[Qemu-devel] [PATCH v4 03/20] qmp: add QmpSession

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

This structure will hold various data related to a QMP client session:
the list of commands, the parser, the callbacks, the pending
operations...

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 include/qapi/qmp/dispatch.h | 10 +++++++++-
 monitor.c                   | 18 ++++++++++--------
 qapi/qmp-dispatch.c         | 15 ++++++++++++---
 qga/main.c                  |  5 ++++-
 tests/test-qmp-cmds.c       | 28 ++++++++++++++++++++++------
 5 files changed, 57 insertions(+), 19 deletions(-)

diff --git a/include/qapi/qmp/dispatch.h b/include/qapi/qmp/dispatch.h
index 5a9cf82472..3b53cfd788 100644
--- a/include/qapi/qmp/dispatch.h
+++ b/include/qapi/qmp/dispatch.h
@@ -37,10 +37,18 @@ typedef struct QmpCommand
 
 typedef QTAILQ_HEAD(QmpCommandList, QmpCommand) QmpCommandList;
 
+typedef struct QmpSession QmpSession;
+
+struct QmpSession {
+    const QmpCommandList *cmds;
+};
+
 void qmp_register_command(QmpCommandList *cmds, const char *name,
                           QmpCommandFunc *fn, QmpCommandOptions options);
 const QmpCommand *qmp_find_command(const QmpCommandList *cmds,
                                    const char *name);
+void qmp_session_init(QmpSession *session, const QmpCommandList *cmds);
+void qmp_session_destroy(QmpSession *session);
 void qmp_disable_command(QmpCommandList *cmds, const char *name);
 void qmp_enable_command(QmpCommandList *cmds, const char *name);
 
@@ -48,7 +56,7 @@ bool qmp_command_is_enabled(const QmpCommand *cmd);
 const char *qmp_command_name(const QmpCommand *cmd);
 bool qmp_has_success_response(const QmpCommand *cmd);
 QDict *qmp_error_response(Error *err);
-QDict *qmp_dispatch(const QmpCommandList *cmds, QObject *request,
+QDict *qmp_dispatch(QmpSession *session, QObject *request,
                     bool allow_oob);
 bool qmp_is_oob(const QDict *dict);
 
diff --git a/monitor.c b/monitor.c
index abc5bdc4ba..a07175b4f8 100644
--- a/monitor.c
+++ b/monitor.c
@@ -174,7 +174,7 @@ typedef struct {
      * qmp_capabilities succeeds, we go into command mode, and
      * @command becomes &qmp_commands.
      */
-    const QmpCommandList *commands;
+    QmpSession session;
     bool capab_offered[QMP_CAPABILITY__MAX]; /* capabilities offered */
     bool capab[QMP_CAPABILITY__MAX];         /* offered and accepted */
     /*
@@ -520,7 +520,7 @@ static void monitor_qapi_event_emit(QAPIEvent event, QDict *qdict)
     trace_monitor_protocol_event_emit(event, qdict);
     QTAILQ_FOREACH(mon, &mon_list, entry) {
         if (monitor_is_qmp(mon)
-            && mon->qmp.commands != &qmp_cap_negotiation_commands) {
+            && mon->qmp.session.cmds != &qmp_cap_negotiation_commands) {
             qmp_send_response(mon, qdict);
         }
     }
@@ -729,6 +729,7 @@ static void monitor_data_destroy(Monitor *mon)
     g_free(mon->mon_cpu_path);
     qemu_chr_fe_deinit(&mon->chr, false);
     if (monitor_is_qmp(mon)) {
+        qmp_session_destroy(&mon->qmp.session);
         json_message_parser_destroy(&mon->qmp.parser);
     }
     readline_free(mon->rs);
@@ -1090,7 +1091,7 @@ CommandInfoList *qmp_query_commands(Error **errp)
 {
     CommandInfoList *list = NULL;
 
-    qmp_for_each_command(cur_mon->qmp.commands, query_commands_cb, &list);
+    qmp_for_each_command(cur_mon->qmp.session.cmds, query_commands_cb, &list);
 
     return list;
 }
@@ -1207,7 +1208,7 @@ static bool qmp_caps_accept(Monitor *mon, QMPCapabilityList *list,
 void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
                           Error **errp)
 {
-    if (cur_mon->qmp.commands == &qmp_commands) {
+    if (cur_mon->qmp.session.cmds == &qmp_commands) {
         error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
                   "Capabilities negotiation is already complete, command "
                   "ignored");
@@ -1218,7 +1219,7 @@ void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
         return;
     }
 
-    cur_mon->qmp.commands = &qmp_commands;
+    cur_mon->qmp.session.cmds = &qmp_commands;
 }
 
 /* Set the current CPU defined by the user. Callers must hold BQL. */
@@ -4121,11 +4122,11 @@ static void monitor_qmp_dispatch(Monitor *mon, QObject *req)
     old_mon = cur_mon;
     cur_mon = mon;
 
-    rsp = qmp_dispatch(mon->qmp.commands, req, qmp_oob_enabled(mon));
+    rsp = qmp_dispatch(&mon->qmp.session, req, qmp_oob_enabled(mon));
 
     cur_mon = old_mon;
 
-    if (mon->qmp.commands == &qmp_cap_negotiation_commands) {
+    if (mon->qmp.session.cmds == &qmp_cap_negotiation_commands) {
         error = qdict_get_qdict(rsp, "error");
         if (error
             && !g_strcmp0(qdict_get_try_str(error, "class"),
@@ -4399,7 +4400,7 @@ static void monitor_qmp_event(void *opaque, int event)
 
     switch (event) {
     case CHR_EVENT_OPENED:
-        mon->qmp.commands = &qmp_cap_negotiation_commands;
+        qmp_session_init(&mon->qmp.session, &qmp_cap_negotiation_commands);
         monitor_qmp_caps_reset(mon);
         data = qmp_greeting(mon);
         qmp_send_response(mon, data);
@@ -4414,6 +4415,7 @@ static void monitor_qmp_event(void *opaque, int event)
          * is closed.
          */
         monitor_qmp_cleanup_queues(mon);
+        qmp_session_destroy(&mon->qmp.session);
         json_message_parser_destroy(&mon->qmp.parser);
         json_message_parser_init(&mon->qmp.parser, handle_qmp_command,
                                  mon, NULL);
diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c
index f9d43046aa..98a82ac33c 100644
--- a/qapi/qmp-dispatch.c
+++ b/qapi/qmp-dispatch.c
@@ -163,15 +163,24 @@ bool qmp_is_oob(const QDict *dict)
         && !qdict_haskey(dict, "execute");
 }
 
-QDict *qmp_dispatch(const QmpCommandList *cmds, QObject *request,
-                    bool allow_oob)
+void qmp_session_init(QmpSession *session, const QmpCommandList *cmds)
+{
+    session->cmds = cmds;
+}
+
+void qmp_session_destroy(QmpSession *session)
+{
+    session->cmds = NULL;
+}
+
+QDict *qmp_dispatch(QmpSession *session, QObject *request, bool allow_oob)
 {
     Error *err = NULL;
     QDict *dict = qobject_to(QDict, request);
     QObject *ret, *id = dict ? qdict_get(dict, "id") : NULL;
     QDict *rsp;
 
-    ret = do_qmp_dispatch(cmds, request, allow_oob, &err);
+    ret = do_qmp_dispatch(session->cmds, request, allow_oob, &err);
     if (err) {
         rsp = qmp_error_response(err);
     } else if (ret) {
diff --git a/qga/main.c b/qga/main.c
index 5b144b9250..bf0082df90 100644
--- a/qga/main.c
+++ b/qga/main.c
@@ -74,6 +74,7 @@ typedef struct GAPersistentState {
 typedef struct GAConfig GAConfig;
 
 struct GAState {
+    QmpSession session;
     JSONMessageParser parser;
     GMainLoop *main_loop;
     GAChannel *channel;
@@ -572,7 +573,7 @@ static void process_event(void *opaque, QObject *obj, Error *err)
     }
 
     g_debug("processing command");
-    rsp = qmp_dispatch(&ga_commands, obj, false);
+    rsp = qmp_dispatch(&s->session, obj, false);
 
 end:
     ret = send_response(s, rsp);
@@ -1338,6 +1339,7 @@ static GAState *initialize_agent(GAConfig *config, int socket_activation)
     ga_command_state_init(s, s->command_state);
     ga_command_state_init_all(s->command_state);
     json_message_parser_init(&s->parser, process_event, s, NULL);
+    qmp_session_init(&s->session, &ga_commands);
 
 #ifndef _WIN32
     if (!register_signal_handlers()) {
@@ -1369,6 +1371,7 @@ static void cleanup_agent(GAState *s)
     CloseHandle(s->wakeup_event);
 #endif
     if (s->command_state) {
+        qmp_session_destroy(&s->session);
         ga_command_state_cleanup_all(s->command_state);
         ga_command_state_free(s->command_state);
         json_message_parser_destroy(&s->parser);
diff --git a/tests/test-qmp-cmds.c b/tests/test-qmp-cmds.c
index 630b1b9bac..7c39ec1657 100644
--- a/tests/test-qmp-cmds.c
+++ b/tests/test-qmp-cmds.c
@@ -113,44 +113,52 @@ __org_qemu_x_Union1 *qmp___org_qemu_x_command(__org_qemu_x_EnumList *a,
 /* test commands with no input and no return value */
 static void test_dispatch_cmd(void)
 {
+    QmpSession session = { 0, };
     QDict *req = qdict_new();
     QDict *resp;
 
+    qmp_session_init(&session, &qmp_commands);
     qdict_put_str(req, "execute", "user_def_cmd");
 
-    resp = qmp_dispatch(&qmp_commands, QOBJECT(req), false);
+    resp = qmp_dispatch(&session, QOBJECT(req), false);
     assert(resp != NULL);
     assert(!qdict_haskey(resp, "error"));
 
     qobject_unref(resp);
     qobject_unref(req);
+    qmp_session_destroy(&session);
 }
 
 static void test_dispatch_cmd_oob(void)
 {
+    QmpSession session = { 0, };
     QDict *req = qdict_new();
     QDict *resp;
 
+    qmp_session_init(&session, &qmp_commands);
     qdict_put_str(req, "exec-oob", "test-flags-command");
 
-    resp = qmp_dispatch(&qmp_commands, QOBJECT(req), true);
+    resp = qmp_dispatch(&session, QOBJECT(req), true);
     assert(resp != NULL);
     assert(!qdict_haskey(resp, "error"));
 
     qobject_unref(resp);
     qobject_unref(req);
+    qmp_session_destroy(&session);
 }
 
 /* test commands that return an error due to invalid parameters */
 static void test_dispatch_cmd_failure(void)
 {
+    QmpSession session = { 0, };
     QDict *req = qdict_new();
     QDict *args = qdict_new();
     QDict *resp;
 
+    qmp_session_init(&session, &qmp_commands);
     qdict_put_str(req, "execute", "user_def_cmd2");
 
-    resp = qmp_dispatch(&qmp_commands, QOBJECT(req), false);
+    resp = qmp_dispatch(&session, QOBJECT(req), false);
     assert(resp != NULL);
     assert(qdict_haskey(resp, "error"));
 
@@ -164,36 +172,44 @@ static void test_dispatch_cmd_failure(void)
 
     qdict_put_str(req, "execute", "user_def_cmd");
 
-    resp = qmp_dispatch(&qmp_commands, QOBJECT(req), false);
+    resp = qmp_dispatch(&session, QOBJECT(req), false);
     assert(resp != NULL);
     assert(qdict_haskey(resp, "error"));
 
     qobject_unref(resp);
     qobject_unref(req);
+    qmp_session_destroy(&session);
 }
 
 static void test_dispatch_cmd_success_response(void)
 {
+    QmpSession session = { 0, };
     QDict *req = qdict_new();
     QDict *resp;
 
+    qmp_session_init(&session, &qmp_commands);
     qdict_put_str(req, "execute", "cmd-success-response");
-    resp = qmp_dispatch(&qmp_commands, QOBJECT(req), false);
+    resp = qmp_dispatch(&session, QOBJECT(req), false);
     g_assert_null(resp);
     qobject_unref(req);
+    qmp_session_destroy(&session);
 }
 
+
 static QObject *test_qmp_dispatch(QDict *req)
 {
+    QmpSession session = { 0, };
     QDict *resp;
     QObject *ret;
 
-    resp = qmp_dispatch(&qmp_commands, QOBJECT(req), false);
+    qmp_session_init(&session, &qmp_commands);
+    resp = qmp_dispatch(&session, QOBJECT(req), false);
     assert(resp && !qdict_haskey(resp, "error"));
     ret = qdict_get(resp, "return");
     assert(ret);
     qobject_ref(ret);
     qobject_unref(resp);
+    qmp_session_destroy(&session);
     return ret;
 }
 
-- 
2.21.0.196.g041f5ea1cf