From 1317eea0559311db508c43430f22a6c328f5f615 Mon Sep 17 00:00:00 2001
From: Oliver Hamlet <git@ortham.net>
Date: Mon, 5 May 2025 11:45:50 +0100
Subject: [PATCH] Use Rust Filename comparisons for C++ Filename operators

To prevent inconsistencies between implementations. This means allocating new boxed Filenames for each comparison, but an extra string copy is avoided by making the C++ operators friends of the C++ class (which is ABI-safe).
---
 Cargo.lock                           |  1 -
 cpp/Cargo.toml                       |  1 -
 cpp/include/loot/metadata/filename.h |  4 ++++
 cpp/src/api/metadata/filename.cpp    |  6 ++++--
 cpp/src/lib.rs                       | 23 ++++++++++++-----------
 cpp/src/metadata.rs                  |  2 +-
 6 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 697c9934..163ae5f6 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -573,7 +573,6 @@ dependencies = [
  "delegate",
  "libloot",
  "libloot-ffi-errors",
- "unicase",
 ]
 
 [[package]]
diff --git a/cpp/Cargo.toml b/cpp/Cargo.toml
index c22adf5d..827ad2ee 100644
--- a/cpp/Cargo.toml
+++ b/cpp/Cargo.toml
@@ -9,7 +9,6 @@ cxx = { version = "1.0", features = ["c++17"] }
 delegate = "0.13.2"
 libloot = { path = ".." }
 libloot-ffi-errors = { path = "../ffi-errors" }
-unicase = "2.8.1"
 
 [build-dependencies]
 cxx-build = "1.0"
diff --git a/cpp/include/loot/metadata/filename.h b/cpp/include/loot/metadata/filename.h
index 3c7fc9c9..81584fb5 100644
--- a/cpp/include/loot/metadata/filename.h
+++ b/cpp/include/loot/metadata/filename.h
@@ -54,6 +54,10 @@ public:
 
 private:
   std::string filename_;
+
+  LOOT_API friend bool operator==(const Filename& lhs, const Filename& rhs);
+
+  LOOT_API friend bool operator<(const Filename& lhs, const Filename& rhs);
 };
 
 /**
diff --git a/cpp/src/api/metadata/filename.cpp b/cpp/src/api/metadata/filename.cpp
index 9d24d90e..e05c2b8e 100644
--- a/cpp/src/api/metadata/filename.cpp
+++ b/cpp/src/api/metadata/filename.cpp
@@ -35,7 +35,8 @@ Filename::Filename(std::string_view filename) : filename_(filename) {}
 Filename::operator std::string() const { return filename_; }
 
 bool operator==(const Filename& lhs, const Filename& rhs) {
-  return loot::rust::compare_filenames(std::string(lhs), std::string(rhs)) == 0;
+  return loot::rust::new_filename(lhs.filename_)
+      ->eq(*loot::rust::new_filename(rhs.filename_));
 }
 
 bool operator!=(const Filename& lhs, const Filename& rhs) {
@@ -43,7 +44,8 @@ bool operator!=(const Filename& lhs, const Filename& rhs) {
 }
 
 bool operator<(const Filename& lhs, const Filename& rhs) {
-  return loot::rust::compare_filenames(std::string(lhs), std::string(rhs)) < 0;
+  return loot::rust::new_filename(lhs.filename_)
+             ->lt(*loot::rust::new_filename(rhs.filename_));
 }
 
 bool operator>(const Filename& lhs, const Filename& rhs) { return rhs < lhs; }
diff --git a/cpp/src/lib.rs b/cpp/src/lib.rs
index b1e3f141..6d33bcb4 100644
--- a/cpp/src/lib.rs
+++ b/cpp/src/lib.rs
@@ -119,7 +119,6 @@ use std::{
     ffi::{CString, c_char, c_uchar, c_uint, c_void},
     sync::{Mutex, atomic::AtomicPtr},
 };
-use unicase::UniCase;
 
 use libloot::set_logging_callback;
 pub use libloot::{is_compatible, libloot_revision, libloot_version};
@@ -181,14 +180,6 @@ pub type OptionalPluginMetadata = Optional<PluginMetadata>;
 
 pub type OptionalCrc = Optional<u32>;
 
-fn compare_filenames(lhs: &str, rhs: &str) -> i8 {
-    match UniCase::new(lhs).cmp(&UniCase::new(rhs)) {
-        std::cmp::Ordering::Less => -1,
-        std::cmp::Ordering::Equal => 0,
-        std::cmp::Ordering::Greater => 1,
-    }
-}
-
 fn set_log_level(level: ffi::LogLevel) -> Result<(), VerboseError> {
     libloot::set_log_level(level.try_into()?);
     Ok(())
@@ -295,8 +286,6 @@ mod ffi {
             contents: &[MessageContent],
             language: &str,
         ) -> OptionalMessageContentRef;
-
-        fn compare_filenames(lhs: &str, rhs: &str) -> i8;
     }
 
     extern "Rust" {
@@ -633,6 +622,18 @@ mod ffi {
         pub fn as_str(&self) -> &str;
 
         pub fn boxed_clone(&self) -> Box<Filename>;
+
+        pub fn eq(&self, other: &Filename) -> bool;
+
+        pub fn ne(&self, other: &Filename) -> bool;
+
+        pub fn lt(&self, other: &Filename) -> bool;
+
+        pub fn le(&self, other: &Filename) -> bool;
+
+        pub fn gt(&self, other: &Filename) -> bool;
+
+        pub fn ge(&self, other: &Filename) -> bool;
     }
 
     extern "Rust" {
diff --git a/cpp/src/metadata.rs b/cpp/src/metadata.rs
index 7cbf6085..72c11ad5 100644
--- a/cpp/src/metadata.rs
+++ b/cpp/src/metadata.rs
@@ -446,7 +446,7 @@ impl From<Box<File>> for libloot::metadata::File {
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq, PartialOrd)]
 #[repr(transparent)]
 pub struct Filename(libloot::metadata::Filename);