diff --git a/cmd/evm/main.go b/cmd/evm/main.go
index 7dd375b148..be6546c953 100644
--- a/cmd/evm/main.go
+++ b/cmd/evm/main.go
@@ -206,6 +206,9 @@ func (self *VMEnv) StructLogs() []vm.StructLog {
func (self *VMEnv) AddLog(log *state.Log) {
self.state.AddLog(log)
}
+func (self *VMEnv) CanTransfer(from vm.Account, balance *big.Int) bool {
+ return from.Balance().Cmp(balance) >= 0
+}
func (self *VMEnv) Transfer(from, to vm.Account, amount *big.Int) error {
return vm.Transfer(from, to, amount)
}
diff --git a/core/execution.go b/core/execution.go
index 699bad9a38..3a136515df 100644
--- a/core/execution.go
+++ b/core/execution.go
@@ -26,6 +26,7 @@ import (
"github.com/ethereum/go-ethereum/params"
)
+// Execution is the execution environment for the given call or create action.
type Execution struct {
env vm.Environment
address *common.Address
@@ -35,12 +36,15 @@ type Execution struct {
Gas, price, value *big.Int
}
+// NewExecution returns a new execution environment that handles all calling
+// and creation logic defined by the YP.
func NewExecution(env vm.Environment, address *common.Address, input []byte, gas, gasPrice, value *big.Int) *Execution {
exe := &Execution{env: env, address: address, input: input, Gas: gas, price: gasPrice, value: value}
exe.evm = vm.NewVm(env)
return exe
}
+// Call executes within the given context
func (self *Execution) Call(codeAddr common.Address, caller vm.ContextRef) ([]byte, error) {
// Retrieve the executing code
code := self.env.State().GetCode(codeAddr)
@@ -48,6 +52,9 @@ func (self *Execution) Call(codeAddr common.Address, caller vm.ContextRef) ([]by
return self.exec(&codeAddr, code, caller)
}
+// Create creates a new contract and runs the initialisation procedure of the
+// contract. This returns the returned code for the contract and is stored
+// elsewhere.
func (self *Execution) Create(caller vm.ContextRef) (ret []byte, err error, account *state.StateObject) {
// Input must be nil for create
code := self.input
@@ -63,16 +70,24 @@ func (self *Execution) Create(caller vm.ContextRef) (ret []byte, err error, acco
return
}
+// exec executes the given code and executes within the contextAddr context.
func (self *Execution) exec(contextAddr *common.Address, code []byte, caller vm.ContextRef) (ret []byte, err error) {
env := self.env
evm := self.evm
+ // Depth check execution. Fail if we're trying to execute above the
+ // limit.
if env.Depth() > int(params.CallCreateDepth.Int64()) {
caller.ReturnGas(self.Gas, self.price)
return nil, vm.DepthError
}
- vsnapshot := env.State().Copy()
+ if !env.CanTransfer(env.State().GetStateObject(caller.Address()), self.value) {
+ caller.ReturnGas(self.Gas, self.price)
+
+ return nil, ValueTransferErr("insufficient funds to transfer value. Req %v, has %v", self.value, env.State().GetBalance(caller.Address()))
+ }
+
var createAccount bool
if self.address == nil {
// Generate a new address
@@ -95,15 +110,7 @@ func (self *Execution) exec(contextAddr *common.Address, code []byte, caller vm.
} else {
to = env.State().GetOrNewStateObject(*self.address)
}
-
- err = env.Transfer(from, to, self.value)
- if err != nil {
- env.State().Set(vsnapshot)
-
- caller.ReturnGas(self.Gas, self.price)
-
- return nil, ValueTransferErr("insufficient funds to transfer value. Req %v, has %v", self.value, from.Balance())
- }
+ vm.Transfer(from, to, self.value)
context := vm.NewContext(caller, to, self.value, self.Gas, self.price)
context.SetCallCode(contextAddr, code)
diff --git a/core/vm/environment.go b/core/vm/environment.go
index 723924b6fc..5a1bf32010 100644
--- a/core/vm/environment.go
+++ b/core/vm/environment.go
@@ -36,6 +36,7 @@ type Environment interface {
Time() uint64
Difficulty() *big.Int
GasLimit() *big.Int
+ CanTransfer(from Account, balance *big.Int) bool
Transfer(from, to Account, amount *big.Int) error
AddLog(*state.Log)
AddStructLog(StructLog)
diff --git a/core/vm/instructions.go b/core/vm/instructions.go
index 7793ff1698..d7605e5a29 100644
--- a/core/vm/instructions.go
+++ b/core/vm/instructions.go
@@ -13,6 +13,7 @@
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see .
+
package vm
import (
diff --git a/core/vm/jit.go b/core/vm/jit.go
index a773092234..c66630ae83 100644
--- a/core/vm/jit.go
+++ b/core/vm/jit.go
@@ -13,6 +13,7 @@
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see .
+
package vm
import (
@@ -48,7 +49,7 @@ func SetJITCacheSize(size int) {
programs, _ = lru.New(size)
}
-// GetProgram returns the program by id or nil when non-existant
+// GetProgram returns the program by id or nil when non-existent
func GetProgram(id common.Hash) *Program {
if p, ok := programs.Get(id); ok {
return p.(*Program)
diff --git a/core/vm/jit_test.go b/core/vm/jit_test.go
index 70432d47b0..5b3feea992 100644
--- a/core/vm/jit_test.go
+++ b/core/vm/jit_test.go
@@ -105,6 +105,9 @@ func (self *Env) AddLog(log *state.Log) {
}
func (self *Env) Depth() int { return self.depth }
func (self *Env) SetDepth(i int) { self.depth = i }
+func (self *Env) CanTransfer(from Account, balance *big.Int) bool {
+ return from.Balance().Cmp(balance) >= 0
+}
func (self *Env) Transfer(from, to Account, amount *big.Int) error {
return nil
}
diff --git a/core/vm/settings.go b/core/vm/settings.go
index 9e30d3adde..b94efd9ab1 100644
--- a/core/vm/settings.go
+++ b/core/vm/settings.go
@@ -13,6 +13,7 @@
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see .
+
package vm
var (
diff --git a/core/vm_env.go b/core/vm_env.go
index c1a86d63e2..7198295437 100644
--- a/core/vm_env.go
+++ b/core/vm_env.go
@@ -69,6 +69,10 @@ func (self *VMEnv) GetHash(n uint64) common.Hash {
func (self *VMEnv) AddLog(log *state.Log) {
self.state.AddLog(log)
}
+func (self *VMEnv) CanTransfer(from vm.Account, balance *big.Int) bool {
+ return from.Balance().Cmp(balance) >= 0
+}
+
func (self *VMEnv) Transfer(from, to vm.Account, amount *big.Int) error {
return vm.Transfer(from, to, amount)
}
diff --git a/tests/util.go b/tests/util.go
index 6ee1a42db7..3b94effc8f 100644
--- a/tests/util.go
+++ b/tests/util.go
@@ -18,7 +18,6 @@ package tests
import (
"bytes"
- "errors"
"fmt"
"math/big"
@@ -192,18 +191,19 @@ func (self *Env) AddLog(log *state.Log) {
}
func (self *Env) Depth() int { return self.depth }
func (self *Env) SetDepth(i int) { self.depth = i }
-func (self *Env) Transfer(from, to vm.Account, amount *big.Int) error {
+func (self *Env) CanTransfer(from vm.Account, balance *big.Int) bool {
if self.skipTransfer {
- // ugly hack
if self.initial {
self.initial = false
- return nil
+ return true
}
+ }
- if from.Balance().Cmp(amount) < 0 {
- return errors.New("Insufficient balance in account")
- }
+ return from.Balance().Cmp(balance) >= 0
+}
+func (self *Env) Transfer(from, to vm.Account, amount *big.Int) error {
+ if self.skipTransfer {
return nil
}
return vm.Transfer(from, to, amount)