Module framing 

Frame extraction strategies.

A Framer is a stateless protocol that locates and emits one frame at a time from a borrowed byte slice. Frames are described by Frame, which carries a zero-copy reference to the payload alongside the count of bytes the framer consumed from the input.

Concrete framers shipped with the crate:

• length::LengthPrefixed for fixed-width length-prefixed protocols (1, 2, 3, 4, or 8 byte prefixes, either byte order, optional length adjustment).
• varint_prefixed::VarintPrefixed for LEB128 length-prefixed messages, the “length-delimited” framing used by Protocol Buffers and gRPC-style transports.
• delimiter::Delimited for byte-delimited protocols such as newline- terminated text.
• checksummed::Checksummed, a decorator that appends and verifies a CRC (or any Checksum) after the frames of any other framer.

Custom framers are implemented by writing a Framer impl on a user-defined type.

Untrusted input

A framer only guards memory if it has a limit. Use the bounded constructors (LengthPrefixed::bounded, Delimited::bounded) or with_max_payload for any stream that comes from a peer you do not control. VarintPrefixed::new is bounded by default.

When bytes arrive in pieces, drive the framer through a StreamDecoder (or Framer::next_frame_from) so that a delimiter search resumes where the previous call stopped instead of rescanning the whole buffer. That keeps the total work linear in the input size even when a peer drips one byte at a time.

Re-exports

pub use checksummed::ChecksumScope;

pub use checksummed::Checksummed;

pub use delimiter::Delimited;

pub use length::Endian;

pub use length::LengthPrefixed;

pub use length::LengthWidth;

pub use varint_prefixed::VarintPrefixed;

Modules

checksummed

Checksum-trailer framing.

delimiter

Byte-delimited framing.

length

Length-prefixed framing.

varint_prefixed

Varint length-prefixed framing.

Structs

Frame

A frame extracted from an input byte slice.

StreamDecoder

Stateful wrapper that drives a Framer over a growing input buffer.

Traits

Framer

Strategy that extracts and emits one frame at a time.