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TCP
[Protocols]

RFC 793 Transmission Control Protocol. More...

Functions
void	NutTcpInput (NETBUF *nb)
	Process incoming TCP segments from IP layer.
int	NutTcpStatePassiveOpenEvent (TCPSOCKET *sock)
	Initiated by the application.
int	NutTcpStateActiveOpenEvent (TCPSOCKET *sock)
	Initiated by the application.
int	NutTcpStateCloseEvent (TCPSOCKET *sock)
	Socket close by application.
int	NutTcpStateWindowEvent (TCPSOCKET *sock)
	Initiated by the application.
void	NutTcpStateRetranTimeout (TCPSOCKET *sock)
	Retransmit a segment after ACK timeout.
	NutTcpSm (void *arg)
	TCP state machine thread.
void	NutTcpStateMachine (NETBUF *nb)
	Process incoming TCP segments.
int	NutTcpInitStateMachine (void)
	Start TCP state machine.
int	IsInLimits (u_long x, u_long low, u_long high)
	Sequence number comparisons.

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Detailed Description

RFC 793 Transmission Control Protocol.

TCP provides reliable, in-sequence delivery of a full-duplex stream of octets. It is used by applications which need a reliable, connection-oriented data transport.

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Function Documentation

int IsInLimits (  u_long    x, u_long    low, u_long    high )

Sequence number comparisons. Return true if x is between low and high inclusive, false otherwise

int NutTcpInitStateMachine (  void    )

Start TCP state machine. The socket interface will automatically call this routine as soon as the first socket is created. Returns: 0 on success, -1 otherwise.

void NutTcpInput (  NETBUF *    nb )

Process incoming TCP segments from IP layer. Warning: The caller must take care not to pass broadcast or multicast segments. Note: This routine is called by the IP layer on incoming TCP segments. Applications typically do not call this function.

NutTcpSm (  void *    arg )

TCP state machine thread. The TCP state machine serves two purposes: It processes incoming TCP segments and handles TCP timers.

int NutTcpStateActiveOpenEvent (  TCPSOCKET *    sock )

Initiated by the application. The caller must make sure, that the socket is in closed state. Parameters: sock  Socket descriptor. This pointer must have been retrieved by calling NutTcpCreateSocket(). Returns: 0 if granted, -1 otherwise.

int NutTcpStateCloseEvent (  TCPSOCKET *    sock )

Socket close by application. If socket is in state SYN_RECEIVED or ESTABLISHED, it is changed to FINWAIT1. No further data sending is accepted. Receiving is still allowed. Parameters: sock  Socket descriptor. This pointer must have been retrieved by calling NutTcpCreateSocket().

void NutTcpStateMachine (  NETBUF *    nb )

Process incoming TCP segments. All incoming TCP packets are passed to this routine. They will be added to a global queue and processed by the TCP state machine, which is running on a separate thread. Note: This routine is called by the IP layer on incoming TCP segments. Applications typically do not call this function.

int NutTcpStatePassiveOpenEvent (  TCPSOCKET *    sock )

Initiated by the application. Parameters: sock  Socket descriptor. This pointer must have been retrieved by calling NutTcpCreateSocket(). Returns: 0 if granted, error code otherwise.

void NutTcpStateRetranTimeout (  TCPSOCKET *    sock )

Retransmit a segment after ACK timeout. This function is called by the TCP timer. Parameters: sock  Socket descriptor. This pointer must have been retrieved by calling NutTcpCreateSocket().

int NutTcpStateWindowEvent (  TCPSOCKET *    sock )

Initiated by the application. Parameters: sock  Socket descriptor. This pointer must have been retrieved by calling NutTcpCreateSocket().

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