core, core/vm: implemented a generic environment (#3348)

Environment is now a struct (not an interface). This
reduces a lot of tech-debt throughout the codebase where a virtual
machine environment had to be implemented in order to test or run it.

The new environment is suitable to be used en the json tests, core
consensus and light client.

1 files changed, 14 insertions, 84 deletions

diff --git a/core/vm/runtime/env.go b/core/vm/runtime/env.go
index f1a2b60d3..3cf0dd024 100644
--- a/core/vm/runtime/env.go
+++ b/core/vm/runtime/env.go
@@ -23,92 +23,22 @@ import (
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/state"
 	"github.com/ethereum/go-ethereum/core/vm"
-	"github.com/ethereum/go-ethereum/params"
 )
 
-// Env is a basic runtime environment required for running the EVM.
-type Env struct {
-	chainConfig *params.ChainConfig
-	depth       int
-	state       *state.StateDB
-
-	origin   common.Address
-	coinbase common.Address
-
-	number     *big.Int
-	time       *big.Int
-	difficulty *big.Int
-	gasLimit   *big.Int
-
-	getHashFn func(uint64) common.Hash
-
-	evm *vm.EVM
-}
-
-// NewEnv returns a new vm.Environment
-func NewEnv(cfg *Config, state *state.StateDB) vm.Environment {
-	env := &Env{
-		chainConfig: cfg.ChainConfig,
-		state:       state,
-		origin:      cfg.Origin,
-		coinbase:    cfg.Coinbase,
-		number:      cfg.BlockNumber,
-		time:        cfg.Time,
-		difficulty:  cfg.Difficulty,
-		gasLimit:    cfg.GasLimit,
+func NewEnv(cfg *Config, state *state.StateDB) *vm.Environment {
+	context := vm.Context{
+		CanTransfer: core.CanTransfer,
+		Transfer:    core.Transfer,
+		GetHash:     func(uint64) common.Hash { return common.Hash{} },
+
+		Origin:      cfg.Origin,
+		Coinbase:    cfg.Coinbase,
+		BlockNumber: cfg.BlockNumber,
+		Time:        cfg.Time,
+		Difficulty:  cfg.Difficulty,
+		GasLimit:    cfg.GasLimit,
+		GasPrice:    new(big.Int),
 	}
-	env.evm = vm.New(env, vm.Config{
-		Debug:     cfg.Debug,
-		EnableJit: !cfg.DisableJit,
-		ForceJit:  !cfg.DisableJit,
-	})
-
-	return env
-}
-
-func (self *Env) ChainConfig() *params.ChainConfig { return self.chainConfig }
-func (self *Env) Vm() vm.Vm                        { return self.evm }
-func (self *Env) Origin() common.Address           { return self.origin }
-func (self *Env) BlockNumber() *big.Int            { return self.number }
-func (self *Env) Coinbase() common.Address         { return self.coinbase }
-func (self *Env) Time() *big.Int                   { return self.time }
-func (self *Env) Difficulty() *big.Int             { return self.difficulty }
-func (self *Env) Db() vm.Database                  { return self.state }
-func (self *Env) GasLimit() *big.Int               { return self.gasLimit }
-func (self *Env) VmType() vm.Type                  { return vm.StdVmTy }
-func (self *Env) GetHash(n uint64) common.Hash {
-	return self.getHashFn(n)
-}
-func (self *Env) AddLog(log *vm.Log) {
-	self.state.AddLog(log)
-}
-func (self *Env) Depth() int     { return self.depth }
-func (self *Env) SetDepth(i int) { self.depth = i }
-func (self *Env) CanTransfer(from common.Address, balance *big.Int) bool {
-	return self.state.GetBalance(from).Cmp(balance) >= 0
-}
-func (self *Env) SnapshotDatabase() int {
-	return self.state.Snapshot()
-}
-func (self *Env) RevertToSnapshot(snapshot int) {
-	self.state.RevertToSnapshot(snapshot)
-}
-
-func (self *Env) Transfer(from, to vm.Account, amount *big.Int) {
-	core.Transfer(from, to, amount)
-}
-
-func (self *Env) Call(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
-	return core.Call(self, caller, addr, data, gas, price, value)
-}
-func (self *Env) CallCode(caller vm.ContractRef, addr common.Address, data []byte, gas, price, value *big.Int) ([]byte, error) {
-	return core.CallCode(self, caller, addr, data, gas, price, value)
-}
-
-func (self *Env) DelegateCall(me vm.ContractRef, addr common.Address, data []byte, gas, price *big.Int) ([]byte, error) {
-	return core.DelegateCall(self, me, addr, data, gas, price)
-}
 
-func (self *Env) Create(caller vm.ContractRef, data []byte, gas, price, value *big.Int) ([]byte, common.Address, error) {
-	return core.Create(self, caller, data, gas, price, value)
+	return vm.NewEnvironment(context, cfg.State, cfg.ChainConfig, cfg.EVMConfig)
 }