Struct Fragmenter 

pub struct Fragmenter<'a> { /* private fields */ }

Cuts a data block into the fragments of a session, and builds the coded ones.

The block is left where it is: nothing is copied until a fragment is asked for.

Implementations

impl<'a> Fragmenter<'a>

pub fn new( block: &'a [u8], frag_size: u8, ) -> Result<Fragmenter<'a>, LorawanError>

Prepares a block for a session.

Arguments

• block - the data to send.
• frag_size - how many bytes each fragment carries.

Returns

The fragmenter, which says how many fragments the block takes and how much padding the last one needs.

Errors

LorawanError::MalformedFrame for a fragment size of zero or a block that needs more than MAX_FRAGMENTS fragments.

pub const fn nb_frag(&self) -> u16

How many uncoded fragments the block was cut into.

Returns

The count, which the session setup carries as NbFrag.

pub const fn padding(&self) -> u8

How many bytes of padding the last fragment carries.

Returns

The count, which the session setup carries and the receiver strips.

pub const fn frag_size(&self) -> u8

How many bytes each fragment carries.

Returns

The size.

pub fn fragment(&self, n: u16, out: &mut [u8]) -> Result<usize, LorawanError>

Builds one fragment of the session.

Arguments

• n - which fragment, counting from one. Up to nb_frag it is a piece of the block; past that it is a coded fragment, the exclusive-or of a pseudo-random half of the pieces.
• out - where to write it, at least frag_size bytes.

Returns

How many bytes were written, which is always frag_size.

Errors

LorawanError::MalformedFrame for a fragment number of zero, and LorawanError::PayloadTooLong when the buffer is too small.

Trait Implementations

impl<'a> Clone for Fragmenter<'a>

fn clone(&self) -> Fragmenter<'a>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> Copy for Fragmenter<'a>

impl<'a> Debug for Fragmenter<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.