incubator-nuttx/net/pkt/pkt_conn.c

252 lines
7.3 KiB
C

/****************************************************************************
* net/pkt/pkt_conn.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* 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/kmalloc.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/netconfig.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/ethernet.h>
#include "devif/devif.h"
#include "pkt/pkt.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#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]))
/****************************************************************************
* Private Data
****************************************************************************/
/* The array containing all packet socket connections */
#ifndef CONFIG_NET_ALLOC_CONNS
static struct pkt_conn_s g_pkt_connections[CONFIG_NET_PKT_CONNS];
#endif
/* A list of all free packet socket connections */
static dq_queue_t g_free_pkt_connections;
static sem_t g_free_sem = SEM_INITIALIZER(1);
/* 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(FAR sem_t *sem)
{
net_lockedwait_uninterruptible(sem);
}
#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)
{
#ifndef CONFIG_NET_ALLOC_CONNS
int i;
for (i = 0; i < CONFIG_NET_PKT_CONNS; i++)
{
dq_addlast(&g_pkt_connections[i].sconn.node, &g_free_pkt_connections);
}
#endif
}
/****************************************************************************
* 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;
#ifdef CONFIG_NET_ALLOC_CONNS
int i;
#endif
/* The free list is protected by a semaphore (that behaves like a mutex). */
_pkt_semtake(&g_free_sem);
#ifdef CONFIG_NET_ALLOC_CONNS
if (dq_peek(&g_free_pkt_connections) == NULL)
{
conn = kmm_zalloc(sizeof(*conn) * CONFIG_NET_PKT_CONNS);
if (conn != NULL)
{
for (i = 0; i < CONFIG_NET_PKT_CONNS; i++)
{
dq_addlast(&conn[i].sconn.node, &g_free_pkt_connections);
}
}
}
#endif
conn = (FAR struct pkt_conn_s *)dq_remfirst(&g_free_pkt_connections);
if (conn)
{
/* Enqueue the connection into the active list */
dq_addlast(&conn->sconn.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 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->sconn.node, &g_active_pkt_connections);
/* Make sure that the connection is marked as uninitialized */
memset(conn, 0, sizeof(*conn));
/* Free the connection */
dq_addlast(&conn->sconn.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)
{
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->sconn.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->sconn.node.flink;
}
}
#endif /* CONFIG_NET && CONFIG_NET_PKT */