[03/24] qmp: teach qmp_dispatch() to take a pre-filled QDict

diff --git a/monitor.c b/monitor.c
index 4ff74b7..f485ebf 100644
--- a/monitor.c
+++ b/monitor.c
@@ -3732,12 +3732,13 @@  static QDict *qmp_check_input_obj(QObject *input_obj, Error **errp)
 
 static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens)
 {
-    QObject *req, *rsp = NULL, *id = NULL;
-    QDict *qdict = NULL;
+    QObject *req, *rsp, *id = NULL;
+    QDict *qdict, *rqdict = qdict_new();
     const char *cmd_name;
     Monitor *mon = cur_mon;
     Error *err = NULL;
 
+    rsp = QOBJECT(rqdict);
     req = json_parser_parse_err(tokens, NULL, &err);
     if (err || !req || qobject_type(req) != QTYPE_QDICT) {
         if (!err) {
@@ -3752,8 +3753,11 @@  static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens)
     }
 
     id = qdict_get(qdict, "id");
-    qobject_incref(id);
-    qdict_del(qdict, "id");
+    if (id) {
+        qobject_incref(id);
+        qdict_del(qdict, "id");
+        qdict_put_obj(rqdict, "id", id);
+    }
 
     cmd_name = qdict_get_str(qdict, "execute");
     trace_handle_qmp_command(mon, cmd_name);
@@ -3762,27 +3766,19 @@  static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens)
         goto err_out;
     }
 
-    rsp = qmp_dispatch(req);
+    rsp = qmp_dispatch(req, rqdict);
 
 err_out:
     if (err) {
-        qdict = qdict_new();
-        qdict_put_obj(qdict, "error", qmp_build_error_object(err));
+        qdict_put_obj(rqdict, "error", qmp_build_error_object(err));
         error_free(err);
-        rsp = QOBJECT(qdict);
     }
 
     if (rsp) {
-        if (id) {
-            qdict_put_obj(qobject_to_qdict(rsp), "id", id);
-            id = NULL;
-        }
-
         monitor_json_emitter(mon, rsp);
     }
 
-    qobject_decref(id);
-    qobject_decref(rsp);
+    QDECREF(rqdict);
     qobject_decref(req);
 }
 
diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c
index 505eb41..dbf2e5b 100644
--- a/qapi/qmp-dispatch.c
+++ b/qapi/qmp-dispatch.c
@@ -116,15 +116,14 @@  QObject *qmp_build_error_object(Error *err)
                               error_get_pretty(err));
 }
 
-QObject *qmp_dispatch(QObject *request)
+QObject *qmp_dispatch(QObject *request, QDict *rsp)
 {
     Error *err = NULL;
     QObject *ret;
-    QDict *rsp;
 
     ret = do_qmp_dispatch(request, &err);
 
-    rsp = qdict_new();
+    rsp = rsp ?: qdict_new();
     if (err) {
         qdict_put_obj(rsp, "error", qmp_build_error_object(err));
         error_free(err);
diff --git a/qga/main.c b/qga/main.c
index 0b9d04e..d236e0e 100644
--- a/qga/main.c
+++ b/qga/main.c
@@ -555,7 +555,7 @@  static void process_command(GAState *s, QDict *req)
 
     g_assert(req);
     g_debug("processing command");
-    rsp = qmp_dispatch(QOBJECT(req));
+    rsp = qmp_dispatch(QOBJECT(req), NULL);
     if (rsp) {
         ret = send_response(s, rsp);
         if (ret) {
diff --git a/tests/test-qmp-commands.c b/tests/test-qmp-commands.c
index 5ff2f9b..1adc1a2 100644
--- a/tests/test-qmp-commands.c
+++ b/tests/test-qmp-commands.c
@@ -94,7 +94,7 @@  static void test_dispatch_cmd(void)
 
     qdict_put_obj(req, "execute", QOBJECT(qstring_from_str("user_def_cmd")));
 
-    resp = qmp_dispatch(QOBJECT(req));
+    resp = qmp_dispatch(QOBJECT(req), NULL);
     assert(resp != NULL);
     assert(!qdict_haskey(qobject_to_qdict(resp), "error"));
 
@@ -111,7 +111,7 @@  static void test_dispatch_cmd_failure(void)
 
     qdict_put_obj(req, "execute", QOBJECT(qstring_from_str("user_def_cmd2")));
 
-    resp = qmp_dispatch(QOBJECT(req));
+    resp = qmp_dispatch(QOBJECT(req), NULL);
     assert(resp != NULL);
     assert(qdict_haskey(qobject_to_qdict(resp), "error"));
 
@@ -125,7 +125,7 @@  static void test_dispatch_cmd_failure(void)
 
     qdict_put_obj(req, "execute", QOBJECT(qstring_from_str("user_def_cmd")));
 
-    resp = qmp_dispatch(QOBJECT(req));
+    resp = qmp_dispatch(QOBJECT(req), NULL);
     assert(resp != NULL);
     assert(qdict_haskey(qobject_to_qdict(resp), "error"));
 
@@ -139,7 +139,7 @@  static QObject *test_qmp_dispatch(QDict *req)
     QDict *resp;
     QObject *ret;
 
-    resp_obj = qmp_dispatch(QOBJECT(req));
+    resp_obj = qmp_dispatch(QOBJECT(req), NULL);
     assert(resp_obj);
     resp = qobject_to_qdict(resp_obj);
     assert(resp && !qdict_haskey(resp, "error"));
diff --git a/include/qapi/qmp/dispatch.h b/include/qapi/qmp/dispatch.h
index 57651ea..db48348 100644
--- a/include/qapi/qmp/dispatch.h
+++ b/include/qapi/qmp/dispatch.h
@@ -38,7 +38,7 @@  void qmp_register_command(const char *name, QmpCommandFunc *fn,
                           QmpCommandOptions options);
 void qmp_unregister_command(const char *name);
 QmpCommand *qmp_find_command(const char *name);
-QObject *qmp_dispatch(QObject *request);
+QObject *qmp_dispatch(QObject *request, QDict *rsp);
 void qmp_disable_command(const char *name);
 void qmp_enable_command(const char *name);
 bool qmp_command_is_enabled(const QmpCommand *cmd);