From c1927f0948791464c6b576755436efd60b2aea39 Mon Sep 17 00:00:00 2001
From: lkn <lkn@localhost>
Date: Mon, 22 Jun 2026 00:29:28 +0200
Subject: [PATCH] wayland: defer layer-shell configure to initial commit

wlroots 0.19 asserts that the surface is initialized before
wlr_layer_surface_v1_configure is called. Defer the configure to the
initial commit, matching the pattern used for xdg_toplevel surfaces.
Fixes screenshot tool crash.
---
 src/backend/wayland/wl_layer_shell.c | 58 +++++++++++++++++++---------
 src/backend/wayland/wl_types.h       |  1 +
 2 files changed, 40 insertions(+), 19 deletions(-)

diff --git a/src/backend/wayland/wl_layer_shell.c b/src/backend/wayland/wl_layer_shell.c
index e0131ac..6e8c7e5 100644
--- a/src/backend/wayland/wl_layer_shell.c
+++ b/src/backend/wayland/wl_layer_shell.c
@@ -112,6 +112,8 @@ handle_layer_surface_destroy(struct wl_listener *listener, void *data)
     wl_list_remove(&lv->map_listener.link);
     wl_list_remove(&lv->unmap_listener.link);
     wl_list_remove(&lv->destroy_listener.link);
+    if (lv->commit_listener.link.next)
+        wl_list_remove(&lv->commit_listener.link);
     if (lv->scene_node) {
         wlr_scene_node_destroy(&lv->scene_node->node);
         lv->scene_node = NULL;
@@ -120,6 +122,36 @@ handle_layer_surface_destroy(struct wl_listener *listener, void *data)
     free(lv);
 }
 
+static void
+handle_layer_surface_initial_commit(struct wl_listener *listener, void *data)
+{
+    struct wl_layer_view *lv = wl_container_of(listener, lv, commit_listener);
+    struct wlr_layer_surface_v1 *ls = lv->layer_surface;
+    (void)data;
+
+    if (!ls->initial_commit)
+        return;
+
+    /* Only need this once. */
+    wl_list_remove(&lv->commit_listener.link);
+    wl_list_init(&lv->commit_listener.link);
+
+    uint32_t ow = 1920, oh = 1080;
+    if (ls->output) {
+        ow = ls->output->width  > 0 ? (uint32_t)ls->output->width  : 1920;
+        oh = ls->output->height > 0 ? (uint32_t)ls->output->height : 1080;
+    }
+    uint32_t fw, fh;
+    layer_surface_compute_geometry(ls, ow, oh, &fw, &fh);
+    wlr_layer_surface_v1_configure(ls, fw, fh);
+
+    if (lv->scene_node) {
+        int sx, sy;
+        layer_surface_compute_position(ls, ow, oh, fw, fh, &sx, &sy);
+        wlr_scene_node_set_position(&lv->scene_node->node, sx, sy);
+    }
+}
+
 /*
  * handle_layer_shell_new_surface — a client created a layer surface.
  * Assign the output if unset, compute geometry, send configure, and
@@ -162,23 +194,6 @@ handle_layer_shell_new_surface(struct wl_listener *listener, void *data)
         lv->scene_node = wlr_scene_subsurface_tree_create(_lp, ls->surface);
     }
 
-    /* Compute and send initial configure. */
-    uint32_t ow = 1920, oh = 1080;
-    if (ls->output) {
-        ow = ls->output->width  > 0 ? (uint32_t)ls->output->width  : 1920;
-        oh = ls->output->height > 0 ? (uint32_t)ls->output->height : 1080;
-    }
-    uint32_t fw, fh;
-    layer_surface_compute_geometry(ls, ow, oh, &fw, &fh);
-    wlr_layer_surface_v1_configure(ls, fw, fh);
-
-    /* Position the scene node. */
-    if (lv->scene_node) {
-        int sx, sy;
-        layer_surface_compute_position(ls, ow, oh, fw, fh, &sx, &sy);
-        wlr_scene_node_set_position(&lv->scene_node->node, sx, sy);
-    }
-
     /* Wire lifecycle listeners. */
     lv->map_listener.notify     = handle_layer_surface_map;
     lv->unmap_listener.notify   = handle_layer_surface_unmap;
@@ -187,10 +202,15 @@ handle_layer_shell_new_surface(struct wl_listener *listener, void *data)
     wl_signal_add(&ls->surface->events.unmap, &lv->unmap_listener);
     wl_signal_add(&ls->events.destroy,         &lv->destroy_listener);
 
+    /* Defer configure until the surface's initial commit (wlroots 0.19
+     * requires the surface to be initialized before configure). */
+    lv->commit_listener.notify = handle_layer_surface_initial_commit;
+    wl_signal_add(&ls->surface->events.commit, &lv->commit_listener);
+
     wl_list_insert(&wl_state.layer_list, &lv->link);
 
-    wwarning("wl_backend: layer surface new layer=%d %ux%u namespace=%s",
-             ls->current.layer, fw, fh,
+    wwarning("wl_backend: layer surface new layer=%d namespace=%s",
+             ls->pending.layer,
              ls->namespace ? ls->namespace : "");
 }
 
diff --git a/src/backend/wayland/wl_types.h b/src/backend/wayland/wl_types.h
index f670dd1..657230d 100644
--- a/src/backend/wayland/wl_types.h
+++ b/src/backend/wayland/wl_types.h
@@ -122,6 +122,7 @@ struct wl_layer_view {
     struct wl_listener           map_listener;
     struct wl_listener           unmap_listener;
     struct wl_listener           destroy_listener;
+    struct wl_listener           commit_listener;
     struct wl_list               link;    /* wl_state.layer_list */
 };