fc2-systemdetection

A 32-bit drop-in replacement for Far Cry 2's systemdetection.dll. It supports high-core-count systems and applies a small set of validated runtime patches to Dunia.dll.

Features

CPU detection supports systems with 32 or more logical processors.

Runtime patches are resolved inside Portex-parsed PE sections. Every signature-relative destination must be unique and contain either the exact expected game bytes or the exact patched bytes before anything is written.

Patch	Default	Behavior
jackal_tapes	On	Fixes incorrect Southern-map Jackal tape recordings
devmode_always_on	On	Permanently bypasses the developer-command visibility check
predecessor_tapes	On	Unlocks the seven predecessor bonus missions
machetes	On	Unlocks the two bonus machete skins
no_blinking_items	Off	Disables three interactable/objective blinking effects

Steam, Retail/GOG, and Ubisoft Connect 1.03 file layouts are recognized. An unknown build is never patched from an unguarded address: compatible signature-based patches may resolve, while unsupported targets fail closed and are reported.

Installation

1. Download systemdetection.dll from Releases.
2. Back up the existing bin/systemdetection.dll.
3. Copy the downloaded DLL into the game's bin directory.
4. Launch the game.

Common installation locations include:

• Steam: C:\Program Files (x86)\Steam\steamapps\common\Far Cry 2\bin
• GOG: C:\GOG Games\Far Cry 2\bin
• Ubisoft Connect: C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\games\Far Cry 2\bin

Optional configuration

No configuration file is required. To change patch defaults, copy fc2-systemdetection.ini.example beside the DLL and rename it to fc2-systemdetection.ini.

[patches]
jackal_tapes = true
devmode_always_on = true
predecessor_tapes = true
machetes = true
no_blinking_items = false

Values may be true/false, yes/no, on/off, or 1/0. Disabled patches are not scanned.

On initialization, the DLL writes fc2-systemdetection.log beside itself. The log records build detection, configuration warnings, and whether every patch was applied, already applied, disabled, or rejected.

Building

Install rustup, then run the normal Cargo commands from the repository root:

cargo test
cargo build --release

rust-toolchain.toml selects nightly and provisions Clippy, rustfmt, and the 32-bit MSVC standard library. .cargo/config.toml selects i686-pc-windows-msvc as the default build target.

The DLL is written to target/i686-pc-windows-msvc/release/systemdetection.dll.

Development checks

prek manages the repository's commit checks. If you use mise, the checked-in mise.toml tracks the latest Rust and prek releases:

mise install
prek install

Otherwise, install prek using its normal package for your platform, then run prek install. The hook runs rustfmt, Clippy with warnings denied, and the test suite using the repository-selected Rust toolchain. It also checks line endings, whitespace, merge markers, and TOML/YAML syntax. Run the same checks across the worktree on demand with:

prek run --all-files

To validate a legally obtained Dunia.dll without launching the game, point the ignored integration test at it:

$env:FC2_DUNIA_DLL = "C:\path\to\Dunia.dll"
cargo test --test dunia-validation -- --ignored --nocapture

The test parses the file with Portex, reconstructs its sections in disposable heap memory, checks the real patch plans and known RVAs, and applies each patch twice to that copy to verify idempotency. It never loads or executes the game DLL.

License

MIT