1 ------------------------------------------------------------------------------
3 -- GNAT LIBRARY COMPONENTS --
5 -- ADA.CONTAINERS.UNBOUNDED_PRIORITY_QUEUES --
9 -- Copyright (C) 2011-2013, Free Software Foundation, Inc. --
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. --
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. --
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. --
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/>. --
31 -- This unit was originally developed by Matthew J Heaney. --
32 ------------------------------------------------------------------------------
35 with Ada.Containers.Synchronized_Queue_Interfaces;
36 with Ada.Finalization;
39 with package Queue_Interfaces is
40 new Ada.Containers.Synchronized_Queue_Interfaces (<>);
42 type Queue_Priority is private;
44 with function Get_Priority
45 (Element : Queue_Interfaces.Element_Type) return Queue_Priority is <>;
48 (Left, Right : Queue_Priority) return Boolean is <>;
50 Default_Ceiling : System.Any_Priority := System.Priority'Last;
52 package Ada.Containers.Unbounded_Priority_Queues is
55 package Implementation is
57 -- All identifiers in this unit are implementation defined
59 pragma Implementation_Defined;
61 type List_Type is tagged limited private;
64 (List : in out List_Type;
65 New_Item : Queue_Interfaces.Element_Type);
68 (List : in out List_Type;
69 Element : out Queue_Interfaces.Element_Type);
72 (List : in out List_Type;
73 At_Least : Queue_Priority;
74 Element : in out Queue_Interfaces.Element_Type;
75 Success : out Boolean);
77 function Length (List : List_Type) return Count_Type;
79 function Max_Length (List : List_Type) return Count_Type;
84 type Node_Access is access Node_Type;
86 type Node_Type is limited record
87 Element : Queue_Interfaces.Element_Type;
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;
97 overriding procedure Finalize (List : in out List_Type);
101 protected type Queue (Ceiling : System.Any_Priority := Default_Ceiling)
104 is new Queue_Interfaces.Queue with
106 overriding entry Enqueue (New_Item : Queue_Interfaces.Element_Type);
108 overriding entry Dequeue (Element : out Queue_Interfaces.Element_Type);
110 -- The priority queue operation Dequeue_Only_High_Priority had been a
111 -- protected entry in early drafts of AI05-0159, but it was discovered
112 -- that that operation as specified was not in fact implementable. The
113 -- operation was changed from an entry to a protected procedure per the
114 -- ARG meeting in Edinburgh (June 2011), with a different signature and
117 procedure Dequeue_Only_High_Priority
118 (At_Least : Queue_Priority;
119 Element : in out Queue_Interfaces.Element_Type;
120 Success : out Boolean);
122 overriding function Current_Use return Count_Type;
124 overriding function Peak_Use return Count_Type;
127 List : Implementation.List_Type;
130 end Ada.Containers.Unbounded_Priority_Queues;