From b90a794d78b3c25764401585ebca3fe84e151dc2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Julian=20Offenh=C3=A4user?= <offenhaeuser@protonmail.com>
Date: Fri, 24 Mar 2023 22:12:31 +0100
Subject: [PATCH] LibPDF: Allow pages with no specified contents

The contents object may be omitted as per spec, which will just leave
the page blank.
---
 Userland/Libraries/LibPDF/Document.cpp | 4 +++-
 Userland/Libraries/LibPDF/Document.h   | 2 +-
 Userland/Libraries/LibPDF/Renderer.cpp | 3 +++
 3 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/Userland/Libraries/LibPDF/Document.cpp b/Userland/Libraries/LibPDF/Document.cpp
index de1a373a95..72340e229c 100644
--- a/Userland/Libraries/LibPDF/Document.cpp
+++ b/Userland/Libraries/LibPDF/Document.cpp
@@ -116,7 +116,9 @@ PDFErrorOr<Page> Document::get_page(u32 index)
     else
         resources = adopt_ref(*new DictObject({}));
 
-    auto contents = TRY(raw_page_object->get_object(this, CommonNames::Contents));
+    RefPtr<Object> contents;
+    if (raw_page_object->contains(CommonNames::Contents))
+        contents = TRY(raw_page_object->get_object(this, CommonNames::Contents));
 
     Rectangle media_box;
     auto maybe_media_box_object = TRY(get_inheritable_object(CommonNames::MediaBox, raw_page_object));
diff --git a/Userland/Libraries/LibPDF/Document.h b/Userland/Libraries/LibPDF/Document.h
index 8880c653a2..787d37a3f2 100644
--- a/Userland/Libraries/LibPDF/Document.h
+++ b/Userland/Libraries/LibPDF/Document.h
@@ -30,7 +30,7 @@ struct Rectangle {
 
 struct Page {
     NonnullRefPtr<DictObject> resources;
-    NonnullRefPtr<Object> contents;
+    RefPtr<Object> contents;
     Rectangle media_box;
     Rectangle crop_box;
     float user_unit;
diff --git a/Userland/Libraries/LibPDF/Renderer.cpp b/Userland/Libraries/LibPDF/Renderer.cpp
index eb1f0681d2..945f93ab4c 100644
--- a/Userland/Libraries/LibPDF/Renderer.cpp
+++ b/Userland/Libraries/LibPDF/Renderer.cpp
@@ -85,6 +85,9 @@ Renderer::Renderer(RefPtr<Document> document, Page const& page, RefPtr<Gfx::Bitm
 
 PDFErrorsOr<void> Renderer::render()
 {
+    if (m_page.contents.is_null())
+        return {};
+
     // Use our own vector, as the /Content can be an array with multiple
     // streams which gets concatenated
     // FIXME: Text operators are supposed to only have effects on the current