Bidirectional linked list (we only need to pay attention to insert and delete functions)

Dlink_list.h

#ifndef _DLINKLIST_H_
#define _DLINKLIST_H_


#include "stdio.h"
#include "stdlib.h"



typedef struct _tag_Dlink_list_node Dlink_list_node;
struct _tag_Dlink_list_node
{
    
	Dlink_list_node *next;
	Dlink_list_node *pre;
};

typedef struct _tag_Dlink_list TDlink_list;
struct _tag_Dlink_list
{
    
    Dlink_list_node header;
    int length;
};

typedef struct _tag_Dlink_list_value Dlink_list_value;
struct _tag_Dlink_list_value
{
    
    Dlink_list_node node;
    int value;// It can replace complex structures 
};


TDlink_list* DLinkList_Create(void);
int DLinkList_Insert(TDlink_list* list, Dlink_list_node* node, int pos);
Dlink_list_node* DLinkList_Get(TDlink_list* list, int pos);
Dlink_list_node* DLinkList_Delete(TDlink_list* list, int pos);

// Additional extended functions 
Dlink_list_node* DLinkList_DeleteNode(TDlink_list* list, Dlink_list_node* node);

void DLinkList_printf(TDlink_list* list);




#endif

Dlink_list.c

#include "Dlink_list.h"

TDlink_list* DLinkList_Create(void)
{
    
    TDlink_list* ret = (TDlink_list*)malloc(sizeof(TDlink_list));
    
    if( ret != NULL )
    {
    
        ret->length = 0;
        ret->header.next = NULL;
        ret->header.pre = NULL;
    }
    
    return ret;
}

int DLinkList_Insert(TDlink_list* list, Dlink_list_node* node, int pos)
{
    

	int i;
	Dlink_list_node* next = NULL;
	Dlink_list_node* current = &(list->header);
	
	if (current==NULL && list->length==0)
	{
    
		list->header.next = node;
		list->header.pre = NULL;
		node->next = NULL;
		node->pre = NULL;
	}else
	{
    
		for (i=0; i<pos&&(current->next!=NULL); i++)
		{
    
			current = current->next;
		}
		next = current->next;
		
		// Draw your own picture 
		current->next = node;
		node->next = next;
		if (next!=NULL)
		{
    
			next->pre = node;
		}
		node->pre = current;	
	}
	list->length++;
	
	return 0;

	

}


Dlink_list_node* DLinkList_Get(TDlink_list* list, int pos)
{
    
    int i = 0;
	Dlink_list_node *ret = NULL;
	
	if (list->length>pos)
	{
    
		ret = list->header.next;
		for (i=0; i<pos; i++)
		{
    
			ret = ret->next;
		}
	}
	return ret;
}

Dlink_list_node* DLinkList_Delete(TDlink_list* list, int pos)
{
    
    int i = 0;
	Dlink_list_node *current = NULL;
	Dlink_list_node *ret = NULL;
	Dlink_list_node *next = NULL;
	
	
	if (list->length && list->length>pos)
	{
    
		current = &(list->header);
		for (i=0; i<pos; i++)
		{
    
			current = current->next;
		}
		
		ret = current->next;
		next = ret->next;
		
		current->next = next;
		if (next!=NULL)
		{
    
			if (current == &(list->header) )
			{
    
				next->pre = NULL;
			}else
			{
    
				next->pre = current;
			}
		}
		list->length--;
	}else
	{
    
		printf("DLinkList_Delete error %d-%d\n",list->length,pos);
	}
	return ret;
	
}

Dlink_list_node* DLinkList_DeleteNode(TDlink_list* list, Dlink_list_node* node)
{
    
	int i;
	Dlink_list_node *ret = NULL;
	Dlink_list_node *current = &(list->header);
	
	for (i=0; i<list->length; i++)
	{
    
		if (current->next == node)
		{
    
			ret = current->next;
			break;
		}
		current = current->next;
	}
	
	if (ret != NULL)
	{
    
		DLinkList_Delete(list,i);
	}
	return ret;
}

void DLinkList_printf(TDlink_list* list)
{
    
	int i;
	Dlink_list_node *current = list->header.next;
	Dlink_list_value *tmp;
	
	printf("len:%d-",list->length);
	if (current != NULL)
	{
    
		for (i=0; i<list->length; i++)
		{
    
			tmp = (Dlink_list_value*)current;
			printf("[i:%d-v:%d]-",i,tmp->value);
			current = current->next;
		}
		printf("\n");
	}
}

Test code

#include "stdio.h"
#include "stdint.h"
#include "Dlink_list.h"



int main(void)
{
    
	#define BUF_SIZE 10
	int i;
	TDlink_list *head;
	Dlink_list_value buf[BUF_SIZE];
	
	printf("hello \r\n");
	
	for (i=0; i<BUF_SIZE; i++)
	{
    
		buf[i].value = i+1;
	}
	head = DLinkList_Create();
	
	for (i=0; i<BUF_SIZE; i++)
	{
    
		DLinkList_Insert(head,(Dlink_list_node*)&buf[i],0);
	}
	DLinkList_printf(head);
	
// for (i=0; i<BUF_SIZE; i++)
// {
    
// DLinkList_Delete(head,0);
// DLinkList_printf(head); 
// }
	
	for (i=BUF_SIZE-1; i>=0; i--)
	{
    
		DLinkList_Delete(head,i);
		DLinkList_printf(head);	
	}	
	
	while(1)
	{
    
	
	}
}