Archive for the ‘Delphi XE3’ Category
Posted by jpluimers on 2014/08/19
Since this did not make it to DelphiFeeds yet: I’ve seen the function PaletteFromDIBColorTable in Graphics.pas go back as far at least until Delphi 2006, and references on the web as far back as Delphi 4.
So: this bug is old, but as it is a security one, make sure you patch soon.
For Delphi XE6, download 29913 BMP Buffer Overflow hotfix – Delphi, C++Builder, RAD Studio XE6.
For older Delphi versions, read this piece that was adapted from the EDN article Delphi and C++ Builder VCL Library Buffer Overflow:
For users of prior versions of Delphi and C++Builder: these steps should be followed to modify the VCL source code and add it to your application.
For each application:
- Add the modified Edit Vcl.Graphics.pas or Graphics.pas or Borland.Vcl.Graphics.pas to your project
- For C++Builder: Under Project | Options | Packages | Runtime Packages, set “Link with runtime packages” to false
- Rebuild your application
Once for the native VCL and .NET VCL:
- Note: Variable names and scoping might be slightly different depending on your product version.
- Edit Vcl.Graphics.pas or Graphics.pas or Borland.Vcl.Graphics.pas
- Locate the function PaletteFromDIBColorTable.
- Add the following code just before the line assigning a value to Pal.palNumEntries when the DIBHandle = 0
if ColorCount > 256 then
InvalidGraphic{$IFNDEF CLR}@{$ENDIF}SInvalidBitmap;;
–jeroen
via Delphi and C++ Builder VCL Library Buffer Overflow.
Posted in Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Development, Software Development | Tagged: Buffer Overflow, Delphi, Delphi versions, vcl | 5 Comments »
Posted by jpluimers on 2014/08/19
I mentioned Delphi managed types is in Delphi “Variant Records”, a few notes indicating they are special.
Managed by the RTL, you can use them to your advantage when you have record types that – when on the stack – are only partially initialized by the RTL: only the managed types are initialized.
Given there is still no support to support “Initialize” and “Finalize” operators (vote for it on [WayBack] QualityCentral) the best you can do was mentioned by LU RD (an alias a very smart Swedish guy Leif Unéus):
Add a dummy string member into your record. Since a string is a managed type it will be initialized to an empty string when the record comes in scope.
So when calling your Clear method, test if the dummy string is empty first. Set the string to a value when appropriate to the use logic to mark the record as initialized.
It reminded me of a managed types idea that former Delphi compiler engineer Barry Kelly once posed to me when I was struggling with the initialization state of nullable records: I wanted the default to be NULL, so I added an extra field managed field “IsInitialized” and the “IsNull” property would negate that field.
Use the Delphi compiler to your advantage (:
–jeroen
via: delphi – Guarantee initialisation of stack record – Stack Overflow.
Posted in Delphi, Delphi XE2, Delphi XE3, Delphi XE4, Development, QC, Software Development | Leave a Comment »
Posted by jpluimers on 2014/08/12
In the With Statement series:
Lars Fosdal – Code Rants
The dreaded with…
Debugging today, I found another gotcha.
In this case, both Self and DisconnectedClient has a property named ClientIdentifier.
Note the difference for the mouse-over and the evaluation.
–jeroen
Read the rest of this entry »
Posted in Appmethod, Borland Pascal, Delphi, Delphi 1, Delphi 2, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Delphi XE7, Development, Pascal, Software Development, Turbo Pascal, With statement | Leave a Comment »
Posted by jpluimers on 2014/08/12
A long while ago, DelphiBasics.info (they are hosted on Google Sites) posted a very interesting via: uExecFromMem unit. It was only a code snippet, not much usage info.
One of the things you can do with this unit, is load the memory image of an executable from a database BLOB, then execute that.
bummi showed this as an uExecFromMemory example on StackOverflow including a small memory leak fix.
It opens way for some interesting deployment scenarios. Not for the everyday ones, but for the occassional situation where a regular deployment is impractical.
–jeroen
via: uExecFromMem by steve10120 – fixed for Win7x64 by testest – DelphiBasics.
Comment by Craig Peterson at G+: https://plus.google.com/109418621512564781181/posts/WZSa6Nt44rK
It’s a handy looking unit, but has a licensing bomb in it: The PerformBaseRelocation routine is lifted directly from BTMemoryModule.pas, which is only licensed LGPL without the binary linking exception. That means providing your DCUs so anyone can relink your app. It’s also a bit less maintainable than BTMemoryModule, since they replaced a bunch of declared constants with magic numbers.
Posted in Delphi, Delphi 2007, Delphi 2009, Delphi 2010, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | 4 Comments »
Posted by jpluimers on 2014/08/07
Following up on yesterdays Delphi: using IInterface to restore cursor at end of mehod (prelude to a memento that executes any code at end of method) here is the memento I meant.
They are based on anonymous methods, which in Delphi are closures: they capture location.
The location is kept just as long as needed, based on a well known Delphi reference counting mechanism: interfaces. The same one I used for the TTemporaryCursor class (and one of the reasons the TTemporaryCursor will keep functioning).
My goal was to simplify code like this:
procedure TTemporaryCursorMainForm.TemporaryCursorClassicButtonClick(Sender: TObject);
var
Button: TButton;
SavedCursor: TCursor;
SavedEnabled: Boolean;
begin
Button := Sender as TButton;
SavedEnabled := Button.Enabled;
try
Button.Enabled := False;
SavedCursor := Screen.Cursor;
try
Screen.Cursor := crHourGlass;
Sleep(3000);
finally
Screen.Cursor := SavedCursor;
end;
finally
Button.Enabled := SavedEnabled;
end;
end;
Into this:
procedure TTemporaryCursorMainForm.TemporaryCursorMementoButtonClick(Sender: TObject);
var
Button: TButton;
SavedEnabled: Boolean;
begin
TTemporaryCursor.SetTemporaryCursor();
Button := Sender as TButton;
SavedEnabled := Button.Enabled;
TAnonymousMethodMemento.CreateMemento(procedure begin Button.Enabled := SavedEnabled; end);
Button.Enabled := False;
Sleep(3000); // sleep 3 seconds with the button disabled crHourGlass cursor
// Delphi will automatically restore the cursor
end;
We’ve already seen one of the try…finally…end blocks vanish by using TTemporaryCursor. Now lets look at TAnonymousMethodMemento:
unit AnonymousMethodMementoUnit;
interface
uses
System.SysUtils;
type
IAnonymousMethodMemento = interface(IInterface)
['{29690E1E-24C8-43A5-8FDF-5F21BB32CEC2}']
end;
TAnonymousMethodMemento = class(TInterfacedObject, IAnonymousMethodMemento)
strict private
FFinallyProc: TProc;
public
constructor Create(const AFinallyProc: TProc);
destructor Destroy; override;
procedure Restore(const AFinallyProc: TProc); virtual;
class function CreateMemento(const AFinallyProc: TProc): IAnonymousMethodMemento;
end;
implementation
{ TAnonymousMethodMemento }
constructor TAnonymousMethodMemento.Create(const AFinallyProc: TProc);
begin
inherited Create();
FFinallyProc := AFinallyProc;
end;
destructor TAnonymousMethodMemento.Destroy;
begin
Restore(FFinallyProc);
inherited Destroy();
end;
class function TAnonymousMethodMemento.CreateMemento(const AFinallyProc: TProc): IAnonymousMethodMemento;
begin
Result := TAnonymousMethodMemento.Create(AFinallyProc);
end;
procedure TAnonymousMethodMemento.Restore(const AFinallyProc: TProc);
begin
AFinallyProc();
end;
end.
Like TTemporaryCursor, I’ve kept it self-contained.
It uses a TProc parameter – a parameterless anonymous method – called AFinallyProc that needs to be executed right before the memento goes out of scope.
It can be called like any method, as to the compiler it is a method.
–jeroen
Posted in Delphi, Delphi 2009, Delphi 2010, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | 11 Comments »
Posted by jpluimers on 2014/08/06
A long while ago, I wrote about a (then overdue post) on .NET/C#: Using IDisposable to restore temporary settrings example: TemporaryCursor class.
I had been using a similar technique in Delphi since before I found out about the [WayBack] TRecall class and thought: I think my TTemporaryCursor is smarter, as it is based on interfaces.
TRecall (and the [WayBack] Vcl.Graphics descendants [WayBack] TBrushRecall, [WayBack] TFontRecall, and [WayBack] TPenRecall) store [WayBack] TPersistent properties using the Assign method. They were introduced in Delphi 6.
Too bad there are only [WayBack] very few people using TRecall as lots of TPersistent things warrant sasaving and restoring.
My [WayBack] TTemporaryCursor (now [WayBack] at bitbucket) class only stores an integer, so it cannot derive from TRecall. Besides it is based on IInterface which got introduced in Delphi 6, but was present as IUnknown since Delphi 3 (see [WayBack] Interface It! A quick guide to the ins and outs of interfaces in Delphi. By Jimmy Tharpe).
This means that TRecall could have been based on IInterface, so I wonder why it was not.
Note I’m not the first to publish about such a class (Malcolm Grooves wrote [WayBack] TCursorSnapshot, SwissDelphiCenter has [WayBack] TMyCursor, Nick Hodges published about [WayBack] TAutoCursor), it’s just that it has been in my tool box for so long, and written memento classes that you will see 2 articles on it this week.
In the mean time (this works with Delphi 2009 and up), I also wrote a small class that does similar things for any [WayBack] anonymous method. More on that tomorrow.
Back to TRecall: it is an example of [WayBack] the memento pattern in Delphi. The [WayBack] memento pattern allows you to restore state.
SourceMaking.com a.k.a. [WayBack] Design Patterns and Refactoring is a great site about [WayBack] Design Patterns, [WayBack] UML, [WayBack] AntiPatterns and [WayBack] Refactoring.
Most pattern example code is available in all of the C#, C++, Delphi, Java and PHP languages.
Great stuff!
One of the constructs for restoring state is a [WayBack] try … finally … end construct: it allows you to always execute something in the finally block, for instance restoring the state to right before the try block. Read the rest of this entry »
Posted in Conference Topics, Conferences, Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Design Patterns, Development, Diagram, Event, Software Development, UML | 14 Comments »
Posted by jpluimers on 2014/08/05
I’ve done a bit of WinWord automation and came across different locations for the API:
New Style:
Old Style:
Fun fact: there is no Old Style Word 2007 documentation any more. You might expect it at http://msdn.microsoft.com/en-us/library/ms263641(v=office.12) but it is not there.
Not so fun fact (and the reason I was looking for the Documents documentation), is because of this big bug ONLY in Office 2010 (it does not occur in Office 2000 .. 2007, and is fixed in 2013): The WordMeister » Bug Word 2010: Documents collection is not correctly maintained.
The only workaround is to run an Office Add-in, or VBA Macro. Both not feasible for external clients.
–jeroen
Posted in Delphi, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Office, Office 2007, Office 2010, Office 2013, Office Automation, Office VBA, Power User, Scripting, Software Development, VBScript | Leave a Comment »
Posted by jpluimers on 2014/08/04
Short answer: do not use the GlobalContainer.
Long answers are in this Spring4D thread: How is the GlobalContainer intended to be used? Are there important don’ts? – Google Groups.
Especially read this message by Stefan Glienke that shows you to setup your main program without using GlobalContainer at all.
Note that this doesn’t mean you should avoid a container at all.
Background information:
–jeroen
Posted in Delphi, Delphi 2010, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE5, Delphi XE6, Development, Software Development, Spring4D | 5 Comments »
Posted by jpluimers on 2014/07/29
ModelMaker Code Explorer (MMX for short) stores the keyboard shortcuts in the registry.
I’ve had it occur once that somehow most (about 95%) of the shortcuts got lost.
Two thinks I learned from resurrecting the shortcuts:
- MMX writes these settings when you exit Delphi
- Only a few keys (with lots of values under them) store the keys.
To resurrect them,
Read the rest of this entry »
Posted in Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 5, Delphi 6, Delphi 7, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/07/24
Late binding sometimes is your friend:
Set objWord = CreateObject("Word.Application")
Wscript.Echo "Version: " & objWord.Version
Wscript.Echo "Build: " & objWord.Build
objWord.Quit
The accompanying Delphi code:
uses
System.Win.ComObj;
procedure TTestVersionAgnosticWordMainForm.GetWordApplicationInfoButtonClick(Sender: TObject);
var
WordApplication: OleVariant;
Version: OleVariant;
Build: OleVariant;
begin
WordApplication := CreateOleObject('Word.Application');
try
try
Version := WordApplication.Version;
Build := WordApplication.Build;
LogMemo.Lines.Add(Version);
LogMemo.Lines.Add(Build);
finally
WordApplication.Quit;
end;
finally
WordApplication := Unassigned; // release it
end;
end;
–jeroen
via: How Can I Determine Which Version of Word is Installed on a Computer? – Hey, Scripting Guy! Blog – Site Home – TechNet Blogs.
Posted in Delphi, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Scripting, Software Development, VBScript | 10 Comments »
The Wiert Corner - irregular stream of stuff 