gcc/ada/s-osinte-vxworks.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) 1997-2007, 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 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,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  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.                                      --
  28 --                                                                          --
  29 -- GNARL was developed by the GNARL team at Florida State University.       --
  30 -- Extensive contributions were provided by Ada Core Technologies, Inc.     --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  This is the VxWorks version
  35
  36 --  This package encapsulates all direct interfaces to OS services that are
  37 --  needed by children of System.
  38
  39 pragma Polling (Off);
  40 --  Turn off polling, we do not want ATC polling to take place during tasking
  41 --  operations. It causes infinite loops and other problems.
  42
  43 package body System.OS_Interface is
  44
  45    use type Interfaces.C.int;
  46
  47    Low_Priority : constant := 255;
  48    --  VxWorks native (default) lowest scheduling priority
  49
  50    ----------
  51    -- kill --
  52    ----------
  53
  54    function kill (pid : t_id; sig : Signal) return int is
  55    begin
  56       return System.VxWorks.Ext.kill (pid, int (sig));
  57    end kill;
  58
  59    -------------
  60    -- sigwait --
  61    -------------
  62
  63    function sigwait
  64      (set : access sigset_t;
  65       sig : access Signal) return int
  66    is
  67       Result : int;
  68
  69       function sigwaitinfo
  70         (set : access sigset_t; sigvalue : System.Address) return int;
  71       pragma Import (C, sigwaitinfo, "sigwaitinfo");
  72
  73    begin
  74       Result := sigwaitinfo (set, System.Null_Address);
  75
  76       if Result /= -1 then
  77          sig.all := Signal (Result);
  78          return 0;
  79       else
  80          sig.all := 0;
  81          return errno;
  82       end if;
  83    end sigwait;
  84
  85    -----------------
  86    -- To_Duration --
  87    -----------------
  88
  89    function To_Duration (TS : timespec) return Duration is
  90    begin
  91       return Duration (TS.ts_sec) + Duration (TS.ts_nsec) / 10#1#E9;
  92    end To_Duration;
  93
  94    -----------------
  95    -- To_Timespec --
  96    -----------------
  97
  98    function To_Timespec (D : Duration) return timespec is
  99       S : time_t;
 100       F : Duration;
 101
 102    begin
 103       S := time_t (Long_Long_Integer (D));
 104       F := D - Duration (S);
 105
 106       --  If F is negative due to a round-up, adjust for positive F value
 107
 108       if F < 0.0 then
 109          S := S - 1;
 110          F := F + 1.0;
 111       end if;
 112
 113       return timespec'(ts_sec  => S,
 114                        ts_nsec => long (Long_Long_Integer (F * 10#1#E9)));
 115    end To_Timespec;
 116
 117    -------------------------
 118    -- To_VxWorks_Priority --
 119    -------------------------
 120
 121    function To_VxWorks_Priority (Priority : int) return int is
 122    begin
 123       return Low_Priority - Priority;
 124    end To_VxWorks_Priority;
 125
 126    --------------------
 127    -- To_Clock_Ticks --
 128    --------------------
 129
 130    --  ??? - For now, we'll always get the system clock rate since it is
 131    --  allowed to be changed during run-time in VxWorks. A better method would
 132    --  be to provide an operation to set it that so we can always know its
 133    --  value.
 134
 135    --  Another thing we should probably allow for is a resultant tick count
 136    --  greater than int'Last. This should probably be a procedure with two
 137    --  output parameters, one in the range 0 .. int'Last, and another
 138    --  representing the overflow count.
 139
 140    function To_Clock_Ticks (D : Duration) return int is
 141       Ticks          : Long_Long_Integer;
 142       Rate_Duration  : Duration;
 143       Ticks_Duration : Duration;
 144
 145    begin
 146       if D < 0.0 then
 147          return -1;
 148       end if;
 149
 150       --  Ensure that the duration can be converted to ticks
 151       --  at the current clock tick rate without overflowing.
 152
 153       Rate_Duration := Duration (sysClkRateGet);
 154
 155       if D > (Duration'Last / Rate_Duration) then
 156          Ticks := Long_Long_Integer (int'Last);
 157       else
 158          Ticks_Duration := D * Rate_Duration;
 159          Ticks := Long_Long_Integer (Ticks_Duration);
 160
 161          if Ticks_Duration > Duration (Ticks) then
 162             Ticks := Ticks + 1;
 163          end if;
 164
 165          if Ticks > Long_Long_Integer (int'Last) then
 166             Ticks := Long_Long_Integer (int'Last);
 167          end if;
 168       end if;
 169
 170       return int (Ticks);
 171    end To_Clock_Ticks;
 172
 173 end System.OS_Interface;