gcc/ada/g-calend.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                         G N A T . C A L E N D A R                        --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                            $Revision: 1.1 $
  10 --                                                                          --
  11 --          Copyright (C) 1999-2001 Free Software Foundation, Inc.          --
  12 --                                                                          --
  13 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  14 -- terms of the  GNU General Public License as published  by the Free Soft- --
  15 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  16 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  17 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  18 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  19 -- for  more details.  You should have  received  a copy of the GNU General --
  20 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  21 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  22 -- MA 02111-1307, USA.                                                      --
  23 --                                                                          --
  24 -- As a special exception,  if other files  instantiate  generics from this --
  25 -- unit, or you link  this unit with other files  to produce an executable, --
  26 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  27 -- covered  by the  GNU  General  Public  License.  This exception does not --
  28 -- however invalidate  any other reasons why  the executable file  might be --
  29 -- covered by the  GNU Public License.                                      --
  30 --                                                                          --
  31 -- GNAT was originally developed  by the GNAT team at  New York University. --
  32 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  33 --                                                                          --
  34 ------------------------------------------------------------------------------
  35
  36 --  This package extends Ada.Calendar to handle Hour, Minute, Second,
  37 --  Second_Duration and Day_Of_Week and Day_In_Year from Calendar.Time.
  38 --  Second_Duration precision depends on the target clock precision.
  39 --
  40 --  GNAT.Calendar provides the same kind of abstraction found in
  41 --  Ada.Calendar. It provides Split and Time_Of to build and split a Time
  42 --  data. And it provides accessor functions to get only one of Hour, Minute,
  43 --  Second, Second_Duration. Other functions are to access more advanced
  44 --  valueas like Day_Of_Week, Day_In_Year and Week_In_Year.
  45
  46 with Ada.Calendar;
  47 with Interfaces.C;
  48
  49 package GNAT.Calendar is
  50
  51    type Day_Name is
  52      (Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday);
  53
  54    subtype Hour_Number         is Natural range 0 .. 23;
  55    subtype Minute_Number       is Natural range 0 .. 59;
  56    subtype Second_Number       is Natural range 0 .. 59;
  57    subtype Second_Duration     is Ada.Calendar.Day_Duration range 0.0 .. 1.0;
  58    subtype Day_In_Year_Number  is Positive range 1 .. 366;
  59    subtype Week_In_Year_Number is Positive range 1 .. 53;
  60
  61    function Hour       (Date : Ada.Calendar.Time) return Hour_Number;
  62    function Minute     (Date : Ada.Calendar.Time) return Minute_Number;
  63    function Second     (Date : Ada.Calendar.Time) return Second_Number;
  64    function Sub_Second (Date : Ada.Calendar.Time) return Second_Duration;
  65    --  Hour, Minute, Sedond and Sub_Second returns the complete time data for
  66    --  the Date (H:M:S.SS). See Ada.Calendar for Year, Month, Day accessors.
  67    --  Second_Duration precision depends on the target clock precision.
  68
  69    function Day_Of_Week (Date : Ada.Calendar.Time) return Day_Name;
  70    --  Return the day name.
  71
  72    function Day_In_Year (Date : Ada.Calendar.Time) return Day_In_Year_Number;
  73    --  Returns the day number in the year. (1st January is day 1 and 31st
  74    --  December is day 365 or 366 for leap year).
  75
  76    function Week_In_Year (Date : Ada.Calendar.Time) return Week_In_Year_Number;
  77    --  Returns the week number in the year with Monday as first day of week
  78
  79    procedure Split
  80      (Date       : Ada.Calendar.Time;
  81       Year       : out Ada.Calendar.Year_Number;
  82       Month      : out Ada.Calendar.Month_Number;
  83       Day        : out Ada.Calendar.Day_Number;
  84       Hour       : out Hour_Number;
  85       Minute     : out Minute_Number;
  86       Second     : out Second_Number;
  87       Sub_Second : out Second_Duration);
  88    --  Split the standard Ada.Calendar.Time data in date data (Year, Month,
  89    --  Day) and Time data (Hour, Minute, Second, Sub_Second)
  90
  91    function Time_Of
  92      (Year       : Ada.Calendar.Year_Number;
  93       Month      : Ada.Calendar.Month_Number;
  94       Day        : Ada.Calendar.Day_Number;
  95       Hour       : Hour_Number;
  96       Minute     : Minute_Number;
  97       Second     : Second_Number;
  98       Sub_Second : Second_Duration := 0.0)
  99       return Ada.Calendar.Time;
 100    --  Returns an Ada.Calendar.Time data built from the date and time values.
 101
 102    --  C timeval conversion
 103
 104    --  C timeval represent a duration (used in Select for example). This
 105    --  structure is composed of a number of seconds and a number of micro
 106    --  seconds. The timeval structure is not exposed here because its
 107    --  definition is target dependent. Interface to C programs is done via a
 108    --  pointer to timeval structure.
 109
 110    type timeval is private;
 111
 112    function To_Duration (T : access timeval) return Duration;
 113    function To_Timeval  (D : Duration) return timeval;
 114
 115 private
 116    --  This is a dummy declaration that should be the largest possible timeval
 117    --  structure of all supported targets.
 118
 119    type timeval is array (1 .. 2) of Interfaces.C.long;
 120
 121    function Julian_Day
 122      (Year  : Ada.Calendar.Year_Number;
 123       Month : Ada.Calendar.Month_Number;
 124       Day   : Ada.Calendar.Day_Number)
 125       return  Integer;
 126    --  Compute Julian day number.
 127    --
 128    --  The code of this function is a modified version of algorithm
 129    --  199 from the Collected Algorithms of the ACM.
 130    --  The author of algorithm 199 is Robert G. Tantzen.
 131 end GNAT.Calendar;