getlabel.ntfs.c

linux下的一个mount工具

/*
 *  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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
 * $Id: getlabel.ntfs.c,v 1.1.1.1 2000/09/13 19:36:45 lyonel Exp $
 *
 * Copyright (c) 2000, Lyonel VINCENT <[e-mail]>
 *
 */

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdint.h>

/* p is supposed to be a char*, unsigned char* or uint8_t* */

#define NTFS_GETU8(p)	((uint8_t*)p[0])
#define NTFS_GETS8(p)	((int8_t*)p[0])
#define NTFS_GETU16(p)	((uint16_t)NTFS_GETU8(p)+(uint16_t)NTFS_GETU8(p+1)<<8)
#define NTFS_GETS16(p)	((int16_t)NTFS_GETS8(p)+(int16_t)NTFS_GETS8(p+1)<<8)
#define NTFS_GETU32(p)	((uint32_t)NTFS_GETU16(p)+(uint32_t)NTFS_GETU16(p+2))
#define NTFS_GETU64(p)	((uint64_t)NTFS_GETU32(p)+(uint64_t)NTFS_GETU32(p+4))

#define NTFS_MAGIC	"NTFS"

#define BLOCKSIZE	512

int ntfs_getlabel(int fd, char *label)
{
	char buffer[1024];
	
	if (lseek(fd, 0, SEEK_SET) != 0
	    || read(fd, buffer, sizeof(buffer)) != sizeof(buffer)
	    || (strncmp(buffer+3, NTFS_MAGIC, strlen(NTFS_MAGIC)) != 0))
		return 0;

	strcpy(label, "");
	return 1;
}