Trait nrf_softdevice::ble::l2cap::Packet

pub trait Packet: Sized {
    const MTU: usize;

    // Required methods
    fn allocate() -> Option<NonNull<u8>>;
    fn into_raw_parts(self) -> (NonNull<u8>, usize);
    unsafe fn from_raw_parts(ptr: NonNull<u8>, len: usize) -> Self;
}

A Packet is a byte buffer for packet data. Similar to a Vec<u8> it has a length and a capacity. The capacity however is the fixed value MTU.

You need to implement this trait to give the L2CAP driver a method to allocate and free the space for the packets sent and received on a channel.

Required Associated Constants

const MTU: usize

The maximum size a packet can have.

Required Methods

fn allocate() -> Option<NonNull<u8>>

Allocate a new buffer with space for MTU bytes. Return None when the allocation can’t be fulfilled.

This function is called by the L2CAP driver when it needs space to receive a packet into. It will later call from_raw_parts with the buffer and the amount of bytes it has received.

fn into_raw_parts(self) -> (NonNull<u8>, usize)

Take ownership of the packet buffer. Returns a pointer to the buffer and the number of bytes in the buffer.

To free the memory the driver will call from_raw_parts later and drop the value.

unsafe fn from_raw_parts(ptr: NonNull<u8>, len: usize) -> Self

Construct a Packet from a pointer to a buffer and the number of bytes written to the buffer.

SAFETY: ptr must be a pointer previously returned by either allocate or ìnto_raw_parts. len must be the number of bytes in the buffer and must not be larger than MTU.

Object Safety

This trait is not object safe.

Implementors