incubator-nuttx/net/can/can_getsockopt.c

/****************************************************************************
 * net/can/can_getsockopt.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License 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.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/time.h>
#include <stdint.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>

#include <netpacket/can.h>

#include <nuttx/net/net.h>
#include <nuttx/net/can.h>

#include "socket/socket.h"
#include "utils/utils.h"
#include "can/can.h"

#ifdef CONFIG_NET_CANPROTO_OPTIONS

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: can_getsockopt
 *
 * Description:
 *   can_getsockopt() retrieves the value for the option specified by the
 *   'option' argument for the socket specified by the 'psock' argument.  If
 *   the size of the option value is greater than 'value_len', the value
 *   stored in the object pointed to by the 'value' argument will be silently
 *   truncated. Otherwise, the length pointed to by the 'value_len' argument
 *   will be modified to indicate the actual length of the 'value'.
 *
 *   See <sys/socket.h> a complete list of values for the socket-level
 *   'option' argument.  Protocol-specific options are are protocol specific
 *   header files (such as netpacket/can.h for the case of the CAN protocol).
 *
 * Input Parameters:
 *   psock     Socket structure of the socket to query
 *   level     Protocol level to set the option
 *   option    identifies the option to get
 *   value     Points to the argument value
 *   value_len The length of the argument value
 *
 * Returned Value:
 *   Returns zero (OK) on success.  On failure, it returns a negated errno
 *   value to indicate the nature of the error.  See psock_getsockopt() for
 *   the complete list of appropriate return error codes.
 *
 ****************************************************************************/

int can_getsockopt(FAR struct socket *psock, int option,
                   FAR void *value, FAR socklen_t *value_len)
{
  FAR struct can_conn_s *conn;
  int ret = OK;

  DEBUGASSERT(psock != NULL && value != NULL && value_len != NULL &&
              psock->s_conn != NULL);
  conn = (FAR struct can_conn_s *)psock->s_conn;

  if (psock->s_type != SOCK_RAW)
    {
      nerr("ERROR:  Not a RAW CAN socket\n");
      return -ENOTCONN;
    }

  switch (option)
    {
      case CAN_RAW_FILTER:
        if (*value_len % sizeof(struct can_filter) != 0)
          {
            ret = -EINVAL;
          }
        else if (*value_len > CONFIG_NET_CAN_RAW_FILTER_MAX *
                   sizeof(struct can_filter))
          {
            ret = -EINVAL;
          }
        else
          {
            int count = conn->filter_count;

          if (*value_len < count * sizeof(struct can_filter))
              {
                count = *value_len / sizeof(struct can_filter);
              }
          else
            {
              *value_len = count * sizeof(struct can_filter);
            }

            for (int i = 0; i < count; i++)
              {
                ((struct can_filter *)value)[i] = conn->filters[i];
              }

            ret = OK;
          }
        break;

      case CAN_RAW_ERR_FILTER:
        break;

      case CAN_RAW_LOOPBACK:
        if (*value_len < sizeof(conn->loopback))
          {
            /* REVISIT: POSIX says that we should truncate the value if it
             * is larger than value_len.   That just doesn't make sense
             * to me in this case.
             */

            ret              = -EINVAL;
          }
        else
          {
            FAR int32_t *loopback  = (FAR int32_t *)value;
            *loopback              = conn->loopback;
            *value_len             = sizeof(conn->loopback);
            ret                    = OK;
          }
        break;

      case CAN_RAW_RECV_OWN_MSGS:
        if (*value_len < sizeof(conn->recv_own_msgs))
          {
            /* REVISIT: POSIX says that we should truncate the value if it
             * is larger than value_len.   That just doesn't make sense
             * to me in this case.
             */

            ret              = -EINVAL;
          }
        else
          {
            FAR int32_t *recv_own_msgs = (FAR int32_t *)value;
            *recv_own_msgs             = conn->recv_own_msgs;
            *value_len                 = sizeof(conn->recv_own_msgs);
            ret                        = OK;
          }
        break;

#ifdef CONFIG_NET_CAN_CANFD
      case CAN_RAW_FD_FRAMES:
        if (*value_len < sizeof(conn->fd_frames))
          {
            /* REVISIT: POSIX says that we should truncate the value if it
             * is larger than value_len.   That just doesn't make sense
             * to me in this case.
             */

            ret              = -EINVAL;
          }
        else
          {
            FAR int32_t *fd_frames = (FAR int32_t *)value;
            *fd_frames             = conn->fd_frames;
            *value_len             = sizeof(conn->fd_frames);
            ret                    = OK;
          }
        break;
#endif

      case CAN_RAW_JOIN_FILTERS:
        break;

#ifdef CONFIG_NET_CAN_RAW_TX_DEADLINE
      case CAN_RAW_TX_DEADLINE:
        if (*value_len < sizeof(conn->tx_deadline))
          {
            /* REVISIT: POSIX says that we should truncate the value if it
             * is larger than value_len.   That just doesn't make sense
             * to me in this case.
             */

            ret              = -EINVAL;
          }
        else
          {
            FAR int32_t *tx_deadline = (FAR int32_t *)value;
            *tx_deadline             = conn->tx_deadline;
            *value_len               = sizeof(conn->tx_deadline);
            ret                      = OK;
          }
        break;
#endif

      default:
        nerr("ERROR: Unrecognized RAW CAN socket option: %d\n", option);
        ret = -ENOPROTOOPT;
        break;
    }

  return ret;
}

#endif /* CONFIG_NET_CANPROTO_OPTIONS */