message: fix swoole_file_size bugs.
diff: @@ -534,6 +534,11 @@ long swoole_file_size(char *filename)
  SwooleG.error = errno;
  return -1;
  }
  + if ((file_stat.st_mode & S_IFMT) != S_IFREG)
  + {
  + SwooleG.error = EISDIR;
  + return -1;
  + }
  return file_stat.st_size;
  }
  