varlink: add helper that clears the currently processed incoming message JSON object

Some minor refactoring. This adds a helper call whose only job is to
unref the JSON object of the currently processed incoming message.

This doesn't make too much sense on its own, given this just replaces
one line by another. However, in a later patch when we'll add fd passing
we'll extend the function to also destroy associated fds, and then it
will start to make more sense.

diff --git a/src/shared/varlink.c b/src/shared/varlink.c
index fe1cfeb0a1084bc16447b1413ec2c49f5d035713..220442826f65de3bfc92fd5df6eb5c30f7cae1e7 100644 (file)
--- a/src/shared/varlink.c
+++ b/src/shared/varlink.c
@@ -360,6 +360,13 @@ static void varlink_detach_event_sources(Varlink *v) {
         v->defer_event_source = sd_event_source_disable_unref(v->defer_event_source);
 }
 
+static void varlink_clear_current(Varlink *v) {
+        assert(v);
+
+        /* Clears the currently processed incoming message */
+        v->current = json_variant_unref(v->current);
+}
+
 static void varlink_clear(Varlink *v) {
         assert(v);
 
@@ -370,7 +377,7 @@ static void varlink_clear(Varlink *v) {
         v->input_buffer = mfree(v->input_buffer);
         v->output_buffer = mfree(v->output_buffer);
 
-        v->current = json_variant_unref(v->current);
+        varlink_clear_current(v);
 
         v->event = sd_event_unref(v->event);
 }
@@ -760,7 +767,7 @@ static int varlink_dispatch_reply(Varlink *v) {
                                 log_debug_errno(r, "Reply callback returned error, ignoring: %m");
                 }
 
-                v->current = json_variant_unref(v->current);
+                varlink_clear_current(v);
 
                 if (v->state == VARLINK_PROCESSING_REPLY) {
 
@@ -900,7 +907,7 @@ static int varlink_dispatch_method(Varlink *v) {
 
         case VARLINK_PROCESSED_METHOD: /* Method call is fully processed */
         case VARLINK_PROCESSING_METHOD_ONEWAY: /* ditto */
-                v->current = json_variant_unref(v->current);
+                varlink_clear_current(v);
                 varlink_set_state(v, VARLINK_IDLE_SERVER);
                 break;
 
@@ -1476,7 +1483,7 @@ int varlink_call(
 
         assert(v->n_pending == 0); /* n_pending can't be > 0 if we are in VARLINK_IDLE_CLIENT state */
 
-        v->current = json_variant_unref(v->current);
+        varlink_clear_current(v);
 
         r = varlink_sanitize_parameters(&parameters);
         if (r < 0)
@@ -1591,7 +1598,7 @@ int varlink_reply(Varlink *v, JsonVariant *parameters) {
                 /* We just replied to a method call that was let hanging for a while (i.e. we were outside of
                  * the varlink_dispatch_method() stack frame), which means with this reply we are ready to
                  * process further messages. */
-                v->current = json_variant_unref(v->current);
+                varlink_clear_current(v);
                 varlink_set_state(v, VARLINK_IDLE_SERVER);
         } else
                 /* We replied to a method call from within the varlink_dispatch_method() stack frame), which
@@ -1647,7 +1654,7 @@ int varlink_error(Varlink *v, const char *error_id, JsonVariant *parameters) {
                 return varlink_log_errno(v, r, "Failed to enqueue json message: %m");
 
         if (IN_SET(v->state, VARLINK_PENDING_METHOD, VARLINK_PENDING_METHOD_MORE)) {
-                v->current = json_variant_unref(v->current);
+                varlink_clear_current(v);
                 varlink_set_state(v, VARLINK_IDLE_SERVER);
         } else
                 varlink_set_state(v, VARLINK_PROCESSED_METHOD);