sigil-wasm · error

#[derive(Debug, Error)]
pub enum WasmError {
    /// Failed to construct or configure the wasmtime engine.
    #[error("wasmtime engine error: {0}")]
    Engine(String),
    /// Failed to compile the supplied bytecode.
    #[error("wasm module compilation failed: {0}")]
    Compile(String),
    /// Failed to instantiate the module against the linker.
    #[error("wasm module instantiation failed: {0}")]
    Instantiate(String),
    /// The contract did not export the required entrypoint or it had
    /// the wrong signature.
    #[error("missing or invalid entrypoint: {0}")]
    BadEntrypoint(String),
    /// The contract trapped during execution. State changes from this
    /// invocation MUST be discarded.
    #[error("contract trapped during execution: {0}")]
    Trap(String),
    /// The contract exhausted its fuel/gas budget.
    #[error("out of fuel (gas exhausted)")]
    OutOfFuel,
    /// Memory access out of bounds (e.g. host pointer/length didn't
    /// fit inside the guest memory).
    #[error("memory access out of bounds: {0}")]
    MemoryOutOfBounds(String),
    /// The host function call returned a typed error to the guest.
    /// Distinct from `Trap` — the guest may have caught and continued.
    #[error("host function error: {0}")]
    Host(#[from] HostError),
    /// Generic catch-all for backend-specific failures.
    #[error("backend error: {0}")]
    Backend(String),
}

#[derive(Debug, Clone, Error, PartialEq, Eq)]
pub enum HostError {
    /// The contract attempted to use a host function it was not granted
    /// in `ContractRecord.allowed_host_functions`.
    #[error("host function `{0}` not in contract allowlist")]
    HostFunctionNotAllowed(String),
    /// The host function was called with malformed arguments (bad
    /// pointer, bad length, malformed UTF-8, etc.).
    #[error("invalid host fn argument: {0}")]
    InvalidArgument(String),
    /// The requested key is not present in contract state.
    #[error("key not found")]
    KeyNotFound,
    /// The host backend rejected the call (e.g. storage error,
    /// compute-marketplace constraint violation).
    #[error("host backend rejected call: {0}")]
    Backend(String),
    /// The contract is not authorised to perform the requested
    /// privileged action (e.g. dispatch_compute without a mandate, or
    /// upgrade outside policy).
    #[error("permission denied: {0}")]
    PermissionDenied(String),
    /// The host backend hit an internal limit (event count, message
    /// queue, etc.).
    #[error("host limit exceeded: {0}")]
    LimitExceeded(String),
}