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-rw-r--r--libparted/filesys.c295
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diff --git a/libparted/filesys.c b/libparted/filesys.c
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+/*
+ libparted - a library for manipulating disk partitions
+ Copyright (C) 1999-2001, 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/>.
+*/
+
+/** \file filesys.c */
+
+/**
+ * \addtogroup PedFileSystem
+ *
+ * \note File systems exist on a PedGeometry - NOT a PedPartition.
+ *
+ * @{
+ */
+
+#include <config.h>
+
+#include <parted/parted.h>
+#include <parted/debug.h>
+
+#if ENABLE_NLS
+# include <libintl.h>
+# define _(String) dgettext (PACKAGE, String)
+#else
+# define _(String) (String)
+#endif /* ENABLE_NLS */
+
+#define BUFFER_SIZE 4096 /* in sectors */
+
+static PedFileSystemType* fs_types = NULL;
+static PedFileSystemAlias* fs_aliases = NULL;
+
+void
+ped_file_system_type_register (PedFileSystemType* fs_type)
+{
+ PED_ASSERT (fs_type != NULL);
+ PED_ASSERT (fs_type->ops != NULL);
+ PED_ASSERT (fs_type->name != NULL);
+
+ fs_type->next = fs_types;
+ fs_types = fs_type;
+}
+
+void
+ped_file_system_type_unregister (PedFileSystemType* fs_type)
+{
+ PedFileSystemType* walk;
+ PedFileSystemType* last = NULL;
+
+ PED_ASSERT (fs_types != NULL);
+ PED_ASSERT (fs_type != NULL);
+
+ for (walk = fs_types; walk && walk != fs_type;
+ last = walk, walk = walk->next);
+
+ PED_ASSERT (walk != NULL);
+ if (last)
+ ((struct _PedFileSystemType*) last)->next = fs_type->next;
+ else
+ fs_types = fs_type->next;
+}
+
+void
+ped_file_system_alias_register (PedFileSystemType* fs_type, const char* alias,
+ int deprecated)
+{
+ PedFileSystemAlias* fs_alias;
+
+ PED_ASSERT (fs_type != NULL);
+ PED_ASSERT (alias != NULL);
+
+ fs_alias = ped_malloc (sizeof *fs_alias);
+ if (!fs_alias)
+ return;
+
+ fs_alias->next = fs_aliases;
+ fs_alias->fs_type = fs_type;
+ fs_alias->alias = alias;
+ fs_alias->deprecated = deprecated;
+ fs_aliases = fs_alias;
+}
+
+void
+ped_file_system_alias_unregister (PedFileSystemType* fs_type,
+ const char* alias)
+{
+ PedFileSystemAlias* walk;
+ PedFileSystemAlias* last = NULL;
+
+ PED_ASSERT (fs_aliases != NULL);
+ PED_ASSERT (fs_type != NULL);
+ PED_ASSERT (alias != NULL);
+
+ for (walk = fs_aliases; walk; last = walk, walk = walk->next) {
+ if (walk->fs_type == fs_type && !strcmp (walk->alias, alias))
+ break;
+ }
+
+ PED_ASSERT (walk != NULL);
+ if (last)
+ last->next = walk->next;
+ else
+ fs_aliases = walk->next;
+ free (walk);
+}
+
+/**
+ * Get a PedFileSystemType by its @p name.
+ *
+ * @return @c NULL if none found.
+ */
+PedFileSystemType*
+ped_file_system_type_get (const char* name)
+{
+ PedFileSystemType* walk;
+ PedFileSystemAlias* alias_walk;
+
+ PED_ASSERT (name != NULL);
+
+ for (walk = fs_types; walk != NULL; walk = walk->next) {
+ if (!strcasecmp (walk->name, name))
+ break;
+ }
+ if (walk != NULL)
+ return walk;
+
+ for (alias_walk = fs_aliases; alias_walk != NULL;
+ alias_walk = alias_walk->next) {
+ if (!strcasecmp (alias_walk->alias, name))
+ break;
+ }
+ if (alias_walk != NULL) {
+ if (alias_walk->deprecated)
+ PED_DEBUG (0, "File system alias %s is deprecated",
+ name);
+ return alias_walk->fs_type;
+ }
+
+ return NULL;
+}
+
+/**
+ * Get the next PedFileSystemType after @p fs_type.
+ *
+ * @return @c NULL if @p fs_type is the last item in the list.
+ */
+PedFileSystemType*
+ped_file_system_type_get_next (const PedFileSystemType* fs_type)
+{
+ if (fs_type)
+ return fs_type->next;
+ else
+ return fs_types;
+}
+
+/**
+ * Get the next PedFileSystemAlias after @p fs_alias.
+ *
+ * @return @c NULL if @p fs_alias is the last item in the list.
+ */
+PedFileSystemAlias*
+ped_file_system_alias_get_next (const PedFileSystemAlias* fs_alias)
+{
+ if (fs_alias)
+ return fs_alias->next;
+ else
+ return fs_aliases;
+}
+
+/**
+ * Attempt to find a file system and return the region it occupies.
+ *
+ * @param fs_type The file system type to probe for.
+ * @param geom The region to be searched.
+ *
+ * @return @p NULL if @p fs_type file system wasn't detected
+ */
+PedGeometry*
+ped_file_system_probe_specific (
+ const PedFileSystemType* fs_type, PedGeometry* geom)
+{
+ PedGeometry* result;
+
+ PED_ASSERT (fs_type != NULL);
+ PED_ASSERT (fs_type->ops->probe != NULL);
+ PED_ASSERT (geom != NULL);
+
+ if (!ped_device_open (geom->dev))
+ return 0;
+ result = fs_type->ops->probe (geom);
+ ped_device_close (geom->dev);
+ return result;
+}
+
+static int
+_geometry_error (const PedGeometry* a, const PedGeometry* b)
+{
+ PedSector start_delta = a->start - b->start;
+ PedSector end_delta = a->end - b->end;
+
+ return llabs (start_delta) + llabs (end_delta);
+}
+
+static PedFileSystemType*
+_best_match (const PedGeometry* geom, PedFileSystemType* detected [],
+ const int detected_error [], int detected_count)
+{
+ int best_match = 0;
+ int i;
+ PedSector min_error;
+
+ min_error = PED_MAX (4096, geom->length / 100);
+
+ for (i = 1; i < detected_count; i++) {
+ if (detected_error [i] < detected_error [best_match])
+ best_match = i;
+ }
+
+ /* make sure the best match is significantly better than all the
+ * other matches
+ */
+ for (i = 0; i < detected_count; i++) {
+ if (i == best_match)
+ continue;
+
+ if (abs (detected_error [best_match] - detected_error [i])
+ < min_error)
+ return NULL;
+ }
+
+ return detected [best_match];
+}
+
+
+/**
+ * Attempt to detect a file system in region \p geom.
+ * This function tries to be clever at dealing with ambiguous
+ * situations, such as when one file system was not completely erased before a
+ * new file system was created on top of it.
+ *
+ * \return a new PedFileSystem on success, \c NULL on failure
+ */
+PedFileSystemType*
+ped_file_system_probe (PedGeometry* geom)
+{
+ PedFileSystemType* detected[32];
+ int detected_error[32];
+ int detected_count = 0;
+ PedFileSystemType* walk = NULL;
+
+ PED_ASSERT (geom != NULL);
+
+ if (!ped_device_open (geom->dev))
+ return NULL;
+
+ ped_exception_fetch_all ();
+ while ( (walk = ped_file_system_type_get_next (walk)) ) {
+ PedGeometry* probed;
+
+ probed = ped_file_system_probe_specific (walk, geom);
+ if (probed) {
+ detected [detected_count] = walk;
+ detected_error [detected_count]
+ = _geometry_error (geom, probed);
+ detected_count++;
+ ped_geometry_destroy (probed);
+ } else {
+ ped_exception_catch ();
+ }
+ }
+ ped_exception_leave_all ();
+
+ ped_device_close (geom->dev);
+
+ if (!detected_count)
+ return NULL;
+ walk = _best_match (geom, detected, detected_error, detected_count);
+ if (walk)
+ return walk;
+ return NULL;
+}