Adding upstream version 3.6.upstream/3.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 876 insertions, 0 deletions

diff --git a/libparted/fs/r/fat/resize.c b/libparted/fs/r/fat/resize.c
new file mode 100644
index 0000000..78dede4
--- /dev/null
+++ b/libparted/fs/r/fat/resize.c
@@ -0,0 +1,876 @@
+/*
+    libparted
+    Copyright (C) 1998-2000, 2007-2014, 2019-2023 Free Software Foundation,
+    Inc.
+
+    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 3 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.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <config.h>
+#include "fat.h"
+#include "traverse.h"
+#include "count.h"
+#include "fatio.h"
+#include "calc.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <ctype.h>
+#include <stdarg.h>
+#include <string.h>
+
+#ifndef DISCOVER_ONLY
+
+/* Recursively builds (i.e. makes consistent) the duplicated directory tree
+ * (leaving the original directory tree in tact)
+ */
+static int
+fat_construct_directory (FatOpContext* ctx, FatTraverseInfo* trav_info)
+{
+	FatTraverseInfo*	sub_dir_info;
+	FatDirEntry*		dir_entry;
+	FatCluster		old_first_cluster;
+
+	while ( (dir_entry = fat_traverse_next_dir_entry (trav_info)) ) {
+		if (fat_dir_entry_is_null_term (dir_entry))
+			break;
+		if (!fat_dir_entry_has_first_cluster (dir_entry, ctx->old_fs))
+			continue;
+
+		fat_traverse_mark_dirty (trav_info);
+
+		old_first_cluster = fat_dir_entry_get_first_cluster (dir_entry,
+						ctx->old_fs);
+		fat_dir_entry_set_first_cluster (dir_entry, ctx->new_fs,
+			fat_op_context_map_cluster (ctx, old_first_cluster));
+
+		if (fat_dir_entry_is_directory (dir_entry)
+				&& dir_entry->name [0] != '.') {
+			sub_dir_info
+				= fat_traverse_directory (trav_info, dir_entry);
+			if (!sub_dir_info)
+				return 0;
+			if (!fat_construct_directory (ctx, sub_dir_info))
+				return 0;
+		}
+	}
+	/* remove "stale" entries at the end */
+	while ((dir_entry = fat_traverse_next_dir_entry (trav_info))) {
+		memset (dir_entry, 0, sizeof (FatDirEntry));
+		fat_traverse_mark_dirty (trav_info);
+	}
+	fat_traverse_complete (trav_info);
+	return 1;
+}
+
+static int
+duplicate_legacy_root_dir (FatOpContext* ctx)
+{
+	FatSpecific*		old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*		new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+
+	PED_ASSERT (old_fs_info->root_dir_sector_count
+			== new_fs_info->root_dir_sector_count);
+
+	if (!ped_geometry_read (ctx->old_fs->geom, old_fs_info->buffer,
+				old_fs_info->root_dir_offset,
+				old_fs_info->root_dir_sector_count))
+		return 0;
+
+	if (!ped_geometry_write (ctx->new_fs->geom, old_fs_info->buffer,
+				 new_fs_info->root_dir_offset,
+				 new_fs_info->root_dir_sector_count))
+		return 0;
+
+	return 1;
+}
+
+/*
+    Constructs the new directory tree for legacy (FAT16) file systems.
+*/
+static int
+fat_construct_legacy_root (FatOpContext* ctx)
+{
+	FatTraverseInfo*	trav_info;
+
+	if (!duplicate_legacy_root_dir (ctx))
+		return 0;
+	trav_info = fat_traverse_begin (ctx->new_fs, FAT_ROOT, "\\");
+	return fat_construct_directory (ctx, trav_info);
+}
+
+/*
+    Constructs the new directory tree for new (FAT32) file systems.
+*/
+static int
+fat_construct_root (FatOpContext* ctx)
+{
+	FatSpecific*		new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	FatTraverseInfo*	trav_info;
+
+	trav_info = fat_traverse_begin (ctx->new_fs, new_fs_info->root_cluster,
+					"\\");
+	fat_construct_directory (ctx, trav_info);
+	return 1;
+}
+
+/* Converts the root directory between FAT16 and FAT32.  NOTE: this code
+ * can also do no conversion.  I'm leaving fat_construct_directory(), because
+ * it's really pretty :-)  It also leaves a higher chance of deleted file
+ * recovery, because it doesn't remove redundant entries.  (We do this here,
+ * because brain-damaged FAT16 has an arbitary limit on root directory entries,
+ * so we save room)
+ */
+static int
+fat_convert_directory (FatOpContext* ctx, FatTraverseInfo* old_trav,
+		       FatTraverseInfo* new_trav)
+{
+	FatTraverseInfo*	sub_old_dir_trav;
+	FatTraverseInfo*	sub_new_dir_trav;
+	FatDirEntry*		new_dir_entry;
+	FatDirEntry*		old_dir_entry;
+	FatCluster		old_first_cluster;
+
+	while ( (old_dir_entry = fat_traverse_next_dir_entry (old_trav)) ) {
+		if (fat_dir_entry_is_null_term (old_dir_entry))
+			break;
+		if (!fat_dir_entry_is_active (old_dir_entry))
+			continue;
+
+		new_dir_entry = fat_traverse_next_dir_entry (new_trav);
+		if (!new_dir_entry) {
+			return ped_exception_throw (PED_EXCEPTION_ERROR,
+				PED_EXCEPTION_IGNORE_CANCEL,
+				_("There's not enough room in the root "
+				  "directory for all of the files.  Either "
+				  "cancel, or ignore to lose the files."))
+					== PED_EXCEPTION_IGNORE;
+		}
+
+		*new_dir_entry = *old_dir_entry;
+		fat_traverse_mark_dirty (new_trav);
+
+		if (!fat_dir_entry_has_first_cluster (old_dir_entry,
+						      ctx->old_fs))
+			continue;
+
+		old_first_cluster = fat_dir_entry_get_first_cluster (
+						old_dir_entry, ctx->old_fs);
+		fat_dir_entry_set_first_cluster (new_dir_entry, ctx->new_fs,
+			fat_op_context_map_cluster (ctx, old_first_cluster));
+
+		if (fat_dir_entry_is_directory (old_dir_entry)
+				&& old_dir_entry->name [0] != '.') {
+			sub_old_dir_trav
+			    = fat_traverse_directory (old_trav, old_dir_entry);
+			if (!sub_old_dir_trav) return 0;
+			sub_new_dir_trav
+			    = fat_traverse_directory (new_trav, new_dir_entry);
+			if (!sub_new_dir_trav) {
+				fat_traverse_complete (sub_old_dir_trav);
+				return 0;
+			}
+
+			if (!fat_convert_directory (ctx, sub_old_dir_trav,
+						    sub_new_dir_trav))
+				return 0;
+		}
+	}
+
+	/* remove "stale" entries at the end, just in case there is some
+	 * overlap
+	 */
+	while ((new_dir_entry = fat_traverse_next_dir_entry (new_trav))) {
+		memset (new_dir_entry, 0, sizeof (FatDirEntry));
+		fat_traverse_mark_dirty (new_trav);
+	}
+
+	fat_traverse_complete (old_trav);
+	fat_traverse_complete (new_trav);
+	return 1;
+}
+
+static void
+clear_cluster (PedFileSystem* fs, FatCluster cluster)
+{
+	FatSpecific*		fs_info = FAT_SPECIFIC (fs);
+
+	memset (fs_info->buffer, 0, fs_info->cluster_size);
+	fat_write_cluster (fs, fs_info->buffer, cluster);
+}
+
+/* This MUST be called BEFORE the fat_construct_new_fat(), because cluster
+ * allocation depend on the old FAT.  The reason is, old clusters may
+ * still be needed during the resize, (particularly clusters in the directory
+ * tree) even if they will be discarded later.
+ */
+static int
+alloc_root_dir (FatOpContext* ctx)
+{
+	FatSpecific*		old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*		new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	FatCluster		i;
+	FatCluster		cluster;
+	FatCluster		cluster_count;
+
+	PED_ASSERT (new_fs_info->fat_type == FAT_TYPE_FAT32);
+
+	cluster_count = ped_div_round_up (
+			   PED_MAX (16, old_fs_info->root_dir_sector_count),
+			   new_fs_info->cluster_sectors);
+
+	for (i = 0; i < cluster_count; i++) {
+		cluster = fat_table_alloc_check_cluster (new_fs_info->fat,
+							 ctx->new_fs);
+		if (!cluster)
+			return 0;
+		ctx->new_root_dir [i] = cluster;
+		clear_cluster (ctx->new_fs, cluster);
+	}
+	ctx->new_root_dir [i] = 0;
+	new_fs_info->root_cluster = ctx->new_root_dir [0];
+	return 1;
+}
+
+/* when converting FAT32 -> FAT16
+ * fat_duplicate clusters() duplicated the root directory unnecessarily.
+ * Let's free it.
+ *
+ * This must be called AFTER fat_construct_new_fat().  (otherwise, our
+ * changes just get overwritten)
+ */
+static int
+free_root_dir (FatOpContext* ctx)
+{
+	FatSpecific*		old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*		new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	FatCluster		old_cluster;
+	FatFragment		i;
+
+	PED_ASSERT (old_fs_info->fat_type == FAT_TYPE_FAT32);
+	PED_ASSERT (new_fs_info->fat_type == FAT_TYPE_FAT16);
+
+	for (old_cluster = old_fs_info->root_cluster;
+	     !fat_table_is_eof (old_fs_info->fat, old_cluster);
+	     old_cluster = fat_table_get (old_fs_info->fat, old_cluster)) {
+		FatFragment old_frag;
+		old_frag = fat_cluster_to_frag (ctx->old_fs, old_cluster);
+		for (i = 0; i < new_fs_info->cluster_frags; i++) {
+			FatFragment new_frag;
+			FatCluster new_clst;
+			new_frag = fat_op_context_map_fragment (ctx,
+								old_frag + i);
+			new_clst = fat_frag_to_cluster (ctx->old_fs, new_frag);
+			if (!fat_table_set_avail (new_fs_info->fat, new_clst))
+				return 0;
+		}
+	}
+
+	return 1;
+}
+
+static int
+fat_clear_root_dir (PedFileSystem* fs)
+{
+	FatSpecific*	fs_info = FAT_SPECIFIC (fs);
+	int		i;
+
+	PED_ASSERT (fs_info->fat_type == FAT_TYPE_FAT16);
+	PED_ASSERT (fs_info->root_dir_sector_count);
+
+	memset (fs_info->buffer, 0, 512);
+
+	for (i = 0; i < fs_info->root_dir_sector_count; i++) {
+		if (!ped_geometry_write (fs->geom, fs_info->buffer,
+					 fs_info->root_dir_offset + i, 1)) {
+			if (ped_exception_throw (PED_EXCEPTION_ERROR,
+				PED_EXCEPTION_IGNORE_CANCEL,
+				_("Error writing to the root directory."))
+					== PED_EXCEPTION_CANCEL)
+				return 0;
+		}
+	}
+	return 1;
+}
+
+static int
+fat_construct_converted_tree (FatOpContext* ctx)
+{
+	FatSpecific*		old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*		new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	FatTraverseInfo*	old_trav_info;
+	FatTraverseInfo*	new_trav_info;
+
+	if (new_fs_info->fat_type == FAT_TYPE_FAT32) {
+		new_trav_info = fat_traverse_begin (ctx->new_fs,
+					    new_fs_info->root_cluster, "\\");
+		if (!new_trav_info) return 0;
+		old_trav_info = fat_traverse_begin (ctx->old_fs, FAT_ROOT,
+						    "\\");
+	} else {
+		fat_clear_root_dir (ctx->new_fs);
+		new_trav_info = fat_traverse_begin (ctx->new_fs, FAT_ROOT,
+						    "\\");
+		if (!new_trav_info) return 0;
+		old_trav_info = fat_traverse_begin (ctx->old_fs,
+					    old_fs_info->root_cluster, "\\");
+	}
+	if (!old_trav_info) {
+		fat_traverse_complete (new_trav_info);
+		return 0;
+	}
+	if (!fat_convert_directory (ctx, old_trav_info, new_trav_info))
+		return 0;
+	return 1;
+}
+
+/*
+    Constructs the new directory tree to match the new file locations.
+*/
+static int
+fat_construct_dir_tree (FatOpContext* ctx)
+{
+	FatSpecific*		new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	FatSpecific*		old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+
+	if (new_fs_info->fat_type == old_fs_info->fat_type) {
+		switch (old_fs_info->fat_type) {
+                        case FAT_TYPE_FAT12:
+                        PED_ASSERT (0);
+                        break;
+
+			case FAT_TYPE_FAT16:
+			return fat_construct_legacy_root (ctx);
+
+			case FAT_TYPE_FAT32:
+			return fat_construct_root (ctx);
+		}
+	} else {
+		return fat_construct_converted_tree (ctx);
+	}
+
+	return 0;
+}
+
+static FatFragment
+_get_next_old_frag (FatOpContext* ctx, FatFragment frag)
+{
+	FatSpecific*	old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatCluster	cluster;
+	FatCluster	next_cluster;
+
+	if ((frag + 1) % old_fs_info->cluster_frags != 0) {
+		if (fat_is_fragment_active (ctx->old_fs, frag + 1))
+			return frag + 1;
+		else
+			return -1;
+	} else {
+		cluster = fat_frag_to_cluster (ctx->old_fs, frag);
+		next_cluster = fat_table_get (old_fs_info->fat, cluster);
+
+		if (fat_table_is_eof (old_fs_info->fat, next_cluster))
+			return -1;
+		else
+			return fat_cluster_to_frag (ctx->old_fs, next_cluster);
+	}
+}
+
+/*
+    Constructs the new fat for the resized file system.
+*/
+static int
+fat_construct_new_fat (FatOpContext* ctx)
+{
+	FatSpecific*	old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*	new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	FatFragment	old_frag;
+	FatCluster	new_cluster;
+	FatFragment	new_frag;
+	FatFragment	old_next_frag;
+	FatFragment	new_next_frag;
+	FatCluster	new_next_cluster;
+	FatClusterFlag	flag;
+	int		i;
+
+	fat_table_clear (new_fs_info->fat);
+	if (!fat_table_set_cluster_count (new_fs_info->fat,
+					  new_fs_info->cluster_count))
+		return 0;
+
+	for (old_frag = 0; old_frag < old_fs_info->frag_count; old_frag++) {
+		flag = fat_get_fragment_flag (ctx->old_fs, old_frag);
+		if (flag == FAT_FLAG_FREE)
+			continue;
+		if (flag == FAT_FLAG_BAD) {
+			new_frag = fat_op_context_map_static_fragment (
+						ctx, old_frag);
+			if (new_frag == -1)
+				continue;
+			new_cluster = fat_frag_to_cluster (ctx->new_fs,
+							   new_frag);
+			fat_table_set_bad (new_fs_info->fat, new_cluster);
+			continue;
+		}
+
+		new_frag = fat_op_context_map_fragment (ctx, old_frag);
+		new_cluster = fat_frag_to_cluster (ctx->new_fs, new_frag);
+
+		old_next_frag = _get_next_old_frag (ctx, old_frag);
+		if (old_next_frag == -1) {
+			fat_table_set_eof (new_fs_info->fat, new_cluster);
+			continue;
+		}
+
+		new_next_frag = fat_op_context_map_fragment (ctx,
+							     old_next_frag);
+		PED_ASSERT (new_next_frag != -1);
+
+		new_next_cluster = fat_frag_to_cluster (ctx->new_fs,
+							new_next_frag);
+		PED_ASSERT (new_next_cluster != new_cluster);
+
+		fat_table_set (new_fs_info->fat, new_cluster, new_next_cluster);
+	}
+
+	if (old_fs_info->fat_type == FAT_TYPE_FAT32
+	    && new_fs_info->fat_type == FAT_TYPE_FAT32) {
+		new_fs_info->root_cluster
+			= fat_op_context_map_cluster (ctx,
+					old_fs_info->root_cluster);
+	}
+
+	if (old_fs_info->fat_type == FAT_TYPE_FAT16
+	    && new_fs_info->fat_type == FAT_TYPE_FAT32) {
+		for (i=0; ctx->new_root_dir[i+1]; i++) {
+			fat_table_set (new_fs_info->fat,
+				       ctx->new_root_dir[i],
+				       ctx->new_root_dir[i+1]);
+		}
+		fat_table_set_eof (new_fs_info->fat, ctx->new_root_dir[i]);
+	}
+
+	return 1;
+}
+
+static int
+ask_type (PedFileSystem* fs, int fat16_ok, int fat32_ok, FatType* out_fat_type)
+{
+	FatSpecific*		fs_info = FAT_SPECIFIC (fs);
+	PedExceptionOption	status;
+	const char*		fat16_msg;
+	const char*		fat32_msg;
+
+	if (fs_info->fat_type == FAT_TYPE_FAT16)
+		fat16_msg = _("If you leave your file system as FAT16, "
+			      "then you will have no problems.");
+	else
+		fat16_msg = _("If you convert to FAT16, and MS Windows "
+			      "is installed on this partition, then "
+			      "you must re-install the MS Windows boot "
+			      "loader.  If you want to do this, you "
+			      "should consult the Parted manual (or "
+			      "your distribution's manual).");
+
+	if (fs_info->fat_type == FAT_TYPE_FAT32)
+		fat32_msg = _("If you leave your file system as FAT32, "
+			      "then you will not introduce any new "
+			      "problems.");
+	else
+		fat32_msg = _("If you convert to FAT32, and MS Windows "
+			      "is installed on this partition, then "
+			      "you must re-install the MS Windows boot "
+			      "loader.  If you want to do this, you "
+			      "should consult the Parted manual (or "
+			      "your distribution's manual).  Also, "
+			      "converting to FAT32 will make the file "
+			      "system unreadable by MS DOS, MS Windows "
+			      "95a, and MS Windows NT.");
+
+	if (fat16_ok && fat32_ok) {
+		status = ped_exception_throw (
+			 PED_EXCEPTION_INFORMATION,
+			 PED_EXCEPTION_YES_NO_CANCEL,
+			 _("%s  %s  %s"),
+			 _("Would you like to use FAT32?"),
+			 fat16_msg,
+			 fat32_msg);
+
+		switch (status) {
+		case PED_EXCEPTION_YES:
+			*out_fat_type = FAT_TYPE_FAT32;
+			return 1;
+
+		case PED_EXCEPTION_NO:
+			*out_fat_type = FAT_TYPE_FAT16;
+			return 1;
+
+		case PED_EXCEPTION_UNHANDLED:
+			*out_fat_type = fs_info->fat_type;
+			return 1;
+
+		case PED_EXCEPTION_CANCEL:
+			return 0;
+
+                default:
+                        PED_ASSERT (0);
+                        break;
+		}
+	}
+
+	if (fat16_ok) {
+		if (fs_info->fat_type != FAT_TYPE_FAT16) {
+			status = ped_exception_throw (
+				PED_EXCEPTION_WARNING,
+				PED_EXCEPTION_OK_CANCEL,
+				_("%s  %s"),
+				_("The file system can only be resized to this "
+				  "size by converting to FAT16."),
+				fat16_msg);
+			if (status == PED_EXCEPTION_CANCEL)
+				return 0;
+		}
+		*out_fat_type = FAT_TYPE_FAT16;
+		return 1;
+	}
+
+	if (fat32_ok) {
+		if (fs_info->fat_type != FAT_TYPE_FAT32) {
+			status = ped_exception_throw (
+				PED_EXCEPTION_WARNING,
+				PED_EXCEPTION_OK_CANCEL,
+				_("%s  %s"),
+				_("The file system can only be resized to this "
+				  "size by converting to FAT32."),
+				fat32_msg);
+			if (status == PED_EXCEPTION_CANCEL)
+				return 0;
+		}
+		*out_fat_type = FAT_TYPE_FAT32;
+		return 1;
+	}
+
+	ped_exception_throw (
+		PED_EXCEPTION_NO_FEATURE,
+		PED_EXCEPTION_CANCEL,
+		_("GNU Parted cannot resize this partition to this size.  "
+		  "We're working on it!"));
+
+	return 0;
+}
+
+/*  For resize operations: determine if the file system must be FAT16 or FAT32,
+ *  or either.  If the new file system must be FAT32, then query for
+ *  confirmation.  If either file system can be used, query for which one.
+ */
+static int
+get_fat_type (PedFileSystem* fs, const PedGeometry* new_geom,
+	      FatType* out_fat_type)
+{
+	FatSpecific*		fs_info = FAT_SPECIFIC (fs);
+	PedSector		fat16_cluster_sectors;
+	PedSector		fat32_cluster_sectors;
+	FatCluster		dummy_cluster_count;
+	PedSector		dummy_fat_sectors;
+	int			fat16_ok;
+	int			fat32_ok;
+
+	fat16_ok = fat_calc_resize_sizes (
+				    new_geom,
+				    fs_info->cluster_sectors,
+				    FAT_TYPE_FAT16,
+				    fs_info->root_dir_sector_count,
+				    fs_info->cluster_sectors,
+				    &fat16_cluster_sectors,
+				    &dummy_cluster_count,
+				    &dummy_fat_sectors);
+
+	fat32_ok = fat_calc_resize_sizes (
+				    new_geom,
+				    fs_info->cluster_sectors,
+				    FAT_TYPE_FAT32,
+				    fs_info->root_dir_sector_count,
+				    fs_info->cluster_sectors,
+				    &fat32_cluster_sectors,
+				    &dummy_cluster_count,
+				    &dummy_fat_sectors);
+
+	return ask_type (fs, fat16_ok, fat32_ok, out_fat_type);
+}
+
+/*  Creates the PedFileSystem struct for the new resized file system, and
+    sticks it in a FatOpContext.  At the end of the process, the original
+    (ctx->old_fs) is destroyed, and replaced with the new one (ctx->new_fs).
+ */
+static FatOpContext*
+create_resize_context (PedFileSystem* fs, const PedGeometry* new_geom)
+{
+	FatSpecific*	fs_info = FAT_SPECIFIC (fs);
+	FatSpecific*	new_fs_info;
+	PedFileSystem*	new_fs;
+	PedSector	new_cluster_sectors;
+	FatCluster	new_cluster_count;
+	PedSector	new_fat_sectors;
+	FatType		new_fat_type;
+	PedSector	root_dir_sector_count;
+	FatOpContext*	context;
+
+	/* hypothetical number of root dir sectors, if we end up using
+	 * FAT16
+	 */
+	if (fs_info->root_dir_sector_count)
+		root_dir_sector_count = fs_info->root_dir_sector_count;
+	else
+		root_dir_sector_count = FAT_ROOT_DIR_ENTRY_COUNT
+						* sizeof (FatDirEntry) / 512;
+
+	if (!get_fat_type (fs, new_geom, &new_fat_type))
+		return 0;
+
+	fat_calc_resize_sizes (new_geom, fs_info->cluster_sectors, new_fat_type,
+		root_dir_sector_count, fs_info->cluster_sectors,
+		&new_cluster_sectors, &new_cluster_count, &new_fat_sectors);
+
+	if (!fat_check_resize_geometry (fs, new_geom, new_cluster_sectors,
+				        new_cluster_count))
+		goto error;
+
+	new_fs = fat_alloc (new_geom);
+	if (!new_fs)
+		goto error;
+
+	new_fs_info = FAT_SPECIFIC (new_fs);
+	if (!new_fs_info)
+		goto error_free_new_fs;
+
+/* preserve boot code, etc. */
+	new_fs_info->boot_sector = ped_malloc (new_geom->dev->sector_size);
+	memcpy (new_fs_info->boot_sector, fs_info->boot_sector,
+		new_geom->dev->sector_size);
+	new_fs_info->info_sector = NULL;
+	if (fs_info->fat_type == FAT_TYPE_FAT32)
+	{
+		PED_ASSERT (fs_info->info_sector != NULL);
+		new_fs_info->info_sector =
+			ped_malloc (new_geom->dev->sector_size);
+		memcpy (new_fs_info->info_sector, fs_info->info_sector,
+			new_geom->dev->sector_size);
+	}
+
+	new_fs_info->logical_sector_size = fs_info->logical_sector_size;
+	new_fs_info->sector_count = new_geom->length;
+
+	new_fs_info->sectors_per_track = fs_info->sectors_per_track;
+	new_fs_info->heads = fs_info->heads;
+
+	new_fs_info->cluster_size = new_cluster_sectors * 512;
+	new_fs_info->cluster_sectors = new_cluster_sectors;
+	new_fs_info->cluster_count = new_cluster_count;
+	new_fs_info->dir_entries_per_cluster = fs_info->dir_entries_per_cluster;
+
+	new_fs_info->fat_type = new_fat_type;
+	new_fs_info->fat_table_count = 2;
+	new_fs_info->fat_sectors = new_fat_sectors;
+
+	/* what about copying? */
+	new_fs_info->serial_number = fs_info->serial_number;
+
+	if (new_fs_info->fat_type == FAT_TYPE_FAT32) {
+		new_fs_info->info_sector_offset	= 1;
+		new_fs_info->boot_sector_backup_offset = 6;
+
+		new_fs_info->root_dir_offset = 0;
+		new_fs_info->root_dir_entry_count = 0;
+		new_fs_info->root_dir_sector_count = 0;
+
+		/* we add calc_align_sectors to push the cluster_offset
+		   forward, to keep the clusters aligned between the new
+		   and old file systems
+		 */
+		new_fs_info->fat_offset
+			= fat_min_reserved_sector_count (FAT_TYPE_FAT32)
+			  + fat_calc_align_sectors (new_fs, fs);
+
+		new_fs_info->cluster_offset
+			= new_fs_info->fat_offset
+			  + 2 * new_fs_info->fat_sectors;
+	} else {
+		new_fs_info->root_dir_sector_count = root_dir_sector_count;
+		new_fs_info->root_dir_entry_count
+			= root_dir_sector_count * 512 / sizeof (FatDirEntry);
+
+		new_fs_info->fat_offset
+			= fat_min_reserved_sector_count (FAT_TYPE_FAT16)
+			  + fat_calc_align_sectors (new_fs, fs);
+
+		new_fs_info->root_dir_offset = new_fs_info->fat_offset
+					       + 2 * new_fs_info->fat_sectors;
+
+		new_fs_info->cluster_offset = new_fs_info->root_dir_offset
+					  + new_fs_info->root_dir_sector_count;
+	}
+
+	new_fs_info->total_dir_clusters = fs_info->total_dir_clusters;
+
+	context = fat_op_context_new (new_fs, fs);
+	if (!context)
+		goto error_free_new_fs_info;
+
+	if (!fat_op_context_create_initial_fat (context))
+		goto error_free_context;
+
+	if (!fat_alloc_buffers (new_fs))
+		goto error_free_fat;
+
+	return context;
+
+error_free_fat:
+	fat_table_destroy (new_fs_info->fat);
+error_free_context:
+	free (context);
+error_free_new_fs_info:
+	free (new_fs_info);
+error_free_new_fs:
+	free (new_fs);
+error:
+	return NULL;
+}
+
+static int
+resize_context_assimilate (FatOpContext* ctx)
+{
+	FatSpecific*	old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*	new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+
+	fat_free_buffers (ctx->old_fs);
+	fat_table_destroy (old_fs_info->fat);
+	free (old_fs_info);
+	ped_geometry_destroy (ctx->old_fs->geom);
+
+	ctx->old_fs->type_specific = ctx->new_fs->type_specific;
+	ctx->old_fs->geom = ctx->new_fs->geom;
+	ctx->old_fs->type = (new_fs_info->fat_type == FAT_TYPE_FAT16)
+				? &fat16_type
+			       	: &fat32_type;
+
+	free (ctx->new_fs);
+
+	fat_op_context_destroy (ctx);
+
+	return 1;
+}
+
+static int
+resize_context_abort (FatOpContext* ctx)
+{
+	FatSpecific*	new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+
+	fat_free_buffers (ctx->new_fs);
+	fat_table_destroy (new_fs_info->fat);
+	free (new_fs_info);
+	ped_geometry_destroy (ctx->new_fs->geom);
+	free (ctx->new_fs);
+
+	fat_op_context_destroy (ctx);
+
+	return 1;
+}
+
+/* copies the "hidden" sectors, between the boot sector and the FAT.  Required,
+ * for the Windows 98 FAT32 boot loader
+ */
+int
+_copy_hidden_sectors (FatOpContext* ctx)
+{
+	FatSpecific*    old_fs_info = FAT_SPECIFIC (ctx->old_fs);
+	FatSpecific*    new_fs_info = FAT_SPECIFIC (ctx->new_fs);
+	PedSector       first = 1;
+	PedSector       last;
+	PedSector       count;
+
+	/* nothing to copy for FAT16 */
+	if (old_fs_info->fat_type == FAT_TYPE_FAT16
+			|| new_fs_info->fat_type == FAT_TYPE_FAT16)
+		return 1;
+
+	last = PED_MIN (old_fs_info->fat_offset, new_fs_info->fat_offset) - 1;
+	count = last - first + 1;
+
+	PED_ASSERT (count < BUFFER_SIZE);
+
+	if (!ped_geometry_read (ctx->old_fs->geom, old_fs_info->buffer,
+				first, count))
+		return 0;
+	if (!ped_geometry_write (ctx->new_fs->geom, old_fs_info->buffer,
+				 first, count))
+		return 0;
+	return 1;
+}
+
+int
+fat_resize (PedFileSystem* fs, PedGeometry* geom, PedTimer* timer)
+{
+	FatSpecific*	fs_info = FAT_SPECIFIC (fs);
+	FatSpecific*	new_fs_info;
+	FatOpContext*	ctx;
+	PedFileSystem*	new_fs;
+
+	ctx = create_resize_context (fs, geom);
+	if (!ctx)
+		goto error;
+	new_fs = ctx->new_fs;
+	new_fs_info = FAT_SPECIFIC (new_fs);
+
+	if (!fat_duplicate_clusters (ctx, timer))
+		goto error_abort_ctx;
+	if (fs_info->fat_type == FAT_TYPE_FAT16
+			&& new_fs_info->fat_type == FAT_TYPE_FAT32) {
+		if (!alloc_root_dir (ctx))
+			goto error_abort_ctx;
+	}
+	if (!fat_construct_new_fat (ctx))
+		goto error_abort_ctx;
+	if (fs_info->fat_type == FAT_TYPE_FAT32
+			&& new_fs_info->fat_type == FAT_TYPE_FAT16) {
+		if (!free_root_dir (ctx))
+			goto error_abort_ctx;
+	}
+	if (!fat_construct_dir_tree (ctx))
+		goto error_abort_ctx;
+	if (!fat_table_write_all (new_fs_info->fat, new_fs))
+		goto error_abort_ctx;
+
+	_copy_hidden_sectors (ctx);
+	fat_boot_sector_generate (&new_fs_info->boot_sector, new_fs);
+	fat_boot_sector_write (new_fs_info->boot_sector, new_fs);
+	if (new_fs_info->fat_type == FAT_TYPE_FAT32) {
+		fat_info_sector_generate (&new_fs_info->info_sector, new_fs);
+		fat_info_sector_write (new_fs_info->info_sector, new_fs);
+	}
+
+	if (!resize_context_assimilate (ctx))
+		goto error;
+
+	return 1;
+
+error_abort_ctx:
+	resize_context_abort (ctx);
+error:
+	return 0;
+}
+
+#endif /* !DISCOVER_ONLY */