gcc/ada/s-tasren.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS               --
   4 --                                                                          --
   5 --             S Y S T E M . T A S K I N G . R E N D E Z V O U S            --
   6 --                                                                          --
   7 --                                  S p e c                                 --
   8 --                                                                          --
   9 --                             $Revision: 1.26 $                            --
  10 --                                                                          --
  11 --          Copyright (C) 1992-1998, Free Software Foundation, Inc.         --
  12 --                                                                          --
  13 -- GNARL is free software; you can  redistribute it  and/or modify it under --
  14 -- terms of the  GNU General Public License as published  by the Free Soft- --
  15 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  16 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
  17 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  18 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  19 -- for  more details.  You should have  received  a copy of the GNU General --
  20 -- Public License  distributed with GNARL; see file COPYING.  If not, write --
  21 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  22 -- MA 02111-1307, USA.                                                      --
  23 --                                                                          --
  24 -- As a special exception,  if other files  instantiate  generics from this --
  25 -- unit, or you link  this unit with other files  to produce an executable, --
  26 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  27 -- covered  by the  GNU  General  Public  License.  This exception does not --
  28 -- however invalidate  any other reasons why  the executable file  might be --
  29 -- covered by the  GNU Public License.                                      --
  30 --                                                                          --
  31 -- GNARL was developed by the GNARL team at Florida State University. It is --
  32 -- now maintained by Ada Core Technologies Inc. in cooperation with Florida --
  33 -- State University (http://www.gnat.com).                                  --
  34 --                                                                          --
  35 ------------------------------------------------------------------------------
  36
  37 --  Note: the compiler generates direct calls to this interface, via Rtsfind.
  38 --  Any changes to this interface may require corresponding compiler changes.
  39
  40 with Ada.Exceptions;
  41 --  Used for, Exception_Id
  42
  43 with System.Tasking.Protected_Objects.Entries;
  44 --  used for Protection_Entries
  45
  46 package System.Tasking.Rendezvous is
  47    --  This interface is described in the document
  48    --  Gnu Ada Runtime Library Interface (GNARLI).
  49
  50    package STPE renames System.Tasking.Protected_Objects.Entries;
  51
  52    procedure Task_Entry_Call
  53      (Acceptor              : Task_ID;
  54       E                     : Task_Entry_Index;
  55       Uninterpreted_Data    : System.Address;
  56       Mode                  : Call_Modes;
  57       Rendezvous_Successful : out Boolean);
  58    --  General entry call
  59
  60    procedure Timed_Task_Entry_Call
  61      (Acceptor              : Task_ID;
  62       E                     : Task_Entry_Index;
  63       Uninterpreted_Data    : System.Address;
  64       Timeout               : Duration;
  65       Mode                  : Delay_Modes;
  66       Rendezvous_Successful : out Boolean);
  67    --  Timed entry call without using ATC.
  68
  69    procedure Call_Simple
  70      (Acceptor           : Task_ID;
  71       E                  : Task_Entry_Index;
  72       Uninterpreted_Data : System.Address);
  73    --  Simple entry call
  74
  75    procedure Cancel_Task_Entry_Call (Cancelled : out Boolean);
  76    --  Cancel pending task entry call
  77
  78    procedure Requeue_Task_Entry
  79      (Acceptor   : Task_ID;
  80       E          : Task_Entry_Index;
  81       With_Abort : Boolean);
  82
  83    procedure Requeue_Protected_To_Task_Entry
  84      (Object     : STPE.Protection_Entries_Access;
  85       Acceptor   : Task_ID;
  86       E          : Task_Entry_Index;
  87       With_Abort : Boolean);
  88
  89    procedure Selective_Wait
  90      (Open_Accepts       : Accept_List_Access;
  91       Select_Mode        : Select_Modes;
  92       Uninterpreted_Data : out System.Address;
  93       Index              : out Select_Index);
  94    --  Selective wait
  95
  96    procedure Timed_Selective_Wait
  97      (Open_Accepts       : Accept_List_Access;
  98       Select_Mode        : Select_Modes;
  99       Uninterpreted_Data : out System.Address;
 100       Timeout            : Duration;
 101       Mode               : Delay_Modes;
 102       Index              : out Select_Index);
 103    --  Selective wait with timeout without using ATC.
 104
 105    procedure Accept_Call
 106      (E                  : Task_Entry_Index;
 107       Uninterpreted_Data : out System.Address);
 108    --  Accept an entry call
 109
 110    procedure Accept_Trivial (E : Task_Entry_Index);
 111    --  Accept an entry call that has no parameters and no body
 112
 113    function Task_Count (E : Task_Entry_Index) return Natural;
 114    --  Return number of tasks waiting on the entry E (of current task)
 115
 116    function Callable (T : Task_ID) return Boolean;
 117    --  Return T'CALLABLE
 118
 119    type Task_Entry_Nesting_Depth is new Task_Entry_Index
 120      range 0 .. Max_Task_Entry;
 121
 122    function Task_Entry_Caller (D : Task_Entry_Nesting_Depth) return Task_ID;
 123    --  Return E'Caller.  This will only work if called from within an
 124    --  accept statement that is handling E, as required by the
 125    --  LRM (C.7.1(14)).
 126
 127    procedure Complete_Rendezvous;
 128    --  Called by acceptor to wake up caller
 129
 130    procedure Exceptional_Complete_Rendezvous
 131      (Ex : Ada.Exceptions.Exception_Id);
 132    --  Called by acceptor to mark the end of the current rendezvous and
 133    --  propagate an exception to the caller.
 134
 135    --  For internal use only:
 136
 137    function Task_Do_Or_Queue
 138      (Self_ID    : Task_ID;
 139       Entry_Call : Entry_Call_Link;
 140       With_Abort : Boolean) return Boolean;
 141    --  Call this only with abort deferred and holding lock of Acceptor.
 142    --  Returns False iff the call cannot be served or queued, as is the
 143    --  case if the caller is not callable; i.e., a False return value
 144    --  indicates that Tasking_Error should be raised.
 145    --  Either initiate the entry call, such that the accepting task is
 146    --  free to execute the rendezvous, queue the call on the acceptor's
 147    --  queue, or cancel the call.  Conditional calls that cannot be
 148    --  accepted immediately are cancelled.
 149
 150 end System.Tasking.Rendezvous;