/**************************************************************************** * net/pkt/pkt_send.c * * Copyright (C) 2014, 2016-2017 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #if defined(CONFIG_NET) && defined(CONFIG_NET_PKT) #include #include #include #include #include #include #include #include #include #include #include #include #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 */