Struct FFI_SessionConfig 

#[repr(C)]
pub struct FFI_SessionConfig {
    pub config_options: FFI_ConfigOptions,
    pub clone: unsafe extern "C" fn(plan: &Self) -> Self,
    pub release: unsafe extern "C" fn(arg: &mut Self),
    pub private_data: *mut c_void,
    pub library_marker_id: extern "C" fn() -> usize,
}

A stable struct for sharing SessionConfig across FFI boundaries. Instead of attempting to expose the entire SessionConfig interface, we convert the config options into a map from a string to string and pass those values across the FFI boundary. On the receiver side, we reconstruct a SessionConfig from those values.

It is possible that using different versions of DataFusion across the FFI boundary could have differing expectations of the config options. This is a limitation of this approach, but exposing the entire SessionConfig via a FFI interface would be extensive and provide limited value over this version.

Fields

config_options: FFI_ConfigOptions

FFI stable configuration options.

clone: unsafe extern "C" fn(plan: &Self) -> Self

Used to create a clone on the provider of the execution plan. This should only need to be called by the receiver of the plan.

release: unsafe extern "C" fn(arg: &mut Self)

Release the memory of the private data when it is no longer being used.

private_data: *mut c_void

Internal data. This is only to be accessed by the provider of the plan.

library_marker_id: extern "C" fn() -> usize

Utility to identify when FFI objects are accessed locally through the foreign interface. See crate::get_library_marker_id and the crate’s README.md for more information.

Trait Implementations

impl Clone for FFI_SessionConfig

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FFI_SessionConfig

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

Formats the value using the given formatter.

impl Drop for FFI_SessionConfig

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl From<&SessionConfig> for FFI_SessionConfig

fn from(session: &SessionConfig) -> Self

Converts to this type from the input type.

impl Send for FFI_SessionConfig

impl Sync for FFI_SessionConfig

impl TryFrom<&FFI_SessionConfig> for SessionConfig

type Error = DataFusionError

The type returned in the event of a conversion error.

fn try_from(config: &FFI_SessionConfig) -> Result<Self, Self::Error>

Performs the conversion.