*
* Copyright (C) 2005-2007 Kay Sievers <kay.sievers@vrfy.org>
*
- * 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 version 2 of the License.
+ * 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. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE 1
#endif
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
-
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "libvolume_id.h"
#include "libvolume_id-private.h"
-#include "util.h"
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
{ volume_id_probe_squashfs, { "squashfs", } },
{ volume_id_probe_netware, { "netware", } },
{ volume_id_probe_oracleasm, { "oracleasm", } },
+ { volume_id_probe_btrfs, { "btrfs", } },
};
/* the user can overwrite this log function */
if (!device_is_readable(id, off))
return -1;
- info("probing at offset 0x%llx, size 0x%llx\n",
- (unsigned long long) off, (unsigned long long) size);
+ info("probing at offset 0x%" PRIx64 ", size 0x%" PRIx64 "\n", off, size);
- for (i = 0; i < ARRAY_SIZE(prober_raid); i++)
- if (prober_raid[i].prober(id, off, size) == 0)
+ for (i = 0; i < ARRAY_SIZE(prober_raid); i++) {
+ if (prober_raid[i].prober(id, off, size) == 0) {
+ info("signature '%s' detected\n", id->type);
goto found;
+ }
+ }
return -1;
found:
return 0;
}
+static void volume_id_reset_result(struct volume_id *id)
+{
+ id->label_raw_len = 0;
+ id->label[0] = '\0';
+ id->uuid_raw_len = 0;
+ id->uuid[0] = '\0';
+ id->usage_id = VOLUME_ID_UNUSED;
+ id->usage = NULL;
+ id->type = NULL;
+ id->type_version[0] = '\0';
+}
+
/**
* volume_id_probe_filesystem:
* @id: Probing context.
if (!device_is_readable(id, off))
return -1;
- info("probing at offset 0x%llx, size 0x%llx\n",
- (unsigned long long) off, (unsigned long long) size);
+ info("probing at offset 0x%" PRIx64 ", size 0x%" PRIx64 "\n", off, size);
+
+ /*
+ * We probe for all known filesystems to find conflicting signatures. If
+ * we find multiple matching signatures and one of the detected filesystem
+ * types claims that it can not co-exist with any other filesystem type,
+ * we do not return a probing result.
+ *
+ * We can not afford to mount a volume with the wrong filesystem code and
+ * possibly corrupt it. Linux sytems have the problem of dozens of possible
+ * filesystem types, and volumes with left-over signatures from former
+ * filesystem types. Invalid signatures need to be removed from the volume
+ * to make the filesystem detection successful.
+ *
+ * We do not want to read that many bytes from probed floppies, skip volumes
+ * smaller than a usual floppy disk.
+ */
+ if (size > 1440 * 1024) {
+ int found = 0;
+ int force_unique_result = 0;
+ int first_match = -1;
+
+ volume_id_reset_result(id);
+ for (i = 0; i < ARRAY_SIZE(prober_filesystem); i++) {
+ int match;
+
+ match = (prober_filesystem[i].prober(id, off, size) == 0);
+ if (match) {
+ info("signature '%s' %i detected\n", id->type, i);
+ if (id->force_unique_result)
+ force_unique_result = 1;
+ if (found && force_unique_result) {
+ info("conflicting signatures found, skip results\n");
+ return -1;
+ }
+ found++;
+ if (first_match < 0)
+ first_match = i;
+ }
+ }
+ if (found < 1)
+ return -1;
+ if (found == 1)
+ goto found;
+ if (found > 1) {
+ volume_id_reset_result(id);
+ info("re-read first match metadata %i\n", first_match);
+ if (prober_filesystem[first_match].prober(id, off, size) == 0)
+ goto found;
+ return -1;
+ }
+ }
- for (i = 0; i < ARRAY_SIZE(prober_filesystem); i++)
- if (prober_filesystem[i].prober(id, off, size) == 0)
+ /* return the first match */
+ volume_id_reset_result(id);
+ for (i = 0; i < ARRAY_SIZE(prober_filesystem); i++) {
+ if (prober_filesystem[i].prober(id, off, size) == 0) {
+ info("signature '%s' detected\n", id->type);
goto found;
+ }
+ }
return -1;
-
found:
/* If recognized, we free the allocated buffers */
volume_id_free_buffer(id);
{
struct volume_id *id;
- id = malloc(sizeof(struct volume_id));
+ id = calloc(1, sizeof(struct volume_id));
if (id == NULL)
return NULL;
- memset(id, 0x00, sizeof(struct volume_id));
id->fd = fd;
if (id == NULL)
return;
- if (id->fd_close != 0)
- close(id->fd);
-
volume_id_free_buffer(id);
free(id);
~ianmdlvl / elogind.git / blobdiff