Module mavlink 

The C ABI for the MAVLink wire protocol.

MAVLink is the language drones speak, so talking to a PX4 or ArduPilot autopilot means putting exactly the right bytes on the wire and trusting the bytes that come back. This is that byte layer: assembling and parsing v1 and v2 frames, the CRC-16/MCRF4XX checksum every frame carries, the per-message CRC_EXTRA seed that catches a frame whose shape does not match what the receiver expects, and MAVLink 2 signing.

Any dialect, not only the common one

A receiver has to know a message’s CRC_EXTRA before it can check the frame carrying it. The common dialect’s seeds are built in, but a vehicle running a vendor or private dialect uses ids this build has never heard of. Two things keep those reachable: pamoja_mavlink_message_crc_extra derives a seed from a message definition the way the specification does, and a PamojaMavlinkDialect table carries the results, taking precedence over the built-in registry. Nothing here is limited to the ids this crate happens to type.

This module moves a message’s bytes. mavlink_schema is the layer above, which gives those bytes named fields, and mavlink_protocol the one above that, which turns single messages into the mission, command, and offboard exchanges.

Structs

PamojaMavlinkDialect

The CRC_EXTRA seeds of a dialect beyond the common one.

PamojaMavlinkField

One field of a message definition, as the CRC_EXTRA derivation reads it.

PamojaMavlinkFrame

One MAVLink frame, assembled or received.

PamojaMavlinkHeader

The addressing fields a sender stamps on every frame.

PamojaMavlinkParser

A streaming frame parser, and the frames it has completed.

PamojaMavlinkSigner

A signing key and the monotonic timestamp that goes with it.

PamojaMavlinkVerifier

A signing key and the timestamps it has already accepted.

Constants

PAMOJA_MAVLINK_DEFAULT_TIMESTAMP_WINDOW

The default window a verifier accepts a timestamp within, in microseconds.

PAMOJA_MAVLINK_EPOCH_OFFSET_SECS

The Unix time MAVLink counts signing timestamps from, in seconds.

PAMOJA_MAVLINK_IFLAG_SIGNED

The incompatibility flag that marks a v2 frame as signed.

PAMOJA_MAVLINK_KEY_LEN

The length of a signing key, in bytes.

PAMOJA_MAVLINK_MAGIC_V1

The start marker of a v1 frame.

PAMOJA_MAVLINK_MAGIC_V2

The start marker of a v2 frame.

PAMOJA_MAVLINK_MAX_FRAME

The largest frame, in bytes, header, checksum and signature included.

PAMOJA_MAVLINK_MAX_PAYLOAD

The largest payload a frame can carry, in bytes.

PAMOJA_MAVLINK_SIGNATURE_LEN

The length of a v2 signature block, in bytes.

PAMOJA_MAVLINK_VERSION_V1

The original wire format, with a six-byte header.

PAMOJA_MAVLINK_VERSION_V2

The current wire format, with a 24-bit message id, flags, and optional signing.

Functions

pamoja_mavlink_crc16_mcrf4xx^⚠

Returns the CRC-16/MCRF4XX checksum of a byte string.

pamoja_mavlink_dialect_add^⚠

Adds or replaces the CRC_EXTRA seed for a message id.

pamoja_mavlink_dialect_crc_extra^⚠

Returns the seed a dialect resolves a message id to.

pamoja_mavlink_dialect_free^⚠

Releases a dialect table.

pamoja_mavlink_dialect_new

Creates an empty dialect table.

pamoja_mavlink_frame_bytes^⚠

Returns a pointer to a frame’s bytes, ready to put on the wire.

pamoja_mavlink_frame_encode^⚠

Assembles a frame carrying a message.

pamoja_mavlink_frame_free^⚠

Releases a frame.

pamoja_mavlink_frame_header^⚠

Returns the addressing fields a frame carries.

pamoja_mavlink_frame_incompat_flags^⚠

Returns the incompatibility flags a v2 frame declares.

pamoja_mavlink_frame_is_signed^⚠

Reports whether a frame carries a signature.

pamoja_mavlink_frame_message_id^⚠

Returns the id of the message a frame carries.

pamoja_mavlink_frame_parse^⚠

Parses one frame, checking it against a known CRC_EXTRA.

pamoja_mavlink_frame_parse_known^⚠

Parses one frame, looking its CRC_EXTRA up as it goes.

pamoja_mavlink_frame_payload^⚠

Returns a pointer to a frame’s payload.

pamoja_mavlink_frame_signature^⚠

Copies a frame’s signature block out.

pamoja_mavlink_frame_version^⚠

Returns the wire format a frame uses.

pamoja_mavlink_known_crc_extra^⚠

Returns the CRC_EXTRA the common dialect publishes for a message id.

pamoja_mavlink_message_crc_extra^⚠

Derives the CRC_EXTRA seed of a message from its definition.

pamoja_mavlink_parser_free^⚠

Releases a parser.

pamoja_mavlink_parser_new

Creates a parser with an empty buffer.

pamoja_mavlink_parser_next^⚠

Takes the next completed frame out of the parser.

pamoja_mavlink_parser_pending^⚠

Returns how many completed frames are waiting to be taken.

pamoja_mavlink_parser_push^⚠

Feeds bytes off a link into the parser.

pamoja_mavlink_raw_message_to_frame^⚠

Assembles a v2 frame carrying a message this build does not type.

pamoja_mavlink_signer_free^⚠

Releases a signer.

pamoja_mavlink_signer_link_id^⚠

Returns the link a signer signs on.

pamoja_mavlink_signer_new^⚠

Creates a signer.

pamoja_mavlink_signer_sign^⚠

Signs a message into a v2 frame.

pamoja_mavlink_timestamp_from_unix_micros

Converts Unix time into the timestamp MAVLink signing counts in.

pamoja_mavlink_verifier_free^⚠

Releases a verifier.

pamoja_mavlink_verifier_new^⚠

Creates a verifier.

pamoja_mavlink_verifier_set_window^⚠

Sets how far a timestamp may run ahead of the last one accepted.

pamoja_mavlink_verifier_verify^⚠

Checks a frame’s signature and its place in the timestamp sequence.