plugeth/core/vm/environment.go
Jeffrey Wilcke 342ae7ce7d core, core/vm, tests: changed the initialisation behaviour of the EVM
The EVM was previously initialised and created for every CALL, CALLCODE,
DELEGATECALL and CREATE. This PR changes this behaviour so that the same
EVM can be used through the session and beyond as long as the
Environment sticks around.
2016-03-23 00:04:00 +01:00

127 lines
3.9 KiB
Go

// 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"
)
// Environment is is required by the virtual machine to get information from
// it's own isolated environment.
// Environment is an EVM requirement and helper which allows access to outside
// information such as states.
type Environment interface {
// The state database
Db() Database
// Creates a restorable snapshot
MakeSnapshot() Database
// Set database to previous snapshot
SetSnapshot(Database)
// Address of the original invoker (first occurrence of the VM invoker)
Origin() common.Address
// The block number this VM is invoked on
BlockNumber() *big.Int
// The n'th hash ago from this block number
GetHash(uint64) common.Hash
// The handler's address
Coinbase() common.Address
// The current time (block time)
Time() *big.Int
// Difficulty set on the current block
Difficulty() *big.Int
// The gas limit of the block
GasLimit() *big.Int
// Determines whether it's possible to transact
CanTransfer(from common.Address, balance *big.Int) bool
// Transfers amount from one account to the other
Transfer(from, to Account, amount *big.Int)
// Adds a LOG to the state
AddLog(*Log)
// Adds a structured log to the env
AddStructLog(StructLog)
// Returns all coalesced structured logs
StructLogs() []StructLog
// Type of the VM
Vm() *Vm
// Current calling depth
Depth() int
SetDepth(i int)
// Call another contract
Call(me ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
// Take another's contract code and execute within our own context
CallCode(me ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error)
// Same as CallCode except sender and value is propagated from parent to child scope
DelegateCall(me ContractRef, addr common.Address, data []byte, gas, price *big.Int) ([]byte, error)
// Create a new contract
Create(me ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error)
}
// Database is a EVM database for full state querying
type Database interface {
GetAccount(common.Address) Account
CreateAccount(common.Address) Account
AddBalance(common.Address, *big.Int)
GetBalance(common.Address) *big.Int
GetNonce(common.Address) uint64
SetNonce(common.Address, uint64)
GetCode(common.Address) []byte
SetCode(common.Address, []byte)
AddRefund(*big.Int)
GetRefund() *big.Int
GetState(common.Address, common.Hash) common.Hash
SetState(common.Address, common.Hash, common.Hash)
Delete(common.Address) bool
Exist(common.Address) bool
IsDeleted(common.Address) bool
}
// StructLog is emitted to the Environment each cycle and lists information about the current internal state
// prior to the execution of the statement.
type StructLog struct {
Pc uint64
Op OpCode
Gas *big.Int
GasCost *big.Int
Memory []byte
Stack []*big.Int
Storage map[common.Hash][]byte
Err error
}
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, *big.Int)
SetCode([]byte)
EachStorage(cb func(key, value []byte))
Value() *big.Int
}