From b0fef03e3f24a1c9ca3028f313a23bb1988081b6 Mon Sep 17 00:00:00 2001
From: Brian Gianforcaro <bgianf@serenityos.org>
Date: Wed, 12 May 2021 20:35:08 -0700
Subject: [PATCH] AK: Introduce adopt_own_if_nonnull(..) to aid in Kernel OOM
 hardening

Unfortunately adopt_own requires a reference, which obviously does not
work well with when attempting to harden against allocation failure.
The adopt_own_if_nonnull() variant will allow you to avoid using bare
pointers, while still allowing you to handle allocation failure.
---
 AK/OwnPtr.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/AK/OwnPtr.h b/AK/OwnPtr.h
index 416af312e2..e6d62c6507 100644
--- a/AK/OwnPtr.h
+++ b/AK/OwnPtr.h
@@ -191,6 +191,14 @@ inline void swap(OwnPtr<T>& a, OwnPtr<U>& b)
     a.swap(b);
 }
 
+template<typename T>
+inline OwnPtr<T> adopt_own_if_nonnull(T* object)
+{
+    if (object)
+        return OwnPtr<T>(object);
+    return {};
+}
+
 template<typename T>
 struct Traits<OwnPtr<T>> : public GenericTraits<OwnPtr<T>> {
     using PeekType = T*;
@@ -201,4 +209,5 @@ struct Traits<OwnPtr<T>> : public GenericTraits<OwnPtr<T>> {
 
 }
 
+using AK::adopt_own_if_nonnull;
 using AK::OwnPtr;