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/****************************************************************************
* net/listen.c
*
* Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#if defined(CONFIG_NET) && CONFIG_NSOCKET_DESCRIPTORS > 0
#include <sys/socket.h>
#include <errno.h>
#include <debug.h>
#include "net.h"
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Function: listen
*
* Description:
* To accept connections, a socket is first created with socket(), a
* willingness to accept incoming connections and a queue limit for incoming
* connections are specified with listen(), and then the connections are
* accepted with accept(). The listen() call applies only to sockets of
* type SOCK_STREAM or SOCK_SEQPACKET.
*
* Parameters:
* sockfd Socket descriptor of the bound socket
* backlog The maximum length the queue of pending connections may grow.
* If a connection request arrives with the queue full, the client
* may receive an error with an indication of ECONNREFUSED or,
* if the underlying protocol supports retransmission, the request
* may be ignored so that retries succeed.
*
* Returned Value:
* On success, zero is returned. On error, -1 is returned, and errno is set
* appropriately.
*
* EADDRINUSE
* Another socket is already listening on the same port.
* EBADF
* The argument 'sockfd' is not a valid descriptor.
* ENOTSOCK
* The argument 'sockfd' is not a socket.
* EOPNOTSUPP
* The socket is not of a type that supports the listen operation.
*
* Assumptions:
*
****************************************************************************/
int listen(int sockfd, int backlog)
{
FAR struct socket *psock = sockfd_socket(sockfd);
struct uip_conn *conn;
int err;
/* Verify that the sockfd corresponds to valid, allocated socket */
if (!psock || psock->s_crefs <= 0)
{
/* It is not a valid socket description. Distinguish between the cases
* where sockfd is a just invalid and when it is a valid file descriptor used
* in the wrong context.
*/
#if CONFIG_NFILE_DESCRIPTORS > 0
if ((unsigned int)sockfd < CONFIG_NFILE_DESCRIPTORS)
{
err = ENOTSOCK;
}
else
#endif
{
err = EBADF;
}
goto errout;
}
/* Verify that the sockfd corresponds to a connected SOCK_STREAM */
conn = (struct uip_conn *)psock->s_conn;
if (psock->s_type != SOCK_STREAM || !psock->s_conn || conn->lport <= 0)
{
err = EOPNOTSUPP;
goto errout;
}
/* Set up the backlog for this connection */
#ifdef CONFIG_NET_TCPBACKLOG
err = uip_backlogcreate(conn, backlog);
if (err < 0)
{
err = -err;
goto errout;
}
#endif
/* Start listening to the bound port. This enables callbacks when accept()
* is called and enables poll()/select() logic.
*/
uip_listen(conn);
psock->s_flags |= _SF_LISTENING;
return OK;
errout:
errno = err;
return ERROR;
}
#endif /* CONFIG_NET && CONFIG_NSOCKET_DESCRIPTORS */
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