IFP: Return a specific value on failure connecting to the system bus

We need to treat the failure to connect to the system bus as non-fatal.
In this commit, we introduce a special error code and only print a DEBUG
message when this error code is returned from the startup function.

Reviewed-by: Pavel Březina <pbrezina@redhat.com>

3 files changed, 8 insertions, 2 deletions

diff --git a/src/responder/ifp/ifpsrv.c b/src/responder/ifp/ifpsrv.c
index 5dc5652b6..9014c3e85 100644
--- a/src/responder/ifp/ifpsrv.c
+++ b/src/responder/ifp/ifpsrv.c
@@ -192,7 +192,7 @@ sysbus_init(TALLOC_CTX *mem_ctx,
         DEBUG(SSSDBG_CRIT_FAILURE,
               "Failed to connect to D-BUS system bus: [%s]\n",
               dbus_error.message);
-        ret = EIO;
+        ret = ERR_NO_SYSBUS;
         goto fail;
     }
     dbus_connection_set_exit_on_disconnect(conn, FALSE);
@@ -372,7 +372,11 @@ int ifp_process_init(TALLOC_CTX *mem_ctx,
                       INFOPIPE_IFACE,
                       ifp_ifaces,
                       ifp_ctx, &ifp_ctx->sysbus);
-    if (ret != EOK) {
+    if (ret == ERR_NO_SYSBUS) {
+        DEBUG(SSSDBG_MINOR_FAILURE,
+              "The system bus is not available..\n");
+        /* Explicitly ignore, the D-Bus daemon will start us */
+    } else if (ret != EOK) {
         DEBUG(SSSDBG_CRIT_FAILURE,
               "Failed to connect to the system message bus\n");
         talloc_free(ifp_ctx);
diff --git a/src/util/util_errors.c b/src/util/util_errors.c
index 113567423..aa5693190 100644
--- a/src/util/util_errors.c
+++ b/src/util/util_errors.c
@@ -60,6 +60,7 @@ struct err_string error_to_str[] = {
     { "Bus message has no sender" }, /* ERR_SBUS_NO_SENDER */
     { "User/Group SIDs not found" }, /* ERR_NO_SIDS */
     { "Bus method not supported" }, /* ERR_SBUS_NOSUP */
+    { "Cannot connect to system bus" }, /* ERR_NO_SYSBUS */
 };
 
 
diff --git a/src/util/util_errors.h b/src/util/util_errors.h
index b88c7969b..f68409eed 100644
--- a/src/util/util_errors.h
+++ b/src/util/util_errors.h
@@ -82,6 +82,7 @@ enum sssd_errors {
     ERR_SBUS_NO_SENDER,
     ERR_NO_SIDS,
     ERR_SBUS_NOSUP,
+    ERR_NO_SYSBUS,
     ERR_LAST            /* ALWAYS LAST */
 };