From 3790f2e79c4f3e20a41834f1d1138b80342963c2 Mon Sep 17 00:00:00 2001
From: Joe Thornber <ejt@redhat.com>
Date: Tue, 19 Sep 2017 11:05:00 +0100
Subject: [PATCH] [thin_rmap] Fail if no regions are supplied.

---
 thin-provisioning/thin_rmap.cc | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/thin-provisioning/thin_rmap.cc b/thin-provisioning/thin_rmap.cc
index 9f01255..9625530 100644
--- a/thin-provisioning/thin_rmap.cc
+++ b/thin-provisioning/thin_rmap.cc
@@ -180,6 +180,12 @@ thin_rmap_cmd::run(int argc, char **argv)
 		exit(1);
 	}
 
+	if (!regions.size()) {
+		cerr << "No regions provided." << endl;
+		usage(cerr);
+		exit(1);
+	}
+
 	return rmap(argv[optind], regions);
 }