ntfs-3g/ntfsprogs/utils.c

429 lines
11 KiB
C

/**
* utils.c - Part of the Linux-NTFS project.
*
* Copyright (c) 2002 Richard Russon <ntfs@flatcap.org>
*
* This utility will recover deleted files from an NTFS volume.
*
* 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
*/
#include <stdio.h>
#include <stdarg.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <locale.h>
#include <libintl.h>
#include <stdlib.h>
#include <limits.h>
#include "config.h"
#include "types.h"
#include "volume.h"
#include "debug.h"
#define NTFS_TIME_OFFSET ((s64)(369 * 365 + 89) * 24 * 3600 * 10000000)
/* These utilities require the following functions */
extern int Eprintf (const char *format, ...) __attribute__ ((format (printf, 1, 2)));
extern int Vprintf (const char *format, ...) __attribute__ ((format (printf, 1, 2)));
extern int Iprintf (const char *format, ...) __attribute__ ((format (printf, 1, 2)));
/**
* utils_set_locale
*/
int utils_set_locale (void)
{
const char *locale;
locale = setlocale (LC_ALL, "");
if (!locale) {
locale = setlocale (LC_ALL, NULL);
Eprintf ("Failed to set locale, using default '%s'.\n", locale);
return 1;
} else {
Vprintf ("Using locale '%s'.\n", locale);
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;
if (stat (name, &st) == -1) {
if (errno == ENOENT) {
Eprintf ("The device %s doesn't exist\n", name);
} else {
Eprintf ("Error getting information about %s: %s\n", name, strerror (errno));
}
return 0;
}
if (!S_ISBLK (st.st_mode)) {
Vprintf ("%s is not a block device.\n", name);
if (!force) {
Eprintf ("Use the force option to work with files.\n");
return 0;
}
Vprintf ("Forced to continue.\n");
}
/* Make sure the file system is not mounted. */
if (ntfs_check_if_mounted (name, &mnt_flags)) {
Vprintf ("Failed to determine whether %s is mounted: %s\n", name, strerror (errno));
if (!force) {
Eprintf ("Use the force option to ignore this error.\n");
return 0;
}
Vprintf ("Forced to continue.\n");
} else if (mnt_flags & NTFS_MF_MOUNTED) {
Vprintf ("The device %s, is mounted.\n", name);
if (!force) {
Eprintf ("Use the force option to work a mounted filesystem.\n");
return 0;
}
Vprintf ("Forced to continue.\n");
}
return 1;
}
/**
* utils_mount_volume
*/
ntfs_volume * utils_mount_volume (const char *device, unsigned long flags, BOOL force)
{
ntfs_volume *vol;
if (!device)
return NULL;
if (!utils_valid_device (device, force))
return NULL;
vol = ntfs_mount (device, MS_RDONLY);
if (!vol) {
Eprintf ("Couldn't mount device '%s': %s\n", device, strerror (errno));
return NULL;
}
if (vol->flags & VOLUME_IS_DIRTY) {
Iprintf ("Volume is dirty.\n");
if (!force) {
Eprintf ("Run chkdsk and try again, or use the --force option.\n");
ntfs_umount (vol, FALSE);
return NULL;
}
Iprintf ("Forced to continue.\n");
}
return vol;
}
/**
* utils_parse_size - Convert a string representing a size
* @value: String to be parsed
* @size: Parsed size
* @scale: XXX FIXME
*
* 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)
return 0;
Dprintf ("Parsing size '%s'.\n", value);
result = strtoll (value, &suffix, 10);
if (result < 0 || errno == ERANGE) {
Eprintf ("Invalid size '%s'.\n", value);
return 0;
}
if (!suffix) {
Eprintf ("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:
Eprintf ("Invalid size suffix '%s'. Use T, G, M, or K.\n", suffix);
return 0;
}
} else {
if ((suffix[0] != '-') && (suffix[0] != 0)) {
Eprintf ("Invalid number '%.*s'.\n", (suffix - value + 1), value);
return 0;
}
}
Dprintf ("Parsed size = %lld.\n", result);
*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)
return 0;
middle = strchr (string, '-');
if (string == middle) {
Dprintf ("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
Dprintf ("Range has no end, defaulting to %lld.\n", b);
} else {
if (!utils_parse_size (middle+1, &b, scale))
return 0;
}
} else {
b = a;
}
Dprintf ("Range '%s' = %lld - %lld\n", string, a, b);
*start = a;
*finish = b;
return 1;
}
/**
* ntfs2utc - Convert an NTFS time to Unix time
* @time: An NTFS time in 100ns units since 1601
*
* NTFS stores times as the number of 100ns intervals since January 1st 1601 at
* 00:00 UTC. This system will not suffer from Y2K problems until ~57000AD.
*
* Return: n A Unix time (number of seconds since 1970)
*/
time_t ntfs2utc (s64 time)
{
return (time - (NTFS_TIME_OFFSET)) / 10000000;
}
/**
* utc2ntfs - convert Linux time to NTFS time
* @time: Linux time to convert to NTFS
*
* Convert the Linux time @time to its corresponding NTFS time.
*
* Linux stores time in a long at present and measures it as the number of
* 1-second intervals since 1st January 1970, 00:00:00 UTC.
*
* NTFS uses Microsoft's standard time format which is stored in a s64 and is
* measured as the number of 100 nano-second intervals since 1st January 1601,
* 00:00:00 UTC.
*
* Return: n An NTFS time (100ns units since Jan 1601)
*/
s64 utc2ntfs (time_t time)
{
/* Convert to 100ns intervals and then add the NTFS time offset. */
return (s64)time * 10000000 + NTFS_TIME_OFFSET;
}
/**
* 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)
return NULL;
if (ntfs_attr_lookup(type, NULL, 0, 0, 0, NULL, 0, ctx) != 0) {
Dprintf ("find_attribute didn't find an attribute of type: 0x%02x.\n", type);
return NULL; /* None / no more of that type */
}
Dprintf ("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)
return NULL;
ctx = ntfs_attr_get_search_ctx(NULL, mft);
if (!ctx) {
Eprintf ("Couldn't create a search context.\n");
return NULL;
}
rec = find_attribute (type, ctx);
ntfs_attr_put_search_ctx(ctx);
if (rec)
Dprintf ("find_first_attribute: found attr of type 0x%02x.\n", type);
else
Dprintf ("find_first_attribute: didn't find attr of type 0x%02x.\n", type);
return rec;
}
#if 0
hamming weight
inline unsigned int hweight32(unsigned int w)
{
unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555);
res = (res & 0x33333333) + ((res >> 2) & 0x33333333);
res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F);
res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF);
return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF);
}
inline unsigned int hweight16(unsigned int w)
{
unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555);
res = (res & 0x3333) + ((res >> 2) & 0x3333);
res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F);
return (res & 0x00FF) + ((res >> 8) & 0x00FF);
}
inline unsigned int hweight8(unsigned int w)
{
unsigned int res = (w & 0x55) + ((w >> 1) & 0x55);
res = (res & 0x33) + ((res >> 2) & 0x33);
return (res & 0x0F) + ((res >> 4) & 0x0F);
}
inline int set_bit(int nr,long * addr)
{
int mask, retval;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
retval = (mask & *addr) != 0;
*addr |= mask;
return retval;
}
inline int clear_bit(int nr, long * addr)
{
int mask, retval;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
retval = (mask & *addr) != 0;
*addr &= ~mask;
return retval;
}
inline int test_bit(int nr, long * addr)
{
int mask;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
return ((mask & *addr) != 0);
}
#endif