/* Based on corrpcg.c, written in 2018 by Sebastiano Vigna (vigna@acm.org)
   adapted for SplitMix by Melissa O'Neill (oneill@acm.org)

Generates two "independent" streams using a SplitMix generator.

See <http://creativecommons.org/publicdomain/zero/1.0/>. */


#include <stdio.h>
#include <inttypes.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>

struct s_state {
	uint64_t counter;
	uint64_t gamma;
};

static inline uint64_t next(struct s_state* s) {
	uint64_t z = (s->counter += s->gamma);
	z = (z ^ (z >> 30)) * 0xbf58476d1ce4e5b9;
	z = (z ^ (z >> 27)) * 0x94d049bb133111eb;
	return z ^ (z >> 31);
}

int main(int argc, char* argv[]) {
	// Seed data fresh from /dev/random	
        struct s_state sm1 = { 0x0ad704951a71e258UL, 0x9e3779b97f4a7c15UL }; 
	// More random-looking seed data
        struct s_state sm2 = { 0xc9a6ab10c4a38a66UL, 0xdf67d33dd518d407UL };
	
	for(;;) {
	        uint64_t out = next(&sm1);
		fwrite(&out, sizeof out, 1, stdout);
		// printf("%016llx\n", out);
		out = next(&sm2);
		fwrite(&out, sizeof out, 1, stdout);
		// printf("%016llx\n", out);
	}
}