spice: fix libvirt snapshots

Only notify spice-server about migration events in case we got
target host information beforehand.  So we kick the seamless spice
client migration only in case a actual live migration happens, not
when libvirt uses live-migration-to-file for snapshotting.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

ui/spice-core.c

diff --git a/ui/spice-core.c b/ui/spice-core.c
index 6825579..d10818a 100644
--- a/ui/spice-core.c
+++ b/ui/spice-core.c
@@ -48,6 +48,7 @@
 static time_t auth_expires = TIME_MAX;
 static int spice_migration_completed;
 static int spice_display_is_running;
+static int spice_have_target_host;
 int using_spice = 0;
 
 static QemuThread me;
@@ -564,12 +565,18 @@
 {
     MigrationState *s = data;
 
+    if (!spice_have_target_host) {
+        return;
+    }
+
     if (migration_in_setup(s)) {
         spice_server_migrate_start(spice_server);
     } else if (migration_has_finished(s)) {
         spice_server_migrate_end(spice_server, true);
+        spice_have_target_host = false;
     } else if (migration_has_failed(s)) {
         spice_server_migrate_end(spice_server, false);
+        spice_have_target_host = false;
     }
 }
 
@@ -583,6 +590,7 @@
     spice_migrate.connect_complete.opaque = opaque;
     ret = spice_server_migrate_connect(spice_server, hostname,
                                        port, tls_port, subject);
+    spice_have_target_host = true;
     return ret;
 }