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

#include "md5/global.h"
#include "md5/md5.h"

#include "base64.h"
#include "md5.h"
#include "error.h"

#undef MD5_SHOW_ERRORS


/* md5_digest_file - Calculate MD5 digest of a file.
 *
 * Args:
 *     path - Path of file to hash.
 *
 * Returns:
 *     string containing the digest on success, "" on failure
 */
char *md5_digest_file(const char *path) {
	unsigned char    c[MD5_DIGEST_LENGTH];
	FILE            *fp;
	int              bytes;
	unsigned char    data[1024 * 64];
	static char      digest[MD5_DIGEST_LENGTH * 2 + 1];
	MD5_CTX          context;

	fp = fopen(path, "rb");
	if (fp == NULL) {
#ifdef MD5_SHOW_ERRORS
		error("md5_digest_file: unable to open %s for reading: %s",
			  path,
			  strerror(errno));
#endif /* MD5_SHOW_ERRORS */
		return NULL;
	}

	MD5Init(&context);
	while ((bytes = fread(data, 1, sizeof(data), fp)) != 0)
		MD5Update(&context, data, bytes);
	MD5Final(c, &context);

	fclose(fp);

	snprintf(digest, sizeof(digest),
			 "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
			 c[0], c[1], c[2], c[3], c[4],
			 c[5], c[6], c[7], c[8], c[9],
			 c[10], c[11], c[12], c[13], c[14],
			 c[15]);

	return digest;
}