/****************************************************************************
* net/tcp/tcp.h
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef _NET_TCP_TCP_H
#define _NET_TCP_TCP_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <queue.h>
#include <nuttx/net/iob.h>
#include <nuttx/net/ip.h>
#ifdef CONFIG_NET_TCP
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Allocate a new TCP data callback */
#define tcp_callback_alloc(conn) devif_callback_alloc(&conn->list)
#define tcp_callback_free(conn,cb) devif_callback_free(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_conn_s
{
dq_entry_t node; /* Implements a doubly linked list */
net_ipaddr_t ripaddr; /* The IP address of the remote host */
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 */
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 */
uint16_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
****************************************************************************/
/* Defined in tcp_conn.c ****************************************************/
struct tcp_iphdr_s; /* 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 interrupt level when a TCP
* packet is received while "listening"
*
****************************************************************************/
FAR struct tcp_conn_s *tcp_alloc(void);
/****************************************************************************
* 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:
* This function is called from UIP logic at interrupt level
*
****************************************************************************/
FAR struct tcp_conn_s *tcp_active(struct tcp_iphdr_s *buf);
/****************************************************************************
* Name: tcp_nextconn()
*
* Description:
* Traverse the list of active TCP connections
*
* Assumptions:
* This function is called from UIP logic at interrupt level (or with
* interrupts disabled).
*
****************************************************************************/
FAR struct tcp_conn_s *tcp_nextconn(FAR struct tcp_conn_s *conn);
/****************************************************************************
* Name: tcp_listener()
*
* Description:
* Given a local port number (in network byte order), find the TCP
* connection that listens on this this port.
*
* Primary uses: (1) to determine if a port number is available, (2) to
* To identify the socket that will accept new connections on a local port.
*
****************************************************************************/
FAR struct tcp_conn_s *tcp_listener(uint16_t portno);
/****************************************************************************
* Name: tcp_alloc_accept()
*
* Description:
* Called when driver interrupt 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:
* This function is called from UIP logic at interrupt level
*
****************************************************************************/
FAR struct tcp_conn_s *tcp_alloc_accept(FAR struct tcp_iphdr_s *buf);
/****************************************************************************
* 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.
*
****************************************************************************/
#ifdef CONFIG_NET_IPv6
int tcp_bind(FAR struct tcp_conn_s *conn,
FAR const struct sockaddr_in6 *addr);
#else
int tcp_bind(FAR struct tcp_conn_s *conn,
FAR const struct sockaddr_in *addr);
#endif
/****************************************************************************
* 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.
*
****************************************************************************/
#ifdef CONFIG_NET_IPv6
int tcp_connect(FAR struct tcp_conn_s *conn,
FAR const struct sockaddr_in6 *addr);
#else
int tcp_connect(FAR struct tcp_conn_s *conn,
FAR const struct sockaddr_in *addr);
#endif
/* Defined in tcp_seqno.c ***************************************************/
/****************************************************************************
* Name: tcp_setsequence
*
* Description:
* Set the TCP/IP sequence number
*
* Assumptions:
* This function may called from the interrupt level
*
****************************************************************************/
void tcp_setsequence(FAR uint8_t *seqno, uint32_t value);
/****************************************************************************
* Name: tcp_getsequence
*
* Description:
* Get the TCP/IP sequence number
*
* Assumptions:
* This function may called from the interrupt level
*
****************************************************************************/
uint32_t tcp_getsequence(FAR uint8_t *seqno);
/****************************************************************************
* Name: tcp_addsequence
*
* Description:
* Add the length to get the next TCP sequence number.
*
* Assumptions:
* This function may called from the interrupt level
*
****************************************************************************/
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:
* This function may called from the interrupt level
*
****************************************************************************/
void tcp_initsequence(FAR uint8_t *seqno);
/****************************************************************************
* Name: tcp_nextsequence
*
* Description:
* Increment the TCP/IP sequence number
*
* Assumptions:
* This function is called from the interrupt level
*
****************************************************************************/
void tcp_nextsequence(void);
/* Defined in tcp_poll.c ****************************************************/
/****************************************************************************
* 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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
void tcp_poll(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn);
/* Defined in tcp_timer.c ***************************************************/
/****************************************************************************
* 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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
void tcp_timer(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
int hsec);
/* Defined in tcp_listen.c **************************************************/
/****************************************************************************
* 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 at interrupt level
*
****************************************************************************/
bool tcp_islistener(uint16_t portno);
/****************************************************************************
* Function: tcp_accept_connection
*
* Description:
* Accept the new connection for the specified listening port.
*
* Assumptions:
* Called at interrupt level
*
****************************************************************************/
int tcp_accept_connection(FAR struct net_driver_s *dev,
FAR struct tcp_conn_s *conn, uint16_t portno);
/* Defined in tcp_send.c ****************************************************/
/****************************************************************************
* 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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
void tcp_ack(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
uint8_t ack);
/* Defined in tcp_appsend.c *************************************************/
/****************************************************************************
* 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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
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 the interrupt level or with interrupts disabled.
*
****************************************************************************/
void tcp_rexmit(FAR struct net_driver_s *dev, FAR struct tcp_conn_s *conn,
uint16_t result);
/* Defined in tcp_input.c ***************************************************/
/****************************************************************************
* Name: tcp_input
*
* Description:
* Handle incoming TCP input
*
* Parameters:
* dev - The device driver structure containing the received TCP packet.
*
* Return:
* None
*
* Assumptions:
* Called from the interrupt level or with interrupts disabled.
*
****************************************************************************/
void tcp_input(FAR struct net_driver_s *dev);
/* Defined in tcp_callback.c ************************************************/
/****************************************************************************
* Function: tcp_callback
*
* Description:
* Inform the application holding the TCP socket of a change in state.
*
* Assumptions:
* This function is called at the interrupt level with interrupts disabled.
*
****************************************************************************/
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.
* - This function is called at the interrupt level with interrupts disabled.
*
****************************************************************************/
#ifdef CONFIG_NET_TCP_READAHEAD
uint16_t tcp_datahandler(FAR struct tcp_conn_s *conn, FAR uint8_t *buffer,
uint16_t nbytes);
#endif
/* Defined in tcp_backlog.c *************************************************/
/****************************************************************************
* 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:
* The caller has disabled interrupts so that there can be no conflict
* with ongoing, interrupt driven activity
*
****************************************************************************/
#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 the interrupt level with interrupts disabled
*
****************************************************************************/
#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 the interrupt level with interrupts disabled
*
****************************************************************************/
#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
/* Defined in tcp_send_buffered.c or tcp_send_unbuffered.c ******************/
/****************************************************************************
* 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);
/* Defined in tcp_wrbuffer.c ************************************************/
/****************************************************************************
* 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 interrupts enabled.
*
****************************************************************************/
#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 interrupt level with interrupts disabled.
*
****************************************************************************/
#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 */
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_NET_TCP */
#endif /* _NET_TCP_TCP_H */
