incubator-nuttx/net/pkt/pkt_conn.c

270 lines
8.0 KiB
C

/****************************************************************************
* net/pkt/pkt_conn.c
*
* Copyright (C) 2014, 2016-2017 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Large parts of this file were leveraged from uIP logic:
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#if defined(CONFIG_NET) && defined(CONFIG_NET_PKT)
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <arch/irq.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/arp.h>
#include "devif/devif.h"
#include "pkt/pkt.h"
/****************************************************************************
* Private Data
****************************************************************************/
/* The array containing all packet socket connections */
static struct pkt_conn_s g_pkt_connections[CONFIG_NET_PKT_CONNS];
/* A list of all free packet socket connections */
static dq_queue_t g_free_pkt_connections;
static sem_t g_free_sem;
/* A list of all allocated packet socket connections */
static dq_queue_t g_active_pkt_connections;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: _pkt_semtake() and _pkt_semgive()
*
* Description:
* Take/give semaphore
*
****************************************************************************/
static inline void _pkt_semtake(sem_t *sem)
{
int ret;
/* Take the semaphore (perhaps waiting) */
while ((ret = net_lockedwait(sem)) < 0)
{
/* The only case that an error should occur here is if
* the wait was awakened by a signal.
*/
DEBUGASSERT(ret == -EINTR || ret == -ECANCELED);
}
UNUSED(ret);
}
#define _pkt_semgive(sem) nxsem_post(sem)
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pkt_initialize()
*
* Description:
* Initialize the packet socket connection structures. Called once and
* only from the network initialization layer.
*
****************************************************************************/
void pkt_initialize(void)
{
int i;
/* Initialize the queues */
dq_init(&g_free_pkt_connections);
dq_init(&g_active_pkt_connections);
nxsem_init(&g_free_sem, 0, 1);
for (i = 0; i < CONFIG_NET_PKT_CONNS; i++)
{
/* Mark the connection closed and move it to the free list */
g_pkt_connections[i].ifindex = 0;
dq_addlast(&g_pkt_connections[i].node, &g_free_pkt_connections);
}
}
/****************************************************************************
* Name: pkt_alloc()
*
* 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)
{
FAR struct pkt_conn_s *conn;
/* The free list is only accessed from user, non-interrupt level and
* is protected by a semaphore (that behaves like a mutex).
*/
_pkt_semtake(&g_free_sem);
conn = (FAR struct pkt_conn_s *)dq_remfirst(&g_free_pkt_connections);
if (conn)
{
/* Make sure that the connection is marked as uninitialized */
conn->ifindex = 0;
/* Enqueue the connection into the active list */
dq_addlast(&conn->node, &g_active_pkt_connections);
}
_pkt_semgive(&g_free_sem);
return conn;
}
/****************************************************************************
* 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)
{
/* The free list is only accessed from user, non-interrupt level and
* is protected by a semaphore (that behaves like a mutex).
*/
DEBUGASSERT(conn->crefs == 0);
_pkt_semtake(&g_free_sem);
/* Remove the connection from the active list */
dq_rem(&conn->node, &g_active_pkt_connections);
/* Free the connection */
dq_addlast(&conn->node, &g_free_pkt_connections);
_pkt_semgive(&g_free_sem);
}
/****************************************************************************
* 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 network logic at with the network locked.
*
****************************************************************************/
FAR struct pkt_conn_s *pkt_active(FAR struct eth_hdr_s *buf)
{
#define eth_addr_cmp(addr1, addr2) \
((addr1[0] == addr2[0]) && (addr1[1] == addr2[1]) && \
(addr1[2] == addr2[2]) && (addr1[3] == addr2[3]) && \
(addr1[4] == addr2[4]) && (addr1[5] == addr2[5]))
FAR struct pkt_conn_s *conn =
(FAR struct pkt_conn_s *)g_active_pkt_connections.head;
while (conn)
{
/* FIXME lmac in conn should have been set by pkt_bind() */
if (eth_addr_cmp(buf->dest, conn->lmac))
{
/* Matching connection found.. return a reference to it */
break;
}
/* Look at the next active connection */
conn = (FAR struct pkt_conn_s *)conn->node.flink;
}
return conn;
}
/****************************************************************************
* Name: pkt_nextconn()
*
* Description:
* Traverse the list of allocated packet connections
*
* Assumptions:
* This function is called from network logic at with the network locked.
*
****************************************************************************/
FAR struct pkt_conn_s *pkt_nextconn(FAR struct pkt_conn_s *conn)
{
if (!conn)
{
return (FAR struct pkt_conn_s *)g_active_pkt_connections.head;
}
else
{
return (FAR struct pkt_conn_s *)conn->node.flink;
}
}
#endif /* CONFIG_NET && CONFIG_NET_PKT */