/*
 *  GEM MINE - The ROCK Linux Package Manager
 *  Copyright (C) 2002-2005 Clifford Wolf
 *  
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#include "md5sum.h"
#include "memdb.h"

struct memdb_t md5_memdb;
int md5_memdb_filled;

/* This function is defined in md5.c (which is from GNU textutils 2.0) */
extern char * md5_file(const char *filename);

char * md5sum_create(char * root, char * filename) {
	char realfilename[1024];
	struct stat statbuf;

	snprintf(realfilename, 1024, "%s/%s", root, filename);
	if (lstat(realfilename, &statbuf) != 0 || S_ISDIR(statbuf.st_mode))
		return "";
	else if (!S_ISREG(statbuf.st_mode))
		return "X";
	else
		return md5_file(realfilename);
}

/* Returns if file is unmodified, modified, duplicate, or shared. */
int md5sum_check(char * root, char * filename)
{
	char *md5_f, *md5_d;

	md5_f = md5sum_create(root, filename);
	md5_d = memdb_get(&md5_memdb, filename);

/*	printf ("md5sum_check(): md5_f: %s, md5_d: %s\n",
		(md5_f) ? md5_f : "NULL", (md5_d) ? md5_d : "NULL");
*/	
	if (strcmp(md5_f, "") == 0)
		return MD5SUM_CHECK_OK;
	else if (md5_d == NULL)
		return MD5SUM_CHECK_DUPLICATE;
	else if (strcmp(md5_f, md5_d) == 0 || strcmp(md5_d, "X") == 0)
		return MD5SUM_CHECK_OK;
	else if (strcmp(md5_d, "Duplicate entry") == 0)
		return MD5SUM_CHECK_SHARED;
	else
		return MD5SUM_CHECK_MODIFIED;
}

void md5sum_initdb(char * root, int verbose)
{
	struct dirent *md5_dent;
	char buffer[1024];
	char *md5sum, *filename;
	FILE *f;
	DIR *d;

	if ( md5_memdb_filled ) return;

	snprintf(buffer, 1024, "%s/var/adm/md5sums", root);
	if ( (d = opendir(buffer)) == NULL ) return;
	if (verbose) printf("Reading MD5 checksum database into memory ...\n");
	memdb_init(&md5_memdb);

	while ( (md5_dent = readdir(d)) != NULL ) {
		snprintf(buffer, 1024, "%s/var/adm/md5sums/%s",
		                       root, md5_dent->d_name);
		f = fopen(buffer, "r");
		if ( f != NULL ) {
			while (fgets(buffer, 1024, f) != NULL) {
				md5sum = strtok(buffer, " \t\n");
				filename = strtok(NULL, "\n");
				if ( md5sum && filename) {
					while ( *filename == ' ' ) filename++;
					memdb_put(&md5_memdb, filename, md5sum);
				}
			}
			fclose(f);
		}
	}
	closedir(d);

	md5_memdb_filled = 1;
}