Nut/OS  4.10.3
API Reference
sock_var.h File Reference

UDP and TCP socket interface definitions. More...

#include <compiler.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/device.h>
#include <dev/netbuf.h>
#include <netinet/tcp_fsm.h>
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Data Structures

struct  udp_socket
 UDP socket information structure. More...
struct  tcp_socket
 TCP socket information structure. More...


#define SO_FIN   0x01
 Socket transmit flag. Send FIN after all data has been transmitted.
#define SO_SYN   0x02
 Socket transmit flag. Send SYN first.
#define SO_FORCE   0x08
 Socket transmit flag. Force sending ACK.
#define SO_ACK   0x10
 Socket transmit flag. Send ACK.


typedef struct udp_socket UDPSOCKET
 UDP socket type.
typedef struct tcp_socket TCPSOCKET
 TCP socket type.


int NutUdpInput (NUTDEVICE *dev, NETBUF *nb)
 Handle incoming UDP packets.
int NutUdpOutput (UDPSOCKET *sock, uint32_t dest, uint16_t port, NETBUF *nb)
 Send a UDP packet.
int NutTcpOutput (TCPSOCKET *sock, CONST uint8_t *data, uint16_t size)
 Initiate TCP segment transmission.
int NutTcpReject (NETBUF *nb)
 Reject an incoming segment.

Detailed Description

UDP and TCP socket interface definitions.

Definition in file sock_var.h.

Function Documentation

int NutTcpOutput ( TCPSOCKET sock,
CONST uint8_t data,
uint16_t  size 

Initiate TCP segment transmission.

Check the TCP socket status and send any segment waiting for transmission.

The function will not return until the data has been stored in the network device hardware for transmission. If the device is not ready for transmitting a new packet, the calling thread will be suspended until the device becomes ready again.

If the target host is connected through an Ethernet network and if the hardware address of that host is currently unknown, an ARP request is sent out and the function will block until a response is received or an ARP timeout occurs.

Segments containing data or SYN and FIN flags are added to a special queue for unacknowledged segments and will be retransmitted by the TCP timer thread, if not acknowledged by the remote within a specific time. The state machine will remove these segments from the queue as soon as they are acknowledged.

This function is mainly used by the TCP state machine. Applications typically do not call this function but use NutTcpSend(), which is part of the TCP socket interface.
sockSocket descriptor. This pointer must have been retrieved by calling NutTcpCreateSocket().
dataPointer to TCP segment contents.
sizeTCP segment length.
0 on success, -1 otherwise. Returning 0 does not imply that the data has been successfully delivered, because flow control and retransmission is still handled in the background.

Definition at line 209 of file tcpout.c.

References __tcp_trf, __tcp_trs, ENOBUFS, htonl, htons, IPPROTO_TCP, memcpy(), _NETBUF::nb_ap, _NETBUF::nb_next, _NETBUF::nb_tp, NBAF_APPLICATION, NBAF_TRANSPORT, ntohl, NutDumpTcpHeader(), NutGetMillis(), NutIpChkSum(), NutIpChkSumPartial(), NutIpOutput(), NutIpPseudoChkSumPartial(), NutNetBufAlloc(), NutNetBufClonePart(), NutNetBufFree(), SO_ACK, SO_FIN, SO_FORCE, tcp_socket::so_last_error, tcp_socket::so_local_addr, tcp_socket::so_local_port, tcp_socket::so_mss, tcp_socket::so_remote_addr, tcp_socket::so_remote_port, tcp_socket::so_retran_time, tcp_socket::so_rtt_seq, tcp_socket::so_rx_nxt, tcp_socket::so_rx_win, SO_SYN, tcp_socket::so_tx_flags, tcp_socket::so_tx_nbq, tcp_socket::so_tx_nxt, _NBDATA::sz, TCPOLEN_MAXSEG, TCPOPT_MAXSEG, TH_ACK, tcphdr::th_ack, tcphdr::th_dport, TH_FIN, tcphdr::th_flags, tcphdr::th_off, TH_PUSH, tcphdr::th_seq, tcphdr::th_sport, tcphdr::th_sum, TH_SYN, tcphdr::th_urp, tcphdr::th_win, tcphdr::th_x2, and _NBDATA::vp.

Referenced by NutTcpSend(), NutTcpSm(), and NutTcpStateWindowEvent().

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int NutTcpReject ( NETBUF nb)

Reject an incoming segment.

Send RST in response to an incoming segment, which should be rejected.

The function avoids to send out a RST segment in response to an incoming RST segment.

This function is mainly used by the TCP state machine. Applications typically do not call this function.
nbNetwork buffer structure of the incoming segment. Will be released within this function.
0 on success, -1 otherwise.

Definition at line 395 of file tcpout.c.

References __tcp_trf, __tcp_trs, htonl, htons, ip::ip_dst, ip::ip_src, IPPROTO_TCP, _NETBUF::nb_ap, _NETBUF::nb_nw, _NETBUF::nb_tp, ntohl, NutDumpTcpHeader(), NutIpChkSum(), NutIpOutput(), NutIpPseudoChkSumPartial(), NutNetBufFree(), _NBDATA::sz, TH_ACK, TH_RST, TH_SYN, and _NBDATA::vp.

Referenced by NutTcpSm(), and NutTcpStateMachine().

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