c语言单链表

/*linklist.h*/
#ifndef LINKLIST_H
#define LINKLIST_H
//定义节点指针
typedef struct node *link;
//节点数据结构
struct node {
    unsigned char item;
    link next;
};
//创建节点
link make(unsigned char item);
//释放节点内存
void free_node(link);
//查找节点
link search(unsigned char);
//删除节点
void delete(link);
//执行回调函数
void traverse(void (*visit)(link));
//销毁链表
void destroy(void);
//压入
void push(link);
//弹出
link pop(void);
#endif

/*linklist.c*/
#include <stdio.h>
#include <stdlib.h>
#include "linklist.h"
static link head = NULL;
/**
 * 功能：创建节点
 * return：link
 */
link make_node(unsigned char item)
{
    //分配内存
    link p = malloc(sizeof *p);
    p->item = item;
    p->next = NULL;
    return p;
}

/**
 * 功能：释放节点内存
 * return：void
 */
void free_node(link p)
{
    free(p);
}

/**
 * 功能：查找节点
 * return：link
 */
link search(unsigned char key)
{
    link p;
    for(p = head; p; p = p->next) {
        if(p->item == key){
            return p;
        }
    }
    return NULL;
}

/**
 * 功能：插入节点
 * return：void
 */
void insert(link p)
{
    p->next = head;
    head = p;
}
 
/**
 * 功能：删除节点
 * return：void
 */
void delete(link p)
{
    link pre;
    if (p == head) {
        head = p->next;
        return;
    }
    for (pre = head; pre; pre = pre->next)
    {
        if(pre->next == p) {
            pre->next = p->next;
            return;
        }
    }
}

/**
 * 功能：执行回调函数
 * return：void
 */
void traverse(void (*visit)(link))
{
    link p;
    for (p = head; p; p = p->next)
    {
         visit(p);
    }
   
}

/**
 * 功能：销毁链表
 * return：void
 */
void destroy(void)
{
    link q,p;
    p = head;
    head = NULL;
    while (p)
    {
        q = p;
        p = p->next;
        free_node(q);
    }
}

/**
 * 功能：压入
 * return：void
 */
void push(link p)
{
    insert(p);
}

/**
 * 功能：弹出
 * return：void
 */
link pop(void)
{
    if(head == NULL){
        return NULL;
    } else {
        link p = head;
        head = head->next;
        return p;
    }
}

#include <stdio.h>
#include "linklist.h"
void print_item (link p)
{
    printf("%d\n",p->item);
}
int main()
{
    link p = make_node(10);
    insert(p);
    p = make_node(5);
    insert(p);
    p = make_node(90);
    insert(p);
    delete(p);
    free_node(p);
    traverse(print_item);
    destroy();
    return 1;
}