1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT LIBRARY COMPONENTS                          --
4--                                                                          --
5--             ADA.CONTAINERS.RED_BLACK_TREES.GENERIC_OPERATIONS            --
6--                                                                          --
7--                                 S p e c                                  --
8--                                                                          --
9--          Copyright (C) 2004-2009, Free Software Foundation, Inc.         --
10--                                                                          --
11-- GNAT 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-- This unit was originally developed by Matthew J Heaney.                  --
28------------------------------------------------------------------------------
29
30--  Tree_Type is used to implement the ordered containers. This package
31--  declares the tree operations that do not depend on keys.
32
33with Ada.Streams; use Ada.Streams;
34
35generic
36   with package Tree_Types is new Generic_Tree_Types (<>);
37   use Tree_Types;
38
39   with function  Parent (Node : Node_Access) return Node_Access is <>;
40   with procedure Set_Parent (Node : Node_Access; Parent : Node_Access) is <>;
41   with function  Left (Node : Node_Access) return Node_Access is <>;
42   with procedure Set_Left (Node : Node_Access; Left : Node_Access) is <>;
43   with function  Right (Node : Node_Access) return Node_Access is <>;
44   with procedure Set_Right (Node : Node_Access; Right : Node_Access) is <>;
45   with function  Color (Node : Node_Access) return Color_Type is <>;
46   with procedure Set_Color (Node : Node_Access; Color : Color_Type) is <>;
47
48package Ada.Containers.Red_Black_Trees.Generic_Operations is
49   pragma Pure;
50
51   function Min (Node : Node_Access) return Node_Access;
52   --  Returns the smallest-valued node of the subtree rooted at Node
53
54   function Max (Node : Node_Access) return Node_Access;
55   --  Returns the largest-valued node of the subtree rooted at Node
56
57   --  NOTE: The Check_Invariant operation was used during early
58   --  development of the red-black tree. Now that the tree type
59   --  implementation has matured, we don't really need Check_Invariant
60   --  anymore.
61
62   --  procedure Check_Invariant (Tree : Tree_Type);
63
64   function Vet (Tree : Tree_Type; Node : Node_Access) return Boolean;
65   --  Inspects Node to determine (to the extent possible) whether
66   --  the node is valid; used to detect if the node is dangling.
67
68   function Next (Node : Node_Access) return Node_Access;
69   --  Returns the smallest node greater than Node
70
71   function Previous (Node : Node_Access) return Node_Access;
72   --  Returns the largest node less than Node
73
74   generic
75      with function Is_Equal (L, R : Node_Access) return Boolean;
76   function Generic_Equal (Left, Right : Tree_Type) return Boolean;
77   --  Uses Is_Equal to perform a node-by-node comparison of the
78   --  Left and Right trees; processing stops as soon as the first
79   --  non-equal node is found.
80
81   procedure Delete_Node_Sans_Free
82     (Tree : in out Tree_Type;
83      Node : Node_Access);
84   --  Removes Node from Tree without deallocating the node. If Tree
85   --  is busy then Program_Error is raised.
86
87   generic
88      with procedure Free (X : in out Node_Access);
89   procedure Generic_Delete_Tree (X : in out Node_Access);
90   --  Deallocates the tree rooted at X, calling Free on each node
91
92   generic
93      with function Copy_Node (Source : Node_Access) return Node_Access;
94      with procedure Delete_Tree (X : in out Node_Access);
95   function Generic_Copy_Tree (Source_Root : Node_Access) return Node_Access;
96   --  Copies the tree rooted at Source_Root, using Copy_Node to copy each
97   --  node of the source tree. If Copy_Node propagates an exception
98   --  (e.g. Storage_Error), then Delete_Tree is first used to deallocate
99   --  the target tree, and then the exception is propagated.
100
101   generic
102      with function Copy_Tree (Root : Node_Access) return Node_Access;
103   procedure Generic_Adjust (Tree : in out Tree_Type);
104   --  Used to implement controlled Adjust. On input to Generic_Adjust, Tree
105   --  holds a bitwise (shallow) copy of the source tree (as would be the case
106   --  when controlled Adjust is called). On output, Tree holds its own (deep)
107   --  copy of the source tree, which is constructed by calling Copy_Tree.
108
109   generic
110      with procedure Delete_Tree (X : in out Node_Access);
111   procedure Generic_Clear (Tree : in out Tree_Type);
112   --  Clears Tree by deallocating all of its nodes. If Tree is busy then
113   --  Program_Error is raised.
114
115   generic
116      with procedure Clear (Tree : in out Tree_Type);
117   procedure Generic_Move (Target, Source : in out Tree_Type);
118   --  Moves the tree belonging to Source onto Target. If Source is busy then
119   --  Program_Error is raised. Otherwise Target is first cleared (by calling
120   --  Clear, to deallocate its existing tree), then given the Source tree, and
121   --  then finally Source is cleared (by setting its pointers to null).
122
123   generic
124      with procedure Process (Node : Node_Access) is <>;
125   procedure Generic_Iteration (Tree : Tree_Type);
126   --  Calls Process for each node in Tree, in order from smallest-valued
127   --  node to largest-valued node.
128
129   generic
130      with procedure Process (Node : Node_Access) is <>;
131   procedure Generic_Reverse_Iteration (Tree : Tree_Type);
132   --  Calls Process for each node in Tree, in order from largest-valued
133   --  node to smallest-valued node.
134
135   generic
136      with procedure Write_Node
137        (Stream : not null access Root_Stream_Type'Class;
138         Node   : Node_Access);
139   procedure Generic_Write
140     (Stream : not null access Root_Stream_Type'Class;
141      Tree   : Tree_Type);
142   --  Used to implement stream attribute T'Write. Generic_Write
143   --  first writes the number of nodes into Stream, then calls
144   --  Write_Node for each node in Tree.
145
146   generic
147      with procedure Clear (Tree : in out Tree_Type);
148      with function Read_Node
149        (Stream : not null access Root_Stream_Type'Class) return Node_Access;
150   procedure Generic_Read
151     (Stream : not null access Root_Stream_Type'Class;
152      Tree   : in out Tree_Type);
153   --  Used to implement stream attribute T'Read. Generic_Read
154   --  first clears Tree. It then reads the number of nodes out of
155   --  Stream, and calls Read_Node for each node in Stream.
156
157   procedure Rebalance_For_Insert
158     (Tree : in out Tree_Type;
159      Node : Node_Access);
160   --  This rebalances Tree to complete the insertion of Node (which
161   --  must already be linked in at its proper insertion position).
162
163end Ada.Containers.Red_Black_Trees.Generic_Operations;
164