[parted-devel] [PATCH 2/4] do not discard bootcode from extended partition

[Joel Granados Moreno]

From: Petr Uzel <petr.uzel at suse.cz>

* libparted/labels/dos.c (write_ext_table): Do not discard
bootcode from extended partition on msdos label when some of
the logical partitions are changed.

Signed-off-by: Petr Uzel <petr.uzel at suse.cz>
---
 libparted/labels/dos.c |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/libparted/labels/dos.c b/libparted/labels/dos.c
index e2f4f0b..07d580f 100644
--- a/libparted/labels/dos.c
+++ b/libparted/labels/dos.c
@@ -1039,6 +1039,7 @@ write_ext_table (const PedDisk* disk,
 	DosRawTable		table;
 	PedPartition*		part;
 	PedSector		lba_offset;
+	void*			table_sector;
 
 	PED_ASSERT (disk != NULL, return 0);
 	PED_ASSERT (ped_disk_extended_partition (disk) != NULL, return 0);
@@ -1046,7 +1047,11 @@ write_ext_table (const PedDisk* disk,
 
 	lba_offset = ped_disk_extended_partition (disk)->geom.start;
 
-	memset (&table, 0, sizeof (DosRawTable));
+	if (ptt_read_sector (disk->dev, sector, &table_sector)) {
+		memcpy (&table, table_sector, sizeof(DosRawTable));
+		free(table_sector);
+	}
+	memset (&(table.partitions), 0, 4 * sizeof(DosRawPartition));
 	table.magic = PED_CPU_TO_LE16 (MSDOS_MAGIC);
 
 	if (!fill_raw_part (&table.partitions[0], logical, sector))
@@ -1077,10 +1082,15 @@ static int
 write_empty_table (const PedDisk* disk, PedSector sector)
 {
 	DosRawTable		table;
+	void*			table_sector;
 
 	PED_ASSERT (disk != NULL, return 0);
 
-	memset (&table, 0, sizeof (DosRawTable));
+	if (ptt_read_sector (disk->dev, sector, &table_sector)) {
+		memcpy (&table, table_sector, sizeof(DosRawTable));
+		free(table_sector);
+	}
+	memset (&(table.partitions), 0, 4 * sizeof(DosRawPartition));
 	table.magic = PED_CPU_TO_LE16 (MSDOS_MAGIC);
 
 	return ped_device_write (disk->dev, (void*) &table, sector, 1);
-- 
1.6.0.6