[PATCH v2 3/4] qmp: Allow setting -action parameters on the fly

[Alejandro Jimenez]

Add a QMP command to allow for the behaviors specified by the
-action event=action command line option to be set at runtime.
The new command is named set-action, and takes a single argument
of type RunStateAction, which contains an event|action pair.

Example:

-> { "execute": "set-action",
     "arguments": { "pair": {
         "event": "shutdown",
          "action": "pause" } } }
<- { "return": {} }

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
---
 qapi/run-state.json       | 22 ++++++++++++++++++++++
 softmmu/runstate-action.c | 29 +++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/qapi/run-state.json b/qapi/run-state.json
index 27b62ce..ead9dab 100644
--- a/qapi/run-state.json
+++ b/qapi/run-state.json
@@ -451,6 +451,28 @@
 { 'command': 'watchdog-set-action', 'data' : {'action': 'WatchdogAction'} }
 
 ##
+# @set-action:
+#
+# Set the action that will be taken by the emulator in response to a guest
+# event.
+#
+# @pair: a @RunStateAction type that describes an event|action pair.
+#
+# Returns: Nothing on success.
+#
+# Since: 6.0
+#
+# Example:
+#
+# -> { "execute": "set-action",
+#         "arguments": { "pair": {
+#             "event": "shutdown",
+#             "action": "pause" } } }
+# <- { "return": {} }
+##
+{ 'command': 'set-action', 'data' : {'pair': 'RunStateAction'} }
+
+##
 # @GUEST_PANICKED:
 #
 # Emitted when guest OS panic is detected
diff --git a/softmmu/runstate-action.c b/softmmu/runstate-action.c
index a644d80..7877e7e 100644
--- a/softmmu/runstate-action.c
+++ b/softmmu/runstate-action.c
@@ -80,6 +80,35 @@ static void panic_set_action(PanicAction action, Error 
**errp)
 }
 
 /*
+ * Receives a RunStateAction type which represents an event|action pair
+ * and sets the internal state as requested.
+ */
+void qmp_set_action(RunStateAction *pair, Error **errp)
+{
+    switch (pair->event) {
+    case RUN_STATE_EVENT_TYPE_REBOOT:
+        reboot_set_action(pair->u.reboot.action, NULL);
+        break;
+    case RUN_STATE_EVENT_TYPE_SHUTDOWN:
+        shutdown_set_action(pair->u.shutdown.action, NULL);
+        break;
+    case RUN_STATE_EVENT_TYPE_PANIC:
+        panic_set_action(pair->u.panic.action, NULL);
+        break;
+    case RUN_STATE_EVENT_TYPE_WATCHDOG:
+        qmp_watchdog_set_action(pair->u.watchdog.action, NULL);
+        break;
+    default:
+        /*
+         * The fields in the RunStateAction argument are validated
+         * by the QMP marshalling code before this function is called.
+         * This case is unreachable unless new variants are added.
+         */
+        g_assert_not_reached();
+    }
+}
+
+/*
  * Process an event|action pair and set the appropriate internal
  * state if event and action are valid.
  */
-- 
1.8.3.1