/**************************************************************************** * net/tcp/tcp.h * * Copyright (C) 2014-2015 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ #ifndef _NET_TCP_TCP_H #define _NET_TCP_TCP_H /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #ifdef CONFIG_NET_TCP /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Conditions for support TCP poll/select operations */ #if !defined(CONFIG_DISABLE_POLL) && CONFIG_NSOCKET_DESCRIPTORS > 0 && \ defined(CONFIG_NET_TCP_READAHEAD) # define HAVE_TCP_POLL #endif /* Allocate a new TCP data callback */ #define tcp_callback_alloc(conn) devif_callback_alloc(NULL, &conn->list) #define tcp_callback_free(conn,cb) devif_callback_free(NULL, cb, &conn->list) /* Get the current maximum segment size that can be sent on the current * TCP connection. */ #define tcp_mss(conn) ((conn)->mss) #ifdef CONFIG_NET_TCP_WRITE_BUFFERS /* TCP write buffer access macros */ # define WRB_SEQNO(wrb) ((wrb)->wb_seqno) # define WRB_PKTLEN(wrb) ((wrb)->wb_iob->io_pktlen) # define WRB_SENT(wrb) ((wrb)->wb_sent) # define WRB_NRTX(wrb) ((wrb)->wb_nrtx) # define WRB_IOB(wrb) ((wrb)->wb_iob) # define WRB_COPYOUT(wrb,dest,n) (iob_copyout(dest,(wrb)->wb_iob,(n),0)) # define WRB_COPYIN(wrb,src,n) (iob_copyin((wrb)->wb_iob,src,(n),0,false)) # define WRB_TRIM(wrb,n) \ do { (wrb)->wb_iob = iob_trimhead((wrb)->wb_iob,(n)); } while (0) #ifdef CONFIG_DEBUG # define WRB_DUMP(msg,wrb,len,offset) \ tcp_wrbuffer_dump(msg,wrb,len,offset) #else # define WRB_DUMP(msg,wrb,len,offset) #endif #endif /**************************************************************************** * Public Type Definitions ****************************************************************************/ /* 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 */ struct tcp_conn_s { dq_entry_t node; /* Implements a doubly linked list */ 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 */ 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 */ uint16_t winsize; /* Current window size of the connection */ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS uint32_t unacked; /* Number bytes sent but not yet ACKed */ #else uint16_t unacked; /* Number bytes sent but not yet ACKed */ #endif /* Read-ahead buffering. * * readahead - A singly linked list of type struct iob_qentry_s * where the TCP/IP read-ahead data is retained. */ #ifdef CONFIG_NET_TCP_READAHEAD struct iob_queue_s readahead; /* Read-ahead buffering */ #endif /* 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. */ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS 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 */ #endif /* 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. */ #ifdef CONFIG_NET_TCPBACKLOG FAR struct tcp_conn_s *blparent; FAR struct tcp_backlog_s *backlog; #endif /* Application 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; /* accept() is called when the TCP logic has created a connection */ FAR void *accept_private; int (*accept)(FAR struct tcp_conn_s *listener, FAR struct tcp_conn_s *conn); /* connection_event() is called on any of the subset of connection-related * events. */ FAR void *connection_private; void (*connection_event)(FAR struct tcp_conn_s *conn, uint16_t flags); }; /* 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 */ 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 # define EXTERN extern "C" extern "C" { #else # define EXTERN extern #endif /**************************************************************************** * Public Function Prototypes ****************************************************************************/ struct sockaddr; /* Forward reference */ struct socket; /* Forward reference */ struct pollfd; /* Forward reference */ /**************************************************************************** * Name: tcp_initialize * * Description: * Initialize the TCP/IP connection structures. Called only once and only * from the UIP layer at start-up in normal user mode. * ****************************************************************************/ 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 driver level 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_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. * * Return: * 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); /**************************************************************************** * Function: 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 /**************************************************************************** * Function: 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 * * Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP "connection" to poll for TX data * * Return: * 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 * * Parameters: * dev - The device driver structure to use in the send operation * conn - The TCP "connection" to poll for TX data * hsed - The polling interval in halves of a second * * Return: * 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); /**************************************************************************** * Function: 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); /**************************************************************************** * Function: 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); /**************************************************************************** * Function: 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); /**************************************************************************** * Function: 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 * ****************************************************************************/ bool tcp_islistener(uint16_t portno); /**************************************************************************** * Function: 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 * * 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 * * Return: * 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_reset * * Description: * Send a TCP reset (no-data) message * * Parameters: * dev - The device driver structure to use in the send operation * * Return: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_reset(FAR struct net_driver_s *dev); /**************************************************************************** * Name: tcp_ack * * Description: * Send the SYN or SYNACK response. * * 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 * * Return: * None * * Assumptions: * Called from network stack logic with the network stack locked * ****************************************************************************/ void tcp_ack(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. * * 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 * * Return: * 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 * * 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 * * Return: * 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_ipv4_input * * Description: * Handle incoming TCP input with IPv4 header * * Parameters: * dev - The device driver structure containing the received TCP packet. * * Return: * 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 * * Parameters: * dev - The device driver structure containing the received TCP packet. * * Return: * 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); #endif /**************************************************************************** * Function: 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); /**************************************************************************** * Function: 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 * ****************************************************************************/ #ifdef CONFIG_NET_TCP_READAHEAD uint16_t tcp_datahandler(FAR struct tcp_conn_s *conn, FAR uint8_t *buffer, uint16_t nbytes); #endif /**************************************************************************** * Function: tcp_backlogcreate * * Description: * Called from the listen() logic to setup the backlog as specified in the * the listen arguments. * * Assumptions: * Called from normal user code. Interrupts may be disabled. * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG int tcp_backlogcreate(FAR struct tcp_conn_s *conn, int nblg); #else # define tcp_backlogcreate(c,n) (-ENOSYS) #endif /**************************************************************************** * Function: 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 stack 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 /**************************************************************************** * Function: 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 /**************************************************************************** * Function: 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: * Called from normal user code, but with interrupts disabled, * ****************************************************************************/ #if defined(CONFIG_NET_TCPBACKLOG) && !defined(CONFIG_DISABLE_POLL) bool tcp_backlogavailable(FAR struct tcp_conn_s *conn); #else # define tcp_backlogavailable(c) (false); #endif /**************************************************************************** * Function: 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: * Called from normal user code, but with interrupts disabled, * ****************************************************************************/ #ifdef CONFIG_NET_TCPBACKLOG FAR struct tcp_conn_s *tcp_backlogremove(FAR struct tcp_conn_s *conn); #else # define tcp_backlogremove(c) (NULL) #endif /**************************************************************************** * Function: 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 /**************************************************************************** * Function: tcp_accept * * Description: * This function implements accept() for TCP/IP sockets. See the * description of accept() for further information. * * 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); /**************************************************************************** * Function: 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). * * Parameters: * psock An instance of the internal socket structure. * buf Data to send * len Length of data to send * * Returned Value: * On success, returns the number of characters sent. On error, * -1 is returned, and errno is set appropriately: * * EAGAIN or EWOULDBLOCK * The socket is marked non-blocking and the requested operation * would block. * EBADF * An invalid descriptor was specified. * ECONNRESET * Connection reset by peer. * EDESTADDRREQ * The socket is not connection-mode, and no peer address is set. * EFAULT * An invalid user space address was specified for a parameter. * EINTR * A signal occurred before any data was transmitted. * EINVAL * Invalid argument passed. * EISCONN * The connection-mode socket was connected already but a recipient * was specified. (Now either this error is returned, or the recipient * specification is ignored.) * EMSGSIZE * The socket type requires that message be sent atomically, and the * size of the message to be sent made this impossible. * ENOBUFS * The output queue for a network interface was full. This generally * indicates that the interface has stopped sending, but may be * caused by transient congestion. * ENOMEM * No memory available. * ENOTCONN * The socket is not connected, and no target has been given. * ENOTSOCK * The argument s is not a socket. * EPIPE * The local end has been shut down on a connection oriented socket. * In this case the process will also receive a SIGPIPE unless * MSG_NOSIGNAL is set. * * Assumptions: * ****************************************************************************/ struct socket; ssize_t psock_tcp_send(FAR struct socket *psock, FAR const void *buf, size_t len); /**************************************************************************** * Function: 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 */ /**************************************************************************** * Function: 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); #endif /* CONFIG_NET_TCP_WRITE_BUFFERS */ /**************************************************************************** * Function: 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 */ /**************************************************************************** * Function: tcp_wrbuffer_dump * * Description: * Dump the contents of a write buffer. * ****************************************************************************/ #ifdef CONFIG_NET_TCP_WRITE_BUFFERS #ifdef CONFIG_DEBUG 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 */ /**************************************************************************** * Function: 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 * ****************************************************************************/ #ifdef HAVE_TCP_POLL int tcp_pollsetup(FAR struct socket *psock, FAR struct pollfd *fds); #endif /**************************************************************************** * Function: 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 * ****************************************************************************/ #ifdef HAVE_TCP_POLL int tcp_pollteardown(FAR struct socket *psock, FAR struct pollfd *fds); #endif #undef EXTERN #ifdef __cplusplus } #endif #endif /* CONFIG_NET_TCP */ #endif /* _NET_TCP_TCP_H */