lazarus/lcl/lclrescache.pas
paul d9491a4528 lcl: fix header
git-svn-id: trunk@18002 -
2008-12-31 03:07:17 +00:00

536 lines
15 KiB
ObjectPascal

{
*****************************************************************************
* *
* This file is part of the Lazarus Component Library (LCL) *
* *
* See the file COPYING.modifiedLGPL.txt, included in this distribution, *
* for details about the copyright. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. *
* *
*****************************************************************************
Author: Mattias Gaertner
Abstract:
Types and methods to cache interface resources.
See graphics.pp for examples.
}
unit LCLResCache;
{$mode objfpc}{$H+}
interface
uses
Classes, SysUtils, FPCAdds, Types, LCLType, LCLProc, AvgLvlTree, WSReferences;
{off $DEFINE CheckResCacheConsistency}
type
TResourceCache = class;
TResourceCacheDescriptor = class;
{ TResourceCacheItem }
TResourceCacheItem = class
protected
FDestroying: boolean;
FReferenceCount: integer;
public
Handle: TLCLHandle;
Cache: TResourceCache;
FirstDescriptor, LastDescriptor: TResourceCacheDescriptor;
Next, Prev: TResourceCacheItem;
constructor Create(TheCache: TResourceCache; TheHandle: TLCLHandle);
destructor Destroy; override;
procedure IncreaseRefCount;
procedure DecreaseRefCount;
procedure AddToList(var First, Last: TResourceCacheItem);
procedure RemoveFromList(var First, Last: TResourceCacheItem);
procedure WarnReferenceHigh; virtual;
public
property ReferenceCount: integer read FReferenceCount;
end;
TResourceCacheItemClass = class of TResourceCacheItem;
{ TResourceCacheDescriptor }
TResourceCacheDescriptor = class
protected
FDestroying: boolean;
public
Item: TResourceCacheItem;
Cache: TResourceCache;
Next, Prev: TResourceCacheDescriptor;
constructor Create(TheCache: TResourceCache; TheItem: TResourceCacheItem);
destructor Destroy; override;
procedure AddToList(var First, Last: TResourceCacheDescriptor);
procedure RemoveFromList(var First, Last: TResourceCacheDescriptor);
end;
TResourceCacheDescriptorClass = class of TResourceCacheDescriptor;
{ TResourceCache }
TResourceCache = class
protected
FItems: TAvgLvlTree;
FDescriptors: TAvgLvlTree;
FDestroying: boolean;
FResourceCacheDescriptorClass: TResourceCacheDescriptorClass;
FResourceCacheItemClass: TResourceCacheItemClass;
FMaxUnusedItem: integer; // how many freed resources to keep
FFirstUnusedItem, FLastUnusedItem: TResourceCacheItem;
FUnUsedItemCount: integer;
procedure RemoveItem(Item: TResourceCacheItem); virtual;
procedure RemoveDescriptor(Desc: TResourceCacheDescriptor); virtual;
procedure ItemUsed(Item: TResourceCacheItem);
procedure ItemUnused(Item: TResourceCacheItem);
function ItemIsUsed(Item: TResourceCacheItem): boolean;
public
constructor Create;
procedure Clear;
destructor Destroy; override;
function CompareItems(Tree: TAvgLvlTree; Item1, Item2: Pointer): integer; virtual;
function CompareDescriptors(Tree: TAvgLvlTree; Desc1, Desc2: Pointer): integer; virtual; abstract;
procedure ConsistencyCheck;
public
property MaxUnusedItem: integer read FMaxUnusedItem
write FMaxUnusedItem;
property ResourceCacheItemClass: TResourceCacheItemClass
read FResourceCacheItemClass;
property ResourceCacheDescriptorClass: TResourceCacheDescriptorClass
read FResourceCacheDescriptorClass;
end;
{ THandleResourceCache }
THandleResourceCache = class(TResourceCache)
public
function FindItem(Handle: TLCLHandle): TResourceCacheItem;
end;
{ TBlockResourceCacheDescriptor }
TBlockResourceCacheDescriptor = class(TResourceCacheDescriptor)
public
Data: Pointer;
destructor Destroy; override;
end;
{ TBlockResourceCache }
TBlockResourceCache = class(THandleResourceCache)
private
FDataSize: integer;
protected
FOnCompareDescPtrWithDescriptor: TListSortCompare;
public
constructor Create(TheDataSize: integer);
function FindDescriptor(DescPtr: Pointer): TBlockResourceCacheDescriptor;
function AddResource(Handle: TLCLHandle; DescPtr: Pointer
): TBlockResourceCacheDescriptor;
function CompareDescriptors(Tree: TAvgLvlTree;
Desc1, Desc2: Pointer): integer; override;
public
property DataSize: integer read FDataSize;
property OnCompareDescPtrWithDescriptor: TListSortCompare
read FOnCompareDescPtrWithDescriptor;
end;
function ComparePHandleWithResourceCacheItem(HandlePtr: PLCLHandle; Item:
TResourceCacheItem): integer;
function CompareDescPtrWithBlockResDesc(DescPtr: Pointer;
Item: TBlockResourceCacheDescriptor): integer;
implementation
function ComparePHandleWithResourceCacheItem(HandlePtr: PLCLHandle; Item:
TResourceCacheItem): integer;
begin
Result := CompareLCLHandles(HandlePtr^, Item.Handle);
end;
function CompareDescPtrWithBlockResDesc(DescPtr: Pointer;
Item: TBlockResourceCacheDescriptor): integer;
begin
Result := CompareMemRange(DescPtr, Item.Data,
TBlockResourceCache(Item.Cache).DataSize);
end;
{ TResourceCacheItem }
constructor TResourceCacheItem.Create(TheCache: TResourceCache;
TheHandle: TLCLHandle);
begin
Cache:=TheCache;
Handle:=TheHandle;
end;
destructor TResourceCacheItem.Destroy;
begin
if FDestroying then
RaiseGDBException('');
FDestroying:=true;
Cache.RemoveItem(Self);
//debugln('TResourceCacheItem.Destroy B ',dbgs(Self));
Handle:=0;
inherited Destroy;
//debugln('TResourceCacheItem.Destroy END ',dbgs(Self));
end;
procedure TResourceCacheItem.IncreaseRefCount;
begin
inc(FReferenceCount);
if FReferenceCount=1 then
Cache.ItemUsed(Self);
if (FReferenceCount=1000) or (FReferenceCount=10000) then
WarnReferenceHigh;
end;
procedure TResourceCacheItem.DecreaseRefCount;
procedure RaiseRefCountZero;
begin
RaiseGDBException('TResourceCacheItem.DecreaseRefCount=0 '+ClassName);
end;
begin
//debugln('TResourceCacheItem.DecreaseRefCount ',ClassName,' ',dbgs(Self),' ',dbgs(FReferenceCount));
if FReferenceCount=0 then
RaiseRefCountZero;
dec(FReferenceCount);
if FReferenceCount=0 then
Cache.ItemUnused(Self);
//debugln('TResourceCacheItem.DecreaseRefCount END ');
end;
procedure TResourceCacheItem.AddToList(var First, Last: TResourceCacheItem
);
// add as last
begin
Next:=nil;
Prev:=Last;
Last:=Self;
if First=nil then First:=Self;
if Prev<>nil then Prev.Next:=Self;
end;
procedure TResourceCacheItem.RemoveFromList(var First,Last: TResourceCacheItem);
begin
if First=Self then First:=Next;
if Last=Self then Last:=Prev;
if Next<>nil then Next.Prev:=Prev;
if Prev<>nil then Prev.Next:=Next;
Next:=nil;
Prev:=nil;
end;
procedure TResourceCacheItem.WarnReferenceHigh;
begin
debugln('WARNING: TResourceCacheItem.IncreaseRefCount ',dbgs(FReferenceCount),' ',Cache.ClassName);
end;
{ TResourceCacheDescriptor }
constructor TResourceCacheDescriptor.Create(TheCache: TResourceCache;
TheItem: TResourceCacheItem);
begin
Cache:=TheCache;
Item:=TheItem;
Item.IncreaseRefCount;
AddToList(Item.FirstDescriptor,Item.LastDescriptor);
end;
destructor TResourceCacheDescriptor.Destroy;
begin
if FDestroying then
RaiseGDBException('');
FDestroying:=true;
Cache.RemoveDescriptor(Self);
inherited Destroy;
end;
procedure TResourceCacheDescriptor.AddToList(
var First, Last: TResourceCacheDescriptor);
// add as last
begin
Next:=nil;
Prev:=Last;
Last:=Self;
if First=nil then First:=Self;
if Prev<>nil then Prev.Next:=Self;
end;
procedure TResourceCacheDescriptor.RemoveFromList(
var First, Last: TResourceCacheDescriptor);
begin
if First=Self then First:=Next;
if Last=Self then Last:=Prev;
if Next<>nil then Next.Prev:=Prev;
if Prev<>nil then Prev.Next:=Next;
Next:=nil;
Prev:=nil;
end;
{ TResourceCache }
procedure TResourceCache.RemoveItem(Item: TResourceCacheItem);
begin
if not FDestroying then begin
while Item.FirstDescriptor<>nil do begin
if Item.FirstDescriptor.FDestroying then
RaiseGDBException('TResourceCache.RemoveItem');
Item.FirstDescriptor.Free;
end;
FItems.Remove(Item);
end;
end;
procedure TResourceCache.RemoveDescriptor(Desc: TResourceCacheDescriptor);
var
Item: TResourceCacheItem;
begin
if not FDestroying then begin
Item:=Desc.Item;
if Item<>nil then
Desc.RemoveFromList(Item.FirstDescriptor,Item.LastDescriptor);
FDescriptors.Remove(Desc);
if (Item<>nil) and (Item.FirstDescriptor=nil) and (not Item.FDestroying)
then
Item.Free;
end;
end;
procedure TResourceCache.ItemUsed(Item: TResourceCacheItem);
// called after creation or when Item is used again
begin
if not ItemIsUsed(Item) then begin
// remove from unused list
Item.RemoveFromList(FFirstUnusedItem,FLastUnusedItem);
dec(FUnUsedItemCount);
end;
end;
procedure TResourceCache.ItemUnused(Item: TResourceCacheItem);
// called when Item is not used any more
var
DeleteItem: TResourceCacheItem;
begin
{$IFDEF CheckResCacheConsistency}
ConsistencyCheck;
{$ENDIF}
//debugln('TResourceCache.ItemUnused A ',ClassName,' ',dbgs(Self));
if not ItemIsUsed(Item) then
raise Exception.Create('TResourceCache.ItemUnused');
//debugln('TResourceCache.ItemUnused B ',ClassName,' ',dbgs(Self));
Item.AddToList(FFirstUnusedItem,FLastUnusedItem);
inc(FUnUsedItemCount);
//debugln('TResourceCache.ItemUnused C ',ClassName,' ',dbgs(Self));
if FUnUsedItemCount>FMaxUnusedItem then begin
// maximum unused resources reached -> free the oldest
DeleteItem:=FFirstUnusedItem;
DeleteItem.RemoveFromList(FFirstUnusedItem,FLastUnusedItem);
DeleteItem.Free;
end;
//debugln('TResourceCache.ItemUnused END ',ClassName,' ',dbgs(Self));
end;
function TResourceCache.ItemIsUsed(Item: TResourceCacheItem): boolean;
begin
Result:=(FFirstUnusedItem<>Item) and (Item.Next=nil)
and (Item.Prev=nil)
end;
constructor TResourceCache.Create;
begin
FMaxUnusedItem:=100;
FItems:=TAvgLvlTree.CreateObjectCompare(@CompareItems);
FDescriptors:=TAvgLvlTree.CreateObjectCompare(@CompareDescriptors);
FResourceCacheItemClass:=TResourceCacheItem;
FResourceCacheDescriptorClass:=TResourceCacheDescriptor;
end;
procedure TResourceCache.Clear;
begin
while FFirstUnusedItem<>nil do
FFirstUnusedItem.RemoveFromList(FFirstUnusedItem,FLastUnusedItem);
FItems.FreeAndClear;
FDescriptors.FreeAndClear;
end;
destructor TResourceCache.Destroy;
begin
FDestroying := True;
Clear;
FItems.Free;
FItems := nil;
FDescriptors.Free;
FDescriptors := nil;
inherited Destroy;
end;
function TResourceCache.CompareItems(Tree: TAvgLvlTree; Item1, Item2: Pointer
): integer;
begin
Result:=CompareLCLHandles(TResourceCacheItem(Item1).Handle,
TResourceCacheItem(Item2).Handle);
end;
procedure TResourceCache.ConsistencyCheck;
var
ANode: TAvgLvlTreeNode;
Item: TResourceCacheItem;
Desc: TResourceCacheDescriptor;
Desc2: TResourceCacheDescriptor;
begin
if (FFirstUnusedItem=nil) xor (FLastUnusedItem=nil) then
RaiseGDBException('');
// check items
if FItems.ConsistencyCheck<>0 then
RaiseGDBException('');
ANode:=FItems.FindLowest;
while ANode<>nil do begin
Item:=TResourceCacheItem(ANode.Data);
if Item.FirstDescriptor=nil then
RaiseGDBException('');
if Item.LastDescriptor=nil then
RaiseGDBException('');
if Item.FirstDescriptor.Prev<>nil then
RaiseGDBException('');
if Item.LastDescriptor.Next<>nil then
RaiseGDBException('');
Desc:=Item.FirstDescriptor;
while Desc<>nil do begin
if Desc.Item<>Item then
RaiseGDBException('');
if (Desc.Next<>nil) and (Desc.Next.Prev<>Desc) then
RaiseGDBException('');
if (Desc.Prev<>nil) and (Desc.Prev.Next<>Desc) then
RaiseGDBException('');
if (Desc.Next=nil) and (Item.LastDescriptor<>Desc) then
RaiseGDBException('');
Desc:=Desc.Next;
end;
ANode:=FItems.FindSuccessor(ANode);
end;
// check Descriptors
if FDescriptors.ConsistencyCheck<>0 then
RaiseGDBException('');
ANode:=FDescriptors.FindLowest;
while ANode<>nil do begin
Desc:=TResourceCacheDescriptor(ANode.Data);
Item:=Desc.Item;
if Item=nil then
RaiseGDBException('');
Desc2:=Item.FirstDescriptor;
while (Desc2<>nil) and (Desc2<>Desc) do
Desc2:=Desc2.Next;
if Desc<>Desc2 then
RaiseGDBException('');
ANode:=FItems.FindSuccessor(ANode);
end;
end;
{ THandleResourceCache }
function THandleResourceCache.FindItem(Handle: TLCLHandle): TResourceCacheItem;
var
ANode: TAvgLvlTreeNode;
begin
ANode:=FItems.FindKey(@Handle,
TListSortCompare(@ComparePHandleWithResourceCacheItem));
if ANode<>nil then
Result:=TResourceCacheItem(ANode.Data)
else
Result:=nil;
end;
{ TBlockResourceCache }
constructor TBlockResourceCache.Create(TheDataSize: integer);
begin
inherited Create;
FDataSize:=TheDataSize;
FResourceCacheDescriptorClass:=TBlockResourceCacheDescriptor;
FOnCompareDescPtrWithDescriptor:=
TListSortCompare(@CompareDescPtrWithBlockResDesc);
end;
function TBlockResourceCache.FindDescriptor(DescPtr: Pointer
): TBlockResourceCacheDescriptor;
var
ANode: TAvgLvlTreeNode;
begin
ANode:=FDescriptors.FindKey(DescPtr,FOnCompareDescPtrWithDescriptor);
if ANode<>nil then
Result:=TBlockResourceCacheDescriptor(ANode.Data)
else
Result:=nil;
end;
function TBlockResourceCache.AddResource(Handle: TLCLHandle; DescPtr: Pointer
): TBlockResourceCacheDescriptor;
var
Item: TResourceCacheItem;
procedure RaiseDescriptorAlreadyAdded;
var
Msg: String;
i: Integer;
begin
Msg:='TBlockResourceCache.AddResource Descriptor Already Added '#13;
for i:=0 to DataSize-1 do
Msg:=Msg+HexStr(ord(PChar(DescPtr)[i]),2);
raise Exception.Create(Msg);
end;
begin
{$IFDEF CheckResCacheConsistency}
ConsistencyCheck;
{$ENDIF}
Result:=FindDescriptor(DescPtr);
if Result<>nil then
RaiseDescriptorAlreadyAdded;
Item:=FindItem(Handle);
if Item=nil then begin
Item:=FResourceCacheItemClass.Create(Self,Handle);
FItems.Add(Item);
end;
Result:=TBlockResourceCacheDescriptor(
FResourceCacheDescriptorClass.Create(Self,Item));
ReAllocMem(Result.Data,DataSize);
System.Move(DescPtr^,Result.Data^,DataSize);
FDescriptors.Add(Result);
end;
function TBlockResourceCache.CompareDescriptors(Tree: TAvgLvlTree; Desc1,
Desc2: Pointer): integer;
begin
Result:=CompareMemRange(TBlockResourceCacheDescriptor(Desc1).Data,
TBlockResourceCacheDescriptor(Desc2).Data,
DataSize);
end;
{ TBlockResourceCacheDescriptor }
destructor TBlockResourceCacheDescriptor.Destroy;
begin
inherited Destroy;
ReAllocMem(Data,0);
end;
end.