/****************************************************************************
 * net/pkt/pkt.h
 *
 *   Copyright (C) 2014 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.
 *
 ****************************************************************************/

#ifndef _NET_PKT_PKT_H
#define _NET_PKT_PKT_H

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/types.h>
#include <queue.h>

#ifdef CONFIG_NET_PKT

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

/* Allocate a new packet socket data callback */

#define pkt_callback_alloc(dev,conn) \
  devif_callback_alloc(dev, &conn->list)
#define pkt_callback_free(dev,conn,cb) \
  devif_conn_callback_free(dev, cb, &conn->list)

/****************************************************************************
 * Public Type Definitions
 ****************************************************************************/

/* Representation of a packet socket connection */

struct devif_callback_s; /* Forward reference */

struct pkt_conn_s
{
  dq_entry_t node;     /* Supports a double linked list */
  uint8_t    lmac[6];  /* The local Ethernet address in network byte order */
  uint8_t    ifindex;
  uint16_t   proto;
  uint8_t    crefs;    /* Reference counts on this instance */

  /* Defines the list of packet callbacks */

  struct devif_callback_s *list;
};

/****************************************************************************
 * Public Data
 ****************************************************************************/

#ifdef __cplusplus
#  define EXTERN extern "C"
extern "C"
{
#else
#  define EXTERN extern
#endif

/****************************************************************************
 * Public Function Prototypes
 ****************************************************************************/

struct net_driver_s; /* Forward reference */
struct eth_hdr_s;    /* Forward reference */

/****************************************************************************
 * Name: pkt_initialize()
 *
 * Description:
 *   Initialize the packet socket connection structures.  Called once and
 *   only from the network initialization logic.
 *
 ****************************************************************************/

void pkt_initialize(void);

/****************************************************************************
 * Name: pkt_palloc()
 *
 * Description:
 *   Allocate a new, uninitialized packet socket connection structure. This
 *   is normally something done by the implementation of the socket() API
 *
 ****************************************************************************/

FAR struct pkt_conn_s *pkt_alloc(void);

/****************************************************************************
 * Name: pkt_free()
 *
 * Description:
 *   Free a packet socket connection structure that is no longer in use.
 *   This should be done by the implementation of close().
 *
 ****************************************************************************/

void pkt_free(FAR struct pkt_conn_s *conn);

/****************************************************************************
 * Name: pkt_active()
 *
 * Description:
 *   Find a connection structure that is the appropriate
 *   connection to be used with the provided Ethernet header
 *
 * Assumptions:
 *   This function is called from UIP logic at interrupt level
 *
 ****************************************************************************/

struct pkt_conn_s *pkt_active(FAR struct eth_hdr_s *buf);

/****************************************************************************
 * Name: pkt_nextconn()
 *
 * Description:
 *   Traverse the list of allocated packet connections
 *
 * Assumptions:
 *   This function is called from UIP logic at interrupt level (or with
 *   interrupts disabled).
 *
 ****************************************************************************/

struct pkt_conn_s *pkt_nextconn(FAR struct pkt_conn_s *conn);

/****************************************************************************
 * Name: pkt_callback
 *
 * Description:
 *   Inform the application holding the packet socket of a change in state.
 *
 * Returned Value:
 *   OK if packet has been processed, otherwise ERROR.
 *
 * Assumptions:
 *   This function is called at the interrupt level with interrupts disabled.
 *
 ****************************************************************************/

uint16_t pkt_callback(FAR struct net_driver_s *dev,
                      FAR struct pkt_conn_s *conn, uint16_t flags);

/****************************************************************************
 * Name: pkt_input
 *
 * Description:
 *   Handle incoming packet input
 *
 * Parameters:
 *   dev - The device driver structure containing the received packet
 *
 * Return:
 *   OK  The packet has been processed  and can be deleted
 *   ERROR Hold the packet and try again later. There is a listening socket
 *         but no recv in place to catch the packet yet.
 *
 * Assumptions:
 *   Called from the interrupt level or with interrupts disabled.
 *
 ****************************************************************************/

/* pkt_input() is prototyped in include/nuttx/net/pkt.h */

/****************************************************************************
 * Name: pkt_find_device
 *
 * Description:
 *   Select the network driver to use with the PKT transaction.
 *
 * Input Parameters:
 *   conn - PKT connection structure (not currently used).
 *
 * Returned Value:
 *   A pointer to the network driver to use.
 *
 ****************************************************************************/

FAR struct net_driver_s *pkt_find_device(FAR struct pkt_conn_s *conn);

/****************************************************************************
 * Name: pkt_poll
 *
 * Description:
 *   Poll a packet "connection" structure for availability of TX data
 *
 * Parameters:
 *   dev - The device driver structure to use in the send operation
 *   conn - The packet "connection" to poll for TX data
 *
 * Return:
 *   None
 *
 * Assumptions:
 *   Called from the interrupt level or with interrupts disabled.
 *
 ****************************************************************************/

void pkt_poll(FAR struct net_driver_s *dev, FAR struct pkt_conn_s *conn);

/****************************************************************************
 * Name: psock_pkt_send
 *
 * Description:
 *   The psock_pkt_send() call may be used only when the packet socket is in a
 *   connected state (so that the intended recipient is known).
 *
 * Parameters:
 *   psock    An instance of the internal socket structure.
 *   buf      Data to send
 *   len      Length of data to send
 *
 * 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.
 *   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:
 *
 ****************************************************************************/

struct socket;
ssize_t psock_pkt_send(FAR struct socket *psock, FAR const void *buf,
                       size_t len);

#undef EXTERN
#ifdef __cplusplus
}
#endif

#endif /* CONFIG_NET_PKT */
#endif /* _NET_PKT_PKT_H */
