/**************************************************************************** * net/tcp/tcp.h * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ #ifndef _NET_TCP_TCP_H #define _NET_TCP_TCP_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #ifdef CONFIG_NET_TCP_NOTIFIER # include #endif #if defined(CONFIG_NET_TCP) && !defined(CONFIG_NET_TCP_NO_STACK) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define NET_TCP_HAVE_STACK 1 /* Allocate a new TCP data callback */ /* These macros allocate and free callback structures used for receiving * notifications of TCP data-related events. */ #define tcp_callback_alloc(conn) \ devif_callback_alloc((conn)->dev, &(conn)->list) #define tcp_callback_free(conn,cb) \ devif_conn_callback_free((conn)->dev, (cb), &(conn)->list) #ifdef CONFIG_NET_TCP_WRITE_BUFFERS /* TCP write buffer access macros */ # define TCP_WBSEQNO(wrb) ((wrb)->wb_seqno) # define TCP_WBPKTLEN(wrb) ((wrb)->wb_iob->io_pktlen) # define TCP_WBSENT(wrb) ((wrb)->wb_sent) # define TCP_WBNRTX(wrb) ((wrb)->wb_nrtx) # define TCP_WBNACK(wrb) ((wrb)->wb_nack) # define TCP_WBIOB(wrb) ((wrb)->wb_iob) # define TCP_WBCOPYOUT(wrb,dest,n) (iob_copyout(dest,(wrb)->wb_iob,(n),0)) # define TCP_WBCOPYIN(wrb,src,n,off) \ (iob_copyin((wrb)->wb_iob,src,(n),(off),true,\ IOBUSER_NET_TCP_WRITEBUFFER)) # define TCP_WBTRYCOPYIN(wrb,src,n,off) \ (iob_trycopyin((wrb)->wb_iob,src,(n),(off),true,\ IOBUSER_NET_TCP_WRITEBUFFER)) # define TCP_WBTRIM(wrb,n) \ do { (wrb)->wb_iob = iob_trimhead((wrb)->wb_iob,(n),\ IOBUSER_NET_TCP_WRITEBUFFER); } while (0) #ifdef CONFIG_DEBUG_FEATURES # define TCP_WBDUMP(msg,wrb,len,offset) \ tcp_wrbuffer_dump(msg,wrb,len,offset) # else # define TCP_WBDUMP(msg,wrb,len,offset) # endif #endif /* 32-bit modular arithmetics for tcp sequence numbers */ #define TCP_SEQ_LT(a, b) ((int32_t)((a) - (b)) < 0) #define TCP_SEQ_GT(a, b) TCP_SEQ_LT(b, a) #define TCP_SEQ_LTE(a, b) (!TCP_SEQ_GT(a, b)) #define TCP_SEQ_GTE(a, b) (!TCP_SEQ_LT(a, b)) #define TCP_SEQ_ADD(a, b) ((uint32_t)((a) + (b))) #define TCP_SEQ_SUB(a, b) ((uint32_t)((a) - (b))) /* The TCP options flags */ #define TCP_WSCALE 0x01U /* Window Scale option enabled */ /**************************************************************************** * Public Type Definitions ****************************************************************************/ struct file; /* Forward reference */ struct sockaddr; /* Forward reference */ struct socket; /* Forward reference */ struct pollfd; /* Forward reference */ /* Representation of a TCP connection. * * The tcp_conn_s structure is used for identifying a connection. All * but one field in the structure are to be considered read-only by an * application. The only exception is the 'private' fields whose purpose * is to let the application store application-specific state (e.g., * file pointers) for the connection. */ struct net_driver_s; /* Forward reference */ struct devif_callback_s; /* Forward reference */ struct tcp_backlog_s; /* Forward reference */ struct tcp_hdr_s; /* Forward reference */ /* This is a container that holds the poll-related information */ struct tcp_poll_s { FAR struct socket *psock; /* Needed to handle loss of connection */ struct pollfd *fds; /* Needed to handle poll events */ FAR struct devif_callback_s *cb; /* Needed to teardown the poll */ }; struct tcp_conn_s { /* Common prologue of all connection structures. */ dq_entry_t node; /* Implements a doubly linked list */ /* TCP callbacks: * * Data transfer events are retained in 'list'. Event handlers in 'list' * are called for events specified in the flags set within struct * devif_callback_s * * When an callback is executed from 'list', the input flags are normally * returned, however, the implementation may set one of the following: * * TCP_CLOSE - Gracefully close the current connection * TCP_ABORT - Abort (reset) the current connection on an error that * prevents TCP_CLOSE from working. * * And/Or set/clear the following: * * TCP_NEWDATA - May be cleared to indicate that the data was consumed * and that no further process of the new data should be * attempted. * TCP_SNDACK - If TCP_NEWDATA is cleared, then TCP_SNDACK may be set to * indicate that an ACK should be included in the response. * (In TCP_NEWDATA is cleared bu TCP_SNDACK is not set, * then dev->d_len should also be cleared). */ FAR struct devif_callback_s *list; /* TCP-specific content follows */ union ip_binding_u u; /* IP address binding */ uint8_t rcvseq[4]; /* The sequence number that we expect to * receive next */ uint8_t sndseq[4]; /* The sequence number that was last sent by us */ uint8_t crefs; /* Reference counts on this instance */ #if defined(CONFIG_NET_IPv4) && defined(CONFIG_NET_IPv6) uint8_t domain; /* IP domain: PF_INET or PF_INET6 */ #endif uint8_t sa; /* Retransmission time-out calculation state * variable */ uint8_t sv; /* Retransmission time-out calculation state * variable */ uint8_t rto; /* Retransmission time-out */ uint8_t tcpstateflags; /* TCP state and flags */ uint8_t timer; /* The retransmission timer (units: half-seconds) */ uint8_t nrtx; /* The number of retransmissions for the last * segment sent */ #ifdef CONFIG_NET_TCP_DELAYED_ACK uint8_t rx_unackseg; /* Number of un-ACKed received segments */ uint8_t rx_acktimer; /* Time since last ACK sent (units: half-seconds) */ #endif uint16_t lport; /* The local TCP port, in network byte order */ uint16_t rport; /* The remoteTCP port, in network byte order */ uint16_t mss; /* Current maximum segment size for the * connection */ uint32_t rcv_adv; /* The right edge of the recv window advertized */ #ifdef CONFIG_NET_TCP_WINDOW_SCALE uint32_t snd_wnd; /* Sequence and acknowledgement numbers of last * window update */ uint8_t snd_scale; /* Sender window scale factor */ uint8_t rcv_scale; /* Receiver windows scale factor */ #else uint16_t snd_wnd; /* Sequence and acknowledgement numbers of last * window update */ #endif #if CONFIG_NET_RECV_BUFSIZE > 0 int32_t rcv_bufs; /* Maximum amount of bytes queued in recv */ #endif #if CONFIG_NET_SEND_BUFSIZE > 0 int32_t snd_bufs; /* Maximum amount of bytes queued in send */ sem_t snd_sem; /* Semaphore signals send completion */ #endif #ifdef CONFIG_NET_TCP_WRITE_BUFFERS uint32_t tx_unacked; /* Number bytes sent but not yet ACKed */ #else uint16_t tx_unacked; /* Number bytes sent but not yet ACKed */ #endif uint16_t flags; /* Flags of TCP-specific options */ /* If the TCP socket is bound to a local address, then this is * a reference to the device that routes traffic on the corresponding * network. */ FAR struct net_driver_s *dev; /* Read-ahead buffering. * * readahead - A singly linked list of type struct iob_s * where the TCP/IP read-ahead data is retained. */ struct iob_s *readahead; /* Read-ahead buffering */ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS /* Write buffering * * write_q - The queue of unsent I/O buffers. The head of this * list may be partially sent. FIFO ordering. * unacked_q - A queue of completely sent, but unacked I/O buffer * chains. Sequence number ordering. */ sq_queue_t write_q; /* Write buffering for segments */ sq_queue_t unacked_q; /* Write buffering for un-ACKed segments */ uint16_t expired; /* Number segments retransmitted but not yet ACKed, * it can only be updated at TCP_ESTABLISHED state */ uint32_t sent; /* The number of bytes sent (ACKed and un-ACKed) */ uint32_t isn; /* Initial sequence number */ uint32_t sndseq_max; /* The sequence number of next not-retransmitted * segment (next greater sndseq) */ #endif #ifdef CONFIG_NET_TCPBACKLOG /* Listen backlog support * * blparent - The backlog parent. If this connection is backlogged, * this field will be non-null and will refer to the TCP connection * structure in which this connection is backlogged. * backlog - The pending connection backlog. If this connection is * configured as a listener with backlog, then this refers to the * struct tcp_backlog_s tear-off structure that manages that backlog. */ FAR struct tcp_conn_s *blparent; FAR struct tcp_backlog_s *backlog; #endif #ifdef CONFIG_NET_TCP_KEEPALIVE /* There fields manage TCP/IP keep-alive. All times are in units of the * system clock tick. */ clock_t keeptime; /* Last time that the TCP socket was known to be * alive (ACK or data received) OR time that the * last probe was sent. */ uint32_t keepidle; /* Elapsed idle time before first probe sent (dsec) */ uint32_t keepintvl; /* Interval between probes (dsec) */ bool keepalive; /* True: KeepAlive enabled; false: disabled */ uint8_t keepcnt; /* Number of retries before the socket is closed */ uint8_t keepretries; /* Number of retries attempted */ #endif /* connevents is a list of callbacks for each socket the uses this * connection (there can be more that one in the event that the the socket * was dup'ed). It is used with the network monitor to handle * asynchronous loss-of-connection events. */ FAR struct devif_callback_s *connevents; /* accept() is called when the TCP logic has created a connection * * accept_private: This is private data that will be available to the * accept() handler when it is invoked with a point to this structure * as an argument. * accept: This is the pointer to the accept handler. */ FAR void *accept_private; int (*accept)(FAR struct tcp_conn_s *listener, FAR struct tcp_conn_s *conn); /* The following is a list of poll structures of threads waiting for * socket events. */ struct tcp_poll_s pollinfo[CONFIG_NET_TCP_NPOLLWAITERS]; }; /* This structure supports TCP write buffering */ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS struct tcp_wrbuffer_s { sq_entry_t wb_node; /* Supports a singly linked list */ uint32_t wb_seqno; /* Sequence number of the write segment */ uint16_t wb_sent; /* Number of bytes sent from the I/O buffer chain */ uint8_t wb_nrtx; /* The number of retransmissions for the last * segment sent */ uint8_t wb_nack; /* The number of ack count */ struct iob_s *wb_iob; /* Head of the I/O buffer chain */ }; #endif /* Support for listen backlog: * * struct tcp_blcontainer_s describes one backlogged connection * struct tcp_backlog_s is a "tear-off" describing all backlog for a * listener connection */ #ifdef CONFIG_NET_TCPBACKLOG struct tcp_blcontainer_s { sq_entry_t bc_node; /* Implements a singly linked list */ FAR struct tcp_conn_s *bc_conn; /* Holds reference to the new connection structure */ }; struct tcp_backlog_s { sq_queue_t bl_free; /* Implements a singly-linked list of free containers */ sq_queue_t bl_pending; /* Implements a singly-linked list of pending connections */ }; #endif /**************************************************************************** * Public Data ****************************************************************************/ #ifdef __cplusplus extern "C" { #endif /**************************************************************************** * Public Function Prototypes ****************************************************************************/ /**************************************************************************** * Name: tcp_initialize * * Description: * Initialize the TCP/IP connection structures. Called only once and only * from the network layer at start-up. * ****************************************************************************/ void tcp_initialize(void); /**************************************************************************** * Name: tcp_alloc * * Description: * Find a free TCP/IP connection structure and allocate it * for use. This is normally something done by the implementation of the * socket() API but is also called from the event processing logic when a * TCP packet is received while "listening" * ****************************************************************************/ FAR struct tcp_conn_s *tcp_alloc(uint8_t domain); /**************************************************************************** * Name: tcp_free * * Description: * Free a connection structure that is no longer in use. This should be * done by the implementation of close() * ****************************************************************************/ void tcp_free(FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_active * * Description: * Find a connection structure that is the appropriate * connection to be used with the provided TCP/IP header * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ FAR struct tcp_conn_s *tcp_active(FAR struct net_driver_s *dev, FAR struct tcp_hdr_s *tcp); /**************************************************************************** * Name: tcp_nextconn * * Description: * Traverse the list of active TCP connections * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ FAR struct tcp_conn_s *tcp_nextconn(FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_local_ipv4_device * * Description: * Select the network driver to use with the IPv4 TCP transaction based * on the locally bound IPv4 address * * Input Parameters: * conn - TCP connection structure. The locally bound address, laddr, * should be set to a non-zero value in this structure. * * Returned Value: * Zero (OK) is returned on success. A negated errno value is returned * on failure. -ENETUNREACH is the only expected error value. * ****************************************************************************/ #ifdef CONFIG_NET_IPv4 int tcp_local_ipv4_device(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_remote_ipv4_device * * Description: * Select the network driver to use with the IPv4 TCP transaction based * on the remotely connected IPv4 address * * Input Parameters: * conn - TCP connection structure. The remotely connected address, raddr, * should be set to a non-zero value in this structure. * * Returned Value: * Zero (OK) is returned on success. A negated errno value is returned * on failure. -ENETUNREACH is the only expected error value. * ****************************************************************************/ #ifdef CONFIG_NET_IPv4 int tcp_remote_ipv4_device(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_local_ipv6_device * * Description: * Select the network driver to use with the IPv6 TCP transaction based * on the locally bound IPv6 address * * Input Parameters: * conn - TCP connection structure. The locally bound address, laddr, * should be set to a non-zero value in this structure. * * Returned Value: * Zero (OK) is returned on success. A negated errno value is returned * on failure. -EHOSTUNREACH is the only expected error value. * ****************************************************************************/ #ifdef CONFIG_NET_IPv6 int tcp_local_ipv6_device(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_remote_ipv6_device * * Description: * Select the network driver to use with the IPv6 TCP transaction based * on the remotely connected IPv6 address * * Input Parameters: * conn - TCP connection structure. The remotely connected address, raddr, * should be set to a non-zero value in this structure. * * Returned Value: * Zero (OK) is returned on success. A negated errno value is returned * on failure. -EHOSTUNREACH is the only expected error value. * ****************************************************************************/ #ifdef CONFIG_NET_IPv6 int tcp_remote_ipv6_device(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_alloc_accept * * Description: * Called when driver processing matches the incoming packet with a * connection in LISTEN. In that case, this function will create a new * connection and initialize it to send a SYNACK in return. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct net_driver_s *dev, FAR struct tcp_hdr_s *tcp); /**************************************************************************** * Name: tcp_bind * * Description: * This function implements the lower level parts of the standard TCP * bind() operation. * * Returned Value: * 0 on success or -EADDRINUSE on failure * * Assumptions: * This function is called from normal user level code. * ****************************************************************************/ int tcp_bind(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr); /**************************************************************************** * Name: tcp_connect * * Description: * This function implements the lower level parts of the standard * TCP connect() operation: It connects to a remote host using TCP. * * This function is used to start a new connection to the specified * port on the specified host. It uses the connection structure that was * allocated by a preceding socket() call. It sets the connection to * the SYN_SENT state and sets the retransmission timer to 0. This will * cause a TCP SYN segment to be sent out the next time this connection * is periodically processed, which usually is done within 0.5 seconds * after the call to tcp_connect(). * * Assumptions: * This function is called from normal user level code. * ****************************************************************************/ int tcp_connect(FAR struct tcp_conn_s *conn, FAR const struct sockaddr *addr); /**************************************************************************** * Name: psock_tcp_connect * * Description: * Perform a TCP connection * * Input Parameters: * psock - A reference to the structure of the socket to be connected * addr - The address of the remote server to connect to * * Returned Value: * None * * Assumptions: * The network is locked * ****************************************************************************/ int psock_tcp_connect(FAR struct socket *psock, FAR const struct sockaddr *addr); /**************************************************************************** * Name: tcp_start_monitor * * Description: * Set up to receive TCP connection state changes for a given socket * * Input Parameters: * psock - The socket of interest * * Returned Value: * On success, tcp_start_monitor returns OK; On any failure, * tcp_start_monitor will return a negated errno value. The only failure * that can occur is if the socket has already been closed and, in this * case, -ENOTCONN is returned. * * Assumptions: * The caller holds the network lock (if not, it will be locked momentarily * by this function). * ****************************************************************************/ int tcp_start_monitor(FAR struct socket *psock); /**************************************************************************** * Name: tcp_stop_monitor * * Description: * Stop monitoring TCP connection changes for a sockets associated with * a given TCP connection structure. * * Input Parameters: * conn - The TCP connection of interest * flags Set of disconnection events * * Returned Value: * None * * Assumptions: * The caller holds the network lock (if not, it will be locked momentarily * by this function). * ****************************************************************************/ void tcp_stop_monitor(FAR struct tcp_conn_s *conn, uint16_t flags); /**************************************************************************** * Name: tcp_close_monitor * * Description: * One socket in a group of dup'ed sockets has been closed. We need to * selectively terminate just those things that are waiting of events * from this specific socket. And also recover any resources that are * committed to monitoring this socket. * * Input Parameters: * psock - The TCP socket structure that is closed * * Returned Value: * None * * Assumptions: * The caller holds the network lock (if not, it will be locked momentarily * by this function). * ****************************************************************************/ void tcp_close_monitor(FAR struct socket *psock); /**************************************************************************** * Name: tcp_lost_connection * * Description: * Called when a loss-of-connection event has been detected by network * event handling logic. Perform operations like tcp_stop_monitor but * (1) explicitly mark this socket and (2) disable further callbacks * the event handler. * * Input Parameters: * psock - The TCP socket structure associated. * cb - devif callback structure * flags - Set of connection events events * * Returned Value: * None * * Assumptions: * The caller holds the network lock (if not, it will be locked momentarily * by this function). * ****************************************************************************/ void tcp_lost_connection(FAR struct socket *psock, FAR struct devif_callback_s *cb, uint16_t flags); /**************************************************************************** * Name: tcp_close * * Description: * Break any current TCP connection * * Input Parameters: * psock - An instance of the internal socket structure. * * Assumptions: * Called from normal user-level logic * ****************************************************************************/ int tcp_close(FAR struct socket *psock); /**************************************************************************** * Name: tcp_ipv4_select * * Description: * Configure to send or receive an TCP IPv4 packet * ****************************************************************************/ #ifdef CONFIG_NET_IPv4 void tcp_ipv4_select(FAR struct net_driver_s *dev); #endif /**************************************************************************** * Name: tcp_ipv6_select * * Description: * Configure to send or receive an TCP IPv6 packet * ****************************************************************************/ #ifdef CONFIG_NET_IPv6 void tcp_ipv6_select(FAR struct net_driver_s *dev); #endif /**************************************************************************** * Name: tcp_setsequence * * Description: * Set the TCP/IP sequence number * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_setsequence(FAR uint8_t *seqno, uint32_t value); /**************************************************************************** * Name: tcp_getsequence * * Description: * Get the TCP/IP sequence number * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ uint32_t tcp_getsequence(FAR uint8_t *seqno); /**************************************************************************** * Name: tcp_addsequence * * Description: * Add the length to get the next TCP sequence number. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ uint32_t tcp_addsequence(FAR uint8_t *seqno, uint16_t len); /**************************************************************************** * Name: tcp_initsequence * * Description: * Set the (initial) the TCP/IP sequence number when a TCP connection is * established. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_initsequence(FAR uint8_t *seqno); /**************************************************************************** * Name: tcp_nextsequence * * Description: * Increment the TCP/IP sequence number * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_nextsequence(void); /**************************************************************************** * Name: tcp_poll * * Description: * Poll a TCP connection structure for availability of TX data * * Input Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP "connection" to poll for TX data * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_poll(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_timer * * Description: * Handle a TCP timer expiration for the provided TCP connection * * Input Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP "connection" to poll for TX data * hsec - The polling interval in halves of a second * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_timer(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, int hsec); /**************************************************************************** * Name: tcp_listen_initialize * * Description: * Setup the listening data structures * * Assumptions: * Called early in the initialization phase while the system is still * single-threaded. * ****************************************************************************/ void tcp_listen_initialize(void); /**************************************************************************** * Name: tcp_findlistener * * Description: * Return the connection listener for connections on this port (if any) * * Assumptions: * The network is locked * ****************************************************************************/ #if defined(CONFIG_NET_IPv4) && defined(CONFIG_NET_IPv6) FAR struct tcp_conn_s *tcp_findlistener(uint16_t portno, uint8_t domain); #else FAR struct tcp_conn_s *tcp_findlistener(uint16_t portno); #endif /**************************************************************************** * Name: tcp_unlisten * * Description: * Stop listening to the port bound to the specified TCP connection * * Assumptions: * Called from normal user code. * ****************************************************************************/ int tcp_unlisten(FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_listen * * Description: * Start listening to the port bound to the specified TCP connection * * Assumptions: * Called from normal user code. * ****************************************************************************/ int tcp_listen(FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_islistener * * Description: * Return true is there is a listener for the specified port * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ #if defined(CONFIG_NET_IPv4) && defined(CONFIG_NET_IPv6) bool tcp_islistener(uint16_t portno, uint8_t domain); #else bool tcp_islistener(uint16_t portno); #endif /**************************************************************************** * Name: tcp_accept_connection * * Description: * Accept the new connection for the specified listening port. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ int tcp_accept_connection(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, uint16_t portno); /**************************************************************************** * Name: tcp_send * * Description: * Setup to send a TCP packet * * Input Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP connection structure holding connection information * flags - flags to apply to the TCP header * len - length of the message * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_send(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, uint16_t flags, uint16_t len); /**************************************************************************** * Name: tcp_sendfile * * Description: * The tcp_sendfile() call may be used only when the INET 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 * flags Send flags * * Returned Value: * On success, returns the number of characters sent. On error, * a negated errno value is returned. See sendfile() for a list * appropriate error return values. * ****************************************************************************/ #ifdef CONFIG_NET_SENDFILE ssize_t tcp_sendfile(FAR struct socket *psock, FAR struct file *infile, FAR off_t *offset, size_t count); #endif /**************************************************************************** * Name: tcp_reset * * Description: * Send a TCP reset (no-data) message * * Input Parameters: * dev - The device driver structure to use in the send operation * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_reset(FAR struct net_driver_s *dev); /**************************************************************************** * Name: tcp_rx_mss * * Description: * Return the MSS to advertize to the peer. * * Input Parameters: * dev - The device driver structure * * Returned Value: * The MSS value. * ****************************************************************************/ uint16_t tcp_rx_mss(FAR struct net_driver_s *dev); /**************************************************************************** * Name: tcp_synack * * Description: * Send the SYN or SYNACK response. * * Input Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP connection structure holding connection information * ack - The ACK response to send * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_synack(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, uint8_t ack); /**************************************************************************** * Name: tcp_appsend * * Description: * Handle application or TCP protocol response. If this function is called * with dev->d_sndlen > 0, then this is an application attempting to send * packet. * * Input Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP connection structure holding connection information * result - App result event sent * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_appsend(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, uint16_t result); /**************************************************************************** * Name: tcp_rexmit * * Description: * Handle application retransmission * * Input Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP connection structure holding connection information * result - App result event sent * * Returned Value: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_rexmit(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, uint16_t result); /**************************************************************************** * Name: tcp_send_txnotify * * Description: * Notify the appropriate device driver that we are have data ready to * be send (TCP) * * Input Parameters: * psock - Socket state structure * conn - The TCP connection structure * * Returned Value: * None * ****************************************************************************/ void tcp_send_txnotify(FAR struct socket *psock, FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_ipv4_input * * Description: * Handle incoming TCP input with IPv4 header * * Input Parameters: * dev - The device driver structure containing the received TCP packet. * * Returned Value: * None * * Assumptions: * Called from the Ethernet driver with the network stack locked * ****************************************************************************/ #ifdef CONFIG_NET_IPv4 void tcp_ipv4_input(FAR struct net_driver_s *dev); #endif /**************************************************************************** * Name: tcp_ipv6_input * * Description: * Handle incoming TCP input with IPv4 header * * Input Parameters: * dev - The device driver structure containing the received TCP packet. * iplen - The size of the IPv6 header. This may be larger than * IPv6_HDRLEN the IPv6 header if IPv6 extension headers are * present. * * Returned Value: * None * * Assumptions: * Called from the Ethernet driver with the network stack locked * ****************************************************************************/ #ifdef CONFIG_NET_IPv6 void tcp_ipv6_input(FAR struct net_driver_s *dev, unsigned int iplen); #endif /**************************************************************************** * Name: tcp_callback * * Description: * Inform the application holding the TCP socket of a change in state. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ uint16_t tcp_callback(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn, uint16_t flags); /**************************************************************************** * Name: tcp_datahandler * * Description: * Handle data that is not accepted by the application. This may be called * either (1) from the data receive logic if it cannot buffer the data, or * (2) from the TCP event logic is there is no listener in place ready to * receive the data. * * Input Parameters: * conn - A pointer to the TCP connection structure * buffer - A pointer to the buffer to be copied to the read-ahead * buffers * buflen - The number of bytes to copy to the read-ahead buffer. * * Returned Value: * The number of bytes actually buffered is returned. This will be either * zero or equal to buflen; partial packets are not buffered. * * Assumptions: * - The caller has checked that TCP_NEWDATA is set in flags and that is no * other handler available to process the incoming data. * - Called from network stack logic with the network stack locked * ****************************************************************************/ uint16_t tcp_datahandler(FAR struct tcp_conn_s *conn, FAR uint8_t *buffer, uint16_t nbytes); /**************************************************************************** * Name: tcp_backlogcreate * * Description: * Called from the listen() logic to setup the backlog as specified in the * the listen arguments. * * Assumptions: * Called from network socket logic. The network may or may not be locked. * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG int tcp_backlogcreate(FAR struct tcp_conn_s *conn, int nblg); #else # define tcp_backlogcreate(c,n) (-ENOSYS) #endif /**************************************************************************** * Name: tcp_backlogdestroy * * Description: * (1) Called from tcp_free() whenever a connection is freed. * (2) Called from tcp_backlogcreate() to destroy any old backlog * * NOTE: This function may re-enter tcp_free when a connection that * is freed that has pending connections. * * Assumptions: * Called from network socket logic with the network stack locked * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG int tcp_backlogdestroy(FAR struct tcp_conn_s *conn); #else # define tcp_backlogdestroy(conn) (-ENOSYS) #endif /**************************************************************************** * Name: tcp_backlogadd * * Description: * Called tcp_listen when a new connection is made with a listener socket * but when there is no accept() in place to receive the connection. This * function adds the new connection to the backlog. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG int tcp_backlogadd(FAR struct tcp_conn_s *conn, FAR struct tcp_conn_s *blconn); #else # define tcp_backlogadd(conn,blconn) (-ENOSYS) #endif /**************************************************************************** * Name: tcp_backlogavailable * * Description: * Called from poll(). Before waiting for a new connection, poll will * call this API to see if there are pending connections in the backlog. * * Assumptions: * The network is locked. * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG bool tcp_backlogavailable(FAR struct tcp_conn_s *conn); #else # define tcp_backlogavailable(c) (false) #endif /**************************************************************************** * Name: tcp_backlogremove * * Description: * Called from accept(). Before waiting for a new connection, accept will * call this API to see if there are pending connections in the backlog. * * Assumptions: * The network is locked. * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG FAR struct tcp_conn_s *tcp_backlogremove(FAR struct tcp_conn_s *conn); #else # define tcp_backlogremove(c) (NULL) #endif /**************************************************************************** * Name: tcp_backlogdelete * * Description: * Called from tcp_free() when a connection is freed that this also * retained in the pending connection list of a listener. We simply need * to remove the defunct connection from the list. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG int tcp_backlogdelete(FAR struct tcp_conn_s *conn, FAR struct tcp_conn_s *blconn); #else # define tcp_backlogdelete(c,b) (-ENOSYS) #endif /**************************************************************************** * Name: tcp_accept * * Description: * This function implements accept() for TCP/IP sockets. See the * description of accept() for further information. * * Input Parameters: * psock The listening TCP socket structure * addr Receives the address of the connecting client * addrlen Input: allocated size of 'addr' * Return: returned size of 'addr' * newconn The new, accepted TCP connection structure * * Returned Value: * Returns zero (OK) on success or a negated errno value on failure. * See the description of accept of the possible errno values in the * description of accept(). * * Assumptions: * Network is locked. * ****************************************************************************/ int psock_tcp_accept(FAR struct socket *psock, FAR struct sockaddr *addr, FAR socklen_t *addrlen, FAR void **newconn); /**************************************************************************** * 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 * buf Buffer to receive data * len Length of buffer * flags Receive flags * from INET address of source (may be NULL) * fromlen The length of the address structure * * 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 void *buf, size_t len, int flags, FAR struct sockaddr *from, FAR socklen_t *fromlen); /**************************************************************************** * Name: psock_tcp_send * * Description: * The psock_tcp_send() call may be used only when the TCP 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 * flags Send flags * * 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_tcp_send(FAR struct socket *psock, FAR const void *buf, size_t len, int flags); /**************************************************************************** * Name: tcp_setsockopt * * Description: * tcp_setsockopt() sets the TCP-protocol option specified by the * 'option' argument to the value pointed to by the 'value' argument for * the socket specified by the 'psock' argument. * * See for the a complete list of values of TCP protocol * options. * * Input Parameters: * psock Socket structure of socket to operate on * option identifies the option to set * value Points to the argument value * value_len The length of the argument value * * Returned Value: * Returns zero (OK) on success. On failure, it returns a negated errno * value to indicate the nature of the error. See psock_setcockopt() for * the list of possible error values. * ****************************************************************************/ #ifdef CONFIG_NET_TCPPROTO_OPTIONS int tcp_setsockopt(FAR struct socket *psock, int option, FAR const void *value, socklen_t value_len); #endif /**************************************************************************** * Name: tcp_getsockopt * * Description: * tcp_getsockopt() retrieves the value for the option specified by the * 'option' argument for the socket specified by the 'psock' argument. If * the size of the option value is greater than 'value_len', the value * stored in the object pointed to by the 'value' argument will be silently * truncated. Otherwise, the length pointed to by the 'value_len' argument * will be modified to indicate the actual length of the 'value'. * * The 'level' argument specifies the protocol level of the option. To * retrieve options at the socket level, specify the level argument as * SOL_SOCKET; to retrieve options at the TCP-protocol level, the level * argument is SOL_TCP. * * See a complete list of values for the socket-level * 'option' argument. Protocol-specific options are are protocol specific * header files (such as netinet/tcp.h for the case of the TCP protocol). * * Input Parameters: * psock Socket structure of the socket to query * level Protocol level to set the option * option identifies the option to get * value Points to the argument value * value_len The length of the argument value * * Returned Value: * Returns zero (OK) on success. On failure, it returns a negated errno * value to indicate the nature of the error. See psock_getsockopt() for * the complete list of appropriate return error codes. * ****************************************************************************/ #ifdef CONFIG_NET_TCPPROTO_OPTIONS int tcp_getsockopt(FAR struct socket *psock, int option, FAR void *value, FAR socklen_t *value_len); #endif /**************************************************************************** * Name: tcp_get_recvwindow * * Description: * Calculate the TCP receive window for the specified device. * * Input Parameters: * dev - The device whose TCP receive window will be updated. * conn - The TCP connection structure holding connection information. * * Returned Value: * The value of the TCP receive window to use. * ****************************************************************************/ uint32_t tcp_get_recvwindow(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: tcp_should_send_recvwindow * * Description: * Determine if we should advertize the new recv window to the peer. * * Input Parameters: * conn - The TCP connection structure holding connection information. * * Returned Value: * If we should send an update. * ****************************************************************************/ bool tcp_should_send_recvwindow(FAR struct tcp_conn_s *conn); /**************************************************************************** * Name: psock_tcp_cansend * * Description: * psock_tcp_cansend() returns a value indicating if a write to the socket * would block. No space in the buffer is actually reserved, so it is * possible that the write may still block if the buffer is filled by * another means. * * Input Parameters: * psock An instance of the internal socket structure. * * Returned Value: * OK * At least one byte of data could be successfully written. * -EWOULDBLOCK * There is no room in the output buffer. * -EBADF * An invalid descriptor was specified. * -ENOTCONN * The socket is not connected. * ****************************************************************************/ int psock_tcp_cansend(FAR struct socket *psock); /**************************************************************************** * Name: tcp_wrbuffer_initialize * * Description: * Initialize the list of free write buffers * * Assumptions: * Called once early initialization. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS void tcp_wrbuffer_initialize(void); #endif /* CONFIG_NET_TCP_WRITE_BUFFERS */ /**************************************************************************** * Name: tcp_wrbuffer_alloc * * Description: * Allocate a TCP write buffer by taking a pre-allocated buffer from * the free list. This function is called from TCP logic when a buffer * of TCP data is about to sent * * Input Parameters: * None * * Assumptions: * Called from user logic with the network locked. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS struct tcp_wrbuffer_s; FAR struct tcp_wrbuffer_s *tcp_wrbuffer_alloc(void); /**************************************************************************** * Name: tcp_wrbuffer_tryalloc * * Description: * Try to allocate a TCP write buffer by taking a pre-allocated buffer from * the free list. This function is called from TCP logic when a buffer * of TCP data is about to be sent if the socket is non-blocking. Returns * immediately if allocation fails. * * Input parameters: * None * * Assumptions: * Called from user logic with the network locked. * ****************************************************************************/ FAR struct tcp_wrbuffer_s *tcp_wrbuffer_tryalloc(void); #endif /* CONFIG_NET_TCP_WRITE_BUFFERS */ /**************************************************************************** * Name: tcp_wrbuffer_release * * Description: * Release a TCP write buffer by returning the buffer to the free list. * This function is called from user logic after it is consumed the * buffered data. * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS void tcp_wrbuffer_release(FAR struct tcp_wrbuffer_s *wrb); #endif /* CONFIG_NET_TCP_WRITE_BUFFERS */ /**************************************************************************** * Name: tcp_wrbuffer_test * * Description: * Check if there is room in the write buffer. Does not reserve any space. * * Assumptions: * None. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS int tcp_wrbuffer_test(void); #endif /* CONFIG_NET_TCP_WRITE_BUFFERS */ /**************************************************************************** * Name: tcp_wrbuffer_dump * * Description: * Dump the contents of a write buffer. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS #ifdef CONFIG_DEBUG_FEATURES void tcp_wrbuffer_dump(FAR const char *msg, FAR struct tcp_wrbuffer_s *wrb, unsigned int len, unsigned int offset); #else # define tcp_wrbuffer_dump(msg,wrb) #endif #endif /* CONFIG_NET_TCP_WRITE_BUFFERS */ /**************************************************************************** * Name: tcp_pollsetup * * Description: * Setup to monitor events on one TCP/IP socket * * Input Parameters: * psock - The TCP/IP socket of interest * fds - The structure describing the events to be monitored, OR NULL if * this is a request to stop monitoring events. * * Returned Value: * 0: Success; Negated errno on failure * ****************************************************************************/ int tcp_pollsetup(FAR struct socket *psock, FAR struct pollfd *fds); /**************************************************************************** * Name: tcp_pollteardown * * Description: * Teardown monitoring of events on an TCP/IP socket * * Input Parameters: * psock - The TCP/IP socket of interest * fds - The structure describing the events to be monitored, OR NULL if * this is a request to stop monitoring events. * * Returned Value: * 0: Success; Negated errno on failure * ****************************************************************************/ int tcp_pollteardown(FAR struct socket *psock, FAR struct pollfd *fds); /**************************************************************************** * Name: tcp_readahead_notifier_setup * * Description: * Set up to perform a callback to the worker function when an TCP data * is added to the read-ahead buffer. The worker function will execute * on the high priority worker thread. * * Input Parameters: * worker - The worker function to execute on the high priority work * queue when data is available in the TCP read-ahead buffer. * conn - The TCP connection where read-ahead data is needed. * arg - A user-defined argument that will be available to the worker * function when it runs. * * Returned Value: * > 0 - The signal notification is in place. The returned value is a * key that may be used later in a call to * tcp_notifier_teardown(). * == 0 - There is already buffered read-ahead data. No signal * notification will be provided. * < 0 - An unexpected error occurred and no signal will be sent. The * returned value is a negated errno value that indicates the * nature of the failure. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_NOTIFIER int tcp_readahead_notifier_setup(worker_t worker, FAR struct tcp_conn_s *conn, FAR void *arg); #endif /**************************************************************************** * Name: tcp_writebuffer_notifier_setup * * Description: * Set up to perform a callback to the worker function when an TCP write * buffer is emptied. The worker function will execute on the high * priority worker thread. * * Input Parameters: * worker - The worker function to execute on the high priority work * queue when all buffer TX data has been sent. * conn - The TCP connection where buffer write data is pending. * arg - A user-defined argument that will be available to the worker * function when it runs. * * Returned Value: * > 0 - The signal notification is in place. The returned value is a * key that may be used later in a call to * tcp_notifier_teardown(). * == 0 - There is already buffered read-ahead data. No signal * notification will be provided. * < 0 - An unexpected error occurred and no signal will be sent. The * returned value is a negated errno value that indicates the * nature of the failure. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_NOTIFIER int tcp_writebuffer_notifier_setup(worker_t worker, FAR struct tcp_conn_s *conn, FAR void *arg); #endif /**************************************************************************** * Name: tcp_disconnect_notifier_setup * * Description: * Set up to perform a callback to the worker function if the TCP * connection is lost. * * Input Parameters: * worker - The worker function to execute on the high priority work * queue when data is available in the TCP read-ahead buffer. * conn - The TCP connection where read-ahead data is needed. * arg - A user-defined argument that will be available to the worker * function when it runs. * * Returned Value: * > 0 - The signal notification is in place. The returned value is a * key that may be used later in a call to * tcp_notifier_teardown(). * == 0 - No connection has been established. * < 0 - An unexpected error occurred and no signal will be sent. The * returned value is a negated errno value that indicates the * nature of the failure. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_NOTIFIER int tcp_disconnect_notifier_setup(worker_t worker, FAR struct tcp_conn_s *conn, FAR void *arg); #endif /**************************************************************************** * Name: tcp_notifier_teardown * * Description: * Eliminate a TCP read-ahead notification previously setup by * tcp_readahead_notifier_setup(). This function should only be called * if the notification should be aborted prior to the notification. The * notification will automatically be torn down after the signal is sent. * * Input Parameters: * key - The key value returned from a previous call to * tcp_readahead_notifier_setup(). * * Returned Value: * Zero (OK) is returned on success; a negated errno value is returned on * any failure. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_NOTIFIER int tcp_notifier_teardown(int key); #endif /**************************************************************************** * Name: tcp_readahead_signal * * Description: * Read-ahead data has been buffered. Signal all threads waiting for * read-ahead data to become available. * * When read-ahead data becomes available, *all* of the workers waiting * for read-ahead data will be executed. If there are multiple workers * waiting for read-ahead data then only the first to execute will get the * data. Others will need to call tcp_readahead_notifier_setup() once * again. * * Input Parameters: * conn - The TCP connection where read-ahead data was just buffered. * * Returned Value: * None. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_NOTIFIER void tcp_readahead_signal(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_writebuffer_signal * * Description: * All buffer Tx data has been sent. Signal all threads waiting for the * write buffers to become empty. * * When write buffer becomes empty, *all* of the workers waiting * for that event data will be executed. If there are multiple workers * waiting for read-ahead data then only the first to execute will get the * data. Others will need to call tcp_writebuffer_notifier_setup() once * again. * * Input Parameters: * conn - The TCP connection where read-ahead data was just buffered. * * Returned Value: * None. * ****************************************************************************/ #if defined(CONFIG_NET_TCP_WRITE_BUFFERS) && defined(CONFIG_NET_TCP_NOTIFIER) void tcp_writebuffer_signal(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_disconnect_signal * * Description: * The TCP connection has been lost. Signal all threads monitoring TCP * state events. * * Input Parameters: * conn - The TCP connection where read-ahead data was just buffered. * * Returned Value: * None. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_NOTIFIER void tcp_disconnect_signal(FAR struct tcp_conn_s *conn); #endif /**************************************************************************** * Name: tcp_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. * ****************************************************************************/ #if defined(CONFIG_NET_TCP_WRITE_BUFFERS) && defined(CONFIG_NET_TCP_NOTIFIER) int tcp_txdrain(FAR struct socket *psock, unsigned int timeout); #else # define tcp_txdrain(conn, timeout) (0) #endif /**************************************************************************** * Name: tcp_ioctl * * Description: * This function performs tcp specific ioctl() operations. * * Parameters: * conn The TCP connection of interest * cmd The ioctl command * arg The argument of the ioctl cmd * arglen The length of 'arg' * ****************************************************************************/ int tcp_ioctl(FAR struct tcp_conn_s *conn, int cmd, FAR void *arg, size_t arglen); /**************************************************************************** * Name: tcp_sendbuffer_notify * * Description: * Notify the send buffer semaphore * * Input Parameters: * conn - The TCP connection of interest * * Assumptions: * Called from user logic with the network locked. * ****************************************************************************/ #if CONFIG_NET_SEND_BUFSIZE > 0 void tcp_sendbuffer_notify(FAR struct tcp_conn_s *conn); #endif /* CONFIG_NET_SEND_BUFSIZE */ #ifdef __cplusplus } #endif #endif /* CONFIG_NET_TCP && !CONFIG_NET_TCP_NO_STACK */ #endif /* _NET_TCP_TCP_H */