[PATCH 4/4] Btrfs-progs: list only snapshots of the given subvol

[Anand jain <Anand.Jain@oracle.com>]

From: Anand Jain <anand.jain@oracle.com>

btrfs su list -s /btrfs
ID 258 gen 6 cgen 6 top level 5 otime 2012-10-18 17:01:56 uuid f648cdda-4efa-6f45-bd6b-041a8ae1538e path ss1
ID 260 gen 8 cgen 8 top level 5 otime 2012-10-18 17:02:20 uuid ea8fdf85-8d3f-8946-b3af-ede510cdcf19 path ss2
ID 261 gen 9 cgen 9 top level 5 otime 2012-10-19 13:37:42 uuid 44560e56-3879-2146-8b24-e9048871892f path ss3

btrfs su list -s /btrfs/sv1
ID 258 gen 6 cgen 6 top level 5 otime 2012-10-18 17:01:56 uuid f648cdda-4efa-6f45-bd6b-041a8ae1538e path ss1
ID 261 gen 9 cgen 9 top level 5 otime 2012-10-19 13:37:42 uuid 44560e56-3879-2146-8b24-e9048871892f path ss3

btrfs su list -s /btrfs/sv2
ID 260 gen 8 cgen 8 top level 5 otime 2012-10-18 17:02:20 uuid ea8fdf85-8d3f-8946-b3af-ede510cdcf19 path ss2

Signed-off-by: Anand Jain <anand.jain@oracle.com>
---
 cmds-subvolume.c |   24 ++++++++++++++++++++++++
 1 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/cmds-subvolume.c b/cmds-subvolume.c
index f8beecc..c575720 100644
--- a/cmds-subvolume.c
+++ b/cmds-subvolume.c
@@ -307,6 +307,7 @@ static int cmd_subvol_list(int argc, char **argv)
 	int ret;
 	int c;
 	char *subvol, *mnt = NULL;
+	struct root_info ri;
 	int is_tab_result = 0;
 	int is_list_all = 0;
 	struct option long_options[] = {
@@ -314,6 +315,7 @@ static int cmd_subvol_list(int argc, char **argv)
 		{0, 0, 0, 0}
 	};
 
+	memset(&ri,'\0',sizeof(ri));
 	filter_set = btrfs_list_alloc_filter_set();
 	comparer_set = btrfs_list_alloc_comparer_set();
 
@@ -419,10 +421,32 @@ static int cmd_subvol_list(int argc, char **argv)
 					BTRFS_LIST_FILTER_TOPID_EQUAL,
 					top_id);
 
+	if (strcmp(subvol, mnt) != 0) {
+		if (btrfs_list_is_filter_set(filter_set, BTRFS_LIST_FILTER_SNAPSHOT_ONLY) >= 0) {
+			ri.full_path = subvol+strlen(mnt)+1;
+			if (btrfs_get_a_subvol(fd, &ri)) {
+				fprintf(stderr, "ERROR: can't find '%s'\n",
+					ri.full_path);
+				close(fd);
+				free(mnt);
+				return 13;
+			}
+			btrfs_list_setup_filter(&filter_set,
+				BTRFS_LIST_FILTER_BY_PARENT, (u64)&ri.uuid);
+		}
+	}
+
 	ret = btrfs_list_subvols(fd, filter_set, comparer_set,
 				is_tab_result);
 
 	free(mnt);
+	if (ri.path)
+		free(ri.path);
+	if (ri.name)
+		free(ri.name);
+	if (ri.full_path)
+		free(ri.full_path);
+
 	if (ret)
 		return 19;
 	return 0;
-- 
1.7.1