双向链表的各种操作

不用那么多废话，双向链表的插入、删除、查询等操作，欢迎大家提出修改意见:
doubleList.h

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

typedef struct Node
{
    int data;
    struct Node * next;
    struct Node * prior;
}NODE, *PNODE;

PNODE create_list(void);    //创建节点
void traverse_list(PNODE pHead);    //遍历链表（打印）
int length_list(PNODE pHead);        //求链表长度
void sort_list(PNODE pHead);        //排序
void insert_list(PNODE pHead, int val);        //插入节点
void delete_list(PNODE pHead, int pos);    //删除节点
int find_list(PNODE pHead, int val);        //查找元素


PNODE  create_list(void)  //从文件中读取数据链表的初始化值
{
       int i, len;
       int value;
       char str[10];
       FILE *pf;
       PNODE pTail, pNew;
       PNODE pHead = (PNODE)malloc(sizeof(NODE));
       if (NULL == pHead)
       {
                fprintf(stdout, "Memory molloc erroe !\n");
                exit(-1);
       }
       pTail = pHead;
       pTail->next = NULL;

       pf = fopen("./data.txt", "r");
       /*while(fgets(str, 10, pf) != NULL)
       {
           printf("str  =  %s \n", str);
       }*/
       len = 0;
       while (1)
       {
             fgets(str, 10, pf);
             if (feof(pf))
             {
                          fprintf(stdout, "file read finish !\n");
                          break;
             }
             sscanf(str, "%d", &value);
             len++;  // 记录初始化多少个节点

             pNew = (PNODE)malloc(sizeof(NODE));
             if (NULL == pNew)
             {
                      fprintf(stdout, "New Node Memory's malloc error !\n");
                      exit(-1);
             }
             /*创建一个新的节点*/
             pNew->data = value;

             pTail->next = pNew;
             pNew->prior = pTail;
             pTail = pNew;
             pTail->next = NULL;
       }
       fprintf(stdout, "Initialize %d node !\n", len);
       return pHead;
}

void traverse_list(PNODE pHead)
{
     if (NULL == pHead)
     {
              fprintf(stdout, "List is NULL !\n");
              exit(-1);
     }
     while(pHead != NULL)
     {
            printf("%d\n", pHead->data);
            pHead = pHead->next;
     }
     return;
}

int length_list(PNODE pHead)
{
    int length = 0;
    PNODE pNode = NULL;
    pNode = pHead;
    if (NULL == pNode)
    {
        fprintf(stdout, "List is NULL !\n");
        exit(-1);
    }
    while(pNode)
    {
        length++;
        pNode = pNode->next;
    }
    return length;
}

void sort_list(PNODE pHead)
{
    int length;
    int i, j;
    int tmp;
    PNODE pnode = NULL;
    PNODE qnode = NULL;
    printf("sort_list ... \n");

    if(NULL == pHead)
    {
        fprintf(stdout, "pHead is NULL !\n");
        exit(-1);
    }
    length = length_list(pHead);

    fprintf(stdout, "List Length is %d\n", length);

    for(i = 0, pnode = pHead; i < length; i++, pnode = pnode->next)
    {
        for(j = i+1, qnode = pnode->next; j < length; j++, qnode = qnode->next)
        {
            if (pnode->data > qnode->data)
            {
                tmp = pnode->data;
                pnode->data = qnode->data;
                qnode->data = tmp;
            }

        }
    }
    return;
}

void insert_list(PNODE pHead, int value)
{
    PNODE pNew;
    PNODE pTail = NULL;

    if (NULL == pHead)
    {
        fprintf(stdout, "pHead is NULL !\n");
        exit(-1);
    }

    pNew = (PNODE)malloc(sizeof(NODE));
    if (NULL == pNew)
    {
        fprintf(stdout, "in_node malloc error !\n");
        exit(-1);
    }
    memset(pNew, 0, sizeof(NODE));
    pNew->data = value;

    pTail = pHead;
    while(pTail->next != NULL)
    {
        pTail = pTail->next;
    }
    pTail->next = pNew;
    pNew->prior = pTail;
    pTail = pNew;
    pTail->next = NULL;
    fprintf(stdout, "Success insert new_node, value is %d\n", pNew->data);
    //traverse_list(pHead);
    return;
}


void delete_list(PNODE pHead, int pos)
{
    int length, i = 1;
    PNODE pDelNode = NULL;
    PNODE pPreNode = NULL;

    fprintf(stdout, "Delete node !\n");
    if (NULL == pHead)
    {
        fprintf(stdout, "pHead is NULL !\n");
        exit(-1);
    }
    length = length_list(pHead);
    if (length < pos)
    {
        fprintf(stdout, "delete's pos is error !\n");
        exit(-1);
    }
    pPreNode = pHead;
    pDelNode = pHead;
    while(pDelNode->next != NULL)
    {
        if(i == pos)
        {
            break;
        }
        i ++;
        pPreNode = pDelNode;
        pDelNode = pDelNode->next;
    }
    pPreNode->next = pDelNode->next;
    pDelNode->next->prior = pPreNode;
    free(pDelNode);
    return;
}

int find_list(PNODE pHead, int value)
{
    PNODE pFindNode = NULL;
    int pos = 1;
    if (NULL == pHead)
    {
        fprintf(stdout, "List is NULL !\n");
        exit(-1);
    }
    pFindNode = pHead;
    while(pFindNode->next != NULL)
    {
        if (pFindNode->data == value)
        {
            return pos;
        }
        pFindNode = pFindNode->next;
        pos++;
    }
}



测试文件doubleList.c

#include "../include/doubleList.h"

int main()
{
    int length;
    PNODE pHead = NULL;
    pHead = create_list();
    traverse_list(pHead);
    length = length_list(pHead);
    fprintf(stdout, "Total  %d nodes !\n", length);
    insert_list(pHead, 88);
    sort_list(pHead);
    traverse_list(pHead);
    fprintf(stdout, "Total  %d nodes !\n", length);
    delete_list(pHead, 4);
    traverse_list(pHead);
    fprintf(stdout, "Total  %d nodes !\n", length);

    fprintf(stdout, "FindPos is %d \n", find_list(pHead, 0));
    return 0;
}

其中文件中用到的data.txt数据文件只是一个简单的文件，里面包含了我初始化的一些数据项。数据格式(附件包含有程序和数据)： doubleList.rar
11
22
33
4
45
34

运行环境和命令：
Linux
gcc -g -o doubleList doublist.c