/****************************************************************************
* net/socket/send.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/types.h>
#include <sys/socket.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/cancelpt.h>
#include <nuttx/net/net.h>
#include "socket/socket.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: psock_send
*
* Description:
* The psock_send() call may be used only when the socket is in a
* connected state (so that the intended recipient is known). This is an
* internal OS interface. It is functionally equivalent to send() 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.
*
* See comments with send() for more a more complete description of the
* functionality.
*
* Input Parameters:
* psock An instance of the internal socket structure.
* buf Data to send
* len Length of data to send
* flags Send flags
*
* Returned Value:
* On success, returns the number of characters sent. On any failure, a
* negated errno value is returned (See comments with send() for a list
* of the appropriate errno value).
*
****************************************************************************/
ssize_t psock_send(FAR struct socket *psock, FAR const void *buf, size_t len,
int flags)
{
struct msghdr msg;
struct iovec iov;
iov.iov_base = (FAR void *)buf;
iov.iov_len = len;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = 0;
/* And let psock_sendmsg do all of the work */
return psock_sendmsg(psock, &msg, flags);
}
/****************************************************************************
* Name: nx_send
*
* Description:
* The nx_send() call may be used only when the socket is in a
* connected state (so that the intended recipient is known). This is an
* internal OS interface. It is functionally equivalent to send() except
* that:
*
* - It is not a cancellation point, and
* - It does not modify the errno variable.
*
* See comments with send() for more a more complete description of the
* functionality.
*
* Input Parameters:
* sockfd Socket descriptor of the socket
* buf Data to send
* len Length of data to send
* flags Send flags
*
* Returned Value:
* On success, returns the number of characters sent. On any failure, a
* negated errno value is returned (See comments with send() for a list
* of the appropriate errno value).
*
****************************************************************************/
ssize_t nx_send(int sockfd, FAR const void *buf, size_t len, int flags)
{
FAR struct socket *psock;
/* Get the underlying socket structure */
psock = sockfd_socket(sockfd);
/* And let psock_send do all of the work */
return psock_send(psock, buf, len, flags);
}
/****************************************************************************
* Name: send
*
* Description:
* The send() call may be used only when the socket is in a connected state
* (so that the intended recipient is known). The only difference between
* send() and write() is the presence of flags. With zero flags parameter,
* send() is equivalent to write(). Also, send(sockfd,buf,len,flags) is
* equivalent to sendto(sockfd,buf,len,flags,NULL,0).
*
* Input Parameters:
* sockfd Socket descriptor of the socket
* buf Data to send
* len Length of data to send
* flags Send flags
*
* Returned Value:
* On success, returns the number of characters sent. On error,
* -1 is returned, and errno is set appropriately:
*
* EAGAIN or EWOULDBLOCK
* The socket is marked non-blocking and the requested operation
* would block.
* EBADF
* An invalid descriptor was specified.
* ECONNRESET
* Connection reset by peer.
* EDESTADDRREQ
* The socket is not connection-mode, and no peer address is set.
* EFAULT
* An invalid user space address was specified for a parameter.
* EINTR
* A signal occurred before any data was transmitted.
* EINVAL
* Invalid argument passed.
* EISCONN
* The connection-mode socket was connected already but a recipient
* was specified. (Now either this error is returned, or the recipient
* specification is ignored.)
* EMSGSIZE
* The socket type requires that message be sent atomically, and the
* size of the message to be sent made this impossible.
* ENOBUFS
* The output queue for a network interface was full. This generally
* indicates that the interface has stopped sending, but may be
* caused by transient congestion.
* ENOMEM
* No memory available.
* ENOTCONN
* The socket is not connected, and no target has been given.
* ENOTSOCK
* The argument s is not a socket.
* EOPNOTSUPP
* Some bit in the flags argument is inappropriate for the socket
* type.
* EPIPE
* The local end has been shut down on a connection oriented socket.
* In this case the process will also receive a SIGPIPE unless
* MSG_NOSIGNAL is set.
*
* Assumptions:
*
****************************************************************************/
ssize_t send(int sockfd, FAR const void *buf, size_t len, int flags)
{
ssize_t ret;
/* send() is a cancellation point */
enter_cancellation_point();
/* Let psock_send() do all of the work */
ret = nx_send(sockfd, buf, len, flags);
if (ret < 0)
{
_SO_SETERRNO(sockfd_socket(sockfd), -ret);
ret = ERROR;
}
leave_cancellation_point();
return ret;
}