示例#1
0
/* Stores pointer to current the entry in the provided entry structure
 * and advances the position of the iterator. Returns 1 when the current
 * entry is in fact an entry, 0 otherwise. */
int listTypeNext(listTypeIterator *li, listTypeEntry *entry) {
    /* Protect from converting when iterating */
    serverAssert(li->subject->encoding == li->encoding);

    entry->li = li;
    if (li->encoding == OBJ_ENCODING_QUICKLIST) {
        return quicklistNext(li->iter, &entry->entry);
    } else {
        serverPanic("Unknown list encoding");
    }
    return 0;
}
//将列表类型的迭代器指向的entry保存在提供的listTypeEntry结构中,并且更新迭代器,1表示成功,0失败
int listTypeNext(listTypeIterator *li, listTypeEntry *entry) {
    /* Protect from converting when iterating */
    //确保对象编码类型和迭代器中encoding成员相等
    serverAssert(li->subject->encoding == li->encoding);

    //设置listTypeEntry的entry成员关联到当前列表类型的迭代器
    entry->li = li;
    //对列表对象编码为quicklist类型操作
    if (li->encoding == OBJ_ENCODING_QUICKLIST) {
        //保存当前的entry到listTypeEntry的entry成员,并更新迭代器
        return quicklistNext(li->iter, &entry->entry);
    } else {
        serverPanic("Unknown list encoding");
    }
    return 0;
}