From: Karel Zak <kzak@redhat.com>
Date: Thu, 13 Jun 2013 13:11:04 +0000 (+0200)
Subject: libblkid: support pseudo PARTUUID= for MBR
X-Git-Tag: v2.24-rc1~494
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d67cc2889a0527b26d7bb8c76f2acac46751d673;p=thirdparty%2Futil-linux.git

libblkid: support pseudo PARTUUID= for MBR

  # blkid /dev/sdb1
  dev/sdb1: TYPE="ext2" PARTUUID="54e743a7-01"

the PARTUUID is generated from MBR Id and partition number. The same
method uses Linux kernel for root=PARTUUID= on systems with MBR.

Note that the patch also removes 0x prefix from PTUUID.

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/libblkid/src/partitions/dos.c b/libblkid/src/partitions/dos.c
index a9c79c34ad..a8c6276a7f 100644
--- a/libblkid/src/partitions/dos.c
+++ b/libblkid/src/partitions/dos.c
@@ -103,6 +103,7 @@ static int parse_dos_extended(blkid_probe pr, blkid_parttable tab,
 
 			blkid_partition_set_type(par, p->sys_type);
 			blkid_partition_set_flags(par, p->boot_ind);
+			blkid_partition_gen_uuid(par);
 			ct_nodata = 0;
 		}
 		/* The first nested ext.partition should be a link to the next
@@ -185,7 +186,7 @@ static int probe_dos_pt(blkid_probe pr,
 
 	id = dos_parttable_id(data);
 	if (id)
-		snprintf(idstr, sizeof(idstr), "0x%08x", id);
+		snprintf(idstr, sizeof(idstr), "%08x", id);
 
 	/*
 	 * Well, all checks pass, it's MS-DOS partiton table
@@ -232,6 +233,7 @@ static int probe_dos_pt(blkid_probe pr,
 
 		blkid_partition_set_type(par, p->sys_type);
 		blkid_partition_set_flags(par, p->boot_ind);
+		blkid_partition_gen_uuid(par);
 	}
 
 	/* Linux uses partition numbers greater than 4
diff --git a/libblkid/src/partitions/partitions.c b/libblkid/src/partitions/partitions.c
index 46631032af..22373f8a91 100644
--- a/libblkid/src/partitions/partitions.c
+++ b/libblkid/src/partitions/partitions.c
@@ -1281,6 +1281,16 @@ int blkid_partition_set_uuid(blkid_partition par, const unsigned char *uuid)
 	return 0;
 }
 
+int blkid_partition_gen_uuid(blkid_partition par)
+{
+	if (!par || !par->tab || !*par->tab->id)
+		return -1;
+
+	snprintf(par->uuid, sizeof(par->uuid), "%s-%02x",
+			par->tab->id, par->partno);
+	return 0;
+}
+
 /**
  * blkid_partition_get_name:
  * @par: partition
diff --git a/libblkid/src/partitions/partitions.h b/libblkid/src/partitions/partitions.h
index 44423d9ccf..f7d1ba3d14 100644
--- a/libblkid/src/partitions/partitions.h
+++ b/libblkid/src/partitions/partitions.h
@@ -40,6 +40,7 @@ extern int blkid_partition_set_utf8name(blkid_partition par,
 
 extern int blkid_partition_set_uuid(blkid_partition par,
 		const unsigned char *uuid);
+extern int blkid_partition_gen_uuid(blkid_partition par);
 
 extern int blkid_partition_set_type(blkid_partition par, int type);