output: handle outputs that are enabled but not yet added

output_config_apply() currently assumes that any enabled outputs have
already been added to the wlr_output_layout. However, at startup,
wlroots will report that outputs are enabled if they were previously in
use by e.g. the Linux console - but they are not yet in the layout.

output_config_apply() never encountered this case before now because the
initial modeset was performed by another code path, but now with the new
autoEnableOutputs option (next commit), it needs to be able to handle
the initial modeset as well.

diff --git a/src/output.c b/src/output.c
index 821b5094aff58e04b005ff637e042f65926a0114..a75f6e13a8c5810a7021942cbc28534265accb69 100644 (file)
--- a/src/output.c
+++ b/src/output.c
@@ -565,8 +565,6 @@ output_config_apply(struct server *server,
                struct output *output = output_from_wlr_output(server, o);
                struct wlr_output_state *os = &output->pending;
                bool output_enabled = head->state.enabled && !output->leased;
-               bool need_to_add = output_enabled && !o->enabled;
-               bool need_to_remove = !output_enabled && o->enabled;
 
                wlr_output_state_set_enabled(os, output_enabled);
                if (output_enabled) {
@@ -601,12 +599,19 @@ output_config_apply(struct server *server,
                        break;
                }
 
-               /* Only do Layout specific actions if the commit went trough */
-               if (need_to_add) {
-                       add_output_to_layout(server, output);
-               }
+               /*
+                * Add or remove output from layout only if the commit went
+                * through. Note that at startup, the output may have already
+                * been enabled but not yet been added to the layout.
+                */
+               bool was_in_layout =
+                       !!wlr_output_layout_get(server->output_layout, o);
 
                if (output_enabled) {
+                       if (!was_in_layout) {
+                               add_output_to_layout(server, output);
+                       }
+
                        struct wlr_box pos = {0};
                        wlr_output_layout_get_box(server->output_layout, o, &pos);
                        if (pos.x != head->state.x || pos.y != head->state.y) {
@@ -618,9 +623,7 @@ output_config_apply(struct server *server,
                                wlr_output_layout_add(server->output_layout, o,
                                        head->state.x, head->state.y);
                        }
-               }
-
-               if (need_to_remove) {
+               } else if (was_in_layout) {
                        regions_evacuate_output(output);
 
                        lab_cosmic_workspace_group_output_leave(