machined: improve error message when trying to get a bus in bus-less containers

Now that we get useful error messages from sd-bus for container
connections, let's make use of this and report better errors back to
machined clients.

Fixes #685.

diff --git a/src/machine/machine-dbus.c b/src/machine/machine-dbus.c
index fbeace0ed63fac75857ab34aac7077f78e14107c..cc3811670455d1bcdcec480559d3963d16b1c109 100644 (file)
--- a/src/machine/machine-dbus.c
+++ b/src/machine/machine-dbus.c
@@ -519,7 +519,7 @@ int bus_machine_method_open_pty(sd_bus_message *message, void *userdata, sd_bus_
         return sd_bus_send(NULL, reply, NULL);
 }
 
-static int container_bus_new(Machine *m, sd_bus **ret) {
+static int container_bus_new(Machine *m, sd_bus_error *error, sd_bus **ret) {
         int r;
 
         assert(m);
@@ -548,6 +548,8 @@ static int container_bus_new(Machine *m, sd_bus **ret) {
                 bus->is_system = true;
 
                 r = sd_bus_start(bus);
+                if (r == -ENOENT)
+                        return sd_bus_error_set_errnof(error, r, "There is no system bus in container %s.", m->name);
                 if (r < 0)
                         return r;
 
@@ -602,7 +604,7 @@ int bus_machine_method_open_login(sd_bus_message *message, void *userdata, sd_bu
         if (!p)
                 return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "PTS name %s is invalid", pty_name);
 
-        r = container_bus_new(m, &allocated_bus);
+        r = container_bus_new(m, error, &allocated_bus);
         if (r < 0)
                 return r;
 
@@ -704,7 +706,7 @@ int bus_machine_method_open_shell(sd_bus_message *message, void *userdata, sd_bu
         utmp_id = path_startswith(pty_name, "/dev/");
         assert(utmp_id);
 
-        r = container_bus_new(m, &allocated_bus);
+        r = container_bus_new(m, error, &allocated_bus);
         if (r < 0)
                 return r;