text: /*
   * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License").
   * You may not use this file except in compliance with the License.
   * A copy of the License is located at
   *
   *  http://aws.amazon.com/apache2.0
   *
   * or in the "license" file accompanying this file. This file is distributed
   * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
   * express or implied. See the License for the specific language governing
   * permissions and limitations under the License.
   */
  
  #include <s2n.h>
  
  #include "tls/s2n_alerts.h"
  #include "tls/s2n_connection.h"
  #include "tls/s2n_tls.h"
  
  #include "utils/s2n_safety.h"
  
  int s2n_shutdown(struct s2n_connection *conn, s2n_blocked_status * more)
  {
      POSIX_ENSURE_REF(conn);
      POSIX_ENSURE_REF(more);
  
      /* Treat this call as a no-op if already wiped */
      if (conn->send == NULL && conn->recv == NULL) {
          return 0;
      }
  
      uint64_t elapsed;
      POSIX_GUARD_RESULT(s2n_timer_elapsed(conn->config, &conn->write_timer, &elapsed));
      S2N_ERROR_IF(elapsed < conn->delay, S2N_ERR_SHUTDOWN_PAUSED);
  
      /* Queue our close notify, once. Use warning level so clients don't give up */
      POSIX_GUARD(s2n_queue_writer_close_alert_warning(conn));
  
      /* Write it */
      POSIX_GUARD(s2n_flush(conn, more));
  
      /* Assume caller isn't interested in pending incoming data */
      if (conn->in_status == PLAINTEXT) {
          POSIX_GUARD(s2n_stuffer_wipe(&conn->header_in));
          POSIX_GUARD(s2n_stuffer_wipe(&conn->in));
          conn->in_status = ENCRYPTED;
      }
  
      /* Fails with S2N_ERR_SHUTDOWN_RECORD_TYPE or S2N_ERR_ALERT on receipt of anything but a close_notify */
      POSIX_GUARD(s2n_recv_close_notify(conn, more));
  
      return 0;
  }
  