broadband-modem-mbim: log hex value of IP type if unknown

The L850 seems to report 0xFFFFFFFF as MbimContextIpType value, which
is not a correct value.

Instead of printing "(none)" (the default used by glib when trying to
print a NULL pointer as a string), make it so that we end up printing
the actual numeric value in hex.

   <dbg> [modem0] 'home' settings found at configuration index 0
   <dbg> [modem0] 'non-partner' settings found at configuration index 1
   <dbg> [modem0] 'partner' settings not found
   <dbg> [modem0] updates in the home LTE attach configuration settings:
   <dbg> [modem0]   ip type: 'unknown (0xffffffff)' -> ''ipv4v6'
   <dbg> [modem0] updates in the partner LTE attach configuration settings:
   <dbg> [modem0]   none (skipped)
   <dbg> [modem0] updates in the non-partner LTE attach configuration settings:
   <dbg> [modem0]   none

src/mm-broadband-modem-mbim.c

@@ -4443,16 +4443,26 @@ update_lte_attach_configuration (MMBroadbandModemMbim               *self,
     }
 
     if (!previous_config || !new_config || (previous_config->ip_type != new_config->ip_type)) {
+        g_autofree gchar *previous_ip_type = NULL;
+        g_autofree gchar *new_ip_type = NULL;
+
+        previous_ip_type = previous_config ? mm_mbim_context_ip_type_get_printable (previous_config->ip_type) : NULL;
+        new_ip_type = new_config ? mm_mbim_context_ip_type_get_printable (new_config->ip_type) : NULL;
         mm_obj_dbg (self, "  ip type: '%s' -> '%s'",
-                    previous_config ? mbim_context_ip_type_get_string (previous_config->ip_type) : "",
-                    new_config ? mbim_context_ip_type_get_string (new_config->ip_type) : "");
+                    previous_ip_type ? previous_ip_type : "",
+                    new_ip_type ? new_ip_type : "");
         n_updates++;
     }
 
     if (!previous_config || !new_config || (previous_config->auth_protocol != new_config->auth_protocol)) {
+        g_autofree gchar *previous_auth_protocol = NULL;
+        g_autofree gchar *new_auth_protocol = NULL;
+
+        previous_auth_protocol = previous_config ? mm_mbim_auth_protocol_get_printable (previous_config->auth_protocol) : NULL;
+        new_auth_protocol = new_config ? mm_mbim_auth_protocol_get_printable (new_config->auth_protocol) : NULL;
         mm_obj_dbg (self, "  auth protocol: '%s' -> '%s'",
-                    previous_config ? mbim_auth_protocol_get_string (previous_config->auth_protocol) : "",
-                    new_config ? mbim_auth_protocol_get_string (new_config->auth_protocol) : "");
+                    previous_auth_protocol ? previous_auth_protocol : "",
+                    new_auth_protocol ? new_auth_protocol : "");
         n_updates++;
     }
 

src/mm-modem-helpers-mbim.c

@@ -457,6 +457,18 @@ mm_bearer_allowed_auth_to_mbim_auth_protocol (MMBearerAllowedAuth   bearer_auth,
     return MBIM_AUTH_PROTOCOL_NONE;
 }
 
+gchar *
+mm_mbim_auth_protocol_get_printable (MbimAuthProtocol auth_protocol)
+{
+    const gchar *str;
+
+    str = mbim_auth_protocol_get_string (auth_protocol);
+    if (str)
+        return g_strdup (str);
+
+    return g_strdup_printf ("unknown (0x%x)", auth_protocol);
+}
+
 /*****************************************************************************/
 
 MMBearerApnType
@@ -617,6 +629,18 @@ mm_bearer_ip_family_to_mbim_context_ip_type (MMBearerIpFamily   ip_family,
     return MBIM_CONTEXT_IP_TYPE_DEFAULT;
 }
 
+gchar *
+mm_mbim_context_ip_type_get_printable (MbimContextIpType ip_type)
+{
+    const gchar *str;
+
+    str = mbim_context_ip_type_get_string (ip_type);
+    if (str)
+        return g_strdup (str);
+
+    return g_strdup_printf ("unknown (0x%x)", ip_type);
+}
+
 /*****************************************************************************/
 
 gboolean

src/mm-modem-helpers-mbim.h

@@ -60,9 +60,11 @@ MMBearerAllowedAuth mm_bearer_allowed_auth_from_mbim_auth_protocol (MbimAuthProt
 MbimAuthProtocol    mm_bearer_allowed_auth_to_mbim_auth_protocol   (MMBearerAllowedAuth   bearer_auth,
                                                                     gpointer              log_object,
                                                                     GError              **error);
+gchar              *mm_mbim_auth_protocol_get_printable            (MbimAuthProtocol      auth_protocol);
 MMBearerIpFamily    mm_bearer_ip_family_from_mbim_context_ip_type  (MbimContextIpType     ip_type);
 MbimContextIpType   mm_bearer_ip_family_to_mbim_context_ip_type    (MMBearerIpFamily      ip_family,
                                                                     GError              **error);
+gchar              *mm_mbim_context_ip_type_get_printable          (MbimContextIpType     ip_type);
 MMBearerApnType     mm_bearer_apn_type_from_mbim_context_type      (MbimContextType       context_type);
 MbimContextType     mm_bearer_apn_type_to_mbim_context_type        (MMBearerApnType       apn_type,
                                                                     gboolean              mbim_extensions_supported,