udp-socket.h File Reference

#include "net/ip/uip.h"

Data Structures
struct	udp_socket

Typedefs
typedef void(*	udp_socket_input_callback_t )(struct udp_socket *c, void *ptr, const uip_ipaddr_t *source_addr, uint16_t source_port, const uip_ipaddr_t *dest_addr, uint16_t dest_port, const uint8_t *data, uint16_t datalen)
	A UDP socket callback function. More...

Functions
int	udp_socket_bind (struct udp_socket *c, uint16_t local_port)
	Bind a UDP socket to a local port. More...
int	udp_socket_close (struct udp_socket *c)
	Close a UDP socket. More...
int	udp_socket_connect (struct udp_socket *c, uip_ipaddr_t *remote_addr, uint16_t remote_port)
	Bind a UDP socket to a remote address and port. More...
int	udp_socket_register (struct udp_socket *c, void *ptr, udp_socket_input_callback_t receive_callback)
	Register a UDP socket. More...
int	udp_socket_send (struct udp_socket *c, const void *data, uint16_t datalen)
	Send data on a UDP socket. More...
int	udp_socket_sendto (struct udp_socket *c, const void *data, uint16_t datalen, const uip_ipaddr_t *addr, uint16_t port)
	Send data on a UDP socket to a specific address and port. More...

typedef void(* udp_socket_input_callback_t)(struct udp_socket *c, void *ptr, const uip_ipaddr_t *source_addr, uint16_t source_port, const uip_ipaddr_t *dest_addr, uint16_t dest_port, const uint8_t *data, uint16_t datalen)

A UDP socket callback function.

Parameters

c	A pointer to the struct udp_socket that received the data
ptr	An opaque pointer that was specified when the UDP socket was registered with udp_socket_register()
source_addr	The IP address from which the datagram was sent
source_port	The UDP port number, in host byte order, from which the datagram was sent
dest_addr	The IP address that this datagram was sent to
dest_port	The UDP port number, in host byte order, that the datagram was sent to
data	A pointer to the data contents of the UDP datagram
datalen	The length of the data being pointed to by the data pointer Each UDP socket has a callback function that is registered as part of the call to udp_socket_register(). The callback function gets called every time a UDP packet is received.

int udp_socket_bind	(	struct udp_socket *	c,
		uint16_t	local_port
	)

Bind a UDP socket to a local port.

Parameters

c	A pointer to the struct udp_socket that should be bound to a local port
local_port	The UDP port number, in host byte order, to bind the UDP socket to

Return values

-1	Binding the UDP socket to the local port failed
1	Binding the UDP socket to the local port succeeded This function binds the UDP socket to a local port so that it will begin to receive data that arrives on the specified port. A UDP socket will receive data addressed to the specified port number on any IP address of the host. A UDP socket that is bound to a local port will use this port number as a source port in outgoing UDP messages.

References NULL, udp_bind, udp_socket::udp_conn, and UIP_HTONS.

Referenced by httpd_init().

int udp_socket_close

(

struct udp_socket *

c

)

Close a UDP socket.

Parameters

c	A pointer to the struct udp_socket to be closed

Return values

-1	If closing the UDP socket failed
1	If closing the UDP socket succeeded This function closes a UDP socket that has previously been registered with udp_socket_register(). All registered UDP sockets must be closed before exiting the process that registered them, or undefined behavior may occur.

References NULL, udp_socket::udp_conn, and uip_udp_remove.

int udp_socket_connect	(	struct udp_socket *	c,
		uip_ipaddr_t *	remote_addr,
		uint16_t	remote_port
	)

Bind a UDP socket to a remote address and port.

Parameters

c	A pointer to the struct udp_socket that should be connected
remote_addr	The IP address of the remote host, or NULL if the UDP socket should only be connected to a specific port
remote_port	The UDP port number, in host byte order, to which the UDP socket should be connected

Return values

-1

Connecting the UDP socket failed

1

Connecting the UDP socket succeeded This function connects the UDP socket to a specific remote port and optional remote IP address. When a UDP socket is connected to a remote port and address, it will only receive packets that are sent from the remote port and address. When sending data over a connected UDP socket, the data will be sent to the connected remote address. A UDP socket can be connected to a remote port, but not a remote IP address, by providing a NULL parameter as the remote_addr parameter. This lets the UDP socket receive data from any IP address on the specified port.

References NULL, uip_udp_conn::ripaddr, uip_udp_conn::rport, udp_socket::udp_conn, UIP_HTONS, and uip_ipaddr_copy.

int udp_socket_register	(	struct udp_socket *	c,
		void *	ptr,
		udp_socket_input_callback_t	receive_callback
	)

Register a UDP socket.

Parameters

c	A pointer to the struct udp_socket that should be registered
ptr	An opaque pointer that will be passed to callbacks
receive_callback	A function pointer to the callback function that will be called when data arrives

Return values

-1	The registration failed
1	The registration succeeded This function registers the UDP socket with the system. A UDP socket must be registered before any data can be sent or received over the socket. The caller must allocate memory for the struct udp_socket that is to be registered. A UDP socket can begin to receive data by calling udp_socket_bind().

References init, udp_socket::input_callback, input_callback, NULL, udp_socket::p, PROCESS_CONTEXT_BEGIN, PROCESS_CONTEXT_END, PROCESS_CURRENT, udp_socket::ptr, ptr, udp_socket::udp_conn, and udp_new().

Referenced by httpd_init().

int udp_socket_send	(	struct udp_socket *	c,
		const void *	data,
		uint16_t	datalen
	)

Send data on a UDP socket.

Parameters

c	A pointer to the struct udp_socket on which the data should be sent
data	A pointer to the data that should be sent
datalen	The length of the data to be sent

Returns

The number of bytes sent, or -1 if an error occurred

        This function sends data over a UDP socket. The UDP
        socket must have been connected to a remote address and
        port with udp_socket_connect().

References NULL, udp_socket::udp_conn, and uip_udp_packet_send().

int udp_socket_sendto	(	struct udp_socket *	c,
		const void *	data,
		uint16_t	datalen,
		const uip_ipaddr_t *	addr,
		uint16_t	port
	)

Send data on a UDP socket to a specific address and port.

Parameters

c	A pointer to the struct udp_socket on which the data should be sent
data	A pointer to the data that should be sent
datalen	The length of the data to be sent
addr	The IP address to which the data should be sent
port	The UDP port number, in host byte order, to which the data should be sent

Returns

The number of bytes sent, or -1 if an error occurred

        This function sends data over a UDP socket to a
        specific address and port.

        The UDP socket does not have to be connected to use
        this function.

References NULL, udp_socket::udp_conn, UIP_HTONS, and uip_udp_packet_sendto().