core: vm: vm interface (#164)

1 files changed, 105 insertions, 0 deletions

diff --git a/core/vm/vm.go b/core/vm/vm.go
new file mode 100644
index 000000000..8d4dffd0b
--- /dev/null
+++ b/core/vm/vm.go
@@ -0,0 +1,105 @@
+package vm
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/dexon-foundation/dexon/common"
+)
+
+const (
+	EVM = byte(iota)
+	SQLVM
+)
+
+var (
+	MULTIVM = true
+)
+
+type VM interface {
+	Create(ContractRef, []byte, uint64, *big.Int,
+		Interpreter) ([]byte, common.Address, uint64, error)
+	Create2(ContractRef, []byte, uint64, *big.Int, *big.Int,
+		Interpreter) ([]byte, common.Address, uint64, error)
+	Call(ContractRef, common.Address, []byte, uint64, *big.Int,
+		Interpreter) ([]byte, uint64, error)
+	CallCode(ContractRef, common.Address, []byte, uint64,
+		*big.Int, Interpreter) ([]byte, uint64, error)
+	DelegateCall(ContractRef, common.Address, []byte, uint64,
+		Interpreter) ([]byte, uint64, error)
+	StaticCall(ContractRef, common.Address, []byte, uint64,
+		Interpreter) ([]byte, uint64, error)
+}
+
+type Interpreter interface {
+	StateDB() StateDB
+}
+
+var vmList map[byte]VM
+
+func init() {
+	vmList = make(map[byte]VM)
+}
+func Register(vmType byte, vm VM) {
+	vmList[vmType] = vm
+}
+func Create(caller ContractRef, code []byte, gas uint64, value *big.Int,
+	interpreter Interpreter) (ret []byte, contractAddr common.Address,
+	leftOverGas uint64, err error) {
+
+	name, code := getVMAndCode(code)
+	return vmList[name].Create(caller, code, gas, value, interpreter)
+}
+
+func Create2(caller ContractRef, code []byte, gas uint64, endowment *big.Int,
+	salt *big.Int, interpreter Interpreter) (ret []byte,
+	contractAddr common.Address, leftOverGas uint64, err error) {
+
+	name, code := getVMAndCode(code)
+	return vmList[name].Create2(caller, code, gas, endowment, salt, interpreter)
+}
+
+func Call(caller ContractRef, addr common.Address, input []byte, gas uint64,
+	value *big.Int, interpreter Interpreter) (ret []byte, leftOverGas uint64, err error) {
+
+	code := interpreter.StateDB().GetCode(addr)
+	name, _ := getVMAndCode(code)
+	return vmList[name].Call(caller, addr, input, gas, value, interpreter)
+}
+
+func CallCode(caller ContractRef, addr common.Address, input []byte, gas uint64,
+	value *big.Int, interpreter Interpreter) (ret []byte, leftOverGas uint64, err error) {
+
+	code := interpreter.StateDB().GetCode(addr)
+	name, _ := getVMAndCode(code)
+	return vmList[name].CallCode(caller, addr, input, gas, value, interpreter)
+}
+
+func DelegateCall(caller ContractRef, addr common.Address, input []byte,
+	gas uint64, interpreter Interpreter) (ret []byte, leftOverGas uint64, err error) {
+
+	code := interpreter.StateDB().GetCode(addr)
+	name, _ := getVMAndCode(code)
+	return vmList[name].DelegateCall(caller, addr, input, gas, interpreter)
+}
+
+func StaticCall(caller ContractRef, addr common.Address, input []byte,
+	gas uint64, interpreter Interpreter) (ret []byte, leftOverGas uint64, err error) {
+
+	code := interpreter.StateDB().GetCode(addr)
+	name, _ := getVMAndCode(code)
+	return vmList[name].StaticCall(caller, addr, input, gas, interpreter)
+}
+
+func getVMAndCode(code []byte) (byte, []byte) {
+	if MULTIVM && len(code) > 0 {
+		switch code[0] {
+		case EVM, SQLVM:
+			return code[0], code[1:]
+		default:
+			fmt.Printf("Unknow code prefix %x\n", code[0])
+			return EVM, code[1:]
+		}
+	}
+	return EVM, code
+}