Struct Parameter 

pub struct Parameter {
    pub tag: u16,
    pub value: Vec<u8>,
}

One TLV parameter, without its padding — the padding is a property of the encoding, never of the value, and folding it into value is how a decoder starts handing 3 stray zero octets to a user part.

Fields

tag: u16

value: Vec<u8>

Implementations

impl Parameter

pub fn new(tag: u16, value: impl Into<Vec<u8>>) -> Self

pub fn u32(tag: u16, value: u32) -> Self

A parameter whose whole value is one 32-bit field (routing context, error code, …).

pub fn declared_len(&self) -> usize

The value of the Parameter Length field: 4 header octets plus the value, and not the padding (RFC 4666 section 3.2).

pub fn wire_len(&self) -> usize

Octets this parameter occupies on the wire, padding included.

pub fn write_into(&self, out: &mut Vec<u8>) -> Result<(), WireError>

Append the TLV, refusing a value whose Parameter Length would not fit the 16-bit field.

The check comes before anything is written, so a refusal leaves out untouched: a partial TLV would corrupt every parameter after it just as surely as the wrong length did. The old declared as u16 was worse than an oversize parameter — a 65532-octet value makes declared 65536, which narrows to 0, below the 4-octet TLV header itself, so the parameter became unparseable and took every later parameter with it. Silent in release and silent in debug, because a cast does not overflow-check.

pub fn as_u32(&self) -> Option<u32>

The value read as a 32-bit field, or None if it is not exactly four octets.

Trait Implementations

impl Clone for Parameter

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Parameter

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

Formats the value using the given formatter.

impl Eq for Parameter

impl PartialEq for Parameter

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Parameter