tcp.h File Reference

#include "lwip/opt.h"
#include "lwip/tcpbase.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include "lwip/ip.h"
#include "lwip/icmp.h"
#include "lwip/err.h"
#include "lwip/ip6.h"
#include "lwip/ip6_addr.h"

Data Structures
struct	tcp_ext_arg_callbacks
struct	tcp_pcb_listen
struct	tcp_pcb

Macros
#define	TCP_PCB_COMMON(type)
#define	tcp_mss(pcb)   ((pcb)->mss)
#define	tcp_sndbuf(pcb)   (TCPWND16((pcb)->snd_buf))
#define	tcp_sndqueuelen(pcb)   ((pcb)->snd_queuelen)
#define	tcp_nagle_disable(pcb)   tcp_set_flags(pcb, TF_NODELAY)
#define	tcp_nagle_enable(pcb)   tcp_clear_flags(pcb, TF_NODELAY)
#define	tcp_nagle_disabled(pcb)   tcp_is_flag_set(pcb, TF_NODELAY)
#define	tcp_listen(pcb)   tcp_listen_with_backlog(pcb, TCP_DEFAULT_LISTEN_BACKLOG)

Typedefs
typedef err_t(*	tcp_accept_fn) (void *arg, struct tcp_pcb *newpcb, err_t err)
typedef err_t(*	tcp_recv_fn) (void *arg, struct tcp_pcb *tpcb, struct pbuf *p, err_t err)
typedef err_t(*	tcp_sent_fn) (void *arg, struct tcp_pcb *tpcb, u16_t len)
typedef err_t(*	tcp_poll_fn) (void *arg, struct tcp_pcb *tpcb)
typedef void(*	tcp_err_fn) (void *arg, err_t err)
typedef err_t(*	tcp_connected_fn) (void *arg, struct tcp_pcb *tpcb, err_t err)
typedef void(*	tcp_extarg_callback_pcb_destroyed_fn) (u8_t id, void *data)
typedef err_t(*	tcp_extarg_callback_passive_open_fn) (u8_t id, struct tcp_pcb_listen *lpcb, struct tcp_pcb *cpcb)

Functions
struct tcp_pcb *	tcp_new (void)
struct tcp_pcb *	tcp_new_ip_type (u8_t type)
void	tcp_arg (struct tcp_pcb *pcb, void *arg)
void	tcp_recv (struct tcp_pcb *pcb, tcp_recv_fn recv)
void	tcp_sent (struct tcp_pcb *pcb, tcp_sent_fn sent)
void	tcp_err (struct tcp_pcb *pcb, tcp_err_fn err)
void	tcp_accept (struct tcp_pcb *pcb, tcp_accept_fn accept)
void	tcp_poll (struct tcp_pcb *pcb, tcp_poll_fn poll, u8_t interval)
void	tcp_backlog_delayed (struct tcp_pcb *pcb)
void	tcp_backlog_accepted (struct tcp_pcb *pcb)
void	tcp_recved (struct tcp_pcb *pcb, u16_t len)
err_t	tcp_bind (struct tcp_pcb *pcb, const ip_addr_t *ipaddr, u16_t port)
void	tcp_bind_netif (struct tcp_pcb *pcb, const struct netif *netif)
err_t	tcp_connect (struct tcp_pcb *pcb, const ip_addr_t *ipaddr, u16_t port, tcp_connected_fn connected)
struct tcp_pcb *	tcp_listen_with_backlog_and_err (struct tcp_pcb *pcb, u8_t backlog, err_t *err)
struct tcp_pcb *	tcp_listen_with_backlog (struct tcp_pcb *pcb, u8_t backlog)
void	tcp_abort (struct tcp_pcb *pcb)
err_t	tcp_close (struct tcp_pcb *pcb)
err_t	tcp_shutdown (struct tcp_pcb *pcb, int shut_rx, int shut_tx)
err_t	tcp_write (struct tcp_pcb *pcb, const void *dataptr, u16_t len, u8_t apiflags)
void	tcp_setprio (struct tcp_pcb *pcb, u8_t prio)
err_t	tcp_output (struct tcp_pcb *pcb)
u8_t	tcp_ext_arg_alloc_id (void)
void	tcp_ext_arg_set_callbacks (struct tcp_pcb *pcb, uint8_t id, const struct tcp_ext_arg_callbacks *const callbacks)
void	tcp_ext_arg_set (struct tcp_pcb *pcb, uint8_t id, void *arg)
void *	tcp_ext_arg_get (const struct tcp_pcb *pcb, uint8_t id)

Detailed Description

TCP API (to be used from TCPIP thread)
See also TCP

Macro Definition Documentation

TCP_PCB_COMMON

#define TCP_PCB_COMMON

(

type

)

Value:

type *next; /* for the linked list */ \
  void *callback_arg; \
  TCP_PCB_EXTARGS \
  enum tcp_state state; /* TCP state */ \
  u8_t prio; \
  /* ports are in host byte order */ \
  u16_t local_port

members common to struct tcp_pcb and struct tcp_listen_pcb

Typedef Documentation

tcp_accept_fn

typedef err_t(* tcp_accept_fn) (void *arg, struct tcp_pcb *newpcb, err_t err)

Function prototype for tcp accept callback functions. Called when a new connection can be accepted on a listening pcb.

Parameters

arg	Additional argument to pass to the callback function (

See also

tcp_arg())

Parameters

newpcb	The new connection pcb
err	An error code if there has been an error accepting. Only return ERR_ABRT if you have called tcp_abort from within the callback function!

tcp_connected_fn

typedef err_t(* tcp_connected_fn) (void *arg, struct tcp_pcb *tpcb, err_t err)

Function prototype for tcp connected callback functions. Called when a pcb is connected to the remote side after initiating a connection attempt by calling tcp_connect().

Parameters

arg	Additional argument to pass to the callback function (

See also

tcp_arg())

Parameters

tpcb	The connection pcb which is connected
err	An unused error code, always ERR_OK currently ;-)

Note

When a connection attempt fails, the error callback is currently called!

tcp_err_fn

typedef void(* tcp_err_fn) (void *arg, err_t err)

Function prototype for tcp error callback functions. Called when the pcb receives a RST or is unexpectedly closed for any other reason.

Note

The corresponding pcb is already freed when this callback is called!

Parameters

arg	Additional argument to pass to the callback function (

See also

tcp_arg())

Parameters

err	Error code to indicate why the pcb has been closed ERR_ABRT: aborted through tcp_abort or by a TCP timer ERR_RST: the connection was reset by the remote host

tcp_extarg_callback_passive_open_fn

typedef err_t(* tcp_extarg_callback_passive_open_fn) (u8_t id, struct tcp_pcb_listen *lpcb, struct tcp_pcb *cpcb)

Function prototype to transition arguments from a listening pcb to an accepted pcb

Parameters

id	ext arg id (allocated via tcp_ext_arg_alloc_id)
lpcb	the listening pcb accepting a connection
cpcb	the newly allocated connection pcb

Returns

ERR_OK if OK, any error if connection should be dropped

tcp_extarg_callback_pcb_destroyed_fn

typedef void(* tcp_extarg_callback_pcb_destroyed_fn) (u8_t id, void *data)

Function prototype for deallocation of arguments. Called just before the pcb is freed, so don't expect to be able to do anything with this pcb!

Parameters

id	ext arg id (allocated via tcp_ext_arg_alloc_id)
data	pointer to the data (set via tcp_ext_arg_set before)

tcp_poll_fn

typedef err_t(* tcp_poll_fn) (void *arg, struct tcp_pcb *tpcb)

Function prototype for tcp poll callback functions. Called periodically as specified by

See also

tcp_poll.

Parameters

arg	Additional argument to pass to the callback function (

See also

tcp_arg())

Parameters

tpcb

tcp pcb

Returns

ERR_OK: try to send some data by calling tcp_output Only return ERR_ABRT if you have called tcp_abort from within the callback function!

tcp_recv_fn

typedef err_t(* tcp_recv_fn) (void *arg, struct tcp_pcb *tpcb, struct pbuf *p, err_t err)

Function prototype for tcp receive callback functions. Called when data has been received.

Parameters

arg	Additional argument to pass to the callback function (

See also

tcp_arg())

Parameters

tpcb	The connection pcb which received data
p	The received data (or NULL when the connection has been closed!)
err	An error code if there has been an error receiving Only return ERR_ABRT if you have called tcp_abort from within the callback function!

tcp_sent_fn

typedef err_t(* tcp_sent_fn) (void *arg, struct tcp_pcb *tpcb, u16_t len)

Function prototype for tcp sent callback functions. Called when sent data has been acknowledged by the remote side. Use it to free corresponding resources. This also means that the pcb has now space available to send new data.

Parameters

arg	Additional argument to pass to the callback function (

See also

tcp_arg())

Parameters

tpcb	The connection pcb for which data has been acknowledged
len	The amount of bytes acknowledged

Returns

ERR_OK: try to send some data by calling tcp_output Only return ERR_ABRT if you have called tcp_abort from within the callback function!

Function Documentation

tcp_setprio()

void tcp_setprio	(	struct tcp_pcb *	pcb,
		u8_t	prio
	)

Sets the priority of a connection.

Parameters

pcb	the tcp_pcb to manipulate
prio	new priority