qapi: add support for command options
Options allow for changes in commands behavior. This commit introduces
the QCO_NO_SUCCESS_RESP option, which causes a command to not emit a
success response.
This is needed by commands such as qemu-ga's guest-shutdown, which
may not be able to complete before the VM vanishes. In this case, it's
useful and simpler not to bother sending a success response.
Signed-off-by: Luiz Capitulino <[email protected]>
Signed-off-by: Michael Roth <[email protected]>
diff --git a/qapi/qmp-core.h b/qapi/qmp-core.h
index 431ddbb..b0f64ba 100644
--- a/qapi/qmp-core.h
+++ b/qapi/qmp-core.h
@@ -25,16 +25,24 @@
QCT_NORMAL,
} QmpCommandType;
+typedef enum QmpCommandOptions
+{
+ QCO_NO_OPTIONS = 0x0,
+ QCO_NO_SUCCESS_RESP = 0x1,
+} QmpCommandOptions;
+
typedef struct QmpCommand
{
const char *name;
QmpCommandType type;
QmpCommandFunc *fn;
+ QmpCommandOptions options;
QTAILQ_ENTRY(QmpCommand) node;
bool enabled;
} QmpCommand;
-void qmp_register_command(const char *name, QmpCommandFunc *fn);
+void qmp_register_command(const char *name, QmpCommandFunc *fn,
+ QmpCommandOptions options);
QmpCommand *qmp_find_command(const char *name);
QObject *qmp_dispatch(QObject *request);
void qmp_disable_command(const char *name);
diff --git a/qapi/qmp-dispatch.c b/qapi/qmp-dispatch.c
index 43f640a..122c1a2 100644
--- a/qapi/qmp-dispatch.c
+++ b/qapi/qmp-dispatch.c
@@ -94,8 +94,12 @@
switch (cmd->type) {
case QCT_NORMAL:
cmd->fn(args, &ret, errp);
- if (!error_is_set(errp) && ret == NULL) {
- ret = QOBJECT(qdict_new());
+ if (!error_is_set(errp)) {
+ if (cmd->options & QCO_NO_SUCCESS_RESP) {
+ g_assert(!ret);
+ } else if (!ret) {
+ ret = QOBJECT(qdict_new());
+ }
}
break;
}
diff --git a/qapi/qmp-registry.c b/qapi/qmp-registry.c
index 43d5cde..5414613 100644
--- a/qapi/qmp-registry.c
+++ b/qapi/qmp-registry.c
@@ -17,7 +17,8 @@
static QTAILQ_HEAD(QmpCommandList, QmpCommand) qmp_commands =
QTAILQ_HEAD_INITIALIZER(qmp_commands);
-void qmp_register_command(const char *name, QmpCommandFunc *fn)
+void qmp_register_command(const char *name, QmpCommandFunc *fn,
+ QmpCommandOptions options)
{
QmpCommand *cmd = g_malloc0(sizeof(*cmd));
@@ -25,6 +26,7 @@
cmd->type = QCT_NORMAL;
cmd->fn = fn;
cmd->enabled = true;
+ cmd->options = options;
QTAILQ_INSERT_TAIL(&qmp_commands, cmd, node);
}
