core, core/vm: review changed from #3348

core/state_transition.go

@@ -159,7 +159,7 @@ func (self *StateTransition) to() vm.Account {
 
 func (self *StateTransition) useGas(amount *big.Int) error {
 	if self.gas.Cmp(amount) < 0 {
-		return vm.OutOfGasError
+		return vm.ErrOutOfGas
 	}
 	self.gas.Sub(self.gas, amount)
 
@@ -233,7 +233,7 @@ func (self *StateTransition) TransitionDb() (ret []byte, requiredGas, usedGas *b
 	)
 	if contractCreation {
 		ret, _, vmerr = vmenv.Create(sender, self.data, self.gas, self.value)
-		if homestead && err == vm.CodeStoreOutOfGasError {
+		if homestead && err == vm.ErrCodeStoreOutOfGas {
 			self.gas = Big0
 		}
 	} else {

core/vm/contracts.go

@@ -50,7 +50,7 @@ func RunPrecompiledContract(p PrecompiledContract, input []byte, contract *Contr
 
 		return ret, nil
 	} else {
-		return nil, OutOfGasError
+		return nil, ErrOutOfGas
 	}
 }
 

core/vm/environment.go

@@ -100,7 +100,7 @@ func (env *Environment) Call(caller ContractRef, addr common.Address, input []by
 	if env.Depth > int(params.CallCreateDepth.Int64()) {
 		caller.ReturnGas(gas)
 
-		return nil, DepthError
+		return nil, ErrDepth
 	}
 	if !env.Context.CanTransfer(env.StateDB, caller.Address(), value) {
 		caller.ReturnGas(gas)
@@ -110,7 +110,7 @@ func (env *Environment) Call(caller ContractRef, addr common.Address, input []by
 
 	var (
 		to       Account
-		snapshotPreTransfer = env.StateDB.Snapshot()
+		snapshot = env.StateDB.Snapshot()
 	)
 	if !env.StateDB.Exist(addr) {
 		if PrecompiledContracts[addr] == nil && env.ChainConfig().IsEIP158(env.BlockNumber) && value.BitLen() == 0 {
@@ -138,7 +138,7 @@ func (env *Environment) Call(caller ContractRef, addr common.Address, input []by
 	if err != nil {
 		contract.UseGas(contract.Gas)
 
-		env.StateDB.RevertToSnapshot(snapshotPreTransfer)
+		env.StateDB.RevertToSnapshot(snapshot)
 	}
 	return ret, err
 }
@@ -160,7 +160,7 @@ func (env *Environment) CallCode(caller ContractRef, addr common.Address, input
 	if env.Depth > int(params.CallCreateDepth.Int64()) {
 		caller.ReturnGas(gas)
 
-		return nil, DepthError
+		return nil, ErrDepth
 	}
 	if !env.CanTransfer(env.StateDB, caller.Address(), value) {
 		caller.ReturnGas(gas)
@@ -169,7 +169,7 @@ func (env *Environment) CallCode(caller ContractRef, addr common.Address, input
 	}
 
 	var (
-		snapshotPreTransfer = env.StateDB.Snapshot()
+		snapshot = env.StateDB.Snapshot()
 		to       = env.StateDB.GetAccount(caller.Address())
 	)
 	// initialise a new contract and set the code that is to be used by the
@@ -183,7 +183,7 @@ func (env *Environment) CallCode(caller ContractRef, addr common.Address, input
 	if err != nil {
 		contract.UseGas(contract.Gas)
 
-		env.StateDB.RevertToSnapshot(snapshotPreTransfer)
+		env.StateDB.RevertToSnapshot(snapshot)
 	}
 
 	return ret, err
@@ -205,7 +205,7 @@ func (env *Environment) DelegateCall(caller ContractRef, addr common.Address, in
 	// limit.
 	if env.Depth > int(params.CallCreateDepth.Int64()) {
 		caller.ReturnGas(gas)
-		return nil, DepthError
+		return nil, ErrDepth
 	}
 
 	var (
@@ -241,7 +241,7 @@ func (env *Environment) Create(caller ContractRef, code []byte, gas, value *big.
 	if env.Depth > int(params.CallCreateDepth.Int64()) {
 		caller.ReturnGas(gas)
 
-		return nil, common.Address{}, DepthError
+		return nil, common.Address{}, ErrDepth
 	}
 	if !env.CanTransfer(env.StateDB, caller.Address(), value) {
 		caller.ReturnGas(gas)
@@ -253,7 +253,7 @@ func (env *Environment) Create(caller ContractRef, code []byte, gas, value *big.
 	nonce := env.StateDB.GetNonce(caller.Address())
 	env.StateDB.SetNonce(caller.Address(), nonce+1)
 
-	snapshotPreTransfer := env.StateDB.Snapshot()
+	snapshot := env.StateDB.Snapshot()
 	var (
 		addr = crypto.CreateAddress(caller.Address(), nonce)
 		to   = env.StateDB.CreateAccount(addr)
@@ -283,7 +283,7 @@ func (env *Environment) Create(caller ContractRef, code []byte, gas, value *big.
 		if contract.UseGas(dataGas) {
 			env.StateDB.SetCode(addr, ret)
 		} else {
-			err = CodeStoreOutOfGasError
+			err = ErrCodeStoreOutOfGas
 		}
 	}
 
@@ -291,9 +291,9 @@ func (env *Environment) Create(caller ContractRef, code []byte, gas, value *big.
 	// 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 && (env.ChainConfig().IsHomestead(env.BlockNumber) || err != CodeStoreOutOfGasError)) {
+		(err != nil && (env.ChainConfig().IsHomestead(env.BlockNumber) || err != ErrCodeStoreOutOfGas)) {
 		contract.UseGas(contract.Gas)
-		env.StateDB.RevertToSnapshot(snapshotPreTransfer)
+		env.StateDB.RevertToSnapshot(snapshot)
 
 		// Nothing should be returned when an error is thrown.
 		return nil, addr, err

core/vm/errors.go

@@ -16,17 +16,12 @@
 
 package vm
 
-import (
+import "errors"
-	"errors"
-	"fmt"
-
-	"github.com/ethereum/go-ethereum/params"
-)
 
 var (
-	OutOfGasError          = errors.New("Out of gas")
+	ErrOutOfGas            = errors.New("out of gas")
-	CodeStoreOutOfGasError = errors.New("Contract creation code storage out of gas")
+	ErrCodeStoreOutOfGas   = errors.New("contract creation code storage out of gas")
-	DepthError             = fmt.Errorf("Max call depth exceeded (%d)", params.CallCreateDepth)
+	ErrDepth               = errors.New("max call depth exceeded")
-	TraceLimitReachedError = errors.New("The number of logs reached the specified limit")
+	ErrTraceLimitReached   = errors.New("the number of logs reached the specified limit")
 	ErrInsufficientBalance = errors.New("insufficient balance for transfer")
 )

core/vm/instructions.go

@@ -478,9 +478,9 @@ func opCreate(pc *uint64, env *Environment, contract *Contract, memory *Memory,
 	// homestead we must check for CodeStoreOutOfGasError (homestead only
 	// rule) and treat as an error, if the ruleset is frontier we must
 	// ignore this error and pretend the operation was successful.
-	if env.ChainConfig().IsHomestead(env.BlockNumber) && suberr == CodeStoreOutOfGasError {
+	if env.ChainConfig().IsHomestead(env.BlockNumber) && suberr == ErrCodeStoreOutOfGas {
 		stack.push(new(big.Int))
-	} else if suberr != nil && suberr != CodeStoreOutOfGasError {
+	} else if suberr != nil && suberr != ErrCodeStoreOutOfGas {
 		stack.push(new(big.Int))
 	} else {
 		stack.push(addr.Big())

core/vm/logger.go

@@ -97,7 +97,7 @@ func NewStructLogger(cfg *LogConfig) *StructLogger {
 func (l *StructLogger) CaptureState(env *Environment, pc uint64, op OpCode, gas, cost *big.Int, memory *Memory, stack *Stack, contract *Contract, depth int, err error) error {
 	// check if already accumulated the specified number of logs
 	if l.cfg.Limit != 0 && l.cfg.Limit <= len(l.logs) {
-		return TraceLimitReachedError
+		return ErrTraceLimitReached
 	}
 
 	// initialise new changed values storage container for this contract

core/vm/vm.go

@@ -168,7 +168,7 @@ func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) {
 			// cost is explicitly set so that the capture state defer method cas get the proper cost
 			cost = operation.gasCost(evm.gasTable, evm.env, contract, stack, mem, memorySize)
 			if !contract.UseGas(cost) {
-				return nil, OutOfGasError
+				return nil, ErrOutOfGas
 			}
 		}
 		if memorySize != nil {