Method peek

lib/cpp/src/thrift/transport/TSocket.cpp:214–267

}

bool TSocket::peek() {
  if (!isOpen()) {
    return false;
  }
  if (interruptListener_) {
    for (int retries = 0;;) {
      struct THRIFT_POLLFD fds[2];
      std::memset(fds, 0, sizeof(fds));
      fds[0].fd = socket_;
      fds[0].events = THRIFT_POLLIN;
      fds[1].fd = *(interruptListener_.get());
      fds[1].events = THRIFT_POLLIN;
      int ret = THRIFT_POLL(fds, 2, (recvTimeout_ == 0) ? -1 : recvTimeout_);
      int errno_copy = THRIFT_GET_SOCKET_ERROR;
      if (ret < 0) {
        // error cases
        if (errno_copy == THRIFT_EINTR && (retries++ < maxRecvRetries_)) {
          continue;
        }
        TOutput::instance().perror("TSocket::peek() THRIFT_POLL() ", errno_copy);
        throw TTransportException(TTransportException::UNKNOWN, "Unknown", errno_copy);
      } else if (ret > 0) {
        // Check the interruptListener
        if (fds[1].revents & THRIFT_POLLIN) {
          return false;
        }
        // There must be data or a disconnection, fall through to the PEEK
        break;
      } else {
        // timeout
        return false;
      }
    }
  }

  // Check to see if data is available or if the remote side closed
  uint8_t buf;
  int r = static_cast<int>(recv(socket_, cast_sockopt(&buf), 1, MSG_PEEK));
  if (r == -1) {
    int errno_copy = THRIFT_GET_SOCKET_ERROR;
#if defined __FreeBSD__ || defined __MACH__
    /* shigin:
     * freebsd returns -1 and THRIFT_ECONNRESET if socket was closed by
     * the other side
     */
    if (errno_copy == THRIFT_ECONNRESET) {
      return false;
    }
#endif
    TOutput::instance().perror("TSocket::peek() recv() " + getSocketInfo(), errno_copy);
    throw TTransportException(TTransportException::UNKNOWN, "recv()", errno_copy);
  }
  return (r > 0);
}

void TSocket::openConnection(struct addrinfo* res) {