hash - C - operations on bits representing a structure -


i'm trying write hashset in c, , i've found 1 hash function, hashes according bits in data. have following structure:

struct triple {     int a;     int b;     int c; };

the question - how bit representation object of type struct triple? let's want xor bits 8-bit integer. how that?

iterate on bytes of struct , xor each 1 individually, e.g.,

void bytexor(unsigned char xor_byte, void *data, size_t size) {     unsigned char *p = data;     while (size--) {         *p++ ^= xor_byte;     } }

usage be:

struct triple my_struct; // ... bytexor(0xff, &my_struct, sizeof my_struct);

(note: answers question of how xor struct byte. implementing general hash function based on this, may not particularly idea since struct may have padding, i.e., bytes potentially non-deterministic values unrelated values of actual payload fields.)


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