#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>

#include "util.h"

int vasprintf(char **dest, const char *fmt, va_list ap) {
	assert(*dest == NULL);
	char *buf = NULL; size_t len, size;
	va_list ap2;

	size = 4096;
	buf = malloc(size);

	va_copy(ap2, ap);
	len = vsnprintf(buf, size, fmt, ap);
	va_end(ap);

	if (len >= size) {
		size = len + 1;
		buf = realloc(buf, size);
		va_copy(ap2, ap);
		len = vsnprintf(buf, size, fmt, ap);
		va_end(ap2);
	}
	if (len < 0 || len >= size) {
		fprintf(stderr, "asprintf: failed to format buffer");
		free(buf);
		exit(EXIT_FAILURE);
	}

	*dest = buf;
	return len;
}

int asprintf(char **dest, const char *fmt, ...) {
	va_list ap;
	int ret;
	va_start(ap, fmt);
	ret = vasprintf(dest, fmt, ap);
	va_end(ap);
	return ret;
}

size_t hash(const char *str, int max_val) {
	size_t ret = 0;

	for (const char *p = str; *p != '\0'; p++) {
		ret += (size_t)*p + ((size_t)*p << 6) + ((size_t)*p << 16);
	}

	ret = ret % max_val;

	return ret;
}