Struct CodecTranscodeDecoder 

pub struct CodecTranscodeDecoder<C> { /* private fields */ }

Decodes encoded units into caller-provided value buffers by using a Codec.

CodecTranscodeDecoder is a policy-free bridge from the low-level unchecked Codec contract to Transcoder and TranscodeDecoder. It leaves incomplete input tails in the caller-provided input slice while the stream remains open. Call Transcoder::transcode_eof after upstream EOF so codecs can apply their Codec::decode_eof policy to a trailing prefix.

Type Parameters

• C: Low-level codec used to decode values.

Examples

use qubit_codec::{Codec, CodecTranscodeDecoder};

fn make_decoder<C: Codec>(codec: C) -> CodecTranscodeDecoder<C> {
    CodecTranscodeDecoder::new(codec)
}

Implementations

impl<C> CodecTranscodeDecoder<C>

where C: Codec,

pub fn new(codec: C) -> Self

Creates a buffered decoder backed by codec.

Parameters

• codec: Low-level codec used to decode values.

Returns

Returns a buffered decoder adapter for the supplied codec.

pub fn codec(&self) -> &C

Returns a shared reference to the wrapped codec.

pub fn codec_mut(&mut self) -> &mut C

Returns a mutable reference to the wrapped codec.

Mutating a codec during an active stream can invalidate that stream’s assumptions; reset the adapter before continuing with the new codec configuration.

pub fn into_codec(self) -> C

Consumes the adapter and returns its wrapped codec.

Any buffered lifecycle state and internal hooks are discarded.

Trait Implementations

impl<C: Debug> Debug for CodecTranscodeDecoder<C>

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

Formats the value using the given formatter.

impl<C: Default> Default for CodecTranscodeDecoder<C>

fn default() -> CodecTranscodeDecoder<C>

Returns the “default value” for a type.

impl<C> TranscodeDecoder for CodecTranscodeDecoder<C>

where C: Codec,

type DecodeError = <C as Codec>::DecodeError

Domain error type produced by decode internals.

impl<C> Transcoder for CodecTranscodeDecoder<C>

where C: Codec,

fn max_transcode_output_len( &self, input_len: usize, ) -> Result<usize, CapacityError>

Returns an upper bound for decoded values produced from input_len units.

Parameters

• input_len: Source units the caller plans to decode.

Returns

Returns a conservative upper bound for decoded values.

fn max_finish_output_len(&self) -> Result<usize, CapacityError>

Returns the global maximum values emitted by finishing internal state.

Returns

Returns the number of values that may still be emitted by finishing state.

fn max_reset_output_len(&self) -> Result<usize, CapacityError>

Returns the global maximum values emitted when resetting internal state.

fn reset( &mut self, output: &mut [C::Value], output_index: usize, ) -> Result<usize, TranscodeDecodeErrorOf<C>>

Runs before-reset cleanup for decoder state.

fn transcode( &mut self, input: &[C::Unit], input_index: usize, output: &mut [C::Value], output_index: usize, ) -> Result<TranscodeProgress, TranscodeDecodeErrorOf<C>>

Decodes source units into logical values.

Parameters

• input: Source unit slice.
• input_index: Absolute source index where decoding starts.
• output: Destination value slice.
• output_index: Absolute output value index where writing starts.

Returns

Returns conversion progress for consumed and written counters.

Errors

Returns a decode error when indices are invalid or when conversion fails under hook policy.

fn transcode_eof( &mut self, input: &[C::Unit], input_index: usize, output: &mut [C::Value], output_index: usize, ) -> Result<TranscodeProgress, TranscodeDecodeErrorOf<C>>

Transcodes an input segment while marking it as the end of the stream.

This forwarding implementation lets the engine apply EOF-specific decoder behavior before returning progress to the caller.

fn finish( &mut self, output: &mut [C::Value], output_index: usize, ) -> Result<usize, TranscodeDecodeErrorOf<C>>

Finishes internally retained output after EOF.

Parameters

• output: Destination value slice for final retained values.
• output_index: Absolute output value index where writing starts.

Returns

Returns the number of values written by finalization.

Errors

Returns a finish error if finalization cannot complete.

type Input = <C as Codec>::Unit

Input unit type accepted by this transcoder.

type Output = <C as Codec>::Value

Output unit type produced by this transcoder.

type Error = TranscodeDecodeError<<C as Codec>::DecodeError>

Complete error type produced by this transcoder.

fn max_total_output_len(&self, input_len: usize) -> Result<usize, CapacityError>

Returns an upper bound for a complete reset -> transcode -> finish stream.

fn transcode_complete_into( &mut self, input: &[Self::Input], output: &mut [Self::Output], ) -> Result<usize, Self::Error>

Runs a complete one-shot reset -> transcode -> finish stream.