Btrfs-progs: make printing subvol extensible to newer layouts

Currently you can print subvol in a list or table format.
This patch will provide a way to extend this to other formats
like the upcoming raw format.

Signed-off-by: Anand Jain <anand.jain@oracle.com>

3 files changed, 39 insertions, 14 deletions

diff --git a/btrfs-list.c b/btrfs-list.c
index a166c8b2..1ca7bc4e 100644
--- a/btrfs-list.c
+++ b/btrfs-list.c
@@ -54,12 +54,12 @@ struct {
 	{
 		.name		= "ID",
 		.column_name	= "ID",
-		.need_print	= 1,
+		.need_print	= 0,
 	},
 	{
 		.name		= "gen",
 		.column_name	= "Gen",
-		.need_print	= 1,
+		.need_print	= 0,
 	},
 	{
 		.name		= "cgen",
@@ -74,7 +74,7 @@ struct {
 	{
 		.name		= "top level",
 		.column_name	= "Top Level",
-		.need_print	= 1,
+		.need_print	= 0,
 	},
 	{
 		.name		= "otime",
@@ -94,7 +94,7 @@ struct {
 	{
 		.name		= "path",
 		.column_name	= "Path",
-		.need_print	= 1,
+		.need_print	= 0,
 	},
 	{
 		.name		= NULL,
@@ -1415,21 +1415,25 @@ static void print_all_volume_info_tab_head()
 }
 
 static void print_all_volume_info(struct root_lookup *sorted_tree,
-				  int is_tab_result)
+				  int layout)
 {
 	struct rb_node *n;
 	struct root_info *entry;
 
-	if (is_tab_result)
+	if (layout == BTRFS_LIST_LAYOUT_TABLE)
 		print_all_volume_info_tab_head();
 
 	n = rb_first(&sorted_tree->root);
 	while (n) {
 		entry = rb_entry(n, struct root_info, sort_node);
-		if (is_tab_result)
-			print_single_volume_info_table(entry);
-		else
+		switch (layout) {
+		case BTRFS_LIST_LAYOUT_DEFAULT:
 			print_single_volume_info_default(entry);
+			break;
+		case BTRFS_LIST_LAYOUT_TABLE:
+			print_single_volume_info_table(entry);
+			break;
+		}
 		n = rb_next(n);
 	}
 }
@@ -1455,7 +1459,7 @@ int btrfs_list_subvols(int fd, struct root_lookup *root_lookup)
 
 int btrfs_list_subvols_print(int fd, struct btrfs_list_filter_set *filter_set,
 		       struct btrfs_list_comparer_set *comp_set,
-		       int is_tab_result, int full_path)
+		       int layout, int full_path)
 {
 	struct root_lookup root_lookup;
 	struct root_lookup root_sort;
@@ -1468,7 +1472,7 @@ int btrfs_list_subvols_print(int fd, struct btrfs_list_filter_set *filter_set,
 	__filter_and_sort_subvol(&root_lookup, &root_sort, filter_set,
 				 comp_set, top_id);
 
-	print_all_volume_info(&root_sort, is_tab_result);
+	print_all_volume_info(&root_sort, layout);
 	__free_all_subvolumn(&root_lookup);
 
 	return 0;
diff --git a/btrfs-list.h b/btrfs-list.h
index 2870c718..e6268588 100644
--- a/btrfs-list.h
+++ b/btrfs-list.h
@@ -18,6 +18,9 @@
 
 #include "kerncompat.h"
 
+#define BTRFS_LIST_LAYOUT_DEFAULT	0
+#define BTRFS_LIST_LAYOUT_TABLE	1
+
 /*
  * one of these for each root we find.
  */
diff --git a/cmds-subvolume.c b/cmds-subvolume.c
index d46064af..596bd628 100644
--- a/cmds-subvolume.c
+++ b/cmds-subvolume.c
@@ -422,8 +422,19 @@ static int cmd_subvol_list(int argc, char **argv)
 					BTRFS_LIST_FILTER_TOPID_EQUAL,
 					top_id);
 
-	ret = btrfs_list_subvols_print(fd, filter_set, comparer_set,
-				is_tab_result,
+	/* by default we shall print the following columns*/
+	btrfs_list_setup_print_column(BTRFS_LIST_OBJECTID);
+	btrfs_list_setup_print_column(BTRFS_LIST_GENERATION);
+	btrfs_list_setup_print_column(BTRFS_LIST_TOP_LEVEL);
+	btrfs_list_setup_print_column(BTRFS_LIST_PATH);
+
+	if (is_tab_result)
+		ret = btrfs_list_subvols_print(fd, filter_set, comparer_set,
+				BTRFS_LIST_LAYOUT_TABLE,
+				!is_list_all && !is_only_in_path);
+	else
+		ret = btrfs_list_subvols_print(fd, filter_set, comparer_set,
+				BTRFS_LIST_LAYOUT_DEFAULT,
 				!is_list_all && !is_only_in_path);
 	if (ret)
 		return 19;
@@ -630,7 +641,14 @@ static int cmd_subvol_get_default(int argc, char **argv)
 	btrfs_list_setup_filter(&filter_set, BTRFS_LIST_FILTER_ROOTID,
 				default_id);
 
-	ret = btrfs_list_subvols_print(fd, filter_set, NULL, 0, 1);
+	/* by default we shall print the following columns*/
+	btrfs_list_setup_print_column(BTRFS_LIST_OBJECTID);
+	btrfs_list_setup_print_column(BTRFS_LIST_GENERATION);
+	btrfs_list_setup_print_column(BTRFS_LIST_TOP_LEVEL);
+	btrfs_list_setup_print_column(BTRFS_LIST_PATH);
+
+	ret = btrfs_list_subvols_print(fd, filter_set, NULL,
+		BTRFS_LIST_LAYOUT_DEFAULT, 1);
 	if (ret)
 		return 19;
 	return 0;