Struct ByteReader 

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

Reader over bytes, tracking a cursor and the payload name used in errors.

Implementations

impl<'a> ByteReader<'a>

pub fn new(bytes: &'a [u8], label: &'static str) -> Self

A reader positioned at the start of bytes. label names the payload kind in every error this reader produces.

pub fn open_payload( bytes: &'a [u8], magic: u32, header_bytes: usize, label: &'static str, ) -> Result<Self, String>

Open a tagged payload: prove it is long enough to hold a header_bytes header and that it opens with magic, then position the reader just past the magic. Lets a decoder report a short buffer once rather than once per header field.

pub fn position(&self) -> usize

Current byte offset.

pub fn remaining(&self) -> usize

Bytes left between the cursor and the end of the buffer.

pub fn is_empty(&self) -> bool

Whether no bytes remain.

pub fn len(&self) -> usize

Total buffer length, including bytes already consumed.

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

Consume n bytes and return them, or report where the buffer ran out.

pub fn array<const N: usize>(&mut self) -> Result<[u8; N], String>

Consume exactly N bytes as an owned array, ready for from_le_bytes.

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

Read one byte.

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

Read a little-endian u16.

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

Read a little-endian u32.

pub fn u64(&mut self) -> Result<u64, String>

Read a little-endian u64.

pub fn i32(&mut self) -> Result<i32, String>

Read a little-endian i32.

pub fn f32(&mut self) -> Result<f32, String>

Read a little-endian f32.

pub fn skip(&mut self, n: usize) -> Result<(), String>

Advance past n bytes without returning them.

pub fn seek(&mut self, pos: usize) -> Result<(), String>

Move the cursor to an absolute offset, which must lie within the buffer.

pub fn peek(&self, magic: &[u8]) -> bool

Whether the bytes at the cursor equal magic, without consuming them.

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

Everything from the cursor to the end, leaving the cursor in place.

Trait Implementations

impl<'a> Clone for ByteReader<'a>

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

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for ByteReader<'a>

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

Formats the value using the given formatter.