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Diffstat (limited to 'util-linux/volume_id/linux_swap.c')
-rw-r--r--util-linux/volume_id/linux_swap.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/util-linux/volume_id/linux_swap.c b/util-linux/volume_id/linux_swap.c
new file mode 100644
index 000000000..56b5d5085
--- /dev/null
+++ b/util-linux/volume_id/linux_swap.c
@@ -0,0 +1,73 @@
+/*
+ * volume_id - reads filesystem label and uuid
+ *
+ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "volume_id_internal.h"
+
+struct swap_header_v1_2 {
+ uint8_t bootbits[1024];
+ uint32_t version;
+ uint32_t last_page;
+ uint32_t nr_badpages;
+ uint8_t uuid[16];
+ uint8_t volume_name[16];
+} __attribute__((__packed__));
+
+#define LARGEST_PAGESIZE 0x4000
+
+int volume_id_probe_linux_swap(struct volume_id *id, uint64_t off)
+{
+ struct swap_header_v1_2 *sw;
+ const uint8_t *buf;
+ unsigned page;
+
+ dbg("probing at offset 0x%llx", (unsigned long long) off);
+
+ /* the swap signature is at the end of the PAGE_SIZE */
+ for (page = 0x1000; page <= LARGEST_PAGESIZE; page <<= 1) {
+ buf = volume_id_get_buffer(id, off + page-10, 10);
+ if (buf == NULL)
+ return -1;
+
+ if (memcmp(buf, "SWAP-SPACE", 10) == 0) {
+ id->type_version[0] = '1';
+ id->type_version[1] = '\0';
+ goto found;
+ }
+
+ if (memcmp(buf, "SWAPSPACE2", 10) == 0) {
+ sw = volume_id_get_buffer(id, off, sizeof(struct swap_header_v1_2));
+ if (sw == NULL)
+ return -1;
+ id->type_version[0] = '2';
+ id->type_version[1] = '\0';
+ volume_id_set_label_raw(id, sw->volume_name, 16);
+ volume_id_set_label_string(id, sw->volume_name, 16);
+ volume_id_set_uuid(id, sw->uuid, UUID_DCE);
+ goto found;
+ }
+ }
+ return -1;
+
+found:
+ volume_id_set_usage(id, VOLUME_ID_OTHER);
+ id->type = "swap";
+
+ return 0;
+}