Struct sc_executor_common::runtime_blob::RuntimeBlob

pub struct RuntimeBlob { /* private fields */ }

A bunch of information collected from a WebAssembly module.

Implementations

impl RuntimeBlob

pub fn uncompress_if_needed(wasm_code: &[u8]) -> Result<Self, WasmError>

Create RuntimeBlob from the given wasm code. Will attempt to decompress the code before deserializing it.

See sp_maybe_compressed_blob for details about decompression.

pub fn new(wasm_code: &[u8]) -> Result<Self, WasmError>

Create RuntimeBlob from the given wasm code.

Returns Err if the wasm code cannot be deserialized.

pub fn declared_globals_count(&self) -> u32

The number of globals defined in locally in this module.

pub fn imported_globals_count(&self) -> u32

The number of imports of globals.

pub fn expose_mutable_globals(&mut self)

Perform an instrumentation that makes sure that the mutable globals are exported.

pub fn inject_stack_depth_metering(
    self,
    stack_depth_limit: u32
) -> Result<Self, WasmError>

Run a pass that instrument this module so as to introduce a deterministic stack height limit.

It will introduce a global mutable counter. The instrumentation will increase the counter according to the “cost” of the callee. If the cost exceeds the stack_depth_limit constant, the instrumentation will trap. The counter will be decreased as soon as the the callee returns.

The stack cost of a function is computed based on how much locals there are and the maximum depth of the wasm operand stack.

pub fn entry_point_exists(&self, entry_point: &str) -> bool

Perform an instrumentation that makes sure that a specific function entry_point is exported

pub fn convert_memory_import_into_export(&mut self) -> Result<(), WasmError>

Converts a WASM memory import into a memory section and exports it.

Does nothing if there’s no memory import.

May return an error in case the WASM module is invalid.

pub fn setup_memory_according_to_heap_alloc_strategy(
    &mut self,
    heap_alloc_strategy: HeapAllocStrategy
) -> Result<(), WasmError>

Modifies the blob’s memory section according to the given heap_alloc_strategy.

Will return an error in case there is no memory section present, or if the memory section is empty.

pub fn custom_section_contents(&self, section_name: &str) -> Option<&[u8]>

Scans the wasm blob for the first section with the name that matches the given. Returns the contents of the custom section if found or None otherwise.

pub fn serialize(self) -> Vec<u8>

Consumes this runtime blob and serializes it.

pub fn into_inner(self) -> Module

Destructure this structure into the underlying parity-wasm Module.

Trait Implementations

impl Clone for RuntimeBlob

fn clone(&self) -> RuntimeBlob

Returns a copy of the value.

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

Performs copy-assignment from source.