Crate bin_layout

Expand description

Very fast! And flexible, This library used to serialize and deserialize data in binary format.

Inspaired by bincode, But much more flexible.

Endianness

By default, the library uses little endian. If you want to use big endian, you can set BE features flag. And for native endian use NE. For example:

[dependencies]
bin-layout = { version = "2", features = ["BE"] }

Example

use bin_layout::DataType;

#[derive(DataType)]
struct Car<'a> {
    name: &'a str,  // Zero-Copy deserialization
    year: u16,
    is_new: bool,
}

#[derive(DataType)]
struct Company<'a> { name: String, cars: Vec<Car<'a>> }

let company = Company {
    name: "Tesla".into(),
    cars: vec![
        Car { name: "Model S", year: 2018, is_new: true },
        Car { name: "Model X", year: 2019, is_new: false },
    ],
};

let mut buf = [0; 64];

company.encode(buf.as_mut()).unwrap();
let company = Company::decode(buf.as_ref()).unwrap();

Data Type

The only trait you need to implement is DataType.

All primitive types implement this trait.

Vec, String, &[T], &str etc.. are encoded with their length value first, Following by each entry.

Variable-Length Integer Encoding

This encoding ensures that smaller integer values need fewer bytes to encode. Support types are L2 and L3, both are encoded in little endian.

By default, L2 (u15) is used to encode length (integer) for record. But you override it by setting L3 (u22) in features flag.

Encoding algorithm is very straightforward, reserving one or two most significant bits of the first byte to encode rest of the length.

L2

MSB	Length	Usable Bits	Range
0	1	7	0..127
1	2	15	0..32767

L3

MSB	Length	Usable Bits	Range
0	1	7	0..127
10	2	14	0..16383
11	3	22	0..4194303

For example, Binary representation of 0x_C0DE is 0x_11_00000011_011110

L3(0x_C0DE) is encoded in 3 bytes:

1st byte: 11_011110      # MSB is 11, so read next 2 bytes
2nd byte:        11
3rd byte:        11

Another example, L3(107) is encoded in just 1 byte:

1st byte: 0_1101011      # MSB is 0, So we don't have to read extra bytes.

Record can be used to represent fixed-size integer to represent the length of a record.

Enums

ErrorKind

Traits

DataType

A trait for serialize and deserialize data for binary format.

Derive

FixedLenInt

Type Definitions

Result

Shortcut for Result<T, bin_layout::ErrorKind>