From 7f44e54ad6b898923f3b602e311c3dac404533ad Mon Sep 17 00:00:00 2001
From: Idan Horowitz <idan.horowitz@gmail.com>
Date: Tue, 15 Feb 2022 20:55:53 +0200
Subject: [PATCH] AK+Kernel: Return KString from UUID::to_string() in the
 Kernel

This lets us safely handle allocation failure.
---
 AK/UUID.cpp | 17 +++++++++++++++++
 AK/UUID.h   | 10 ++++++++++
 2 files changed, 27 insertions(+)

diff --git a/AK/UUID.cpp b/AK/UUID.cpp
index ac76da14646..8353c49c1ec 100644
--- a/AK/UUID.cpp
+++ b/AK/UUID.cpp
@@ -76,6 +76,22 @@ UUID::UUID(StringView uuid_string_view, Endianness endianness)
     VERIFY_NOT_REACHED();
 }
 
+#ifdef KERNEL
+ErrorOr<NonnullOwnPtr<Kernel::KString>> UUID::to_string() const
+{
+    StringBuilder builder(36);
+    TRY(builder.try_append(encode_hex(m_uuid_buffer.span().trim(4)).view()));
+    TRY(builder.try_append('-'));
+    TRY(builder.try_append(encode_hex(m_uuid_buffer.span().slice(4).trim(2)).view()));
+    TRY(builder.try_append('-'));
+    TRY(builder.try_append(encode_hex(m_uuid_buffer.span().slice(6).trim(2)).view()));
+    TRY(builder.try_append('-'));
+    TRY(builder.try_append(encode_hex(m_uuid_buffer.span().slice(8).trim(2)).view()));
+    TRY(builder.try_append('-'));
+    TRY(builder.try_append(encode_hex(m_uuid_buffer.span().slice(10).trim(6)).view()));
+    return Kernel::KString::try_create(builder.string_view());
+}
+#else
 String UUID::to_string() const
 {
     StringBuilder builder(36);
@@ -90,6 +106,7 @@ String UUID::to_string() const
     builder.append(encode_hex(m_uuid_buffer.span().slice(10).trim(6)).view());
     return builder.to_string();
 }
+#endif
 
 bool UUID::operator==(const UUID& other) const
 {
diff --git a/AK/UUID.h b/AK/UUID.h
index 066d3010912..c859cf3729d 100644
--- a/AK/UUID.h
+++ b/AK/UUID.h
@@ -11,6 +11,12 @@
 #include <AK/StringView.h>
 #include <AK/Types.h>
 
+#ifdef KERNEL
+#    include <Kernel/KString.h>
+#else
+#    include <AK/String.h>
+#endif
+
 namespace AK {
 
 class UUID {
@@ -32,7 +38,11 @@ public:
     bool operator<(const UUID&) const = delete;
     bool operator>(const UUID&) const = delete;
 
+#ifdef KERNEL
+    ErrorOr<NonnullOwnPtr<Kernel::KString>> to_string() const;
+#else
     String to_string() const;
+#endif
     bool is_zero() const;
 
 private: