1------------------------------------------------------------------------------ 2-- -- 3-- GNAT LIBRARY COMPONENTS -- 4-- -- 5-- ADA.CONTAINERS.UNBOUNDED_PRIORITY_QUEUES -- 6-- -- 7-- S p e c -- 8-- -- 9-- Copyright (C) 2011, Free Software Foundation, Inc. -- 10-- -- 11-- This specification is derived from the Ada Reference Manual for use with -- 12-- GNAT. The copyright notice above, and the license provisions that follow -- 13-- apply solely to the contents of the part following the private keyword. -- 14-- -- 15-- GNAT is free software; you can redistribute it and/or modify it under -- 16-- terms of the GNU General Public License as published by the Free Soft- -- 17-- ware Foundation; either version 3, or (at your option) any later ver- -- 18-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 19-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 20-- or FITNESS FOR A PARTICULAR PURPOSE. -- 21-- -- 22-- As a special exception under Section 7 of GPL version 3, you are granted -- 23-- additional permissions described in the GCC Runtime Library Exception, -- 24-- version 3.1, as published by the Free Software Foundation. -- 25-- -- 26-- You should have received a copy of the GNU General Public License and -- 27-- a copy of the GCC Runtime Library Exception along with this program; -- 28-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- 29-- <http://www.gnu.org/licenses/>. -- 30-- -- 31-- This unit was originally developed by Matthew J Heaney. -- 32------------------------------------------------------------------------------ 33 34with System; 35with Ada.Containers.Synchronized_Queue_Interfaces; 36with Ada.Finalization; 37 38generic 39 with package Queue_Interfaces is 40 new Ada.Containers.Synchronized_Queue_Interfaces (<>); 41 42 type Queue_Priority is private; 43 44 with function Get_Priority 45 (Element : Queue_Interfaces.Element_Type) return Queue_Priority is <>; 46 47 with function Before 48 (Left, Right : Queue_Priority) return Boolean is <>; 49 50 Default_Ceiling : System.Any_Priority := System.Priority'Last; 51 52package Ada.Containers.Unbounded_Priority_Queues is 53 pragma Preelaborate; 54 55 package Implementation is 56 57 -- All identifiers in this unit are implementation defined 58 59 pragma Implementation_Defined; 60 61 type List_Type is tagged limited private; 62 63 procedure Enqueue 64 (List : in out List_Type; 65 New_Item : Queue_Interfaces.Element_Type); 66 67 procedure Dequeue 68 (List : in out List_Type; 69 Element : out Queue_Interfaces.Element_Type); 70 71 procedure Dequeue 72 (List : in out List_Type; 73 At_Least : Queue_Priority; 74 Element : in out Queue_Interfaces.Element_Type; 75 Success : out Boolean); 76 77 function Length (List : List_Type) return Count_Type; 78 79 function Max_Length (List : List_Type) return Count_Type; 80 81 private 82 83 type Node_Type; 84 type Node_Access is access Node_Type; 85 86 type Node_Type is limited record 87 Element : Queue_Interfaces.Element_Type; 88 Next : Node_Access; 89 end record; 90 91 type List_Type is new Ada.Finalization.Limited_Controlled with record 92 First, Last : Node_Access; 93 Length : Count_Type := 0; 94 Max_Length : Count_Type := 0; 95 end record; 96 97 overriding 98 procedure Finalize (List : in out List_Type); 99 100 end Implementation; 101 102 protected type Queue (Ceiling : System.Any_Priority := Default_Ceiling) 103 with Priority => Ceiling is new Queue_Interfaces.Queue with 104 105 overriding 106 entry Enqueue (New_Item : Queue_Interfaces.Element_Type); 107 108 overriding 109 entry Dequeue (Element : out Queue_Interfaces.Element_Type); 110 111 -- The priority queue operation Dequeue_Only_High_Priority had been a 112 -- protected entry in early drafts of AI05-0159, but it was discovered 113 -- that that operation as specified was not in fact implementable. The 114 -- operation was changed from an entry to a protected procedure per the 115 -- ARG meeting in Edinburgh (June 2011), with a different signature and 116 -- semantics. 117 118 not overriding 119 procedure Dequeue_Only_High_Priority 120 (At_Least : Queue_Priority; 121 Element : in out Queue_Interfaces.Element_Type; 122 Success : out Boolean); 123 124 overriding 125 function Current_Use return Count_Type; 126 127 overriding 128 function Peak_Use return Count_Type; 129 130 private 131 132 List : Implementation.List_Type; 133 134 end Queue; 135 136end Ada.Containers.Unbounded_Priority_Queues; 137