Hook Specials 30: Hook's note

Author:haithink

SendMessage() function send message to not entry message list to wait to get by GetMessage(), Immediate pass on window's function.
Example:
LRESULT CALLBACK MouseProc(
  int nCode,      // hook code
  WPARAM wParam,  // message identifier
  LPARAM lParam   // mouse coordinates
)
{
  return 1;       //Hook function return non-zero value, System isn't send message to program

}
HHOOK g_hKeyboard=NULL;
LRESULT CALLBACK KeyboardProc(
  int code,       // hook code
  WPARAM wParam,  // virtual-key code
  LPARAM lParam   // keystroke-message information
)
{
if(VK_SPACE==wParam)//Only shield space key, Mouse can  right click, use go to definition to view other virtual key

      return 1;
//if(VK_F4==wParam&&(1==(lParam>>29&1)))
  //return 1; 
//Shield Alt+F4，lParam第29位请查MSDN
  else
    return ::CallNextHookEx(g_hKeyboard,code,wParam,lParam);
}
BOOL CHookDemoDlg::OnInitDialog()
{
…….
::SetWindowsHookEx(WH_MOUSE,MouseProc,NULL,::GetCurrentThreadId());
  g_hKeyboard=::SetWindowsHookEx(WH_KEYBOARD,KeyboardProc,NULL,::GetCurrentThreadId());
}
Create back door for oneself program
Write the hook function:
LRESULT CALLBACK KeyboardProc(
  int code,       // hook code
  WPARAM wParam,  // virtual-key code
  LPARAM lParam   // keystroke-message information
)
{
//  if(VK_SPACE==wParam)
/*  if(VK_F4==wParam&&(1==(lParam>>29&1)))
      return 1;
  else
    return ::CallNextHookEx(g_hKeyboard,code,wParam,lParam);*/
  if(VK_F2==wParam)
  {
    ::SendMessage(g_hWnd,WM_CLOSE,0,0);
    UnhookWindowsHookEx(g_hKeyboard);
    UnhookWindowsHookEx(g_hKeyboard);
  }
  return 1;
}
Let's hook sub is related to all thread, SetWindowsHookEx's four paramter set 0,Thirdly is on dll of hook function.

Install to relevance all thread hook, Hook function wirte on dll, Remember to statement it to export function, in .def.
.dll中
#include<windows.h>
HHOOK g_hMouse;
HHOOK g_hKeyboard=NULL;
HWND g_hWnd;
/*HINSTANCE g_hInst;

BOOL WINAPI DllMain(
  HINSTANCE hinstDLL,  // handle to the DLL module
  DWORD fdwReason,     // reason for calling function
  LPVOID lpvReserved   // reserved
)
{
  g_hInst=hinstDll;
}
*/
LRESULT CALLBACK MouseProc(
  int nCode,      // hook code
  WPARAM wParam,  // message identifier
  LPARAM lParam   // mouse coordinates
)
{
  return 1;
}

LRESULT CALLBACK KeyboardProc(
  int code,       // hook code
  WPARAM wParam,  // virtual-key code
  LPARAM lParam   // keystroke-message information
)
{
  if(VK_F2==wParam)
  {
    ::SendMessage(g_hWnd,WM_CLOSE,0,0);
    UnhookWindowsHookEx(g_hMouse);
    ::UnhookWindowsHookEx(g_hKeyboard);
  }
  return 1;
}

void SetHook(HWND hwnd)
{ 
  g_hWnd=hwnd;
  g_hKeyboard=::SetWindowsHookEx(WH_KEYBOARD,KeyboardProc,GetModuleHandle("HOOk"),0);
  g_hMouse=::SetWindowsHookEx(WH_MOUSE,MouseProc,::GetModuleHandle("HOOK"),0);
  //::SetWindowsHookEx(WH_MOUSE,MouseProc,g_hInst,0);
}

.def中

LIBRARY HOOK         //此句可无
EXPORTS
SetHook

Aim module, First statement to external import function
_declspec(dllimport)void SetHook(HWND hwnd);
BOOL CHookTestDlg::OnInitDialog()
{
…………..
  int cxScreen,cyScreen;//Full screen current window, On top .
  cxScreen=::GetSystemMetrics(SM_CXSCREEN);
  cyScreen=::GetSystemMetrics(SM_CYSCREEN);
  SetWindowPos(&wndTopMost,0,0,cxScreen,cyScreen,SWP_SHOWWINDOW);

  SetHook(m_hWnd);
}
View Dll section
dumpbin  -headers xxx.dll

Method one in .cpp

#pragma data_seg("MySec")
HWND g_hWnd=NULL;
#pragma data_seg()                 //Define section

#pragma comment(linker,"/section:Mysec,RWS")//设置连接选项

Method two on .cpp

#pragma data_seg("MySec")
HWND g_hWnd=NULL;
#pragma data_seg()                  //Define a section

  on  .def
SEGMENTS
MySec READ WRITE SHARED