Struct HostState

pub struct HostState {
    pub allocator: Option<FreeingBumpHeapAllocator>,
    pub panic_message: Option<String>,
}

The state required to construct a HostContext context. The context only lasts for one host call, whereas the state is maintained for the duration of a Wasm runtime call, which may make many different host calls that must share state.

Fields

allocator: Option<FreeingBumpHeapAllocator>

The allocator instance to keep track of allocated memory.

This is stored as an Option as we need to temporarly set this to None when we are allocating/deallocating memory. The problem being that we can only mutable access caller once.

panic_message: Option<String>

Implementations

impl HostState

pub fn new(allocator: FreeingBumpHeapAllocator) -> Self

Constructs a new HostState.

pub fn take_panic_message(&mut self) -> Option<String>

Takes the error message out of the host state, leaving a None in its place.

pub fn allocation_stats(&self) -> AllocationStats