neoneo-go/pkg/core/native/native_neo.go
Evgenii Stratonikov e0e7fd5367 native: cache GASPerBlock values
Close #1421.
2020-09-28 10:53:48 +03:00

737 lines
22 KiB
Go

package native
import (
"crypto/elliptic"
"errors"
"math/big"
"sort"
"strings"
"sync/atomic"
"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
"github.com/nspcc-dev/neo-go/pkg/core/dao"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"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/stackitem"
)
// NEO represents NEO native contract.
type NEO struct {
nep5TokenNative
GAS *GAS
// gasPerBlock represents current value of generated gas per block.
// It is append-only and doesn't need to be copied when used.
gasPerBlock atomic.Value
gasPerBlockChanged atomic.Value
votesChanged atomic.Value
nextValidators atomic.Value
validators atomic.Value
// committee contains cached committee members and
// is updated once in a while depending on committee size
// (every 28 blocks for mainnet). It's value
// is always equal to value stored by `prefixCommittee`.
committee atomic.Value
// committeeHash contains script hash of the committee.
committeeHash atomic.Value
}
// keyWithVotes is a serialized key with votes balance. It's not deserialized
// because some uses of it imply serialized-only usage and converting to
// PublicKey is quite expensive.
type keyWithVotes struct {
Key string
Votes *big.Int
}
const (
neoName = "NEO"
neoContractID = -1
// NEOTotalSupply is the total amount of NEO in the system.
NEOTotalSupply = 100000000
// prefixCandidate is a prefix used to store validator's data.
prefixCandidate = 33
// prefixVotersCount is a prefix for storing total amount of NEO of voters.
prefixVotersCount = 1
// prefixGasPerBlock is a prefix for storing amount of GAS generated per block.
prefixGASPerBlock = 29
// effectiveVoterTurnout represents minimal ratio of total supply to total amount voted value
// which is require to use non-standby validators.
effectiveVoterTurnout = 5
// neoHolderRewardRatio is a percent of generated GAS that is distributed to NEO holders.
neoHolderRewardRatio = 10
// neoHolderRewardRatio is a percent of generated GAS that is distributed to committee.
committeeRewardRatio = 5
// neoHolderRewardRatio is a percent of generated GAS that is distributed to voters.
voterRewardRatio = 85
)
var (
// prefixCommittee is a key used to store committee.
prefixCommittee = []byte{14}
)
// makeValidatorKey creates a key from account script hash.
func makeValidatorKey(key *keys.PublicKey) []byte {
b := key.Bytes()
// Don't create a new buffer.
b = append(b, 0)
copy(b[1:], b[0:])
b[0] = prefixCandidate
return b
}
// NewNEO returns NEO native contract.
func NewNEO() *NEO {
n := &NEO{}
nep5 := newNEP5Native(neoName)
nep5.symbol = "neo"
nep5.decimals = 0
nep5.factor = 1
nep5.onPersist = chainOnPersist(nep5.OnPersist, n.OnPersist)
nep5.postPersist = chainOnPersist(nep5.postPersist, n.PostPersist)
nep5.incBalance = n.increaseBalance
nep5.ContractID = neoContractID
n.nep5TokenNative = *nep5
n.votesChanged.Store(true)
n.nextValidators.Store(keys.PublicKeys(nil))
n.validators.Store(keys.PublicKeys(nil))
n.committee.Store(keys.PublicKeys(nil))
n.committeeHash.Store(util.Uint160{})
onp := n.Methods["onPersist"]
onp.Func = getOnPersistWrapper(n.onPersist)
n.Methods["onPersist"] = onp
pp := n.Methods["postPersist"]
pp.Func = getOnPersistWrapper(n.postPersist)
n.Methods["postPersist"] = pp
desc := newDescriptor("unclaimedGas", smartcontract.IntegerType,
manifest.NewParameter("account", smartcontract.Hash160Type),
manifest.NewParameter("end", smartcontract.IntegerType))
md := newMethodAndPrice(n.unclaimedGas, 3000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("registerCandidate", smartcontract.BoolType,
manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
md = newMethodAndPrice(n.registerCandidate, 5000000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("unregisterCandidate", smartcontract.BoolType,
manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
md = newMethodAndPrice(n.unregisterCandidate, 5000000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("vote", smartcontract.BoolType,
manifest.NewParameter("account", smartcontract.Hash160Type),
manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
md = newMethodAndPrice(n.vote, 500000000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("getCandidates", smartcontract.ArrayType)
md = newMethodAndPrice(n.getCandidatesCall, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("getСommittee", smartcontract.ArrayType)
md = newMethodAndPrice(n.getCommittee, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("getNextBlockValidators", smartcontract.ArrayType)
md = newMethodAndPrice(n.getNextBlockValidators, 100000000, smartcontract.AllowStates)
n.AddMethod(md, desc, true)
desc = newDescriptor("getGasPerBlock", smartcontract.IntegerType)
md = newMethodAndPrice(n.getGASPerBlock, 100_0000, smartcontract.AllowStates)
n.AddMethod(md, desc, false)
desc = newDescriptor("setGasPerBlock", smartcontract.BoolType,
manifest.NewParameter("gasPerBlock", smartcontract.IntegerType))
md = newMethodAndPrice(n.setGASPerBlock, 500_0000, smartcontract.AllowModifyStates)
n.AddMethod(md, desc, false)
return n
}
// Initialize initializes NEO contract.
func (n *NEO) Initialize(ic *interop.Context) error {
if err := n.nep5TokenNative.Initialize(ic); err != nil {
return err
}
if n.nep5TokenNative.getTotalSupply(ic.DAO).Sign() != 0 {
return errors.New("already initialized")
}
committee := ic.Chain.GetStandByCommittee()
n.committee.Store(committee)
script, err := smartcontract.CreateMajorityMultiSigRedeemScript(committee.Copy())
if err != nil {
return err
}
n.committeeHash.Store(hash.Hash160(script))
n.updateNextValidators(committee, ic.Chain)
err = ic.DAO.PutStorageItem(n.ContractID, prefixCommittee, &state.StorageItem{Value: committee.Bytes()})
if err != nil {
return err
}
h, err := getStandbyValidatorsHash(ic)
if err != nil {
return err
}
n.mint(ic, h, big.NewInt(NEOTotalSupply))
gr := &state.GASRecord{{Index: 0, GASPerBlock: *big.NewInt(5 * GASFactor)}}
n.gasPerBlock.Store(*gr)
n.gasPerBlockChanged.Store(false)
err = ic.DAO.PutStorageItem(n.ContractID, []byte{prefixGASPerBlock}, &state.StorageItem{Value: gr.Bytes()})
if err != nil {
return err
}
err = ic.DAO.PutStorageItem(n.ContractID, []byte{prefixVotersCount}, &state.StorageItem{Value: []byte{}})
if err != nil {
return err
}
return nil
}
func (n *NEO) updateNextValidators(committee keys.PublicKeys, bc blockchainer.Blockchainer) {
nextVals := committee[:bc.GetConfig().ValidatorsCount].Copy()
sort.Sort(nextVals)
n.nextValidators.Store(nextVals)
}
func (n *NEO) updateCommittee(ic *interop.Context) error {
votesChanged := n.votesChanged.Load().(bool)
if !votesChanged {
// We need to put in storage anyway, as it affects dumps
committee := n.committee.Load().(keys.PublicKeys)
si := &state.StorageItem{Value: committee.Bytes()}
return ic.DAO.PutStorageItem(n.ContractID, prefixCommittee, si)
}
committee, err := n.ComputeCommitteeMembers(ic.Chain, ic.DAO)
if err != nil {
return err
}
n.committee.Store(committee)
script, err := smartcontract.CreateMajorityMultiSigRedeemScript(committee.Copy())
if err != nil {
return err
}
n.committeeHash.Store(hash.Hash160(script))
n.updateNextValidators(committee, ic.Chain)
n.votesChanged.Store(false)
si := &state.StorageItem{Value: committee.Bytes()}
return ic.DAO.PutStorageItem(n.ContractID, prefixCommittee, si)
}
func shouldUpdateCommittee(h uint32, bc blockchainer.Blockchainer) bool {
cfg := bc.GetConfig()
r := cfg.ValidatorsCount + len(cfg.StandbyCommittee)
return h%uint32(r) == 0
}
// OnPersist implements Contract interface.
func (n *NEO) OnPersist(ic *interop.Context) error {
if shouldUpdateCommittee(ic.Block.Index, ic.Chain) {
if err := n.updateCommittee(ic); err != nil {
return err
}
}
return nil
}
// PostPersist implements Contract interface.
func (n *NEO) PostPersist(ic *interop.Context) error {
gas := n.GetGASPerBlock(ic.DAO, ic.Block.Index)
pubs := n.GetCommitteeMembers()
index := int(ic.Block.Index) % len(ic.Chain.GetConfig().StandbyCommittee)
gas.Mul(gas, big.NewInt(committeeRewardRatio))
n.GAS.mint(ic, pubs[index].GetScriptHash(), gas.Div(gas, big.NewInt(100)))
n.OnPersistEnd(ic.DAO)
return nil
}
// OnPersistEnd updates cached values if they've been changed.
func (n *NEO) OnPersistEnd(d dao.DAO) {
if n.gasPerBlockChanged.Load().(bool) {
gr := n.getGASRecordFromDAO(d)
n.gasPerBlock.Store(gr)
n.gasPerBlockChanged.Store(false)
}
}
func (n *NEO) increaseBalance(ic *interop.Context, h util.Uint160, si *state.StorageItem, amount *big.Int) error {
acc, err := state.NEOBalanceStateFromBytes(si.Value)
if err != nil {
return err
}
if amount.Sign() == -1 && acc.Balance.Cmp(new(big.Int).Neg(amount)) == -1 {
return errors.New("insufficient funds")
}
if err := n.distributeGas(ic, h, acc); err != nil {
return err
}
if amount.Sign() == 0 {
si.Value = acc.Bytes()
return nil
}
if err := n.ModifyAccountVotes(acc, ic.DAO, amount, modifyVoteTransfer); err != nil {
return err
}
if acc.VoteTo != nil {
if err := n.modifyVoterTurnout(ic.DAO, amount); err != nil {
return err
}
}
acc.Balance.Add(&acc.Balance, amount)
if acc.Balance.Sign() != 0 {
si.Value = acc.Bytes()
} else {
si.Value = nil
}
return nil
}
func (n *NEO) distributeGas(ic *interop.Context, h util.Uint160, acc *state.NEOBalanceState) error {
if ic.Block == nil || ic.Block.Index == 0 {
return nil
}
gen, err := n.CalculateBonus(ic, &acc.Balance, acc.BalanceHeight, ic.Block.Index)
if err != nil {
return err
}
acc.BalanceHeight = ic.Block.Index
n.GAS.mint(ic, h, gen)
return nil
}
func (n *NEO) unclaimedGas(ic *interop.Context, args []stackitem.Item) stackitem.Item {
u := toUint160(args[0])
end := uint32(toBigInt(args[1]).Int64())
bs, err := ic.DAO.GetNEP5Balances(u)
if err != nil {
panic(err)
}
tr := bs.Trackers[n.ContractID]
gen, err := n.CalculateBonus(ic, &tr.Balance, tr.LastUpdatedBlock, end)
if err != nil {
panic(err)
}
return stackitem.NewBigInteger(gen)
}
func (n *NEO) getGASPerBlock(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
gas := n.GetGASPerBlock(ic.DAO, ic.Block.Index)
return stackitem.NewBigInteger(gas)
}
func (n *NEO) getGASRecordFromDAO(d dao.DAO) state.GASRecord {
var gr state.GASRecord
si := d.GetStorageItem(n.ContractID, []byte{prefixGASPerBlock})
_ = gr.FromBytes(si.Value)
return gr
}
// GetGASPerBlock returns gas generated for block with provided index.
func (n *NEO) GetGASPerBlock(d dao.DAO, index uint32) *big.Int {
var gr state.GASRecord
if n.gasPerBlockChanged.Load().(bool) {
gr = n.getGASRecordFromDAO(d)
} else {
gr = n.gasPerBlock.Load().(state.GASRecord)
}
for i := len(gr) - 1; i >= 0; i-- {
if gr[i].Index <= index {
g := gr[i].GASPerBlock
return &g
}
}
panic("contract not initialized")
}
// GetCommitteeAddress returns address of the committee.
func (n *NEO) GetCommitteeAddress() util.Uint160 {
return n.committeeHash.Load().(util.Uint160)
}
func (n *NEO) setGASPerBlock(ic *interop.Context, args []stackitem.Item) stackitem.Item {
gas := toBigInt(args[0])
ok, err := n.SetGASPerBlock(ic, ic.Block.Index+1, gas)
if err != nil {
panic(err)
}
return stackitem.NewBool(ok)
}
// SetGASPerBlock sets gas generated for blocks after index.
func (n *NEO) SetGASPerBlock(ic *interop.Context, index uint32, gas *big.Int) (bool, error) {
if gas.Sign() == -1 || gas.Cmp(big.NewInt(10*GASFactor)) == 1 {
return false, errors.New("invalid value for GASPerBlock")
}
h := n.GetCommitteeAddress()
ok, err := runtime.CheckHashedWitness(ic, h)
if err != nil || !ok {
return ok, err
}
si := ic.DAO.GetStorageItem(n.ContractID, []byte{prefixGASPerBlock})
var gr state.GASRecord
if err := gr.FromBytes(si.Value); err != nil {
return false, err
}
if len(gr) > 0 && gr[len(gr)-1].Index == index {
gr[len(gr)-1].GASPerBlock = *gas
} else {
gr = append(gr, state.GASIndexPair{
Index: index,
GASPerBlock: *gas,
})
}
n.gasPerBlockChanged.Store(true)
return true, ic.DAO.PutStorageItem(n.ContractID, []byte{prefixGASPerBlock}, &state.StorageItem{Value: gr.Bytes()})
}
// CalculateBonus calculates amount of gas generated for holding `value` NEO from start to end block.
func (n *NEO) CalculateBonus(ic *interop.Context, value *big.Int, start, end uint32) (*big.Int, error) {
if value.Sign() == 0 || start >= end {
return big.NewInt(0), nil
} else if value.Sign() < 0 {
return nil, errors.New("negative value")
}
si := ic.DAO.GetStorageItem(n.ContractID, []byte{prefixGASPerBlock})
var gr state.GASRecord
if err := gr.FromBytes(si.Value); err != nil {
return nil, err
}
var sum, tmp big.Int
for i := len(gr) - 1; i >= 0; i-- {
if gr[i].Index >= end {
continue
} else if gr[i].Index <= start {
tmp.SetInt64(int64(end - start))
tmp.Mul(&tmp, &gr[i].GASPerBlock)
sum.Add(&sum, &tmp)
break
}
tmp.SetInt64(int64(end - gr[i].Index))
tmp.Mul(&tmp, &gr[i].GASPerBlock)
sum.Add(&sum, &tmp)
end = gr[i].Index
}
res := new(big.Int).Mul(value, &sum)
res.Mul(res, tmp.SetInt64(neoHolderRewardRatio))
res.Div(res, tmp.SetInt64(100*NEOTotalSupply))
return res, nil
}
func (n *NEO) registerCandidate(ic *interop.Context, args []stackitem.Item) stackitem.Item {
pub := toPublicKey(args[0])
ok, err := runtime.CheckKeyedWitness(ic, pub)
if err != nil {
panic(err)
} else if !ok {
return stackitem.NewBool(false)
}
err = n.RegisterCandidateInternal(ic, pub)
return stackitem.NewBool(err == nil)
}
// RegisterCandidateInternal registers pub as a new candidate.
func (n *NEO) RegisterCandidateInternal(ic *interop.Context, pub *keys.PublicKey) error {
key := makeValidatorKey(pub)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
c := &candidate{Registered: true}
si = &state.StorageItem{Value: c.Bytes()}
} else {
c := new(candidate).FromBytes(si.Value)
c.Registered = true
si.Value = c.Bytes()
}
return ic.DAO.PutStorageItem(n.ContractID, key, si)
}
func (n *NEO) unregisterCandidate(ic *interop.Context, args []stackitem.Item) stackitem.Item {
pub := toPublicKey(args[0])
ok, err := runtime.CheckKeyedWitness(ic, pub)
if err != nil {
panic(err)
} else if !ok {
return stackitem.NewBool(false)
}
err = n.UnregisterCandidateInternal(ic, pub)
return stackitem.NewBool(err == nil)
}
// UnregisterCandidateInternal unregisters pub as a candidate.
func (n *NEO) UnregisterCandidateInternal(ic *interop.Context, pub *keys.PublicKey) error {
key := makeValidatorKey(pub)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
return nil
}
n.validators.Store(keys.PublicKeys(nil))
c := new(candidate).FromBytes(si.Value)
if c.Votes.Sign() == 0 {
return ic.DAO.DeleteStorageItem(n.ContractID, key)
}
c.Registered = false
si.Value = c.Bytes()
return ic.DAO.PutStorageItem(n.ContractID, key, si)
}
func (n *NEO) vote(ic *interop.Context, args []stackitem.Item) stackitem.Item {
acc := toUint160(args[0])
var pub *keys.PublicKey
if _, ok := args[1].(stackitem.Null); !ok {
pub = toPublicKey(args[1])
}
err := n.VoteInternal(ic, acc, pub)
return stackitem.NewBool(err == nil)
}
// VoteInternal votes from account h for validarors specified in pubs.
func (n *NEO) VoteInternal(ic *interop.Context, h util.Uint160, pub *keys.PublicKey) error {
ok, err := runtime.CheckHashedWitness(ic, h)
if err != nil {
return err
} else if !ok {
return errors.New("invalid signature")
}
key := makeAccountKey(h)
si := ic.DAO.GetStorageItem(n.ContractID, key)
if si == nil {
return errors.New("invalid account")
}
acc, err := state.NEOBalanceStateFromBytes(si.Value)
if err != nil {
return err
}
if (acc.VoteTo == nil) != (pub == nil) {
val := &acc.Balance
if pub == nil {
val = new(big.Int).Neg(val)
}
if err := n.modifyVoterTurnout(ic.DAO, val); err != nil {
return err
}
}
if err := n.ModifyAccountVotes(acc, ic.DAO, new(big.Int).Neg(&acc.Balance), modifyVoteOld); err != nil {
return err
}
acc.VoteTo = pub
if err := n.ModifyAccountVotes(acc, ic.DAO, &acc.Balance, modifyVoteNew); err != nil {
return err
}
si.Value = acc.Bytes()
return ic.DAO.PutStorageItem(n.ContractID, key, si)
}
const (
modifyVoteTransfer = iota
modifyVoteOld
modifyVoteNew
)
// ModifyAccountVotes modifies votes of the specified account by value (can be negative).
// typ specifies if this modify is occurring during transfer or vote (with old or new validator).
func (n *NEO) ModifyAccountVotes(acc *state.NEOBalanceState, d dao.DAO, value *big.Int, typ int) error {
n.votesChanged.Store(true)
if acc.VoteTo != nil {
key := makeValidatorKey(acc.VoteTo)
si := d.GetStorageItem(n.ContractID, key)
if si == nil {
return errors.New("invalid validator")
}
cd := new(candidate).FromBytes(si.Value)
cd.Votes.Add(&cd.Votes, value)
switch typ {
case modifyVoteOld:
if !cd.Registered && cd.Votes.Sign() == 0 {
return d.DeleteStorageItem(n.ContractID, key)
}
case modifyVoteNew:
if !cd.Registered {
return errors.New("validator must be registered")
}
}
n.validators.Store(keys.PublicKeys(nil))
si.Value = cd.Bytes()
return d.PutStorageItem(n.ContractID, key, si)
}
return nil
}
func (n *NEO) getCandidates(d dao.DAO) ([]keyWithVotes, error) {
siMap, err := d.GetStorageItemsWithPrefix(n.ContractID, []byte{prefixCandidate})
if err != nil {
return nil, err
}
arr := make([]keyWithVotes, 0, len(siMap))
for key, si := range siMap {
c := new(candidate).FromBytes(si.Value)
if c.Registered {
arr = append(arr, keyWithVotes{key, &c.Votes})
}
}
sort.Slice(arr, func(i, j int) bool { return strings.Compare(arr[i].Key, arr[j].Key) == -1 })
return arr, nil
}
// GetCandidates returns current registered validators list with keys
// and votes.
func (n *NEO) GetCandidates(d dao.DAO) ([]state.Validator, error) {
kvs, err := n.getCandidates(d)
if err != nil {
return nil, err
}
arr := make([]state.Validator, len(kvs))
for i := range kvs {
arr[i].Key, err = keys.NewPublicKeyFromBytes([]byte(kvs[i].Key), elliptic.P256())
if err != nil {
return nil, err
}
arr[i].Votes = kvs[i].Votes
}
return arr, nil
}
func (n *NEO) getCandidatesCall(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
validators, err := n.getCandidates(ic.DAO)
if err != nil {
panic(err)
}
arr := make([]stackitem.Item, len(validators))
for i := range validators {
arr[i] = stackitem.NewStruct([]stackitem.Item{
stackitem.NewByteArray([]byte(validators[i].Key)),
stackitem.NewBigInteger(validators[i].Votes),
})
}
return stackitem.NewArray(arr)
}
// ComputeNextBlockValidators returns an actual list of current validators.
func (n *NEO) ComputeNextBlockValidators(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
if vals := n.validators.Load().(keys.PublicKeys); vals != nil {
return vals.Copy(), nil
}
result, err := n.ComputeCommitteeMembers(bc, d)
if err != nil {
return nil, err
}
result = result[:bc.GetConfig().ValidatorsCount]
sort.Sort(result)
n.validators.Store(result)
return result, nil
}
func (n *NEO) getCommittee(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
pubs := n.GetCommitteeMembers()
sort.Sort(pubs)
return pubsToArray(pubs)
}
func (n *NEO) modifyVoterTurnout(d dao.DAO, amount *big.Int) error {
key := []byte{prefixVotersCount}
si := d.GetStorageItem(n.ContractID, key)
if si == nil {
return errors.New("voters count not found")
}
votersCount := bigint.FromBytes(si.Value)
votersCount.Add(votersCount, amount)
si.Value = bigint.ToBytes(votersCount)
return d.PutStorageItem(n.ContractID, key, si)
}
// GetCommitteeMembers returns public keys of nodes in committee using cached value.
func (n *NEO) GetCommitteeMembers() keys.PublicKeys {
return n.committee.Load().(keys.PublicKeys).Copy()
}
// ComputeCommitteeMembers returns public keys of nodes in committee.
func (n *NEO) ComputeCommitteeMembers(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
key := []byte{prefixVotersCount}
si := d.GetStorageItem(n.ContractID, key)
if si == nil {
return nil, errors.New("voters count not found")
}
votersCount := bigint.FromBytes(si.Value)
// votersCount / totalSupply must be >= 0.2
votersCount.Mul(votersCount, big.NewInt(effectiveVoterTurnout))
voterTurnout := votersCount.Div(votersCount, n.getTotalSupply(d))
if voterTurnout.Sign() != 1 {
pubs := bc.GetStandByCommittee()
return pubs, nil
}
cs, err := n.getCandidates(d)
if err != nil {
return nil, err
}
sbVals := bc.GetStandByCommittee()
count := len(sbVals)
if len(cs) < count {
return sbVals, nil
}
sort.Slice(cs, func(i, j int) bool {
// The most-voted validators should end up in the front of the list.
cmp := cs[i].Votes.Cmp(cs[j].Votes)
if cmp != 0 {
return cmp > 0
}
// Ties are broken with public keys.
return strings.Compare(cs[i].Key, cs[j].Key) == -1
})
pubs := make(keys.PublicKeys, count)
for i := range pubs {
pubs[i], err = keys.NewPublicKeyFromBytes([]byte(cs[i].Key), elliptic.P256())
if err != nil {
return nil, err
}
}
return pubs, nil
}
func (n *NEO) getNextBlockValidators(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
result := n.GetNextBlockValidatorsInternal()
return pubsToArray(result)
}
// GetNextBlockValidatorsInternal returns next block validators.
func (n *NEO) GetNextBlockValidatorsInternal() keys.PublicKeys {
return n.nextValidators.Load().(keys.PublicKeys).Copy()
}
func pubsToArray(pubs keys.PublicKeys) stackitem.Item {
arr := make([]stackitem.Item, len(pubs))
for i := range pubs {
arr[i] = stackitem.NewByteArray(pubs[i].Bytes())
}
return stackitem.NewArray(arr)
}
func toPublicKey(s stackitem.Item) *keys.PublicKey {
buf, err := s.TryBytes()
if err != nil {
panic(err)
}
pub := new(keys.PublicKey)
if err := pub.DecodeBytes(buf); err != nil {
panic(err)
}
return pub
}