From ab958ee752d7faa75967b3d631cf18591852a4f0 Mon Sep 17 00:00:00 2001
From: Thanos Makatos <thanos.makatos@onapp.com>
Date: Thu, 31 Mar 2016 14:20:12 +0300
Subject: [PATCH] improve error message when failing to stat block device

---
 persistent-data/file_utils.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/persistent-data/file_utils.cc b/persistent-data/file_utils.cc
index 88ee945..4853040 100644
--- a/persistent-data/file_utils.cc
+++ b/persistent-data/file_utils.cc
@@ -21,7 +21,8 @@ persistent_data::get_nr_blocks(string const &path, sector_t block_size)
 
 	int r = ::stat(path.c_str(), &info);
 	if (r)
-		throw runtime_error("Couldn't stat dev path");
+		throw runtime_error("Couldn't stat dev path " + path + ": " +
+			strerror(errno));
 
 	if (S_ISREG(info.st_mode) && info.st_size)
 		nr_blocks = div_up<block_address>(info.st_size, block_size);