Struct Reader 

pub struct Reader<'a> {
    remaining: &'a [u8],
}

MQTT wire format reader.

All operations are atomic: if any method returns an error, the reader’s state is unchanged.

Fields

remaining: &'a [u8]

Implementations

impl<'a> Reader<'a>

pub const fn new(data: &'a [u8]) -> Self

Creates a new reader over the given data.

pub const fn is_empty(&self) -> bool

Returns true if there are no more bytes to read.

pub const fn remaining(&self) -> &'a [u8]

Returns the remaining unread bytes without consuming them.

const fn duplicate(&self) -> Self

pub const fn take(&mut self, n: usize) -> Result<&'a [u8], DecodeError>

Takes exactly n bytes from the remaining data, returning a slice.

Errors

Returns DecodeError::InsufficientData if fewer than n bytes remain.

pub const fn u8(&mut self) -> Result<u8, DecodeError>

Reads a single byte.

Errors

Returns DecodeError::InsufficientData if no bytes remain.

pub const fn u16(&mut self) -> Result<u16, DecodeError>

Reads a big-endian u16.

Errors

Returns DecodeError::InsufficientData if fewer than 2 bytes remain.

pub const fn u32(&mut self) -> Result<u32, DecodeError>

Reads a big-endian u32.

Errors

Returns DecodeError::InsufficientData if fewer than 4 bytes remain.

pub const fn vbi(&mut self) -> Result<Vbi, DecodeError>

Reads a Variable Byte Integer (1–4 bytes).

Errors

Returns DecodeError::InsufficientData if the input is truncated, or DecodeError::MalformedVbi if the encoding is invalid.

pub const fn binary(&mut self) -> Result<&'a MqttBytes, DecodeError>

Reads a length-prefixed binary data.

Errors

Returns DecodeError::InsufficientData if the input is truncated.

pub const fn string(&mut self) -> Result<&'a MqttStr, DecodeError>

Reads a length-prefixed UTF-8 string with additional MQTT validation.

Errors

Returns DecodeError::InsufficientData if the input is truncated, DecodeError::InvalidUtf8 if the string is not valid UTF-8, or DecodeError::StringContainsNull if the string contains a null byte.

pub const fn string_pair( &mut self, ) -> Result<(&'a MqttStr, &'a MqttStr), DecodeError>

Reads a pair of length-prefixed UTF-8 strings with additional MQTT validation.

Errors

Returns DecodeError if either string cannot be read or is invalid.

Trait Implementations

impl<'a> Clone for Reader<'a>

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

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for Reader<'a>

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

Formats the value using the given formatter.