/**
 * ntfsfix - Part of the Linux-NTFS project.
 *
 * Copyright (c) 2000-2006 Anton Altaparmakov
 * Copyright (c) 2002-2006 Szabolcs Szakacsits
 * Copyright (c) 2007      Yura Pakhuchiy
 * Copyright (c) 2011      Jean-Pierre Andre
 *
 * This utility fixes some common NTFS problems, resets the NTFS journal file
 * and schedules an NTFS consistency check for the first boot into Windows.
 *
 *	Anton Altaparmakov <aia21@cantab.net>
 *
 * 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 source
 * in the file COPYING); if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/*
 * WARNING: This program might not work on architectures which do not allow
 * unaligned access. For those, the program would need to start using
 * get/put_unaligned macros (#include <asm/unaligned.h>), but not doing it yet,
 * since NTFS really mostly applies to ia32 only, which does allow unaligned
 * accesses. We might not actually have a problem though, since the structs are
 * defined as being packed so that might be enough for gcc to insert the
 * correct code.
 *
 * If anyone using a non-little endian and/or an aligned access only CPU tries
 * this program please let me know whether it works or not!
 *
 *	Anton Altaparmakov <aia21@cantab.net>
 */

#include "config.h"

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STDIO_H
#include <stdio.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif

#include "types.h"
#include "attrib.h"
#include "volume.h"
#include "bootsect.h"
#include "mft.h"
#include "device.h"
#include "logfile.h"
#include "utils.h"
/* #include "version.h" */
#include "logging.h"
#include "misc.h"

#ifdef NO_NTFS_DEVICE_DEFAULT_IO_OPS
#	error "No default device io operations!  Cannot build ntfsfix.  \
You need to run ./configure without the --disable-default-device-io-ops \
switch if you want to be able to build the NTFS utilities."
#endif

static const char *EXEC_NAME = "ntfsfix";
static const char OK[]       = "OK\n";
static const char FAILED[]   = "FAILED\n";

#define DEFAULT_SECTOR_SIZE 512

static struct {
	char *volume;
	BOOL no_action;
} opt;

/**
 * usage
 */
__attribute__((noreturn))
static void usage(void)
{
	ntfs_log_info("%s v%s (libntfs-3g)\n"
		   "\n"
		   "Usage: %s [options] device\n"
		   "    Attempt to fix an NTFS partition.\n"
		   "\n"
		   "    -h, --help             Display this help\n"
		   "    -n, --no-action        Do not write anything\n"
		   "    -V, --version          Display version information\n"
		   "\n"
		   "For example: %s /dev/hda6\n\n",
		   EXEC_NAME, VERSION, EXEC_NAME,
		   EXEC_NAME);
	ntfs_log_info("%s%s", ntfs_bugs, ntfs_home);
	exit(1);
}

/**
 * version
 */
__attribute__((noreturn))
static void version(void)
{
	ntfs_log_info("%s v%s\n\n"
		   "Attempt to fix an NTFS partition.\n\n"
		   "Copyright (c) 2000-2006 Anton Altaparmakov\n"
		   "Copyright (c) 2002-2006 Szabolcs Szakacsits\n"
		   "Copyright (c) 2007      Yura Pakhuchiy\n\n",
		   EXEC_NAME, VERSION);
	ntfs_log_info("%s\n%s%s", ntfs_gpl, ntfs_bugs, ntfs_home);
	exit(1);
}

/**
 * parse_options
 */
static void parse_options(int argc, char **argv)
{
	int c;
	static const char *sopt = "-hnV";
	static const struct option lopt[] = {
		{ "help",	no_argument,	NULL, 'h' },
		{ "no-action",	no_argument,	NULL, 'n' },
		{ "version",	no_argument,	NULL, 'V' },
		{ NULL, 0, NULL, 0 }
	};

	memset(&opt, 0, sizeof(opt));

	while ((c = getopt_long(argc, argv, sopt, lopt, NULL)) != -1) {
		switch (c) {
		case 1:	/* A non-option argument */
			if (!opt.volume)
				opt.volume = argv[optind - 1];
			else {
				ntfs_log_info("ERROR: Too many arguments.\n");
				usage();
			}
			break;
		case 'n':
			opt.no_action = TRUE;
			break;
		case 'h':
		case '?':
			usage();
			/* fall through */
		case 'V':
			version();
		default:
			ntfs_log_info("ERROR: Unknown option '%s'.\n", argv[optind - 1]);
			usage();
		}
	}

	if (opt.volume == NULL) {
		ntfs_log_info("ERROR: You must specify a device.\n");
		usage();
	}
}

/**
 * OLD_ntfs_volume_set_flags
 */
static int OLD_ntfs_volume_set_flags(ntfs_volume *vol, const le16 flags)
{
	MFT_RECORD *m = NULL;
	ATTR_RECORD *a;
	VOLUME_INFORMATION *c;
	ntfs_attr_search_ctx *ctx;
	int ret = -1;   /* failure */

	if (!vol) {
		errno = EINVAL;
		return -1;
	}
	if (ntfs_file_record_read(vol, FILE_Volume, &m, NULL)) {
		ntfs_log_perror("Failed to read $Volume");
		return -1;
	}
	/* Sanity check */
	if (!(m->flags & MFT_RECORD_IN_USE)) {
		ntfs_log_error("$Volume has been deleted. Cannot handle this "
				"yet. Run chkdsk to fix this.\n");
		errno = EIO;
		goto err_exit;
	}
	/* Get a pointer to the volume information attribute. */
	ctx = ntfs_attr_get_search_ctx(NULL, m);
	if (!ctx) {
		ntfs_log_debug("Failed to allocate attribute search "
				"context.\n");
		goto err_exit;
	}
	if (ntfs_attr_lookup(AT_VOLUME_INFORMATION, AT_UNNAMED, 0,
			CASE_SENSITIVE, 0, NULL, 0, ctx)) {
		ntfs_log_error("Attribute $VOLUME_INFORMATION was not found in "
				"$Volume!\n");
		goto err_out;
	}
	a = ctx->attr;
	/* Sanity check. */
	if (a->non_resident) {
		ntfs_log_error("Attribute $VOLUME_INFORMATION must be resident "
				"(and it isn't)!\n");
		errno = EIO;
		goto err_out;
	}
	/* Get a pointer to the value of the attribute. */
	c = (VOLUME_INFORMATION*)(le16_to_cpu(a->value_offset) + (char*)a);
	/* Sanity checks. */
	if ((char*)c + le32_to_cpu(a->value_length) >
			(char*)m + le32_to_cpu(m->bytes_in_use) ||
			le16_to_cpu(a->value_offset) +
			le32_to_cpu(a->value_length) > le32_to_cpu(a->length)) {
		ntfs_log_error("Attribute $VOLUME_INFORMATION in $Volume is "
				"corrupt!\n");
		errno = EIO;
		goto err_out;
	}
	/* Set the volume flags. */
	vol->flags = c->flags = flags;
	if (ntfs_mft_record_write(vol, FILE_Volume, m)) {
		ntfs_log_perror("Error writing $Volume");
		goto err_out;
	}
	ret = 0; /* success */
err_out:
	ntfs_attr_put_search_ctx(ctx);
err_exit:
	free(m);
	return ret;
}

/**
 * set_dirty_flag
 */
static int set_dirty_flag(ntfs_volume *vol)
{
	le16 flags;

	/* Porting note: We test for the current state of VOLUME_IS_DIRTY. This
	 * should actually be more appropriate than testing for NVolWasDirty. */
	if (vol->flags | VOLUME_IS_DIRTY)
		return 0;
	ntfs_log_info("Setting required flags on partition... ");
	/*
	 * Set chkdsk flag, i.e. mark the partition dirty so chkdsk will run
	 * and fix it for us.
	 */
	flags = vol->flags | VOLUME_IS_DIRTY;
	if (OLD_ntfs_volume_set_flags(vol, flags)) {
		ntfs_log_info(FAILED);
		ntfs_log_error("Error setting volume flags.\n");
		return -1;
	}
	vol->flags = flags;

	/* Porting note: libntfs-3g does not have the 'WasDirty' flag/property,
	 * and never touches the 'dirty' bit except when explicitly told to do
	 * so. Since we just wrote the VOLUME_IS_DIRTY bit to disk, and
	 * vol->flags is up-to-date, we can just ignore the NVolSetWasDirty
	 * statement. */
	/* NVolSetWasDirty(vol); */

	ntfs_log_info(OK);
	return 0;
}

/**
 * empty_journal
 */
static int empty_journal(ntfs_volume *vol)
{
	if (NVolLogFileEmpty(vol))
		return 0;
	ntfs_log_info("Going to empty the journal ($LogFile)... ");
	if (ntfs_logfile_reset(vol)) {
		ntfs_log_info(FAILED);
		ntfs_log_perror("Failed to reset $LogFile");
		return -1;
	}
	ntfs_log_info(OK);
	return 0;
}

/**
 * fix_mftmirr
 */
static int fix_mftmirr(ntfs_volume *vol)
{
	s64 l, br;
	unsigned char *m, *m2;
	int i, ret = -1; /* failure */
	BOOL done;

	ntfs_log_info("\nProcessing $MFT and $MFTMirr...\n");

	/* Load data from $MFT and $MFTMirr and compare the contents. */
	m = (u8*)malloc(vol->mftmirr_size << vol->mft_record_size_bits);
	if (!m) {
		ntfs_log_perror("Failed to allocate memory");
		return -1;
	}
	m2 = (u8*)malloc(vol->mftmirr_size << vol->mft_record_size_bits);
	if (!m2) {
		ntfs_log_perror("Failed to allocate memory");
		free(m);
		return -1;
	}

	ntfs_log_info("Reading $MFT... ");
	l = ntfs_attr_mst_pread(vol->mft_na, 0, vol->mftmirr_size,
			vol->mft_record_size, m);
	if (l != vol->mftmirr_size) {
		ntfs_log_info(FAILED);
		if (l != -1)
			errno = EIO;
		ntfs_log_perror("Failed to read $MFT");
		goto error_exit;
	}
	ntfs_log_info(OK);

	ntfs_log_info("Reading $MFTMirr... ");
	l = ntfs_attr_mst_pread(vol->mftmirr_na, 0, vol->mftmirr_size,
			vol->mft_record_size, m2);
	if (l != vol->mftmirr_size) {
		ntfs_log_info(FAILED);
		if (l != -1)
			errno = EIO;
		ntfs_log_perror("Failed to read $MFTMirr");
		goto error_exit;
	}
	ntfs_log_info(OK);

	/*
	 * FIXME: Need to actually check the $MFTMirr for being real. Otherwise
	 * we might corrupt the partition if someone is experimenting with
	 * software RAID and the $MFTMirr is not actually in the position we
	 * expect it to be... )-:
	 * FIXME: We should emit a warning it $MFTMirr is damaged and ask
	 * user whether to recreate it from $MFT or whether to abort. - The
	 * warning needs to include the danger of software RAID arrays.
	 * Maybe we should go as far as to detect whether we are running on a
	 * MD disk and if yes then bomb out right at the start of the program?
	 */

	ntfs_log_info("Comparing $MFTMirr to $MFT... ");
	done = FALSE;
	for (i = 0; i < vol->mftmirr_size; ++i) {
		MFT_RECORD *mrec, *mrec2;
		const char *ESTR[12] = { "$MFT", "$MFTMirr", "$LogFile",
			"$Volume", "$AttrDef", "root directory", "$Bitmap",
			"$Boot", "$BadClus", "$Secure", "$UpCase", "$Extend" };
		const char *s;
		BOOL use_mirr;

		if (i < 12)
			s = ESTR[i];
		else if (i < 16)
			s = "system file";
		else
			s = "mft record";

		use_mirr = FALSE;
		mrec = (MFT_RECORD*)(m + i * vol->mft_record_size);
		if (mrec->flags & MFT_RECORD_IN_USE) {
			if (ntfs_is_baad_record(mrec->magic)) {
				ntfs_log_info(FAILED);
				ntfs_log_error("$MFT error: Incomplete multi "
						"sector transfer detected in "
						"%s.\nCannot handle this yet. "
						")-:\n", s);
				goto error_exit;
			}
			if (!ntfs_is_mft_record(mrec->magic)) {
				ntfs_log_info(FAILED);
				ntfs_log_error("$MFT error: Invalid mft "
						"record for %s.\nCannot "
						"handle this yet. )-:\n", s);
				goto error_exit;
			}
		}
		mrec2 = (MFT_RECORD*)(m2 + i * vol->mft_record_size);
		if (mrec2->flags & MFT_RECORD_IN_USE) {
			if (ntfs_is_baad_record(mrec2->magic)) {
				ntfs_log_info(FAILED);
				ntfs_log_error("$MFTMirr error: Incomplete "
						"multi sector transfer "
						"detected in %s.\n", s);
				goto error_exit;
			}
			if (!ntfs_is_mft_record(mrec2->magic)) {
				ntfs_log_info(FAILED);
				ntfs_log_error("$MFTMirr error: Invalid mft "
						"record for %s.\n", s);
				goto error_exit;
			}
			/* $MFT is corrupt but $MFTMirr is ok, use $MFTMirr. */
			if (!(mrec->flags & MFT_RECORD_IN_USE) &&
					!ntfs_is_mft_record(mrec->magic))
				use_mirr = TRUE;
		}
		if (memcmp(mrec, mrec2, ntfs_mft_record_get_data_size(mrec))) {
			if (!done) {
				done = TRUE;
				ntfs_log_info(FAILED);
			}
			ntfs_log_info("Correcting differences in $MFT%s "
					"record %d...", use_mirr ? "" : "Mirr",
					i);
			br = ntfs_mft_record_write(vol, i,
					use_mirr ? mrec2 : mrec);
			if (br) {
				ntfs_log_info(FAILED);
				ntfs_log_perror("Error correcting $MFT%s",
						use_mirr ? "" : "Mirr");
				goto error_exit;
			}
			ntfs_log_info(OK);
		}
	}
	if (!done)
		ntfs_log_info(OK);
	ntfs_log_info("Processing of $MFT and $MFTMirr completed "
			"successfully.\n");
	ret = 0;
error_exit:
	free(m);
	free(m2);
	return ret;
}

/*
 *		Rewrite the $UpCase file as default
 *
 *	Returns 0 if could be written
 */

static int rewrite_upcase(ntfs_volume *vol, ntfs_attr *na)
{
	s64 l;
	int res;

		/* writing the $UpCase may require bitmap updates */
	res = -1;
	vol->lcnbmp_ni = ntfs_inode_open(vol, FILE_Bitmap);
	if (!vol->lcnbmp_ni) {
		ntfs_log_perror("Failed to open bitmap inode");
	} else {
		vol->lcnbmp_na = ntfs_attr_open(vol->lcnbmp_ni, AT_DATA,
					AT_UNNAMED, 0);
		if (!vol->lcnbmp_na) {
			ntfs_log_perror("Failed to open bitmap data attribute");
		} else {
			/* minimal consistency check on the bitmap */
			if (((vol->lcnbmp_na->data_size << 3)
				< vol->nr_clusters)
			    || ((vol->lcnbmp_na->data_size << 3)
				>= (vol->nr_clusters << 1))
			    || (vol->lcnbmp_na->data_size
					> vol->lcnbmp_na->allocated_size)) {
				ntfs_log_error("Corrupt cluster map size %lld"
					" (allocated %lld minimum %lld)\n",
					(long long)vol->lcnbmp_na->data_size, 
					(long long)vol->lcnbmp_na->allocated_size,
					(long long)(vol->nr_clusters + 7) >> 3);
			} else {
				ntfs_log_info("Rewriting $UpCase file\n");
				l = ntfs_attr_pwrite(na, 0, vol->upcase_len*2,
							vol->upcase);
				if (l != vol->upcase_len*2) {
					ntfs_log_error("Failed to rewrite $UpCase\n");
				} else {
					ntfs_log_info("$UpCase has been set to default\n");
					res = 0;
				}
			}
			ntfs_attr_close(vol->lcnbmp_na);
			vol->lcnbmp_na = (ntfs_attr*)NULL;
		}
		ntfs_inode_close(vol->lcnbmp_ni);
		vol->lcnbmp_ni = (ntfs_inode*)NULL;
	}
	return (res);
}

/*
 *		Fix the $UpCase file
 *
 *	Returns 0 if the table is valid or has been fixed
 */

static int fix_upcase(ntfs_volume *vol)
{
	ntfs_inode *ni;
	ntfs_attr *na;
	ntfschar *upcase;
	s64 l;
	u32 upcase_len;
	u32 k;
	int res;

	res = -1;
	ni = (ntfs_inode*)NULL;
	na = (ntfs_attr*)NULL;
	/* Now load the upcase table from $UpCase. */
	ntfs_log_debug("Loading $UpCase...\n");
	ni = ntfs_inode_open(vol, FILE_UpCase);
	if (!ni) {
		ntfs_log_perror("Failed to open inode FILE_UpCase");
		goto error_exit;
	}
	/* Get an ntfs attribute for $UpCase/$DATA. */
	na = ntfs_attr_open(ni, AT_DATA, AT_UNNAMED, 0);
	if (!na) {
		ntfs_log_perror("Failed to open ntfs attribute");
		goto error_exit;
	}
	/*
	 * Note: Normally, the upcase table has a length equal to 65536
	 * 2-byte Unicode characters but allow for different cases, so no
	 * checks done. Just check we don't overflow 32-bits worth of Unicode
	 * characters.
	 */
	if (na->data_size & ~0x1ffffffffULL) {
		ntfs_log_error("Error: Upcase table is too big (max 32-bit "
				"allowed).\n");
		errno = EINVAL;
		goto error_exit;
	}
	upcase_len = na->data_size >> 1;
	upcase = (ntfschar*)ntfs_malloc(na->data_size);
	if (!upcase)
		goto error_exit;
	/* Read in the $DATA attribute value into the buffer. */
	l = ntfs_attr_pread(na, 0, na->data_size, upcase);
	if (l != na->data_size) {
		ntfs_log_error("Failed to read $UpCase, unexpected length "
			       "(%lld != %lld).\n", (long long)l,
			       (long long)na->data_size);
		errno = EIO;
		goto error_exit;
	}
	/* Consistency check of $UpCase, restricted to plain ASCII chars */
	k = 0x20;
	while ((k < upcase_len)
	    && (k < 0x7f)
	    && (le16_to_cpu(upcase[k])
			== ((k < 'a') || (k > 'z') ? k : k + 'A' - 'a')))
		k++;
	if (k < 0x7f) {
		ntfs_log_error("Corrupted file $UpCase\n");
		if (!opt.no_action) {
			/* rewrite the $UpCase file from default */
			res = rewrite_upcase(vol, na);
			/* free the bad upcase record */
			if (!res)
				free(upcase);
		} else {
			/* keep the default upcase but return an error */
			free(upcase);
		}
	} else {
			/* accept the upcase table read from $UpCase */
		free(vol->upcase);
		vol->upcase = upcase;
		vol->upcase_len = upcase_len;
		res = 0;
	}
error_exit :
	/* Done with the $UpCase mft record. */
	if (na)
		ntfs_attr_close(na);
	if (ni && ntfs_inode_close(ni)) {
		ntfs_log_perror("Failed to close $UpCase");
	}
	return (res);
}

/*
 *		Rewrite the boot sector
 *
 *	Returns 0 if successful
 */

static int rewrite_boot(struct ntfs_device *dev, char *full_bs,
				s32 sector_size)
{
	s64 bw;
	int res;

	res = -1;
	ntfs_log_info("Rewriting the bootsector\n");
	bw = ntfs_pwrite(dev, 0, sector_size, full_bs);
	if (bw == sector_size)
		res = 0;
	else {
		if (bw != -1)
			errno = EINVAL;
		if (!bw)
			ntfs_log_error("Failed to rewrite the bootsector (size=0)\n");
		else
			ntfs_log_perror("Error rewriting the bootsector");
	}
	return (res);
}

/*
 *		Try an alternate boot sector and fix the real one
 *
 *	Only after successful checks is the boot sector rewritten.
 *
 *	The alternate boot sector is not rewritten, either because it
 *	was found correct, or because we truncated the file system
 *	and the last actual sector might be part of some file.
 *
 *	Returns 0 if successful
 */

static int try_fix_boot(ntfs_volume *vol, char *full_bs,
			s64 read_sector, s64 fix_sectors, s32 sector_size)
{
	s64 br;
	int res;
	s64 got_sectors;
	le16 sector_size_le;
	NTFS_BOOT_SECTOR *bs;

	res = -1;
	br = ntfs_pread(vol->dev, read_sector*sector_size,
					sector_size, full_bs);
	if (br != sector_size) {
		if (br != -1)
			errno = EINVAL;
		if (!br)
			ntfs_log_error("Failed to read alternate bootsector (size=0)\n");
		else
			ntfs_log_perror("Error reading alternate bootsector");
	} else {
		bs = (NTFS_BOOT_SECTOR*)full_bs;
		got_sectors = le64_to_cpu(bs->number_of_sectors);
		bs->number_of_sectors = cpu_to_le64(fix_sectors);
		/* alignment problem on Sparc, even doing memcpy() */
		sector_size_le = cpu_to_le16(sector_size);
		if (!memcmp(&sector_size_le, &bs->bpb.bytes_per_sector,2)
		    && ntfs_boot_sector_is_ntfs(bs)
		    && !ntfs_boot_sector_parse(vol, bs)) {
			ntfs_log_info("The alternate bootsector is usable\n");
			if (fix_sectors != got_sectors)
				ntfs_log_info("Set sector count to %lld instead of %lld\n",
						(long long)fix_sectors,
						(long long)got_sectors);
			/* fix the normal boot sector */
			if (!opt.no_action) {
				res = rewrite_boot(vol->dev, full_bs,
							sector_size);
			} else
				res = 0;
		}
		if (!res && !opt.no_action)
			ntfs_log_info("The boot sector has been rewritten\n");
	}
	return (res);
}

/*
 *		Try the alternate boot sector if the normal one is bad
 *
 *	Actually :
 *	- first try the last sector of the partition (expected location)
 *	- then try the last sector as shown in the main boot sector,
 *		(could be meaningful for an undersized partition)
 *	- finally try truncating the file system actual size of partition
 *		(could be meaningful for an oversized partition)
 *
 *	if successful, rewrite the normal boot sector accordingly
 *
 *	Returns 0 if successful
 */

static int try_alternate_boot(ntfs_volume *vol, char *full_bs,
			s32 sector_size, s64 shown_sectors)
{
	s64 actual_sectors;
	int res;

	res = -1;
	ntfs_log_info("Trying the alternate boot sector\n");

		/*
		 * We do not rely on the sector size defined in the
		 * boot sector, supposed to be corrupt, so we try to get
		 * the actual sector size and defaulting to 512 if failed
		 * to get. This value is only used to guess the alternate
		 * boot sector location and it is checked against the
		 * value found in the sector itself. It should not damage
		 * anything if wrong.
		 *
		 * Note : the real last sector is not accounted for here.
		 */
	actual_sectors = ntfs_device_size_get(vol->dev,sector_size) - 1;

		/* first try the actual last sector */
	if ((actual_sectors > 0)
	    && !try_fix_boot(vol, full_bs, actual_sectors,
				actual_sectors, sector_size))
		res = 0;

		/* then try the shown last sector, if less than actual */
	if (res
	    && (shown_sectors > 0)
	    && (shown_sectors < actual_sectors)
	    && !try_fix_boot(vol, full_bs, shown_sectors,
				shown_sectors, sector_size))
		res = 0;

		/* then try reducing the number of sectors to actual value */
	if (res
	    && (shown_sectors > actual_sectors)
	    && !try_fix_boot(vol, full_bs, 0, actual_sectors, sector_size))
		res = 0;

	return (res);
}

/*
 *		Try to fix problems which may arise in the start up sequence
 *
 *	This is a replay of the normal start up sequence with fixes when
 *	some problem arise.
 */

static int fix_startup(struct ntfs_device *dev, unsigned long flags)
{
	s64 br;
	ntfs_volume *vol;
	BOOL dev_open;
	s64 shown_sectors;
	char *full_bs;
	NTFS_BOOT_SECTOR *bs;
	s32 sector_size;
	int res;
	int eo;

	errno = 0;
	res = -1;
	dev_open = FALSE;
	if (!dev || !dev->d_ops || !dev->d_name) {
		errno = EINVAL;
		ntfs_log_perror("%s: dev = %p", __FUNCTION__, dev);
		goto error_exit;
	}

	/* Allocate the volume structure. */
	vol = ntfs_volume_alloc();
	if (!vol)
		goto error_exit;
	
	/* Create the default upcase table. */
	vol->upcase_len = ntfs_upcase_build_default(&vol->upcase);
	if (!vol->upcase_len || !vol->upcase)
		goto error_exit;

	/* Default with no locase table and case sensitive file names */
	vol->locase = (ntfschar*)NULL;
	NVolSetCaseSensitive(vol);
	
		/* by default, all files are shown and not marked hidden */
	NVolSetShowSysFiles(vol);
	NVolSetShowHidFiles(vol);
	NVolClearHideDotFiles(vol);
	if (flags & MS_RDONLY)
		NVolSetReadOnly(vol);
	
	/* ...->open needs bracketing to compile with glibc 2.7 */
	if ((dev->d_ops->open)(dev, NVolReadOnly(vol) ? O_RDONLY: O_RDWR)) {
		ntfs_log_perror("Error opening '%s'", dev->d_name);
		goto error_exit;
	}
	dev_open = TRUE;
	/* Attach the device to the volume. */
	vol->dev = dev;
	
	sector_size = ntfs_device_sector_size_get(dev);
	if (sector_size <= 0)
		sector_size = DEFAULT_SECTOR_SIZE;
	full_bs = (char*)malloc(sector_size);
	if (!full_bs)
		goto error_exit;
	/* Now read the bootsector. */
	br = ntfs_pread(dev, 0, sector_size, full_bs);
	if (br != sector_size) {
		if (br != -1)
			errno = EINVAL;
		if (!br)
			ntfs_log_error("Failed to read bootsector (size=0)\n");
		else
			ntfs_log_perror("Error reading bootsector");
		goto error_exit;
	}
	bs = (NTFS_BOOT_SECTOR*)full_bs;
	if (!ntfs_boot_sector_is_ntfs(bs)
		/* get the bootsector data, only fails when inconsistent */
	    || (ntfs_boot_sector_parse(vol, bs) < 0)) {
		shown_sectors = le64_to_cpu(bs->number_of_sectors);
		/* boot sector is wrong, try the alternate boot sector */
		if (try_alternate_boot(vol, full_bs, sector_size,
						shown_sectors)) {
			errno = EINVAL;
			goto error_exit;
		}
	}
	res = 0;
error_exit:
	if (res) {
		switch (errno) {
		case ENOMEM :
			ntfs_log_error("Failed to allocate memory\n");
			break;
		case EINVAL :
			ntfs_log_error("Unrecoverable error\n");
			break;
		default :
			break;
		}
	}
	eo = errno;
	free(bs);
	if (vol) {
		free(vol->upcase);
		free(vol);
	}
	if (dev_open) {
		(dev->d_ops->close)(dev);
	}
	errno = eo;
	return (res);
}

/**
 * fix_mount
 */
static int fix_mount(void)
{
	int ret = 0; /* default success */
	ntfs_volume *vol;
	struct ntfs_device *dev;
	unsigned long flags;

	ntfs_log_info("Attempting to correct errors... ");

	dev = ntfs_device_alloc(opt.volume, 0, &ntfs_device_default_io_ops,
			NULL);
	if (!dev) {
		ntfs_log_info(FAILED);
		ntfs_log_perror("Failed to allocate device");
		return -1;
	}
	flags = (opt.no_action ? MS_RDONLY : 0);
	vol = ntfs_volume_startup(dev, flags);
	if (!vol) {
		ntfs_log_info(FAILED);
		ntfs_log_perror("Failed to startup volume");

		/* Try fixing the bootsector and redo the startup */
		if (!fix_startup(dev, flags)) {
			if (opt.no_action)
				ntfs_log_info("The bootsector can be fixed, "
						"but no change was requested\n");
			else
				vol = ntfs_volume_startup(dev, flags);
		}
		if (!vol) {
			ntfs_log_error("Volume is corrupt. You should run chkdsk.\n");
			ntfs_device_free(dev);
			return -1;
		}
		if (opt.no_action)
			ret = -1; /* error present and not fixed */
	}
		/* if option -n proceed despite errors, to display them all */
	if ((!ret || opt.no_action) && (fix_mftmirr(vol) < 0))
		ret = -1;
	if ((!ret || opt.no_action) && (fix_upcase(vol) < 0))
		ret = -1;
	if ((!ret || opt.no_action) && (set_dirty_flag(vol) < 0))
		ret = -1;
	if ((!ret || opt.no_action) && (empty_journal(vol) < 0))
		ret = -1;
	/*
	 * ntfs_umount() will invoke ntfs_device_free() for us.
	 * Ignore the returned error resulting from partial mounting.
	 */
	ntfs_umount(vol, 1);
	return ret;
}

/**
 * main
 */
int main(int argc, char **argv)
{
	ntfs_volume *vol;
	unsigned long mnt_flags;
	unsigned long flags;
	int ret = 1; /* failure */
	BOOL force = FALSE;

	ntfs_log_set_handler(ntfs_log_handler_outerr);

	parse_options(argc, argv);

	if (!ntfs_check_if_mounted(opt.volume, &mnt_flags)) {
		if ((mnt_flags & NTFS_MF_MOUNTED) &&
				!(mnt_flags & NTFS_MF_READONLY) && !force) {
			ntfs_log_error("Refusing to operate on read-write "
					"mounted device %s.\n", opt.volume);
			exit(1);
		}
	} else
		ntfs_log_perror("Failed to determine whether %s is mounted",
				opt.volume);
	/* Attempt a full mount first. */
	flags = (opt.no_action ? MS_RDONLY : 0);
	ntfs_log_info("Mounting volume... ");
	vol = ntfs_mount(opt.volume, flags);
	if (vol) {
		ntfs_log_info(OK);
		ntfs_log_info("Processing of $MFT and $MFTMirr completed "
				"successfully.\n");
	} else {
		ntfs_log_info(FAILED);
		if (fix_mount() < 0) {
			if (opt.no_action)
				ntfs_log_info("No change made\n");
			exit(1);
		}
		vol = ntfs_mount(opt.volume, 0);
		if (!vol) {
			ntfs_log_perror("Remount failed");
			exit(1);
		}
	}
	/* So the unmount does not clear it again. */

	/* Porting note: The WasDirty flag was set here to prevent ntfs_unmount
	 * from clearing the dirty bit (which might have been set in
	 * fix_mount()). So the intention is to leave the dirty bit set.
	 *
	 * libntfs-3g does not automatically set or clear dirty flags on
	 * mount/unmount, this means that the assumption that the dirty flag is
	 * now set does not hold. So we need to set it if not already set. */
	if(!(vol->flags & VOLUME_IS_DIRTY) && ntfs_volume_write_flags(vol,
			vol->flags | VOLUME_IS_DIRTY)) {
		ntfs_log_error("Error: Failed to set volume dirty flag (%d "
			"(%s))!\n", errno, strerror(errno));
	}

	/* Check NTFS version is ok for us (in $Volume) */
	ntfs_log_info("NTFS volume version is %i.%i.\n", vol->major_ver,
			vol->minor_ver);
	if (ntfs_version_is_supported(vol)) {
		ntfs_log_error("Error: Unknown NTFS version.\n");
		goto error_exit;
	}
	if (vol->major_ver >= 3) {
		/*
		 * FIXME: If on NTFS 3.0+, check for presence of the usn
		 * journal and stamp it if present.
		 */
	}
	/* FIXME: We should be marking the quota out of date, too. */
	/* That's all for now! */
	ntfs_log_info("NTFS partition %s was processed successfully.\n",
			vol->dev->d_name);
	/* Set return code to 0. */
	ret = 0;
error_exit:
	if (ntfs_umount(vol, 0))
		ntfs_umount(vol, 1);
	if (ret)
		exit(ret);
	return ret;
}