memusage dat parser

parse_mem_dat.c

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

struct entry {
	uint64_t heap;
	uint64_t stack;
	uint32_t time_low;
	uint32_t time_high;
};

int main(void)
{
	FILE *f = fopen("mem.dat", "r");
	if (f == NULL) {
		fprintf(stderr, "%s:%i: open error\n", __FILE__, __LINE__);
		exit(EXIT_FAILURE);
	}

	FILE *of = fopen("mem.txt", "w");
	if (of == NULL) {
		fprintf(stderr, "%s:%i: open error\n", __FILE__, __LINE__);
		exit(EXIT_FAILURE);
	}

	struct entry e, h1, h2;

	int nread = fread(&h1, sizeof(struct entry), 1, f);
	if (nread != 1) {
		printf("got %i bytes, halting\n", nread);
		exit(EXIT_FAILURE);
	}
	nread = fread(&h2, sizeof(struct entry), 1, f);
	if (nread != 1) {
		printf("got %i bytes, halting\n", nread);
		exit(EXIT_FAILURE);
	}

	uint64_t start_time = ((uint64_t) h1.time_high) << 32 | h1.time_low;
	uint64_t end_time = ((uint64_t) h2.time_high) << 32 | h2.time_low;
	uint64_t total_time = end_time - start_time;

	while (1) {
		nread = fread(&e, sizeof(struct entry), 1, f);
		if (nread != 1) {
			printf("got %i bytes, halting\n", nread);
			break;
		}

		uint64_t now = ((uint64_t) e.time_high) << 32 | e.time_low;
		double t = ((double)now - (double)start_time) / (double)total_time;
		printf("heap: %lu, stack: %lu, time: %lf\n", e.heap, e.stack, t);

		fprintf(of, "%lf\t%lu\t%lu\n", t, e.heap, e.stack);
	}

	fclose(of);
	fclose(f);

	return 0;
}