| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT LIBRARY COMPONENTS -- |
| -- -- |
| -- ADA.CONTAINERS.HASH_TABLES.GENERIC_OPERATIONS -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 2004-2023, Free Software Foundation, Inc. -- |
| -- -- |
| -- 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/>. -- |
| -- -- |
| -- This unit was originally developed by Matthew J Heaney. -- |
| ------------------------------------------------------------------------------ |
| |
| -- Hash_Table_Type is used to implement hashed containers. This package |
| -- declares hash-table operations that do not depend on keys. |
| |
| with Ada.Streams; |
| |
| generic |
| |
| with package HT_Types is |
| new Generic_Hash_Table_Types (<>); |
| |
| use HT_Types, HT_Types.Implementation; |
| |
| with function Hash_Node (Node : Node_Access) return Hash_Type; |
| |
| with function Next (Node : Node_Access) return Node_Access; |
| |
| with procedure Set_Next |
| (Node : Node_Access; |
| Next : Node_Access); |
| |
| with function Copy_Node (Source : Node_Access) return Node_Access; |
| |
| with procedure Free (X : in out Node_Access); |
| |
| package Ada.Containers.Hash_Tables.Generic_Operations is |
| pragma Preelaborate; |
| |
| procedure Free_Hash_Table (Buckets : in out Buckets_Access); |
| -- First frees the nodes in all non-null buckets of Buckets, and then frees |
| -- the Buckets array itself. |
| |
| function Index |
| (Buckets : Buckets_Type; |
| Node : Node_Access) return Hash_Type; |
| pragma Inline (Index); |
| -- Uses the hash value of Node to compute its Buckets array index |
| |
| function Index |
| (Hash_Table : Hash_Table_Type; |
| Node : Node_Access) return Hash_Type; |
| pragma Inline (Index); |
| -- Uses the hash value of Node to compute its Hash_Table buckets array |
| -- index. |
| |
| function Checked_Index |
| (Hash_Table : aliased in out Hash_Table_Type; |
| Buckets : Buckets_Type; |
| Node : Node_Access) return Hash_Type; |
| -- Calls Index, but also locks and unlocks the container, per AI05-0022, in |
| -- order to detect element tampering by the generic actual Hash function. |
| |
| function Checked_Index |
| (Hash_Table : aliased in out Hash_Table_Type; |
| Node : Node_Access) return Hash_Type; |
| -- Calls Checked_Index using Hash_Table's buckets array. |
| |
| procedure Adjust (HT : in out Hash_Table_Type); |
| -- Used to implement controlled Adjust. It is assumed that HT has the value |
| -- of the bit-wise copy that immediately follows controlled Finalize. |
| -- Adjust first allocates a new buckets array for HT (having the same |
| -- length as the source), and then allocates a copy of each node of source. |
| |
| procedure Finalize (HT : in out Hash_Table_Type); |
| -- Used to implement controlled Finalize. It first calls Clear to |
| -- deallocate any remaining nodes, and then deallocates the buckets array. |
| |
| generic |
| with function Find |
| (HT : Hash_Table_Type; |
| Key : Node_Access) return Boolean; |
| function Generic_Equal |
| (L, R : Hash_Table_Type) return Boolean; |
| -- Used to implement hashed container equality. For each node in hash table |
| -- L, it calls Find to search for an equivalent item in hash table R. If |
| -- Find returns False for any node then Generic_Equal terminates |
| -- immediately and returns False. Otherwise if Find returns True for every |
| -- node then Generic_Equal returns True. |
| |
| procedure Clear (HT : in out Hash_Table_Type); |
| -- Deallocates each node in hash table HT. (Note that it only deallocates |
| -- the nodes, not the buckets array. Also note that for bounded containers, |
| -- the buckets array is not dynamically allocated). Program_Error is raised |
| -- if the hash table is busy. |
| |
| procedure Move (Target, Source : in out Hash_Table_Type); |
| -- Moves (not copies) the buckets array and nodes from Source to |
| -- Target. Program_Error is raised if Source is busy. The Target is first |
| -- cleared to deallocate its nodes (implying that Program_Error is also |
| -- raised if Target is busy). Source is empty following the move. |
| |
| function Capacity (HT : Hash_Table_Type) return Count_Type; |
| -- Returns the length of the buckets array |
| |
| procedure Reserve_Capacity |
| (HT : in out Hash_Table_Type; |
| N : Count_Type); |
| -- If N is greater than the current capacity, then it expands the buckets |
| -- array to at least the value N. If N is less than the current capacity, |
| -- then it contracts the buckets array. In either case existing nodes are |
| -- rehashed onto the new buckets array, and the old buckets array is |
| -- deallocated. Program_Error is raised if the hash table is busy. |
| |
| procedure Delete_Node_At_Index |
| (HT : in out Hash_Table_Type; |
| Indx : Hash_Type; |
| X : in out Node_Access); |
| -- Delete a node whose bucket position is known. Used to remove a node |
| -- whose element has been modified through a key_preserving reference. |
| -- We cannot use the value of the element precisely because the current |
| -- value does not correspond to the hash code that determines the bucket. |
| |
| procedure Delete_Node_Sans_Free |
| (HT : in out Hash_Table_Type; |
| X : Node_Access); |
| -- Removes node X from the hash table without deallocating the node |
| |
| function First |
| (HT : Hash_Table_Type) return Node_Access; |
| function First |
| (HT : Hash_Table_Type; |
| Position : out Hash_Type) return Node_Access; |
| -- Returns the head of the list in the first (lowest-index) non-empty |
| -- bucket. Position will be the index of the bucket of the first node. |
| -- It is provided so that clients can implement efficient iterators. |
| |
| function Next |
| (HT : aliased in out Hash_Table_Type; |
| Node : Node_Access) return Node_Access; |
| function Next |
| (HT : aliased in out Hash_Table_Type; |
| Node : Node_Access; |
| Position : in out Hash_Type) return Node_Access; |
| -- Returns the node that immediately follows Node. This corresponds to |
| -- either the next node in the same bucket, or (if Node is the last node in |
| -- its bucket) the head of the list in the first non-empty bucket that |
| -- follows. |
| -- |
| -- If Node_Position is supplied, then it will be used as a starting point |
| -- for iteration (Node_Position must be the index of Node's buckets). If it |
| -- is not supplied, it will be recomputed. It is provided so that clients |
| -- can implement efficient iterators. |
| |
| generic |
| with procedure Process (Node : Node_Access; Position : Hash_Type); |
| procedure Generic_Iteration_With_Position (HT : Hash_Table_Type); |
| -- Calls Process for each node in hash table HT |
| |
| generic |
| with procedure Process (Node : Node_Access); |
| procedure Generic_Iteration (HT : Hash_Table_Type); |
| -- Calls Process for each node in hash table HT |
| |
| generic |
| use Ada.Streams; |
| with procedure Write |
| (Stream : not null access Root_Stream_Type'Class; |
| Node : Node_Access); |
| procedure Generic_Write |
| (Stream : not null access Root_Stream_Type'Class; |
| HT : Hash_Table_Type); |
| -- Used to implement the streaming attribute for hashed containers. It |
| -- calls Write for each node to write its value into Stream. |
| |
| generic |
| use Ada.Streams; |
| with function New_Node |
| (Stream : not null access Root_Stream_Type'Class) |
| return Node_Access; |
| procedure Generic_Read |
| (Stream : not null access Root_Stream_Type'Class; |
| HT : out Hash_Table_Type); |
| -- Used to implement the streaming attribute for hashed containers. It |
| -- first clears hash table HT, then populates the hash table by calling |
| -- New_Node for each item in Stream. |
| |
| function New_Buckets (Length : Hash_Type) return Buckets_Access; |
| pragma Inline (New_Buckets); |
| -- Allocate a new Buckets_Type array with bounds 0 .. Length - 1 |
| |
| procedure Free_Buckets (Buckets : in out Buckets_Access); |
| pragma Inline (Free_Buckets); |
| -- Unchecked_Deallocate Buckets |
| |
| -- Note: New_Buckets and Free_Buckets are needed because Buckets_Access has |
| -- an empty pool. |
| |
| end Ada.Containers.Hash_Tables.Generic_Operations; |
