From 9038bc675fa43ff9acb4aadcdca2dd181e7d712d Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sat, 12 Jun 2021 10:24:04 +0200
Subject: [PATCH] PixelPaint: Guarantee that constructed Layer always has a
 Gfx::Bitmap

Hoist any allocation failures so that layer factories never return a
bitmap-less layer.
---
 Userland/Applications/PixelPaint/Layer.cpp | 29 ++++++++++------------
 Userland/Applications/PixelPaint/Layer.h   |  7 +++---
 2 files changed, 16 insertions(+), 20 deletions(-)

diff --git a/Userland/Applications/PixelPaint/Layer.cpp b/Userland/Applications/PixelPaint/Layer.cpp
index 5c1125c3bb..c2c47c226d 100644
--- a/Userland/Applications/PixelPaint/Layer.cpp
+++ b/Userland/Applications/PixelPaint/Layer.cpp
@@ -18,15 +18,19 @@ RefPtr<Layer> Layer::try_create_with_size(Image& image, Gfx::IntSize const& size
     if (size.width() > 16384 || size.height() > 16384)
         return nullptr;
 
-    return adopt_ref(*new Layer(image, size, move(name)));
-}
-
-RefPtr<Layer> Layer::try_create_with_bitmap(Image& image, Gfx::Bitmap const& bitmap, String name)
-{
-    if (bitmap.size().is_empty())
+    auto bitmap = Gfx::Bitmap::create(Gfx::BitmapFormat::BGRA8888, size);
+    if (!bitmap)
         return nullptr;
 
-    if (bitmap.size().width() > 16384 || bitmap.size().height() > 16384)
+    return adopt_ref(*new Layer(image, *bitmap, move(name)));
+}
+
+RefPtr<Layer> Layer::try_create_with_bitmap(Image& image, NonnullRefPtr<Gfx::Bitmap> bitmap, String name)
+{
+    if (bitmap->size().is_empty())
+        return nullptr;
+
+    if (bitmap->size().width() > 16384 || bitmap->size().height() > 16384)
         return nullptr;
 
     return adopt_ref(*new Layer(image, bitmap, move(name)));
@@ -49,17 +53,10 @@ RefPtr<Layer> Layer::try_create_snapshot(Image& image, Layer const& layer)
     return snapshot;
 }
 
-Layer::Layer(Image& image, Gfx::IntSize const& size, String name)
+Layer::Layer(Image& image, NonnullRefPtr<Gfx::Bitmap> bitmap, String name)
     : m_image(image)
     , m_name(move(name))
-{
-    m_bitmap = Gfx::Bitmap::create(Gfx::BitmapFormat::BGRA8888, size);
-}
-
-Layer::Layer(Image& image, Gfx::Bitmap const& bitmap, String name)
-    : m_image(image)
-    , m_name(move(name))
-    , m_bitmap(bitmap)
+    , m_bitmap(move(bitmap))
 {
 }
 
diff --git a/Userland/Applications/PixelPaint/Layer.h b/Userland/Applications/PixelPaint/Layer.h
index 846aab6ee5..c6b52e252e 100644
--- a/Userland/Applications/PixelPaint/Layer.h
+++ b/Userland/Applications/PixelPaint/Layer.h
@@ -25,7 +25,7 @@ class Layer
 
 public:
     static RefPtr<Layer> try_create_with_size(Image&, Gfx::IntSize const&, String name);
-    static RefPtr<Layer> try_create_with_bitmap(Image&, Gfx::Bitmap const&, String name);
+    static RefPtr<Layer> try_create_with_bitmap(Image&, NonnullRefPtr<Gfx::Bitmap>, String name);
     static RefPtr<Layer> try_create_snapshot(Image&, Layer const&);
 
     ~Layer() { }
@@ -57,14 +57,13 @@ public:
     void set_opacity_percent(int);
 
 private:
-    Layer(Image&, Gfx::IntSize const&, String name);
-    Layer(Image&, Gfx::Bitmap const&, String name);
+    Layer(Image&, NonnullRefPtr<Gfx::Bitmap>, String name);
 
     Image& m_image;
 
     String m_name;
     Gfx::IntPoint m_location;
-    RefPtr<Gfx::Bitmap> m_bitmap;
+    NonnullRefPtr<Gfx::Bitmap> m_bitmap;
 
     bool m_selected { false };
     bool m_visible { true };