🐛 Fix wasm context restore guards (#10824)

* 🐛 Prevent WASM panics during WebGL context restore Delay context-restored until reload finishes and no-op app mutations while reloading so resize/modifiers cannot panic mid-teardown. * 🐛 Fall back to CLJS bool content when WASM is not ready Returning nil from calculate-bool would persist empty path content during context loss/reload; use path/calc-bool-content instead.
2026-07-31 18:36:18 +00:00 · 2026-07-29 10:06:52 +02:00 · 2026-07-29 10:06:52 +02:00 · 4cd34b22e2
commit 4cd34b22e2
parent e14e7bb616
10 changed files with 540 additions and 413 deletions
--- a/frontend/src/app/main/data/changes.cljs
+++ b/frontend/src/app/main/data/changes.cljs
@ -20,7 +20,6 @@
   [app.main.worker :as mw]
   [app.render-wasm.api :as wasm.api]
   [app.render-wasm.shape :as wasm.shape]
-   [app.render-wasm.wasm :as wasm]
   [beicon.v2.core :as rx]
   [potok.v2.core :as ptk]))

@ -90,8 +89,7 @@
  (ptk/reify ::sync-wasm-structural-changes
    ptk/EffectEvent
    (effect [_ state _]
-      (when (and wasm/context-initialized?
-                 (not @wasm/context-lost?))
+      (when (wasm.api/initialized?)
        (let [objects (dsh/lookup-page-objects state)
              shapes
              (into []
--- a/frontend/src/app/main/data/workspace.cljs
+++ b/frontend/src/app/main/data/workspace.cljs
@ -355,8 +355,7 @@
            features     (features/get-enabled-features state team-id)
            render-wasm-enabled? (features/active-feature? state "render-wasm/v1")
            render-wasm-ready?   #(and render-wasm-enabled?
-                                       wasm-state/context-initialized?
-                                       (not @wasm-state/context-lost?))]
+                                       (wasm-state/ready?))]

        (log/debug :hint "initialize-workspace"
                   :team-id (dm/str team-id)
--- a/frontend/src/app/main/data/workspace/modifiers.cljs
+++ b/frontend/src/app/main/data/workspace/modifiers.cljs
@ -683,7 +683,7 @@
        ty (.-f first-matrix)]
    (if-let [base @cache]
      (translate-selrect base tx ty)
-      (let [computed (wasm.api/get-selection-rect ids)]
+      (when-let [computed (wasm.api/get-selection-rect ids)]
        (vreset! cache (translate-selrect computed (- tx) (- ty)))
        computed))))

@ -729,15 +729,27 @@
            (vreset! wasm-structure-modifiers-active? true)))
        (let [geometry-entries (parse-geometry-modifiers modif-tree)
              root-modifiers   (into [] (map (fn [[id data]] [id (:transform data)])) geometry-entries)
+              wasm-ready?      (wasm.api/initialized?)
+              ;; While the GL context is down (lost / mid-reload), keep the
+              ;; root transforms so SVG selection/preview can still move.
+              ;; `propagate-modifiers` returns [] when not ready, do not
+              ;; treat that as "no modifiers".
              modifiers
-              (if (and translation? (not snap-pixel?))
+              (cond
+                (or (not wasm-ready?)
+                    (and translation? (not snap-pixel?)))
                root-modifiers
-                (wasm.api/propagate-modifiers geometry-entries snap-pixel?))]
-          (wasm.api/set-modifiers modifiers)
+
+                :else
+                (let [propagated (wasm.api/propagate-modifiers geometry-entries snap-pixel?)]
+                  (if (seq propagated) propagated root-modifiers)))]
+          (when wasm-ready?
+            (wasm.api/set-modifiers modifiers))
          (let [ids     (into [] xf:map-key geometry-entries)
-                selrect (if (and translation? (not snap-pixel?) selection-rect-cache (seq modifiers))
-                          (cached-translation-selrect ids (second (first modifiers)) selection-rect-cache)
-                          (wasm.api/get-selection-rect ids))]
+                selrect (when wasm-ready?
+                          (if (and translation? (not snap-pixel?) selection-rect-cache (seq modifiers))
+                            (cached-translation-selrect ids (second (first modifiers)) selection-rect-cache)
+                            (wasm.api/get-selection-rect ids)))]
            (rx/of (set-temporary-selrect selrect)
                   (set-temporary-modifiers modifiers))))))))

@ -795,7 +807,8 @@
              (and (not ignore-snap-pixel) (contains? (:workspace-layout state) :snap-pixel-grid))

              transforms
-              (if (and translation? (not snap-pixel?))
+              (cond
+                (and translation? (not snap-pixel?))
                ;; Mirror WASM `propagate_modifiers` in CLJS: splat the
                ;; translation matrix onto every descendant. Without
                ;; this step the commit would only touch the dragged
@ -815,6 +828,26 @@
                     (reduce (fn [a sid] (assoc a sid t)) acc subtree-ids)))
                 {}
                 geometry-entries)
+
+                ;; Context lost / mid-reload: do not call into WASM. Use
+                ;; root transforms (and splat translation onto descendants
+                ;; when we can) so the commit still lands in file data.
+                (not (wasm.api/initialized?))
+                (if translation?
+                  (reduce
+                   (fn [acc [id data]]
+                     (let [t (:transform data)
+                           subtree-ids
+                           (or (get subtree-ids-by-id id)
+                               (cfh/get-children-ids-with-self objects id))]
+                       (reduce (fn [a sid] (assoc a sid t)) acc subtree-ids)))
+                   {}
+                   geometry-entries)
+                  (into {}
+                        (map (fn [[id data]] [id (:transform data)]))
+                        geometry-entries))
+
+                :else
                (into {} (wasm.api/propagate-modifiers geometry-entries snap-pixel?)))

              ignore-tree
--- a/frontend/src/app/render_wasm/api.cljs
+++ b/frontend/src/app/render_wasm/api.cljs
--- a/frontend/src/app/render_wasm/api/fonts.cljs
+++ b/frontend/src/app/render_wasm/api/fonts.cljs
@ -119,7 +119,7 @@

 (defn update-text-layout
  [id]
-  (when wasm/context-initialized?
+  (when (wasm/live?)
    (let [shape-id-buffer (uuid/get-u32 id)]
      (h/call wasm/internal-module "_update_shape_text_layout_for"
              (aget shape-id-buffer 0)
@ -129,7 +129,7 @@

 (defn force-update-text-layout
  [id]
-  (when wasm/context-initialized?
+  (when (wasm/live?)
    (let [shape-id-buffer (uuid/get-u32 id)]
      (h/call wasm/internal-module "_force_update_shape_text_layout_for"
              (aget shape-id-buffer 0)
@ -140,7 +140,7 @@
 ;; IMPORTANT: Only TTF fonts can be stored.
 (defn- store-font-buffer
  [font-data font-array-buffer emoji? fallback?]
-  (when wasm/context-initialized?
+  (when (wasm/live?)
    (let [font-id-buffer  (:family-id-buffer font-data)
          size (.-byteLength font-array-buffer)
          ptr  (h/call wasm/internal-module "_alloc_bytes" size)
--- a/frontend/src/app/render_wasm/api/shapes.cljs
+++ b/frontend/src/app/render_wasm/api/shapes.cljs
@ -94,7 +94,7 @@

   Returns nil."
  [shape]
-  (when wasm/context-initialized?
+  (when (wasm/live?)
    (let [id           (dm/get-prop shape :id)
          parent-id    (get shape :parent-id)
          shape-type   (dm/get-prop shape :type)
--- a/frontend/src/app/render_wasm/api/webgl.cljs
+++ b/frontend/src/app/render_wasm/api/webgl.cljs
@ -14,7 +14,7 @@
 (defn get-webgl-context
  "Gets the WebGL context from the WASM module"
  []
-  (when wasm/context-initialized?
+  (when (wasm/live?)
    (let [gl-obj (unchecked-get wasm/internal-module "GL")]
      (when gl-obj
        ;; Get the current WebGL context from Emscripten
--- a/frontend/src/app/render_wasm/shape.cljs
+++ b/frontend/src/app/render_wasm/shape.cljs
@ -15,7 +15,6 @@
   [app.main.refs :as refs]
   [app.render-wasm.api :as api]
   [app.render-wasm.svg-filters :as svg-filters]
-   [app.render-wasm.wasm :as wasm]
   [beicon.v2.core :as rx]
   [cljs.core :as c]
   [cuerdas.core :as str]))
@ -129,7 +128,7 @@
 ;; The `set-wasm-attr!` can return a list of callbacks to be executed in a second pass.
 (defn- set-wasm-attr!
  [shape k]
-  (when wasm/context-initialized?
+  (when (api/initialized?)
    (let [shape (case k
                  :svg-attrs (svg-filters/apply-svg-derived (assoc shape :svg-attrs (get shape :svg-attrs)))
                  (:fills :blur :shadow) (svg-filters/apply-svg-derived shape)
@ -334,14 +333,15 @@

 (defn process-shape-changes!
  [objects shape-changes]
-  (let [shape-changes
-        (->> shape-changes
-             ;; We don't need to update the model for shapes not in the current page
-             (filter (fn [[shape-id _]] (shape-in-current-page? shape-id))))]
-    (when (d/not-empty? shape-changes)
-      (->> (rx/from shape-changes)
-           (rx/mapcat (fn [[shape-id props]] (process-shape! (get objects shape-id) props)))
-           (rx/subs! #(api/request-render "set-wasm-attrs"))))))
+  (when (api/initialized?)
+    (let [shape-changes
+          (->> shape-changes
+               ;; We don't need to update the model for shapes not in the current page
+               (filter (fn [[shape-id _]] (shape-in-current-page? shape-id))))]
+      (when (d/not-empty? shape-changes)
+        (->> (rx/from shape-changes)
+             (rx/mapcat (fn [[shape-id props]] (process-shape! (get objects shape-id) props)))
+             (rx/subs! #(api/request-render "set-wasm-attrs")))))))

 ;; `conj` empty set initialization
 (def conj* (fnil conj (d/ordered-set)))
--- a/frontend/src/app/render_wasm/text_editor.cljs
+++ b/frontend/src/app/render_wasm/text_editor.cljs
@ -190,7 +190,7 @@

 (defn text-editor-focus
  [id]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [buffer (uuid/get-u32 id)]
      (when-not (h/call wasm/internal-module "_text_editor_focus"
                        (aget buffer 0)
@ -202,44 +202,44 @@
 (defn text-editor-set-cursor-from-offset
  "Sets caret position from shape relative coordinates"
  [{:keys [x y]}]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_set_cursor_from_offset" x y)))

 (defn text-editor-set-cursor-from-point
  "Sets caret position from screen (canvas) coordinates"
  [{:keys [x y]}]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_set_cursor_from_point" x y)))

 (defn text-editor-toggle-overtype-mode
  "Toggles overtype mode"
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_toggle_overtype_mode")))

 (defn text-editor-pointer-down
  [{:keys [x y]}]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_pointer_down" x y)))

 (defn text-editor-pointer-move
  [{:keys [x y]}]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_pointer_move" x y)))

 (defn text-editor-pointer-up
  [{:keys [x y]}]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_pointer_up" x y)))

 (defn text-editor-update-blink
  [timestamp-ms]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_update_blink" timestamp-ms)))

 (defn text-editor-render-overlay
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_render_overlay")))

 (defn text-editor-render-caret
@ -252,7 +252,7 @@

 (defn text-editor-poll-event
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [res (h/call wasm/internal-module "_text_editor_poll_event")]
      res)))

@ -323,7 +323,7 @@

 (defn text-editor-get-current-styles
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [ptr (h/call wasm/internal-module "_text_editor_get_current_styles")]
      (when (and ptr (not (zero? ptr)))
        (let [heap-u8 (mem/get-heap-u8)
@ -411,7 +411,7 @@
 (defn text-editor-encode-text-pre
  [text]
  (when (and (not (empty? text))
-             wasm/context-initialized?)
+             (wasm/ready?))
    (let [encoder (js/TextEncoder.)
          buf (.encode encoder text)
          heapu8 (mem/get-heap-u8)
@ -422,31 +422,31 @@
 (defn text-editor-encode-text-post
  [text]
  (when (and (not (empty? text))
-             wasm/context-initialized?)
+             (wasm/ready?))
    (mem/free)))

 (defn text-editor-composition-start
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_composition_start")))

 (defn text-editor-composition-update
  [text]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (text-editor-encode-text-pre text)
    (h/call wasm/internal-module "_text_editor_composition_update")
    (text-editor-encode-text-post text)))

 (defn text-editor-composition-end
  [text]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (text-editor-encode-text-pre text)
    (h/call wasm/internal-module "_text_editor_composition_end")
    (text-editor-encode-text-post text)))

 (defn text-editor-insert-text
  [text]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (text-editor-encode-text-pre text)
    (h/call wasm/internal-module "_text_editor_insert_text")
    (text-editor-encode-text-post text)))
@ -455,62 +455,62 @@
  ([]
   (text-editor-delete-backward false))
  ([word-boundary]
-   (when wasm/context-initialized?
+   (when (wasm/ready?)
     (h/call wasm/internal-module "_text_editor_delete_backward" word-boundary))))

 (defn text-editor-delete-forward
  ([]
   (text-editor-delete-forward false))
  ([word-boundary]
-   (when wasm/context-initialized?
+   (when (wasm/ready?)
     (h/call wasm/internal-module "_text_editor_delete_forward" word-boundary))))

 (defn text-editor-insert-paragraph []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_insert_paragraph")))

 (defn text-editor-move-cursor
  [direction word-boundary extend-selection]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_move_cursor" direction word-boundary (if extend-selection 1 0))))

 (defn text-editor-select-all
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_select_all")))

 (defn text-editor-select-word-boundary
  [{:keys [x y]}]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_select_word_boundary" x y)))

 (defn text-editor-blur
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (when-not (h/call wasm/internal-module "_text_editor_blur")
      (throw (js/Error. "TextEditor blur failed")))))

 (defn text-editor-dispose
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (h/call wasm/internal-module "_text_editor_dispose")))

 (defn text-editor-has-focus?
  ([id]
-   (when wasm/context-initialized?
+   (when (wasm/ready?)
     (not (zero? (h/call wasm/internal-module "_text_editor_has_focus_with_id" id)))))
  ([]
-   (when wasm/context-initialized?
+   (when (wasm/ready?)
     (not (zero? (h/call wasm/internal-module "_text_editor_has_focus"))))))

 (defn text-editor-has-selection?
  ([]
-   (when wasm/context-initialized?
+   (when (wasm/ready?)
     (not (zero? (h/call wasm/internal-module "_text_editor_has_selection"))))))

 (defn text-editor-export-content
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [ptr (h/call wasm/internal-module "_text_editor_export_content")]
      (when (and ptr (not (zero? ptr)))
        (let [json-str (mem/read-string ptr)]
@ -520,7 +520,7 @@
 (defn text-editor-export-selection
  "Export only the currently selected text as plain text from the WASM editor. Requires WASM support (_text_editor_export_selection)."
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [ptr (h/call wasm/internal-module "_text_editor_export_selection")]
      (when (and ptr (not (zero? ptr)))
        (let [text (mem/read-string ptr)]
@ -529,7 +529,7 @@

 (defn text-editor-get-active-shape-id
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (try
      (let [byte-offset (mem/alloc 16)
            u32-offset (mem/->offset-32 byte-offset)
@ -549,7 +549,7 @@

 (defn text-editor-get-selection
  []
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [byte-offset     (mem/alloc 16)
          u32-offset      (mem/->offset-32 byte-offset)
          heap            (mem/get-heap-u32)
@ -643,7 +643,7 @@
  shape-id and the fully merged content map ready for
  v2-update-text-shape-content."
  []
-  (when (and wasm/context-initialized? (text-editor-has-focus?))
+  (when (and (wasm/ready?) (text-editor-has-focus?))
    (let [shape-id  (text-editor-get-active-shape-id)
          new-texts (text-editor-export-content)]
      (when (and shape-id new-texts)
@ -707,7 +707,7 @@

 (defn apply-styles-to-selection
  [attrs use-shape-fn set-shape-text-content-fn]
-  (when wasm/context-initialized?
+  (when (wasm/ready?)
    (let [shape-id  (text-editor-get-active-shape-id)
          selection (text-editor-get-selection)]

--- a/frontend/src/app/render_wasm/wasm.cljs
+++ b/frontend/src/app/render_wasm/wasm.cljs
@ -28,6 +28,11 @@
 (defonce context-initialized? false)
 (defonce context-lost? (atom false))

+;; True while `reload-renderer!` is reconstructing the GL/WASM pipeline after a
+;; WebGL context restore (or an explicit reload). External app callers must not
+;; touch WASM until this clears (`ready?`); reload-internal ops use `live?`.
+(defonce reloading? (atom false))
+
 ;; When we're rendering in a sync way we want to stop the asynchrous `request-render`
 (defonce disable-request-render? (atom false))

@ -35,15 +40,30 @@
  []
  (and internal-module (fn? (unchecked-get internal-module "_init"))))

+(defn live?
+  "GL/WASM context exists and is not marked lost. True during reload after re-init."
+  []
+  (and context-initialized? (not @context-lost?)))
+
+(defn ready?
+  "Safe for normal application WASM calls (not lost, not mid-reload)."
+  []
+  (and (live?) (not @reloading?)))
+
 (defn reset-context-state!
+  "Clears canvas/GL handles and marks the context uninitialized.
+
+  Intentionally does **not** clear `context-lost?` or `reloading?`. During a
+  context-restore reload, `clear-canvas` runs while recovery is still in
+  progress; clearing those flags here would reopen a window where callers think
+  WebGL is ready before re-init finishes."
  []
  (set! internal-frame-id nil)
  (set! canvas nil)
  (set! canvas-snapshot nil)
  (set! gl-context-handle nil)
  (set! gl-context nil)
-  (set! context-initialized? false)
-  (reset! context-lost? false))
+  (set! context-initialized? false))

 (defonce serializers
  #js {:raster-format shared/RasterFormat