关于胖指针的应用

unsigned int mystrlen(char* str) {    unsigned int c;    for (c = 0; *str != '\0'; c++, *str++);    return c;}

typedef struct redisObject {
    //对象的数据类型，字符串对象应该为 OBJ_STRING
    unsigned type:4;        
    //对象的编码类型，分别为OBJ_STRING、OBJ_ENCODING_INT或OBJ_ENCODING_EMBSTR
    unsigned encoding:4;
    //LRU_BITS为24位，最近一次的访问时间
    unsigned lru:LRU_BITS; /* lru time (relative to server.lruclock) */
    //引用计数
    int refcount;
    //指向底层数据实现的指针
    void *ptr;
} robj;