Merge branch 'split' into develop

This commit is contained in:
obscuren 2014-04-10 21:05:58 -04:00
commit 7d6ba88d2b
10 changed files with 178 additions and 165 deletions

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@ -12,7 +12,7 @@ type Callee interface {
Address() []byte Address() []byte
} }
type ClosureBody interface { type Reference interface {
Callee Callee
ethutil.RlpEncodable ethutil.RlpEncodable
GetMem(*big.Int) *ethutil.Value GetMem(*big.Int) *ethutil.Value
@ -22,7 +22,8 @@ type ClosureBody interface {
// Basic inline closure object which implement the 'closure' interface // Basic inline closure object which implement the 'closure' interface
type Closure struct { type Closure struct {
callee Callee callee Callee
object ClosureBody object Reference
Script []byte
State *State State *State
Gas *big.Int Gas *big.Int
@ -32,8 +33,8 @@ type Closure struct {
} }
// Create a new closure for the given data items // Create a new closure for the given data items
func NewClosure(callee Callee, object ClosureBody, state *State, gas, val *big.Int) *Closure { func NewClosure(callee Callee, object Reference, script []byte, state *State, gas, val *big.Int) *Closure {
return &Closure{callee, object, state, gas, val, nil} return &Closure{callee, object, script, state, gas, val, nil}
} }
// Retuns the x element in data slice // Retuns the x element in data slice
@ -46,6 +47,20 @@ func (c *Closure) GetMem(x *big.Int) *ethutil.Value {
return m return m
} }
func (c *Closure) Get(x *big.Int) *ethutil.Value {
return c.Gets(x, big.NewInt(1))
}
func (c *Closure) Gets(x, y *big.Int) *ethutil.Value {
if x.Int64() > int64(len(c.Script)) || y.Int64() > int64(len(c.Script)) {
return ethutil.NewValue(0)
}
partial := c.Script[x.Int64() : x.Int64()+y.Int64()]
return ethutil.NewValue(partial)
}
func (c *Closure) SetMem(x *big.Int, val *ethutil.Value) { func (c *Closure) SetMem(x *big.Int, val *ethutil.Value) {
c.object.SetMem(x, val) c.object.SetMem(x, val)
} }
@ -81,7 +96,7 @@ func (c *Closure) ReturnGas(gas *big.Int, state *State) {
c.Gas.Add(c.Gas, gas) c.Gas.Add(c.Gas, gas)
} }
func (c *Closure) Object() ClosureBody { func (c *Closure) Object() Reference {
return c.object return c.object
} }

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@ -9,8 +9,10 @@ type Contract struct {
Amount *big.Int Amount *big.Int
Nonce uint64 Nonce uint64
//state *ethutil.Trie //state *ethutil.Trie
state *State state *State
address []byte address []byte
script []byte
initScript []byte
} }
func NewContract(address []byte, Amount *big.Int, root []byte) *Contract { func NewContract(address []byte, Amount *big.Int, root []byte) *Contract {
@ -45,6 +47,14 @@ func (c *Contract) GetMem(num *big.Int) *ethutil.Value {
return c.Addr(nb) return c.Addr(nb)
} }
func (c *Contract) GetInstr(pc *big.Int) *ethutil.Value {
if int64(len(c.script)-1) < pc.Int64() {
return ethutil.NewValue(0)
}
return ethutil.NewValueFromBytes([]byte{c.script[pc.Int64()]})
}
func (c *Contract) SetMem(num *big.Int, val *ethutil.Value) { func (c *Contract) SetMem(num *big.Int, val *ethutil.Value) {
addr := ethutil.BigToBytes(num, 256) addr := ethutil.BigToBytes(num, 256)
c.state.trie.Update(string(addr), string(val.Encode())) c.state.trie.Update(string(addr), string(val.Encode()))
@ -60,7 +70,7 @@ func (c *Contract) Address() []byte {
} }
func (c *Contract) RlpEncode() []byte { func (c *Contract) RlpEncode() []byte {
return ethutil.Encode([]interface{}{c.Amount, c.Nonce, c.state.trie.Root}) return ethutil.Encode([]interface{}{c.Amount, c.Nonce, c.state.trie.Root, c.script, c.initScript})
} }
func (c *Contract) RlpDecode(data []byte) { func (c *Contract) RlpDecode(data []byte) {
@ -69,6 +79,8 @@ func (c *Contract) RlpDecode(data []byte) {
c.Amount = decoder.Get(0).BigInt() c.Amount = decoder.Get(0).BigInt()
c.Nonce = decoder.Get(1).Uint() c.Nonce = decoder.Get(1).Uint()
c.state = NewState(ethutil.NewTrie(ethutil.Config.Db, decoder.Get(2).Interface())) c.state = NewState(ethutil.NewTrie(ethutil.Config.Db, decoder.Get(2).Interface()))
c.script = decoder.Get(3).Bytes()
c.initScript = decoder.Get(4).Bytes()
} }
func MakeContract(tx *Transaction, state *State) *Contract { func MakeContract(tx *Transaction, state *State) *Contract {
@ -79,12 +91,17 @@ func MakeContract(tx *Transaction, state *State) *Contract {
value := tx.Value value := tx.Value
contract := NewContract(addr, value, []byte("")) contract := NewContract(addr, value, []byte(""))
state.trie.Update(string(addr), string(contract.RlpEncode())) state.trie.Update(string(addr), string(contract.RlpEncode()))
for i, val := range tx.Data { contract.script = tx.Data
if len(val) > 0 { contract.initScript = tx.Init
bytNum := ethutil.BigToBytes(big.NewInt(int64(i)), 256)
contract.state.trie.Update(string(bytNum), string(ethutil.Encode(val))) /*
for i, val := range tx.Data {
if len(val) > 0 {
bytNum := ethutil.BigToBytes(big.NewInt(int64(i)), 256)
contract.state.trie.Update(string(bytNum), string(ethutil.Encode(val)))
}
} }
} */
state.trie.Update(string(addr), string(contract.RlpEncode())) state.trie.Update(string(addr), string(contract.RlpEncode()))
return contract return contract

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@ -55,6 +55,7 @@ const (
// 0x50 range - 'storage' and execution // 0x50 range - 'storage' and execution
oPUSH = 0x50 oPUSH = 0x50
oPUSH20 = 0x80
oPOP = 0x51 oPOP = 0x51
oDUP = 0x52 oDUP = 0x52
oSWAP = 0x53 oSWAP = 0x53
@ -250,7 +251,7 @@ func (m *Memory) Print() {
if len(m.store) > 0 { if len(m.store) > 0 {
addr := 0 addr := 0
for i := 0; i+32 <= len(m.store); i += 32 { for i := 0; i+32 <= len(m.store); i += 32 {
fmt.Printf("%03d %v\n", addr, m.store[i:i+32]) fmt.Printf("%03d: % x\n", addr, m.store[i:i+32])
addr++ addr++
} }
} else { } else {

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@ -316,7 +316,7 @@ func (sm *StateManager) ProcessContract(contract *Contract, tx *Transaction, blo
}() }()
caller := sm.procState.GetAccount(tx.Sender()) caller := sm.procState.GetAccount(tx.Sender())
closure := NewClosure(caller, contract, sm.procState, tx.Gas, tx.Value) closure := NewClosure(caller, contract, contract.script, sm.procState, tx.Gas, tx.Value)
vm := NewVm(sm.procState, RuntimeVars{ vm := NewVm(sm.procState, RuntimeVars{
origin: caller.Address(), origin: caller.Address(),
blockNumber: block.BlockInfo().Number, blockNumber: block.BlockInfo().Number,

View File

@ -14,7 +14,8 @@ type Transaction struct {
Value *big.Int Value *big.Int
Gas *big.Int Gas *big.Int
Gasprice *big.Int Gasprice *big.Int
Data []string Data []byte
Init []byte
v byte v byte
r, s []byte r, s []byte
@ -22,11 +23,11 @@ type Transaction struct {
contractCreation bool contractCreation bool
} }
func NewContractCreationTx(value, gasprice *big.Int, data []string) *Transaction { func NewContractCreationTx(value, gasprice *big.Int, data []byte) *Transaction {
return &Transaction{Value: value, Gasprice: gasprice, Data: data, contractCreation: true} return &Transaction{Value: value, Gasprice: gasprice, Data: data, contractCreation: true}
} }
func NewTransactionMessage(to []byte, value, gasprice, gas *big.Int, data []string) *Transaction { func NewTransactionMessage(to []byte, value, gasprice, gas *big.Int, data []byte) *Transaction {
return &Transaction{Recipient: to, Value: value, Gasprice: gasprice, Gas: gas, Data: data} return &Transaction{Recipient: to, Value: value, Gasprice: gasprice, Gas: gas, Data: data}
} }
@ -45,19 +46,12 @@ func NewTransactionFromValue(val *ethutil.Value) *Transaction {
} }
func (tx *Transaction) Hash() []byte { func (tx *Transaction) Hash() []byte {
data := make([]interface{}, len(tx.Data)) data := []interface{}{tx.Nonce, tx.Value, tx.Gasprice, tx.Gas, tx.Recipient, string(tx.Data)}
for i, val := range tx.Data { if tx.contractCreation {
data[i] = val data = append(data, string(tx.Init))
} }
preEnc := []interface{}{ return ethutil.Sha3Bin(ethutil.NewValue(data).Encode())
tx.Nonce,
tx.Recipient,
tx.Value,
data,
}
return ethutil.Sha3Bin(ethutil.Encode(preEnc))
} }
func (tx *Transaction) IsContract() bool { func (tx *Transaction) IsContract() bool {
@ -110,15 +104,17 @@ func (tx *Transaction) Sign(privk []byte) error {
return nil return nil
} }
// [ NONCE, VALUE, GASPRICE, GAS, TO, DATA, V, R, S ]
// [ NONCE, VALUE, GASPRICE, GAS, 0, CODE, INIT, V, R, S ]
func (tx *Transaction) RlpData() interface{} { func (tx *Transaction) RlpData() interface{} {
data := []interface{}{tx.Nonce, tx.Value, tx.Gasprice} data := []interface{}{tx.Nonce, tx.Value, tx.Gasprice, tx.Gas, tx.Recipient, tx.Data}
if !tx.contractCreation { if tx.contractCreation {
data = append(data, tx.Recipient, tx.Gas) data = append(data, tx.Init)
} }
d := ethutil.NewSliceValue(tx.Data).Slice() //d := ethutil.NewSliceValue(tx.Data).Slice()
return append(data, d, tx.v, tx.r, tx.s) return append(data, tx.v, tx.r, tx.s)
} }
func (tx *Transaction) RlpValue() *ethutil.Value { func (tx *Transaction) RlpValue() *ethutil.Value {
@ -137,31 +133,19 @@ func (tx *Transaction) RlpValueDecode(decoder *ethutil.Value) {
tx.Nonce = decoder.Get(0).Uint() tx.Nonce = decoder.Get(0).Uint()
tx.Value = decoder.Get(1).BigInt() tx.Value = decoder.Get(1).BigInt()
tx.Gasprice = decoder.Get(2).BigInt() tx.Gasprice = decoder.Get(2).BigInt()
tx.Gas = decoder.Get(3).BigInt()
tx.Recipient = decoder.Get(4).Bytes()
tx.Data = decoder.Get(5).Bytes()
// If the 4th item is a list(slice) this tx // If the list is of length 10 it's a contract creation tx
// is a contract creation tx if decoder.Len() == 10 {
if decoder.Get(3).IsList() {
d := decoder.Get(3)
tx.Data = make([]string, d.Len())
for i := 0; i < d.Len(); i++ {
tx.Data[i] = d.Get(i).Str()
}
tx.v = byte(decoder.Get(4).Uint())
tx.r = decoder.Get(5).Bytes()
tx.s = decoder.Get(6).Bytes()
tx.contractCreation = true tx.contractCreation = true
tx.Init = decoder.Get(6).Bytes()
tx.v = byte(decoder.Get(7).Uint())
tx.r = decoder.Get(8).Bytes()
tx.s = decoder.Get(9).Bytes()
} else { } else {
tx.Recipient = decoder.Get(3).Bytes()
tx.Gas = decoder.Get(4).BigInt()
d := decoder.Get(5)
tx.Data = make([]string, d.Len())
for i := 0; i < d.Len(); i++ {
tx.Data[i] = d.Get(i).Str()
}
tx.v = byte(decoder.Get(6).Uint()) tx.v = byte(decoder.Get(6).Uint())
tx.r = decoder.Get(7).Bytes() tx.r = decoder.Get(7).Bytes()
tx.s = decoder.Get(8).Bytes() tx.s = decoder.Get(8).Bytes()

View File

@ -1,54 +1 @@
package ethchain package ethchain
import (
"encoding/hex"
"math/big"
"testing"
)
func TestAddressRetrieval(t *testing.T) {
// TODO
// 88f9b82462f6c4bf4a0fb15e5c3971559a316e7f
key, _ := hex.DecodeString("3ecb44df2159c26e0f995712d4f39b6f6e499b40749b1cf1246c37f9516cb6a4")
tx := &Transaction{
Nonce: 0,
Recipient: ZeroHash160,
Value: big.NewInt(0),
Data: nil,
}
//fmt.Printf("rlp %x\n", tx.RlpEncode())
//fmt.Printf("sha rlp %x\n", tx.Hash())
tx.Sign(key)
//fmt.Printf("hex tx key %x\n", tx.PublicKey())
//fmt.Printf("seder %x\n", tx.Sender())
}
func TestAddressRetrieval2(t *testing.T) {
// TODO
// 88f9b82462f6c4bf4a0fb15e5c3971559a316e7f
key, _ := hex.DecodeString("3ecb44df2159c26e0f995712d4f39b6f6e499b40749b1cf1246c37f9516cb6a4")
addr, _ := hex.DecodeString("944400f4b88ac9589a0f17ed4671da26bddb668b")
tx := &Transaction{
Nonce: 0,
Recipient: addr,
Value: big.NewInt(1000),
Data: nil,
}
tx.Sign(key)
//data, _ := hex.DecodeString("f85d8094944400f4b88ac9589a0f17ed4671da26bddb668b8203e8c01ca0363b2a410de00bc89be40f468d16e70e543b72191fbd8a684a7c5bef51dc451fa02d8ecf40b68f9c64ed623f6ee24c9c878943b812e1e76bd73ccb2bfef65579e7")
//tx := NewTransactionFromData(data)
/*
fmt.Println(tx.RlpValue())
fmt.Printf("rlp %x\n", tx.RlpEncode())
fmt.Printf("sha rlp %x\n", tx.Hash())
//tx.Sign(key)
fmt.Printf("hex tx key %x\n", tx.PublicKey())
fmt.Printf("seder %x\n", tx.Sender())
*/
}

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@ -2,7 +2,7 @@ package ethchain
import ( import (
_ "bytes" _ "bytes"
"fmt" _ "fmt"
"github.com/ethereum/eth-go/ethutil" "github.com/ethereum/eth-go/ethutil"
_ "github.com/obscuren/secp256k1-go" _ "github.com/obscuren/secp256k1-go"
_ "math" _ "math"
@ -72,7 +72,7 @@ func (vm *Vm) RunClosure(closure *Closure) []byte {
for { for {
step++ step++
// Get the memory location of pc // Get the memory location of pc
val := closure.GetMem(pc) val := closure.Get(pc)
// Get the opcode (it must be an opcode!) // Get the opcode (it must be an opcode!)
op := OpCode(val.Uint()) op := OpCode(val.Uint())
if ethutil.Config.Debug { if ethutil.Config.Debug {
@ -233,13 +233,37 @@ func (vm *Vm) RunClosure(closure *Closure) []byte {
// 0x10 range // 0x10 range
case oAND: case oAND:
x, y := stack.Popn()
if (x.Cmp(ethutil.BigTrue) >= 0) && (y.Cmp(ethutil.BigTrue) >= 0) {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case oOR: case oOR:
x, y := stack.Popn()
if (x.Cmp(ethutil.BigInt0) >= 0) || (y.Cmp(ethutil.BigInt0) >= 0) {
stack.Push(ethutil.BigTrue)
} else {
stack.Push(ethutil.BigFalse)
}
case oXOR: case oXOR:
x, y := stack.Popn()
stack.Push(base.Xor(x, y))
case oBYTE: case oBYTE:
val, th := stack.Popn()
if th.Cmp(big.NewInt(32)) < 0 {
stack.Push(big.NewInt(int64(len(val.Bytes())-1) - th.Int64()))
} else {
stack.Push(ethutil.BigFalse)
}
// 0x20 range // 0x20 range
case oSHA3: case oSHA3:
size, offset := stack.Popn()
data := mem.Get(offset.Int64(), size.Int64())
stack.Push(ethutil.BigD(data))
// 0x30 range // 0x30 range
case oADDRESS: case oADDRESS:
stack.Push(ethutil.BigD(closure.Object().Address())) stack.Push(ethutil.BigD(closure.Object().Address()))
@ -277,9 +301,23 @@ func (vm *Vm) RunClosure(closure *Closure) []byte {
// 0x50 range // 0x50 range
case oPUSH: // Push PC+1 on to the stack case oPUSH: // Push PC+1 on to the stack
pc.Add(pc, ethutil.Big1) pc.Add(pc, ethutil.Big1)
data := closure.Gets(pc, big.NewInt(32))
val := ethutil.BigD(data.Bytes())
val := closure.GetMem(pc).BigInt() // Push value to stack
stack.Push(val) stack.Push(val)
pc.Add(pc, big.NewInt(31))
case oPUSH20:
pc.Add(pc, ethutil.Big1)
data := closure.Gets(pc, big.NewInt(20))
val := ethutil.BigD(data.Bytes())
// Push value to stack
stack.Push(val)
pc.Add(pc, big.NewInt(19))
case oPOP: case oPOP:
stack.Pop() stack.Pop()
case oDUP: case oDUP:
@ -319,21 +357,20 @@ func (vm *Vm) RunClosure(closure *Closure) []byte {
stack.Push(big.NewInt(int64(mem.Len()))) stack.Push(big.NewInt(int64(mem.Len())))
// 0x60 range // 0x60 range
case oCALL: case oCALL:
// Pop return size and offset
retSize, retOffset := stack.Popn()
// Pop input size and offset
inSize, inOffset := stack.Popn()
fmt.Println(inSize, inOffset)
// Get the arguments from the memory
args := mem.Get(inOffset.Int64(), inSize.Int64())
// Pop gas and value of the stack.
gas, value := stack.Popn()
// Closure addr // Closure addr
addr := stack.Pop() addr := stack.Pop()
// Pop gas and value of the stack.
gas, value := stack.Popn()
// Pop input size and offset
inSize, inOffset := stack.Popn()
// Pop return size and offset
retSize, retOffset := stack.Popn()
// Get the arguments from the memory
args := mem.Get(inOffset.Int64(), inSize.Int64())
// Fetch the contract which will serve as the closure body // Fetch the contract which will serve as the closure body
contract := vm.state.GetContract(addr.Bytes()) contract := vm.state.GetContract(addr.Bytes())
// Create a new callable closure // Create a new callable closure
closure := NewClosure(closure, contract, vm.state, gas, value) closure := NewClosure(closure, contract, contract.script, vm.state, gas, value)
// Executer the closure and get the return value (if any) // Executer the closure and get the return value (if any)
ret := closure.Call(vm, args) ret := closure.Call(vm, args)
@ -361,7 +398,9 @@ func (vm *Vm) RunClosure(closure *Closure) []byte {
break out break out
*/ */
default: default:
ethutil.Config.Log.Debugln("Invalid opcode", op) ethutil.Config.Log.Debugf("Invalid opcode %x\n", op)
return closure.Return(nil)
} }
pc.Add(pc, ethutil.Big1) pc.Add(pc, ethutil.Big1)

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@ -84,27 +84,41 @@ func TestRun4(t *testing.T) {
asm, err := mutan.Compile(strings.NewReader(` asm, err := mutan.Compile(strings.NewReader(`
int32 a = 10 int32 a = 10
int32 b = 10 int32 b = 20
if a == b { if a > b {
int32 c = 10 int32 c = this.caller()
if c == 10 { }
int32 d = 1000 exit()
int32 e = 10 `), false)
} script := ethutil.Assemble(asm...)
tx := NewContractCreationTx(ethutil.Big("0"), ethutil.Big("1000"), script)
addr := tx.Hash()[12:]
contract := MakeContract(tx, state)
state.UpdateContract(contract)
fmt.Printf("%x\n", addr)
asm, err = mutan.Compile(strings.NewReader(`
// Check if there's any cash in the initial store
if store[1000] == 0 {
store[1000] = 10^20
} }
store[0] = 20 store[1001] = this.value() * 20
store[a] = 20 store[this.origin()] = store[this.origin()] + 1000
store[b] = this.caller()
int8[10] ret if store[1001] > 20 {
int8[10] arg store[1001] = 10^50
call(1234, 0, 100000000, arg, ret) }
int8 ret = 0
int8 arg = 10
store[1002] = "a46df28529eb8aa8b8c025b0b413c5f4b688352f"
call(store[1002], 0, 100000000, arg, ret)
`), false) `), false)
if err != nil { if err != nil {
fmt.Println(err) fmt.Println(err)
} }
//asm = append(asm, "LOG") asm = append(asm, "LOG")
fmt.Println(asm) fmt.Println(asm)
callerScript := ethutil.Assemble(asm...) callerScript := ethutil.Assemble(asm...)
@ -112,7 +126,8 @@ func TestRun4(t *testing.T) {
// Contract addr as test address // Contract addr as test address
account := NewAccount(ContractAddr, big.NewInt(10000000)) account := NewAccount(ContractAddr, big.NewInt(10000000))
callerClosure := NewClosure(account, MakeContract(callerTx, state), state, big.NewInt(1000000000), new(big.Int)) c := MakeContract(callerTx, state)
callerClosure := NewClosure(account, c, c.script, state, big.NewInt(1000000000), new(big.Int))
vm := NewVm(state, RuntimeVars{ vm := NewVm(state, RuntimeVars{
origin: account.Address(), origin: account.Address(),

View File

@ -1,8 +1,8 @@
package ethutil package ethutil
import ( import (
_ "fmt"
"math/big" "math/big"
"strconv"
) )
// Op codes // Op codes
@ -51,7 +51,10 @@ var OpCodes = map[string]byte{
"GASLIMIT": 0x45, "GASLIMIT": 0x45,
// 0x50 range - 'storage' and execution // 0x50 range - 'storage' and execution
"PUSH": 0x50, "PUSH": 0x50,
"PUSH20": 0x80,
"POP": 0x51, "POP": 0x51,
"DUP": 0x52, "DUP": 0x52,
"SWAP": 0x53, "SWAP": 0x53,
@ -98,11 +101,16 @@ func CompileInstr(s interface{}) ([]byte, error) {
// Assume regular bytes during compilation // Assume regular bytes during compilation
if !success { if !success {
num.SetBytes([]byte(str)) num.SetBytes([]byte(str))
} else {
// tmp fix for 32 bytes
n := BigToBytes(num, 256)
return n, nil
} }
return num.Bytes(), nil return num.Bytes(), nil
case int: case int:
return big.NewInt(int64(s.(int))).Bytes(), nil num := BigToBytes(big.NewInt(int64(s.(int))), 256)
return num, nil
case []byte: case []byte:
return BigD(s.([]byte)).Bytes(), nil return BigD(s.([]byte)).Bytes(), nil
} }
@ -110,34 +118,16 @@ func CompileInstr(s interface{}) ([]byte, error) {
return nil, nil return nil, nil
} }
func Instr(instr string) (int, []string, error) {
base := new(big.Int)
base.SetString(instr, 0)
args := make([]string, 7)
for i := 0; i < 7; i++ {
// int(int(val) / int(math.Pow(256,float64(i)))) % 256
exp := BigPow(256, i)
num := new(big.Int)
num.Div(base, exp)
args[i] = num.Mod(num, big.NewInt(256)).String()
}
op, _ := strconv.Atoi(args[0])
return op, args[1:7], nil
}
// Script compilation functions // Script compilation functions
// Compiles strings to machine code // Compiles strings to machine code
func Assemble(instructions ...interface{}) (script []string) { func Assemble(instructions ...interface{}) (script []byte) {
script = make([]string, len(instructions)) //script = make([]string, len(instructions))
for i, val := range instructions { for _, val := range instructions {
instr, _ := CompileInstr(val) instr, _ := CompileInstr(val)
script[i] = string(instr) //script[i] = string(instr)
script = append(script, instr...)
} }
return return

View File

@ -186,7 +186,12 @@ func Encode(object interface{}) []byte {
case byte: case byte:
buff.Write(Encode(big.NewInt(int64(t)))) buff.Write(Encode(big.NewInt(int64(t))))
case *big.Int: case *big.Int:
buff.Write(Encode(t.Bytes())) // Not sure how this is possible while we check for
if t == nil {
buff.WriteByte(0xc0)
} else {
buff.Write(Encode(t.Bytes()))
}
case []byte: case []byte:
if len(t) == 1 && t[0] <= 0x7f { if len(t) == 1 && t[0] <= 0x7f {
buff.Write(t) buff.Write(t)