Question

我的DLL如何检测它是隐式还是显式加载？

示例MyTestDll.dll

library MyTestDll;

uses SimpleShareMem, Windows, Dialogs;

procedure DetectMethodDllLoad: bool;
begin
  // ?????
  // need to detect loading method - implicit or explicit
end;

procedure MyTest; stdcall;
begin
  if DetectMethodDllLoad then
    ShowMessage('Working Program1 (implicit dll load)')
  else
    ShowMessage('Working Program2 (explicit dll load)');
end;

exports MyTest;

begin
end.

Program1.exe（隐式dll加载）

procedure MyTest; stdcall; external 'MyTestDll.dll' Name 'MyTest';

procedure TForm1.Button1Click(Sender: TObject);
begin
  MyTest;
end;

Program2.exe（显式dll加载）

type
  TMyTest = procedure; stdcall;

procedure TForm1.Button1Click(Sender: TObject);
var
  MyTest: TMyTest;
  H: HModule;
begin
  H := LoadLibrary('MyTestDll.dll');
  if H = 0 then
    exit;
  @MyTest := GetProcAddress(H, 'MyTest');
  if Assigned(MyTest) then
    MyTest;
  FreeLibrary(H);
end;

如何实施DetectMethodDllLoad？

Answer 1

如果您可以创建DllMain过程，则DLL_PROCESS_ATTACH调用的lpReserved参数将告诉您加载是静态还是动态。

http://msdn.microsoft.com/en-us/library/ms682583%28VS.85%29.aspx

你当然可以在C中这样做。我不知道Delphi中是否可行。

Answer 2

这是一个非常好的教程，包含2种方法，静态和动态：

Static vs. Dynamic Dynamic Link Library Loading - A Comparison

Answer 3

谢谢Harry Johnston !!! ：）

library MyTestDll;  

uses SimpleShareMem, Windows, Dialogs;  

type
PDllEntryPointFrame = ^TDllEntryPointFrame;
TDllEntryPointFrame = packed record
hModule: THandle; // DLL module handle
dwReason: DWord; // reason for calling DLLEntryPoint function of DLL
bStatic: LongBool; // TRUE if DLL is loading/unloading satically, FALSE - dinamically
end;

function DetectMethodDllLoad: bool;  
asm
mov edx, [hInstance]
mov eax, ebp
@@nextframe:
cmp [eax + $08].TDllEntryPointFrame.hModule, edx
je @@found
mov eax, [eax]
jmp @@nextframe
@@found:
mov eax, [eax + $08].TDllEntryPointFrame.bStatic
end;

procedure MyTest; stdcall;  
begin  
...
end;  

exports MyTest;  

begin  
  if DetectMethodDllLoad then  
    ShowMessage('Working Program1 (implicit dll load)')  
  else  
    ShowMessage('Working Program2 (explicit dll load)');  
end.

P.S。 Delphi XE中的System.TDLLProcEx 无法正常工作！

library MyTestDll; 

....

procedure MyDLLProcEx(Reason:integer;x:pointer);
begin
if x=nil then showmessage('dyn') else showmessage('stat');
end;

begin
DLLProcEx:=@MyDLLProcEx;
end;

x = nil总是:(

如何判断我的DLL是如何加载的？

3 个答案: