Proof-of-concept cryptocurrency miner written in C

tinyminer.c

//implements a basic proof-of-work system in C. Code by quin2

/*
note: mining in this case is pretty easy beacuse our hash algo isn't computationally intensive, plus we're not
encoding a whole lot of data
*/

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

struct block
{
	int index;
	int timestamp;
	int balence;
	int proof;
	unsigned long lasthash;
};

//encodes blocks, because C hates strings
void stringify(char *in, struct block toConvert){
	sprintf(
		in, 
		"index:%d\ntimestamp:%d\nbalence:%d\nproof:%d\nlasthash:%lu\n", 
		toConvert.index, 
		toConvert.timestamp, 
		toConvert.balence,
		toConvert.proof,
		toConvert.lasthash
	);
}

//handles string hashing
unsigned long hash(unsigned char *str) {
    unsigned long hash = 5381;
    int c;

    while ((c = *str++))
        hash = ((hash << 5) + hash) + c; /* hash * 33 + c */

    return hash;
}


//finds proof nonce so hash will end with 00000
int findProof(struct block toMine){
	toMine.proof = 0;

	while(1){

		//check for valid proof

		char mid1[150];
		stringify(mid1, toMine);
		unsigned char *mid = (unsigned char*)mid1;
		unsigned long guess = hash(mid);

		//check for trailing 0's...
		int sum = 0, resid = 1;
		for(int i = 0; i < 6; i++){
			if((guess / resid) % 10 == 0) sum++;
			resid = resid * 10;
		}
		if(sum == 5) break;

		toMine.proof = toMine.proof + 1;
	}

	return toMine.proof;
}

int main(int argc, char *argv[]){
	//fake 'genesis' block
	struct block myBlock;
	unsigned long last = 15591343936234076685U;
	myBlock.index = 0; myBlock.timestamp = 1557014863; myBlock.balence = 50; myBlock.proof = 0; myBlock.lasthash = last;

	int answer = findProof(myBlock);

	printf("%d\n", answer);

	return 0;
}