forked from celo-org/celo-blockchain
/
evm.go
659 lines (581 loc) · 25 KB
/
evm.go
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// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package vm
import (
"bytes"
"encoding/binary"
goerrors "errors"
"math/big"
"sync/atomic"
"time"
abipkg "github.com/keep-network/celo-blockchain/accounts/abi"
"github.com/keep-network/celo-blockchain/common"
"github.com/keep-network/celo-blockchain/common/hexutil"
"github.com/keep-network/celo-blockchain/consensus"
"github.com/keep-network/celo-blockchain/core/types"
"github.com/keep-network/celo-blockchain/crypto"
"github.com/keep-network/celo-blockchain/log"
"github.com/keep-network/celo-blockchain/params"
)
// emptyCodeHash is used by create to ensure deployment is disallowed to already
// deployed contract addresses (relevant after the account abstraction).
var emptyCodeHash = crypto.Keccak256Hash(nil)
// systemCaller is the caller when the EVM is invoked from the within the blockchain system.
var systemCaller = AccountRef(common.HexToAddress("0x0"))
type (
// CanTransferFunc is the signature of a transfer guard function
CanTransferFunc func(StateDB, common.Address, *big.Int) bool
// TransferFunc is the signature of a transfer function
TransferFunc func(StateDB, common.Address, common.Address, *big.Int)
// GetHashFunc returns the n'th block hash in the blockchain
// and is used by the BLOCKHASH EVM op code.
GetHashFunc func(uint64) common.Hash
// GetHeaderByNumber returns the header of the nth block in the chain.
GetHeaderByNumberFunc func(uint64) *types.Header
// VerifySealFunc returns true if the given header contains a valid seal
// according to the engine's consensus rules.
VerifySealFunc func(*types.Header) bool
)
// run runs the given contract and takes care of running precompiles with a fallback to the byte code interpreter.
func run(evm *EVM, contract *Contract, input []byte, readOnly bool) ([]byte, error) {
if contract.CodeAddr != nil {
precompiles := PrecompiledContractsHomestead
if evm.chainRules.IsByzantium {
precompiles = PrecompiledContractsByzantium
}
if evm.chainRules.IsIstanbul {
precompiles = PrecompiledContractsIstanbul
}
if evm.chainRules.IsDonut {
precompiles = PrecompiledContractsDonut
}
if p := precompiles[*contract.CodeAddr]; p != nil {
return RunPrecompiledContract(p, input, contract, evm)
}
}
for _, interpreter := range evm.interpreters {
if interpreter.CanRun(contract.Code) {
if evm.interpreter != interpreter {
// Ensure that the interpreter pointer is set back
// to its current value upon return.
defer func(i Interpreter) {
evm.interpreter = i
}(evm.interpreter)
evm.interpreter = interpreter
}
return interpreter.Run(contract, input, readOnly)
}
}
return nil, ErrNoCompatibleInterpreter
}
// Context provides the EVM with auxiliary information. Once provided
// it shouldn't be modified.
type Context struct {
// CanTransfer returns whether the account contains
// sufficient ether to transfer the value
CanTransfer CanTransferFunc
// Transfer transfers ether from one account to the other
Transfer TransferFunc
// GetHash returns the hash corresponding to n
GetHash GetHashFunc
// GetParentSealBitmap returns the parent seal bitmap corresponding to n
GetHeaderByNumber GetHeaderByNumberFunc
// VerifySeal verifies or returns an error for the given header
VerifySeal VerifySealFunc
// Message information
Origin common.Address // Provides information for ORIGIN
GasPrice *big.Int // Provides information for GASPRICE
// Block information
Coinbase common.Address // Provides information for COINBASE
BlockNumber *big.Int // Provides information for NUMBER
Time *big.Int // Provides information for TIME
Header *types.Header
Engine consensus.Engine
}
// EVM is the Ethereum Virtual Machine base object and provides
// the necessary tools to run a contract on the given state with
// the provided context. It should be noted that any error
// generated through any of the calls should be considered a
// revert-state-and-consume-all-gas operation, no checks on
// specific errors should ever be performed. The interpreter makes
// sure that any errors generated are to be considered faulty code.
//
// The EVM should never be reused and is not thread safe.
type EVM struct {
// Context provides auxiliary blockchain related information
Context
// StateDB gives access to the underlying state
StateDB StateDB
// Depth is the current call stack
depth int
// chainConfig contains information about the current chain
chainConfig *params.ChainConfig
// chain rules contains the chain rules for the current epoch
chainRules params.Rules
// virtual machine configuration options used to initialise the
// evm.
vmConfig Config
// global (to this context) ethereum virtual machine
// used throughout the execution of the tx.
interpreters []Interpreter
interpreter Interpreter
// abort is used to abort the EVM calling operations
// NOTE: must be set atomically
abort int32
// callGasTemp holds the gas available for the current call. This is needed because the
// available gas is calculated in gasCall* according to the 63/64 rule and later
// applied in opCall*.
callGasTemp uint64
DontMeterGas bool
}
// NewEVM returns a new EVM. The returned EVM is not thread safe and should
// only ever be used *once*.
func NewEVM(ctx Context, statedb StateDB, chainConfig *params.ChainConfig, vmConfig Config) *EVM {
evm := &EVM{
Context: ctx,
StateDB: statedb,
vmConfig: vmConfig,
chainConfig: chainConfig,
chainRules: chainConfig.Rules(ctx.BlockNumber),
interpreters: make([]Interpreter, 0, 1),
DontMeterGas: false,
}
if chainConfig.IsEWASM(ctx.BlockNumber) {
// to be implemented by EVM-C and Wagon PRs.
// if vmConfig.EWASMInterpreter != "" {
// extIntOpts := strings.Split(vmConfig.EWASMInterpreter, ":")
// path := extIntOpts[0]
// options := []string{}
// if len(extIntOpts) > 1 {
// options = extIntOpts[1..]
// }
// evm.interpreters = append(evm.interpreters, NewEVMVCInterpreter(evm, vmConfig, options))
// } else {
// evm.interpreters = append(evm.interpreters, NewEWASMInterpreter(evm, vmConfig))
// }
panic("No supported ewasm interpreter yet.")
}
// vmConfig.EVMInterpreter will be used by EVM-C, it won't be checked here
// as we always want to have the built-in EVM as the failover option.
evm.interpreters = append(evm.interpreters, NewEVMInterpreter(evm, &evm.vmConfig))
evm.interpreter = evm.interpreters[0]
return evm
}
// Cancel cancels any running EVM operation. This may be called concurrently and
// it's safe to be called multiple times.
func (evm *EVM) Cancel() {
atomic.StoreInt32(&evm.abort, 1)
}
// Cancelled returns true if Cancel has been called
func (evm *EVM) Cancelled() bool {
return atomic.LoadInt32(&evm.abort) == 1
}
// Interpreter returns the current interpreter
func (evm *EVM) Interpreter() Interpreter {
return evm.interpreter
}
func (evm *EVM) GetStateDB() StateDB {
return evm.StateDB
}
func (evm *EVM) GetHeader() *types.Header {
return evm.Context.Header
}
func (evm *EVM) GetDebug() bool {
return evm.vmConfig.Debug
}
func (evm *EVM) SetDebug(value bool) {
evm.vmConfig.Debug = value
}
// Call executes the contract associated with the addr with the given input as
// parameters. It also handles any necessary value transfer required and takes
// the necessary steps to create accounts and reverses the state in case of an
// execution error or failed value transfer.
func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas uint64, value *big.Int) (ret []byte, leftOverGas uint64, err error) {
if evm.vmConfig.NoRecursion && evm.depth > 0 {
return nil, gas, nil
}
// Fail if we're trying to execute above the call depth limit
if evm.depth > int(params.CallCreateDepth) {
return nil, gas, ErrDepth
}
// Fail if we're trying to transfer more than the available balance
if !evm.Context.CanTransfer(evm.StateDB, caller.Address(), value) {
return nil, gas, ErrInsufficientBalance
}
var (
to = AccountRef(addr)
snapshot = evm.StateDB.Snapshot()
)
if !evm.StateDB.Exist(addr) {
precompiles := PrecompiledContractsHomestead
if evm.chainRules.IsByzantium {
precompiles = PrecompiledContractsByzantium
}
if evm.chainRules.IsIstanbul {
precompiles = PrecompiledContractsIstanbul
}
if evm.chainRules.IsDonut {
precompiles = PrecompiledContractsDonut
}
if precompiles[addr] == nil && evm.chainRules.IsEIP158 && value.Sign() == 0 {
// Calling a non existing account, don't do anything, but ping the tracer
if evm.vmConfig.Debug && evm.depth == 0 {
evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
evm.vmConfig.Tracer.CaptureEnd(ret, 0, 0, nil)
}
return nil, gas, nil
}
evm.StateDB.CreateAccount(addr)
}
gas, err = evm.TobinTransfer(evm.StateDB, caller.Address(), to.Address(), gas, value)
if err != nil {
log.Error("Failed to transfer with tobin tax", "err", err)
return nil, gas, err
}
// Initialise a new contract and set the code that is to be used by the EVM.
// The contract is a scoped environment for this execution context only.
contract := NewContract(caller, to, value, gas)
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
// Even if the account has no code, we need to continue because it might be a precompile
start := time.Now()
// Capture the tracer start/end events in debug mode
if evm.vmConfig.Debug && evm.depth == 0 {
evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
defer func() { // Lazy evaluation of the parameters
evm.vmConfig.Tracer.CaptureEnd(ret, gas-contract.Gas, time.Since(start), err)
}()
}
ret, err = run(evm, contract, input, false)
// When an error was returned by the EVM or when setting the creation code
// above we revert to the snapshot and consume any gas remaining. Additionally
// when we're in homestead this also counts for code storage gas errors.
if err != nil {
evm.StateDB.RevertToSnapshot(snapshot)
if err != errExecutionReverted {
contract.UseGas(contract.Gas)
}
}
return ret, contract.Gas, err
}
// CallCode executes the contract associated with the addr with the given input
// as parameters. It also handles any necessary value transfer required and takes
// the necessary steps to create accounts and reverses the state in case of an
// execution error or failed value transfer.
//
// CallCode differs from Call in the sense that it executes the given address'
// code with the caller as context.
func (evm *EVM) CallCode(caller ContractRef, addr common.Address, input []byte, gas uint64, value *big.Int) (ret []byte, leftOverGas uint64, err error) {
if evm.vmConfig.NoRecursion && evm.depth > 0 {
return nil, gas, nil
}
// Fail if we're trying to execute above the call depth limit
if evm.depth > int(params.CallCreateDepth) {
return nil, gas, ErrDepth
}
// Fail if we're trying to transfer more than the available balance
if !evm.CanTransfer(evm.StateDB, caller.Address(), value) {
return nil, gas, ErrInsufficientBalance
}
var (
snapshot = evm.StateDB.Snapshot()
to = AccountRef(caller.Address())
)
// Initialise a new contract and set the code that is to be used by the EVM.
// The contract is a scoped environment for this execution context only.
contract := NewContract(caller, to, value, gas)
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
ret, err = run(evm, contract, input, false)
if err != nil {
evm.StateDB.RevertToSnapshot(snapshot)
if err != errExecutionReverted {
contract.UseGas(contract.Gas)
}
}
return ret, contract.Gas, err
}
// DelegateCall executes the contract associated with the addr with the given input
// as parameters. It reverses the state in case of an execution error.
//
// DelegateCall differs from CallCode in the sense that it executes the given address'
// code with the caller as context and the caller is set to the caller of the caller.
func (evm *EVM) DelegateCall(caller ContractRef, addr common.Address, input []byte, gas uint64) (ret []byte, leftOverGas uint64, err error) {
if evm.vmConfig.NoRecursion && evm.depth > 0 {
return nil, gas, nil
}
// Fail if we're trying to execute above the call depth limit
if evm.depth > int(params.CallCreateDepth) {
return nil, gas, ErrDepth
}
var (
snapshot = evm.StateDB.Snapshot()
to = AccountRef(caller.Address())
)
// Initialise a new contract and make initialise the delegate values
contract := NewContract(caller, to, nil, gas).AsDelegate()
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
ret, err = run(evm, contract, input, false)
if err != nil {
evm.StateDB.RevertToSnapshot(snapshot)
if err != errExecutionReverted {
contract.UseGas(contract.Gas)
}
}
return ret, contract.Gas, err
}
// StaticCall executes the contract associated with the addr with the given input
// as parameters while disallowing any modifications to the state during the call.
// Opcodes that attempt to perform such modifications will result in exceptions
// instead of performing the modifications.
func (evm *EVM) StaticCall(caller ContractRef, addr common.Address, input []byte, gas uint64) (ret []byte, leftOverGas uint64, err error) {
if evm.vmConfig.NoRecursion && evm.depth > 0 {
return nil, gas, nil
}
// Fail if we're trying to execute above the call depth limit
if evm.depth > int(params.CallCreateDepth) {
return nil, gas, ErrDepth
}
var (
to = AccountRef(addr)
snapshot = evm.StateDB.Snapshot()
)
// Initialise a new contract and set the code that is to be used by the EVM.
// The contract is a scoped environment for this execution context only.
contract := NewContract(caller, to, new(big.Int), gas)
contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
// We do an AddBalance of zero here, just in order to trigger a touch.
// This doesn't matter on Mainnet, where all empties are gone at the time of Byzantium,
// but is the correct thing to do and matters on other networks, in tests, and potential
// future scenarios
evm.StateDB.AddBalance(addr, bigZero)
// When an error was returned by the EVM or when setting the creation code
// above we revert to the snapshot and consume any gas remaining. Additionally
// when we're in Homestead this also counts for code storage gas errors.
ret, err = run(evm, contract, input, true)
if err != nil {
evm.StateDB.RevertToSnapshot(snapshot)
if err != errExecutionReverted {
contract.UseGas(contract.Gas)
}
}
return ret, contract.Gas, err
}
type codeAndHash struct {
code []byte
hash common.Hash
}
func (c *codeAndHash) Hash() common.Hash {
if c.hash == (common.Hash{}) {
c.hash = crypto.Keccak256Hash(c.code)
}
return c.hash
}
// create creates a new contract using code as deployment code.
func (evm *EVM) create(caller ContractRef, codeAndHash *codeAndHash, gas uint64, value *big.Int, address common.Address) ([]byte, common.Address, uint64, error) {
// Depth check execution. Fail if we're trying to execute above the
// limit.
if evm.depth > int(params.CallCreateDepth) {
return nil, common.Address{}, gas, ErrDepth
}
if !evm.CanTransfer(evm.StateDB, caller.Address(), value) {
return nil, common.Address{}, gas, ErrInsufficientBalance
}
nonce := evm.StateDB.GetNonce(caller.Address())
evm.StateDB.SetNonce(caller.Address(), nonce+1)
// Ensure there's no existing contract already at the designated address
contractHash := evm.StateDB.GetCodeHash(address)
if evm.StateDB.GetNonce(address) != 0 || (contractHash != (common.Hash{}) && contractHash != emptyCodeHash) {
return nil, common.Address{}, 0, ErrContractAddressCollision
}
// Create a new account on the state
snapshot := evm.StateDB.Snapshot()
evm.StateDB.CreateAccount(address)
if evm.chainRules.IsEIP158 {
evm.StateDB.SetNonce(address, 1)
}
gas, err := evm.TobinTransfer(evm.StateDB, caller.Address(), address, gas, value)
if err != nil {
log.Error("Failed to transfer with tobin tax", "err", err)
return nil, address, gas, err
}
// Initialise a new contract and set the code that is to be used by the EVM.
// The contract is a scoped environment for this execution context only.
contract := NewContract(caller, AccountRef(address), value, gas)
contract.SetCodeOptionalHash(&address, codeAndHash)
if evm.vmConfig.NoRecursion && evm.depth > 0 {
return nil, address, gas, nil
}
if evm.vmConfig.Debug && evm.depth == 0 {
evm.vmConfig.Tracer.CaptureStart(caller.Address(), address, true, codeAndHash.code, gas, value)
}
start := time.Now()
ret, err := run(evm, contract, nil, false)
// check whether the max code size has been exceeded
maxCodeSizeExceeded := evm.chainRules.IsEIP158 && len(ret) > params.MaxCodeSize
// if the contract creation ran successfully and no errors were returned
// calculate the gas required to store the code. If the code could not
// be stored due to not enough gas set an error and let it be handled
// by the error checking condition below.
if err == nil && !maxCodeSizeExceeded {
createDataGas := uint64(len(ret)) * params.CreateDataGas
if contract.UseGas(createDataGas) {
evm.StateDB.SetCode(address, ret)
} else {
err = ErrCodeStoreOutOfGas
}
}
// When an error was returned by the EVM or when setting the creation code
// above we revert to the snapshot and consume any gas remaining. Additionally
// when we're in homestead this also counts for code storage gas errors.
if maxCodeSizeExceeded || (err != nil && (evm.chainRules.IsHomestead || err != ErrCodeStoreOutOfGas)) {
evm.StateDB.RevertToSnapshot(snapshot)
if err != errExecutionReverted {
contract.UseGas(contract.Gas)
}
}
// Assign err if contract code size exceeds the max while the err is still empty.
if maxCodeSizeExceeded && err == nil {
err = errMaxCodeSizeExceeded
}
if evm.vmConfig.Debug && evm.depth == 0 {
evm.vmConfig.Tracer.CaptureEnd(ret, gas-contract.Gas, time.Since(start), err)
}
return ret, address, contract.Gas, err
}
// Create creates a new contract using code as deployment code.
func (evm *EVM) Create(caller ContractRef, code []byte, gas uint64, value *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
contractAddr = crypto.CreateAddress(caller.Address(), evm.StateDB.GetNonce(caller.Address()))
return evm.create(caller, &codeAndHash{code: code}, gas, value, contractAddr)
}
// Create2 creates a new contract using code as deployment code.
//
// The different between Create2 with Create is Create2 uses sha3(0xff ++ msg.sender ++ salt ++ sha3(init_code))[12:]
// instead of the usual sender-and-nonce-hash as the address where the contract is initialized at.
func (evm *EVM) Create2(caller ContractRef, code []byte, gas uint64, endowment *big.Int, salt *big.Int) (ret []byte, contractAddr common.Address, leftOverGas uint64, err error) {
codeAndHash := &codeAndHash{code: code}
contractAddr = crypto.CreateAddress2(caller.Address(), common.BigToHash(salt), codeAndHash.Hash().Bytes())
return evm.create(caller, codeAndHash, gas, endowment, contractAddr)
}
// ChainConfig returns the environment's chain configuration
func (evm *EVM) ChainConfig() *params.ChainConfig { return evm.chainConfig }
func getTobinTax(evm *EVM, sender common.Address) (numerator *big.Int, denominator *big.Int, reserveAddress *common.Address, err error) {
reserveAddress, err = GetRegisteredAddressWithEvm(params.ReserveRegistryId, evm)
if err != nil {
return nil, nil, nil, err
}
ret, _, err := evm.Call(AccountRef(sender), *reserveAddress, params.TobinTaxFunctionSelector, params.MaxGasForGetOrComputeTobinTax, big.NewInt(0))
if err != nil {
return nil, nil, nil, err
}
// Expected size of ret is 64 bytes because getOrComputeTobinTax() returns two uint256 values,
// each of which is equivalent to 32 bytes
if binary.Size(ret) != 64 {
return nil, nil, nil, goerrors.New("Length of tobin tax not equal to 64 bytes")
}
numerator = new(big.Int).SetBytes(ret[0:32])
denominator = new(big.Int).SetBytes(ret[32:64])
if denominator.Cmp(common.Big0) == 0 {
return nil, nil, nil, goerrors.New("Tobin tax denominator equal to zero")
}
if numerator.Cmp(denominator) == 1 {
return nil, nil, nil, goerrors.New("Tobin tax numerator greater than denominator")
}
return numerator, denominator, reserveAddress, nil
}
// TobinTransfer performs a transfer that may take a tax from the sent amount and give it to the reserve.
// If the calculation or transfer of the tax amount fails for any reason, the regular transfer goes ahead.
// NB: Gas is not charged or accounted for this calculation.
func (evm *EVM) TobinTransfer(db StateDB, sender, recipient common.Address, gas uint64, amount *big.Int) (leftOverGas uint64, err error) {
// Run only primary evm.Call() with tracer
if evm.GetDebug() {
evm.SetDebug(false)
defer func() { evm.SetDebug(true) }()
}
if amount.Cmp(big.NewInt(0)) != 0 {
numerator, denominator, reserveAddress, err := getTobinTax(evm, sender)
if err == nil {
tobinTax := new(big.Int).Div(new(big.Int).Mul(numerator, amount), denominator)
evm.Context.Transfer(db, sender, recipient, new(big.Int).Sub(amount, tobinTax))
evm.Context.Transfer(db, sender, *reserveAddress, tobinTax)
return gas, nil
} else {
log.Error("Failed to get tobin tax", "error", err)
}
}
// Complete a normal transfer if the amount is 0 or the tobin tax value is unable to be fetched and parsed.
// We transfer even when the amount is 0 because state trie clearing [EIP161] is necessary at the end of a transaction
evm.Context.Transfer(db, sender, recipient, amount)
return gas, nil
}
func (evm *EVM) StaticCallFromSystem(contractAddress common.Address, abi abipkg.ABI, funcName string, args []interface{}, returnObj interface{}, gas uint64) (uint64, error) {
staticCall := func(transactionData []byte) ([]byte, uint64, error) {
return evm.StaticCall(systemCaller, contractAddress, transactionData, gas)
}
return evm.handleABICall(abi, funcName, args, returnObj, staticCall)
}
func (evm *EVM) CallFromSystem(contractAddress common.Address, abi abipkg.ABI, funcName string, args []interface{}, returnObj interface{}, gas uint64, value *big.Int) (uint64, error) {
call := func(transactionData []byte) ([]byte, uint64, error) {
return evm.Call(systemCaller, contractAddress, transactionData, gas, value)
}
return evm.handleABICall(abi, funcName, args, returnObj, call)
}
var (
errorSig = []byte{0x08, 0xc3, 0x79, 0xa0} // Keccak256("Error(string)")[:4]
abiString, _ = abipkg.NewType("string", "", nil)
)
func unpackError(result []byte) (string, error) {
if len(result) < 4 || !bytes.Equal(result[:4], errorSig) {
return "<tx result not Error(string)>", goerrors.New("TX result not of type Error(string)")
}
vs, err := abipkg.Arguments{{Type: abiString}}.UnpackValues(result[4:])
if err != nil {
return "<invalid tx result>", err
}
return vs[0].(string), nil
}
func (evm *EVM) handleABICall(abi abipkg.ABI, funcName string, args []interface{}, returnObj interface{}, call func([]byte) ([]byte, uint64, error)) (uint64, error) {
transactionData, err := abi.Pack(funcName, args...)
if err != nil {
log.Error("Error in generating the ABI encoding for the function call", "err", err, "funcName", funcName, "args", args)
return 0, err
}
ret, leftoverGas, err := call(transactionData)
if err != nil {
msg, _ := unpackError(ret)
// Do not log execution reverted as error for getAddressFor. This only happens before the Registry is deployed.
// TODO(nategraf): Find a more generic and complete solution to the problem of logging tolerated EVM call failures.
if funcName == "getAddressFor" {
log.Trace("Error in calling the EVM", "funcName", funcName, "transactionData", hexutil.Encode(transactionData), "err", err, "msg", msg)
} else {
log.Error("Error in calling the EVM", "funcName", funcName, "transactionData", hexutil.Encode(transactionData), "err", err, "msg", msg)
}
return leftoverGas, err
}
log.Trace("EVM call successful", "funcName", funcName, "transactionData", hexutil.Encode(transactionData), "ret", hexutil.Encode(ret))
if returnObj != nil {
if err := abi.Unpack(returnObj, funcName, ret); err != nil {
// TODO (mcortesi) Remove ErrEmptyArguments check after we change Proxy to fail on unset impl
// `ErrEmptyArguments` is expected when when syncing & importing blocks
// before a contract has been deployed
if err == abipkg.ErrEmptyArguments {
log.Trace("Error in unpacking EVM call return bytes", "err", err)
} else {
log.Error("Error in unpacking EVM call return bytes", "err", err)
}
return leftoverGas, err
}
}
return leftoverGas, nil
}