Harden NULL handling in update and font paths

README.md

@@ -95,6 +95,9 @@ float GetNuklearScaling(struct nk_context * ctx);            // Retrieves the sc
 
 See the [Nuklear API documenation](https://immediate-mode-ui.github.io/Nuklear/doc/nuklear.html) for more how to use Nuklear.
 
+> [!WARNING]
+> *raylib-nuklear* stores its own state (scaling, insert mode, double-click tracking) in the context's user data. Calling `nk_set_user_data()` replaces it, which disables scaling, insert mode and double-click detection. Save `ctx->userdata` beforehand and restore it before `UnloadNuklear()`.
+
 ## Configuration
 
 The following macros can be defined before including `raylib-nuklear.h` to tune behavior:

include/raylib-nuklear.h

@@ -468,10 +468,19 @@ NK_API Font LoadFontFromNuklear(int size) {
     // Decode base85 -> compressed binary -> raw TTF
     int compressed_size = (((int)nk_strlen(nk_proggy_clean_ttf_compressed_data_base85) + 4) / 5) * 4;
     unsigned char *compressed_data = (unsigned char*)MemAlloc((unsigned int)compressed_size);
+    if (compressed_data == NULL) {
+        TraceLog(LOG_ERROR, "NUKLEAR: Failed to allocate the default font data");
+        return CLITERAL(Font) {0};
+    }
     nk_decode_85(compressed_data, (const unsigned char*)nk_proggy_clean_ttf_compressed_data_base85);
 
     unsigned int ttf_size = nk_decompress_length(compressed_data);
     unsigned char *ttf_data = (unsigned char*)MemAlloc(ttf_size);
+    if (ttf_data == NULL) {
+        TraceLog(LOG_ERROR, "NUKLEAR: Failed to allocate the default font data");
+        MemFree(compressed_data);
+        return CLITERAL(Font) {0};
+    }
     nk_decompress(ttf_data, compressed_data, (unsigned int)compressed_size);
     MemFree(compressed_data);
 
@@ -962,9 +971,11 @@ nk_raylib_input_keyboard(struct nk_context * ctx)
     nk_input_key(ctx, NK_KEY_TAB, IsKeyDown(KEY_TAB));
 
     NuklearUserData* userData = (NuklearUserData*)ctx->userdata.ptr;
-    if (IsKeyPressed(KEY_INSERT)) userData->insert_mode = !userData->insert_mode;
-    nk_input_key(ctx, NK_KEY_TEXT_INSERT_MODE, userData->insert_mode);
-    nk_input_key(ctx, NK_KEY_TEXT_REPLACE_MODE, !userData->insert_mode);
+    if (userData != NULL) {
+        if (IsKeyPressed(KEY_INSERT)) userData->insert_mode = !userData->insert_mode;
+        nk_input_key(ctx, NK_KEY_TEXT_INSERT_MODE, userData->insert_mode);
+        nk_input_key(ctx, NK_KEY_TEXT_REPLACE_MODE, !userData->insert_mode);
+    }
 
     int code;
     while ((code = GetCharPressed()) != 0) {
@@ -1010,15 +1021,17 @@ nk_raylib_input_mouse(struct nk_context * ctx)
     // Double Click
     {
         NuklearUserData* userData = (NuklearUserData*)ctx->userdata.ptr;
-        if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON)) {
-            double now = GetTime();
-            userData->double_clicking = now - userData->last_left_press <= RAYLIB_NUKLEAR_DOUBLE_CLICK_THRESHOLD;
-            userData->last_left_press = now;
-        }
-        else if (IsMouseButtonReleased(MOUSE_LEFT_BUTTON)) {
-            userData->double_clicking = false;
+        if (userData != NULL) {
+            if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON)) {
+                double now = GetTime();
+                userData->double_clicking = now - userData->last_left_press <= RAYLIB_NUKLEAR_DOUBLE_CLICK_THRESHOLD;
+                userData->last_left_press = now;
+            }
+            else if (IsMouseButtonReleased(MOUSE_LEFT_BUTTON)) {
+                userData->double_clicking = false;
+            }
+            nk_input_button(ctx, NK_BUTTON_DOUBLE, mouseX, mouseY, userData->double_clicking);
         }
-        nk_input_button(ctx, NK_BUTTON_DOUBLE, mouseX, mouseY, userData->double_clicking);
     }
 
     // Mouse Wheel
@@ -1049,6 +1062,11 @@ UpdateNuklear(struct nk_context * ctx)
 NK_API void
 UpdateNuklearEx(struct nk_context * ctx, float deltaTime)
 {
+    // Skip updating if it's not set.
+    if (ctx == NULL) {
+        return;
+    }
+
     // Update the time that has changed since last frame.
     ctx->delta_time_seconds = deltaTime;
 

test/raylib-nuklear-test.c

@@ -202,6 +202,38 @@ int main(int argc, char *argv[]) {
         UnloadNuklear(ctx);
     }
 
+    // A NULL context must not crash any of the public entry points.
+    {
+        UpdateNuklear(NULL);
+        UpdateNuklearEx(NULL, 1.0f / 60.0f);
+        DrawNuklear(NULL);
+        SetNuklearScaling(NULL, 2.0f);
+        AssertEqual(GetNuklearScaling(NULL), 1.0f);
+        UnloadNuklear(NULL);
+    }
+
+    // Replacing the context user data with nk_set_user_data() must not crash.
+    {
+        ctx = InitNuklear(10);
+        Assert(ctx);
+
+        nk_handle original = ctx->userdata;
+        nk_set_user_data(ctx, nk_handle_ptr(NULL));
+
+        UpdateNuklear(ctx);
+        UpdateNuklearEx(ctx, 1.0f / 60.0f);
+        AssertEqual(GetNuklearScaling(ctx), 1.0f);
+
+        BeginDrawing();
+            ClearBackground(RAYWHITE);
+            DrawNuklear(ctx);
+        EndDrawing();
+
+        // Restore the internal user data so that it's still freed on unload.
+        nk_set_user_data(ctx, original);
+        UnloadNuklear(ctx);
+    }
+
     // RAYLIB_NUKLEAR_VERSION macros
     Assert(RAYLIB_NUKLEAR_VERSION_MAJOR >= 1);
     Assert(RAYLIB_NUKLEAR_VERSION_MINOR >= 0);