Add "flags" metadata field (akin to "status") for backward-compatible flags.

The "status" field is treated as it ever has been, unknown flags there are
treated as fatal metadata errors. However, in the "flags" field, any unknown
flags will be ignored and silently dropped. This improves
backward-compatibility possibilities. (Any versions without support for this
new "flag" field will drop the field altogether, which is same as ignoring all
the flags there.)

1 files changed, 17 insertions, 6 deletions

diff --git a/lib/format_text/export.c b/lib/format_text/export.c
index 9c138d4a..b6e818fe 100644
--- a/lib/format_text/export.c
+++ b/lib/format_text/export.c
@@ -321,6 +321,20 @@ static int _print_header(struct formatter *f,
 	return 1;
 }
 
+static int _print_flag_config(struct formatter *f, int status, int type)
+{
+	char buffer[4096];
+	if (!print_flags(status, type | STATUS_FLAG, buffer, sizeof(buffer)))
+		return_0;
+	outf(f, "status = %s", buffer);
+
+	if (!print_flags(status, type, buffer, sizeof(buffer)))
+		return_0;
+	outf(f, "flags = %s", buffer);
+
+	return 1;
+}
+
 static int _print_vg(struct formatter *f, struct volume_group *vg)
 {
 	char buffer[4096];
@@ -332,9 +346,8 @@ static int _print_vg(struct formatter *f, struct volume_group *vg)
 
 	outf(f, "seqno = %u", vg->seqno);
 
-	if (!print_flags(vg->status, VG_FLAGS, buffer, sizeof(buffer)))
+	if (!_print_flag_config(f, vg->status, VG_FLAGS))
 		return_0;
-	outf(f, "status = %s", buffer);
 
 	if (!list_empty(&vg->tags)) {
 		if (!print_tags(&vg->tags, buffer, sizeof(buffer)))
@@ -408,9 +421,8 @@ static int _print_pvs(struct formatter *f, struct volume_group *vg)
 			return_0;
 		outnl(f);
 
-		if (!print_flags(pv->status, PV_FLAGS, buffer, sizeof(buffer)))
+		if (!_print_flag_config(f, pv->status, PV_FLAGS))
 			return_0;
-		outf(f, "status = %s", buffer);
 
 		if (!list_empty(&pv->tags)) {
 			if (!print_tags(&pv->tags, buffer, sizeof(buffer)))
@@ -520,9 +532,8 @@ static int _print_lv(struct formatter *f, struct logical_volume *lv)
 
 	outf(f, "id = \"%s\"", buffer);
 
-	if (!print_flags(lv->status, LV_FLAGS, buffer, sizeof(buffer)))
+	if (!_print_flag_config(f, lv->status, LV_FLAGS))
 		return_0;
-	outf(f, "status = %s", buffer);
 
 	if (!list_empty(&lv->tags)) {
 		if (!print_tags(&lv->tags, buffer, sizeof(buffer)))