/*
 * unix.c - The unix-specific code for e2fsck
 * 
 * Copyright (C) 1993, 1994, 1995, 1996, 1997 Theodore Ts'o.
 *
 * %Begin-Header%
 * This file may be redistributed under the terms of the GNU Public
 * License.
 * %End-Header%
 */

#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <string.h>
#include <fcntl.h>
#include <ctype.h>
#include <termios.h>
#include <time.h>
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif
#include <unistd.h>
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_MNTENT_H
#include <mntent.h>
#endif
#include <sys/ioctl.h>
#include <malloc.h>

#include "et/com_err.h"
#include "e2fsck.h"
#include "problem.h"
#include "../version.h"

extern int isatty(int);

/* Command line options */
static int blocksize = 0;
static int swapfs = 0;
static int normalize_swapfs = 0;
static int cflag = 0;		/* check disk */
static int show_version_only = 0;
static int force = 0;
static int verbose = 0;

static int replace_bad_blocks = 0;
static char *bad_blocks_file = 0;

static int possible_block_sizes[] = { 1024, 2048, 4096, 8192, 0};

static int root_filesystem = 0;
static int read_only_root = 0;

int restart_e2fsck = 0;

static void usage(e2fsck_t ctx)
{
	fprintf(stderr,
		"Usage: %s [-panyrcdfvstFSV] [-b superblock] [-B blocksize]\n"
		"\t\t[-I inode_buffer_blocks] [-P process_inode_size]\n"
		"\t\t[-l|-L bad_blocks_file] device\n", ctx->program_name);
	exit(FSCK_USAGE);
}

static void show_stats(e2fsck_t	ctx)
{
	ext2_filsys fs = ctx->fs;
	int inodes, inodes_used, blocks, blocks_used;
	int dir_links;
	int num_files, num_links;
	int frag_percent;

	dir_links = 2 * ctx->fs_directory_count - 1;
	num_files = ctx->fs_total_count - dir_links;
	num_links = ctx->fs_links_count - dir_links;
	inodes = fs->super->s_inodes_count;
	inodes_used = (fs->super->s_inodes_count -
		       fs->super->s_free_inodes_count);
	blocks = fs->super->s_blocks_count;
	blocks_used = (fs->super->s_blocks_count -
		       fs->super->s_free_blocks_count);

	frag_percent = (10000 * ctx->fs_fragmented) / inodes_used;
	frag_percent = (frag_percent + 5) / 10;
	
	if (!verbose) {
		printf("%s: %d/%d files (%0d.%d%% non-contiguous), %d/%d blocks\n",
		       ctx->device_name, inodes_used, inodes,
		       frag_percent / 10, frag_percent % 10,
		       blocks_used, blocks);
		return;
	}
	printf ("\n%8d inode%s used (%d%%)\n", inodes_used,
		(inodes_used != 1) ? "s" : "",
		100 * inodes_used / inodes);
	printf ("%8d non-contiguous inodes (%0d.%d%%)\n",
		ctx->fs_fragmented, frag_percent / 10, frag_percent % 10);
	printf ("         # of inodes with ind/dind/tind blocks: %d/%d/%d\n",
		ctx->fs_ind_count, ctx->fs_dind_count, ctx->fs_tind_count);
	printf ("%8d block%s used (%d%%)\n"
		"%8d bad block%s\n", blocks_used,
		(blocks_used != 1) ? "s" : "",
		100 * blocks_used / blocks, ctx->fs_badblocks_count,
		ctx->fs_badblocks_count != 1 ? "s" : "");
	printf ("\n%8d regular file%s\n"
		"%8d director%s\n"
		"%8d character device file%s\n"
		"%8d block device file%s\n"
		"%8d fifo%s\n"
		"%8d link%s\n"
		"%8d symbolic link%s (%d fast symbolic link%s)\n"
		"%8d socket%s\n"
		"--------\n"
		"%8d file%s\n",
		ctx->fs_regular_count,
		(ctx->fs_regular_count != 1) ? "s" : "",
		ctx->fs_directory_count,
		(ctx->fs_directory_count != 1) ? "ies" : "y",
		ctx->fs_chardev_count,
		(ctx->fs_chardev_count != 1) ? "s" : "",
		ctx->fs_blockdev_count,
		(ctx->fs_blockdev_count != 1) ? "s" : "",
		ctx->fs_fifo_count,
		(ctx->fs_fifo_count != 1) ? "s" : "",
		ctx->fs_links_count - dir_links,
		((ctx->fs_links_count - dir_links) != 1) ? "s" : "",
		ctx->fs_symlinks_count,
		(ctx->fs_symlinks_count != 1) ? "s" : "",
		ctx->fs_fast_symlinks_count,
		(ctx->fs_fast_symlinks_count != 1) ? "s" : "",
		ctx->fs_sockets_count, (ctx->fs_sockets_count != 1) ? "s" : "",
		ctx->fs_total_count - dir_links,
		((ctx->fs_total_count - dir_links) != 1) ? "s" : "");
}

static void check_mount(e2fsck_t ctx)
{
	errcode_t	retval;
	int		mount_flags, cont, fd;

	retval = ext2fs_check_if_mounted(ctx->filesystem_name, &mount_flags);
	if (retval) {
		com_err("ext2fs_check_if_mount", retval,
			"while determining whether %s is mounted.",
			ctx->filesystem_name);
		return;
	}
	if (!(mount_flags & EXT2_MF_MOUNTED))
		return;

#if (defined(__linux__) && defined(HAVE_MNTENT_H))
	/*
	 * If the root is mounted read-only, then /etc/mtab is
	 * probably not correct; so we won't issue a warning based on
	 * it.
	 */
	fd = open(MOUNTED, O_RDWR);
	if (fd < 0) {
		if (errno == EROFS)
			return;
	} else
		close(fd);
#endif
	
	if (ctx->options & E2F_OPT_READONLY) {
		printf("Warning!  %s is mounted.\n", ctx->device_name);
		return;
	}

	printf("%s is mounted.\n\n", ctx->device_name);
	printf("\a\a\a\aWARNING!!!  Running e2fsck on a mounted filesystem "
	       "may cause\nSEVERE filesystem damage.\a\a\a\n\n");
	if (isatty (0) && isatty (1))
		cont = ask_yn("Do you really want to continue", -1);
	else
		cont = 0;
	if (!cont) {
		printf ("check aborted.\n");
		exit (0);
	}
	return;
}

static void sync_disks(NOARGS)
{
	sync();
	sync();
	sleep(1);
	sync();
}

/*
 * This routine checks to see if a filesystem can be skipped; if so,
 * it will exit with E2FSCK_OK.  Under some conditions it will print a
 * message explaining why a check is being forced.
 */
static void check_if_skip(e2fsck_t ctx)
{
	ext2_filsys fs = ctx->fs;
	const char *reason = NULL;
	
	if (force || bad_blocks_file || cflag || swapfs)
		return;
	
	if (fs->super->s_state & EXT2_ERROR_FS)
		reason = "contains a file system with errors";
	else if (fs->super->s_mnt_count >=
		 (unsigned) fs->super->s_max_mnt_count)
		reason = "has reached maximal mount count";
	else if (fs->super->s_checkinterval &&
		 time(0) >= (fs->super->s_lastcheck +
			     fs->super->s_checkinterval))
		reason = "has gone too long without being checked";
	else if ((fs->super->s_state & EXT2_VALID_FS) == 0)
		reason = "was not cleanly unmounted";
	if (reason) {
		printf("%s %s, check forced.\n", ctx->device_name, reason);
		return;
	}
	printf("%s: clean, %d/%d files, %d/%d blocks\n", ctx->device_name,
	       fs->super->s_inodes_count - fs->super->s_free_inodes_count,
	       fs->super->s_inodes_count,
	       fs->super->s_blocks_count - fs->super->s_free_blocks_count,
	       fs->super->s_blocks_count);
	ext2fs_close(fs);
	exit(FSCK_OK);
}


#define PATH_SET "PATH=/sbin"

static errcode_t PRS(int argc, char *argv[], e2fsck_t *ret_ctx)
{
	int		flush = 0;
	int		c;
#ifdef MTRACE
	extern void	*mallwatch;
#endif
	char		*oldpath = getenv("PATH");
	e2fsck_t	ctx;
	errcode_t	retval;

	retval = e2fsck_allocate_context(&ctx);
	if (retval)
		return retval;

	*ret_ctx = ctx;

	/* Update our PATH to include /sbin  */
	if (oldpath) {
		char *newpath;

		newpath = malloc(sizeof (PATH_SET) + 1 + strlen (oldpath));
		if (!newpath)
			fatal_error("Couldn't malloc() newpath");
		strcpy (newpath, PATH_SET);
		strcat (newpath, ":");
		strcat (newpath, oldpath);
		putenv (newpath);
	} else
		putenv (PATH_SET);

	setbuf(stdout, NULL);
	setbuf(stderr, NULL);
	initialize_ext2_error_table();
	
	if (argc && *argv)
		ctx->program_name = *argv;
	else
		ctx->program_name = "e2fsck";
	while ((c = getopt (argc, argv, "panyrcB:dfvtFVM:b:I:P:l:L:N:Ss")) != EOF)
		switch (c) {
		case 'p':
		case 'a':
			ctx->options |= E2F_OPT_PREEN;
			ctx->options &= ~(E2F_OPT_YES|E2F_OPT_NO);
			break;
		case 'n':
			ctx->options |= E2F_OPT_NO;
			ctx->options &= ~(E2F_OPT_YES|E2F_OPT_PREEN);
			break;
		case 'y':
			ctx->options |= E2F_OPT_YES;
			ctx->options &= ~(E2F_OPT_PREEN|E2F_OPT_NO);
			break;
		case 't':
#ifdef RESOURCE_TRACK
			if (ctx->options & E2F_OPT_TIME)
				ctx->options |= E2F_OPT_TIME2;
			else
				ctx->options |= E2F_OPT_TIME;
#else
			fprintf(stderr, "The -t option is not "
				"supported on this version of e2fsck.\n");
#endif
			break;
		case 'c':
			cflag++;
			ctx->options |= E2F_OPT_CHECKBLOCKS;
			break;
		case 'r':
			/* What we do by default, anyway! */
			break;
		case 'b':
			ctx->use_superblock = atoi(optarg);
			break;
		case 'B':
			blocksize = atoi(optarg);
			break;
		case 'I':
			ctx->inode_buffer_blocks = atoi(optarg);
			break;
		case 'P':
			ctx->process_inode_size = atoi(optarg);
			break;
		case 'L':
			replace_bad_blocks++;
		case 'l':
			bad_blocks_file = malloc(strlen(optarg)+1);
			if (!bad_blocks_file)
				fatal_error("Couldn't malloc bad_blocks_file");
			strcpy(bad_blocks_file, optarg);
			break;
		case 'd':
			ctx->options |= E2F_OPT_DEBUG;
			break;
		case 'f':
			force = 1;
			break;
		case 'F':
#ifdef BLKFLSBUF
			flush = 1;
#else
			fatal_error ("-F not supported");
#endif
			break;
		case 'v':
			verbose = 1;
			break;
		case 'V':
			show_version_only = 1;
			break;
#ifdef MTRACE
		case 'M':
			mallwatch = (void *) strtol(optarg, NULL, 0);
			break;
#endif
		case 'N':
			ctx->device_name = optarg;
			break;
		case 's':
			normalize_swapfs = 1;
		case 'S':
			swapfs = 1;
			break;
		default:
			usage(ctx);
		}
	if (show_version_only)
		return 0;
	if (optind != argc - 1)
		usage(ctx);
	if ((ctx->options & E2F_OPT_NO) && !bad_blocks_file &&
	    !cflag && !swapfs)
		ctx->options |= E2F_OPT_READONLY;
	ctx->filesystem_name = argv[optind];
	if (ctx->device_name == 0)
		ctx->device_name = ctx->filesystem_name;
	if (flush) {
#ifdef BLKFLSBUF
		int	fd = open(ctx->filesystem_name, O_RDONLY, 0);

		if (fd < 0) {
			com_err("open", errno, "while opening %s for flushing",
				ctx->filesystem_name);
			exit(FSCK_ERROR);
		}
		if (ioctl(fd, BLKFLSBUF, 0) < 0) {
			com_err("BLKFLSBUF", errno, "while trying to flush %s",
				ctx->filesystem_name);
			exit(FSCK_ERROR);
		}
		close(fd);
#else
		fatal_error ("BLKFLSBUF not supported");
#endif /* BLKFLSBUF */
	}
	if (swapfs) {
		if (cflag || bad_blocks_file) {
			fprintf(stderr, "Incompatible options not "
				"allowed when byte-swapping.\n");
			fatal_error(0);
		}
	}
	return 0;
}

static const char *my_ver_string = E2FSPROGS_VERSION;
static const char *my_ver_date = E2FSPROGS_DATE;
					
int main (int argc, char *argv[])
{
	errcode_t	retval = 0;
	int		exit_value = FSCK_OK;
	int		i;
	ext2_filsys	fs = 0;
	io_manager	io_ptr;
	struct ext2fs_sb *s;
	const char	*lib_ver_date;
	int		my_ver, lib_ver;
	e2fsck_t	ctx;
	struct problem_context pctx;
	int flags;
	
	clear_problem_context(&pctx);
#ifdef MTRACE
	mtrace();
#endif
#ifdef MCHECK
	mcheck(0);
#endif
	my_ver = ext2fs_parse_version_string(my_ver_string);
	lib_ver = ext2fs_get_library_version(0, &lib_ver_date);
	if (my_ver > lib_ver) {
		fprintf( stderr, "Error: ext2fs library version "
			"out of date!\n");
		show_version_only++;
	}
	
	retval = PRS(argc, argv, &ctx);
	if (retval) {
		com_err("e2fsck", retval,
			"while trying to initialize program");
		exit(1);
	}

#ifdef RESOURCE_TRACK
	init_resource_track(&ctx->global_rtrack);
#endif

	if (!(ctx->options & E2F_OPT_PREEN) || show_version_only)
		fprintf (stderr, "e2fsck %s, %s for EXT2 FS %s, %s\n",
			 my_ver_string, my_ver_date, EXT2FS_VERSION,
			 EXT2FS_DATE);

	if (show_version_only) {
		fprintf(stderr, "\tUsing %s, %s\n",
			error_message(EXT2_ET_BASE), lib_ver_date);
		exit(0);
	}
	
	check_mount(ctx);
	
	if (!(ctx->options & E2F_OPT_PREEN) &&
	    !(ctx->options & E2F_OPT_NO) &&
	    !(ctx->options & E2F_OPT_YES)) {
		if (!isatty (0) || !isatty (1))
			die ("need terminal for interactive repairs");
	}
	ctx->superblock = ctx->use_superblock;
restart:
#if 1
	io_ptr = unix_io_manager;
#else
	io_ptr = test_io_manager;
	test_io_backing_manager = unix_io_manager;
#endif
	sync_disks();
	flags = (ctx->options & E2F_OPT_READONLY) ? 0 : EXT2_FLAG_RW;
	if (ctx->superblock && blocksize) {
		retval = ext2fs_open(ctx->filesystem_name, flags,
				     ctx->superblock, blocksize, io_ptr, &fs);
	} else if (ctx->superblock) {
		for (i=0; possible_block_sizes[i]; i++) {
			retval = ext2fs_open(ctx->filesystem_name, flags,
					     ctx->superblock,
					     possible_block_sizes[i],
					     io_ptr, &fs);
			if (!retval)
				break;
		}
	} else 
		retval = ext2fs_open(ctx->filesystem_name, flags, 
				     0, 0, io_ptr, &fs);
	if (!ctx->superblock && !(ctx->options & E2F_OPT_PREEN) && 
	    ((retval == EXT2_ET_BAD_MAGIC) ||
	     ((retval == 0) && ext2fs_check_desc(fs)))) {
		if (!fs || (fs->group_desc_count > 1)) {
			printf("%s trying backup blocks...\n",
			       retval ? "Couldn't find ext2 superblock," :
			       "Group descriptors look bad...");
			ctx->superblock = get_backup_sb(fs);
			if (fs)
				ext2fs_close(fs);
			goto restart;
		}
	}
	if (retval) {
		com_err(ctx->program_name, retval, "while trying to open %s",
			ctx->filesystem_name);
		if (retval == EXT2_ET_REV_TOO_HIGH)
			printf ("Get a newer version of e2fsck!\n");
		else if (retval == EXT2_ET_SHORT_READ)
			printf ("Could this be a zero-length partition?\n");
		else if ((retval == EPERM) || (retval == EACCES))
			printf("You must have %s access to the "
			       "filesystem or be root\n",
			       (ctx->options & E2F_OPT_READONLY) ?
			       "r/o" : "r/w");
		else if (retval == ENXIO)
			printf("Possibly non-existent or swap device?\n");
		else
			fix_problem(ctx, PR_0_SB_CORRUPT, &pctx);
		fatal_error(0);
	}
	ctx->fs = fs;
	fs->private = ctx;
#ifdef	EXT2_CURRENT_REV
	if (fs->super->s_rev_level > E2FSCK_CURRENT_REV) {
		com_err(ctx->program_name, EXT2_ET_REV_TOO_HIGH,
			"while trying to open %s",
			ctx->filesystem_name);
		goto get_newer;
	}
#endif
	/*
	 * Check for compatibility with the feature sets.  We need to
	 * be more stringent than ext2fs_open().
	 */
	s = (struct ext2fs_sb *) fs->super;
	if ((s->s_feature_compat & ~EXT2_LIB_FEATURE_COMPAT_SUPP) ||
	    (s->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP)) {
		com_err(ctx->program_name, EXT2_ET_UNSUPP_FEATURE,
			"(%s)", ctx->filesystem_name);
	get_newer:
		printf ("Get a newer version of e2fsck!\n");
		fatal_error(0);
	}
	if (s->s_feature_ro_compat & ~EXT2_LIB_FEATURE_RO_COMPAT_SUPP) {
		com_err(ctx->program_name, EXT2_ET_RO_UNSUPP_FEATURE,
			"(%s)", ctx->filesystem_name);
		goto get_newer;
	}
	
	/*
	 * If the user specified a specific superblock, presumably the
	 * master superblock has been trashed.  So we mark the
	 * superblock as dirty, so it can be written out.
	 */
	if (ctx->superblock &&
	    !(ctx->options & E2F_OPT_READONLY))
		ext2fs_mark_super_dirty(fs);

	/*
	 * Don't overwrite the backup superblock and block
	 * descriptors, until we're sure the filesystem is OK....
	 */
	fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;

	ehandler_init(fs->io);

	if (ctx->superblock)
		set_latch_flags(PR_LATCH_RELOC, PRL_LATCHED, 0);
	check_super_block(ctx);
	check_if_skip(ctx);
	if (bad_blocks_file)
		read_bad_blocks_file(ctx, bad_blocks_file, replace_bad_blocks);
	else if (cflag)
		test_disk(ctx);

	if (normalize_swapfs) {
		if ((fs->flags & EXT2_FLAG_SWAP_BYTES) ==
		    ext2fs_native_flag()) {
			fprintf(stderr, "%s: Filesystem byte order "
				"already normalized.\n", ctx->device_name);
			fatal_error(0);
		}
	}
	if (swapfs)
		swap_filesys(ctx);

	/*
	 * Mark the system as valid, 'til proven otherwise
	 */
	ext2fs_mark_valid(fs);

	retval = ext2fs_read_bb_inode(fs, &fs->badblocks);
	if (retval) {
		com_err(ctx->program_name, retval,
			"while reading bad blocks inode");
		preenhalt(ctx);
		printf("This doesn't bode well, but we'll try to go on...\n");
	}
	
	pass1(ctx);
	if (restart_e2fsck) {
		ext2fs_close(fs);
		printf("Restarting e2fsck from the beginning...\n");
		restart_e2fsck = 0;
		retval = e2fsck_reset_context(ctx);
		if (retval) {
			com_err(ctx->program_name, retval,
				"while resetting context");
			exit(1);
		}
		goto restart;
	}
	pass2(ctx);
	pass3(ctx);
	pass4(ctx);
	pass5(ctx);

#ifdef MTRACE
	mtrace_print("Cleanup");
#endif
	if (ext2fs_test_changed(fs)) {
		exit_value = FSCK_NONDESTRUCT;
		if (!(ctx->options & E2F_OPT_PREEN))
			printf("\n%s: ***** FILE SYSTEM WAS MODIFIED *****\n",
			       ctx->device_name);
		if (root_filesystem && !read_only_root) {
			printf("%s: ***** REBOOT LINUX *****\n",
			       ctx->device_name);
			exit_value = FSCK_REBOOT;
		}
	}
	if (ext2fs_test_valid(fs))
		fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
	else
		exit_value = FSCK_UNCORRECTED;
	if (!(ctx->options & E2F_OPT_READONLY)) {
		if (ext2fs_test_valid(fs)) {
			if (!(fs->super->s_state & EXT2_VALID_FS))
				exit_value = FSCK_NONDESTRUCT;
			fs->super->s_state = EXT2_VALID_FS;
		} else
			fs->super->s_state &= ~EXT2_VALID_FS;
		fs->super->s_mnt_count = 0;
		fs->super->s_lastcheck = time(NULL);
		ext2fs_mark_super_dirty(fs);
	}
	show_stats(ctx);

	write_bitmaps(ctx);
	ext2fs_close(fs);
	sync_disks();
	
#ifdef RESOURCE_TRACK
	if (ctx->options & E2F_OPT_TIME)
		print_resource_track(NULL, &ctx->global_rtrack);
#endif

	e2fsck_free_context(ctx);
	
	return exit_value;
}