gcc/ada/s-intman-vxworks.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                 GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS                 --
   4 --                                                                          --
   5 --            S Y S T E M . I N T E R R U P T _ M A N A G E M E N T         --
   6 --                                                                          --
   7 --                                  S p e c                                 --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2009, 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 the VxWorks version of this package
  33
  34 --  This package encapsulates and centralizes information about all
  35 --  uses of interrupts (or signals), including the target-dependent
  36 --  mapping of interrupts (or signals) to exceptions.
  37
  38 --  Unlike the original design, System.Interrupt_Management can only
  39 --  be used for tasking systems.
  40
  41 --  PLEASE DO NOT put any subprogram declarations with arguments of
  42 --  type Interrupt_ID into the visible part of this package. The type
  43 --  Interrupt_ID is used to derive the type in Ada.Interrupts, and
  44 --  adding more operations to that type would be illegal according
  45 --  to the Ada Reference Manual. This is the reason why the signals
  46 --  sets are implemented using visible arrays rather than functions.
  47
  48 with System.OS_Interface;
  49
  50 with Interfaces.C;
  51
  52 package System.Interrupt_Management is
  53    pragma Preelaborate;
  54
  55    type Interrupt_Mask is limited private;
  56
  57    type Interrupt_ID is new Interfaces.C.int
  58      range 0 .. System.OS_Interface.Max_Interrupt;
  59
  60    type Interrupt_Set is array (Interrupt_ID) of Boolean;
  61
  62    subtype Signal_ID is Interrupt_ID
  63      range 0 .. Interfaces.C."-" (System.OS_Interface.NSIG, 1);
  64
  65    type Signal_Set is array (Signal_ID) of Boolean;
  66
  67    --  The following objects serve as constants, but are initialized in the
  68    --  body to aid portability. This permits us to use more portable names for
  69    --  interrupts, where distinct names may map to the same interrupt ID
  70    --  value.
  71
  72    --  For example, suppose SIGRARE is a signal that is not defined on all
  73    --  systems, but is always reserved when it is defined. If we have the
  74    --  convention that ID zero is not used for any "real" signals, and SIGRARE
  75    --  = 0 when SIGRARE is not one of the locally supported signals, we can
  76    --  write:
  77    --     Reserved (SIGRARE) := true;
  78    --  and the initialization code will be portable.
  79
  80    Abort_Task_Interrupt : Signal_ID;
  81    --  The signal that is used to implement task abort if an interrupt is used
  82    --  for that purpose. This is one of the reserved signals.
  83
  84    Keep_Unmasked : Signal_Set := (others => False);
  85    --  Keep_Unmasked (I) is true iff the signal I is one that must that must
  86    --  be kept unmasked at all times, except (perhaps) for short critical
  87    --  sections. This includes signals that are mapped to exceptions, but may
  88    --  also include interrupts (e.g. timer) that need to be kept unmasked for
  89    --  other reasons. Where signal masking is per-task, the signal should be
  90    --  unmasked in ALL TASKS.
  91
  92    Reserve : Interrupt_Set := (others => False);
  93    --  Reserve (I) is true iff the interrupt I is one that cannot be permitted
  94    --  to be attached to a user handler. The possible reasons are many. For
  95    --  example, it may be mapped to an exception used to implement task abort,
  96    --  or used to implement time delays.
  97
  98    procedure Initialize_Interrupts;
  99    --  Under VxWorks, there is no signal inheritance between tasks.
 100    --  This procedure is used to initialize signal-to-exception mapping in
 101    --  each task.
 102
 103    procedure Initialize;
 104    --  Initialize the various variables defined in this package. This procedure
 105    --  must be called before accessing any object from this package and can be
 106    --  called multiple times (only the first call has any effect).
 107
 108 private
 109    type Interrupt_Mask is new System.OS_Interface.sigset_t;
 110    --  In some implementation Interrupt_Mask can be represented as a linked
 111    --  list.
 112
 113 end System.Interrupt_Management;