#include "config.h"
#include <stdio.h>
#include <string.h>

/**
 * crypto/hmac_sha256 - RFC2104 HMAC using SHA256.
 *
 * This code implements RFC2104, which is a fairly standard HMAC.
 *
 * License: BSD-MIT
 * Maintainer: Rusty Russell <rusty@rustcorp.com.au>
 *
 * Example:
 *	#include <ccan/crypto/hmac_sha256/hmac_sha256.h>
 *	#include <err.h>
 *	#include <stdio.h>
 *	#include <string.h>
 *
 *	// Simple demonstration: idential strings will have the same hash, but
 *	// two different strings will not.
 *	int main(int argc, char *argv[])
 *	{
 *		struct hmac_sha256 hash1, hash2;
 *
 *		if (argc != 3)
 *			errx(1, "Usage: %s <string1> <string2>", argv[0]);
 *
 *		hmac_sha256(&hash1, "key", 3, argv[1], strlen(argv[1]));
 *		hmac_sha256(&hash2, "key", 3, argv[2], strlen(argv[2]));
 *		printf("Hash is %s\n", memcmp(&hash1, &hash2, sizeof(hash1))
 *			? "different" : "same");
 *		return 0;
 *	}
 */
int main(int argc, char *argv[])
{
	/* Expect exactly one argument */
	if (argc != 2)
		return 1;

	if (strcmp(argv[1], "depends") == 0) {
		printf("ccan/crypto/sha256\n");
		return 0;
	}

	if (strcmp(argv[1], "testdepends") == 0) {
		printf("ccan/str/hex\n");
		return 0;
	}

	return 1;
}
