b5753d06f2
Signed-off-by: daichuan <daichuan@xiaomi.com>
813 lines
24 KiB
C
813 lines
24 KiB
C
/****************************************************************************
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* net/tcp/tcp_recvfrom.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#ifdef CONFIG_NET_TCP
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#include <string.h>
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#include <errno.h>
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#include <debug.h>
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#include <assert.h>
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#include <nuttx/semaphore.h>
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#include <nuttx/net/net.h>
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#include <nuttx/mm/iob.h>
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#include <nuttx/net/netdev.h>
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#include <nuttx/net/ip.h>
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#include <nuttx/net/tcp.h>
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#include "netdev/netdev.h"
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#include "devif/devif.h"
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#include "tcp/tcp.h"
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#include "socket/socket.h"
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/****************************************************************************
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* Private Types
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****************************************************************************/
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struct tcp_recvfrom_s
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{
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FAR struct tcp_conn_s *ir_conn; /* Connection associated with the socket */
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FAR struct devif_callback_s *ir_cb; /* Reference to callback instance */
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sem_t ir_sem; /* Semaphore signals recv completion */
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size_t ir_buflen; /* Length of receive buffer */
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uint8_t *ir_buffer; /* Pointer to receive buffer */
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FAR struct sockaddr *ir_from; /* Address of sender */
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FAR socklen_t *ir_fromlen; /* Number of bytes allocated for address of sender */
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ssize_t ir_recvlen; /* The received length */
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int ir_result; /* Success:OK, failure:negated errno */
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int ir_flags; /* Flags on received message. */
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};
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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/****************************************************************************
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* Name: tcp_update_recvlen
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*
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* Description:
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* Update information about space available for new data and update size
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* of data in buffer.
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*
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* Input Parameters:
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* pstate recvfrom state structure
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* recvlen size of new data appended to buffer
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*
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* Returned Value:
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* None
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*
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****************************************************************************/
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static inline void tcp_update_recvlen(FAR struct tcp_recvfrom_s *pstate,
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size_t recvlen)
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{
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if (pstate->ir_recvlen < 0)
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{
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pstate->ir_recvlen = 0;
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}
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pstate->ir_recvlen += recvlen;
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pstate->ir_buffer += recvlen;
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pstate->ir_buflen -= recvlen;
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}
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/****************************************************************************
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* Name: tcp_recvfrom_newdata
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*
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* Description:
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* Copy the read data from the packet
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*
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* Input Parameters:
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* dev The structure of the network driver that generated the event.
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* pstate recvfrom state structure
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*
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* Returned Value:
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* The number of bytes taken from the packet.
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*
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* Assumptions:
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* The network is locked.
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*
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****************************************************************************/
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static size_t tcp_recvfrom_newdata(FAR struct net_driver_s *dev,
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FAR struct tcp_recvfrom_s *pstate)
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{
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unsigned int offset;
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size_t recvlen;
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/* Get the length of the data to return */
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if (dev->d_len > pstate->ir_buflen)
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{
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recvlen = pstate->ir_buflen;
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}
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else
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{
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recvlen = dev->d_len;
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}
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/* Copy the new appdata into the user buffer */
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offset = (dev->d_appdata - dev->d_iob->io_data) - dev->d_iob->io_offset;
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recvlen = iob_copyout(pstate->ir_buffer, dev->d_iob, recvlen, offset);
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/* Trim the copied buffers */
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dev->d_iob = iob_trimhead(dev->d_iob,
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pstate->ir_flags & MSG_PEEK ? offset : recvlen + offset);
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ninfo("Received %d bytes (of %d)\n", (int)recvlen, (int)dev->d_len);
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/* Update the accumulated size of the data read */
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tcp_update_recvlen(pstate, recvlen);
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return pstate->ir_flags & MSG_PEEK ? 0: recvlen;
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}
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/****************************************************************************
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* Name: tcp_newdata
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*
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* Description:
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* Copy the read data from the packet
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*
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* Input Parameters:
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* dev The structure of the network driver that generated the event
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* pstate recvfrom state structure
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*
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* Returned Value:
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* None.
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*
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* Assumptions:
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* The network is locked.
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*
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****************************************************************************/
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static inline uint16_t tcp_newdata(FAR struct net_driver_s *dev,
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FAR struct tcp_recvfrom_s *pstate,
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uint16_t flags)
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{
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FAR struct tcp_conn_s *conn = pstate->ir_conn;
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/* Take as much data from the packet as we can */
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size_t recvlen = tcp_recvfrom_newdata(dev, pstate);
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/* If there is more data left in the packet that we could not buffer, then
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* add it to the read-ahead buffers.
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*/
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if (recvlen < dev->d_len)
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{
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uint16_t nsaved;
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uint16_t buflen = dev->d_len - recvlen;
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nsaved = tcp_datahandler(dev, conn, 0);
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if (nsaved < buflen)
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{
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nwarn("WARNING: packet data not fully saved "
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"(%d/%u/%zu/%u bytes)\n",
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buflen - nsaved,
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(unsigned int)nsaved,
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recvlen,
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(unsigned int)dev->d_len);
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}
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recvlen += nsaved;
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}
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else
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{
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netdev_iob_release(dev);
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}
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if (recvlen < dev->d_len)
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{
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/* Clear the TCP_CLOSE because we effectively dropped the FIN as well.
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*/
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flags &= ~TCP_CLOSE;
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}
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net_incr32(conn->rcvseq, recvlen);
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/* Indicate no data in the buffer */
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dev->d_len = 0;
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return flags;
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}
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/****************************************************************************
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* Name: tcp_readahead
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*
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* Description:
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* Copy the read-ahead data from the packet
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*
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* Input Parameters:
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* pstate recvfrom state structure
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*
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* Returned Value:
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* None
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*
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* Assumptions:
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* The network is locked.
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*
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****************************************************************************/
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static inline void tcp_readahead(struct tcp_recvfrom_s *pstate)
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{
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FAR struct tcp_conn_s *conn = pstate->ir_conn;
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FAR struct iob_s *iob;
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int recvlen;
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/* Check there is any TCP data already buffered in a read-ahead
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* buffer.
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*/
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while ((iob = conn->readahead) != NULL &&
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pstate->ir_buflen > 0)
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{
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DEBUGASSERT(iob->io_pktlen > 0);
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/* Transfer that buffered data from the I/O buffer chain into
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* the user buffer.
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*/
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recvlen = iob_copyout(pstate->ir_buffer, iob, pstate->ir_buflen, 0);
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ninfo("Received %d bytes (of %d)\n", recvlen, iob->io_pktlen);
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/* Update the accumulated size of the data read */
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tcp_update_recvlen(pstate, recvlen);
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/* If it is in read-ahead mode,
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* exit directly to avoid iob being released
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*/
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if (pstate->ir_flags & MSG_PEEK)
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{
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break;
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}
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/* If we took all of the data from the I/O buffer chain is empty, then
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* release it. If there is still data available in the I/O buffer
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* chain, then just trim the data that we have taken from the
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* beginning of the I/O buffer chain.
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*/
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if (recvlen >= iob->io_pktlen)
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{
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/* Free free the I/O buffer chain */
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iob_free_chain(iob);
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conn->readahead = NULL;
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}
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else
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{
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/* The bytes that we have received from the head of the I/O
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* buffer chain.
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*/
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conn->readahead = iob_trimhead(iob, recvlen);
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}
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}
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}
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/****************************************************************************
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* Name: tcp_sender
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*
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* Description:
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* Getting the sender's address from the UDP packet
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*
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* Input Parameters:
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* dev - The device driver data structure
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* pstate - the recvfrom state structure
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*
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* Returned Value:
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* None
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*
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* Assumptions:
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* The network is locked
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*
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****************************************************************************/
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static inline void tcp_sender(FAR struct net_driver_s *dev,
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FAR struct tcp_recvfrom_s *pstate)
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{
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/* Get the family from the packet type, IP address from the IP header, and
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* the port number from the TCP header.
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*/
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#ifdef CONFIG_NET_IPv6
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#ifdef CONFIG_NET_IPv4
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if (IFF_IS_IPv6(dev->d_flags))
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#endif
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{
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FAR struct sockaddr_in6 *infrom =
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(FAR struct sockaddr_in6 *)pstate->ir_from;
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if (infrom)
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{
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FAR struct tcp_hdr_s *tcp = TCPIPv6BUF;
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FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
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infrom->sin6_family = AF_INET6;
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infrom->sin6_port = tcp->srcport;
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net_ipv6addr_copy(infrom->sin6_addr.s6_addr, ipv6->srcipaddr);
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}
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}
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#endif /* CONFIG_NET_IPv6 */
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#ifdef CONFIG_NET_IPv4
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#ifdef CONFIG_NET_IPv6
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else
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#endif
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{
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FAR struct sockaddr_in *infrom =
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(FAR struct sockaddr_in *)pstate->ir_from;
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if (infrom)
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{
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FAR struct tcp_hdr_s *tcp = TCPIPv4BUF;
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FAR struct ipv4_hdr_s *ipv4 = IPv4BUF;
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infrom->sin_family = AF_INET;
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infrom->sin_port = tcp->srcport;
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net_ipv4addr_copy(infrom->sin_addr.s_addr,
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net_ip4addr_conv32(ipv4->srcipaddr));
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memset(infrom->sin_zero, 0, sizeof(infrom->sin_zero));
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}
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}
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#endif /* CONFIG_NET_IPv4 */
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}
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/****************************************************************************
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* Name: tcp_recvhandler
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*
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* Description:
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* This function is called with the network locked to perform the actual
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* TCP receive operation via by the lower, device interfacing layer.
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*
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* Input Parameters:
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* dev The structure of the network driver that generated the event.
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* pvpriv An instance of struct tcp_recvfrom_s cast to void*
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* flags Set of events describing why the callback was invoked
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*
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* Returned Value:
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* None
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*
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* Assumptions:
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* The network is locked.
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*
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****************************************************************************/
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static uint16_t tcp_recvhandler(FAR struct net_driver_s *dev,
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FAR void *pvpriv, uint16_t flags)
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{
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FAR struct tcp_recvfrom_s *pstate = pvpriv;
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ninfo("flags: %04x\n", flags);
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/* 'priv' might be null in some race conditions (?) */
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if (pstate)
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{
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/* If new data is available, then complete the read action. */
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if ((flags & TCP_NEWDATA) != 0)
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{
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/* Save the sender's address in the caller's 'from' location */
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tcp_sender(dev, pstate);
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/* Copy the data from the packet (saving any unused bytes from the
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* packet in the read-ahead buffer).
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*/
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flags = tcp_newdata(dev, pstate, flags);
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/* Indicate that the data has been consumed and that an ACK
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* should be sent.
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*/
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flags = (flags & ~TCP_NEWDATA) | TCP_SNDACK;
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/* Check for transfer complete. We will consider the
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* TCP/IP transfer complete as soon as any data has been received.
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* This is safe because if any additional data is received, it
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* will be retained in the TCP/IP read-ahead buffer until the
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* next receive is performed.
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*/
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if ((pstate->ir_recvlen > 0 &&
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(pstate->ir_cb->flags & TCP_WAITALL) == 0) ||
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pstate->ir_buflen == 0)
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{
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ninfo("TCP resume\n");
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/* The TCP receive buffer is non-empty. Return now and don't
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* allow any further TCP call backs.
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*/
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pstate->ir_cb->flags = 0;
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pstate->ir_cb->priv = NULL;
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pstate->ir_cb->event = NULL;
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/* Wake up the waiting thread, returning the number of bytes
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* actually read.
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*/
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nxsem_post(&pstate->ir_sem);
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}
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}
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/* Check for a loss of connection.
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*
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* TCP_DISCONN_EVENTS:
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* TCP_CLOSE: The remote host has closed the connection
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* TCP_ABORT: The remote host has aborted the connection
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* TCP_TIMEDOUT: Connection aborted due to too many retransmissions.
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* NETDEV_DOWN: The network device went down
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*/
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else if ((flags & TCP_DISCONN_EVENTS) != 0)
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{
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FAR struct tcp_conn_s *conn = pstate->ir_conn;
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nwarn("WARNING: Lost connection\n");
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/* We could get here recursively through the callback actions of
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* tcp_lost_connection(). So don't repeat that action if we have
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* already been disconnected.
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*/
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DEBUGASSERT(conn != NULL);
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if (_SS_ISCONNECTED(conn->sconn.s_flags))
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{
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/* Handle loss-of-connection event */
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tcp_lost_connection(conn, pstate->ir_cb, flags);
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}
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/* Check if the peer gracefully closed the connection. */
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if ((flags & TCP_CLOSE) != 0)
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{
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/* This case should always return success (zero)! The value of
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* ir_recvlen, if zero, will indicate that the connection was
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* gracefully closed.
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*/
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pstate->ir_result = 0;
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}
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else
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{
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pstate->ir_result = -ENOTCONN;
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}
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/* Wake up the waiting thread */
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nxsem_post(&pstate->ir_sem);
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}
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}
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return flags;
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}
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/****************************************************************************
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* Name: tcp_recvfrom_initialize
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*
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* Description:
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* Initialize the state structure
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*
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* Input Parameters:
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* conn The TCP connection of interest
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* buf Buffer to receive data
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* len Length of buffer
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* pstate A pointer to the state structure to be initialized
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*
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* Returned Value:
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* None
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*
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* Assumptions:
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*
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****************************************************************************/
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static void tcp_recvfrom_initialize(FAR struct tcp_conn_s *conn,
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FAR void *buf, size_t len,
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FAR struct sockaddr *infrom,
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FAR socklen_t *fromlen,
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FAR struct tcp_recvfrom_s *pstate,
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int flags)
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{
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/* Initialize the state structure. */
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memset(pstate, 0, sizeof(struct tcp_recvfrom_s));
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nxsem_init(&pstate->ir_sem, 0, 0); /* Doesn't really fail */
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pstate->ir_buflen = len;
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pstate->ir_buffer = buf;
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pstate->ir_from = infrom;
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pstate->ir_fromlen = fromlen;
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pstate->ir_flags = flags;
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/* Set up the start time for the timeout */
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pstate->ir_conn = conn;
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}
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/* The only un-initialization that has to be performed is destroying the
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* semaphore.
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*/
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#define tcp_recvfrom_uninitialize(s) nxsem_destroy(&(s)->ir_sem)
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/****************************************************************************
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* Name: tcp_recvfrom_result
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*
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* Description:
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* Evaluate the result of the recv operations
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*
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* Input Parameters:
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* result The result of the net_sem_timedwait operation
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* (may indicate EINTR)
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* pstate A pointer to the state structure to be initialized
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*
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* Returned Value:
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* The result of the recv operation with errno set appropriately
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*
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* Assumptions:
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*
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****************************************************************************/
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static ssize_t tcp_recvfrom_result(int result, struct tcp_recvfrom_s *pstate)
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{
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/* Check if any data were received. If so, then return their length and
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* ignore any error codes.
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*/
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if (pstate->ir_recvlen > 0)
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{
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return pstate->ir_recvlen;
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}
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|
|
/* If no data were received, return the error code instead. The event
|
|
* handler error is prioritized over any previous error.
|
|
*/
|
|
|
|
return (pstate->ir_result < 0) ? pstate->ir_result : result;
|
|
}
|
|
|
|
/****************************************************************************
|
|
* Name: tcp_notify_recvcpu
|
|
*
|
|
* Description:
|
|
* This function will check current cpu id with conn->rcvcpu, if
|
|
* not same, then use netdev_notify_recvcpu to notify the new cpu id
|
|
*
|
|
* Input Parameters:
|
|
* conn - The TCP connection of interest
|
|
*
|
|
* Returned Value:
|
|
* None
|
|
*
|
|
* Assumptions:
|
|
* conn is not NULL.
|
|
*
|
|
****************************************************************************/
|
|
|
|
#ifdef CONFIG_NETDEV_RSS
|
|
static void tcp_notify_recvcpu(FAR struct tcp_conn_s *conn)
|
|
{
|
|
int cpu = up_cpu_index();
|
|
|
|
if (cpu != conn->rcvcpu)
|
|
{
|
|
conn->rcvcpu = cpu;
|
|
|
|
if (conn->domain == PF_INET)
|
|
{
|
|
netdev_notify_recvcpu(conn->dev, cpu, conn->domain,
|
|
&(conn->u.ipv4.laddr), conn->lport,
|
|
&(conn->u.ipv4.raddr), conn->rport);
|
|
}
|
|
else
|
|
{
|
|
netdev_notify_recvcpu(conn->dev, cpu, conn->domain,
|
|
&(conn->u.ipv6.laddr), conn->lport,
|
|
&(conn->u.ipv6.raddr), conn->rport);
|
|
}
|
|
}
|
|
}
|
|
#else
|
|
# define tcp_notify_recvcpu(c)
|
|
#endif /* CONFIG_NETDEV_RSS */
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: psock_tcp_recvfrom
|
|
*
|
|
* Description:
|
|
* Perform the recvfrom operation for a TCP/IP SOCK_STREAM
|
|
*
|
|
* Input Parameters:
|
|
* psock Pointer to the socket structure for the SOCK_DRAM socket
|
|
* msg Receive info and buffer for receive data
|
|
* flags Receive flags
|
|
*
|
|
* Returned Value:
|
|
* On success, returns the number of characters received. On error,
|
|
* -errno is returned (see recvfrom for list of errnos).
|
|
*
|
|
* Assumptions:
|
|
*
|
|
****************************************************************************/
|
|
|
|
ssize_t psock_tcp_recvfrom(FAR struct socket *psock, FAR struct msghdr *msg,
|
|
int flags)
|
|
{
|
|
FAR struct sockaddr *from = msg->msg_name;
|
|
FAR socklen_t *fromlen = &msg->msg_namelen;
|
|
FAR void *buf = msg->msg_iov->iov_base;
|
|
size_t len = msg->msg_iov->iov_len;
|
|
struct tcp_recvfrom_s state;
|
|
FAR struct tcp_conn_s *conn;
|
|
int ret;
|
|
|
|
net_lock();
|
|
|
|
conn = psock->s_conn;
|
|
|
|
/* Initialize the state structure. This is done with the network locked
|
|
* because we don't want anything to happen until we are ready.
|
|
*/
|
|
|
|
tcp_recvfrom_initialize(conn, buf, len, from, fromlen, &state, flags);
|
|
|
|
/* Handle any any TCP data already buffered in a read-ahead buffer. NOTE
|
|
* that there may be read-ahead data to be retrieved even after the
|
|
* socket has been disconnected.
|
|
*/
|
|
|
|
tcp_readahead(&state);
|
|
|
|
/* The default return value is the number of bytes that we just copied
|
|
* into the user buffer. We will return this if the socket has become
|
|
* disconnected or if the user request was completely satisfied with
|
|
* data from the readahead buffers.
|
|
*/
|
|
|
|
ret = state.ir_recvlen;
|
|
|
|
/* Verify that the SOCK_STREAM has been and still is connected */
|
|
|
|
if (!_SS_ISCONNECTED(conn->sconn.s_flags))
|
|
{
|
|
/* Was any data transferred from the readahead buffer after we were
|
|
* disconnected? If so, then return the number of bytes received. We
|
|
* will wait to return end disconnection indications the next time that
|
|
* recvfrom() is called.
|
|
*
|
|
* If no data was received (i.e., ret == 0 -- it will not be
|
|
* negative) and the connection was gracefully closed by the remote
|
|
* peer, then return success. If ir_recvlen is zero, the caller of
|
|
* recvfrom() will get an end-of-file indication.
|
|
*/
|
|
|
|
if (ret <= 0 && !_SS_ISCLOSED(conn->sconn.s_flags))
|
|
{
|
|
/* Nothing was previously received from the read-ahead buffers.
|
|
* The SOCK_STREAM must be (re-)connected in order to receive any
|
|
* additional data.
|
|
*/
|
|
|
|
ret = -ENOTCONN;
|
|
}
|
|
}
|
|
|
|
/* In general, this implementation will not support non-blocking socket
|
|
* operations... except in a few cases: Here for TCP receive with read-
|
|
* ahead enabled. If this socket is configured as non-blocking then
|
|
* return EAGAIN if no data was obtained from the read-ahead buffers.
|
|
*/
|
|
|
|
else if (_SS_ISNONBLOCK(conn->sconn.s_flags) ||
|
|
(flags & MSG_DONTWAIT) != 0)
|
|
{
|
|
/* Return the number of bytes read from the read-ahead buffer if
|
|
* something was received (already in 'ret'); EAGAIN if not.
|
|
*/
|
|
|
|
if (ret <= 0)
|
|
{
|
|
/* Nothing was received */
|
|
|
|
ret = -EAGAIN;
|
|
}
|
|
}
|
|
|
|
/* It is okay to block if we need to. If there is space to receive
|
|
* anything more, then we will wait to receive the data. Otherwise return
|
|
* the number of bytes read from the read-ahead buffer (already in 'ret').
|
|
*/
|
|
|
|
else
|
|
|
|
/* We get here when we we decide that we need to setup the wait for
|
|
* incoming TCP/IP data. Just a few more conditions to check:
|
|
*
|
|
* 1) Make sure that there is buffer space to receive additional data
|
|
* (state.ir_buflen > 0). This could be zero, for example, we filled
|
|
* the user buffer with data from the read-ahead buffers. And
|
|
* 2) then we not want to wait if we already obtained some data from the
|
|
* read-ahead buffer. In that case, return now with what we have (don't
|
|
* want for more because there may be no timeout).
|
|
* 3) If however MSG_WAITALL flag is set, block here till all requested
|
|
* data are received (or there is a timeout / error).
|
|
*/
|
|
|
|
if (((flags & MSG_WAITALL) != 0 || state.ir_recvlen == 0) &&
|
|
state.ir_buflen > 0)
|
|
{
|
|
/* Set up the callback in the connection */
|
|
|
|
state.ir_cb = tcp_callback_alloc(conn);
|
|
if (state.ir_cb)
|
|
{
|
|
state.ir_cb->flags = (TCP_NEWDATA | TCP_DISCONN_EVENTS);
|
|
state.ir_cb->flags |= (flags & MSG_WAITALL) ? TCP_WAITALL : 0;
|
|
state.ir_cb->priv = (FAR void *)&state;
|
|
state.ir_cb->event = tcp_recvhandler;
|
|
|
|
/* Wait for either the receive to complete or for an error/timeout
|
|
* to occur. net_sem_timedwait will also terminate if a signal is
|
|
* received.
|
|
*/
|
|
|
|
ret = net_sem_timedwait(&state.ir_sem,
|
|
_SO_TIMEOUT(conn->sconn.s_rcvtimeo));
|
|
if (ret == -ETIMEDOUT)
|
|
{
|
|
ret = -EAGAIN;
|
|
}
|
|
|
|
/* Make sure that no further events are processed */
|
|
|
|
tcp_callback_free(conn, state.ir_cb);
|
|
ret = tcp_recvfrom_result(ret, &state);
|
|
}
|
|
else if (ret <= 0)
|
|
{
|
|
ret = -EBUSY;
|
|
}
|
|
}
|
|
|
|
/* Receive additional data from read-ahead buffer, send the ACK timely.
|
|
*
|
|
* Revisit: Because IOBs are system-wide resources, consuming the read
|
|
* ahead buffer would update recv window of all connections in the system,
|
|
* not only this particular connection.
|
|
*/
|
|
|
|
if (tcp_should_send_recvwindow(conn))
|
|
{
|
|
netdev_txnotify_dev(conn->dev);
|
|
}
|
|
|
|
tcp_notify_recvcpu(conn);
|
|
|
|
net_unlock();
|
|
tcp_recvfrom_uninitialize(&state);
|
|
return (ssize_t)ret;
|
|
}
|
|
|
|
#endif /* CONFIG_NET_TCP */
|