scaled-scene-buffer: guard against negative sizes

src/common/scaled-icon-buffer.c

@@ -79,6 +79,9 @@ struct scaled_icon_buffer *
 scaled_icon_buffer_create(struct wlr_scene_tree *parent, struct server *server,
 	int width, int height)
 {
+	assert(parent);
+	assert(width >= 0 && height >= 0);
+
 	struct scaled_scene_buffer *scaled_buffer = scaled_scene_buffer_create(
 		parent, &impl, /* drop_buffer */ true);
 	struct scaled_icon_buffer *self = znew(*self);

src/common/scaled-img-buffer.c

@@ -49,7 +49,10 @@ struct scaled_img_buffer *
 scaled_img_buffer_create(struct wlr_scene_tree *parent, struct lab_img *img,
 	int width, int height)
 {
+	assert(parent);
 	assert(img);
+	assert(width >= 0 && height >= 0);
+
 	struct scaled_scene_buffer *scaled_buffer = scaled_scene_buffer_create(
 		parent, &impl, /* drop_buffer */ true);
 	struct scaled_img_buffer *self = znew(*self);

src/common/scaled-rect-buffer.c

@@ -95,14 +95,16 @@ struct scaled_rect_buffer *scaled_rect_buffer_create(
 	/* TODO: support rounded corners for menus and OSDs */
 
 	assert(parent);
+	assert(width >= 0 && height >= 0);
+
 	struct scaled_rect_buffer *self = znew(*self);
 	struct scaled_scene_buffer *scaled_buffer = scaled_scene_buffer_create(
 		parent, &impl, /* drop_buffer */ true);
 	scaled_buffer->data = self;
 	self->scaled_buffer = scaled_buffer;
 	self->scene_buffer = scaled_buffer->scene_buffer;
-	self->width = MAX(width, 1);
-	self->height = MAX(height, 1);
+	self->width = width;
+	self->height = height;
 	self->border_width = border_width;
 	memcpy(self->fill_color, fill_color, sizeof(self->fill_color));
 	memcpy(self->border_color, border_color, sizeof(self->border_color));

src/common/scaled-scene-buffer.c

@@ -227,6 +227,9 @@ scaled_scene_buffer_request_update(struct scaled_scene_buffer *self,
 		int width, int height)
 {
 	assert(self);
+	assert(width >= 0);
+	assert(height >= 0);
+
 	struct scaled_scene_buffer_cache_entry *cache_entry, *cache_entry_tmp;
 	wl_list_for_each_safe(cache_entry, cache_entry_tmp, &self->cache, link) {
 		_cache_entry_destroy(cache_entry, self->drop_buffer);