Error out cleanly when autoclone or destination file is not specified

When virt-clone is used without autoclone or destination file, libvirt
errors with message "ERROR    missing source information for device vda".
This doesn't convey what is missing. This patch will indicate which
options to use.

Signed-off-by: Kothapally Madhu Pavan <kmp@linux.vnet.ibm.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/virt-clone b/virt-clone
index 00d0e30e..905c91ed 100755
--- a/virt-clone
+++ b/virt-clone
@@ -168,6 +168,12 @@ def main(conn=None):
     if conn is None:
         conn = cli.getConnection(options.connect)
 
+    if (options.new_diskfile is None and
+        options.auto_clone is False and
+        options.xmlonly is False):
+        fail(_("Either --auto-clone or --file is required,"
+               " use '--auto-clone or --file' and try again."))
+
     design = Cloner(conn)
 
     design.clone_running = options.clone_running