------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- G N A T . D Y N A M I C _ T A B L E S -- -- -- -- B o d y -- -- -- -- Copyright (C) 2000-2004 Ada Core Technologies, 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 2, 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. See the GNU General Public License -- -- for more details. You should have received a copy of the GNU General -- -- Public License distributed with GNAT; see file COPYING. If not, write -- -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- -- MA 02111-1307, USA. -- -- -- -- As a special exception, if other files instantiate generics from this -- -- unit, or you link this unit with other files to produce an executable, -- -- this unit does not by itself cause the resulting executable to be -- -- covered by the GNU General Public License. This exception does not -- -- however invalidate any other reasons why the executable file might be -- -- covered by the GNU Public License. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with GNAT.Heap_Sort_G; with System; use System; with System.Memory; use System.Memory; with Unchecked_Conversion; package body GNAT.Dynamic_Tables is Min : constant Integer := Integer (Table_Low_Bound); -- Subscript of the minimum entry in the currently allocated table ----------------------- -- Local Subprograms -- ----------------------- procedure Reallocate (T : in out Instance); -- Reallocate the existing table according to the current value stored -- in Max. Works correctly to do an initial allocation if the table -- is currently null. pragma Warnings (Off); -- These unchecked conversions are in fact safe, since they never -- generate improperly aliased pointer values. function To_Address is new Unchecked_Conversion (Table_Ptr, Address); function To_Pointer is new Unchecked_Conversion (Address, Table_Ptr); pragma Warnings (On); -------------- -- Allocate -- -------------- procedure Allocate (T : in out Instance; Num : Integer := 1) is begin T.P.Last_Val := T.P.Last_Val + Num; if T.P.Last_Val > T.P.Max then Reallocate (T); end if; end Allocate; ------------ -- Append -- ------------ procedure Append (T : in out Instance; New_Val : Table_Component_Type) is begin Increment_Last (T); T.Table (Table_Index_Type (T.P.Last_Val)) := New_Val; end Append; -------------------- -- Decrement_Last -- -------------------- procedure Decrement_Last (T : in out Instance) is begin T.P.Last_Val := T.P.Last_Val - 1; end Decrement_Last; -------------- -- For_Each -- -------------- procedure For_Each (Table : Instance) is Quit : Boolean := False; begin for Index in Table_Low_Bound .. Table_Index_Type (Table.P.Last_Val) loop Action (Index, Table.Table (Index), Quit); exit when Quit; end loop; end For_Each; ---------- -- Free -- ---------- procedure Free (T : in out Instance) is begin Free (To_Address (T.Table)); T.Table := null; T.P.Length := 0; end Free; -------------------- -- Increment_Last -- -------------------- procedure Increment_Last (T : in out Instance) is begin T.P.Last_Val := T.P.Last_Val + 1; if T.P.Last_Val > T.P.Max then Reallocate (T); end if; end Increment_Last; ---------- -- Init -- ---------- procedure Init (T : in out Instance) is Old_Length : constant Integer := T.P.Length; begin T.P.Last_Val := Min - 1; T.P.Max := Min + Table_Initial - 1; T.P.Length := T.P.Max - Min + 1; -- If table is same size as before (happens when table is never -- expanded which is a common case), then simply reuse it. Note -- that this also means that an explicit Init call right after -- the implicit one in the package body is harmless. if Old_Length = T.P.Length then return; -- Otherwise we can use Reallocate to get a table of the right size. -- Note that Reallocate works fine to allocate a table of the right -- initial size when it is first allocated. else Reallocate (T); end if; end Init; ---------- -- Last -- ---------- function Last (T : in Instance) return Table_Index_Type is begin return Table_Index_Type (T.P.Last_Val); end Last; ---------------- -- Reallocate -- ---------------- procedure Reallocate (T : in out Instance) is New_Length : Integer; New_Size : size_t; begin if T.P.Max < T.P.Last_Val then while T.P.Max < T.P.Last_Val loop New_Length := T.P.Length * (100 + Table_Increment) / 100; if New_Length > T.P.Length then T.P.Length := New_Length; else T.P.Length := T.P.Length + 1; end if; T.P.Max := Min + T.P.Length - 1; end loop; end if; New_Size := size_t ((T.P.Max - Min + 1) * (Table_Type'Component_Size / Storage_Unit)); if T.Table = null then T.Table := To_Pointer (Alloc (New_Size)); elsif New_Size > 0 then T.Table := To_Pointer (Realloc (Ptr => To_Address (T.Table), Size => New_Size)); end if; if T.P.Length /= 0 and then T.Table = null then raise Storage_Error; end if; end Reallocate; ------------- -- Release -- ------------- procedure Release (T : in out Instance) is begin T.P.Length := T.P.Last_Val - Integer (Table_Low_Bound) + 1; T.P.Max := T.P.Last_Val; Reallocate (T); end Release; -------------- -- Set_Item -- -------------- procedure Set_Item (T : in out Instance; Index : Table_Index_Type; Item : Table_Component_Type) is begin if Integer (Index) > T.P.Last_Val then Set_Last (T, Index); end if; T.Table (Index) := Item; end Set_Item; -------------- -- Set_Last -- -------------- procedure Set_Last (T : in out Instance; New_Val : Table_Index_Type) is begin if Integer (New_Val) < T.P.Last_Val then T.P.Last_Val := Integer (New_Val); else T.P.Last_Val := Integer (New_Val); if T.P.Last_Val > T.P.Max then Reallocate (T); end if; end if; end Set_Last; ---------------- -- Sort_Table -- ---------------- procedure Sort_Table (Table : in out Instance) is Temp : Table_Component_Type; -- A temporary position to simulate index 0 -- Local subprograms function Index_Of (Idx : Natural) return Table_Index_Type; -- Apply Natural to indexs of the table function Lower_Than (Op1, Op2 : Natural) return Boolean; -- Compare two components procedure Move (From : Natural; To : Natural); -- Move one component package Heap_Sort is new GNAT.Heap_Sort_G (Move, Lower_Than); -------------- -- Index_Of -- -------------- function Index_Of (Idx : Natural) return Table_Index_Type is begin return First + Table_Index_Type (Idx) - 1; end Index_Of; ---------- -- Move -- ---------- procedure Move (From : Natural; To : Natural) is begin if From = 0 then Table.Table (Index_Of (To)) := Temp; elsif To = 0 then Temp := Table.Table (Index_Of (From)); else Table.Table (Index_Of (To)) := Table.Table (Index_Of (From)); end if; end Move; ---------------- -- Lower_Than -- ---------------- function Lower_Than (Op1, Op2 : Natural) return Boolean is begin if Op1 = 0 then return Lt (Temp, Table.Table (Index_Of (Op2))); elsif Op2 = 0 then return Lt (Table.Table (Index_Of (Op1)), Temp); else return Lt (Table.Table (Index_Of (Op1)), Table.Table (Index_Of (Op2))); end if; end Lower_Than; -- Start of processing for Sort_Table begin Heap_Sort.Sort (Natural (Last (Table) - First) + 1); end Sort_Table; end GNAT.Dynamic_Tables;