/****************************************************************************
* net/udp/udp_sendto.c
*
* Copyright (C) 2007-2009, 2011-2015 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>
#ifdef CONFIG_NET_UDP
#include <sys/types.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/net/net.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/udp.h>
#include "netdev/netdev.h"
#include "devif/devif.h"
#include "arp/arp.h"
#include "socket/socket.h"
#include "udp/udp.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* If both IPv4 and IPv6 support are both enabled, then we will need to build
* in some additional domain selection support.
*/
#if defined(CONFIG_NET_IPv4) && defined(CONFIG_NET_IPv6)
# define NEED_IPDOMAIN_SUPPORT 1
#endif
/* Timeouts on sendto() do not make sense. Each polling cycle from the
* driver is an opportunity to send a packet. If the driver is not polling,
* then the network is not up (and there are no polling cycles to drive
* the timeout).
*
* There is a remote possibility that if there is a lot of other network
* traffic that a UDP sendto could get delayed, but I would not expect this
* generate a timeout.
*/
#undef CONFIG_NET_SENDTO_TIMEOUT
/* If supported, the sendto timeout function would depend on socket options
* and a system clock.
*/
#ifndef CONFIG_NET_SOCKOPTS
# undef CONFIG_NET_SENDTO_TIMEOUT
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct sendto_s
{
#if defined(CONFIG_NET_SENDTO_TIMEOUT) || defined(NEED_IPDOMAIN_SUPPORT)
FAR struct socket *st_sock; /* Points to the parent socket structure */
#endif
#ifdef CONFIG_NET_SENDTO_TIMEOUT
uint32_t st_time; /* Last send time for determining timeout */
#endif
FAR struct devif_callback_s *st_cb; /* Reference to callback instance */
sem_t st_sem; /* Semaphore signals sendto completion */
uint16_t st_buflen; /* Length of send buffer (error if <0) */
const char *st_buffer; /* Pointer to send buffer */
int st_sndlen; /* Result of the send (length sent or negated errno) */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Function: send_timeout
*
* Description:
* Check for send timeout.
*
* Parameters:
* pstate - sendto state structure
*
* Returned Value:
* TRUE:timeout FALSE:no timeout
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef CONFIG_NET_SENDTO_TIMEOUT
static inline int send_timeout(FAR struct sendto_s *pstate)
{
FAR struct socket *psock;
/* Check for a timeout configured via setsockopts(SO_SNDTIMEO).
* If none... we well let the send wait forever.
*/
psock = pstate->st_sock;
if (psock && psock->s_sndtimeo != 0)
{
/* Check if the configured timeout has elapsed */
return net_timeo(pstate->st_time, psock->s_sndtimeo);
}
/* No timeout */
return FALSE;
}
#endif /* CONFIG_NET_SENDTO_TIMEOUT */
/****************************************************************************
* Function: sendto_ipselect
*
* Description:
* If both IPv4 and IPv6 support are enabled, then we will need to select
* which one to use when generating the outgoing packet. If only one
* domain is selected, then the setup is already in place and we need do
* nothing.
*
* Parameters:
* dev - The structure of the network driver that caused the interrupt
* pstate - sendto state structure
*
* Returned Value:
* None
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
#ifdef NEED_IPDOMAIN_SUPPORT
static inline void sendto_ipselect(FAR struct net_driver_s *dev,
FAR struct sendto_s *pstate)
{
FAR struct socket *psock = pstate->st_sock;
DEBUGASSERT(psock);
/* Which domain the the socket support */
if (psock->s_domain == PF_INET)
{
/* Select the IPv4 domain */
udp_ipv4_select(dev);
}
else /* if (psock->s_domain == PF_INET6) */
{
/* Select the IPv6 domain */
DEBUGASSERT(psock->s_domain == PF_INET6);
udp_ipv4_select(dev);
}
}
#endif
/****************************************************************************
* Function: sendto_interrupt
*
* Description:
* This function is called from the interrupt level to perform the actual
* send operation when polled by the lower, device interfacing layer.
*
* Parameters:
* dev The structure of the network driver that caused the interrupt
* conn An instance of the UDP connection structure cast to void *
* pvpriv An instance of struct sendto_s cast to void*
* flags Set of events describing why the callback was invoked
*
* Returned Value:
* Modified value of the input flags
*
* Assumptions:
* Running at the interrupt level
*
****************************************************************************/
static uint16_t sendto_interrupt(FAR struct net_driver_s *dev, FAR void *conn,
FAR void *pvpriv, uint16_t flags)
{
FAR struct sendto_s *pstate = (FAR struct sendto_s *)pvpriv;
nllvdbg("flags: %04x\n", flags);
if (pstate)
{
/* Check if the outgoing packet is available. It may have been claimed
* by a sendto 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 & UDP_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.
*/
#ifdef CONFIG_NET_SENDTO_TIMEOUT
if (send_timeout(pstate))
{
/* Yes.. report the timeout */
nlldbg("SEND timeout\n");
pstate->st_sndlen = -ETIMEDOUT;
}
else
#endif /* CONFIG_NET_SENDTO_TIMEOUT */
{
/* No timeout. Just wait for the next polling cycle */
return flags;
}
}
/* It looks like we are good to send the data */
else
{
#ifdef NEED_IPDOMAIN_SUPPORT
/* If both IPv4 and IPv6 support are enabled, then we will need to
* select which one to use when generating the outgoing packet.
* If only one domain is selected, then the setup is already in
* place and we need do nothing.
*/
sendto_ipselect(dev, pstate);
#endif
/* Copy the user data into d_appdata and send it */
devif_send(dev, pstate->st_buffer, pstate->st_buflen);
pstate->st_sndlen = pstate->st_buflen;
}
/* Don't allow any further call backs. */
pstate->st_cb->flags = 0;
pstate->st_cb->priv = NULL;
pstate->st_cb->event = NULL;
/* Wake up the waiting thread */
sem_post(&pstate->st_sem);
}
return flags;
}
/****************************************************************************
* Function: sendto_txnotify
*
* Description:
* Notify the appropriate device driver that we are have data ready to
* be send (UDP)
*
* Parameters:
* psock - Socket state structure
* conn - The UDP connection structure
*
* Returned Value:
* None
*
****************************************************************************/
static inline void sendto_txnotify(FAR struct socket *psock,
FAR struct udp_conn_s *conn)
{
#ifdef CONFIG_NET_IPv4
#ifdef CONFIG_NET_IPv6
/* If both IPv4 and IPv6 support are enabled, then we will need to select
* the device driver using the appropriate IP domain.
*/
if (psock->s_domain == PF_INET)
#endif
{
/* Notify the device driver that send data is available */
#ifdef CONFIG_NET_MULTILINK
netdev_ipv4_txnotify(conn->u.ipv4.laddr, conn->u.ipv4.raddr);
#else
netdev_ipv4_txnotify(conn->u.ipv4.raddr);
#endif
}
#endif /* CONFIG_NET_IPv4 */
#ifdef CONFIG_NET_IPv6
#ifdef CONFIG_NET_IPv4
else /* if (psock->s_domain == PF_INET6) */
#endif /* CONFIG_NET_IPv4 */
{
/* Notify the device driver that send data is available */
DEBUGASSERT(psock->s_domain == PF_INET6);
#ifdef CONFIG_NET_MULTILINK
netdev_ipv6_txnotify(conn->u.ipv6.laddr, conn->u.ipv6.raddr);
#else
netdev_ipv6_txnotify(conn->u.ipv6.raddr);
#endif
}
#endif /* CONFIG_NET_IPv6 */
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: psock_udp_sendto
*
* Description:
* This function implements the UDP-specific logic of the standard
* sendto() socket operation.
*
* Input Parameters:
* psock A pointer to a NuttX-specific, internal socket structure
* buf Data to send
* len Length of data to send
* flags Send flags
* to Address of recipient
* tolen The length of the address structure
*
* NOTE: All input parameters were verified by sendto() before this
* function was called.
*
* Returned Value:
* On success, returns the number of characters sent. On error,
* a negated errno value is returned. See the description in
* net/socket/sendto.c for the list of appropriate return value.
*
****************************************************************************/
ssize_t psock_udp_sendto(FAR struct socket *psock, FAR const void *buf,
size_t len, int flags, FAR const struct sockaddr *to,
socklen_t tolen)
{
FAR struct udp_conn_s *conn;
struct sendto_s state;
net_lock_t save;
int ret;
#ifdef CONFIG_NET_ARP_SEND
FAR const struct sockaddr_in *into;
/* Make sure that the IP address mapping is in the ARP table */
into = (FAR const struct sockaddr_in *)to;
ret = arp_send(into->sin_addr.s_addr);
if (ret < 0)
{
ndbg("ERROR: Not reachable\n");
return -ENETUNREACH;
}
#endif
/* Set the socket state to sending */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_SEND);
/* Initialize the state structure. This is done with interrupts
* disabled because we don't want anything to happen until we
* are ready.
*/
save = net_lock();
memset(&state, 0, sizeof(struct sendto_s));
sem_init(&state.st_sem, 0, 0);
state.st_buflen = len;
state.st_buffer = buf;
#if defined(CONFIG_NET_SENDTO_TIMEOUT) || defined(NEED_IPDOMAIN_SUPPORT)
/* Save the reference to the socket structure if it will be needed for
* asynchronous processing.
*/
state.st_sock = psock;
#endif
#ifdef CONFIG_NET_SENDTO_TIMEOUT
/* Set the initial time for calculating timeouts */
state.st_time = clock_systimer();
#endif
/* Setup the UDP socket */
conn = (FAR struct udp_conn_s *)psock->s_conn;
ret = udp_connect(conn, to);
if (ret < 0)
{
net_unlock(save);
return ret;
}
/* Set up the callback in the connection */
state.st_cb = udp_callback_alloc(conn);
if (state.st_cb)
{
state.st_cb->flags = UDP_POLL;
state.st_cb->priv = (void*)&state;
state.st_cb->event = sendto_interrupt;
/* Notify the device driver of the availability of TX data */
sendto_txnotify(psock, conn);
/* Wait for either the receive to complete or for an error/timeout to occur.
* NOTES: (1) net_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.
*/
net_lockedwait(&state.st_sem);
/* Make sure that no further interrupts are processed */
udp_callback_free(conn, state.st_cb);
}
net_unlock(save);
sem_destroy(&state.st_sem);
/* Set the socket state to idle */
psock->s_flags = _SS_SETSTATE(psock->s_flags, _SF_IDLE);
/* Return the result of the sendto() operation */
return state.st_sndlen;
}
#endif /* CONFIG_NET_UDP */
