#include <sys/mman.h>
#include <sys/wait.h>

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


int main(int argc, char **argv, char **envp) {
	unsigned long loops;
	struct {
		unsigned long parent;
		unsigned long child;
	} *err;

	if (argc < 3) {
		printf("usage: %s LOOPS CMD [ARGS]\n", argv[0]);
		exit(1);
	}

	loops = strtoul(argv[1], NULL, 0);

	err = mmap(NULL, sizeof(*err), PROT_READ | PROT_WRITE,
	           MAP_SHARED | MAP_ANONYMOUS, -1, 0);
	if (err == MAP_FAILED) {
		printf("failed to create shared mapping (%s)\n", strerror(errno));
		exit(1);
	}

	err->parent = err->child = 0;
	while (loops--) {
		switch (fork()) {
			case 0:
				execve(argv[2], &argv[2], envp);
				err->child++;
				exit(1);
				break;

			case -1:
				err->parent++;
				break;

			default:
				wait(NULL);
		}
	}

	if (err->parent || err->child) {
		printf("fork() errors: %lu\n", err->parent);
		printf("exec() errors: %lu\n", err->child);
	}

	return 0;
}