TaskbarDll.dpr

{
  DLL system hooking for mouse's position, taskbar drawing, etc.

  Currently it hooks mouse position in order no to use delphi's method
  which is not really appropriate, but it has disadvantages on privileged
  levels windows on focus, it won't work.
}
library TaskbarDll;

{ Important note about DLL memory management: ShareMem must be the
  first unit in your library's USES clause AND your project's (select
  Project-View Source) USES clause if your DLL exports any procedures or
  functions that pass strings as parameters or function results. This
  applies to all strings passed to and from your DLL--even those that
  are nested in records and classes. ShareMem is the interface unit to
  the BORLNDMM.DLL shared memory manager, which must be deployed along
  with your DLL. To avoid using BORLNDMM.DLL, pass string information
  using PChar or ShortString parameters. }

uses
  System.SysUtils,
  System.Classes,
  Variants,
  Winapi.Windows,
  DWMAPI,
  Messages,
  DDetours;

{$R *.res}
const
  MemMapFile ='TaskbarDocks';

  WCA_ACCENT_POLICY = 19;
  ACCENT_ENABLE_GRADIENT = 1;
  ACCENT_ENABLE_TRANSPARENTGRADIENT = 2;
  ACCENT_ENABLE_BLURBEHIND = 3;
  ACCENT_ENABLE_BLURBEHINDFLUENT = 4;
  ACCENT_DEFAULT = 99;

type
  AccentPolicy = packed record
    AccentState: Integer;
    AccentFlags: Integer;
    GradientColor: Integer;
    AnimationId: Integer;
  end;

  WindowCompositionAttributeData = packed record
    Attribute: Cardinal;
    Data: Pointer;
    SizeOfData: Integer;
  end;

  PDLLGlobal = ^TDLLGlobal;
  TDLLGlobal = packed record
    HookHandle: HHOOK;
  end;

var
  GlobalData: PDLLGlobal;
  MMF: THandle;

  TrampolineMessageBoxW: function(hWnd: HWND; lpText, lpCaption: LPCWSTR; uType: UINT): Integer;
  stdcall = nil;
  TrampolineSetWindowCompositionAttribute: function (hWnd: HWND; var data: WindowCompositionAttributeData): Integer;
  stdcall = nil;

function SetWindowCompositionAttribute(Wnd: HWND; const AttrData: WindowCompositionAttributeData): BOOL; stdcall;
  external user32 Name 'SetWindowCompositionAttribute';

function SetWindowCompositionAttributeHooked (hWnd: HWND; var data: WindowCompositionAttributeData): Integer;
var
  accent: AccentPolicy;
  _data: WindowCompositionAttributeData;
begin
  if hwnd = FindWindow('Shell_TrayWnd',nil) then
  begin
    OutputDebugString(PChar('HWND: '+inttostr(hwnd)));
    accent.AccentState := ACCENT_ENABLE_TRANSPARENTGRADIENT;
    accent.GradientColor := $00000;//accent.GradientColor;
    _data.Attribute := WCA_ACCENT_POLICY;
    _data.SizeOfData := SizeOf(accent);
    _data.Data := @accent;
  end
  else
    _data := data;

  Result := TrampolineSetWindowCompositionAttribute(hWnd, _data);
end;

function StartThread(pFunction: TFNThreadStartRoutine;
            iPriority: Integer = THREAD_PRIORITY_NORMAL;
            iStartFlag: Integer = 0): THandle;
var
  ThreadId: DWORD;
begin
  Result := CreateThread(nil, 0, pFunction, nil, iStartFlag, ThreadId);
  if Result <> NULL then
    SetThreadPriority(Result, iPriority);
end;

function CloseThread(ThreadHandle: THandle): Boolean;
begin
  Result := TerminateThread(ThreadHandle, 1);
  CloseHandle(ThreadHandle);
end;

procedure ThisIsTheThread;
begin
//  MessageBoxW(0, 'Hola chico', 'ñol', 0);
  @TrampolineSetWindowCompositionAttribute
    := InterceptCreate(@SetWindowCompositionAttribute,@SetWindowCompositionAttributeHooked);
end;

procedure Run;
var
  hThread: THandle;
begin
  hThread := StartThread(@ThisIsTheThread);
  hThread := StartThread(@ThisIsTheThread, THREAD_PRIORITY_ERROR_RETURN);
  CloseThread(hThread);
end;

procedure mydllproc(Reason: Integer);
begin
  case Reason of
    DLL_PROCESS_ATTACH:
    begin
      OutputDebugString('hola');
      Run;
    end;
    DLL_PROCESS_DETACH:
    begin
      if Assigned(@TrampolineSetWindowCompositionAttribute) then
      begin
        InterceptRemove(@TrampolineSetWindowCompositionAttribute);
        TrampolineSetWindowCompositionAttribute := nil;
      end;
    end;
  end;
end;

function MouseProc(Code: Integer; wParam: WPARAM; lParam: LPARAM): HRESULT; stdcall;
var
  TargetWnd: THandle;
  Msg: PCopyDataStruct;
begin
  if (Code < 0) or (Code = HC_NOREMOVE) then
  begin
    Result := CallNextHookEx(GlobalData^.HookHandle, Code, wParam, lParam);
    Exit;
  end;

  if (wParam = WM_MOUSEMOVE) then
  begin
    TargetWnd := FindWindow('TaskbarDocks', nil);
    if TargetWnd <> 0 then
    begin
      New(Msg);

      Msg^.dwData := 0;
      Msg^.cbData := SizeOf(TMouseHookStruct) + 1;
      Msg^.lpData := PMouseHookStruct(lParam);
      SendMessageTimeout(TargetWnd, WM_COPYDATA, 0, Integer(Msg), SMTO_ABORTIFHUNG, 50, nil);

      Dispose(Msg);
    end;
  end;

  Result := CallNextHookEx(GlobalData^.HookHandle, Code, wParam, lParam);
end;

procedure CreateGlobalHeap;
begin
  MMF := CreateFileMapping(INVALID_HANDLE_VALUE, nil, PAGE_READWRITE, 0, SizeOf(TDLLGlobal), MemMapFile);

  if MMF = 0 then
  begin
    MessageBox(0, 'CreateFileMapping failed', '', 0);
    Exit;
  end;

  GlobalData := MapViewOfFile(MMF, FILE_MAP_ALL_ACCESS, 0, 0, SizeOf(TDLLGlobal));
  if GlobalData = nil then
  begin
    CloseHandle(MMF);
    MessageBox(0, 'MapViewFile failed', '', 0);
  end;
end;

procedure DeleteGlobalHeap;
begin
  if GlobalData <> nil then
    UnmapViewOfFile(GlobalData);

  if MMF <> INVALID_HANDLE_VALUE then
    CloseHandle(MMF);
end;

procedure RunHook; stdcall;
begin
OutputDebugString('empezamos');
  GlobalData^.HookHandle := SetWindowsHookEx(WH_MOUSE_LL, @MouseProc, HInstance, 0);
  if GlobalData^.HookHandle = INVALID_HANDLE_VALUE then
  begin
    MessageBox(0, 'Error', '', MB_OK);
    Exit;
  end;
end;

procedure KillHook; stdcall;
begin
  if (GlobalData <> nil) and (GlobalData^.HookHandle <> INVALID_HANDLE_VALUE) then
    UnhookWindowsHookEx(GlobalData^.HookHandle);
end;

procedure DLLEntry(dwReason: DWORD);
begin
  case dwReason of
    DLL_PROCESS_ATTACH: CreateGlobalHeap;
    DLL_PROCESS_DETACH: DeleteGlobalHeap;
  end;
end;

exports
  KillHook,
  RunHook;

begin
  OutputDebugString('empezamos');
  DllProc := @DllEntry; //mydllproc;
  DllEntry(DLL_PROCESS_ATTACH); //mydllproc(DLL_PROCESS_ATTACH);
end.