[Ocfs2-tools-devel] [PATCH 6/7] mkfs.ocfs2: Add dry-run option

[Sunil Mushran]

Add a dry-run option to see the various values selected by mkfs.

Signed-off-by: Sunil Mushran <sunil.mushran at oracle.com>
---
 mkfs.ocfs2/mkfs.c          |   20 ++++++++++++++++----
 mkfs.ocfs2/mkfs.h          |    1 +
 mkfs.ocfs2/mkfs.ocfs2.8.in |    4 ++++
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/mkfs.ocfs2/mkfs.c b/mkfs.ocfs2/mkfs.c
index ca88a68..ef01277 100644
--- a/mkfs.ocfs2/mkfs.c
+++ b/mkfs.ocfs2/mkfs.c
@@ -128,6 +128,7 @@ enum {
 	FEATURES_OPTION,
 	CLUSTER_STACK_OPTION,
 	CLUSTER_NAME_OPTION,
+	DRY_RUN_OPTION,
 };
 
 static uint64_t align_bytes_to_clusters_ceil(State *s,
@@ -510,15 +511,20 @@ main(int argc, char **argv)
 
 	fill_defaults(s);
 
-	clear_both_ends(s);
-
 	generate_uuid (s);
 
 	create_generation(s);
 
 	print_state (s);
 
-	check_32bit_blocks (s);
+	check_32bit_blocks(s);
+
+	if (s->dry_run) {
+		close_device(s);
+		return 0;
+	}
+
+	clear_both_ends(s);
 
 	init_record(s, &superblock_rec, SFI_OTHER, S_IFREG | 0644);
 	init_record(s, &root_dir_rec, SFI_OTHER, S_IFDIR | 0755);
@@ -769,7 +775,7 @@ get_state(int argc, char **argv)
 	State *s;
 	int c;
 	int verbose = 0, quiet = 0, force = 0, xtool = 0, hb_dev = 0;
-	int show_version = 0;
+	int show_version = 0, dry_run = 0;
 	char *device_name;
 	int ret;
 	uint64_t val;
@@ -798,6 +804,7 @@ get_state(int argc, char **argv)
 		{ "fs-features=", 1, 0, FEATURES_OPTION },
 		{ "cluster-stack=", 1, 0, CLUSTER_STACK_OPTION },
 		{ "cluster-name=", 1, 0, CLUSTER_NAME_OPTION },
+		{ "dry-run", 0, 0, DRY_RUN_OPTION },
 		{ 0, 0, 0, 0}
 	};
 
@@ -985,6 +992,10 @@ get_state(int argc, char **argv)
 			cluster_name = strdup(optarg);
 			break;
 
+		case DRY_RUN_OPTION:
+			dry_run = 1;
+			break;
+
 		default:
 			usage(progname);
 			break;
@@ -1027,6 +1038,7 @@ get_state(int argc, char **argv)
 	s->verbose       = verbose;
 	s->quiet         = quiet;
 	s->force         = force;
+	s->dry_run       = dry_run;
 
 	s->prompt        = xtool ? 0 : 1;
 
diff --git a/mkfs.ocfs2/mkfs.h b/mkfs.ocfs2/mkfs.h
index 9b50a9f..b702f00 100644
--- a/mkfs.ocfs2/mkfs.h
+++ b/mkfs.ocfs2/mkfs.h
@@ -188,6 +188,7 @@ struct _State {
 	int mount;
 	int no_backup_super;
 	int inline_data;
+	int dry_run;
 
 	uint32_t blocksize;
 	uint32_t blocksize_bits;
diff --git a/mkfs.ocfs2/mkfs.ocfs2.8.in b/mkfs.ocfs2/mkfs.ocfs2.8.in
index e436550..0043b0d 100644
--- a/mkfs.ocfs2/mkfs.ocfs2.8.in
+++ b/mkfs.ocfs2/mkfs.ocfs2.8.in
@@ -200,6 +200,10 @@ Choose the maximum amount of features available. This will typically provide the
 This option is deprecated, please use \fB--fs-features=nobackup-super\fR instead.
 
 .TP
+\fB--dry-run\fR
+Display the heuristically determined values without overwriting the existing file system.
+
+.TP
 \fB\-q, \-\-quiet\fR
 Quiet mode.
 
-- 
1.6.3.3