// 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 (
"math/big"
"github.com/ethereum/go-ethereum/common"
)
// StateDB is an EVM database for full state querying.
type StateDB interface {
GetAccount(common.Address) Account
CreateAccount(common.Address) Account
SubBalance(common.Address, *big.Int)
AddBalance(common.Address, *big.Int)
GetBalance(common.Address) *big.Int
GetNonce(common.Address) uint64
SetNonce(common.Address, uint64)
GetCodeHash(common.Address) common.Hash
GetCode(common.Address) []byte
SetCode(common.Address, []byte)
GetCodeSize(common.Address) int
AddRefund(*big.Int)
GetRefund() *big.Int
GetState(common.Address, common.Hash) common.Hash
SetState(common.Address, common.Hash, common.Hash)
Suicide(common.Address) bool
HasSuicided(common.Address) bool
// Exist reports whether the given account exists in state.
// Notably this should also return true for suicided accounts.
Exist(common.Address) bool
// Empty returns whether the given account is empty. Empty
// is defined according to EIP161 (balance = nonce = code = 0).
Empty(common.Address) bool
RevertToSnapshot(int)
Snapshot() int
AddLog(*Log)
}
// Account represents a contract or basic ethereum account.
type Account interface {
SubBalance(amount *big.Int)
AddBalance(amount *big.Int)
SetBalance(*big.Int)
SetNonce(uint64)
Balance() *big.Int
Address() common.Address
ReturnGas(*big.Int)
SetCode(common.Hash, []byte)
ForEachStorage(cb func(key, value common.Hash) bool)
Value() *big.Int
}
// CallContext provides a basic interface for the EVM calling conventions. The EVM EVM
// depends on this context being implemented for doing subcalls and initialising new EVM contracts.
type CallContext interface {
// Call another contract
Call(env *EVM, me ContractRef, addr common.Address, data []byte, gas, value *big.Int) ([]byte, error)
// Take another's contract code and execute within our own context
CallCode(env *EVM, me ContractRef, addr common.Address, data []byte, gas, value *big.Int) ([]byte, error)
// Same as CallCode except sender and value is propagated from parent to child scope
DelegateCall(env *EVM, me ContractRef, addr common.Address, data []byte, gas *big.Int) ([]byte, error)
// Create a new contract
Create(env *EVM, me ContractRef, data []byte, gas, value *big.Int) ([]byte, common.Address, error)
}