neoneo-go/pkg/core/state/contract.go

116 lines
3.1 KiB
Go

package state
import (
"encoding/json"
"errors"
"math"
"math/big"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/emit"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// Contract holds information about a smart contract in the NEO blockchain.
type Contract struct {
ID int32 `json:"id"`
UpdateCounter uint16 `json:"updatecounter"`
Hash util.Uint160 `json:"hash"`
Script []byte `json:"script"`
Manifest manifest.Manifest `json:"manifest"`
}
// DecodeBinary implements Serializable interface.
func (c *Contract) DecodeBinary(r *io.BinReader) {
si := stackitem.DecodeBinaryStackItem(r)
if r.Err != nil {
return
}
r.Err = c.FromStackItem(si)
}
// EncodeBinary implements Serializable interface.
func (c *Contract) EncodeBinary(w *io.BinWriter) {
si, err := c.ToStackItem()
if err != nil {
w.Err = err
return
}
stackitem.EncodeBinaryStackItem(si, w)
}
// ToStackItem converts state.Contract to stackitem.Item
func (c *Contract) ToStackItem() (stackitem.Item, error) {
manifest, err := json.Marshal(c.Manifest)
if err != nil {
return nil, err
}
return stackitem.NewArray([]stackitem.Item{
stackitem.Make(c.ID),
stackitem.Make(c.UpdateCounter),
stackitem.NewByteArray(c.Hash.BytesBE()),
stackitem.NewByteArray(c.Script),
stackitem.NewByteArray(manifest),
}), nil
}
// FromStackItem fills Contract's data from given stack itemized contract
// representation.
func (c *Contract) FromStackItem(item stackitem.Item) error {
arr, ok := item.Value().([]stackitem.Item)
if !ok {
return errors.New("not an array")
}
bi, ok := arr[0].Value().(*big.Int)
if !ok {
return errors.New("ID is not an integer")
}
if !bi.IsInt64() || bi.Int64() > math.MaxInt32 || bi.Int64() < math.MinInt32 {
return errors.New("ID not in int32 range")
}
c.ID = int32(bi.Int64())
bi, ok = arr[1].Value().(*big.Int)
if !ok {
return errors.New("UpdateCounter is not an integer")
}
if !bi.IsInt64() || bi.Int64() > math.MaxUint16 || bi.Int64() < 0 {
return errors.New("UpdateCounter not in uint16 range")
}
c.UpdateCounter = uint16(bi.Int64())
bytes, err := arr[2].TryBytes()
if err != nil {
return err
}
c.Hash, err = util.Uint160DecodeBytesBE(bytes)
if err != nil {
return err
}
bytes, err = arr[3].TryBytes()
if err != nil {
return err
}
c.Script = make([]byte, len(bytes))
copy(c.Script, bytes)
bytes, err = arr[4].TryBytes()
if err != nil {
return err
}
return json.Unmarshal(bytes, &c.Manifest)
}
// CreateContractHash creates deployed contract hash from transaction sender
// and contract script.
func CreateContractHash(sender util.Uint160, script []byte) util.Uint160 {
w := io.NewBufBinWriter()
emit.Opcodes(w.BinWriter, opcode.ABORT)
emit.Bytes(w.BinWriter, sender.BytesBE())
emit.Bytes(w.BinWriter, script)
if w.Err != nil {
panic(w.Err)
}
return hash.Hash160(w.Bytes())
}