Merge pull request #15731 from holiman/revamp_abi

accounts/abi refactor
This commit is contained in:
Martin Holst Swende 2017-12-22 20:59:41 +01:00 committed by GitHub
commit 9d187f0238
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GPG Key ID: 4AEE18F83AFDEB23
11 changed files with 667 additions and 380 deletions

@ -17,6 +17,7 @@
package abi
import (
"bytes"
"encoding/json"
"fmt"
"io"
@ -50,25 +51,25 @@ func JSON(reader io.Reader) (ABI, error) {
// methods string signature. (signature = baz(uint32,string32))
func (abi ABI) Pack(name string, args ...interface{}) ([]byte, error) {
// Fetch the ABI of the requested method
var method Method
if name == "" {
method = abi.Constructor
} else {
m, exist := abi.Methods[name]
if !exist {
return nil, fmt.Errorf("method '%s' not found", name)
// constructor
arguments, err := abi.Constructor.Inputs.Pack(args...)
if err != nil {
return nil, err
}
method = m
return arguments, nil
}
arguments, err := method.pack(args...)
method, exist := abi.Methods[name]
if !exist {
return nil, fmt.Errorf("method '%s' not found", name)
}
arguments, err := method.Inputs.Pack(args...)
if err != nil {
return nil, err
}
// Pack up the method ID too if not a constructor and return
if name == "" {
return arguments, nil
}
return append(method.Id(), arguments...), nil
}
@ -77,28 +78,20 @@ func (abi ABI) Unpack(v interface{}, name string, output []byte) (err error) {
if len(output) == 0 {
return fmt.Errorf("abi: unmarshalling empty output")
}
// since there can't be naming collisions with contracts and events,
// we need to decide whether we're calling a method or an event
var unpack unpacker
if method, ok := abi.Methods[name]; ok {
if len(output)%32 != 0 {
return fmt.Errorf("abi: improperly formatted output")
}
unpack = method
return method.Outputs.Unpack(v, output)
} else if event, ok := abi.Events[name]; ok {
unpack = event
} else {
return fmt.Errorf("abi: could not locate named method or event.")
return event.Inputs.Unpack(v, output)
}
// requires a struct to unpack into for a tuple return...
if unpack.isTupleReturn() {
return unpack.tupleUnpack(v, output)
}
return unpack.singleUnpack(v, output)
return fmt.Errorf("abi: could not locate named method or event")
}
// UnmarshalJSON implements json.Unmarshaler interface
func (abi *ABI) UnmarshalJSON(data []byte) error {
var fields []struct {
Type string
@ -141,3 +134,14 @@ func (abi *ABI) UnmarshalJSON(data []byte) error {
return nil
}
// MethodById looks up a method by the 4-byte id
// returns nil if none found
func (abi *ABI) MethodById(sigdata []byte) *Method {
for _, method := range abi.Methods {
if bytes.Equal(method.Id(), sigdata[:4]) {
return &method
}
}
return nil
}

@ -22,10 +22,11 @@ import (
"fmt"
"log"
"math/big"
"reflect"
"strings"
"testing"
"reflect"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
)
@ -75,9 +76,24 @@ func TestReader(t *testing.T) {
}
// deep equal fails for some reason
t.Skip()
if !reflect.DeepEqual(abi, exp) {
t.Errorf("\nabi: %v\ndoes not match exp: %v", abi, exp)
for name, expM := range exp.Methods {
gotM, exist := abi.Methods[name]
if !exist {
t.Errorf("Missing expected method %v", name)
}
if !reflect.DeepEqual(gotM, expM) {
t.Errorf("\nGot abi method: \n%v\ndoes not match expected method\n%v", gotM, expM)
}
}
for name, gotM := range abi.Methods {
expM, exist := exp.Methods[name]
if !exist {
t.Errorf("Found extra method %v", name)
}
if !reflect.DeepEqual(gotM, expM) {
t.Errorf("\nGot abi method: \n%v\ndoes not match expected method\n%v", gotM, expM)
}
}
}
@ -641,3 +657,42 @@ func TestUnpackEvent(t *testing.T) {
t.Logf("len(data): %d; received event: %+v", len(data), ev)
}
}
func TestABI_MethodById(t *testing.T) {
const abiJSON = `[
{"type":"function","name":"receive","constant":false,"inputs":[{"name":"memo","type":"bytes"}],"outputs":[],"payable":true,"stateMutability":"payable"},
{"type":"event","name":"received","anonymous":false,"inputs":[{"indexed":false,"name":"sender","type":"address"},{"indexed":false,"name":"amount","type":"uint256"},{"indexed":false,"name":"memo","type":"bytes"}]},
{"type":"function","name":"fixedArrStr","constant":true,"inputs":[{"name":"str","type":"string"},{"name":"fixedArr","type":"uint256[2]"}]},
{"type":"function","name":"fixedArrBytes","constant":true,"inputs":[{"name":"str","type":"bytes"},{"name":"fixedArr","type":"uint256[2]"}]},
{"type":"function","name":"mixedArrStr","constant":true,"inputs":[{"name":"str","type":"string"},{"name":"fixedArr","type":"uint256[2]"},{"name":"dynArr","type":"uint256[]"}]},
{"type":"function","name":"doubleFixedArrStr","constant":true,"inputs":[{"name":"str","type":"string"},{"name":"fixedArr1","type":"uint256[2]"},{"name":"fixedArr2","type":"uint256[3]"}]},
{"type":"function","name":"multipleMixedArrStr","constant":true,"inputs":[{"name":"str","type":"string"},{"name":"fixedArr1","type":"uint256[2]"},{"name":"dynArr","type":"uint256[]"},{"name":"fixedArr2","type":"uint256[3]"}]},
{"type":"function","name":"balance","constant":true},
{"type":"function","name":"send","constant":false,"inputs":[{"name":"amount","type":"uint256"}]},
{"type":"function","name":"test","constant":false,"inputs":[{"name":"number","type":"uint32"}]},
{"type":"function","name":"string","constant":false,"inputs":[{"name":"inputs","type":"string"}]},
{"type":"function","name":"bool","constant":false,"inputs":[{"name":"inputs","type":"bool"}]},
{"type":"function","name":"address","constant":false,"inputs":[{"name":"inputs","type":"address"}]},
{"type":"function","name":"uint64[2]","constant":false,"inputs":[{"name":"inputs","type":"uint64[2]"}]},
{"type":"function","name":"uint64[]","constant":false,"inputs":[{"name":"inputs","type":"uint64[]"}]},
{"type":"function","name":"foo","constant":false,"inputs":[{"name":"inputs","type":"uint32"}]},
{"type":"function","name":"bar","constant":false,"inputs":[{"name":"inputs","type":"uint32"},{"name":"string","type":"uint16"}]},
{"type":"function","name":"_slice","constant":false,"inputs":[{"name":"inputs","type":"uint32[2]"}]},
{"type":"function","name":"__slice256","constant":false,"inputs":[{"name":"inputs","type":"uint256[2]"}]},
{"type":"function","name":"sliceAddress","constant":false,"inputs":[{"name":"inputs","type":"address[]"}]},
{"type":"function","name":"sliceMultiAddress","constant":false,"inputs":[{"name":"a","type":"address[]"},{"name":"b","type":"address[]"}]}
]
`
abi, err := JSON(strings.NewReader(abiJSON))
if err != nil {
t.Fatal(err)
}
for name, m := range abi.Methods {
a := fmt.Sprintf("%v", m)
b := fmt.Sprintf("%v", abi.MethodById(m.Id()))
if a != b {
t.Errorf("Method %v (id %v) not 'findable' by id in ABI", name, common.ToHex(m.Id()))
}
}
}

@ -19,6 +19,8 @@ package abi
import (
"encoding/json"
"fmt"
"reflect"
"strings"
)
// Argument holds the name of the argument and the corresponding type.
@ -29,7 +31,10 @@ type Argument struct {
Indexed bool // indexed is only used by events
}
func (a *Argument) UnmarshalJSON(data []byte) error {
type Arguments []Argument
// UnmarshalJSON implements json.Unmarshaler interface
func (argument *Argument) UnmarshalJSON(data []byte) error {
var extarg struct {
Name string
Type string
@ -40,12 +45,180 @@ func (a *Argument) UnmarshalJSON(data []byte) error {
return fmt.Errorf("argument json err: %v", err)
}
a.Type, err = NewType(extarg.Type)
argument.Type, err = NewType(extarg.Type)
if err != nil {
return err
}
a.Name = extarg.Name
a.Indexed = extarg.Indexed
argument.Name = extarg.Name
argument.Indexed = extarg.Indexed
return nil
}
// LengthNonIndexed returns the number of arguments when not counting 'indexed' ones. Only events
// can ever have 'indexed' arguments, it should always be false on arguments for method input/output
func (arguments Arguments) LengthNonIndexed() int {
out := 0
for _, arg := range arguments {
if !arg.Indexed {
out++
}
}
return out
}
// isTuple returns true for non-atomic constructs, like (uint,uint) or uint[]
func (arguments Arguments) isTuple() bool {
return len(arguments) > 1
}
// Unpack performs the operation hexdata -> Go format
func (arguments Arguments) Unpack(v interface{}, data []byte) error {
if arguments.isTuple() {
return arguments.unpackTuple(v, data)
}
return arguments.unpackAtomic(v, data)
}
func (arguments Arguments) unpackTuple(v interface{}, output []byte) error {
// make sure the passed value is arguments pointer
valueOf := reflect.ValueOf(v)
if reflect.Ptr != valueOf.Kind() {
return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
}
var (
value = valueOf.Elem()
typ = value.Type()
kind = value.Kind()
)
if err := requireUnpackKind(value, typ, kind, arguments); err != nil {
return err
}
// `i` counts the nonindexed arguments.
// `j` counts the number of complex types.
// both `i` and `j` are used to to correctly compute `data` offset.
i, j := -1, 0
for _, arg := range arguments {
if arg.Indexed {
// can't read, continue
continue
}
i++
marshalledValue, err := toGoType((i+j)*32, arg.Type, output)
if err != nil {
return err
}
if arg.Type.T == ArrayTy {
// combined index ('i' + 'j') need to be adjusted only by size of array, thus
// we need to decrement 'j' because 'i' was incremented
j += arg.Type.Size - 1
}
reflectValue := reflect.ValueOf(marshalledValue)
switch kind {
case reflect.Struct:
for j := 0; j < typ.NumField(); j++ {
field := typ.Field(j)
// TODO read tags: `abi:"fieldName"`
if field.Name == strings.ToUpper(arg.Name[:1])+arg.Name[1:] {
if err := set(value.Field(j), reflectValue, arg); err != nil {
return err
}
}
}
case reflect.Slice, reflect.Array:
if value.Len() < i {
return fmt.Errorf("abi: insufficient number of arguments for unpack, want %d, got %d", len(arguments), value.Len())
}
v := value.Index(i)
if err := requireAssignable(v, reflectValue); err != nil {
return err
}
if err := set(v.Elem(), reflectValue, arg); err != nil {
return err
}
default:
return fmt.Errorf("abi:[2] cannot unmarshal tuple in to %v", typ)
}
}
return nil
}
// unpackAtomic unpacks ( hexdata -> go ) a single value
func (arguments Arguments) unpackAtomic(v interface{}, output []byte) error {
// make sure the passed value is arguments pointer
valueOf := reflect.ValueOf(v)
if reflect.Ptr != valueOf.Kind() {
return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
}
arg := arguments[0]
if arg.Indexed {
return fmt.Errorf("abi: attempting to unpack indexed variable into element.")
}
value := valueOf.Elem()
marshalledValue, err := toGoType(0, arg.Type, output)
if err != nil {
return err
}
return set(value, reflect.ValueOf(marshalledValue), arg)
}
// Unpack performs the operation Go format -> Hexdata
func (arguments Arguments) Pack(args ...interface{}) ([]byte, error) {
// Make sure arguments match up and pack them
abiArgs := arguments
if len(args) != len(abiArgs) {
return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(abiArgs))
}
// variable input is the output appended at the end of packed
// output. This is used for strings and bytes types input.
var variableInput []byte
// input offset is the bytes offset for packed output
inputOffset := 0
for _, abiArg := range abiArgs {
if abiArg.Type.T == ArrayTy {
inputOffset += (32 * abiArg.Type.Size)
} else {
inputOffset += 32
}
}
var ret []byte
for i, a := range args {
input := abiArgs[i]
// pack the input
packed, err := input.Type.pack(reflect.ValueOf(a))
if err != nil {
return nil, err
}
// check for a slice type (string, bytes, slice)
if input.Type.requiresLengthPrefix() {
// calculate the offset
offset := inputOffset + len(variableInput)
// set the offset
ret = append(ret, packNum(reflect.ValueOf(offset))...)
// Append the packed output to the variable input. The variable input
// will be appended at the end of the input.
variableInput = append(variableInput, packed...)
} else {
// append the packed value to the input
ret = append(ret, packed...)
}
}
// append the variable input at the end of the packed input
ret = append(ret, variableInput...)
return ret, nil
}

@ -18,7 +18,6 @@ package abi
import (
"fmt"
"reflect"
"strings"
"github.com/ethereum/go-ethereum/common"
@ -31,7 +30,7 @@ import (
type Event struct {
Name string
Anonymous bool
Inputs []Argument
Inputs Arguments
}
// Id returns the canonical representation of the event's signature used by the
@ -45,95 +44,3 @@ func (e Event) Id() common.Hash {
}
return common.BytesToHash(crypto.Keccak256([]byte(fmt.Sprintf("%v(%v)", e.Name, strings.Join(types, ",")))))
}
// unpacks an event return tuple into a struct of corresponding go types
//
// Unpacking can be done into a struct or a slice/array.
func (e Event) tupleUnpack(v interface{}, output []byte) error {
// make sure the passed value is a pointer
valueOf := reflect.ValueOf(v)
if reflect.Ptr != valueOf.Kind() {
return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
}
var (
value = valueOf.Elem()
typ = value.Type()
)
if value.Kind() != reflect.Struct {
return fmt.Errorf("abi: cannot unmarshal tuple in to %v", typ)
}
j := 0
for i := 0; i < len(e.Inputs); i++ {
input := e.Inputs[i]
if input.Indexed {
// can't read, continue
continue
}
marshalledValue, err := toGoType((i+j)*32, input.Type, output)
if err != nil {
return err
}
if input.Type.T == ArrayTy {
// combined index ('i' + 'j') need to be adjusted only by size of array, thus
// we need to decrement 'j' because 'i' was incremented
j += input.Type.Size - 1
}
reflectValue := reflect.ValueOf(marshalledValue)
switch value.Kind() {
case reflect.Struct:
for j := 0; j < typ.NumField(); j++ {
field := typ.Field(j)
// TODO read tags: `abi:"fieldName"`
if field.Name == strings.ToUpper(e.Inputs[i].Name[:1])+e.Inputs[i].Name[1:] {
if err := set(value.Field(j), reflectValue, e.Inputs[i]); err != nil {
return err
}
}
}
case reflect.Slice, reflect.Array:
if value.Len() < i {
return fmt.Errorf("abi: insufficient number of arguments for unpack, want %d, got %d", len(e.Inputs), value.Len())
}
v := value.Index(i)
if v.Kind() != reflect.Ptr && v.Kind() != reflect.Interface {
return fmt.Errorf("abi: cannot unmarshal %v in to %v", v.Type(), reflectValue.Type())
}
reflectValue := reflect.ValueOf(marshalledValue)
if err := set(v.Elem(), reflectValue, e.Inputs[i]); err != nil {
return err
}
default:
return fmt.Errorf("abi: cannot unmarshal tuple in to %v", typ)
}
}
return nil
}
func (e Event) isTupleReturn() bool { return len(e.Inputs) > 1 }
func (e Event) singleUnpack(v interface{}, output []byte) error {
// make sure the passed value is a pointer
valueOf := reflect.ValueOf(v)
if reflect.Ptr != valueOf.Kind() {
return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
}
if e.Inputs[0].Indexed {
return fmt.Errorf("abi: attempting to unpack indexed variable into element.")
}
value := valueOf.Elem()
marshalledValue, err := toGoType(0, e.Inputs[0].Type, output)
if err != nil {
return err
}
if err := set(value, reflect.ValueOf(marshalledValue), e.Inputs[0]); err != nil {
return err
}
return nil
}

@ -18,15 +18,52 @@ package abi
import (
"bytes"
"encoding/hex"
"encoding/json"
"math/big"
"reflect"
"strings"
"testing"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/crypto"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
var jsonEventTransfer = []byte(`{
"anonymous": false,
"inputs": [
{
"indexed": true, "name": "from", "type": "address"
}, {
"indexed": true, "name": "to", "type": "address"
}, {
"indexed": false, "name": "value", "type": "uint256"
}],
"name": "Transfer",
"type": "event"
}`)
var jsonEventPledge = []byte(`{
"anonymous": false,
"inputs": [{
"indexed": false, "name": "who", "type": "address"
}, {
"indexed": false, "name": "wad", "type": "uint128"
}, {
"indexed": false, "name": "currency", "type": "bytes3"
}],
"name": "Pledge",
"type": "event"
}`)
// 1000000
var transferData1 = "00000000000000000000000000000000000000000000000000000000000f4240"
// "0x00Ce0d46d924CC8437c806721496599FC3FFA268", 2218516807680, "usd"
var pledgeData1 = "00000000000000000000000000ce0d46d924cc8437c806721496599fc3ffa2680000000000000000000000000000000000000000000000000000020489e800007573640000000000000000000000000000000000000000000000000000000000"
func TestEventId(t *testing.T) {
var table = []struct {
definition string
@ -77,3 +114,203 @@ func TestEventMultiValueWithArrayUnpack(t *testing.T) {
require.Equal(t, [2]uint8{1, 2}, rst.Value1)
require.Equal(t, uint8(3), rst.Value2)
}
func TestEventTupleUnpack(t *testing.T) {
type EventTransfer struct {
Value *big.Int
}
type EventPledge struct {
Who common.Address
Wad *big.Int
Currency [3]byte
}
type BadEventPledge struct {
Who string
Wad int
Currency [3]byte
}
bigint := new(big.Int)
bigintExpected := big.NewInt(1000000)
bigintExpected2 := big.NewInt(2218516807680)
addr := common.HexToAddress("0x00Ce0d46d924CC8437c806721496599FC3FFA268")
var testCases = []struct {
data string
dest interface{}
expected interface{}
jsonLog []byte
error string
name string
}{{
transferData1,
&EventTransfer{},
&EventTransfer{Value: bigintExpected},
jsonEventTransfer,
"",
"Can unpack ERC20 Transfer event into structure",
}, {
transferData1,
&[]interface{}{&bigint},
&[]interface{}{&bigintExpected},
jsonEventTransfer,
"",
"Can unpack ERC20 Transfer event into slice",
}, {
pledgeData1,
&EventPledge{},
&EventPledge{
addr,
bigintExpected2,
[3]byte{'u', 's', 'd'}},
jsonEventPledge,
"",
"Can unpack Pledge event into structure",
}, {
pledgeData1,
&[]interface{}{&common.Address{}, &bigint, &[3]byte{}},
&[]interface{}{
&addr,
&bigintExpected2,
&[3]byte{'u', 's', 'd'}},
jsonEventPledge,
"",
"Can unpack Pledge event into slice",
}, {
pledgeData1,
&[3]interface{}{&common.Address{}, &bigint, &[3]byte{}},
&[3]interface{}{
&addr,
&bigintExpected2,
&[3]byte{'u', 's', 'd'}},
jsonEventPledge,
"",
"Can unpack Pledge event into an array",
}, {
pledgeData1,
&[]interface{}{new(int), 0, 0},
&[]interface{}{},
jsonEventPledge,
"abi: cannot unmarshal common.Address in to int",
"Can not unpack Pledge event into slice with wrong types",
}, {
pledgeData1,
&BadEventPledge{},
&BadEventPledge{},
jsonEventPledge,
"abi: cannot unmarshal common.Address in to string",
"Can not unpack Pledge event into struct with wrong filed types",
}, {
pledgeData1,
&[]interface{}{common.Address{}, new(big.Int)},
&[]interface{}{},
jsonEventPledge,
"abi: insufficient number of elements in the list/array for unpack, want 3, got 2",
"Can not unpack Pledge event into too short slice",
}, {
pledgeData1,
new(map[string]interface{}),
&[]interface{}{},
jsonEventPledge,
"abi: cannot unmarshal tuple into map[string]interface {}",
"Can not unpack Pledge event into map",
}}
for _, tc := range testCases {
assert := assert.New(t)
tc := tc
t.Run(tc.name, func(t *testing.T) {
err := unpackTestEventData(tc.dest, tc.data, tc.jsonLog, assert)
if tc.error == "" {
assert.Nil(err, "Should be able to unpack event data.")
assert.Equal(tc.expected, tc.dest, tc.name)
} else {
assert.EqualError(err, tc.error)
}
})
}
}
func unpackTestEventData(dest interface{}, hexData string, jsonEvent []byte, assert *assert.Assertions) error {
data, err := hex.DecodeString(hexData)
assert.NoError(err, "Hex data should be a correct hex-string")
var e Event
assert.NoError(json.Unmarshal(jsonEvent, &e), "Should be able to unmarshal event ABI")
a := ABI{Events: map[string]Event{"e": e}}
return a.Unpack(dest, "e", data)
}
/*
Taken from
https://github.com/ethereum/go-ethereum/pull/15568
*/
type testResult struct {
Values [2]*big.Int
Value1 *big.Int
Value2 *big.Int
}
type testCase struct {
definition string
want testResult
}
func (tc testCase) encoded(intType, arrayType Type) []byte {
var b bytes.Buffer
if tc.want.Value1 != nil {
val, _ := intType.pack(reflect.ValueOf(tc.want.Value1))
b.Write(val)
}
if !reflect.DeepEqual(tc.want.Values, [2]*big.Int{nil, nil}) {
val, _ := arrayType.pack(reflect.ValueOf(tc.want.Values))
b.Write(val)
}
if tc.want.Value2 != nil {
val, _ := intType.pack(reflect.ValueOf(tc.want.Value2))
b.Write(val)
}
return b.Bytes()
}
// TestEventUnpackIndexed verifies that indexed field will be skipped by event decoder.
func TestEventUnpackIndexed(t *testing.T) {
definition := `[{"name": "test", "type": "event", "inputs": [{"indexed": true, "name":"value1", "type":"uint8"},{"indexed": false, "name":"value2", "type":"uint8"}]}]`
type testStruct struct {
Value1 uint8
Value2 uint8
}
abi, err := JSON(strings.NewReader(definition))
require.NoError(t, err)
var b bytes.Buffer
b.Write(packNum(reflect.ValueOf(uint8(8))))
var rst testStruct
require.NoError(t, abi.Unpack(&rst, "test", b.Bytes()))
require.Equal(t, uint8(0), rst.Value1)
require.Equal(t, uint8(8), rst.Value2)
}
// TestEventIndexedWithArrayUnpack verifies that decoder will not overlow when static array is indexed input.
func TestEventIndexedWithArrayUnpack(t *testing.T) {
definition := `[{"name": "test", "type": "event", "inputs": [{"indexed": true, "name":"value1", "type":"uint8[2]"},{"indexed": false, "name":"value2", "type":"string"}]}]`
type testStruct struct {
Value1 [2]uint8
Value2 string
}
abi, err := JSON(strings.NewReader(definition))
require.NoError(t, err)
var b bytes.Buffer
stringOut := "abc"
// number of fields that will be encoded * 32
b.Write(packNum(reflect.ValueOf(32)))
b.Write(packNum(reflect.ValueOf(len(stringOut))))
b.Write(common.RightPadBytes([]byte(stringOut), 32))
var rst testStruct
require.NoError(t, abi.Unpack(&rst, "test", b.Bytes()))
require.Equal(t, [2]uint8{0, 0}, rst.Value1)
require.Equal(t, stringOut, rst.Value2)
}

@ -18,13 +18,12 @@ package abi
import (
"fmt"
"reflect"
"strings"
"github.com/ethereum/go-ethereum/crypto"
)
// Callable method given a `Name` and whether the method is a constant.
// Method represents a callable given a `Name` and whether the method is a constant.
// If the method is `Const` no transaction needs to be created for this
// particular Method call. It can easily be simulated using a local VM.
// For example a `Balance()` method only needs to retrieve something
@ -35,137 +34,8 @@ import (
type Method struct {
Name string
Const bool
Inputs []Argument
Outputs []Argument
}
func (method Method) pack(args ...interface{}) ([]byte, error) {
// Make sure arguments match up and pack them
if len(args) != len(method.Inputs) {
return nil, fmt.Errorf("argument count mismatch: %d for %d", len(args), len(method.Inputs))
}
// variable input is the output appended at the end of packed
// output. This is used for strings and bytes types input.
var variableInput []byte
// input offset is the bytes offset for packed output
inputOffset := 0
for _, input := range method.Inputs {
if input.Type.T == ArrayTy {
inputOffset += (32 * input.Type.Size)
} else {
inputOffset += 32
}
}
var ret []byte
for i, a := range args {
input := method.Inputs[i]
// pack the input
packed, err := input.Type.pack(reflect.ValueOf(a))
if err != nil {
return nil, fmt.Errorf("`%s` %v", method.Name, err)
}
// check for a slice type (string, bytes, slice)
if input.Type.requiresLengthPrefix() {
// calculate the offset
offset := inputOffset + len(variableInput)
// set the offset
ret = append(ret, packNum(reflect.ValueOf(offset))...)
// Append the packed output to the variable input. The variable input
// will be appended at the end of the input.
variableInput = append(variableInput, packed...)
} else {
// append the packed value to the input
ret = append(ret, packed...)
}
}
// append the variable input at the end of the packed input
ret = append(ret, variableInput...)
return ret, nil
}
// unpacks a method return tuple into a struct of corresponding go types
//
// Unpacking can be done into a struct or a slice/array.
func (method Method) tupleUnpack(v interface{}, output []byte) error {
// make sure the passed value is a pointer
valueOf := reflect.ValueOf(v)
if reflect.Ptr != valueOf.Kind() {
return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
}
var (
value = valueOf.Elem()
typ = value.Type()
)
j := 0
for i := 0; i < len(method.Outputs); i++ {
toUnpack := method.Outputs[i]
marshalledValue, err := toGoType((i+j)*32, toUnpack.Type, output)
if err != nil {
return err
}
if toUnpack.Type.T == ArrayTy {
// combined index ('i' + 'j') need to be adjusted only by size of array, thus
// we need to decrement 'j' because 'i' was incremented
j += toUnpack.Type.Size - 1
}
reflectValue := reflect.ValueOf(marshalledValue)
switch value.Kind() {
case reflect.Struct:
for j := 0; j < typ.NumField(); j++ {
field := typ.Field(j)
// TODO read tags: `abi:"fieldName"`
if field.Name == strings.ToUpper(method.Outputs[i].Name[:1])+method.Outputs[i].Name[1:] {
if err := set(value.Field(j), reflectValue, method.Outputs[i]); err != nil {
return err
}
}
}
case reflect.Slice, reflect.Array:
if value.Len() < i {
return fmt.Errorf("abi: insufficient number of arguments for unpack, want %d, got %d", len(method.Outputs), value.Len())
}
v := value.Index(i)
if v.Kind() != reflect.Ptr && v.Kind() != reflect.Interface {
return fmt.Errorf("abi: cannot unmarshal %v in to %v", v.Type(), reflectValue.Type())
}
reflectValue := reflect.ValueOf(marshalledValue)
if err := set(v.Elem(), reflectValue, method.Outputs[i]); err != nil {
return err
}
default:
return fmt.Errorf("abi: cannot unmarshal tuple in to %v", typ)
}
}
return nil
}
func (method Method) isTupleReturn() bool { return len(method.Outputs) > 1 }
func (method Method) singleUnpack(v interface{}, output []byte) error {
// make sure the passed value is a pointer
valueOf := reflect.ValueOf(v)
if reflect.Ptr != valueOf.Kind() {
return fmt.Errorf("abi: Unpack(non-pointer %T)", v)
}
value := valueOf.Elem()
marshalledValue, err := toGoType(0, method.Outputs[0].Type, output)
if err != nil {
return err
}
if err := set(value, reflect.ValueOf(marshalledValue), method.Outputs[0]); err != nil {
return err
}
return nil
Inputs Arguments
Outputs Arguments
}
// Sig returns the methods string signature according to the ABI spec.
@ -175,35 +45,35 @@ func (method Method) singleUnpack(v interface{}, output []byte) error {
// function foo(uint32 a, int b) = "foo(uint32,int256)"
//
// Please note that "int" is substitute for its canonical representation "int256"
func (m Method) Sig() string {
types := make([]string, len(m.Inputs))
func (method Method) Sig() string {
types := make([]string, len(method.Inputs))
i := 0
for _, input := range m.Inputs {
for _, input := range method.Inputs {
types[i] = input.Type.String()
i++
}
return fmt.Sprintf("%v(%v)", m.Name, strings.Join(types, ","))
return fmt.Sprintf("%v(%v)", method.Name, strings.Join(types, ","))
}
func (m Method) String() string {
inputs := make([]string, len(m.Inputs))
for i, input := range m.Inputs {
func (method Method) String() string {
inputs := make([]string, len(method.Inputs))
for i, input := range method.Inputs {
inputs[i] = fmt.Sprintf("%v %v", input.Name, input.Type)
}
outputs := make([]string, len(m.Outputs))
for i, output := range m.Outputs {
outputs := make([]string, len(method.Outputs))
for i, output := range method.Outputs {
if len(output.Name) > 0 {
outputs[i] = fmt.Sprintf("%v ", output.Name)
}
outputs[i] += output.Type.String()
}
constant := ""
if m.Const {
if method.Const {
constant = "constant "
}
return fmt.Sprintf("function %v(%v) %sreturns(%v)", m.Name, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", "))
return fmt.Sprintf("function %v(%v) %sreturns(%v)", method.Name, strings.Join(inputs, ", "), constant, strings.Join(outputs, ", "))
}
func (m Method) Id() []byte {
return crypto.Keccak256([]byte(m.Sig()))[:4]
func (method Method) Id() []byte {
return crypto.Keccak256([]byte(method.Sig()))[:4]
}

@ -48,9 +48,8 @@ func packElement(t Type, reflectValue reflect.Value) []byte {
case BoolTy:
if reflectValue.Bool() {
return math.PaddedBigBytes(common.Big1, 32)
} else {
return math.PaddedBigBytes(common.Big0, 32)
}
return math.PaddedBigBytes(common.Big0, 32)
case BytesTy:
if reflectValue.Kind() == reflect.Array {
reflectValue = mustArrayToByteSlice(reflectValue)

@ -85,3 +85,28 @@ func set(dst, src reflect.Value, output Argument) error {
}
return nil
}
// requireAssignable assures that `dest` is a pointer and it's not an interface.
func requireAssignable(dst, src reflect.Value) error {
if dst.Kind() != reflect.Ptr && dst.Kind() != reflect.Interface {
return fmt.Errorf("abi: cannot unmarshal %v into %v", src.Type(), dst.Type())
}
return nil
}
// requireUnpackKind verifies preconditions for unpacking `args` into `kind`
func requireUnpackKind(v reflect.Value, t reflect.Type, k reflect.Kind,
args Arguments) error {
switch k {
case reflect.Struct:
case reflect.Slice, reflect.Array:
if minLen := args.LengthNonIndexed(); v.Len() < minLen {
return fmt.Errorf("abi: insufficient number of elements in the list/array for unpack, want %d, got %d",
minLen, v.Len())
}
default:
return fmt.Errorf("abi: cannot unmarshal tuple into %v", t)
}
return nil
}

@ -24,6 +24,7 @@ import (
"strings"
)
// Type enumerator
const (
IntTy byte = iota
UintTy
@ -100,69 +101,66 @@ func NewType(t string) (typ Type, err error) {
return Type{}, fmt.Errorf("invalid formatting of array type")
}
return typ, err
} else {
// parse the type and size of the abi-type.
parsedType := typeRegex.FindAllStringSubmatch(t, -1)[0]
// varSize is the size of the variable
var varSize int
if len(parsedType[3]) > 0 {
var err error
varSize, err = strconv.Atoi(parsedType[2])
if err != nil {
return Type{}, fmt.Errorf("abi: error parsing variable size: %v", err)
}
} else {
if parsedType[0] == "uint" || parsedType[0] == "int" {
// this should fail because it means that there's something wrong with
// the abi type (the compiler should always format it to the size...always)
return Type{}, fmt.Errorf("unsupported arg type: %s", t)
}
}
// parse the type and size of the abi-type.
parsedType := typeRegex.FindAllStringSubmatch(t, -1)[0]
// varSize is the size of the variable
var varSize int
if len(parsedType[3]) > 0 {
var err error
varSize, err = strconv.Atoi(parsedType[2])
if err != nil {
return Type{}, fmt.Errorf("abi: error parsing variable size: %v", err)
}
// varType is the parsed abi type
varType := parsedType[1]
switch varType {
case "int":
typ.Kind, typ.Type = reflectIntKindAndType(false, varSize)
typ.Size = varSize
typ.T = IntTy
case "uint":
typ.Kind, typ.Type = reflectIntKindAndType(true, varSize)
typ.Size = varSize
typ.T = UintTy
case "bool":
typ.Kind = reflect.Bool
typ.T = BoolTy
typ.Type = reflect.TypeOf(bool(false))
case "address":
typ.Kind = reflect.Array
typ.Type = address_t
typ.Size = 20
typ.T = AddressTy
case "string":
typ.Kind = reflect.String
typ.Type = reflect.TypeOf("")
typ.T = StringTy
case "bytes":
if varSize == 0 {
typ.T = BytesTy
typ.Kind = reflect.Slice
typ.Type = reflect.SliceOf(reflect.TypeOf(byte(0)))
} else {
typ.T = FixedBytesTy
typ.Kind = reflect.Array
typ.Size = varSize
typ.Type = reflect.ArrayOf(varSize, reflect.TypeOf(byte(0)))
}
case "function":
typ.Kind = reflect.Array
typ.T = FunctionTy
typ.Size = 24
typ.Type = reflect.ArrayOf(24, reflect.TypeOf(byte(0)))
default:
} else {
if parsedType[0] == "uint" || parsedType[0] == "int" {
// this should fail because it means that there's something wrong with
// the abi type (the compiler should always format it to the size...always)
return Type{}, fmt.Errorf("unsupported arg type: %s", t)
}
}
// varType is the parsed abi type
switch varType := parsedType[1]; varType {
case "int":
typ.Kind, typ.Type = reflectIntKindAndType(false, varSize)
typ.Size = varSize
typ.T = IntTy
case "uint":
typ.Kind, typ.Type = reflectIntKindAndType(true, varSize)
typ.Size = varSize
typ.T = UintTy
case "bool":
typ.Kind = reflect.Bool
typ.T = BoolTy
typ.Type = reflect.TypeOf(bool(false))
case "address":
typ.Kind = reflect.Array
typ.Type = address_t
typ.Size = 20
typ.T = AddressTy
case "string":
typ.Kind = reflect.String
typ.Type = reflect.TypeOf("")
typ.T = StringTy
case "bytes":
if varSize == 0 {
typ.T = BytesTy
typ.Kind = reflect.Slice
typ.Type = reflect.SliceOf(reflect.TypeOf(byte(0)))
} else {
typ.T = FixedBytesTy
typ.Kind = reflect.Array
typ.Size = varSize
typ.Type = reflect.ArrayOf(varSize, reflect.TypeOf(byte(0)))
}
case "function":
typ.Kind = reflect.Array
typ.T = FunctionTy
typ.Size = 24
typ.Type = reflect.ArrayOf(24, reflect.TypeOf(byte(0)))
default:
return Type{}, fmt.Errorf("unsupported arg type: %s", t)
}
return
}

@ -25,15 +25,6 @@ import (
"github.com/ethereum/go-ethereum/common"
)
// unpacker is a utility interface that enables us to have
// abstraction between events and methods and also to properly
// "unpack" them; e.g. events use Inputs, methods use Outputs.
type unpacker interface {
tupleUnpack(v interface{}, output []byte) error
singleUnpack(v interface{}, output []byte) error
isTupleReturn() bool
}
// reads the integer based on its kind
func readInteger(kind reflect.Kind, b []byte) interface{} {
switch kind {
@ -79,7 +70,7 @@ func readBool(word []byte) (bool, error) {
// This enforces that standard by always presenting it as a 24-array (address + sig = 24 bytes)
func readFunctionType(t Type, word []byte) (funcTy [24]byte, err error) {
if t.T != FunctionTy {
return [24]byte{}, fmt.Errorf("abi: invalid type in call to make function type byte array.")
return [24]byte{}, fmt.Errorf("abi: invalid type in call to make function type byte array")
}
if garbage := binary.BigEndian.Uint64(word[24:32]); garbage != 0 {
err = fmt.Errorf("abi: got improperly encoded function type, got %v", word)
@ -92,7 +83,7 @@ func readFunctionType(t Type, word []byte) (funcTy [24]byte, err error) {
// through reflection, creates a fixed array to be read from
func readFixedBytes(t Type, word []byte) (interface{}, error) {
if t.T != FixedBytesTy {
return nil, fmt.Errorf("abi: invalid type in call to make fixed byte array.")
return nil, fmt.Errorf("abi: invalid type in call to make fixed byte array")
}
// convert
array := reflect.New(t.Type).Elem()

@ -27,6 +27,7 @@ import (
"testing"
"github.com/ethereum/go-ethereum/common"
"github.com/stretchr/testify/require"
)
type unpackTest struct {
@ -286,56 +287,83 @@ func TestUnpack(t *testing.T) {
}
}
func TestMultiReturnWithStruct(t *testing.T) {
type methodMultiOutput struct {
Int *big.Int
String string
}
func methodMultiReturn(require *require.Assertions) (ABI, []byte, methodMultiOutput) {
const definition = `[
{ "name" : "multi", "constant" : false, "outputs": [ { "name": "Int", "type": "uint256" }, { "name": "String", "type": "string" } ] }]`
var expected = methodMultiOutput{big.NewInt(1), "hello"}
abi, err := JSON(strings.NewReader(definition))
if err != nil {
t.Fatal(err)
}
require.NoError(err)
// using buff to make the code readable
buff := new(bytes.Buffer)
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000001"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000040"))
buff.Write(common.Hex2Bytes("0000000000000000000000000000000000000000000000000000000000000005"))
stringOut := "hello"
buff.Write(common.RightPadBytes([]byte(stringOut), 32))
buff.Write(common.RightPadBytes([]byte(expected.String), 32))
return abi, buff.Bytes(), expected
}
var inter struct {
Int *big.Int
String string
}
err = abi.Unpack(&inter, "multi", buff.Bytes())
if err != nil {
t.Error(err)
}
if inter.Int == nil || inter.Int.Cmp(big.NewInt(1)) != 0 {
t.Error("expected Int to be 1 got", inter.Int)
}
if inter.String != stringOut {
t.Error("expected String to be", stringOut, "got", inter.String)
}
var reversed struct {
func TestMethodMultiReturn(t *testing.T) {
type reversed struct {
String string
Int *big.Int
}
err = abi.Unpack(&reversed, "multi", buff.Bytes())
if err != nil {
t.Error(err)
}
if reversed.Int == nil || reversed.Int.Cmp(big.NewInt(1)) != 0 {
t.Error("expected Int to be 1 got", reversed.Int)
}
if reversed.String != stringOut {
t.Error("expected String to be", stringOut, "got", reversed.String)
abi, data, expected := methodMultiReturn(require.New(t))
bigint := new(big.Int)
var testCases = []struct {
dest interface{}
expected interface{}
error string
name string
}{{
&methodMultiOutput{},
&expected,
"",
"Can unpack into structure",
}, {
&reversed{},
&reversed{expected.String, expected.Int},
"",
"Can unpack into reversed structure",
}, {
&[]interface{}{&bigint, new(string)},
&[]interface{}{&expected.Int, &expected.String},
"",
"Can unpack into a slice",
}, {
&[2]interface{}{&bigint, new(string)},
&[2]interface{}{&expected.Int, &expected.String},
"",
"Can unpack into an array",
}, {
&[]interface{}{new(int), new(int)},
&[]interface{}{&expected.Int, &expected.String},
"abi: cannot unmarshal *big.Int in to int",
"Can not unpack into a slice with wrong types",
}, {
&[]interface{}{new(int)},
&[]interface{}{},
"abi: insufficient number of elements in the list/array for unpack, want 2, got 1",
"Can not unpack into a slice with wrong types",
}}
for _, tc := range testCases {
tc := tc
t.Run(tc.name, func(t *testing.T) {
require := require.New(t)
err := abi.Unpack(tc.dest, "multi", data)
if tc.error == "" {
require.Nil(err, "Should be able to unpack method outputs.")
require.Equal(tc.expected, tc.dest)
} else {
require.EqualError(err, tc.error)
}
})
}
}