1 ------------------------------------------------------------------------------
3 -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- S Y S T E M . O S _ P R I M I T I V E S --
9 -- Copyright (C) 1998-2001 Free Software Foundation, Inc. --
11 -- GNARL 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 2, or (at your option) any later ver- --
14 -- sion. GNARL 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNARL; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNARL was developed by the GNARL team at Florida State University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 -- This version uses gettimeofday and select
35 -- Currently OpenNT, Dec Unix, Solaris and SCO UnixWare use this file.
37 package body System.OS_Primitives is
39 -- ??? These definitions are duplicated from System.OS_Interface
40 -- because we don't want to depend on any package. Consider removing
41 -- these declarations in System.OS_Interface and move these ones in
44 type struct_timezone is record
45 tz_minuteswest : Integer;
48 pragma Convention (C, struct_timezone);
49 type struct_timezone_ptr is access all struct_timezone;
51 type struct_timeval is record
55 pragma Convention (C, struct_timeval);
58 (tv : access struct_timeval;
59 tz : struct_timezone_ptr) return Integer;
60 pragma Import (C, gettimeofday, "gettimeofday");
62 type fd_set is null record;
63 type fd_set_ptr is access all fd_set;
69 exceptfds : fd_set_ptr := null;
70 timeout : access struct_timeval) return Integer;
71 pragma Import (C, C_select, "select");
77 function Clock return Duration is
78 TV : aliased struct_timeval;
82 Result := gettimeofday (TV'Access, null);
83 return Duration (TV.tv_sec) + Duration (TV.tv_usec) / 10#1#E6;
90 function Monotonic_Clock return Duration renames Clock;
103 Check_Time : Duration := Clock;
104 timeval : aliased struct_timeval;
107 if Mode = Relative then
109 Abs_Time := Time + Check_Time;
111 Rel_Time := Time - Check_Time;
115 if Rel_Time > 0.0 then
117 timeval.tv_sec := Integer (Rel_Time);
119 if Duration (timeval.tv_sec) > Rel_Time then
120 timeval.tv_sec := timeval.tv_sec - 1;
124 Integer ((Rel_Time - Duration (timeval.tv_sec)) * 10#1#E6);
126 Result := C_select (timeout => timeval'Unchecked_Access);
129 exit when Abs_Time <= Check_Time;
131 Rel_Time := Abs_Time - Check_Time;
136 end System.OS_Primitives;