link.c

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#include "link.h"
#include <malloc.h>
#include <stdio.h>

/* 从链表头结点插入 */
void link_insert_front(struct  LINKLIST* THIS,void *data,int size)
{
	NODE *newNode=(NODE *)malloc(sizeof(NODE));
	//void* tdata =(void *)malloc(size);
	newNode->data=(void *)malloc(size);
	memset(newNode->data,0,size);
	//memset(tdata, 0 ,size);
	memcpy(newNode->data,data,size);
	//memcpy(tdata, data ,size);
//	newNode->data =tdata;

	newNode->prior=THIS->head;
	newNode->next=THIS->head->next;
	THIS->head->next->prior=newNode;
	THIS->head->next=newNode;
	THIS->count++;
}
/* 从链表尾结点插入*/
void link_insert_rear(struct  LINKLIST* THIS,void *data,int size)
{
	NODE *newNode=(NODE *)malloc(sizeof(NODE));
	newNode->data=(void *)malloc(size);
	memcpy(newNode->data,data,size); 
	newNode->next=THIS->rearptr;
	newNode->prior=THIS->rearptr->prior;
	THIS->rearptr->prior->next=newNode;
	THIS->rearptr->prior=newNode;
	THIS->count++;
}
/* 从链表某个结点插入*/
void link_insert_at(struct  LINKLIST* THIS,int index,void *data,int size)
{
/*	int i=0;
	NODE *temp=THIS->head->next;
	while(temp)
	{
		i++;
		if(i==index)
			break;
		temp=temp->next;
	}
	if(!temp)	return;
*/
	NODE *p=NULL;
	NODE *temp=THIS->get_node_by_index(THIS,index);
	if(!temp)	return;
	p=(NODE *)malloc(sizeof(NODE));
	if(!p)	return;
	p->data=malloc(size);
	if(!p->data)
	{
		free(p);
		return;
	}
	memcpy(p->data,data,size);
	p->prior=temp;
	p->next=temp->next;
	p->next->prior=p;
	temp->next=p;
	THIS->count++;
}

/*通过结点编号获得结点*/
static NODE* link_get_node_by_index(struct  LINKLIST* THIS,int index)
{
	int i=0;
	NODE *temp=THIS->rearptr;
	if (index<=0||index>THIS->count)
	{
		return NULL;
	} 
	else
	{
		for (i=0;i<index;i++)
		{
			temp=temp->prior;
		}
		return temp;
	}
}
/* 根据key值，并通过一定的比较算法cmp获取链表中的结点 */
NODE* link_get_node_by_key(struct  LINKLIST* THIS,char* key,int (*condition)(void *p1,void *p2))
{
	NODE *temp=THIS->rearptr->prior;
	if (THIS->count==0)
	{
		return NULL;
	} 
	else
	{
		while (temp->prior!=NULL)
		{
			if (condition(temp,key))
			{
				return temp;
			} 
			else
			{
				temp=temp->prior;
			}
		}
		return NULL;
	}
}
/* 获取结点在链表中的位置 */
int link_get_index_by_key(struct  LINKLIST* THIS,char* key,int (*condition)(void *p1,void *p2))
{
	NODE *temp=THIS->rearptr->prior;
	int i=1;
	if (THIS->count==0)
	{
		return 0;
	} 
	else
	{
		while (temp->prior!=NULL)
		{
			if (condition(temp,key))
			{
				return i;
			} 
			else
			{
				temp=temp->prior;
				i++;
			}
		}
		return 0;
	}
}

/*通过关键字删除结点*/
static int link_del_node_by_key(struct  LINKLIST* THIS,char* key,int (*condition)(void *p1,void *p2))
{
	NODE *p,*temp=THIS->head->next;
	while(temp)
	{
		if(condition(temp,key))
		{
			p=temp;
			temp->prior->next=temp->next;
			temp->next->prior=temp->prior;
			THIS->count--;
			free(p->data);
			free(p);
			return 1;
		}else
		{
			temp=temp->next;
		}
	}
	return 0;
}
/*删除第几个结点*/
int link_del_node_by_index(struct  LINKLIST* THIS,int index)
{
	NODE *temp=link_get_node_by_index(THIS,index);
	if (temp==NULL)
	{
		return 0;
	} 
	else
	{
		temp->next->prior=temp->prior;
		temp->prior->next=temp->next;
		THIS->count--;
		free(temp->data);
		free(temp);
		temp = NULL;
		return 1;
	}
}
/* 删除链表结点，但是不删除头尾结点 */
void link_del_all_data(struct  LINKLIST* THIS)
{
	NODE *temp=THIS->head->next;
	while (temp->next!=NULL)
	{
		THIS->head->next=temp->next;
		temp->next->prior=THIS->head;
		free(temp->data);
		free(temp);
		THIS->count--;
		temp=THIS->head->next;
	}
}
/* 删除链表,包括链表头表尾结点，本身结构体 */
void link_del_all(struct  LINKLIST** THIS)
{
	NODE *temp=(*THIS)->head->next;
	while (temp->next!=NULL)
	{
		(*THIS)->head->next=temp->next;
		temp->next->prior=(*THIS)->head;
		free(temp->data);
		free(temp);
		(*THIS)->count--;
		temp=(*THIS)->head->next;
	}
	free((*THIS));
}
int link_len(struct LINKLIST* THIS)
{
	NODE *temp=THIS->head->next;
	int count=0;
	while (temp->next!=NULL)
	{
		count++;
		temp=temp->next;
	}
	return count;
}
/*创建一个链表*/
LINK * new_link()

{
	
	LINK * link=NULL;
	NODE *node=NULL;
	NODE *node1=NULL;
	link=(LINK *)malloc(sizeof(LINK));
	if(link==NULL)	return link;
    
	node = (NODE*)malloc(sizeof(NODE));
	node1= (NODE*)malloc(sizeof(NODE));
	if(node==NULL)
	{
		if (node1==NULL)
		{
			free(link);
			return NULL;
		} 
		else
		{
			free(link);
			free(node1);
			return NULL;
		}
	}else
	{
		if (node1==NULL)
		{
			free(link);
			free(node);
			return NULL;
		} 
	}   
	link->head = node;   
	link->rearptr = node1;
	node->next=node1;
	node->prior=NULL;
	node1->next=NULL;
	node1->prior=node;
	
	link->count = 0;

	link->insert_front=link_insert_front;
	link->insert_rear=link_insert_rear;
	link->insert_at=link_insert_at;
	link->get_node_by_index=link_get_node_by_index;
	link->get_node_by_key=link_get_node_by_key;
	link->get_index_by_key=link_get_index_by_key;
	link->del_node_by_key=link_del_node_by_key;
	link->del_node_by_index=link_del_node_by_index;
	link->del_all_data=link_del_all_data;
	link->del_all=link_del_all;
	link->len=link_len;
	return link;

}