/****************************************************************************
* net/uip/uip-tcpappsend.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Adapted for NuttX from logic in uIP which also has a BSD-like license:
*
* Original author Adam Dunkels <adam@dunkels.com>
* Copyright () 2001-2003, Adam Dunkels.
* All rights reserved.
*
* 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. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 <sys/types.h>
#include <debug.h>
#include <net/uip/uipopt.h>
#include <net/uip/uip.h>
#include <net/uip/uip-arch.h>
#include "uip-internal.h"
/****************************************************************************
* Definitions
****************************************************************************/
#define BUF ((struct uip_tcpip_hdr *)&dev->d_buf[UIP_LLH_LEN])
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: uip_tcpappsend
*
* Description:
* Handle application response
*
* Parameters:
* dev - The device driver structure to use in the send operation
* conn - The TCP connection structure holding connection information
* result - App result event sent
*
* Return:
* None
*
* Assumptions:
* Called from the interrupt level or with interrupts disabled.
*
****************************************************************************/
void uip_tcpappsend(struct uip_driver_s *dev, struct uip_conn *conn, uint16 result)
{
/* Handle the result based on the application response */
nvdbg("result: %04x\n", result);
/* Check for connection aborted */
if (result & UIP_ABORT)
{
dev->d_sndlen = 0;
conn->tcpstateflags = UIP_CLOSED;
nvdbg("TCP state: UIP_CLOSED\n");
uip_tcpsend(dev, conn, TCP_RST | TCP_ACK, UIP_IPTCPH_LEN);
}
/* Check for connection closed */
else if (result & UIP_CLOSE)
{
conn->tcpstateflags = UIP_FIN_WAIT_1;
conn->len = 1;
conn->nrtx = 0;
nvdbg("TCP state: UIP_FIN_WAIT_1\n");
dev->d_sndlen = 0;
uip_tcpsend(dev, conn, TCP_FIN | TCP_ACK, UIP_IPTCPH_LEN);
}
/* None of the above */
else
{
/* If d_sndlen > 0, the application has data to be sent. */
if (dev->d_sndlen > 0)
{
/* If the connection has acknowledged data, the contents of
* the ->len variable should be discarded.
*/
if (result & UIP_ACKDATA)
{
conn->len = 0;
}
/* If the ->len variable is non-zero the connection has
* already data in transit and cannot send anymore right
* now.
*/
if (conn->len == 0)
{
/* The application cannot send more than what is
* allowed by the mss (the minumum of the MSS and the
* available window).
*/
if (dev->d_sndlen > conn->mss)
{
dev->d_sndlen = conn->mss;
}
/* Remember how much data we send out now so that we
* know when everything has been acknowledged.
*/
conn->len = dev->d_sndlen;
}
else
{
/* If the application already had unacknowledged data,
* we make sure that the application does not send
* (i.e., retransmit) out more than it previously sent
* out.
*/
dev->d_sndlen = conn->len;
}
}
/* Then handle the rest of the operation just as for the rexmit case */
conn->nrtx = 0;
uip_tcprexmit(dev, conn, result);
}
}
/****************************************************************************
* Name: uip_tcprexmit
*
* Description:
* Handle application retransmission
*
* Parameters:
* dev - The device driver structure to use in the send operation
* conn - The TCP connection structure holding connection information
* result - App result event sent
*
* Return:
* None
*
* Assumptions:
* Called from the interrupt level or with interrupts disabled.
*
****************************************************************************/
void uip_tcprexmit(struct uip_driver_s *dev, struct uip_conn *conn, uint16 result)
{
nvdbg("result: %04x\n", result);
dev->d_appdata = dev->d_snddata;
/* If the application has data to be sent, or if the incoming packet had
* new data in it, we must send out a packet.
*/
if (dev->d_sndlen > 0 && conn->len > 0)
{
/* We always set the ACK flag in response packets adding the length of
* the IP and TCP headers.
*/
uip_tcpsend(dev, conn, TCP_ACK | TCP_PSH, conn->len + UIP_TCPIP_HLEN);
}
/* If there is no data to send, just send out a pure ACK if one is requested`. */
else if (result & UIP_SNDACK)
{
uip_tcpsend(dev, conn, TCP_ACK, UIP_TCPIP_HLEN);
}
/* There is nothing to do -- drop the packet */
else
{
dev->d_len = 0;
}
}
#endif /* CONFIG_NET && CONFIG_NET_TCP */
