utils.c

一个在linux下挂载ntfs文件系统的好工具

/**
 * utils.c - Part of the Linux-NTFS project.
 *
 * Copyright (c) 2002-2005 Richard Russon
 * Copyright (c) 2003-2006 Anton Altaparmakov
 * Copyright (c) 2003 Lode Leroy
 *
 * A set of shared functions for ntfs utilities
 *
 * 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 (in the main directory of the Linux-NTFS
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef HAVE_STDARG_H
#include <stdarg.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_LOCALE_H
#include <locale.h>
#endif
#ifdef HAVE_LIBINTL_H
#include <libintl.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#ifdef HAVE_CTYPE_H
#include <ctype.h>
#endif

#include "utils.h"
#include "types.h"
#include "volume.h"
#include "debug.h"
#include "dir.h"
#include "version.h"
#include "logging.h"
#include "misc.h"

const char *ntfs_bugs = "Developers' email address: "NTFS_DEV_LIST"\n";
const char *ntfs_home = "Linux NTFS homepage: http://www.linux-ntfs.org\n";
const char *ntfs_gpl = "This program is free software, released under the GNU "
	"General Public License\nand you are welcome to redistribute it under "
	"certain conditions.  It comes with\nABSOLUTELY NO WARRANTY; for "
	"details read the GNU General Public License to be\nfound in the file "
	"\"COPYING\" distributed with this program, or online at:\n"
	"http://www.gnu.org/copyleft/gpl.html\n";

/**
 * utils_set_locale
 */
int utils_set_locale(void)
{
	const char *locale;

	locale = setlocale(LC_ALL, "");
	if (!locale) {
		locale = setlocale(LC_ALL, NULL);
		ntfs_log_error("Couldn't set local environment, using default '%s'.\n", locale);
		return 1;
	} else {
		return 0;
	}
}

/**
 * utils_valid_device - Perform some safety checks on the device, before we start
 * @name:   Full pathname of the device/file to work with
 * @force:  Continue regardless of problems
 *
 * Check that the name refers to a device and that is isn't already mounted.
 * These checks can be overridden by using the force option.
 *
 * Return:  1  Success, we can continue
 *	    0  Error, we cannot use this device
 */
int utils_valid_device(const char *name, int force)
{
	unsigned long mnt_flags = 0;
	struct stat st;

#ifdef __CYGWIN32__
	/* FIXME: This doesn't work for Cygwin, so just return success for now... */
	return 1;
#endif
	if (!name) {
		errno = EINVAL;
		return 0;
	}

	if (stat(name, &st) == -1) {
		if (errno == ENOENT) {
			ntfs_log_error("The device %s doesn't exist\n", name);
		} else {
			ntfs_log_perror("Error getting information about %s", name);
		}
		return 0;
	}

	if (!S_ISBLK(st.st_mode) && !S_ISREG(st.st_mode)) {
		ntfs_log_warning("%s is not a block device, "
				 "nor regular file.\n", name);
		if (!force) {
			ntfs_log_error("Use the force option to work with other"
				       " file types, for your own risk!\n");
			return 0;
		}
		ntfs_log_warning("Forced to continue.\n");
	}

	/* Make sure the file system is not mounted. */
	if (ntfs_check_if_mounted(name, &mnt_flags)) {
		ntfs_log_perror("Failed to determine whether %s is mounted", name);
		if (!force) {
			ntfs_log_error("Use the force option to ignore this error.\n");
			return 0;
		}
		ntfs_log_warning("Forced to continue.\n");
	} else if (mnt_flags & NTFS_MF_MOUNTED) {
		ntfs_log_warning("The device %s, is mounted.\n", name);
		if (!force) {
			ntfs_log_error("Use the force option to work a mounted filesystem.\n");
			return 0;
		}
		ntfs_log_warning("Forced to continue.\n");
	}

	return 1;
}

/**
 * utils_mount_volume - Mount an NTFS volume
 */
ntfs_volume * utils_mount_volume(const char *device, unsigned long flags, BOOL force)
{
	ntfs_volume *vol;

	if (!device) {
		errno = EINVAL;
		return NULL;
	}

	if (!utils_valid_device(device, force))
		return NULL;

	vol = ntfs_mount(device, flags);
	if (!vol) {
		ntfs_log_perror("Couldn't mount device '%s'", device);
		if (errno == EPERM)
			ntfs_log_error("Windows was hibernated.  Try to mount "
					"volume in windows, shut down and try "
					"again.\n");
		if (errno == EOPNOTSUPP)
			ntfs_log_error("Windows did not shut down properly.  "
					"Try to mount volume in windows, "
					"shut down and try again.\n");
		return NULL;
	}

	if (vol->flags & VOLUME_IS_DIRTY) {
		ntfs_log_warning("Volume is dirty.\n");
		if (!force) {
			ntfs_log_error("Run chkdsk and try again, or use the "
					"force option.\n");
			ntfs_umount(vol, FALSE);
			return NULL;
		}
		ntfs_log_warning("Forced to continue.\n");
	}

	return vol;
}

/**
 * utils_parse_size - Convert a string representing a size
 * @value:  String to be parsed
 * @size:   Parsed size
 * @scale:  Whether or not to allow a suffix to scale the value
 *
 * Read a string and convert it to a number.  Strings may be suffixed to scale
 * them.  Any number without a suffix is assumed to be in bytes.
 *
 * Suffix  Description  Multiple
 *  [tT]    Terabytes     10^12
 *  [gG]    Gigabytes     10^9
 *  [mM]    Megabytes     10^6
 *  [kK]    Kilobytes     10^3
 *
 * Notes:
 *     Only the first character of the suffix is read.
 *     The multipliers are decimal thousands, not binary: 1000, not 1024.
 *     If parse_size fails, @size will not be changed
 *
 * Return:  1  Success
 *	    0  Error, the string was malformed
 */
int utils_parse_size(const char *value, s64 *size, BOOL scale)
{
	long long result;
	char *suffix = NULL;

	if (!value || !size) {
		errno = EINVAL;
		return 0;
	}

	result = strtoll(value, &suffix, 0);
	if (result < 0 || errno == ERANGE) {
		ntfs_log_error("Invalid size '%s'.\n", value);
		return 0;
	}

	if (!suffix) {
		ntfs_log_error("Internal error, strtoll didn't return a suffix.\n");
		return 0;
	}

	if (scale) {
		switch (suffix[0]) {
			case 't': case 'T': result *= 1000;
			case 'g': case 'G': result *= 1000;
			case 'm': case 'M': result *= 1000;
			case 'k': case 'K': result *= 1000;
			case '-': case 0:
				break;
			default:
				ntfs_log_error("Invalid size suffix '%s'.  Use T, G, M, or K.\n", suffix);
				return 0;
		}
	} else {
		if ((suffix[0] != '-') && (suffix[0] != 0)) {
			ntfs_log_error("Invalid number '%.*s'.\n", (int)(suffix - value + 1), value);
			return 0;
		}
	}

	*size = result;
	return 1;
}

/**
 * utils_parse_range - Convert a string representing a range of numbers
 * @string:  The string to be parsed
 * @start:   The beginning of the range will be stored here
 * @finish:  The end of the range will be stored here
 *
 * Read a string of the form n-m.  If the lower end is missing, zero will be
 * substituted.  If the upper end is missing LONG_MAX will be used.  If the
 * string cannot be parsed correctly, @start and @finish will not be changed.
 *
 * Return:  1  Success, a valid string was found
 *	    0  Error, the string was not a valid range
 */
int utils_parse_range(const char *string, s64 *start, s64 *finish, BOOL scale)
{
	s64 a, b;
	char *middle;

	if (!string || !start || !finish) {
		errno = EINVAL;
		return 0;
	}

	middle = strchr(string, '-');
	if (string == middle) {
		ntfs_log_debug("Range has no beginning, defaulting to 0.\n");
		a = 0;
	} else {
		if (!utils_parse_size(string, &a, scale))
			return 0;
	}

	if (middle) {
		if (middle[1] == 0) {
			b = LONG_MAX;		// XXX ULLONG_MAX
			ntfs_log_debug("Range has no end, defaulting to %lld.\n", b);
		} else {
			if (!utils_parse_size(middle+1, &b, scale))
				return 0;
		}
	} else {
		b = a;
	}

	ntfs_log_debug("Range '%s' = %lld - %lld\n", string, a, b);

	*start  = a;
	*finish = b;
	return 1;
}

/**
 * find_attribute - Find an attribute of the given type
 * @type:  An attribute type, e.g. AT_FILE_NAME
 * @ctx:   A search context, created using ntfs_get_attr_search_ctx
 *
 * Using the search context to keep track, find the first/next occurrence of a
 * given attribute type.
 *
 * N.B.  This will return a pointer into @mft.  As long as the search context
 *       has been created without an inode, it won't overflow the buffer.
 *
 * Return:  Pointer  Success, an attribute was found
 *	    NULL     Error, no matching attributes were found
 */
ATTR_RECORD * find_attribute(const ATTR_TYPES type, ntfs_attr_search_ctx *ctx)
{
	if (!ctx) {
		errno = EINVAL;
		return NULL;
	}

	if (ntfs_attr_lookup(type, NULL, 0, 0, 0, NULL, 0, ctx) != 0) {
		ntfs_log_debug("find_attribute didn't find an attribute of type: 0x%02x.\n", type);
		return NULL;	/* None / no more of that type */
	}

	ntfs_log_debug("find_attribute found an attribute of type: 0x%02x.\n", type);
	return ctx->attr;
}

/**
 * find_first_attribute - Find the first attribute of a given type
 * @type:  An attribute type, e.g. AT_FILE_NAME
 * @mft:   A buffer containing a raw MFT record
 *
 * Search through a raw MFT record for an attribute of a given type.
 * The return value is a pointer into the MFT record that was supplied.
 *
 * N.B.  This will return a pointer into @mft.  The pointer won't stray outside
 *       the buffer, since we created the search context without an inode.
 *
 * Return:  Pointer  Success, an attribute was found
 *	    NULL     Error, no matching attributes were found
 */
ATTR_RECORD * find_first_attribute(const ATTR_TYPES type, MFT_RECORD *mft)
{
	ntfs_attr_search_ctx *ctx;
	ATTR_RECORD *rec;

	if (!mft) {
		errno = EINVAL;
		return NULL;
	}

	ctx = ntfs_attr_get_search_ctx(NULL, mft);
	if (!ctx) {
		ntfs_log_error("Couldn't create a search context.\n");
		return NULL;
	}

	rec = find_attribute(type, ctx);
	ntfs_attr_put_search_ctx(ctx);
	if (rec)
		ntfs_log_debug("find_first_attribute: found attr of type 0x%02x.\n", type);
	else
		ntfs_log_debug("find_first_attribute: didn't find attr of type 0x%02x.\n", type);
	return rec;
}

/**
 * utils_inode_get_name
 *
 * using inode
 * get filename
 * add name to list
 * get parent
 * if parent is 5 (/) stop
 * get inode of parent
 */
int utils_inode_get_name(ntfs_inode *inode, char *buffer, int bufsize)
{
	// XXX option: names = posix/win32 or dos
	// flags: path, filename, or both
	const int max_path = 20;

	ntfs_volume *vol;
	ntfs_attr_search_ctx *ctx;
	ATTR_RECORD *rec;
	FILE_NAME_ATTR *attr;
	int name_space;
	MFT_REF parent = FILE_root;
	char *names[max_path + 1];// XXX ntfs_malloc? and make max bigger?
	int i, len, offset = 0;

	if (!inode || !buffer) {
		errno = EINVAL;
		return 0;
	}

	vol = inode->vol;

	//ntfs_log_debug("sizeof(char*) = %d, sizeof(names) = %d\n", sizeof(char*), sizeof(names));
	memset(names, 0, sizeof(names));

	for (i = 0; i < max_path; i++) {

		ctx = ntfs_attr_get_search_ctx(inode, NULL);
		if (!ctx) {
			ntfs_log_error("Couldn't create a search context.\n");
			return 0;
		}

		//ntfs_log_debug("i = %d, inode = %p (%lld)\n", i, inode, inode->mft_no);

		name_space = 4;
		while ((rec = find_attribute(AT_FILE_NAME, ctx))) {
			/* We know this will always be resident. */
			attr = (FILE_NAME_ATTR *) ((char *) rec + le16_to_cpu(rec->value_offset));

			if (attr->file_name_type > name_space) { //XXX find the ...
				continue;
			}

			name_space = attr->file_name_type;
			parent     = le64_to_cpu(attr->parent_directory);

			if (names[i]) {
				free(names[i]);
				names[i] = NULL;
			}

			if (ntfs_ucstombs(attr->file_name, attr->file_name_length,
			    &names[i], 0) < 0) {
				char *temp;
				ntfs_log_error("Couldn't translate filename to current locale.\n");
				temp = ntfs_malloc(30);
				if (!temp)
					return 0;
				snprintf(temp, 30, "<MFT%llu>", (unsigned
						long long)inode->mft_no);
				names[i] = temp;
			}

			//ntfs_log_debug("names[%d] %s\n", i, names[i]);
			//ntfs_log_debug("parent = %lld\n", MREF(parent));
		}

		ntfs_attr_put_search_ctx(ctx);

		if (i > 0)			/* Don't close the original inode */
			ntfs_inode_close(inode);

		if (MREF(parent) == FILE_root) {	/* The root directory, stop. */
			//ntfs_log_debug("inode 5\n");
			break;
		}

		inode = ntfs_inode_open(vol, parent);
		if (!inode) {
			ntfs_log_error("Couldn't open inode %llu.\n",
					(unsigned long long)MREF(parent));
			break;
		}
	}

	if (i >= max_path) {
		/* If we get into an infinite loop, we'll end up here. */
		ntfs_log_error("The directory structure is too deep (over %d) nested directories.\n", max_path);
		return 0;
	}

	/* Assemble the names in the correct order. */
	for (i = max_path; i >= 0; i--) {
		if (!names[i])
			continue;