message: Don't create 4GB empty string if logfile fails to read properly.
diff: @@ -648,11 +648,19 @@ std::string logfile_readall(const char *filename)
  {
  DWORD len = GetFileSize(h, NULL);
  + if(len == INVALID_FILE_SIZE)
  + {
  + DWORD err = GetLastError();
  + ret = StringFormat::Fmt("Failed to read logfile, GetFileSize() threw %u", err);
  + }
  + else
  + {
  ret.resize(len);
  DWORD dummy = len;
  ReadFile(h, &ret[0], len, &dummy, NULL);
  + }
  CloseHandle(h);
  }
  