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/****************************************************************************
* net/net_monitor.c
*
* Copyright (C) 2007-2013 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) && defined(CONFIG_NET_TCP)
#include <stdint.h>
#include <assert.h>
#include <debug.h>
#include "net.h"
#include "uip/uip.h"
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void connection_event(struct uip_conn *conn, uint16_t flags);
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: connection_event
*
* Description:
* Some connection related event has occurred
*
* Parameters:
* conn The connection structure associated with the socket
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
static void connection_event(FAR struct uip_conn *conn, uint16_t flags)
{
FAR struct socket *psock = (FAR struct socket *)conn->connection_private;
if (psock)
{
nllvdbg("flags: %04x s_flags: %02x\n", flags, psock->s_flags);
/* UIP_CLOSE, UIP_ABORT, or UIP_TIMEDOUT: Loss-of-connection events */
if ((flags & (UIP_CLOSE|UIP_ABORT|UIP_TIMEDOUT)) != 0)
{
net_lostconnection(psock, flags);
}
/* UIP_CONNECTED: The socket is successfully connected */
else if ((flags & UIP_CONNECTED) != 0)
{
/* Indicate that the socket is now connected */
psock->s_flags |= _SF_CONNECTED;
psock->s_flags &= ~_SF_CLOSED;
}
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: net_startmonitor
*
* Description:
* Set up to receive TCP connection state changes for a given socket
*
* Input Parameters:
* psock - The socket of interest
*
* Returned Value:
* For now, this function always returns OK.
*
****************************************************************************/
int net_startmonitor(FAR struct socket *psock)
{
FAR struct uip_conn *conn = psock->s_conn;
DEBUGASSERT(psock && conn);
/* Set up to receive callbacks on connection-related events */
conn->connection_private = (void*)psock;
conn->connection_event = connection_event;
/* Check if the connection has already been closed before any callbacks have
* been registered. (Maybe the connection is lost before accept has registered
* the monitoring callback.)
*/
if (!(conn->tcpstateflags == UIP_ESTABLISHED ||
conn->tcpstateflags == UIP_SYN_RCVD))
{
connection_event(conn, UIP_CLOSE);
}
return OK;
}
/****************************************************************************
* Name: net_stopmonitor
*
* Description:
* Stop monitoring TCP connection changes for a given socket
*
* Input Parameters:
* conn - The TCP connection of interest
*
* Returned Value:
* None
*
****************************************************************************/
void net_stopmonitor(FAR struct uip_conn *conn)
{
DEBUGASSERT(conn);
conn->connection_private = NULL;
conn->connection_event = NULL;
}
/****************************************************************************
* Name: net_lostconnection
*
* Description:
* Called when a loss-of-connection event has occurred.
*
* Parameters:
* psock The TCP socket structure associated.
* flags Set of connection events events
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
void net_lostconnection(FAR struct socket *psock, uint16_t flags)
{
DEBUGASSERT(psock)
/* These loss-of-connection events may be reported:
*
* UIP_CLOSE: The remote host has closed the connection
* UIP_ABORT: The remote host has aborted the connection
* UIP_TIMEDOUT: Connection aborted due to too many retransmissions.
*
* And we need to set these two socket status bits appropriately:
*
* _SF_CONNECTED==1 && _SF_CLOSED==0 - the socket is connected
* _SF_CONNECTED==0 && _SF_CLOSED==1 - the socket was gracefully disconnected
* _SF_CONNECTED==0 && _SF_CLOSED==0 - the socket was rudely disconnected
*/
if ((flags & UIP_CLOSE) != 0)
{
/* The peer gracefully closed the connection. Marking the
* connection as disconnected will suppress some subsequent
* ENOTCONN errors from receive. A graceful disconnection is
* not handle as an error but as an "end-of-file"
*/
psock->s_flags &= ~_SF_CONNECTED;
psock->s_flags |= _SF_CLOSED;
}
else if ((flags & (UIP_ABORT|UIP_TIMEDOUT)) != 0)
{
/* The loss of connection was less than graceful. This will (eventually)
* be reported as an ENOTCONN error.
*/
psock->s_flags &= ~(_SF_CONNECTED |_SF_CLOSED);
}
}
#endif /* CONFIG_NET && CONFIG_NET_TCP */
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