head File:
LinkedList.h
/************************************
* *
* Author: Chen Jiezhu *
*November 2017*
* *
* *
*************************************/
/**Prevent duplicate references**/
#ifndef _LINKEDLIST_H
#define _LINKEDLIST_H
#endif
#define new(Class) (Class*)malloc(sizeof(Class))
#define findMethodByObject(Object, Method, ...) Object->Method(Object, __VA_ARGS__)
#ifdef __cplusplus
extern "C" {
#endif
typedef struct LinkedListItem ListItem;
typedef struct LinkedListHead ListHead;
struct LinkedListItem{
void* content;
ListItem *prev,
*next;
};
struct LinkedListHead{
ListItem *headItem;
ListItem * lastItem;
int length;
void (*removeItem)(ListHead* head, ListItem* item);
void (*removeItemByPosition)(ListHead* head, int pos);
void (*add)(ListHead* head, void* content);
void* (*get)(ListHead* head, int pos);
void (*insert)(ListHead* head, void* content, int pos);
};
void removeItem(ListHead* head, ListItem* item);
void removeItemByPosition(ListHead* head, int pos);
void add(ListHead* head, void* content);
void* get(ListHead* head, int pos);
void insert(ListHead* head, void* content, int pos);
#ifdef __cplusplus
}
#endif
#include "LinkedList.c"
Implementation file:
LinkedList.c
/************************************
* *
* Author: Chen Jiezhu *
*November 2017*
* *
* *
*************************************/
void removeItem(ListHead* head, ListItem* item){
ListItem *cursor = head->headItem;
if(item == NULL) return;
/**If you want to delete the head node**/
if(head->headItem == item){
head->headItem = head->headItem->next;
head->headItem->prev = NULL;
if(cursor->content != NULL)
free(cursor->content);
free(cursor);
head->length --;
return;
}
/**If you want to delete the trailing node**/
if(head->lastItem == item){
head->lastItem = head->lastItem->prev;
head->lastItem->next = NULL;
if(item->content != NULL)
free(item->content);
free(item);
head->length --;
return;
}
/**Other nodes**/
while(cursor != NULL){
if(cursor == item){
cursor->next->prev = cursor->prev;
cursor->prev->next = cursor->next;
if(item->content != NULL)
free(item->content);
free(item);
head->length --;
return;
}
cursor = cursor->next;
}
}
void removeItemByPosition(ListHead* head, int pos){
ListItem *cursor = head->headItem;
/**If you want to delete the head node**/
if(pos == 0){
head->headItem = head->headItem->next;
head->headItem->prev = NULL;
if(cursor->content != NULL)
free(cursor->content);
free(cursor);
head->length --;
return;
}
/**If you want to delete the trailing node**/
if(pos == head->length - 1){
head->lastItem = head->lastItem->prev;
head->lastItem->next = NULL;
if(cursor->content != NULL)
free(cursor->content);
free(cursor);
head->length --;
return;
}
/**Other nodes**/
for(; pos > 0; pos--){
if(cursor == NULL)
return ;
cursor = cursor->next;
}
cursor->next->prev = cursor->prev;
cursor->prev->next = cursor->next;
if(cursor->content != NULL)
free(cursor->content);
free(cursor);
head->length --;
return;
}
void add(ListHead* head, void* content){
if(content == NULL) return;
/**If there is no item in the table, create the first item**/
if(head->headItem == NULL){
head->headItem = new(ListItem);
head->lastItem = head->headItem;
head->headItem->prev = NULL;
head->headItem->next = NULL;
head->headItem->content = content;
}
else{
ListItem* newItem = new(ListItem);
/** The pre-order address of the newly added item is the last item in the current list**/
newItem->prev = head->lastItem;
newItem->next = NULL;
newItem->content = content;
/**The new item becomes the last item in the list, and the last item before becomes the penultimate item**/
head->lastItem->next = newItem;
head->lastItem = newItem;
}
head->length ++;
}
void* get(ListHead* head, int pos){
ListItem *cursor = head->headItem;
for(; pos > 0; pos--){
if(cursor == NULL)
return NULL;
cursor = cursor->next;
}
return cursor->content;
}
void insert(ListHead* head, void* content, int pos){
ListItem *cursor = head->headItem;
/**If inserted into the first item**/
if(pos == 0){
if(head != NULL){
ListItem* newItem = new(ListItem);
newItem->content = content;
newItem->prev = NULL;
head->headItem->prev = newItem;
newItem->next = head->headItem;
head->headItem = newItem;
head->length ++;
return;
}
}
/** If inserted to the last item**/
if(pos == head->length - 1){
if(head != NULL){
ListItem* newItem = new(ListItem);
newItem->content = content;
newItem->next = NULL;
head->lastItem->next = newItem;
newItem->prev = head->lastItem;
head->lastItem = newItem;
head->length ++;
return;
}
}
/**other**/
for(; pos > 1; pos--){
if(cursor == NULL)
return ;
cursor = cursor->next;
}
{
ListItem* newItem = new(ListItem);
newItem->content = content;
newItem->next = cursor->next;
newItem->prev = cursor;
cursor->next->prev = newItem;
cursor->next = newItem;
head->length ++;
}
}
void destory(ListHead* head){
if(head == NULL) return;
ListItem* cursor = head->headItem;
ListItem* next = NULL;
int i=0;
while(cursor != NULL){
next = cursor->next;
if(cursor->content != NULL)
free(cursor->content);
cursor->content = NULL;
free(cursor);
cursor = NULL;
cursor = next;
//printf("clear:%d\n", i++);
}
free(head);
//printf("done\n");
}
ListHead* createList(){
ListHead* head = new(ListHead);
/**New entry has no content**/
head->headItem = NULL;
head->length = 0;
head->removeItem = removeItem;
head->removeItemByPosition = removeItemByPosition;
head->add = add;
head->get = get;
head->insert = insert;
return head;
}
Example of use:
#include "stdio.h"
#include "stdlib.h"
#include "LinkedList.h"
int main(){
int i;
ListHead* list = createList();
/**Add item display**/
for(i = 0; i < 100; i++){
int* content = new(int);
*content = i;
findMethodByObject(list, add, (void*)content);
}
/**Subtract item display**/
findMethodByObject(list, removeItem, list->headItem->next);
findMethodByObject(list, removeItem, list->headItem->next);
findMethodByObject(list, removeItem, list->lastItem);
printf("list length:%d\n", list->length);
findMethodByObject(list, removeItemByPosition, 0);
printf("list length:%d\n", list->length);
{
int* content = new(int);
*content = 9988;
findMethodByObject(list, insert, content, 90);
}
*(int*)findMethodByObject(list, get, 91) = 8899;
for(i = 0; i < list->length ; i++){
printf("%d\t", *((int*)findMethodByObject(list, get, i)));
}
destory(list);
printf("done\n");
return 0;
}
