From 881fa0b2b0720e0182654a2f0bc79c238e968c30 Mon Sep 17 00:00:00 2001
From: Tomas Tormo <tomas.tormo@nearform.com>
Date: Sun, 12 Nov 2023 22:09:45 +0000
Subject: [PATCH] Add SafePtr wrapper

---
 safeptr.go      | 34 ++++++++++++++++++++++++++++++++++
 safeptr_test.go | 41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+)
 create mode 100644 safeptr.go
 create mode 100644 safeptr_test.go

diff --git a/safeptr.go b/safeptr.go
new file mode 100644
index 00000000..bbe24c2e
--- /dev/null
+++ b/safeptr.go
@@ -0,0 +1,34 @@
+//go:build go1.18
+// +build go1.18
+
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package klog
+
+// SafePtr is a function that takes a pointer of any type (T) as an argument.
+// If the provided pointer is not nil, it returns the same pointer. If it is nil, it returns nil instead.
+//
+// This function is particularly useful to prevent nil pointer dereferencing when:
+//
+//   - The type implements interfaces that are called by the logger, such as `fmt.Stringer`.
+//   - And these interface implementations do not perform nil checks themselves.
+func SafePtr[T any](p *T) any {
+	if p == nil {
+		return nil
+	}
+	return p
+}
diff --git a/safeptr_test.go b/safeptr_test.go
new file mode 100644
index 00000000..4c38b9d8
--- /dev/null
+++ b/safeptr_test.go
@@ -0,0 +1,41 @@
+//go:build go1.18
+// +build go1.18
+
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package klog_test
+
+import (
+	"testing"
+
+	"k8s.io/klog/v2"
+)
+
+func TestSafePtr(t *testing.T) {
+	// Test with nil pointer
+	var stringPtr *string
+	if result := klog.SafePtr(stringPtr); result != nil {
+		t.Errorf("Expected nil, got %p", result)
+	}
+
+	// Test with non-nil pointer
+	expected := "foo"
+	stringPtr = &expected
+	if result := klog.SafePtr(stringPtr); result != stringPtr {
+		t.Errorf("Expected %v, got %v", stringPtr, result)
+	}
+}