如何将long unsigned转换为unsigned char*？

Question

我试图哈希一个unsigned long值,但哈希函数需要一个unsigned char *,如下面的实现中所示:

unsigned long djb2(unsigned char *key, int n)
{
    unsigned long hash = 5381;
    int i = 0;
    while (i < n-8) {
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
        hash = hash * 33 + key[i++];
    }
    while (i < n)
        hash = hash * 33 + key[i++];
    return hash;
}

有没有办法实现我的目标,也许是两者之间的演员？

Answer 1

unsigned long x;

unsigned char * p = (unsigned char*)&x;

确保在系统中使用全部4个字节p,或者unsigned long系统的长度.