/* Conky, a system monitor, based on torsmo
 *
 * Any original torsmo code is licensed under the BSD license
 *
 * All code written since the fork of torsmo is licensed under the GPL
 *
 * Please see COPYING for details
 *
 * Copyright (c) 2004, Hannu Saransaari and Lauri Hakkarainen
 * Copyright (c) 2005-2007 Brenden Matthews, Philip Kovacs, et. al.
 *	(see AUTHORS)
 * All rights reserved.
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 * $Id$ */

#include "conky.h"
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <fcntl.h>

/* linux */
#ifdef HAVE_SYS_STATFS_H
#include <sys/statfs.h>
#endif

/* freebsd && netbsd */
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#ifdef HAVE_SYS_MOUNT_H
#include <sys/mount.h>
#endif

#ifndef HAVE_STRUCT_STATFS_F_FSTYPENAME
#include <mntent.h>
#endif

#define MAX_FS_STATS 64

static struct fs_stat fs_stats_[MAX_FS_STATS];
struct fs_stat *fs_stats = fs_stats_;

static void update_fs_stat(struct fs_stat *fs);

void get_fs_type(const char *path, char *result);

void update_fs_stats()
{
	unsigned i;

	for (i = 0; i < MAX_FS_STATS; ++i) {
		if (fs_stats[i].set) {
			update_fs_stat(&fs_stats[i]);
		}
	}
}

void clear_fs_stats()
{
	unsigned i;
	for (i = 0; i < MAX_FS_STATS; ++i) {
		memset(&fs_stats[i], 0, sizeof(struct fs_stat));
	}
}

struct fs_stat *prepare_fs_stat(const char *s)
{
	struct fs_stat *new = 0;
	unsigned i;

	/* lookup existing or get new */
	for (i = 0; i < MAX_FS_STATS; ++i) {
		if (fs_stats[i].set) {
			if (strncmp(fs_stats[i].path, s, DEFAULT_TEXT_BUFFER_SIZE) == 0) {
				return &fs_stats[i];
			}
		} else {
			new = &fs_stats[i];
		}
	}
	/* new path */
	if (!new) {
		ERR("too many fs stats");
		return 0;
	}
	strncpy(new->path, s, DEFAULT_TEXT_BUFFER_SIZE);
	new->set = 1;
	update_fs_stat(new);
	return new;
}

static void update_fs_stat(struct fs_stat *fs)
{
	struct statfs s;

	if (statfs(fs->path, &s) == 0) {
		fs->size = (long long)s.f_blocks * s.f_bsize;
		/* bfree (root) or bavail (non-roots) ? */
		fs->avail = (long long)s.f_bavail * s.f_bsize;
		fs->free = (long long)s.f_bfree * s.f_bsize;
		get_fs_type(fs->path, fs->type);
	} else {
		fs->size = 0;
		fs->avail = 0;
		fs->free = 0;
		strncpy(fs->type, "unknown", DEFAULT_TEXT_BUFFER_SIZE);
		ERR("statfs '%s': %s", fs->path, strerror(errno));
	}
}

void get_fs_type(const char *path, char *result)
{

#ifdef HAVE_STRUCT_STATFS_F_FSTYPENAME

	struct statfs s;
	if (statfs(path, &s) == 0) {
		strncpy(result, s.f_fstypename, DEFAULT_TEXT_BUFFER_SIZE);
	} else {
		ERR("statfs '%s': %s", path, strerror(errno));
	}
	return;

#else				/* HAVE_STRUCT_STATFS_F_FSTYPENAME */

	/* TODO: walk up the directory tree so it works on on paths that are not actually mount points. */

	FILE *mtab = setmntent("/etc/mtab", "r");

	if (mtab == NULL) {
		ERR("setmntent /etc/mtab: %s", strerror(errno));
		strncpy(result, "unknown", DEFAULT_TEXT_BUFFER_SIZE);
		return;
	}

	struct mntent *me = getmntent(mtab);

	// find our path in the mtab
	while (strcmp(path, me->mnt_dir) && getmntent(mtab));

	endmntent(mtab);

	if (me && !strcmp(path, me->mnt_dir)) {
		strncpy(result, me->mnt_type, DEFAULT_TEXT_BUFFER_SIZE);
		return;
	}
#endif				/* HAVE_STRUCT_STATFS_F_FSTYPENAME */

	strncpy(result, "unknown", DEFAULT_TEXT_BUFFER_SIZE);

}