gcc/ada/s-osinte-darwin.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
   4 --                                                                          --
   5 --                   S Y S T E M . O S _ I N T E R F A C E                  --
   6 --                                                                          --
   7 --                                  B o d y                                 --
   8 --                                                                          --
   9 --          Copyright (C) 1999-2015, 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 is a Darwin Threads version of this package
  33
  34 pragma Polling (Off);
  35 --  Turn off polling, we do not want ATC polling to take place during
  36 --  tasking operations. It causes infinite loops and other problems.
  37
  38 with Interfaces.C.Extensions;
  39
  40 package body System.OS_Interface is
  41    use Interfaces.C;
  42    use Interfaces.C.Extensions;
  43
  44    -----------------
  45    -- To_Duration --
  46    -----------------
  47
  48    function To_Duration (TS : timespec) return Duration is
  49    begin
  50       return Duration (TS.tv_sec) + Duration (TS.tv_nsec) / 10#1#E9;
  51    end To_Duration;
  52
  53    ------------------------
  54    -- To_Target_Priority --
  55    ------------------------
  56
  57    function To_Target_Priority
  58      (Prio : System.Any_Priority) return Interfaces.C.int
  59    is
  60    begin
  61       return Interfaces.C.int (Prio);
  62    end To_Target_Priority;
  63
  64    -----------------
  65    -- To_Timespec --
  66    -----------------
  67
  68    function To_Timespec (D : Duration) return timespec is
  69       S : time_t;
  70       F : Duration;
  71
  72    begin
  73       S := time_t (Long_Long_Integer (D));
  74       F := D - Duration (S);
  75
  76       --  If F has negative value due to a round-up, adjust for positive F
  77       --  value.
  78
  79       if F < 0.0 then
  80          S := S - 1;
  81          F := F + 1.0;
  82       end if;
  83
  84       return timespec'(tv_sec => S,
  85         tv_nsec => long (Long_Long_Integer (F * 10#1#E9)));
  86    end To_Timespec;
  87
  88    -------------------
  89    -- clock_gettime --
  90    -------------------
  91
  92    function clock_gettime
  93      (clock_id : clockid_t;
  94       tp       : access timespec) return int
  95    is
  96       pragma Unreferenced (clock_id);
  97
  98       --  Darwin Threads don't have clock_gettime, so use gettimeofday
  99
 100       use Interfaces;
 101
 102       type timeval is array (1 .. 3) of C.long;
 103       --  The timeval array is sized to contain long_long sec and long usec.
 104       --  If long_long'Size = long'Size then it will be overly large but that
 105       --  won't effect the implementation since it's not accessed directly.
 106
 107       procedure timeval_to_duration
 108         (T    : not null access timeval;
 109          sec  : not null access C.Extensions.long_long;
 110          usec : not null access C.long);
 111       pragma Import (C, timeval_to_duration, "__gnat_timeval_to_duration");
 112
 113       Micro  : constant := 10**6;
 114       sec    : aliased C.Extensions.long_long;
 115       usec   : aliased C.long;
 116       TV     : aliased timeval;
 117       Result : int;
 118
 119       function gettimeofday
 120         (Tv : access timeval;
 121          Tz : System.Address := System.Null_Address) return int;
 122       pragma Import (C, gettimeofday, "gettimeofday");
 123
 124    begin
 125       Result := gettimeofday (TV'Access, System.Null_Address);
 126       pragma Assert (Result = 0);
 127       timeval_to_duration (TV'Access, sec'Access, usec'Access);
 128       tp.all := To_Timespec (Duration (sec) + Duration (usec) / Micro);
 129       return Result;
 130    end clock_gettime;
 131
 132    ------------------
 133    -- clock_getres --
 134    ------------------
 135
 136    function clock_getres
 137      (clock_id : clockid_t;
 138       res      : access timespec) return int
 139    is
 140       pragma Unreferenced (clock_id);
 141
 142       --  Darwin Threads don't have clock_getres.
 143
 144       Nano   : constant := 10**9;
 145       nsec   : int := 0;
 146       Result : int := -1;
 147
 148       function clock_get_res return int;
 149       pragma Import (C, clock_get_res, "__gnat_clock_get_res");
 150
 151    begin
 152       nsec := clock_get_res;
 153       res.all := To_Timespec (Duration (0.0) + Duration (nsec) / Nano);
 154
 155       if nsec > 0 then
 156          Result := 0;
 157       end if;
 158
 159       return Result;
 160    end clock_getres;
 161
 162    -----------------
 163    -- sched_yield --
 164    -----------------
 165
 166    function sched_yield return int is
 167       procedure sched_yield_base (arg : System.Address);
 168       pragma Import (C, sched_yield_base, "pthread_yield_np");
 169
 170    begin
 171       sched_yield_base (System.Null_Address);
 172       return 0;
 173    end sched_yield;
 174
 175    ------------------
 176    -- pthread_init --
 177    ------------------
 178
 179    procedure pthread_init is
 180    begin
 181       null;
 182    end pthread_init;
 183
 184    ----------------
 185    -- Stack_Base --
 186    ----------------
 187
 188    function Get_Stack_Base (thread : pthread_t) return Address is
 189       pragma Unreferenced (thread);
 190    begin
 191       return System.Null_Address;
 192    end Get_Stack_Base;
 193
 194 end System.OS_Interface;