log error when at least one list units request fails

Relates to:
#567
#568

When list units for all nodes is run and the requests are submitted,
it might happen that one of those is failing. Previously, this led
to a failure when reading the message for the node where the request
failed - which got propagated to the caller.
Now, an additional error log in BlueChi is made and the error code
is extracted from the sd_bus_message.
Also removes the top-most error print in the client to avoid printing
errors twice.

Signed-off-by: Michael Engel <[email protected]>

src/client/main.c

@@ -68,7 +68,6 @@ int main(int argc, char *argv[]) {
         _cleanup_client_ Client *client = new_client(op, opargc, opargv, opt_filter_glob);
         r = client_call_manager(client);
         if (r < 0) {
-                fprintf(stderr, "Call to manager failed: %s\n", strerror(-r));
                 return EXIT_FAILURE;
         }
 

src/manager/manager.c

@@ -504,6 +504,12 @@ static int manager_method_list_units_encode_reply(ListUnitsRequest *req, sd_bus_
                         continue;
                 }
 
+                const sd_bus_error *err = sd_bus_message_get_error(m);
+                if (err != NULL) {
+                        bc_log_errorf("Failed to list units for node '%s': %s", node_name, err->message);
+                        return -sd_bus_message_get_errno(m);
+                }
+
                 r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, UNIT_INFO_STRUCT_TYPESTRING);
                 if (r < 0) {
                         return r;
@@ -562,9 +568,6 @@ static void manager_method_list_units_done(ListUnitsRequest *req) {
 
         _cleanup_sd_bus_message_ sd_bus_message *reply = NULL;
         int r = sd_bus_message_new_method_return(req->request_message, &reply);
-        if (r >= 0) {
-                r = manager_method_list_units_encode_reply(req, reply);
-        }
         if (r < 0) {
                 sd_bus_reply_method_errorf(
                                 req->request_message,
@@ -574,6 +577,16 @@ static void manager_method_list_units_done(ListUnitsRequest *req) {
                 return;
         }
 
+        r = manager_method_list_units_encode_reply(req, reply);
+        if (r < 0) {
+                sd_bus_reply_method_errorf(
+                                req->request_message,
+                                SD_BUS_ERROR_FAILED,
+                                "List units request to at least one node failed: %s",
+                                strerror(-r));
+                return;
+        }
+
         r = sd_bus_message_send(reply);
         if (r < 0) {
                 bc_log_errorf("Failed to send reply message: %s", strerror(-r));

src/manager/node.c

@@ -1129,17 +1129,17 @@ int agent_request_start(AgentRequest *req) {
 AgentRequest *node_request_list_units(
                 Node *node, agent_request_response_t cb, void *userdata, free_func_t free_userdata) {
         if (!node_has_agent(node)) {
-                return false;
+                return NULL;
         }
 
         _cleanup_agent_request_ AgentRequest *req = NULL;
         node_create_request(&req, node, "ListUnits", cb, userdata, free_userdata);
         if (req == NULL) {
-                return false;
+                return NULL;
         }
 
         if (agent_request_start(req) < 0) {
-                return false;
+                return NULL;
         }
 
         return steal_pointer(&req);