incubator-nuttx/net/udp/udp_txdrain.c

144 lines
4.6 KiB
C

/****************************************************************************
* net/udp/udp_txdrain.c
*
* Copyright (C) 2019 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>
#include <sys/types.h>
#include <sched.h>
#include <assert.h>
#include <errno.h>
#include <nuttx/semaphore.h>
#include "udp/udp.h"
#if defined(CONFIG_NET_UDP_WRITE_BUFFERS) && defined(CONFIG_NET_UDP_NOTIFIER)
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: txdrain_worker
*
* Description:
* Called with the write buffers have all been sent.
*
* Input Parameters:
* arg - The notifier entry.
*
* Returned Value:
* None.
*
****************************************************************************/
static void txdrain_worker(FAR void *arg)
{
FAR sem_t *waitsem = (FAR sem_t *)arg;
DEBUGASSERT(waitsem != NULL);
/* Then just post the semaphore, waking up tcp_txdrain() */
nxsem_post(waitsem);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: udp_txdrain
*
* Description:
* Wait for all write buffers to be sent (or for a timeout to occur).
*
* Input Parameters:
* psock - An instance of the internal socket structure.
* timeout - The relative time when the timeout will occur
*
* Returned Value:
* Zero (OK) is returned on success; a negated errno value is returned
* on any failure.
*
****************************************************************************/
int udp_txdrain(FAR struct socket *psock, unsigned int timeout)
{
FAR struct udp_conn_s *conn;
sem_t waitsem;
int ret;
DEBUGASSERT(psock != NULL && psock->s_crefs > 0 && psock->s_conn != NULL);
DEBUGASSERT(psock->s_type == SOCK_DGRAM);
conn = (FAR struct udp_conn_s *)psock->s_conn;
/* Initialize the wait semaphore */
nxsem_init(&waitsem, 0, 0);
nxsem_set_protocol(&waitsem, SEM_PRIO_NONE);
/* The following needs to be done with the network stable */
net_lock();
ret = udp_writebuffer_notifier_setup(txdrain_worker, conn, &waitsem);
if (ret > 0)
{
int key = ret;
/* There is pending write data.. wait for it to drain. */
ret = net_timedwait_uninterruptible(&waitsem, timeout);
/* Tear down the notifier (in case we timed out or were canceled) */
if (ret < 0)
{
udp_notifier_teardown(key);
}
}
net_unlock();
nxsem_destroy(&waitsem);
return ret;
}
#endif /* CONFIG_NET_UDP_WRITE_BUFFERS && CONFIG_NET_UDP_NOTIFIER */