[Qemu-devel] [PATCH v2 06/25] qmp: add qmp_return_is_cancelled()

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

If the client is gone, no need to return. The async handler can use this
information to avoid unnecessary work and exit earlier.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qapi/qmp/dispatch.h |  8 ++++++++
 qapi/qmp-dispatch.c         | 10 ++++++++++
 2 files changed, 18 insertions(+)

diff --git a/include/qapi/qmp/dispatch.h b/include/qapi/qmp/dispatch.h
index 32876764f3..bc64d4ed15 100644
--- a/include/qapi/qmp/dispatch.h
+++ b/include/qapi/qmp/dispatch.h
@@ -78,4 +78,12 @@ void qmp_for_each_command(qmp_cmd_callback_fn fn, void *opaque);
 void qmp_return(QmpReturn *qret, QObject *cmd_rsp);
 void qmp_return_error(QmpReturn *qret, Error *err);
 
+/*
+ * qmp_return_is_cancelled:
+ *
+ * Return true if the QmpReturn is cancelled, and free the QmpReturn
+ * in this case.
+ */
+bool qmp_return_is_cancelled(QmpReturn *qret);
+
 #endif
diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c
index 31227ce6e9..6ceece5ef0 100644
--- a/qapi/qmp-dispatch.c
+++ b/qapi/qmp-dispatch.c
@@ -155,6 +155,16 @@ void qmp_return_error(QmpReturn *qret, Error *err)
     do_qmp_return(qret);
 }
 
+bool qmp_return_is_cancelled(QmpReturn *qret)
+{
+    if (!qret->client) {
+        qmp_return_free(qret);
+        return true;
+    }
+
+    return false;
+}
+
 void qmp_client_init(QmpClient *client, QmpDispatchReturn *return_cb)
 {
     assert(!client->return_cb);
-- 
2.11.0.295.gd7dffce1c