When the client doesn't support 'async' capability, let's suspend the monitor until the on-going async command completes. That way, the client will be able to use -async commands, but will get only in order reply. (it won't be able to do concurrent commands)
Signed-off-by: Marc-André Lureau <[email protected]> --- monitor.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/monitor.c b/monitor.c index 61abb86..0b47f83 100644 --- a/monitor.c +++ b/monitor.c @@ -174,6 +174,7 @@ typedef struct { */ bool in_command_mode; /* are we in command mode? */ bool has_async; /* the client has async capability */ + QObject *suspended; QmpClient client; } MonitorQMP; @@ -3683,9 +3684,10 @@ static int monitor_can_read(void *opaque) { Monitor *mon = opaque; - return (mon->suspend_cnt == 0) ? 1 : 0; + return (mon->suspend_cnt == 0 && !mon->qmp.suspended) ? 1 : 0; } + static bool invalid_qmp_mode(const Monitor *mon, const char *cmd, Error **errp) { @@ -3762,11 +3764,33 @@ static QDict *qmp_check_input_obj(QObject *input_obj, Error **errp) return input_dict; } +static void monitor_qmp_suspend(Monitor *mon, QObject *req) +{ + assert(monitor_is_qmp(mon)); + assert(!mon->qmp.suspended); + + qobject_incref(req); + mon->qmp.suspended = req; +} + +static void monitor_qmp_resume(Monitor *mon) +{ + assert(monitor_is_qmp(mon)); + assert(mon->qmp.suspended); + + qobject_decref(mon->qmp.suspended); + mon->qmp.suspended = NULL; +} + static void qmp_dispatch_return(QmpClient *client, QObject *rsp) { Monitor *mon = container_of(client, Monitor, qmp.client); monitor_json_emitter(mon, rsp); + + if (mon->qmp.suspended) { + monitor_qmp_resume(mon); + } } static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens) @@ -3805,6 +3829,12 @@ static void handle_qmp_command(JSONMessageParser *parser, GQueue *tokens) } qmp_dispatch(&mon->qmp.client, req, rqdict); + + /* suspend if the command is on-going and client doesn't support async */ + if (!QLIST_EMPTY(&mon->qmp.client.pending) && !mon->qmp.has_async) { + monitor_qmp_suspend(mon, req); + } + qobject_decref(req); return; -- 2.10.0
