base/applications/calc/htmlhelp.c

   1 /*
   2  * ReactOS Calc (HtmlHelp support)
   3  *
   4  * Copyright 2007-2017, Carlo Bramini
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #include "calc.h"
  22
  23 #define GET_CB(name) \
  24     calc_##name = (type_##name)GetProcAddress(hHtmlHelp, #name); \
  25     if (calc_##name == NULL) calc_##name = dummy_##name;
  26
  27 static HWND WINAPI
  28 dummy_HtmlHelpA(HWND hWnd, LPCSTR pszFile, UINT uCommand, DWORD dwData);
  29
  30 static HWND WINAPI
  31 dummy_HtmlHelpW(HWND hWnd, LPCWSTR pszFile, UINT uCommand, DWORD dwData);
  32
  33 type_HtmlHelpA calc_HtmlHelpA = dummy_HtmlHelpA;
  34 type_HtmlHelpW calc_HtmlHelpW = dummy_HtmlHelpW;
  35
  36 static HMODULE hHtmlHelp;
  37
  38 static HWND WINAPI
  39 dummy_HtmlHelpA(HWND hWnd, LPCSTR pszFile, UINT uCommand, DWORD dwData)
  40 {
  41     return NULL;
  42 }
  43
  44 static HWND WINAPI
  45 dummy_HtmlHelpW(HWND hWnd, LPCWSTR pszFile, UINT uCommand, DWORD dwData)
  46 {
  47     return NULL;
  48 }
  49
  50 void HtmlHelp_Start(HINSTANCE hInstance)
  51 {
  52     hHtmlHelp = LoadLibrary(_T("HTMLHELP"));
  53     if (hHtmlHelp == NULL)
  54         return;
  55
  56     GET_CB(HtmlHelpW)
  57     GET_CB(HtmlHelpA)
  58 }
  59
  60 void HtmlHelp_Stop(void)
  61 {
  62     if(hHtmlHelp == NULL)
  63         return;
  64
  65     FreeLibrary(hHtmlHelp);
  66     hHtmlHelp = NULL;
  67 }