[PATCH v3 09/11] tests/migration-tests: migration_event_wait()

[Peter Xu <peterx@redhat.com>]

Introduce a small helper to wait for a migration event, generalized from
the incoming migration path.  Make the helper easier to use by allowing it
to keep waiting until the expected event is received.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 tests/qtest/migration-helpers.h |  2 ++
 tests/qtest/migration-helpers.c | 31 ++++++++++++++++++++++---------
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/tests/qtest/migration-helpers.h b/tests/qtest/migration-helpers.h
index 50095fca4a..72dba369fb 100644
--- a/tests/qtest/migration-helpers.h
+++ b/tests/qtest/migration-helpers.h
@@ -63,4 +63,6 @@ static inline bool probe_o_direct_support(const char *tmpfs)
 }
 #endif
 void migration_test_add(const char *path, void (*fn)(void));
+void migration_event_wait(QTestState *s, const char *target);
+
 #endif /* MIGRATION_HELPERS_H */
diff --git a/tests/qtest/migration-helpers.c b/tests/qtest/migration-helpers.c
index 2ca4425d71..84f49db85e 100644
--- a/tests/qtest/migration-helpers.c
+++ b/tests/qtest/migration-helpers.c
@@ -249,7 +249,7 @@ void migrate_set_capability(QTestState *who, const char *capability,
 void migrate_incoming_qmp(QTestState *to, const char *uri, const char *fmt, ...)
 {
     va_list ap;
-    QDict *args, *rsp, *data;
+    QDict *args, *rsp;
 
     va_start(ap, fmt);
     args = qdict_from_vjsonf_nofail(fmt, ap);
@@ -272,14 +272,7 @@ void migrate_incoming_qmp(QTestState *to, const char *uri, const char *fmt, ...)
     g_assert(qdict_haskey(rsp, "return"));
     qobject_unref(rsp);
 
-    rsp = qtest_qmp_eventwait_ref(to, "MIGRATION");
-    g_assert(qdict_haskey(rsp, "data"));
-
-    data = qdict_get_qdict(rsp, "data");
-    g_assert(qdict_haskey(data, "status"));
-    g_assert_cmpstr(qdict_get_str(data, "status"), ==, "setup");
-
-    qobject_unref(rsp);
+    migration_event_wait(to, "setup");
 }
 
 /*
@@ -518,3 +511,23 @@ bool probe_o_direct_support(const char *tmpfs)
     return true;
 }
 #endif
+
+/*
+ * Wait for a "MIGRATION" event.  This is what Libvirt uses to track
+ * migration status changes.
+ */
+void migration_event_wait(QTestState *s, const char *target)
+{
+    QDict *response, *data;
+    const char *status;
+    bool found;
+
+    do {
+        response = qtest_qmp_eventwait_ref(s, "MIGRATION");
+        data = qdict_get_qdict(response, "data");
+        g_assert(data);
+        status = qdict_get_str(data, "status");
+        found = (strcmp(status, target) == 0);
+        qobject_unref(response);
+    } while (!found);
+}
-- 
2.45.0