From 91b7e06865d8f630f2ac9e07435ba92520248af4 Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: May 20 2014 17:28:10 +0000
Subject: qemu: snapshot: Forbid empty snapshots


If neither disks nor memory are selected for snapshot we'd record
metadata in case of external snapshot and do a disk snapshot in case of
external disk snapshot. Forbid this as it doesn't make much sense.

---

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 936e7bd..9dbfc07 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -12703,6 +12703,13 @@ qemuDomainSnapshotPrepare(virConnectPtr conn,
         }
     }
 
+    if (!found_internal && !external &&
+        def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_NONE) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("nothing selected for snapshot"));
+        goto cleanup;
+    }
+
     /* internal snapshot requires a disk image to store the memory image to, and
      * also disks can't be excluded from an internal snapshot*/
     if ((def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL && !found_internal) ||