libblkid: improve FreeBSD partitions parsing

FreeBSD since version 10 uses relative offsets for nested partitions.
Based on Richard Narron changes in kernel:block/partitions/msdos.c.

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

diff --git a/libblkid/src/partitions/bsd.c b/libblkid/src/partitions/bsd.c
index d83f2cf024764ddb28eb4d77e6b536014200015c..c74517334f0d5535fd9602f25876ee6036e1d1a8 100644 (file)
--- a/libblkid/src/partitions/bsd.c
+++ b/libblkid/src/partitions/bsd.c
@@ -37,6 +37,7 @@ static int probe_bsd_pt(blkid_probe pr, const struct blkid_idmag *mag)
        int i, nparts = BSD_MAXPARTITIONS;
        unsigned char *data;
        int rc = BLKID_PROBE_NONE;
+       uint32_t abs_offset = 0;
 
        if (blkid_partitions_need_typeonly(pr))
                /* caller does not ask for details about partitions */
@@ -62,6 +63,7 @@ static int probe_bsd_pt(blkid_probe pr, const struct blkid_idmag *mag)
                switch(blkid_partition_get_type(parent)) {
                case MBR_FREEBSD_PARTITION:
                        name = "freebsd";
+                       abs_offset = blkid_partition_get_start(parent);
                        break;
                case MBR_NETBSD_PARTITION:
                        name = "netbsd";
@@ -96,13 +98,20 @@ static int probe_bsd_pt(blkid_probe pr, const struct blkid_idmag *mag)
                blkid_partition par;
                uint32_t start, size;
 
-               /* TODO: in fdisk-mode returns all non-zero (p_size) partitions */
                if (p->p_fstype == BSD_FS_UNUSED)
                        continue;
 
                start = le32_to_cpu(p->p_offset);
                size = le32_to_cpu(p->p_size);
 
+               /* FreeBSD since version 10 uses relative offsets. We can use
+                * 3rd partition (special wholedisk partition) to detect this
+                * situation.
+                */
+               if (abs_offset && nparts >= 3
+                   && le32_to_cpu(l->d_partitions[2].p_offset) == 0)
+                       start += abs_offset;
+
                if (parent && blkid_partition_get_start(parent) == start
                           && blkid_partition_get_size(parent) == size) {
                        DBG(LOWPROBE, ul_debug(