text: /*
   *Copyright (C) 2004 Harold L Hunt II All Rights Reserved.
   *
   *Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the
   *"Software"), to deal in the Software without restriction, including
   *without limitation the rights to use, copy, modify, merge, publish,
   *distribute, sublicense, and/or sell copies of the Software, and to
   *permit persons to whom the Software is furnished to do so, subject to
   *the following conditions:
   *
   *The above copyright notice and this permission notice shall be
   *included in all copies or substantial portions of the Software.
   *
   *THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   *EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   *MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   *NONINFRINGEMENT. IN NO EVENT SHALL HAROLD L HUNT II BE LIABLE FOR
   *ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
   *CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   *WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   *Except as contained in this notice, the name of Harold L Hunt II
   *shall not be used in advertising or otherwise to promote the sale, use
   *or other dealings in this Software without prior written authorization
   *from Harold L Hunt II.
   *
   * Authors:	Harold L Hunt II
   */
  
  #ifdef HAVE_XWIN_CONFIG_H
  #include <xwin-config.h>
  #endif
  #include "win.h"
  
  static HHOOK g_hhookKeyboardLL = NULL;
  
  /*
   * Function prototypes
   */
  
  static LRESULT CALLBACK
  winKeyboardMessageHookLL(int iCode, WPARAM wParam, LPARAM lParam);
  
  #ifndef LLKHF_EXTENDED
  #define LLKHF_EXTENDED  0x00000001
  #endif
  #ifndef LLKHF_UP
  #define LLKHF_UP  0x00000080
  #endif
  
  /*
   * KeyboardMessageHook
   */
  
  static LRESULT CALLBACK
  winKeyboardMessageHookLL(int iCode, WPARAM wParam, LPARAM lParam)
  {
      BOOL fPassKeystroke = FALSE;
      BOOL fPassAltTab = TRUE;
      PKBDLLHOOKSTRUCT p = (PKBDLLHOOKSTRUCT) lParam;
      HWND hwnd = GetActiveWindow();
  
  #ifdef XWIN_MULTIWINDOW
      WindowPtr pWin = NULL;
      winPrivWinPtr pWinPriv = NULL;
      winPrivScreenPtr pScreenPriv = NULL;
      winScreenInfo *pScreenInfo = NULL;
  
      /* Check if the Windows window property for our X window pointer is valid */
      if ((pWin = GetProp(hwnd, WIN_WINDOW_PROP)) != NULL) {
          /* Get a pointer to our window privates */
          pWinPriv = winGetWindowPriv(pWin);
  
          /* Get pointers to our screen privates and screen info */
          pScreenPriv = pWinPriv->pScreenPriv;
          pScreenInfo = pScreenPriv->pScreenInfo;
  
          if (pScreenInfo->fMultiWindow)
              fPassAltTab = FALSE;
      }
  #endif
  
      /* Pass keystrokes on to our main message loop */
      if (iCode == HC_ACTION) {
          winDebug("winKeyboardMessageHook: vkCode: %08x scanCode: %08x\n",
                   (unsigned int)p->vkCode, (unsigned int)p->scanCode);
  
          switch (wParam) {
          case WM_KEYDOWN:
          case WM_SYSKEYDOWN:
          case WM_KEYUP:
          case WM_SYSKEYUP:
              fPassKeystroke =
                  (fPassAltTab &&
                   (p->vkCode == VK_TAB) && ((p->flags & LLKHF_ALTDOWN) != 0))
                  || (p->vkCode == VK_LWIN) || (p->vkCode == VK_RWIN);
              break;
          }
      }
  
      /*
       * Pass message on to our main message loop.
       * We process this immediately with SendMessage so that the keystroke
       * appears in, hopefully, the correct order.
       */
      if (fPassKeystroke) {
          LPARAM lParamKey = 0x0;
  
          /* Construct the lParam from KBDLLHOOKSTRUCT */
          lParamKey = lParamKey | (0x0000FFFF & 0x00000001);      /* Repeat count */
          lParamKey = lParamKey | (0x00FF0000 & (p->scanCode << 16));
          lParamKey = lParamKey
              | (0x01000000 & ((p->flags & LLKHF_EXTENDED) << 23));
          lParamKey = lParamKey
              | (0x20000000 & ((p->flags & LLKHF_ALTDOWN) << 24));
          lParamKey = lParamKey | (0x80000000 & ((p->flags & LLKHF_UP) << 24));
  
          /* Send message to our main window that has the keyboard focus */
          PostMessage(hwnd, (UINT) wParam, (WPARAM) p->vkCode, lParamKey);
  
          return 1;
      }
  
      /* Call next hook */
      return CallNextHookEx(NULL, iCode, wParam, lParam);
  }
  
  /*
   * Attempt to install the keyboard hook, return FALSE if it was not installed
   */
  
  Bool
  winInstallKeyboardHookLL(void)
  {
      /* Install the hook only once */
      if (!g_hhookKeyboardLL)
          g_hhookKeyboardLL = SetWindowsHookEx(WH_KEYBOARD_LL,
                                               winKeyboardMessageHookLL,
                                               g_hInstance, 0);
  
      return TRUE;
  }
  
  /*
   * Remove the keyboard hook if it is installed
   */
  
  void
  winRemoveKeyboardHookLL(void)
  {
      if (g_hhookKeyboardLL)
          UnhookWindowsHookEx(g_hhookKeyboardLL);
      g_hhookKeyboardLL = NULL;
  }
  