incubator-nuttx/net/pkt/pkt_send.c

272 lines
8.6 KiB
C

/****************************************************************************
* net/pkt/pkt_send.c
*
* Copyright (C) 2014, 2016-2017 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#if defined(CONFIG_NET) && defined(CONFIG_NET_PKT)
#include <sys/types.h>
#include <sys/socket.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <arch/irq.h>
#include <nuttx/semaphore.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/net.h>
#include <nuttx/net/ip.h>
#include "netdev/netdev.h"
#include "devif/devif.h"
#include "socket/socket.h"
#include "pkt/pkt.h"
/****************************************************************************
* Private Types
****************************************************************************/
/* This structure holds the state of the send operation until it can be
* operated upon by the event handler.
*/
struct send_s
{
FAR struct socket *snd_sock; /* Points to the parent socket structure */
FAR struct devif_callback_s *snd_cb; /* Reference to callback instance */
sem_t snd_sem; /* Used to wake up the waiting thread */
FAR const uint8_t *snd_buffer; /* Points to the buffer of data to send */
size_t snd_buflen; /* Number of bytes in the buffer to send */
ssize_t snd_sent; /* The number of bytes sent */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: psock_send_eventhandler
****************************************************************************/
static uint16_t psock_send_eventhandler(FAR struct net_driver_s *dev,
FAR void *pvconn,
FAR void *pvpriv, uint16_t flags)
{
FAR struct send_s *pstate = (FAR struct send_s *)pvpriv;
ninfo("flags: %04x sent: %d\n", flags, pstate->snd_sent);
if (pstate)
{
/* Check if the outgoing packet is available. It may have been claimed
* by a send event handler serving a different thread -OR- if the
* output buffer currently contains unprocessed incoming data. In
* these cases we will just have to wait for the next polling cycle.
*/
if (dev->d_sndlen > 0 || (flags & PKT_NEWDATA) != 0)
{
/* Another thread has beat us sending data or the buffer is busy,
* Check for a timeout. If not timed out, wait for the next
* polling cycle and check again.
*/
/* No timeout. Just wait for the next polling cycle */
return flags;
}
/* It looks like we are good to send the data */
else
{
/* Copy the packet data into the device packet buffer and send it */
devif_pkt_send(dev, pstate->snd_buffer, pstate->snd_buflen);
pstate->snd_sent = pstate->snd_buflen;
/* Make sure no ARP request overwrites this ARP request. This
* flag will be cleared in arp_out().
*/
IFF_SET_NOARP(dev->d_flags);
}
/* Don't allow any further call backs. */
pstate->snd_cb->flags = 0;
pstate->snd_cb->priv = NULL;
pstate->snd_cb->event = NULL;
/* Wake up the waiting thread */
nxsem_post(&pstate->snd_sem);
}
return flags;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* 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).
*
* Input 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,
* a negated errno value is retruend. See send() for the complete list
* of return values.
*
****************************************************************************/
ssize_t psock_pkt_send(FAR struct socket *psock, FAR const void *buf,
size_t len)
{
FAR struct net_driver_s *dev;
struct send_s state;
int ret = OK;
/* Verify that the sockfd corresponds to valid, allocated socket */
if (!psock || psock->s_crefs <= 0)
{
return -EBADF;
}
/* Get the device driver that will service this transfer */
dev = pkt_find_device((FAR struct pkt_conn_s *)psock->s_conn);
if (dev == NULL)
{
return -ENODEV;
}
/* Perform the send operation */
/* Initialize the state structure. This is done with the network locked
* because we don't want anything to happen until we are ready.
*/
net_lock();
memset(&state, 0, sizeof(struct send_s));
/* This semaphore is used for signaling and, hence, should not have
* priority inheritance enabled.
*/
nxsem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
nxsem_setprotocol(&state.snd_sem, SEM_PRIO_NONE);
state.snd_sock = psock; /* Socket descriptor to use */
state.snd_buflen = len; /* Number of bytes to send */
state.snd_buffer = buf; /* Buffer to send from */
if (len > 0)
{
FAR struct pkt_conn_s *conn = (FAR struct pkt_conn_s *)psock->s_conn;
/* Allocate resource to receive a callback */
state.snd_cb = pkt_callback_alloc(dev, conn);
if (state.snd_cb)
{
/* Set up the callback in the connection */
state.snd_cb->flags = PKT_POLL;
state.snd_cb->priv = (FAR void *)&state;
state.snd_cb->event = psock_send_eventhandler;
/* Notify the device driver that new TX data is available. */
netdev_txnotify_dev(dev);
/* Wait for the send to complete or an error to occur.
* net_lockedwait will also terminate if a signal is received.
*/
ret = net_lockedwait(&state.snd_sem);
/* Make sure that no further events are processed */
pkt_callback_free(dev, conn, state.snd_cb);
}
}
nxsem_destroy(&state.snd_sem);
net_unlock();
/* Check for a errors, Errors are signalled by negative errno values
* for the send length
*/
if (state.snd_sent < 0)
{
return state.snd_sent;
}
/* If net_lockedwait failed, then we were probably reawakened by a signal.
* In this case, net_lockedwait will have returned negated errno
* appropriately.
*/
if (ret < 0)
{
return ret;
}
/* Return the number of bytes actually sent */
return state.snd_sent;
}
#endif /* CONFIG_NET && CONFIG_NET_PKT */