#ifndef _ZTCP_H#define _ZTCP_H#include "zarch.h"#include "zdef.h"#include "zbuffer.h"#include "znetif.h"#include "zipv4.h"#include "zsocket.h"#define TCP_ACCEPT_NUMBER	5#define TCP_SEGMENT_NUMBER	32STRUCT_BEGINtypedef struct _tcp_header{	u16_t src;	u16_t dest;	u32_t seqno;	u32_t ackno;	u16_t _offset_flags;	u16_t wnd;	u16_t chksum;	u16_t urgp;}tcp_header_t;STRUCT_ENDtypedef enum _tcp_state {	CLOSED	    = 0,	LISTEN	    = 1,	SYN_SENT    = 2,	SYN_RCVD    = 3,	ESTABLISHED = 4,	FIN_WAIT_1  = 5,	FIN_WAIT_2  = 6,	CLOSE_WAIT  = 7,	CLOSING	    = 8,	LAST_ACK    = 9,	TIME_WAIT   = 10}tcp_state;/* This structure is used to repressent TCP segments. * Our segment include TCP + ETH + IP + DATA because simple*/typedef struct _tcp_seg{		struct _tcp_seg *next;		/*segment chain*/		u16_t len;					/* the TCP length of this segment */		tcp_header_t *ptcpheader; 	/* the TCP's header information*/		zbuffer_t	*pbuffer;			/* pointer to real data's zbuffer*/		void 		*pdata;			/* pointer to real data's position*/				u8_t	_id;				/*used for segment alloc and free*/		zbuffer_t *_ori_pbuffer;	/* data + TCP header + IP + eth */}tcp_seg_t;typedef struct _tcp_pcb{	struct _tcp_pcb *next;	zsocket_t	*_psocket;		/*identify of TCP socket*/	u8_t		user_state;	/*used for API function, such as poll or block*/	sys_sem_t	user_sem;	/*used for API function wait a EVENT*/		s8_t		accept;		/*if this is a SERVER tcp socket*/	struct	_tcp_pcb	*server;	/*if this pcb is accepted from a server*/			tcp_state	state;			/*the state of TCP */	/* receiver varables */	u32_t rcv_nxt;	 /* next seqno expected */	u16_t rcv_wnd;	 /* receiver window */	/* Timers */	u32_t tmr;	/* Retransmission timer. */	u8_t rtime;	u16_t mss;   /* maximum segment size */	u8_t flags;#define TF_ACK_DELAY 0x01   /* Delayed ACK. */#define TF_ACK_NOW   0x02   /* Immediate ACK. */#define TF_INFR	     0x04   /* In fast recovery. */#define TF_RESET     0x08   /* Connection was reset. */#define TF_CLOSED    0x10   /* Connection was sucessfully closed. */#define TF_GOT_FIN   0x20   /* Connection was closed by the remote end. */	/* RTT estimation variables. */	u16_t rttest; /* RTT estimate in 500ms ticks */	u32_t rtseq;  /* sequence number being timed */	s32_t sa, sv;	u16_t rto;    /* retransmission time-out */	u8_t nrtx;    /* number of retransmissions */	/* fast retransmit/recovery */	u32_t lastack; /* Highest acknowledged seqno. */	u8_t dupacks;	u16_t	acked;	/* congestion avoidance/control variables */	u16_t cwnd;	u16_t ssthresh;	/* sender variables */	u32_t snd_nxt,	     /* next seqno to be sent */	snd_max,       /* Highest seqno sent. */	snd_wnd,       /* sender window */	snd_wl1, snd_wl2,	snd_lbb;	u16_t snd_buf;	 /* Avaliable buffer space for sending. */	u8_t snd_queuelen;	u8_t polltmr, pollinterval;	tcp_seg_t *unsent;	tcp_seg_t *unacked;	zbuffer_t	*recv_pbuf;		/*read data buffer*/}tcp_pcb_t;#define TCP_SEQ_LT(a,b)	    ((s32_t)((a)-(b)) < 0)#define TCP_SEQ_LEQ(a,b)    ((s32_t)((a)-(b)) <= 0)#define TCP_SEQ_GT(a,b)	    ((s32_t)((a)-(b)) > 0)#define TCP_SEQ_GEQ(a,b)    ((s32_t)((a)-(b)) >= 0)#define TCP_FIN 0x01#define TCP_SYN 0x02#define TCP_RST 0x04#define TCP_PSH 0x08#define TCP_ACK 0x10#define TCP_URG 0x20/* Length of the TCP header, excluding options. */#define TCP_HEAD_LEN 20/* ---------- TCP options ---------- */#define TCP_TTL			255/* Controls if TCP should queue segments that arrive out of   order. Define to 0 if your device is low on memory. */#define TCP_QUEUE_OOSEQ		1/* TCP Maximum segment size. */#define TCP_MSS			1024/* TCP sender buffer space (bytes). */#define TCP_SND_BUF		4096/* TCP sender buffer space (segment). This must be at least = 2 *   TCP_SND_BUF/TCP_MSS for things to work. */#define TCP_SND_QUEUELEN	TCP_SND_BUF/TCP_MSS/* TCP receive window. */#define TCP_WND			1024*4/* Maximum number of retransmissions of data segments. */#define TCP_MAXRTX		7	/*We have reduce to 7 from 12 --zhouchang*//* Maximum number of retransmissions of SYN segments. */#define TCP_SYNMAXRTX		4/*time const for TCP*/#define TCP_TMR_INTERVAL       100  /*The TCP timer interval in milliseconds. */#define TCP_FAST_INTERVAL      200  /* the fine grained timeout in												  milliseconds */#define TCP_SLOW_INTERVAL      500  /* the coarse grained timeout in												  milliseconds */#define TCP_FIN_WAIT_TIMEOUT 20000 /* milliseconds */#define TCP_SYN_RCVD_TIMEOUT 20000 /* milliseconds */#define TCP_LASK_ACK_TIMEOUT 20000 /* milliseconds */#define TCP_OOSEQ_TIMEOUT	 6 /* x RTO */#define TCP_MSL 60000  /* The maximum segment lifetime in microseconds *//*------------------------------------------------------*/#define TCPH_OFFSET(hdr) (NTOHS((hdr)->_offset_flags) >> 8)#define TCPH_FLAGS(hdr) (NTOHS((hdr)->_offset_flags) & 0xff)#define TCPH_OFFSET_SET(hdr, offset) (hdr)->_offset_flags = HTONS(((offset) << 8) | TCPH_FLAGS(hdr))#define TCPH_FLAGS_SET(hdr, flags) (hdr)->_offset_flags = HTONS((TCPH_OFFSET(hdr) << 8) | (flags))#define TCP_TCPLEN(seg) ((seg)->len + ((TCPH_FLAGS((seg)->ptcpheader) & TCP_FIN || TCPH_FLAGS((seg)->ptcpheader) & TCP_SYN)? 1: 0))#define TCP_REG(pcbs, npcb) do { \			    (npcb)->next = *(pcbs);\			    *(pcbs) = (npcb);\			    } while(0)#define TCP_RMV(pcbs, npcb) do { \			    if(*(pcbs) == (npcb)) { \			       *(pcbs) = (*(pcbs))->next; \			    } else for(tcp_tmp_pcb = *(pcbs); tcp_tmp_pcb != NULL; tcp_tmp_pcb = tcp_tmp_pcb->next) { \			       if(tcp_tmp_pcb->next != NULL && tcp_tmp_pcb->next == (npcb)) { \				  tcp_tmp_pcb->next = (npcb)->next; \				  break; \			       } \			    } \			    (npcb)->next = NULL; \			    } while(0)/*tcp_ack just ack seqno and don't send data if ACK_DELAY have beed set*/#define tcp_ack(pcb)	 if((pcb)->flags & TF_ACK_DELAY) { \			    (pcb)->flags |= TF_ACK_NOW; \			    tcp_output(pcb); \			 } else { \			    (pcb)->flags |= TF_ACK_DELAY; \			 }#define tcp_ack_now(pcb) (pcb)->flags |= TF_ACK_NOW; \                         tcp_output(pcb)#define MIN(x,y) (x) < (y)? (x): (y)#define UMAX(a, b)      ((a) > (b) ? (a) : (b))/* Definitions for error constants. */#define ERR_OK    0      /* No error, everything OK. */#define ERR_MEM  -1      /* Out of memory error.     */#define ERR_BUF  -2      /* Buffer error.            */#define ERR_ABRT -3      /* Connection aborted.      */#define ERR_RST  -4      /* Connection reset.        */#define ERR_CLSD -5      /* Connection closed.       */#define ERR_CONN -6      /* Not connected.           */#define ERR_VAL  -7      /* Illegal value.           */#define ERR_ARG  -8      /* Illegal argument.        */#define ERR_RTE  -9      /* Routing problem.         */#define ERR_USE  -10     /* Address in use.          */		extern u32_t	tcp_ticks;extern tcp_pcb_t	*ptcp_active_chain;extern tcp_pcb_t	*ptcp_listen_chain;extern tcp_pcb_t	*ptcp_tw_chain;	extern void tcp_init(void);extern void tcp_input(znetif_t *pnetif, zbuffer_t *pbuffer);extern u8_t	tcp_open(zsocket_t *psocket);extern u8_t	tcp_listen(zsocket_t *psocket);extern s8_t	tcp_accept(zsocket_t *psocket);extern u8_t tcp_recv(zsocket_t *psocket, zbuffer_t **ppbuffer, u8_t flags);extern u8_t	tcp_send(zsocket_t *psocket, u8_t *pdata, u16_t *len, u8_t flags);extern u8_t tcp_close(zsocket_t *psocket);extern void tcp_debug(s8_t id, u8_t cmd);extern void tcp_tmr(void *pdata);extern tcp_pcb_t *tcp_pcb_new(zsocket_t *psocket);extern void tcp_pcb_delete(tcp_pcb_t *ptcp);extern tcp_pcb_t *tcp_pcb_query(s8_t id);extern void tcp_pcb_dump(tcp_pcb_t *ptcp);extern void tcp_pcb_remove(tcp_pcb_t **pplist, tcp_pcb_t *ptcp);extern void tcp_pcb_clean(tcp_pcb_t *ptcp);extern void tcp_abort(tcp_pcb_t *ptcp, zbuffer_t *pbuffer);extern s8_t tcp_pcb_close(tcp_pcb_t *ptcp);s8_t tcp_insert_queue( tcp_pcb_t *ptcp, void *pdata, u16_t data_len, u8_t flags,u8_t *optdata, u8_t opt_len);extern tcp_seg_t *tcp_seg_new(void);void tcp_rexmit_seg(tcp_pcb_t *ptcp, tcp_seg_t *seg);extern void tcp_seg_dump(tcp_seg_t *pseg);extern void tcp_seg_delete(tcp_seg_t *pseg);extern u8_t tcp_reset(znetif_t *pnetif, ip_header_t *pipheader, tcp_header_t *ptcpheader);extern u8_t tcp_ip_out(znetif_t *pnetif, ipaddr_t *pdest_ip, ipaddr_t *psrc_ip,zbuffer_t * pbuffer);extern s8_t tcp_output(tcp_pcb_t *ptcp);#endif