1------------------------------------------------------------------------------
2--                                                                          --
3--                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
4--                                                                          --
5--                  S Y S T E M . O S _ P R I M I T I V E S                 --
6--                                                                          --
7--                                  B o d y                                 --
8--                                                                          --
9--          Copyright (C) 1998-2008, Free Software Foundation, Inc.         --
10--                                                                          --
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 3,  or (at your option) any later ver- --
14-- sion.  GNAT 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.                                     --
17--                                                                          --
18-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
21--                                                                          --
22-- You should have received a copy of the GNU General Public License and    --
23-- a copy of the GCC Runtime Library Exception along with this program;     --
24-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
25-- <http://www.gnu.org/licenses/>.                                          --
26--                                                                          --
27-- GNARL was developed by the GNARL team at Florida State University.       --
28-- Extensive contributions were provided by Ada Core Technologies, Inc.     --
29--                                                                          --
30------------------------------------------------------------------------------
31
32--  This version is for darwin
33
34package body System.OS_Primitives is
35
36   --  ??? These definitions are duplicated from System.OS_Interface
37   --  because we don't want to depend on any package. Consider removing
38   --  these declarations in System.OS_Interface and move these ones in
39   --  the spec.
40
41   type struct_timezone is record
42      tz_minuteswest  : Integer;
43      tz_dsttime   : Integer;
44   end record;
45   pragma Convention (C, struct_timezone);
46   type struct_timezone_ptr is access all struct_timezone;
47
48   type time_t is new Long_Integer;
49
50   type struct_timeval is record
51      tv_sec       : time_t;
52      tv_usec      : Integer;
53   end record;
54   pragma Convention (C, struct_timeval);
55
56   function gettimeofday
57     (tv : not null access struct_timeval;
58      tz : struct_timezone_ptr) return Integer;
59   pragma Import (C, gettimeofday, "gettimeofday");
60
61   type timespec is record
62      tv_sec  : time_t;
63      tv_nsec : Long_Integer;
64   end record;
65   pragma Convention (C, timespec);
66
67   function nanosleep (rqtp, rmtp : not null access timespec) return Integer;
68   pragma Import (C, nanosleep, "nanosleep");
69
70   -----------
71   -- Clock --
72   -----------
73
74   function Clock return Duration is
75      TV     : aliased struct_timeval;
76
77      Result : Integer;
78      pragma Unreferenced (Result);
79
80   begin
81      --  The return codes for gettimeofday are as follows (from man pages):
82      --    EPERM  settimeofday is called by someone other than the superuser
83      --    EINVAL Timezone (or something else) is invalid
84      --    EFAULT One of tv or tz pointed outside accessible address space
85
86      --  None of these codes signal a potential clock skew, hence the return
87      --  value is never checked.
88
89      Result := gettimeofday (TV'Access, null);
90      return Duration (TV.tv_sec) + Duration (TV.tv_usec) / 10#1#E6;
91   end Clock;
92
93   ---------------------
94   -- Monotonic_Clock --
95   ---------------------
96
97   function Monotonic_Clock return Duration renames Clock;
98
99   -----------------
100   -- To_Timespec --
101   -----------------
102
103   function To_Timespec (D : Duration) return timespec;
104
105   function To_Timespec (D : Duration) return timespec is
106      S : time_t;
107      F : Duration;
108
109   begin
110      S := time_t (Long_Long_Integer (D));
111      F := D - Duration (S);
112
113      --  If F has negative value due to a round-up, adjust for positive F
114      --  value.
115
116      if F < 0.0 then
117         S := S - 1;
118         F := F + 1.0;
119      end if;
120
121      return
122        timespec'(tv_sec  => S,
123                  tv_nsec => Long_Integer (Long_Long_Integer (F * 10#1#E9)));
124   end To_Timespec;
125
126   -----------------
127   -- Timed_Delay --
128   -----------------
129
130   procedure Timed_Delay
131     (Time : Duration;
132      Mode : Integer)
133   is
134      Request    : aliased timespec;
135      Remaind    : aliased timespec;
136      Rel_Time   : Duration;
137      Abs_Time   : Duration;
138      Base_Time  : constant Duration := Clock;
139      Check_Time : Duration := Base_Time;
140
141      Result : Integer;
142      pragma Unreferenced (Result);
143
144   begin
145      if Mode = Relative then
146         Rel_Time := Time;
147         Abs_Time := Time + Check_Time;
148      else
149         Rel_Time := Time - Check_Time;
150         Abs_Time := Time;
151      end if;
152
153      if Rel_Time > 0.0 then
154         loop
155            Request := To_Timespec (Rel_Time);
156            Result := nanosleep (Request'Access, Remaind'Access);
157            Check_Time := Clock;
158
159            exit when Abs_Time <= Check_Time or else Check_Time < Base_Time;
160
161            Rel_Time := Abs_Time - Check_Time;
162         end loop;
163      end if;
164   end Timed_Delay;
165
166   ----------------
167   -- Initialize --
168   ----------------
169
170   procedure Initialize is
171   begin
172      null;
173   end Initialize;
174
175end System.OS_Primitives;
176