protocol1.h

本人本科的毕业设计。基于Serpent密码的回退N协议的数据传输。希望可供大家参考。谢谢诶！

typedef enum {data, ack, nak} frame_kind;	/* frame_kind definition */
typedef struct frame{	/* frames are transported in this layer */
// frame_kind kind;	/* what kind of a frame is it? */
 frame_kind frameType;
 unsigned int seq;   	/* sequence number */
// seq_nr ack;   	/* acknowledgement number */
 unsigned long info;  	/* the network layer packet */
} pFrame;
/* Wait for an event to happen; return its type in event. */
/*void wait_for_event(event_type *event);*/
struct param{
	CEdit* pEdit;
    DWORD dwIP;
};

/* Go get an inbound frame from the physical layer and copy it to r. */
void from_physical_layer(frame *r);

/* Pass the frame to the physical layer for transmission. */
void to_physical_layer(frame *s);

/* Start the clock running and enable the timeout event. */
//void start_timer(seq_nr k);

/* Stop the clock and disable the timeout event. */
//void stop_timer(seq_nr k);

/* Start an auxiliary timer and enable the ack_timeout event. */
//void start_ack_timer(void);

/* Stop the auxiliary timer and disable the ack_timeout event. */
//void stop_ack_timer(void);

/* Allow the network layer to cause a network_layer_ready event. */
void enable_network_layer(void);

/* Forbid the network layer from causing a network_layer_ready event. */
void disable_network_layer(void);

/* Macro inc is expanded in-line: Increment k circularly. */
#define inc(k) if (k < MAX_SEQ) k = k + 1; else k = 0