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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT LIBRARY COMPONENTS --
4 -- --
5 -- ADA.CONTAINERS.HASH_TABLES.GENERIC_BOUNDED_OPERATIONS --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 2004-2015, 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 -- --
19 -- --
20 -- --
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 -- Hash_Table_Type is used to implement hashed containers. This package
31 -- declares hash-table operations that do not depend on keys.
32
33 with Ada.Streams;
34
35 generic
36 with package HT_Types is
37 new Generic_Bounded_Hash_Table_Types (<>);
38
39 use HT_Types, HT_Types.Implementation;
40
41 with function Hash_Node (Node : Node_Type) return Hash_Type;
42
43 with function Next (Node : Node_Type) return Count_Type;
44
45 with procedure Set_Next
46 (Node : in out Node_Type;
47 Next : Count_Type);
48
49 package Ada.Containers.Hash_Tables.Generic_Bounded_Operations is
50 pragma Pure;
51
52 function Index
53 (Buckets : Buckets_Type;
54 Node : Node_Type) return Hash_Type;
55 pragma Inline (Index);
56 -- Uses the hash value of Node to compute its Buckets array index
57
58 function Index
59 (HT : Hash_Table_Type'Class;
60 Node : Node_Type) return Hash_Type;
61 pragma Inline (Index);
62 -- Uses the hash value of Node to compute its Hash_Table buckets array
63 -- index.
64
65 function Checked_Index
66 (Hash_Table : aliased in out Hash_Table_Type'Class;
67 Node : Count_Type) return Hash_Type;
68 -- Calls Index, but also locks and unlocks the container, per AI05-0022, in
69 -- order to detect element tampering by the generic actual Hash function.
70
71 generic
72 with function Find
73 (HT : Hash_Table_Type'Class;
74 Key : Node_Type) return Boolean;
75 function Generic_Equal (L, R : Hash_Table_Type'Class) return Boolean;
76 -- Used to implement hashed container equality. For each node in hash table
77 -- L, it calls Find to search for an equivalent item in hash table R. If
78 -- Find returns False for any node then Generic_Equal terminates
79 -- immediately and returns False. Otherwise if Find returns True for every
80 -- node then Generic_Equal returns True.
81
82 procedure Clear (HT : in out Hash_Table_Type'Class);
83 -- Deallocates each node in hash table HT. (Note that it only deallocates
84 -- the nodes, not the buckets array.) Program_Error is raised if the hash
85 -- table is busy.
86
87 procedure Delete_Node_At_Index
88 (HT : in out Hash_Table_Type'Class;
89 Indx : Hash_Type;
90 X : Count_Type);
91 -- Delete a node whose bucket position is known. extracted from following
92 -- subprogram, but also used directly to remove a node whose element has
93 -- been modified through a key_preserving reference: in that case we cannot
94 -- use the value of the element precisely because the current value does
95 -- not correspond to the hash code that determines its bucket.
96
97 procedure Delete_Node_Sans_Free
98 (HT : in out Hash_Table_Type'Class;
99 X : Count_Type);
100 -- Removes node X from the hash table without deallocating the node
101
102 generic
103 with procedure Set_Element (Node : in out Node_Type);
104 procedure Generic_Allocate
105 (HT : in out Hash_Table_Type'Class;
106 Node : out Count_Type);
107 -- Claim a node from the free store. Generic_Allocate first
108 -- calls Set_Element on the potential node, and then returns
109 -- the node's index as the value of the Node parameter.
110
111 procedure Free
112 (HT : in out Hash_Table_Type'Class;
113 X : Count_Type);
114 -- Return a node back to the free store, from where it had
115 -- been previously claimed via Generic_Allocate.
116
117 function First (HT : Hash_Table_Type'Class) return Count_Type;
118 -- Returns the head of the list in the first (lowest-index) non-empty
119 -- bucket.
120
121 function Next
122 (HT : Hash_Table_Type'Class;
123 Node : Count_Type) return Count_Type;
124 -- Returns the node that immediately follows Node. This corresponds to
125 -- either the next node in the same bucket, or (if Node is the last node in
126 -- its bucket) the head of the list in the first non-empty bucket that
127 -- follows.
128
129 generic
130 with procedure Process (Node : Count_Type);
131 procedure Generic_Iteration (HT : Hash_Table_Type'Class);
132 -- Calls Process for each node in hash table HT
133
134 generic
135 use Ada.Streams;
136 with procedure Write
137 (Stream : not null access Root_Stream_Type'Class;
138 Node : Node_Type);
139 procedure Generic_Write
140 (Stream : not null access Root_Stream_Type'Class;
141 HT : Hash_Table_Type'Class);
142 -- Used to implement the streaming attribute for hashed containers. It
143 -- calls Write for each node to write its value into Stream.
144
145 generic
146 use Ada.Streams;
147 with function New_Node (Stream : not null access Root_Stream_Type'Class)
148 return Count_Type;
149 procedure Generic_Read
150 (Stream : not null access Root_Stream_Type'Class;
151 HT : out Hash_Table_Type'Class);
152 -- Used to implement the streaming attribute for hashed containers. It
153 -- first clears hash table HT, then populates the hash table by calling
154 -- New_Node for each item in Stream.
155
156 end Ada.Containers.Hash_Tables.Generic_Bounded_Operations;