Struct trust_dns::serialize::binary::BinDecoder

pub struct BinDecoder<'a> { /* fields omitted */ }

This is non-destructive to the inner buffer, b/c for pointer types we need to perform a reverse seek to lookup names

A note on serialization, there was a thought to have this implement the Serde deserializer, but given that this is such a small subset of all the serialization which that performs this is a simpler implementation without the cruft, at least for serializing to/from the binary DNS protocols.

Methods

impl<'a> BinDecoder<'a>

pub fn new(buffer: &'a [u8]) -> BinDecoder<'a>

Creates a new BinDecoder

Arguments

• buffer - buffer from which all data will be read

pub fn pop(&mut self) -> Result<Restrict<u8>, ProtoError>

Pop one byte from the buffer

pub fn len(&self) -> usize

Returns the number of bytes in the buffer

use trust_dns_proto::serialize::binary::BinDecoder;

let deadbeef = b"deadbeef";
let mut decoder = BinDecoder::new(deadbeef);
assert_eq!(decoder.len(), 8);
decoder.read_slice(7).unwrap();
assert_eq!(decoder.len(), 1);

pub fn is_empty(&self) -> bool

Returns true if the buffer is empty

pub fn peek(&self) -> Option<Restrict<u8>>

Peed one byte forward, without moving the current index forward

pub fn index(&self) -> usize

Returns the current index in the buffer

pub fn clone(&self, index_at: u16) -> BinDecoder<'a>

This is a pretty efficient clone, as the buffer is never cloned, and only the index is set to the value passed in

pub fn read_character_data(&mut self) -> Result<Restrict<&[u8]>, ProtoError>

Reads a String from the buffer

<character-string> is a single
length octet followed by that number of characters.  <character-string>
is treated as binary information, and can be up to 256 characters in
length (including the length octet).

Returns

A String version of the character data

pub fn read_character_data_max(     &mut self,     max_len: Option<usize> ) -> Result<Restrict<&[u8]>, ProtoError>

Reads to a maximum length of data, returns an error if this is exceeded

pub fn read_vec(&mut self, len: usize) -> Result<Restrict<Vec<u8>>, ProtoError>

Reads a Vec out of the buffer

Arguments

• len - number of bytes to read from the buffer

Returns

The Vec of the specified length, otherwise an error

pub fn read_slice(     &mut self,     len: usize ) -> Result<Restrict<&'a [u8]>, ProtoError>

Reads a slice out of the buffer, without allocating

Arguments

• len - number of bytes to read from the buffer

Returns

The slice of the specified length, otherwise an error

pub fn slice_from(&self, index: usize) -> Result<&'a [u8], ProtoError>

Reads a slice from a previous index to the current

pub fn read_u8(&mut self) -> Result<Restrict<u8>, ProtoError>

Reads a byte from the buffer, equivalent to Self::pop()

pub fn read_u16(&mut self) -> Result<Restrict<u16>, ProtoError>

Reads the next 2 bytes into u16

This performs a byte-by-byte manipulation, there which means endianness is implicitly handled (i.e. no network to little endian (intel), issues)

Return

Return the u16 from the buffer

pub fn read_i32(&mut self) -> Result<Restrict<i32>, ProtoError>

Reads the next four bytes into i32.

This performs a byte-by-byte manipulation, there which means endianness is implicitly handled (i.e. no network to little endian (intel), issues)

Return

Return the i32 from the buffer

pub fn read_u32(&mut self) -> Result<Restrict<u32>, ProtoError>

Reads the next four bytes into u32.

This performs a byte-by-byte manipulation, there which means endianness is implicitly handled (i.e. no network to little endian (intel), issues)

Return

Return the u32 from the buffer