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 --
11 -- Copyright (C) 1998-2001 Free Software Foundation, Inc. --
13 -- GNARL 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. GNARL 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 GNARL; see file COPYING. If not, write --
21 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
22 -- MA 02111-1307, USA. --
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. --
31 -- GNARL was developed by the GNARL team at Florida State University. It is --
32 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
33 -- State University (http://www.gnat.com). --
35 ------------------------------------------------------------------------------
37 -- This version uses gettimeofday and select
38 -- Currently OpenNT, Dec Unix, Solaris and SCO UnixWare use this file.
40 package body System.OS_Primitives is
42 -- ??? These definitions are duplicated from System.OS_Interface
43 -- because we don't want to depend on any package. Consider removing
44 -- these declarations in System.OS_Interface and move these ones in
47 type struct_timezone is record
48 tz_minuteswest : Integer;
51 pragma Convention (C, struct_timezone);
52 type struct_timezone_ptr is access all struct_timezone;
54 type struct_timeval is record
58 pragma Convention (C, struct_timeval);
61 (tv : access struct_timeval;
62 tz : struct_timezone_ptr) return Integer;
63 pragma Import (C, gettimeofday, "gettimeofday");
65 type fd_set is null record;
66 type fd_set_ptr is access all fd_set;
72 exceptfds : fd_set_ptr := null;
73 timeout : access struct_timeval) return Integer;
74 pragma Import (C, C_select, "select");
80 function Clock return Duration is
81 TV : aliased struct_timeval;
85 Result := gettimeofday (TV'Access, null);
86 return Duration (TV.tv_sec) + Duration (TV.tv_usec) / 10#1#E6;
93 function Monotonic_Clock return Duration renames Clock;
106 Check_Time : Duration := Clock;
107 timeval : aliased struct_timeval;
110 if Mode = Relative then
112 Abs_Time := Time + Check_Time;
114 Rel_Time := Time - Check_Time;
118 if Rel_Time > 0.0 then
120 timeval.tv_sec := Integer (Rel_Time);
122 if Duration (timeval.tv_sec) > Rel_Time then
123 timeval.tv_sec := timeval.tv_sec - 1;
127 Integer ((Rel_Time - Duration (timeval.tv_sec)) * 10#1#E6);
129 Result := C_select (timeout => timeval'Unchecked_Access);
132 exit when Abs_Time <= Check_Time;
134 Rel_Time := Abs_Time - Check_Time;
139 end System.OS_Primitives;