linktab.c

linux平台下的网络通讯程序

#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <string.h>
#include <netinet/in.h>
#include <sys/socket.h>
#define MAX_BUF_SIZE 1024
#define MIN_BUF_SIZE 256

void exit();
void *malloc(unsigned size);
void free(void *ptr);
typedef struct
{
	struct sockaddr_in addr;
	socklen_t addrlen;
}IPINFO;
typedef struct
{
	char uid[MIN_BUF_SIZE];
	IPINFO from;
}UINFO;
//结点
typedef struct node
{
	UINFO info;
	struct node *next;
	struct node *pre;
}NODE;
//头结点
typedef struct
{
	UINFO top;
	NODE *head;
	NODE *tail;
	int len;
}HEADNODE;
//创建头结点
void showUid(HEADNODE *head)
{
	NODE *p;
	p=head->head;
	int i=0;
	while(p!=NULL)
	{
		printf("[%d]uid = %s ",i++,p->info.uid);
		p=p->next;
	}
}
HEADNODE *createHead()
{
	HEADNODE *p;
	if((p=(HEADNODE *)malloc(sizeof(HEADNODE)))==NULL)
	{
		fprintf(stderr,"Out of memony!%s\n",strerror(errno));
		exit(1);
	}
	p->len=0;
	//空表头指针和尾指针都为空
	p->head=NULL;
	p->tail=NULL;
	return p;
}
//添加结点
NODE *addNode(HEADNODE *head,UINFO *sp)
{	
	NODE *newNode=NULL;
	if((newNode=(NODE *)malloc(sizeof(NODE)))==NULL)
	{
		fprintf(stderr,"Out of memony!%s\n",strerror(errno));
		return NULL;
	}
	strcpy(newNode->info.uid,sp->uid);
	newNode->info.from = sp->from;
	printf("newNode uid = %s \n",newNode->info.uid);
	if(NULL==head->head)
	{
		//表为空表的情况
		newNode->pre=NULL;
		newNode->next=NULL;
		head->head=newNode;
		head->tail=newNode;
	}
	else
	{
		//表不为空
		head->tail->next=newNode;
		newNode->pre=head->tail;
		newNode->next=NULL;
		head->tail=newNode;
	}
	(head->len)++;
	//showUid(head);
	return newNode;	
}
int delNode(HEADNODE *head,UINFO *sp)
{
	int n;
	if(head->head==NULL)
	{
		return 0;
	}
	NODE *curNode=head->head;
	while(curNode!=NULL)
	{
		//printf("tab uid = %s temp uid = %s ",curNode->info.uid,sp->uid);
		if((n=strcmp(curNode->info.uid,sp->uid))==0)
		{
			if(curNode->pre==NULL)
			{
				head->head=NULL;
				head->tail=NULL;
			}
			else if(curNode->next==head->tail)
			{
				head->tail=curNode->pre;
				curNode->pre->next=NULL;
			}
			else
			{
				curNode->pre->next=curNode->next;
				curNode->next->pre=curNode->pre;
			}
			(head->len)--;
			//printf("del node %s",curNode->info.uid);
			free(curNode);
			return 1;
		}
		curNode=curNode->next;
	}
	return 0;
}
void dropTab(HEADNODE *head)
{
	NODE *p1,*p2;
	p1=head->head;
	int i=0;
	while(p1!=NULL)
	{
		p2=p1->next;
		free(p1);
		p1=p2;
		printf("[%d]deleted\n ",++i);
	}
}
NODE *searchNode(const HEADNODE *head,UINFO *sp)
{
	if(head->head==NULL)
	{
		return NULL;
	}
	NODE *curNode=head->head;
	while(curNode!=NULL)
	{
		if(strcmp(curNode->info.uid,sp->uid)==0)
		{
			return curNode;
		}
		curNode=curNode->next;
	}
	return NULL;
}
void listUid(HEADNODE *head,char *s)
{
	NODE *p=head->head;
	int i=0;
	s[0]=0;
	while(p!=NULL)
	{
		printf("u%i = %s\n",i,p->info.uid);
		strcat(s,p->info.uid);
		strcat(s,"\n");
		p=p->next;
		i++;
	}
	//printf("[uidlist][%d] = %s end\n",i,s);
}
/*
int main(void)
{
	HEADNODE *head = createHead();
	NODE *p;
	UINFO temp1;
	char tempstr[256];
	int i;
	for(i=0;i<3;i++)
	{
		printf("get uid :");
		fgets(temp1.uid,256,stdin);
		addNode(head,&temp1);
		bzero(&temp1,sizeof(UINFO));
	}
	p=head->head;
	i=0;
	while(p!=NULL)
	{
		printf("[%d]uid = %s ",i++,p->info.uid);
		p=p->next;
	}

	printf("search uid:");
	fgets(temp1.uid,256,stdin);
	p=searchNode(head,&temp1);
	printf("p uid = %s",p->info.uid);
	dropTab(head);
	return 0;
}
*/