binrw helps you write maintainable & easy-to-read declarative binary data readers and writers using ✨macro magic✨.

• Generates efficient data parsers and serialisers for structs and enums using #[derive]
• Reads and writes data from any source using standard io::Read and io::Write streams
• Directives in attributes handle common binary parsing tasks like matching magic numbers, byte ordering, padding & alignment, data validation, and more
• Includes reusable types for common data structures like null-terminated strings and data indirection using offsets
• Parses types from third-party crates using free functions or value maps
• Uses efficient in-memory representations (does not require #[repr(C)] or #[repr(packed)])
• Code in attributes is written as code, not as strings, for improved ergonomics and first-class IDE support
• Supports no_std

#[derive(BinRead)]
#[br(magic = b"DOG", assert(name.len() != 0))]
struct Dog {
    bone_pile_count: u8,

    #[br(big, count = bone_pile_count)]
    bone_piles: Vec<u16>,

    #[br(align_before = 0xA)]
    name: NullString
}

let mut reader = Cursor::new(b"DOG\x02\x00\x01\x00\x12\0\0Rudy\0");
let dog: Dog = reader.read_ne().unwrap();
assert_eq!(dog.bone_piles, &[0x1, 0x12]);
assert_eq!(dog.name.into_string(), "Rudy")

For more information, including a more detailed overview of binrw, visit the documentation.