/****************************************************************************
* net/pkt/pkt_send.c
*
* 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.
*
****************************************************************************/
/****************************************************************************
* 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/clock.h>
#include <nuttx/net/arp.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/pkt.h>
#include "net.h"
#include "uip/uip.h"
#include "pkt/pkt.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/* This structure holds the state of the send operation until it can be
* operated upon from the interrupt level.
*/
struct send_s
{
FAR struct socket *snd_sock; /* Points to the parent socket structure */
FAR struct uip_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
****************************************************************************/
/****************************************************************************
* Function: psock_send_interrupt
****************************************************************************/
static uint16_t psock_send_interrupt(FAR struct uip_driver_s *dev,
FAR void *pvconn,
FAR void *pvpriv, uint16_t flags)
{
FAR struct send_s *pstate = (FAR struct send_s *)pvpriv;
nllvdbg("flags: %04x sent: %d\n", flags, pstate->snd_sent);
if (pstate)
{
/* Check if the outgoing packet is available. If my have been claimed
* by a send interrupt 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 & UIP_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 */
uip_pktsend(dev, pstate->snd_buffer, pstate->snd_buflen);
pstate->snd_sent = pstate->snd_buflen;
}
/* 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 */
sem_post(&pstate->snd_sem);
}
return flags;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: 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:
*
****************************************************************************/
ssize_t psock_pkt_send(FAR struct socket *psock, FAR const void *buf,
size_t len)
{
struct send_s state;
uip_lock_t save;
int err;
int ret = OK;
/* Verify that the sockfd corresponds to valid, allocated socket */
if (!psock || psock->s_crefs <= 0)
{
err = EBADF;
goto errout;
}
/* Set the socket state to sending */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_SEND);
/* Perform the send operation */
/* Initialize the state structure. This is done with interrupts
* disabled because we don't want anything to happen until we
* are ready.
*/
save = uip_lock();
memset(&state, 0, sizeof(struct send_s));
(void)sem_init(&state.snd_sem, 0, 0); /* Doesn't really fail */
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_callbackalloc(conn);
if (state.snd_cb)
{
FAR struct uip_driver_s *dev;
/* Set up the callback in the connection */
state.snd_cb->flags = UIP_POLL;
state.snd_cb->priv = (void*)&state;
state.snd_cb->event = psock_send_interrupt;
/* Notify the device driver of the availability of TX data */
/* TODO better lookup network interface from *psock or *conn */
dev = netdev_findbyname("eth0");
/* Make sure no ARP frame is sent instead of the frame just written */
dev->d_flags |= IFF_NOARP;
/* Notify the device driver that new TX data is available.
* NOTES: This is in essence what netdev_txnotify() does, which
* is not possible to call since it expects a uip_ipaddr_t as
* its single argument to lookup the network interface.
*/
dev->d_txavail(dev);
/* Wait for the send to complete or an error to occure: NOTES: (1)
* uip_lockedwait will also terminate if a signal is received, (2)
* interrupts may be disabled! They will be re-enabled while the
* task sleeps and automatically re-enabled when the task restarts.
*/
ret = uip_lockedwait(&state.snd_sem);
/* Make sure that no further interrupts are processed */
pkt_callbackfree(conn, state.snd_cb);
/* Clear the no-ARP bit in the device flags */
dev->d_flags &= ~IFF_NOARP;
}
}
sem_destroy(&state.snd_sem);
uip_unlock(save);
/* Set the socket state to idle */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE);
/* Check for a errors, Errors are signalled by negative errno values
* for the send length
*/
if (state.snd_sent < 0)
{
err = state.snd_sent;
goto errout;
}
/* If uip_lockedwait failed, then we were probably reawakened by a signal. In
* this case, uip_lockedwait will have set errno appropriately.
*/
if (ret < 0)
{
err = -ret;
goto errout;
}
/* Return the number of bytes actually sent */
return state.snd_sent;
errout:
set_errno(err);
return ERROR;
}
#endif /* CONFIG_NET && CONFIG_NET_PKT */
