- tm_hour -- hours since midnight [0 .. 24]
101 -- tm_min -- minutes after the hour [0 .. 59]
102 -- tm_sec -- seconds after the minute [0 .. 60]
103 -- tm_isdst -- Daylight Savings Time flag [-1 .. 1]
104
105 -- The input date is considered to be in UTC
106
107 function To_Unix_Time (Ada_Time : Time) return Interfaces.C.long;
108 -- Convert a time value represented as number of time units since the Ada
109 -- implementation-defined Epoch to a value relative to the Unix Epoch. The
110 -- units of the result are seconds. Raises Time_Error if the result cannot
111 -- fit into a Time value.
112
113 end Ada.Calendar.Conversions;