/**
 * \addtogroup uip
 * @{
 */

/**
 * \file
 * Header file for the uIP TCP/IP stack.
 * \author Adam Dunkels <adam@dunkels.com>
 *
 * The uIP TCP/IP stack header file contains definitions for a number
 * of C macros that are used by uIP programs as well as internal uIP
 * structures, TCP/IP header structures and function declarations.
 *
 */


/*
 * Copyright (c) 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.  
 *
 * This file is part of the uIP TCP/IP stack.
 *
 * $Id: uip.h,v 1.1 2004/05/09 00:24:47 Louis Exp $
 *
 */

#ifndef __UIP_H__
#define __UIP_H__

#include "uipopt.h"

/*-----------------------------------------------------------------------------------*/
/* First, the functions that should be called from the
 * system. Initialization, the periodic timer and incoming packets are
 * handled by the following three functions.
 */

/**
 * \defgroup uipconffunc uIP configuration functions
 * @{
 *
 * The uIP configuration functions are used for setting run-time
 * parameters in uIP such as IP addresses. 
 */

/**
 * Set the IP address of this host.
 *
 * The IP address is represented as a 4-byte array where the first
 * octet of the IP address is put in the first member of the 4-byte
 * array.
 *
 * \param addr A pointer to a 4-byte representation of the IP address.
 *
 * \hideinitializer
 */
#define uip_sethostaddr(addr) do { uip_hostaddr[0] = addr[0]; \
                              uip_hostaddr[1] = addr[1]; } while(0)

/**
 * Get the IP address of this host.
 *
 * The IP address is represented as a 4-byte array where the first
 * octet of the IP address is put in the first member of the 4-byte
 * array.
 *
 * \param addr A pointer to a 4-byte array that will be filled in with
 * the currently configured IP address.
 *
 * \hideinitializer
 */
#define uip_gethostaddr(addr) do { addr[0] = uip_hostaddr[0]; \
                              addr[1] = uip_hostaddr[1]; } while(0)

/** @} */

/**
 * \defgroup uipinit uIP initialization functions
 * @{
 *
 * The uIP initialization functions are used for booting uIP.
 */

/**
 * uIP initialization function.
 *
 * This function should be called at boot up to initilize the uIP
 * TCP/IP stack.
 */
void uip_init(void);

/** @} */

/**
 * \defgroup uipdevfunc uIP device driver functions
 * @{
 *
 * These functions are used by a network device driver for interacting
 * with uIP.
 */

/**
 * Process an incoming packet.
 *
 * This function should be called when the device driver has received
 * a packet from the network. The packet from the device driver must
 * be present in the uip_buf buffer, and the length of the packet
 * should be placed in the uip_len variable.
 *
 * When the function returns, there may be an outbound packet placed
 * in the uip_buf packet buffer. If so, the uip_len variable is set to
 * the length of the packet. If no packet is to be sent out, the
 * uip_len variable is set to 0.
 *
 * The usual way of calling the function is presented by the source
 * code below.
 \code
  uip_len = devicedriver_poll();
  if(uip_len > 0) {
    uip_input();
    if(uip_len > 0) {
      devicedriver_send();
    }
  }
 \endcode
 *
 * \note If you are writing a uIP device driver that needs ARP
 * (Address Resolution Protocol), e.g., when running uIP over
 * Ethernet, you will need to call the uIP ARP code before calling
 * this function:
 \code
  #define BUF ((struct uip_eth_hdr *)&uip_buf[0])
  uip_len = ethernet_devicedrver_poll();
  if(uip_len > 0) {
    if(BUF->type == HTONS(UIP_ETHTYPE_IP)) {
      uip_arp_ipin();
      uip_input();
      if(uip_len > 0) {
        uip_arp_out();
	ethernet_devicedriver_send();
      }
    } else if(BUF->type == HTONS(UIP_ETHTYPE_ARP)) {
      uip_arp_arpin();
      if(uip_len > 0) {
	ethernet_devicedriver_send();
      }
    }
 \endcode
 *
 * \hideinitializer
 */
#define uip_input()        uip_process(UIP_DATA)

/**
 * Periodic processing for a connection identified by its number.
 * 
 * This function does the necessary periodic processing (timers,
 * polling) for a uIP TCP conneciton, and should be called when the
 * periodic uIP timer goes off. It should be called for every
 * connection, regardless of whether they are open of closed.
 *
 * When the function returns, it may have an outbound packet waiting
 * for service in the uIP packet buffer, and if so the uip_len
 * variable is set to a value larger than zero. The device driver
 * should be called to send out the packet.
 *
 * The ususal way of calling the function is through a for() loop like
 * this:
 \code
  for(i = 0; i < UIP_CONNS; ++i) {
    uip_periodic(i);
    if(uip_len > 0) {
      devicedriver_send();
    }
  }
 \endcode
 *
 * \note If you are writing a uIP device driver that needs ARP
 * (Address Resolution Protocol), e.g., when running uIP over
 * Ethernet, you will need to call the uip_arp_out() function before
 * calling the device driver:
 \code
  for(i = 0; i < UIP_CONNS; ++i) {
    uip_periodic(i);
    if(uip_len > 0) {
      uip_arp_out();
      ethernet_devicedriver_send();
    }
  }
 \endcode 
 *
 * \param conn The number of the connection which is to be periodically polled.
 *
 * \hideinitializer
 */
#define uip_periodic(conn) do { uip_conn = &uip_conns[conn]; \
                                uip_process(UIP_TIMER); } while (0)

/**
 * Periodic processing for a connection identified by a pointer to its structure.
 *
 * Same as uip_periodic() but takes a pointer to the actual uip_conn
 * struct instead of an integer as its argument. This function can be
 * used to force periodic processing of a specific connection.
 *
 * \param conn A pointer to the uip_conn struct for the connection to
 * be processed.
 *
 * \hideinitializer
 */
#define uip_periodic_conn(conn) do { uip_conn = conn; \
                                     uip_process(UIP_TIMER); } while (0)

#if UIP_UDP
/**
 * Periodic processing for a UDP connection identified by its number.
 *
 * This function is essentially the same as uip_prerioic(), but for
 * UDP connections. It is called in a similar fashion as the
 * uip_periodic() function:
 \code
  for(i = 0; i < UIP_UDP_CONNS; i++) {
    uip_udp_periodic(i);
    if(uip_len > 0) {
      devicedriver_send();
    }
  }   
 \endcode
 *
 * \note As for the uip_periodic() function, special care has to be
 * taken when using uIP together with ARP and Ethernet:
 \code
  for(i = 0; i < UIP_UDP_CONNS; i++) {
    uip_udp_periodic(i);
    if(uip_len > 0) {
      uip_arp_out();
      ethernet_devicedriver_send();
    }
  }   
 \endcode
 *
 * \param conn The number of the UDP connection to be processed.
 *
 * \hideinitializer
 */
#define uip_udp_periodic(conn) do { uip_udp_conn = &uip_udp_conns[conn]; \
                                uip_process(UIP_UDP_TIMER); } while (0)

/**
 * Periodic processing for a UDP connection identified by a pointer to
 * its structure.
 *
 * Same as uip_udp_periodic() but takes a pointer to the actual
 * uip_conn struct instead of an integer as its argument. This
 * function can be used to force periodic processing of a specific
 * connection.
 *
 * \param conn A pointer to the uip_udp_conn struct for the connection
 * to be processed.
 *
 * \hideinitializer
 */
#define uip_udp_periodic_conn(conn) do { uip_udp_conn = conn; \
                                         uip_process(UIP_UDP_TIMER); } while (0)


#endif /* UIP_UDP */

/**
 * The uIP packet buffer.
 *
 * The uip_buf array is used to hold incoming and outgoing
 * packets. The device driver should place incoming data into this
 * buffer. When sending data, the device driver should read the link
 * level headers and the TCP/IP headers from this buffer. The size of
 * the link level headers is configured by the UIP_LLH_LEN define.
 *
 * \note The application data need not be placed in this buffer, so
 * the device driver must read it from the place pointed to by the
 * uip_appdata pointer as illustrated by the following example:
 \code
 void
 devicedriver_send(void)
 {
    hwsend(&uip_buf[0], UIP_LLH_LEN);
    hwsend(&uip_buf[UIP_LLH_LEN], 40);
    hwsend(uip_appdata, uip_len - 40 - UIP_LLH_LEN);
 }
 \endcode
 */
extern u8_t uip_buf[UIP_BUFSIZE+2];

/** @} */

/*-----------------------------------------------------------------------------------*/
/* Functions that are used by the uIP application program. Opening and
 * closing connections, sending and receiving data, etc. is all
 * handled by the functions below.
*/
/**
 * \defgroup uipappfunc uIP application functions
 * @{
 *
 * Functions used by an application running of top of uIP.
 */

/**
 * Start listening to the specified port.
 *
 * \note Since this function expects the port number in network byte
 * order, a conversion using HTONS() or htons() is necessary.
 *
 \code
 uip_listen(HTONS(80)); 
 \endcode
 *
 * \param port A 16-bit port number in network byte order.
 */
void uip_listen(u16_t port);

/**
 * Stop listening to the specified port.
 *
 * \note Since this function expects the port number in network byte
 * order, a conversion using HTONS() or htons() is necessary.
 *
 \code
 uip_unlisten(HTONS(80)); 
 \endcode