双向循环链表（C语言描述）（五）

代码清单

// dictionary.h
#ifndef __DICTIONARY_H__
#define __DICTIONARY_H__

#include <assert.h>
#include <stdio.h>
#include <stdio_ext.h>

#include "mystring.h"
#include "linkedlist.h"

void dict_init();
void dict_show();

#endif // __DICTIONARY_H__

// dictionary.c
#include "dictionary.h"
#define PATH "dictionary.dat"

LinkedList list;
static void dict_load();
static void dict_store();
void dict_search(const char * eng);
void dict_add(const char * eng);
void dict_delete();
void dict_modify();
int dict_cmp(const void * s1, const void * s2);

void dict_init() {
    list = linkedlist_new();

    dict_load();
    printf("Welcome.");
}

void dict_show() {
    while (1) {
        string str;
        printf("
>");
        mygets(str);

        if (!strcmp(str, "quit;")) {
            dict_store();
            linkedlist_destory(&list);
            printf("Bye.
");
            return;
        } else if (!strcmp(str, "delete;")) {
            dict_delete();
        } else if (!strcmp(str, "modify;")) {
            dict_modify();
        } else {
            dict_search(str);
        }
    }
}

static void dict_load() {
    FILE * fp;
    struct Word word;

    while (!(fp = fopen(PATH, "rb"))) {
        fp = fopen(PATH, "wb");
        fclose(fp);
    }
    assert(fp);

    fread(&word, sizeof(struct Word), 1, fp);
    while (!feof(fp)) {
        linkedlist_insert(list, TRAVELDIR_BACKWARD, 1, word);
        fread(&word, sizeof(struct Word), 1, fp);
    }

    fclose(fp);
}

static void dict_store() {
    FILE * fp;
    const int count = linkedlist_length(list);

    assert(fp = fopen(PATH, "wb"));
    for (int i = 0; i < count; i++) {
        fwrite(linkedlist_get(list, TRAVELDIR_FORWARD, i + 1),
                sizeof(struct Word), 1, fp);
    }

    fclose(fp);
}

int dict_cmp(const void * s1, const void * s2) {
    return strcmp(((LinkedListData *) s1)->eng, ((LinkedListData *) s2)->eng);
}

void dict_search(const char * eng) {
    int location;
    struct Word word;
    strcpy(word.eng, eng);

    if ((location = linkedlist_locate(list, TRAVELDIR_FORWARD, word, dict_cmp))
            == -1) {    // not found
        dict_add(eng);
    } else {            // found
        printf("%s
", linkedlist_get(list, TRAVELDIR_FORWARD, location)->chn);
    }
}

void dict_add(const char * eng) {
    struct Word word;
    strcpy(word.eng, eng);

    printf("The word does not exist, add it?
y/n>");
    if (__fpurge(stdin), getchar() == 'y') {
        printf("Ok, what does it mean?
>");
        mygets(word.chn);

        linkedlist_insert(list, TRAVELDIR_BACKWARD, 1, word);
        printf("The word is existed now.
");
    }
}

void dict_delete() {
    int location;
    struct Word word;

    printf("What word do you wanna delete?
>");
    mygets(word.eng);

    if ((location = linkedlist_locate(list, TRAVELDIR_FORWARD, word, dict_cmp))
            != -1) {    // found
        struct Word * pWord = linkedlist_get(list, TRAVELDIR_FORWARD, location);

        printf("Delete: %s %s
Are you sure?
y/n>", pWord->eng, pWord->chn);
        if (__fpurge(stdin), getchar() == 'y') {
            linkedlist_delete(list, TRAVELDIR_FORWARD, location);
            printf("The word is deleted now.
");
        }
    } else {            // not found
        printf("The word does not exist.
");
    }
}

void dict_modify() {
    int location;
    struct Word word;

    printf("What word do you wanna modify?
>");
    mygets(word.eng);

    if ((location = linkedlist_locate(list, TRAVELDIR_FORWARD, word, dict_cmp))
            != -1) {    // found
        struct Word * pWord = linkedlist_get(list, TRAVELDIR_FORWARD, location);

        printf("Ok, what does it mean?
>");
        mygets(pWord->chn);
        printf("The word is modified now.
");
    } else {            // not found
        printf("The word does not exist.
");
    }
}

// mystring.h
#ifndef __MYSTRING_H__
#define __MYSTRING_H__

#include <stdio.h>
#include <stdio_ext.h>

#define MAX_STR_LEN 8
typedef char string[MAX_STR_LEN];

void mygets(char * s);

#endif // __MYSTRING_H__

// mystring.c
#include "mystring.h"

void mygets(char * s)
{
    __fpurge(stdin);
    fgets(s, MAX_STR_LEN, stdin);
    while (*s++) {
        *s = *s == '
' ? 0 : *s;
    }
}

// main.c
#include "dictionary.h"

int main()
{
    dict_init();
    dict_show();
    
    return 0;
}