------------------------------------------------------------------------------
--                              Ada Web Server                              --
--                                                                          --
--                         Copyright (C) 2000-2001                          --
--                                ACT-Europe                                --
--                                                                          --
--  Authors: Dmitriy Anisimkov - Pascal Obry                                --
--                                                                          --
--  This library 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; either version 2 of the License, or (at   --
--  your option) any later version.                                         --
--                                                                          --
--  This library 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.                                --
--                                                                          --
--  You should have received a copy of the GNU General Public License       --
--  along with this library; if not, write to the Free Software Foundation, --
--  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.          --
--                                                                          --
--  As a special exception, if other files instantiate generics from this   --
--  unit, or you link this unit with other files to produce an executable,  --
--  this  unit  does not  by itself cause  the resulting executable to be   --
--  covered by the GNU General Public License. This exception does not      --
--  however invalidate any other reasons why the executable file  might be  --
--  covered by the  GNU Public License.                                     --
------------------------------------------------------------------------------

--  $Id: aws-os_lib.adb,v 1.1 2003/10/05 19:59:45 Jano Exp $

--  Use the OS support routines in GNAT.OS_Lib instead of the POSIX library
--  and get the current UTC/GMT time from the C library.

with GNAT.OS_Lib;

package body AWS.OS_Lib is

   function OS_Time_To_Calendar_Time (UTC : in GNAT.OS_Lib.OS_Time)
     return Ada.Calendar.Time;
   --  Returns a Calendar.Time from an OS_Time variable.

   ------------------
   -- Is_Directory --
   ------------------

   function Is_Directory (Filename : in String) return Boolean
     renames GNAT.OS_Lib.Is_Directory;

   ---------------------
   -- Is_Regular_File --
   ---------------------

   function Is_Regular_File (Filename : in String) return Boolean
     renames GNAT.OS_Lib.Is_Regular_File;

   ---------------
   -- File_Size --
   ---------------

   function File_Size (Filename : in String)
     return Ada.Streams.Stream_Element_Offset
   is
      use GNAT.OS_Lib;

      Name    : String := Filename & ASCII.NUL;
      FD      : File_Descriptor;
      Length  : Ada.Streams.Stream_Element_Offset := 0;
   begin
      FD := Open_Read (Name'Address, Binary);
      if FD /= Invalid_FD then
         Length := Ada.Streams.Stream_Element_Offset (File_Length (FD));
         Close (FD);
         return Length;
      end if;
      raise No_Such_File;
   end File_Size;

   --------------------
   -- File_Timestamp --
   --------------------

   function File_Timestamp (Filename : in String) return Ada.Calendar.Time is
   begin
      return OS_Time_To_Calendar_Time (GNAT.OS_Lib.File_Time_Stamp (Filename));
   exception
      when others =>
         raise No_Such_File;
   end File_Timestamp;

   ---------------
   -- GMT_Clock --
   ---------------

   function GMT_Clock return Ada.Calendar.Time is
      type OS_Time_A is access all GNAT.OS_Lib.OS_Time;

      function C_Time (Time : OS_Time_A) return GNAT.OS_Lib.OS_Time;
      pragma Import (C, C_Time, "time");

   begin
      return OS_Time_To_Calendar_Time (C_Time (null));
   end GMT_Clock;

   ------------------------------
   -- OS_Time_To_Calendar_Time --
   ------------------------------

   function OS_Time_To_Calendar_Time (UTC : in GNAT.OS_Lib.OS_Time)
      return Ada.Calendar.Time
   is
      Year   : Integer;
      Month  : Integer;
      Day    : Integer;
      Hour   : Integer;
      Minute : Integer;
      Second : Integer;
   begin
      GNAT.OS_Lib.GM_Split (UTC, Year, Month, Day, Hour, Minute, Second);
      return Ada.Calendar.Time_Of (Year, Month, Day,
                                   Duration (Hour   * 3600 +
                                             Minute * 60 +
                                             Second));
   end OS_Time_To_Calendar_Time;

end AWS.OS_Lib;