Overview

Facilitates decoding of data frames using the HDLC protocol by returning packets as they are decoded and storing incomplete data frames in a buffer.

Decoder does not own the buffer it writes to. It can be used to write bytes to any buffer. The DecoderBuffer template class allocates a buffer.

Inheritance diagram for pw::hdlc::Decoder:

Public Member Functions
constexpr	Decoder (ByteSpan buffer)

	Decoder (const Decoder &)=delete

Decoder &	operator= (const Decoder &)=delete

	Decoder (Decoder &&)=default

Decoder &	operator= (Decoder &&)=default

Result< Frame >	Process (std::byte new_byte)
	Parses a single byte of an HDLC stream.

template<typename F , typename... Args>
void	Process (ConstByteSpan data, F &&callback, Args &&... args)
	Processes a span of data and calls the provided callback with each frame or error.

size_t	max_size () const

void	Clear ()
	Clears and resets the decoder.

Static Public Member Functions
static constexpr size_t	RequiredBufferSizeForFrameSize (size_t max_frame_size)

Member Function Documentation

size_t pw::hdlc::Decoder::max_size ( ) const

inline

Result< Frame > pw::hdlc::Decoder::Process ( std::byte new_byte )

Parses a single byte of an HDLC stream.

Returns

A Result containing the decoded frame on success or one of the following error codes on failure:

UNAVAILABLE - No frame is available.
RESOURCE_EXHAUSTED - A frame completed, but it was too large to fit in the decoder's buffer.
DATA_LOSS - A frame completed, but it was invalid. The frame was incomplete or the frame check sequence verification failed.

static constexpr size_t pw::hdlc::Decoder::RequiredBufferSizeForFrameSize ( size_t max_frame_size )

inlinestaticconstexpr

Returns: The buffer space required for a Decoder to successfully decode a frame whose on-the-wire HDLC encoded size does not exceed max_frame_size.

The documentation for this class was generated from the following file: