Crate concordium_smart_contract_engine 

This library provides functionality that builds on top of the Wasm engine and adds high-level functions for executing smart contracts on the Concordium chain.

Concordium supports two versions of smart contracts, the legacy v0 version and the v1 version. The latter is essentially better in every way. They differ in two main ways

• v0 uses message passing for inter-contract communication, and has a flat state. The state is limited to 16kB and the entire state is written every time a contract update is done.
• v1 uses synchronous calls for inter-contract communication, and its state is a trie-based structure, which supports efficient partial state updates. The trie is implemented in the v1::trie module.

Both v0 and v1 modules are structured similarly. The main entrypoints used by users of this library are v0::invoke_init (resp. v1::invoke_init) and v0::invoke_receive (resp. v1::invoke_receive) functions, and their variants.

The respective modules provide more details on the data types involved, and any specifics of the different versions.

Features

This crate has the following features. None are enabled by default.

display-state

This feature exposes the function display_tree for displaying the V1 contract state in a reasonably readable format. This is useful for deep inspection of smart contract state, and debugging.

async

Exposes construction of smart contract state from streams of key-value pairs, such as those received from the node’s API. See

• try_from_stream
• from_stream

enable-ffi

This enables foreign function exports. This is an internal feature and there are no guarantees about the stability of foreign exports.

fuzz-coverage and fuzz

These features are also internal and exist to support fuzzing. They are used to derive Arbitrary instances and to disable inlining, the latter is necessary since the fuzzer used has bugs which prevent the coverage report being generated when functions are inlined.

Re-exports

pub use concordium_wasm as wasm;

Modules

constants

Various constants and functions used by both v0 and v1 execution engines. The constants and functions range from limits on sizes of objects, to costs of different operations.

resumption

This module defines the notion of suspended Wasm computation used by V1 contracts to execute host operations such as transfers and contract calls.

utils

Various utilities for testing and extraction of schemas and build information.

v0

Implementation of execution of V0 contracts.

v1

Implementation of execution of V1 contracts.

Structs

InterpreterEnergy

OutOfEnergy

An error raised by the interpreter when no more interpreter energy remains for execution.

Traits

DebugInfo

Type Aliases

ExecResult

Result of contract execution. This is just a wrapper around anyhow::Result.