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------------------------------------------------------------------------------
-- --
-- GNAT RUN-TIME COMPONENTS --
-- --
-- S Y S T E M . R A N D O M _ S E E D --
-- --
-- B o d y --
-- --
-- Copyright (C) 2011-2021, Free Software Foundation, Inc. --
-- --
-- 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. --
-- --
------------------------------------------------------------------------------
-- Version used on all systems except Ravenscar where Calendar is unavailable
with Ada.Calendar; use Ada.Calendar;
with Ada.Unchecked_Conversion;
package body System.Random_Seed is
Y2K : constant Time :=
Time_Of (Year => 2000, Month => 1, Day => 1, Seconds => 0.0);
-- First day of Year 2000, to get a duration
function To_U64 is
new Ada.Unchecked_Conversion (Duration, Interfaces.Unsigned_64);
--------------
-- Get_Seed --
--------------
function Get_Seed return Interfaces.Unsigned_64 is
begin
return To_U64 (Clock - Y2K);
end Get_Seed;
end System.Random_Seed;