Trait Host

pub trait Host {
    type AdviceProvider: AdviceProvider;

    // Required methods
    fn advice_provider(&self) -> &Self::AdviceProvider;
    fn advice_provider_mut(&mut self) -> &mut Self::AdviceProvider;
    fn get_mast_forest(
        &self,
        node_digest: &RpoDigest,
    ) -> Option<Arc<MastForest>>;

    // Provided methods
    fn on_event(
        &mut self,
        _process: ProcessState<'_>,
        _event_id: u32,
    ) -> Result<(), ExecutionError> { ... }
    fn on_debug(
        &mut self,
        _process: ProcessState<'_>,
        _options: &DebugOptions,
    ) -> Result<(), ExecutionError> { ... }
    fn on_trace(
        &mut self,
        _process: ProcessState<'_>,
        _trace_id: u32,
    ) -> Result<(), ExecutionError> { ... }
    fn on_assert_failed(
        &mut self,
        process: ProcessState<'_>,
        err_code: u32,
    ) -> ExecutionError { ... }
}

Defines an interface by which the VM can interact with the host.

There are four main categories of interactions between the VM and the host:

1. accessing the advice provider,
2. getting a library’s MAST forest,
3. handling advice events (which internally mutates the advice provider), and
4. handling debug and trace events.

Required Associated Types

type AdviceProvider: AdviceProvider

Required Methods

fn advice_provider(&self) -> &Self::AdviceProvider

Returns a reference to the advice provider.

fn advice_provider_mut(&mut self) -> &mut Self::AdviceProvider

Returns a mutable reference to the advice provider.

fn get_mast_forest(&self, node_digest: &RpoDigest) -> Option<Arc<MastForest>>

Returns MAST forest corresponding to the specified digest, or None if the MAST forest for this digest could not be found in this Host.

Provided Methods

fn on_event( &mut self, _process: ProcessState<'_>, _event_id: u32, ) -> Result<(), ExecutionError>

Handles the event emitted from the VM.

fn on_debug( &mut self, _process: ProcessState<'_>, _options: &DebugOptions, ) -> Result<(), ExecutionError>

Handles the debug request from the VM.

fn on_trace( &mut self, _process: ProcessState<'_>, _trace_id: u32, ) -> Result<(), ExecutionError>

Handles the trace emitted from the VM.

fn on_assert_failed( &mut self, process: ProcessState<'_>, err_code: u32, ) -> ExecutionError

Handles the failure of the assertion instruction.

Implementations on Foreign Types

impl<H> Host for &mut H

where H: Host,

type AdviceProvider = <H as Host>::AdviceProvider

fn advice_provider(&self) -> &Self::AdviceProvider

fn advice_provider_mut(&mut self) -> &mut Self::AdviceProvider

fn get_mast_forest(&self, node_digest: &RpoDigest) -> Option<Arc<MastForest>>

fn on_debug( &mut self, process: ProcessState<'_>, options: &DebugOptions, ) -> Result<(), ExecutionError>

fn on_event( &mut self, process: ProcessState<'_>, event_id: u32, ) -> Result<(), ExecutionError>

fn on_trace( &mut self, process: ProcessState<'_>, trace_id: u32, ) -> Result<(), ExecutionError>

fn on_assert_failed( &mut self, process: ProcessState<'_>, err_code: u32, ) -> ExecutionError

Implementors

impl<A: AdviceProvider> Host for DefaultHost<A>

type AdviceProvider = A