C 实现全类型单向链表笔记

定义

#ifndef LIST_H
#define LIST_H
#ifdef __cplusplus
extern "C" {
#endif

typedef struct ListElmt_ {
	void *data;
	struct ListElmt_ *next;
} ListElmt;

typedef struct List_ {
	int size;
	int(*match) (const void *key1, const void *key2);
	void(*destroy) (void *data);
	ListElmt *head;
	ListElmt *tail;
} List;

void list_init(List *list, void(*destroy)(void *data));
void list_destroy(List *list);
int list_ins_next(List *list, ListElmt *element, void *data);
int list_rem_next(List *list, ListElmt *element, void **data);
#define list_size(list) ((list)->size)
#define list_head(list) ((list)->head)
#define list_tail(list) ((list)->tail)
#define list_is_head(list, element) ((element) == (list)->head ? 1 : 0)
#define list_is_tail(list, element) ((element) == (list)->tail ? 1 : 0)
#define list_data(element) ((element)->data)
#define list_next(element) ((element)->next)

#ifdef __cplusplus
};
#endif
#endif

实现

#include <stdlib.h>
#include <string.h>
#include "list.h"

void list_init(List* list, void(*destroy)(void *data)) {
	list->size = 0;
	list->destroy = destroy;
	list->head = NULL;
	list->tail = NULL;
}

void list_destroy(List* list) {
	if (list != NULL) {
		void *data;
		while (list_size(list) > 0) {
			if (list_rem_next(list, NULL, &data) == 0 && list->destroy != NULL) {
				list->destroy(data);
			}
		}
		memset(list, 0, sizeof(List));
	}
}

int list_ins_next(List *list, ListElmt *element, void *data) {
	ListElmt *new_element;
	if ((new_element = (ListElmt *)malloc(sizeof(ListElmt))) == NULL) {
		return -1;
	}
	new_element->data = data;
	if (element == NULL) {
		if (list_size(list) == 0) {
			list->tail = new_element;
		}
		new_element->next = list->head;
		list->head = new_element;
	}
	else {
		if (element->next == NULL) {
			list->tail = new_element;
		}
		new_element->next = element->next;
		element->next = new_element;
	}
	list->size++;
	return 0;
}

int list_rem_next(List *list, ListElmt *element, void **data) {
	ListElmt *old_element = NULL;
	if (list == NULL || list_size(list) == 0) {
		return -1;
	}
	if (element == NULL) {
		old_element = list->head;
		*data = old_element->data;
		list->head = list->head->next;
		if (list_size(list) == 1) {
			list->tail = NULL;
		}
	}
	else {
		if (element->next != NULL) {
			old_element = element->next;
			*data = old_element->data;
			element->next = element->next->next;
			if (element->next == NULL) {
				list->tail = element;
			}
		}
	}
	free(old_element);
	list->size--;
	return 0;
}