From 66ae5130a0ecf72b42503abe68c865e97ab512fd Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 11 Jun 2018 12:03:35 +0200
Subject: [PATCH] blockdev-util: let's initialize return parameter on success

We document the rule that return values >= 0 of functions are supposed
to indicate success, and that in case of success all return parameters
should be initialized. Let's actually do so.

Just a tiny coding style fix-up.
---
 src/basic/blockdev-util.c | 1 +
 src/basic/btrfs-util.c    | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/basic/blockdev-util.c b/src/basic/blockdev-util.c
index b15b8cf770..6495a71658 100644
--- a/src/basic/blockdev-util.c
+++ b/src/basic/blockdev-util.c
@@ -81,6 +81,7 @@ int get_block_device(const char *path, dev_t *dev) {
         if (F_TYPE_EQUAL(sfs.f_type, BTRFS_SUPER_MAGIC))
                 return btrfs_get_block_device(path, dev);
 
+        *dev = 0;
         return 0;
 }
 
diff --git a/src/basic/btrfs-util.c b/src/basic/btrfs-util.c
index 7720d98009..32a022f7ce 100644
--- a/src/basic/btrfs-util.c
+++ b/src/basic/btrfs-util.c
@@ -277,8 +277,10 @@ int btrfs_get_block_device_fd(int fd, dev_t *dev) {
                 return -errno;
 
         /* We won't do this for btrfs RAID */
-        if (fsi.num_devices != 1)
+        if (fsi.num_devices != 1) {
+                *dev = 0;
                 return 0;
+        }
 
         for (id = 1; id <= fsi.max_id; id++) {
                 struct btrfs_ioctl_dev_info_args di = {