--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/libgnarl/g-boumai.ads	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,96 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT LIBRARY COMPONENTS                          --
+--                                                                          --
+--                 G N A T . B O U N D E D _ M A I L B O X E S              --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--                     Copyright (C) 2003-2017, AdaCore                     --
+--                                                                          --
+-- GNAT is free software;  you can  redistribute it  and/or modify it under --
+-- terms of the  GNU General Public License as published  by the Free Soft- --
+-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
+-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
+-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
+-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
+--                                                                          --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception,   --
+-- version 3.1, as published by the Free Software Foundation.               --
+--                                                                          --
+-- You should have received a copy of the GNU General Public License and    --
+-- a copy of the GCC Runtime Library Exception along with this program;     --
+-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
+-- <http://www.gnu.org/licenses/>.                                          --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This package provides a thread-safe asynchronous communication facility
+--  in the form of mailboxes. Individual mailbox objects are bounded in size
+--  to a value specified by their Capacity discriminants.
+
+--  Mailboxes actually hold references to messages, not the message values
+--  themselves.
+
+--  Type Mailbox is defined explicitly as a protected type (via derivation
+--  from a protected type) so that clients may treat them accordingly (for
+--  example, by making conditional/timed entry calls).
+
+with System;
+with GNAT.Bounded_Buffers;
+
+generic
+   type Message (<>) is limited private;
+   type Message_Reference is access all Message;
+   --  Mailboxes hold references to Message values, of this type
+
+package GNAT.Bounded_Mailboxes is
+   pragma Preelaborate;
+
+   package Message_Refs is
+      new GNAT.Bounded_Buffers (Message_Reference);
+
+   type Mailbox is new Message_Refs.Bounded_Buffer;
+
+   --  Type Mailbox has two inherited discriminants:
+
+   --  Capacity : Positive;
+   --     Capacity is the maximum number of Message references
+   --     possibly contained at any given instant.
+
+   --  Ceiling : System.Priority;
+   --     Users must specify the ceiling priority for the object.
+   --     If the Real-Time Systems Annex is not in use this value
+   --     is not important.
+
+   --  Protected type Mailbox has the following inherited interface:
+
+   --  entry Insert (Item : Message_Reference);
+   --     Insert Item into the Mailbox. Blocks caller
+   --     until space is available.
+
+   --  entry Remove (Item : out Message_Reference);
+   --     Remove next available Message_Reference from Mailbox.
+   --     Blocks caller until a Message_Reference is available.
+
+   --  function Empty return Boolean;
+   --     Returns whether the Mailbox contains any Message_References.
+   --     Note: State may change immediately after call returns.
+
+   --  function Full return Boolean;
+   --     Returns whether any space remains within the Mailbox.
+   --     Note: State may change immediately after call returns.
+
+   --  function Extent return Natural;
+   --     Returns the number of Message_Reference values currently held
+   --     within the Mailbox.
+   --     Note: State may change immediately after call returns.
+
+   Default_Ceiling : constant System.Priority := Message_Refs.Default_Ceiling;
+   --  A convenience value for the Ceiling discriminant
+
+end GNAT.Bounded_Mailboxes;