gcc/ada/libgnarl/s-osinte__aix.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) 1997-2018, 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 AIX (Native) version of this package
  33
  34 pragma Polling (Off);
  35 --  Turn off polling, we do not want ATC polling to take place during tasking
  36 --  operations. It causes infinite loops and other problems.
  37
  38 package body System.OS_Interface is
  39
  40    use Interfaces.C;
  41
  42    -----------------
  43    -- To_Duration --
  44    -----------------
  45
  46    function To_Duration (TS : timespec) return Duration is
  47    begin
  48       return Duration (TS.tv_sec) + Duration (TS.tv_nsec) / 10#1#E9;
  49    end To_Duration;
  50
  51    ------------------------
  52    -- To_Target_Priority --
  53    ------------------------
  54
  55    function To_Target_Priority
  56      (Prio : System.Any_Priority) return Interfaces.C.int
  57    is
  58       Dispatching_Policy : Character;
  59       pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
  60
  61       Time_Slice_Val : Integer;
  62       pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
  63
  64    begin
  65       --  For the case SCHED_OTHER the only valid priority across all supported
  66       --  versions of AIX is 1 (note that the scheduling policy can be set
  67       --  with the pragma Task_Dispatching_Policy or setting the time slice
  68       --  value). Otherwise, for SCHED_RR and SCHED_FIFO, the system defines
  69       --  priorities in the range 1 .. 127. This means that we must map
  70       --  System.Any_Priority in the range 0 .. 126 to 1 .. 127.
  71
  72       if Dispatching_Policy = ' ' and then Time_Slice_Val < 0 then
  73          return 1;
  74       else
  75          return Interfaces.C.int (Prio) + 1;
  76       end if;
  77    end To_Target_Priority;
  78
  79    -----------------
  80    -- To_Timespec --
  81    -----------------
  82
  83    function To_Timespec (D : Duration) return timespec is
  84       S : time_t;
  85       F : Duration;
  86
  87    begin
  88       S := time_t (Long_Long_Integer (D));
  89       F := D - Duration (S);
  90
  91       --  If F is negative due to a round-up, adjust for positive F value
  92
  93       if F < 0.0 then
  94          S := S - 1;
  95          F := F + 1.0;
  96       end if;
  97
  98       return timespec'(tv_sec => S,
  99                        tv_nsec => long (Long_Long_Integer (F * 10#1#E9)));
 100    end To_Timespec;
 101
 102    -----------------
 103    -- sched_yield --
 104    -----------------
 105
 106    --  AIX Thread does not have sched_yield;
 107
 108    function sched_yield return int is
 109       procedure pthread_yield;
 110       pragma Import (C, pthread_yield, "sched_yield");
 111    begin
 112       pthread_yield;
 113       return 0;
 114    end sched_yield;
 115
 116    --------------------
 117    -- Get_Stack_Base --
 118    --------------------
 119
 120    function Get_Stack_Base (thread : pthread_t) return Address is
 121       pragma Warnings (Off, thread);
 122    begin
 123       return Null_Address;
 124    end Get_Stack_Base;
 125
 126    --------------------------
 127    -- PTHREAD_PRIO_INHERIT --
 128    --------------------------
 129
 130    AIX_Version : Integer := 0;
 131    --  AIX version in the form xy for AIX version x.y (0 means not set)
 132
 133    SYS_NMLN : constant := 32;
 134    --  AIX system constant used to define utsname, see sys/utsname.h
 135
 136    subtype String_NMLN is String (1 .. SYS_NMLN);
 137
 138    type utsname is record
 139       sysname    : String_NMLN;
 140       nodename   : String_NMLN;
 141       release    : String_NMLN;
 142       version    : String_NMLN;
 143       machine    : String_NMLN;
 144       procserial : String_NMLN;
 145    end record;
 146    pragma Convention (C, utsname);
 147
 148    procedure uname (name : out utsname);
 149    pragma Import (C, uname);
 150
 151    function PTHREAD_PRIO_INHERIT return int is
 152       name : utsname;
 153
 154       function Val (C : Character) return Integer;
 155       --  Transform a numeric character ('0' .. '9') to an integer
 156
 157       ---------
 158       -- Val --
 159       ---------
 160
 161       function Val (C : Character) return Integer is
 162       begin
 163          return Character'Pos (C) - Character'Pos ('0');
 164       end Val;
 165
 166    --  Start of processing for PTHREAD_PRIO_INHERIT
 167
 168    begin
 169       if AIX_Version = 0 then
 170
 171          --  Set AIX_Version
 172
 173          uname (name);
 174          AIX_Version := Val (name.version (1)) * 10 + Val (name.release (1));
 175       end if;
 176
 177       if AIX_Version < 53 then
 178
 179          --  Under AIX < 5.3, PTHREAD_PRIO_INHERIT is defined as 0 in pthread.h
 180
 181          return 0;
 182
 183       else
 184          --  Under AIX >= 5.3, PTHREAD_PRIO_INHERIT is defined as 3
 185
 186          return 3;
 187       end if;
 188    end PTHREAD_PRIO_INHERIT;
 189
 190 end System.OS_Interface;