Struct MessageMut 

pub struct MessageMut<'a> { /* private fields */ }

A safe, writeable wrapper around a CFE message byte slice.

This provides methods to initialize and modify header fields. It is typically used with a SendBuffer from the sb module.

Implementations

impl<'a> MessageMut<'a>

pub fn as_slice(&self) -> &[u8]

Returns the underlying byte slice of the entire message.

pub fn as_mut_slice(&mut self) -> &mut [u8]

Returns the underlying mutable byte slice of the entire message.

pub fn send(self, is_origination: bool) -> Result<()>

Transmits the message in this buffer. The is_origination flag should be set to true if the message is being sent as an original message from this application, or false if it is being relayed.

pub fn init(&mut self, msg_id: MsgId, size: usize) -> Result<()>

Initializes a message header within the buffer.

This routine zeroes the buffer up to size, sets default header fields, and then populates the message ID and length fields.

pub fn set_size(&mut self, size: usize) -> Result<()>

Sets the total size of the message in its header.

pub fn set_msg_id(&mut self, msg_id: MsgId) -> Result<()>

Sets the message ID in the message header.

pub fn set_header_version(&mut self, version: u16) -> Result<()>

Sets the header version in the message header.

pub fn set_apid(&mut self, apid: u16) -> Result<()>

Sets the APID in the message header.

pub fn set_fcn_code(&mut self, fcn_code: u16) -> Result<()>

Sets the function code in a command message header.

Returns an error if the message does not have a secondary command header.

pub fn set_time(&mut self, new_time: SysTime) -> Result<()>

Sets the timestamp in a telemetry message header.

Returns an error if the message does not have a secondary telemetry header.

pub fn set_sequence_count(&mut self, count: u16) -> Result<()>

Sets the sequence count in the message header.

pub fn generate_checksum(&mut self) -> Result<()>

Calculates and sets the checksum field in a command message header.

Returns an error if the message does not have a command secondary header.

pub fn set_type(&mut self, msg_type: MsgType) -> Result<()>

Sets the message type (Command or Telemetry) in the header.

pub fn set_has_secondary_header(&mut self, has_secondary: bool) -> Result<()>

Sets the flag indicating whether a secondary header is present.

pub unsafe fn user_data(&mut self) -> *mut c_void

Gets a raw pointer to the user data portion of the message.

C-API Mapping

This is a wrapper for CFE_SB_GetUserData.

Safety

The caller must ensure the returned pointer is cast to the correct payload struct type and that the size of the payload struct does not exceed the user data length.

pub fn payload<P: Sized>(&mut self) -> Result<&mut P>

Returns a mutable reference to the message payload, interpreted as type P.

This is the primary safe method for accessing the payload of a message. It performs a size check to ensure the payload type P fits within the available user data area of the message buffer, preventing buffer overruns.

Errors

Returns Error::StatusWrongMsgLength if size_of::<P>() is larger than the available user data length in the message buffer.

pub fn user_data_length(&self) -> usize

Gets the length of the user data portion of the message.

pub fn set_user_data_length(&mut self, length: usize)

Sets the length of the user data portion of the message.

pub fn timestamp(&mut self)

Sets the time field in the message header with the current spacecraft time.

pub fn set_segmentation_flag(&mut self, flag: c_uint) -> Result<()>

Sets the segmentation flag in the message header.

pub fn set_eds_version(&mut self, version: u16) -> Result<()>

Sets the EDS version in the message header.

pub fn set_endian(&mut self, endian: c_uint) -> Result<()>

Sets the endianness indicator in the message header.

pub fn set_playback_flag(&mut self, flag: c_uint) -> Result<()>

Sets the playback flag in the message header.

pub fn set_subsystem(&mut self, subsystem: u16) -> Result<()>

Sets the subsystem ID in the message header.

pub fn set_system(&mut self, system: u16) -> Result<()>

Sets the system ID in the message header.

Trait Implementations

impl<'a> Debug for MessageMut<'a>

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

Formats the value using the given formatter.