Struct CdsBlock 

pub struct CdsBlock<T: Copy + Sized> { /* private fields */ }

A handle to a block of data in the cFE Critical Data Store.

This struct is generic over the data type T to be stored. The underlying CDS block is registered when new is called and persists for the life of the cFE instance (across resets).

The type T must be Copy and Sized, as the underlying CFE API performs a raw byte copy of the data.

Implementations

impl<T: Copy + Sized> CdsBlock<T>

pub fn new(name: &str) -> Result<(Self, CdsInfo)>

Registers a new CDS block with the given name or retrieves an existing one.

This function will attempt to create a CDS block of size_of::<T>(). The block contents are NOT cleared or initialized on creation.

If a block with this name already existed but with a different size, it is replaced. The new block contains uninitialized data and CdsInfo::Created is returned (not Restored).

Return Value

On success, returns Ok((CdsBlock, CdsInfo)). The CdsInfo indicates whether the block was newly created or was restored from a previous run.

• If CdsInfo::Created, the application is responsible for initializing the data by calling store().
• If CdsInfo::Restored, the application can immediately call restore() to retrieve the previous state.

Arguments

• name: A unique, application-local name for the CDS block.

pub fn store(&self, data: &T) -> Result<()>

Stores a copy of data into the CDS block.

This should be called after new reports CdsInfo::Created, or any time the application wishes to update the persistent state.

pub fn restore_or_default(name: &str) -> Result<(Self, T)>

where T: Default,

Creates a CDS block and restores previous state, or uses T::default() if the block is new or corrupted.

pub fn restore(&self) -> Result<T>

Restores the contents of the CDS block into a new instance of T.

This will perform a raw byte copy from the CDS into the returned struct. It is safe because T is constrained to be Copy.

Returns Err if the data in the CDS has been corrupted (e.g. CRC mismatch). The corrupted data is not returned.

pub fn handle(&self) -> CdsHandle

Returns the underlying CDS handle.

pub fn get_id_by_name(name: &str) -> Result<CdsHandle>

Finds an existing CDS Block ID by its full name (“AppName.CDSName”).

Trait Implementations

impl<T: Debug + Copy + Sized> Debug for CdsBlock<T>

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

Formats the value using the given formatter.