msgpackin_core

Msgpackin pure Rust MessagePack no_std encoding / decoding library.

If you are looking for Value types or serde integration, see the main msgpackin crate.

This crate:

• is written in pure Rust
• has no dependencies
• is always #![no_std] - there is no feature flag to enable std lib
• never imports the alloc crate - there is no feature flag to do so
• is infallible - there are no error types / Result types
  • the one accommodation to make this happen is that the msgpack "reserved" marker (0xc1) will be decoded as if it were a Nil marker (0xc0)

Example

use msgpackin_core::encode::*;
use msgpackin_core::decode::*;

const S1: &str = "hello ";
const S2: &str = "world!";

// this is a no_std, no alloc crate, everything must be on the stack
let mut buf: [u8; 15] = [0; 15];
let mut cur = 0;

{
    // small helper closure to write consecutive data to our buffer
    let mut write = |data: &[u8]| {
        buf[cur..cur + data.len()].copy_from_slice(data);
        cur += data.len();
    };

    // construct a new encoder
    let mut enc = Encoder::new();

    // write the bytes marking an array msgpack type of length 2
    write(&enc.enc_arr_len(2));

    // write the length of the string we are trying to encode
    write(&enc.enc_str_len(S1.as_bytes().len() as u32));

    // write the actual string bytes
    write(S1.as_bytes());

    // write the second string length
    write(&enc.enc_str_len(S2.as_bytes().len() as u32));

    // write the second string bytes
    write(S2.as_bytes());
}

// make sure we wrote the correct bytes to the buffer
assert_eq!(
    &[
        146, 166, 104, 101, 108, 108, 111, 32, 166, 119, 111, 114, 108,
        100, 33
    ],
    &buf[..]
);

let mut dec = Decoder::new();
let mut iter = dec.parse(&buf);

assert_eq!(Some(Token::Len(LenType::Arr, 2)), iter.next());
assert_eq!(Some(Token::Len(LenType::Str, 6)), iter.next());
assert_eq!(Some(Token::Bin(S1.as_bytes())), iter.next());
assert_eq!(Some(Token::Len(LenType::Str, 6)), iter.next());
assert_eq!(Some(Token::Bin(S2.as_bytes())), iter.next());
assert_eq!(None, iter.next());

License: Apache-2.0