diff mbox series

[v2,20/37] libmultipath: dm_get_uuid(): return emtpy UUID for non-existing maps

Message ID 20230911163846.27197-21-mwilck@suse.com (mailing list archive)
State Not Applicable, archived
Delegated to: christophe varoqui
Headers show
Series multipath-tools: user-friendly names rework | expand

Commit Message

Martin Wilck Sept. 11, 2023, 4:38 p.m. UTC 
From: Martin Wilck <mwilck@suse.com>

libdevmapper will most probably not return a UUID for non-existing
maps anyway. But it's cheap to double-check here.

Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
---
 libmultipath/devmapper.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/libmultipath/devmapper.c b/libmultipath/devmapper.c
index 248c373..9be82f4 100644
--- a/libmultipath/devmapper.c
+++ b/libmultipath/devmapper.c
@@ -706,12 +706,16 @@  dm_get_prefixed_uuid(const char *name, char *uuid, int uuid_len)
 {
 	struct dm_task *dmt;
 	const char *uuidtmp;
+	struct dm_info info;
 	int r = 1;
 
 	dmt = libmp_dm_task_create(DM_DEVICE_INFO);
 	if (!dmt)
 		return 1;
 
+	if (uuid_len > 0)
+		uuid[0] = '\0';
+
 	if (!dm_task_set_name (dmt, name))
 		goto uuidout;
 
@@ -720,11 +724,13 @@  dm_get_prefixed_uuid(const char *name, char *uuid, int uuid_len)
 		goto uuidout;
 	}
 
+	if (!dm_task_get_info(dmt, &info) ||
+	    !info.exists)
+		goto uuidout;
+
 	uuidtmp = dm_task_get_uuid(dmt);
 	if (uuidtmp)
 		strlcpy(uuid, uuidtmp, uuid_len);
-	else
-		uuid[0] = '\0';
 
 	r = 0;
 uuidout: