Python-style Object Allocator in Rust (obmalloc)

This project implements a Python-inspired object allocator in Rust, focusing on memory pool management and custom allocation strategies similar to CPython's obmalloc.

Features

• Custom memory allocator implementing GlobalAlloc trait
• Pool-based memory management with linked list structure
• Reference counting using Arc<Mutex<u32>> for safe concurrent access
• Memory pool headers tracking allocation metadata
• Thread-safe operations through mutex-protected reference counts
• Comprehensive error handling for allocation failures

Implementation Details

The allocator features:

• PoolHeader struct tracking:
  • Reference counts
  • Free block pointers
  • Pool linking (next/previous)
  • Allocation metadata (size index, arena index, offsets)
• PoolHeaderRef union for efficient memory usage
• Custom allocation functions with proper alignment handling
• Testable interface with panic-safe execution

Getting Started

Prerequisites

• Rust 1.60+ (edition 2021)
• Cargo package manager

Building

git clone https://github.com/yourusername/obmalloc.git
cd obmalloc
cargo build

Running Tests

cargo test

As a Static Library

Configured in Cargo.toml for integration into other projects:

[lib]
crate-type = ["staticlib"]

Usage Example

use obmalloc::{allocate_pool, manage_memory_pools};

fn main() {
    // Allocate raw memory block
    let block = unsafe { allocate_pool(1024).unwrap() };
    
    // Manage memory pools
    manage_memory_pools().expect("Memory management failed");
    
    // ... use allocated memory ...
}

Performance Considerations

The implementation balances safety and performance by:

1. Using ManuallyDrop for precise control over ARC drops
2. Leveraging Rust's ownership system for memory safety
3. Implementing mutex guards only when modifying reference counts
4. Providing direct memory access through raw pointers where appropriate

License

MIT License - see LICENSE file for details

Contribution

Contributions are welcome! Please submit issues and pull requests through GitHub.