luadec

A Lua 5.1 bytecode decompiler written in Rust.

luadec takes compiled Lua 5.1 bytecode (.luac files) and reconstructs readable Lua source code. It performs control-flow analysis, dominator-tree construction, loop detection, and liveness analysis to produce structured output with proper if/elseif/while/for constructs.

Features

• Decompiles Lua 5.1 bytecode to readable Lua source
• Reconstructs control flow: if/elseif/else, while, repeat/until, numeric for, generic for
• Handles local variable recovery (with or without debug info)
• Supports varargs, closures, and table constructors
• Usable as a library or via the CLI tool

Installation

From Source

git clone <repo-url>
cd luadecng-rs
cargo build --release

The binary will be at target/release/luadec.

Usage

Command Line

# Decompile a .luac file and print to stdout
luadec input.luac

# Decompile and write to a file
luadec input.luac output.lua

# Read from stdin
cat input.luac | luadec -

As a Library

Add luadec-rust to your Cargo.toml:

[dependencies]
luadec-rust = "1"

Simple usage:

let bytecode = std::fs::read("input.luac").unwrap();
let source = luadec_rust::decompile(&bytecode).unwrap();
println!("{}", source);

For more control over the decompilation pipeline:

use luac_parser::lua_bytecode;
use luadec_rust::lua51::lifter::Lifter;
use luadec_rust::lua51::emit;

let data = std::fs::read("input.luac").unwrap();
let (_, bytecode) = lua_bytecode(&data).unwrap();

// Decompile to AST
let func = Lifter::decompile(&bytecode.main_chunk);

// Emit as Lua source
let source = emit::emit_chunk(&func);

Project Structure

Internal Modules (luadec_rust::lua51)

Acknowledgments

The bytecode parser uses luac-parser-rs by metaworm. Thank you for the excellent work on Lua bytecode parsing.

License

MIT