Initial upstream commit

The history contained unlicensed code so everything got squashed, sorry.

Change-Id: Ie1335ecfcee7f740bb6de2e9887606be30a2deff
Signed-off-by: Nico Huber <nico.huber@secunet.com>
diff --git a/ada/clock_gettime/hw-time-timer.adb b/ada/clock_gettime/hw-time-timer.adb
new file mode 100644
index 0000000..914b201
--- /dev/null
+++ b/ada/clock_gettime/hw-time-timer.adb
@@ -0,0 +1,61 @@
+--
+-- Copyright (C) 2016 secunet Security Networks AG
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; version 2 of the License.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+
+with Interfaces.C;
+
+use type Interfaces.C.long;
+
+package body HW.Time.Timer
+with
+   Refined_State => (Timer_State => null,
+                     Abstract_Time => null)
+is
+   CLOCK_MONOTONIC_RAW : constant := 4;
+
+   subtype Clock_ID_T is Interfaces.C.int;
+   subtype Time_T is Interfaces.C.long;
+
+   type Struct_Timespec is record
+      TV_Sec   : aliased Time_T;
+      TV_NSec  : aliased Interfaces.C.long;
+   end record;
+   pragma Convention (C_Pass_By_Copy, Struct_Timespec);
+
+   function Clock_Gettime
+     (Clock_ID :        Clock_ID_T;
+      Timespec : access Struct_Timespec)
+      return Interfaces.C.int;
+   pragma Import (C, Clock_Gettime, "clock_gettime");
+
+   function Raw_Value_Min return T
+   is
+      Ignored : Interfaces.C.int;
+      Timespec : aliased Struct_Timespec;
+   begin
+      Ignored := Clock_Gettime (CLOCK_MONOTONIC_RAW, Timespec'Access);
+      return T (Timespec.TV_Sec * 1_000_000_000 + Timespec.TV_NSec);
+   end Raw_Value_Min;
+
+   function Raw_Value_Max return T
+   is
+   begin
+      return Raw_Value_Min + 1;
+   end Raw_Value_Max;
+
+   function Hz return T
+   is
+   begin
+      return 1_000_000_000; -- clock_gettime(2) is fixed to nanoseconds
+   end Hz;
+
+end HW.Time.Timer;