BitWrap

BitWrap is a derive macro and trait to declare a struct data member with explicit size, in bits.

BitWrap Trait

BitWrap trait declares 2 methods:

rust fn pack(&self, dst: &mut [u8]) -> Result<usize, BitWrapError>

pack method serialize struct fields into dst array

rust fn unpack(&mut self, src: &[u8]) -> Result<usize, BitWrapError>

unpack method deserialize struct fields from src array

BitWrap Macro

```rust use bitwrap::BitWrap;

[derive(BitWrap)]

struct Packet { // Get/Set bit #[bits(1)] flag_1: u8,

// Get/Set bit and convert into bool:
// - 0 - false
// - 1 - true
#[bits(1)]
flag_2: bool,

// Fixed 6 bits
// on 'pack()' set 6 bits to value in the skip option
// on 'unpack()' skip 6 bits
#[bits(6, skip = 0b111111)]

// Get 8 bits and convert them to Enum
// on 'pack()' call 'into(Enum) -> T'
// on 'unpack()' call 'from(T) -> Enum'
// T is a unsigned depends of the bit field size
#[bits(8, from = Enum::from, into = Enum::into)]
variant: Enum,

// call BitWrap methods for Ipv4Addr
#[bits]
ip: std::net::Ipv4Addr

// get value to pack instead of field value
#[bits(8, value = self.data.len())]
len: usize,

// call BitWrap method for Vec<T> with defined
// buffer length where T is u8 or with implemented
// BitWrap + Default traits
#[bytes(self.len)]
data: Vec<u8>,

} ```