fvm

README

FVM based on EVM

Documentation

Overview

Package ethereum defines interfaces for interacting with Ethereum.

Copyright (c) 2018-2020 The asimov developers Use of this source code is governed by an ISC license that can be found in the LICENSE file.

Index

• Variables
• func CallReadOnlyFunction(from common.Address, block *asiutil.Block, chain ChainContext, ...) (ret []byte, leftOverGas uint64, err error)
• func CanTransfer(view *txo.UtxoViewpoint, block *asiutil.Block, db fvm.StateDB, ...) bool
• func GetHashFn(chain ChainContext) func(n uint64) common.Hash
• func NewFVMContext(from common.Address, gasPrice *big.Int, block *asiutil.Block, ...) fvm.Context
• func PackConstructorArgs(abiStr string, args ...interface{}) ([]byte, error)
• func PackFunctionArgs(abiStr string, funcName string, args ...interface{}) ([]byte, error)
• func Transfer(db fvm.StateDB, sender, recipient common.Address, amount *big.Int, ...)
• func UnPackFunctionResult(abiStr string, v interface{}, funcName string, output []byte) error
• func UnPackReadOnlyResult(abiStr string, funcName string, output []byte) (interface{}, error)
• func UnpackEvent(abiStr string, eventName string, output []byte) (interface{}, error)
• type ChainContext
• type Subscription

Variables

var NotFound = errors.New("not found")

NotFound is returned by API methods if the requested item does not exist.

Functions

func CallReadOnlyFunction

func CallReadOnlyFunction(
	from common.Address,
	block *asiutil.Block,
	chain ChainContext,
	stateDB fvm.StateDB,
	chainConfig *params.ChainConfig,
	gasLimit uint64,
	contractAddr common.Address,
	input []byte) (ret []byte, leftOverGas uint64, err error)

Call a readonly function of a contract

func CanTransfer

func CanTransfer(view *txo.UtxoViewpoint, block *asiutil.Block, db fvm.StateDB, addr common.Address,
	amount *big.Int, vtx *virtualtx.VirtualTransaction, calculateBalanceFunc fvm.CalculateBalanceFunc, assets *protos.Asset) bool

CanTransfer checks whether there are enough funds in the address' account to make a transfer. This does not take the necessary gas in to account to make the transfer valid.

func GetHashFn

func GetHashFn(chain ChainContext) func(n uint64) common.Hash

GetHashFn returns a GetHashFunc which retrieves header hashes by number

func NewFVMContext

func NewFVMContext(from common.Address, gasPrice *big.Int, block *asiutil.Block, chain ChainContext,
	view *txo.UtxoViewpoint,
	voteValue fvm.VoteValueFunc) fvm.Context

NewFVMContext creates a new context of FVM.

func PackConstructorArgs

func PackConstructorArgs(abiStr string, args ...interface{}) ([]byte, error)

Pack constructor with arguments

func PackFunctionArgs

func PackFunctionArgs(abiStr string, funcName string, args ...interface{}) ([]byte, error)

Pack function with arguments

func Transfer

func Transfer(db fvm.StateDB, sender, recipient common.Address, amount *big.Int, vtx *virtualtx.VirtualTransaction, assets *protos.Asset)

Transfer subtracts amount from sender and adds amount to recipient using the given Db

func UnPackFunctionResult

func UnPackFunctionResult(abiStr string, v interface{}, funcName string, output []byte) error

Unpack function execution result

func UnPackReadOnlyResult

func UnPackReadOnlyResult(abiStr string, funcName string, output []byte) (interface{}, error)

Unpack readonly function execution result

func UnpackEvent

func UnpackEvent(abiStr string, eventName string, output []byte) (interface{}, error)

Unpack event

Types

type ChainContext

type ChainContext interface {
	CalculateBalance(view *txo.UtxoViewpoint, block *asiutil.Block, address common.Address, assets *protos.Asset, voucherId int64) (int64, error)
	GetVmConfig() *fvm.Config
	GetTemplateWarehouseInfo() (common.Address, string)
	GetSystemContractInfo(delegateAddr common.Address) (common.Address, []byte, string)
	GetTemplateInfo(contractAddr []byte, gas uint64, block *asiutil.Block, stateDB fvm.StateDB, chainConfig *params.ChainConfig) (uint16, string, uint64)
	FetchTemplate(view *txo.UtxoViewpoint, hash *common.Hash) (uint16, []byte, []byte, []byte, []byte, error)
	BlockHashByHeight(int32) (*common.Hash, error)
}

ChainContext supports retrieving headers and consensus parameters from the current blockchain, which is used during transaction processing.

type Subscription

type Subscription interface {
	// Unsubscribe cancels the sending of events to the data channel
	// and closes the error channel.
	Unsubscribe()
	// Err returns the subscription error channel. The error channel receives
	// a value if there is an issue with the subscription (e.g. the network connection
	// delivering the events has been closed). Only one value will ever be sent.
	// The error channel is closed by Unsubscribe.
	Err() <-chan error
}

Subscription represents an event subscription where events are delivered on a data channel.