/****************************************************************************
* net/socket/recvmsg.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 <assert.h>
#include <errno.h>
#include <nuttx/cancelpt.h>
#include <nuttx/net/net.h>
#include "socket/socket.h"
#ifdef CONFIG_NET_CMSG
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: psock_recvmsg
*
* Description:
* psock_recvfrom() receives messages from a socket, and may be used to
* receive data on a socket whether or not it is connection-oriented.
* This is an internal OS interface. It is functionally equivalent to
* recvfrom() except that:
*
* - It is not a cancellation point,
* - It does not modify the errno variable, and
* - I accepts the internal socket structure as an input rather than an
* task-specific socket descriptor.
*
* Input Parameters:
* psock - A pointer to a NuttX-specific, internal socket structure
* msg Buffer to receive msg
* len - Length of buffer
* flags - Receive flags
*
* Returned Value:
* On success, returns the number of characters received. If no data is
* available to be received and the peer has performed an orderly shutdown,
* psock_recvmsg() will return 0. Otherwise, on any failure, a negated
* errno value is returned (see comments with recvmsg() for a list of
* appropriate errno values).
*
****************************************************************************/
ssize_t psock_recvmsg(FAR struct socket *psock, FAR struct msghdr *msg,
int flags)
{
/* Verify that non-NULL pointers were passed */
if (msg == NULL)
{
return -EINVAL;
}
if (msg->msg_iovlen != 1)
{
return -ENOTSUP;
}
/* Verify that the sockfd corresponds to valid, allocated socket */
if (psock == NULL || psock->s_conn == NULL)
{
return -EBADF;
}
/* Let logic specific to this address family handle the recvfrom()
* operation.
*/
DEBUGASSERT(psock->s_sockif != NULL &&
(psock->s_sockif->si_recvmsg != NULL ||
psock->s_sockif->si_recvfrom != NULL));
if (psock->s_sockif->si_recvmsg != NULL)
{
return psock->s_sockif->si_recvmsg(psock, msg, flags);
}
else
{
/* Socket doesn't implement si_recvmsg fallback to si_recvfrom */
FAR void *buf = msg->msg_iov->iov_base;
FAR struct sockaddr *from = msg->msg_name;
FAR socklen_t *fromlen = (FAR socklen_t *)&msg->msg_namelen;
size_t len = msg->msg_iov->iov_len;
return psock->s_sockif->si_recvfrom(psock, buf, len, flags, from,
fromlen);
}
}
/****************************************************************************
* Name: nx_recvfrom
*
* Description:
* nx_recvfrom() receives messages from a socket, and may be used to
* receive data on a socket whether or not it is connection-oriented.
* This is an internal OS interface. It is functionally equivalent to
* recvfrom() except that:
*
* - It is not a cancellation point, and
* - It does not modify the errno variable.
*
* Input Parameters:
* sockfd - Socket descriptor of socket
* msg Buffer to receive msg
* len - Length of buffer
* flags - Receive flags
*
* Returned Value:
* On success, returns the number of characters received. If no data is
* available to be received and the peer has performed an orderly shutdown,
* nx_recvmsg() will return 0. Otherwise, on any failure, a negated errno
* value is returned (see comments with recvmsg() for a list of appropriate
* errno values).
*
****************************************************************************/
ssize_t nx_recvmsg(int sockfd, FAR struct msghdr *msg, int flags)
{
FAR struct socket *psock;
/* Get the underlying socket structure */
psock = sockfd_socket(sockfd);
/* Then let psock_recvmsg() do all of the work */
return psock_recvmsg(psock, msg, flags);
}
/****************************************************************************
* Function: recvmsg
*
* Description:
* The recvmsg() call is identical to recvfrom() with a NULL from
* parameter.
*
* Parameters:
* sockfd Socket descriptor of socket
* msg Buffer to receive msg
* len Length of buffer
* flags Receive flags
*
* Returned Value:
* On success, returns the number of characters received. On error,
* -1 is returned, and errno is set appropriately:
*
* EAGAIN
* The socket is marked non-blocking and the receive operation would
* block, or a receive timeout had been set and the timeout expired
* before data was received.
* EBADF
* The argument sockfd is an invalid descriptor.
* ECONNREFUSED
* A remote host refused to allow the network connection (typically
* because it is not running the requested service).
* EFAULT
* The receive buffer pointer(s) point outside the process's address
* space.
* EINTR
* The receive was interrupted by delivery of a signal before any data
* were available.
* EINVAL
* Invalid argument passed.
* ENOMEM
* Could not allocate memory.
* ENOTCONN
* The socket is associated with a connection-oriented protocol and has
* not been connected.
* ENOTSOCK
* The argument sockfd does not refer to a socket.
*
****************************************************************************/
ssize_t recvmsg(int sockfd, FAR struct msghdr *msg, int flags)
{
FAR struct socket *psock;
ssize_t ret;
/* recvfrom() is a cancellation point */
enter_cancellation_point();
/* Get the underlying socket structure */
psock = sockfd_socket(sockfd);
/* Let psock_recvfrom() do all of the work */
ret = psock_recvmsg(psock, msg, flags);
if (ret < 0)
{
_SO_SETERRNO(psock, -ret);
ret = ERROR;
}
leave_cancellation_point();
return ret;
}
#endif /* CONFIG_NET_CMSG */