BOOL CChatPipe::CheckRevision(LPCTSTR lpszFileName1, LPCTSTR lpszFileName2,
                   LPCTSTR lpszFileName3, LPCTSTR lpszValueString,
                   DWORD * lpdwVersion, DWORD * lpdwChecksum,
                   LPSTR lpExeInfoString, LPCTSTR lpszMpqFileName)
{
   HANDLE hFile, hFileMapping;
   char * s, lpszFileName[256], cOperations[16];
   int nHashFile, nVariable1[16], nVariable2[16], nVariable3[16], nVariable,
       i, k, nHashOperations;
   DWORD dwTotalSize, dwSize, j, dwBytesRead, dwVariables[4], dwMpqKey,
         * lpdwBuffer;
   LPSTR lpszFileNames[3];
   FILETIME ft;
   SYSTEMTIME st;
   LPBYTE lpbBuffer;
   VS_FIXEDFILEINFO * ffi;

   s = strchr((char *) lpszMpqFileName, '.');
   if (s == NULL)
      return FALSE;
   nHashFile = (int) (*(s - 1) - '0');
   if (nHashFile > 7 || nHashFile < 0)
      return FALSE;
   dwMpqKey = dwMpqChecksumKeys[nHashFile];
   lpszFileNames[0] = (LPSTR) lpszFileName1;
   lpszFileNames[1] = (LPSTR) lpszFileName2;
   lpszFileNames[2] = (LPSTR) lpszFileName3;
   s = (char *) lpszValueString;
   while (*s != '\0')
   {
      if (isalpha(*s))
         nVariable = (int) (toupper(*s) - 'A');
      else
      {
         nHashOperations = (int) (*s - '0');
         s = strchr(s, ' ');
         if (s == NULL)
            return FALSE;
         s++;
         break;
      }
      if (*(++s) == '=')
         s++;
      dwVariables[nVariable] = atol(s);
      s = strchr(s, ' ');
      if (s == NULL)
         return FALSE;
      s++;
   }
   for (i = 0; i < nHashOperations; i++)
   {
      if (!isalpha(*s))
         return FALSE;
      nVariable1[i] = (int) (toupper(*s) - 'A');
      if (*(++s) == '=')
         s++;
      if (toupper(*s) == 'S')
         nVariable2[i] = 3;
      else
         nVariable2[i] = (int) (toupper(*s) - 'A');
      cOperations[i] = *(++s);
      s++;
      if (toupper(*s) == 'S')
         nVariable3[i] = 3;
      else
         nVariable3[i] = (int) (toupper(*s) - 'A');
      s = strchr(s, ' ');
      if (s == NULL)
         break;
      s++;
   }
   dwVariables[0] ^= dwMpqKey;
   for (i = 0; i < 3; i++)
   {
      if (lpszFileNames[i][0] == '\0')
         continue;
      hFile = CreateFile(lpszFileNames[i],
                         GENERIC_READ,
                         FILE_SHARE_READ,
                         NULL,
                         OPEN_EXISTING,
                         FILE_ATTRIBUTE_NORMAL,
                         NULL);
      if (hFile == (HANDLE) INVALID_HANDLE_VALUE)
         return FALSE;
      hFileMapping = CreateFileMapping(hFile, NULL, PAGE_READONLY, 0, 0, NULL);
      if (hFileMapping == NULL)
      {
         CloseHandle(hFile);
         return FALSE;
      }
      lpdwBuffer = (LPDWORD) MapViewOfFile(hFileMapping, FILE_MAP_READ, 0, 0, 0);
      if (lpdwBuffer == NULL)
      {
         CloseHandle(hFileMapping);
         CloseHandle(hFile);
         return FALSE;
      }
      if (i == 0)
      {
         GetFileTime(hFile, &ft, NULL, NULL);
         FileTimeToSystemTime(&ft, &st);
         dwTotalSize = GetFileSize(hFile, NULL);
      }
      dwSize = (GetFileSize(hFile, NULL) / 1024lu) * 1024lu;
      for (j = 0; j < (dwSize / 4lu); j++)
      {
         dwVariables[3] = lpdwBuffer[j];
         for (k = 0; k < nHashOperations; k++)
         {
            switch (cOperations[k])
            {
               case '+':
                  dwVariables[nVariable1[k]] = dwVariables[nVariable2[k]] +
                                               dwVariables[nVariable3[k]];
                  break;
               case '-':
                  dwVariables[nVariable1[k]] = dwVariables[nVariable2[k]] -
                                               dwVariables[nVariable3[k]];
                  break;
               case '^':
                  dwVariables[nVariable1[k]] = dwVariables[nVariable2[k]] ^
                                               dwVariables[nVariable3[k]];
                  break;
               default:
                  return FALSE;
            }
         }
      }
      UnmapViewOfFile(lpdwBuffer);
      CloseHandle(hFileMapping);
      CloseHandle(hFile);
   }
   strcpy(lpszFileName, lpszFileName1);
   dwSize = GetFileVersionInfoSize(lpszFileName, &dwBytesRead);
   lpbBuffer = (LPBYTE) VirtualAlloc(NULL, dwSize, MEM_COMMIT,
                                     PAGE_READWRITE);
   if (lpbBuffer == NULL)
      return FALSE;
   if (GetFileVersionInfo(lpszFileName, NULL, dwSize, lpbBuffer) == FALSE)
      return FALSE;
   if (VerQueryValue(lpbBuffer, "\\", (LPVOID *) &ffi, (PUINT) &dwSize) == FALSE)
      return FALSE;
   *lpdwVersion = ((HIWORD(ffi->dwProductVersionMS) & 0xFF) << 24) |
                  ((LOWORD(ffi->dwProductVersionMS) & 0xFF) << 16) |
                  ((HIWORD(ffi->dwProductVersionLS) & 0xFF) << 8) |
                  (LOWORD(ffi->dwProductVersionLS) & 0xFF);
   VirtualFree(lpbBuffer, 0lu, MEM_RELEASE);
   s = (char *) &lpszFileName[strlen(lpszFileName)-1];
   while (*s != '\\' && s > (char *) lpszFileName)
      s--;
   s++;
   sprintf(lpExeInfoString,
           "%s %02u/%02u/%02u %02u:%02u:%02u %lu",
           s,
           st.wMonth,
           st.wDay,
           st.wYear % 100,
           st.wHour,
           st.wMinute,
           st.wSecond,
           dwTotalSize);
   *lpdwChecksum = dwVariables[2];
   return TRUE;
}