subsys/system/explorer/bak/shellhook.cpp

   1 /*
   2  * Copyright 2003 Martin Fuchs
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19
  20  //
  21  // Explorer clone
  22  //
  23  // shellhook.cpp
  24  //
  25  // Martin Fuchs, 17.08.2003
  26  //
  27
  28
  29 #include "../utility/utility.h"
  30
  31 #include "shellhook.h"
  32
  33
  34 static HINSTANCE s_hInstance;
  35
  36 struct SharedMem {
  37         HWND    _callback_hwnd;
  38         UINT    _callback_msg;
  39         HHOOK   _hshellHook;
  40 };
  41
  42 static HANDLE s_hMapObject;
  43 static SharedMem* s_pSharedMem;
  44
  45
  46 BOOL APIENTRY DllMain(HINSTANCE hInst, DWORD dwReason, LPVOID)
  47 {
  48         switch(dwReason) {
  49           case DLL_PROCESS_ATTACH: {
  50                 s_hInstance = hInst;
  51                 DisableThreadLibraryCalls(hInst);
  52                 s_hMapObject = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE,
  53                                                                                                 0, sizeof(SharedMem), _T("ROSExplorerShellHookSharedMem"));
  54                 if (!s_hMapObject)
  55                         return FALSE;
  56
  57                  // The first process to attach initializes memory.
  58                 BOOL bInit = GetLastError()!=ERROR_ALREADY_EXISTS;
  59
  60                  // Get a pointer to the file-mapped shared memory.
  61                 s_pSharedMem = (SharedMem*) MapViewOfFile(s_hMapObject, FILE_MAP_WRITE, 0, 0, 0);
  62                 if (!s_pSharedMem)
  63                         return FALSE;
  64
  65                  // Initialize memory if this is the first process.
  66                 if (bInit)
  67                         memset(s_pSharedMem, 0, sizeof(SharedMem));
  68                 break;}
  69
  70           case DLL_PROCESS_DETACH:
  71                 UnmapViewOfFile(s_pSharedMem);
  72                 s_pSharedMem = NULL;
  73                 CloseHandle(s_hMapObject);
  74                 break;
  75         }
  76
  77     return TRUE;
  78 }
  79
  80
  81 static void DoCallBack(int code, WPARAM wparam, LPARAM lparam)
  82 {
  83         UINT callback_msg = s_pSharedMem->_callback_msg;
  84         HWND callback_hwnd = s_pSharedMem->_callback_hwnd;
  85
  86         if (callback_msg)
  87                 PostMessage(callback_hwnd, callback_msg, wparam, code); // lparam unused
  88 }
  89
  90
  91 LRESULT CALLBACK ShellHookProc(int code, WPARAM wparam, LPARAM lparam)
  92 {
  93         DoCallBack(code, wparam, lparam);
  94
  95         return CallNextHookEx(s_pSharedMem->_hshellHook, code, wparam, lparam);
  96 }
  97
  98
  99 void InstallShellHook(HWND callback_hwnd, UINT callback_msg)
 100 {
 101         s_pSharedMem->_callback_hwnd = callback_hwnd;
 102         s_pSharedMem->_callback_msg = callback_msg;
 103
 104         s_pSharedMem->_hshellHook = SetWindowsHookEx(WH_SHELL, ShellHookProc, s_hInstance, 0);
 105 }
 106
 107 void DeinstallShellHook()
 108 {
 109         s_pSharedMem->_callback_hwnd = 0;
 110         s_pSharedMem->_callback_msg = 0;
 111
 112         UnhookWindowsHookEx(s_pSharedMem->_hshellHook);
 113         s_pSharedMem->_hshellHook = 0;
 114 }