mirror of
https://github.com/nspcc-dev/neo-go.git
synced 2024-11-23 13:38:35 +00:00
567 lines
16 KiB
Go
567 lines
16 KiB
Go
package native
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import (
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"crypto/elliptic"
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"errors"
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"math/big"
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"sort"
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"strings"
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"sync/atomic"
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"github.com/nspcc-dev/neo-go/pkg/core/blockchainer"
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"github.com/nspcc-dev/neo-go/pkg/core/dao"
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"github.com/nspcc-dev/neo-go/pkg/core/interop"
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"github.com/nspcc-dev/neo-go/pkg/core/interop/runtime"
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"github.com/nspcc-dev/neo-go/pkg/core/state"
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"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
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"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
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"github.com/nspcc-dev/neo-go/pkg/smartcontract"
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"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
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"github.com/nspcc-dev/neo-go/pkg/util"
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"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
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)
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// NEO represents NEO native contract.
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type NEO struct {
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nep5TokenNative
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GAS *GAS
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votesChanged atomic.Value
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nextValidators atomic.Value
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validators atomic.Value
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}
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// keyWithVotes is a serialized key with votes balance. It's not deserialized
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// because some uses of it imply serialized-only usage and converting to
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// PublicKey is quite expensive.
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type keyWithVotes struct {
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Key string
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Votes *big.Int
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}
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const (
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neoName = "NEO"
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neoContractID = -1
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// NEOTotalSupply is the total amount of NEO in the system.
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NEOTotalSupply = 100000000
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// prefixCandidate is a prefix used to store validator's data.
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prefixCandidate = 33
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// prefixVotersCount is a prefix for storing total amount of NEO of voters.
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prefixVotersCount = 1
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// effectiveVoterTurnout represents minimal ratio of total supply to total amount voted value
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// which is require to use non-standby validators.
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effectiveVoterTurnout = 5
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)
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var (
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// nextValidatorsKey is a key used to store validators for the
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// next block.
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nextValidatorsKey = []byte{14}
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)
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// makeValidatorKey creates a key from account script hash.
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func makeValidatorKey(key *keys.PublicKey) []byte {
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b := key.Bytes()
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// Don't create a new buffer.
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b = append(b, 0)
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copy(b[1:], b[0:])
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b[0] = prefixCandidate
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return b
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}
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// NewNEO returns NEO native contract.
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func NewNEO() *NEO {
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n := &NEO{}
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nep5 := newNEP5Native(neoName)
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nep5.symbol = "neo"
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nep5.decimals = 0
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nep5.factor = 1
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nep5.onPersist = chainOnPersist(nep5.OnPersist, n.OnPersist)
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nep5.incBalance = n.increaseBalance
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nep5.ContractID = neoContractID
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n.nep5TokenNative = *nep5
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n.votesChanged.Store(true)
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n.nextValidators.Store(keys.PublicKeys(nil))
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n.validators.Store(keys.PublicKeys(nil))
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onp := n.Methods["onPersist"]
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onp.Func = getOnPersistWrapper(n.onPersist)
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n.Methods["onPersist"] = onp
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desc := newDescriptor("unclaimedGas", smartcontract.IntegerType,
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manifest.NewParameter("account", smartcontract.Hash160Type),
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manifest.NewParameter("end", smartcontract.IntegerType))
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md := newMethodAndPrice(n.unclaimedGas, 3000000, smartcontract.AllowStates)
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n.AddMethod(md, desc, true)
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desc = newDescriptor("registerCandidate", smartcontract.BoolType,
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manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
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md = newMethodAndPrice(n.registerCandidate, 5000000, smartcontract.AllowModifyStates)
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n.AddMethod(md, desc, false)
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desc = newDescriptor("unregisterCandidate", smartcontract.BoolType,
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manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
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md = newMethodAndPrice(n.unregisterCandidate, 5000000, smartcontract.AllowModifyStates)
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n.AddMethod(md, desc, false)
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desc = newDescriptor("vote", smartcontract.BoolType,
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manifest.NewParameter("account", smartcontract.Hash160Type),
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manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
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md = newMethodAndPrice(n.vote, 500000000, smartcontract.AllowModifyStates)
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n.AddMethod(md, desc, false)
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desc = newDescriptor("getCandidates", smartcontract.ArrayType)
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md = newMethodAndPrice(n.getCandidatesCall, 100000000, smartcontract.AllowStates)
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n.AddMethod(md, desc, true)
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desc = newDescriptor("getСommittee", smartcontract.ArrayType)
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md = newMethodAndPrice(n.getCommittee, 100000000, smartcontract.AllowStates)
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n.AddMethod(md, desc, true)
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desc = newDescriptor("getValidators", smartcontract.ArrayType)
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md = newMethodAndPrice(n.getValidators, 100000000, smartcontract.AllowStates)
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n.AddMethod(md, desc, true)
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desc = newDescriptor("getNextBlockValidators", smartcontract.ArrayType)
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md = newMethodAndPrice(n.getNextBlockValidators, 100000000, smartcontract.AllowStates)
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n.AddMethod(md, desc, true)
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return n
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}
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// Initialize initializes NEO contract.
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func (n *NEO) Initialize(ic *interop.Context) error {
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if err := n.nep5TokenNative.Initialize(ic); err != nil {
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return err
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}
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if n.nep5TokenNative.getTotalSupply(ic.DAO).Sign() != 0 {
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return errors.New("already initialized")
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}
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h, err := getStandbyValidatorsHash(ic)
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if err != nil {
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return err
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}
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n.mint(ic, h, big.NewInt(NEOTotalSupply))
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err = ic.DAO.PutStorageItem(n.ContractID, []byte{prefixVotersCount}, &state.StorageItem{Value: []byte{}})
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if err != nil {
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return err
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}
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return nil
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}
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// OnPersist implements Contract interface.
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func (n *NEO) OnPersist(ic *interop.Context) error {
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if !n.votesChanged.Load().(bool) {
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return nil
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}
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pubs, err := n.GetValidatorsInternal(ic.Chain, ic.DAO)
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if err != nil {
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return err
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}
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prev := n.nextValidators.Load().(keys.PublicKeys)
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if len(prev) == len(pubs) {
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var needUpdate bool
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for i := range pubs {
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if !pubs[i].Equal(prev[i]) {
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needUpdate = true
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break
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}
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}
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if !needUpdate {
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return nil
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}
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}
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n.votesChanged.Store(false)
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n.nextValidators.Store(pubs)
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si := new(state.StorageItem)
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si.Value = pubs.Bytes()
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return ic.DAO.PutStorageItem(n.ContractID, nextValidatorsKey, si)
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}
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func (n *NEO) increaseBalance(ic *interop.Context, h util.Uint160, si *state.StorageItem, amount *big.Int) error {
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acc, err := state.NEOBalanceStateFromBytes(si.Value)
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if err != nil {
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return err
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}
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if amount.Sign() == -1 && acc.Balance.Cmp(new(big.Int).Neg(amount)) == -1 {
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return errors.New("insufficient funds")
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}
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if err := n.distributeGas(ic, h, acc); err != nil {
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return err
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}
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if amount.Sign() == 0 {
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si.Value = acc.Bytes()
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return nil
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}
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if err := n.ModifyAccountVotes(acc, ic.DAO, amount, modifyVoteTransfer); err != nil {
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return err
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}
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if acc.VoteTo != nil {
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if err := n.modifyVoterTurnout(ic.DAO, amount); err != nil {
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return err
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}
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}
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acc.Balance.Add(&acc.Balance, amount)
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if acc.Balance.Sign() != 0 {
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si.Value = acc.Bytes()
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} else {
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si.Value = nil
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}
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return nil
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}
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func (n *NEO) distributeGas(ic *interop.Context, h util.Uint160, acc *state.NEOBalanceState) error {
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if ic.Block == nil || ic.Block.Index == 0 {
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return nil
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}
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gen := ic.Chain.CalculateClaimable(&acc.Balance, acc.BalanceHeight, ic.Block.Index)
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acc.BalanceHeight = ic.Block.Index
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n.GAS.mint(ic, h, gen)
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return nil
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}
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func (n *NEO) unclaimedGas(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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u := toUint160(args[0])
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end := uint32(toBigInt(args[1]).Int64())
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bs, err := ic.DAO.GetNEP5Balances(u)
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if err != nil {
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panic(err)
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}
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tr := bs.Trackers[n.ContractID]
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gen := ic.Chain.CalculateClaimable(&tr.Balance, tr.LastUpdatedBlock, end)
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return stackitem.NewBigInteger(gen)
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}
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func (n *NEO) registerCandidate(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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pub := toPublicKey(args[0])
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ok, err := runtime.CheckKeyedWitness(ic, pub)
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if err != nil {
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panic(err)
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} else if !ok {
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return stackitem.NewBool(false)
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}
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err = n.RegisterCandidateInternal(ic, pub)
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return stackitem.NewBool(err == nil)
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}
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// RegisterCandidateInternal registers pub as a new candidate.
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func (n *NEO) RegisterCandidateInternal(ic *interop.Context, pub *keys.PublicKey) error {
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key := makeValidatorKey(pub)
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si := ic.DAO.GetStorageItem(n.ContractID, key)
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if si == nil {
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c := &candidate{Registered: true}
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si = &state.StorageItem{Value: c.Bytes()}
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} else {
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c := new(candidate).FromBytes(si.Value)
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c.Registered = true
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si.Value = c.Bytes()
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}
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return ic.DAO.PutStorageItem(n.ContractID, key, si)
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}
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func (n *NEO) unregisterCandidate(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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pub := toPublicKey(args[0])
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ok, err := runtime.CheckKeyedWitness(ic, pub)
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if err != nil {
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panic(err)
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} else if !ok {
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return stackitem.NewBool(false)
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}
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err = n.UnregisterCandidateInternal(ic, pub)
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return stackitem.NewBool(err == nil)
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}
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// UnregisterCandidateInternal unregisters pub as a candidate.
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func (n *NEO) UnregisterCandidateInternal(ic *interop.Context, pub *keys.PublicKey) error {
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key := makeValidatorKey(pub)
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si := ic.DAO.GetStorageItem(n.ContractID, key)
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if si == nil {
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return nil
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}
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n.validators.Store(keys.PublicKeys(nil))
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c := new(candidate).FromBytes(si.Value)
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if c.Votes.Sign() == 0 {
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return ic.DAO.DeleteStorageItem(n.ContractID, key)
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}
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c.Registered = false
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si.Value = c.Bytes()
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return ic.DAO.PutStorageItem(n.ContractID, key, si)
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}
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func (n *NEO) vote(ic *interop.Context, args []stackitem.Item) stackitem.Item {
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acc := toUint160(args[0])
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var pub *keys.PublicKey
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if _, ok := args[1].(stackitem.Null); !ok {
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pub = toPublicKey(args[1])
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}
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err := n.VoteInternal(ic, acc, pub)
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return stackitem.NewBool(err == nil)
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}
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// VoteInternal votes from account h for validarors specified in pubs.
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func (n *NEO) VoteInternal(ic *interop.Context, h util.Uint160, pub *keys.PublicKey) error {
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ok, err := runtime.CheckHashedWitness(ic, h)
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if err != nil {
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return err
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} else if !ok {
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return errors.New("invalid signature")
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}
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key := makeAccountKey(h)
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si := ic.DAO.GetStorageItem(n.ContractID, key)
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if si == nil {
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return errors.New("invalid account")
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}
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acc, err := state.NEOBalanceStateFromBytes(si.Value)
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if err != nil {
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return err
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}
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if (acc.VoteTo == nil) != (pub == nil) {
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val := &acc.Balance
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if pub == nil {
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val = new(big.Int).Neg(val)
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}
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if err := n.modifyVoterTurnout(ic.DAO, val); err != nil {
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return err
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}
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}
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if err := n.ModifyAccountVotes(acc, ic.DAO, new(big.Int).Neg(&acc.Balance), modifyVoteOld); err != nil {
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return err
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}
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acc.VoteTo = pub
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if err := n.ModifyAccountVotes(acc, ic.DAO, &acc.Balance, modifyVoteNew); err != nil {
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return err
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}
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si.Value = acc.Bytes()
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return ic.DAO.PutStorageItem(n.ContractID, key, si)
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}
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const (
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modifyVoteTransfer = iota
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modifyVoteOld
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modifyVoteNew
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)
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// ModifyAccountVotes modifies votes of the specified account by value (can be negative).
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// typ specifies if this modify is occurring during transfer or vote (with old or new validator).
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func (n *NEO) ModifyAccountVotes(acc *state.NEOBalanceState, d dao.DAO, value *big.Int, typ int) error {
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n.votesChanged.Store(true)
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if acc.VoteTo != nil {
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key := makeValidatorKey(acc.VoteTo)
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si := d.GetStorageItem(n.ContractID, key)
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if si == nil {
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return errors.New("invalid validator")
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}
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cd := new(candidate).FromBytes(si.Value)
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cd.Votes.Add(&cd.Votes, value)
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switch typ {
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case modifyVoteOld:
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if !cd.Registered && cd.Votes.Sign() == 0 {
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return d.DeleteStorageItem(n.ContractID, key)
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}
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case modifyVoteNew:
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if !cd.Registered {
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return errors.New("validator must be registered")
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}
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}
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n.validators.Store(keys.PublicKeys(nil))
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si.Value = cd.Bytes()
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return d.PutStorageItem(n.ContractID, key, si)
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}
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return nil
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}
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func (n *NEO) getCandidates(d dao.DAO) ([]keyWithVotes, error) {
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siMap, err := d.GetStorageItemsWithPrefix(n.ContractID, []byte{prefixCandidate})
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if err != nil {
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return nil, err
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}
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arr := make([]keyWithVotes, 0, len(siMap))
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for key, si := range siMap {
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c := new(candidate).FromBytes(si.Value)
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if c.Registered {
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arr = append(arr, keyWithVotes{key, &c.Votes})
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}
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}
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sort.Slice(arr, func(i, j int) bool { return strings.Compare(arr[i].Key, arr[j].Key) == -1 })
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return arr, nil
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}
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// GetCandidates returns current registered validators list with keys
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// and votes.
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func (n *NEO) GetCandidates(d dao.DAO) ([]state.Validator, error) {
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kvs, err := n.getCandidates(d)
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if err != nil {
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return nil, err
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}
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arr := make([]state.Validator, len(kvs))
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for i := range kvs {
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arr[i].Key, err = keys.NewPublicKeyFromBytes([]byte(kvs[i].Key), elliptic.P256())
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if err != nil {
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return nil, err
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}
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arr[i].Votes = kvs[i].Votes
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}
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return arr, nil
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}
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func (n *NEO) getCandidatesCall(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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validators, err := n.getCandidates(ic.DAO)
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if err != nil {
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panic(err)
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}
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arr := make([]stackitem.Item, len(validators))
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for i := range validators {
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arr[i] = stackitem.NewStruct([]stackitem.Item{
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stackitem.NewByteArray([]byte(validators[i].Key)),
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stackitem.NewBigInteger(validators[i].Votes),
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})
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}
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return stackitem.NewArray(arr)
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}
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// GetValidatorsInternal returns a list of current validators.
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func (n *NEO) GetValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
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if vals := n.validators.Load().(keys.PublicKeys); vals != nil {
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return vals.Copy(), nil
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}
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result, err := n.GetCommitteeMembers(bc, d)
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if err != nil {
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return nil, err
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}
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count := bc.GetConfig().ValidatorsCount
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if len(result) < count {
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count = len(result)
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}
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result = result[:count]
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sort.Sort(result)
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n.validators.Store(result)
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return result, nil
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}
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func (n *NEO) getValidators(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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result, err := n.GetValidatorsInternal(ic.Chain, ic.DAO)
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if err != nil {
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panic(err)
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}
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return pubsToArray(result)
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}
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func (n *NEO) getCommittee(ic *interop.Context, _ []stackitem.Item) stackitem.Item {
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pubs, err := n.GetCommitteeMembers(ic.Chain, ic.DAO)
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if err != nil {
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panic(err)
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}
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sort.Sort(pubs)
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return pubsToArray(pubs)
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}
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func (n *NEO) modifyVoterTurnout(d dao.DAO, amount *big.Int) error {
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key := []byte{prefixVotersCount}
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si := d.GetStorageItem(n.ContractID, key)
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if si == nil {
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return errors.New("voters count not found")
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}
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votersCount := bigint.FromBytes(si.Value)
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votersCount.Add(votersCount, amount)
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si.Value = bigint.ToBytes(votersCount)
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return d.PutStorageItem(n.ContractID, key, si)
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}
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// GetCommitteeMembers returns public keys of nodes in committee.
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func (n *NEO) GetCommitteeMembers(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
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key := []byte{prefixVotersCount}
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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 {
|
|
return bc.GetStandByCommittee(), 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, err := n.getNextBlockValidatorsInternal(ic.Chain, ic.DAO)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return pubsToArray(result)
|
|
}
|
|
|
|
// GetNextBlockValidatorsInternal returns next block validators.
|
|
func (n *NEO) GetNextBlockValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
|
|
pubs, err := n.getNextBlockValidatorsInternal(bc, d)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return pubs.Copy(), nil
|
|
}
|
|
|
|
// getNextBlockValidatorsInternal returns next block validators.
|
|
func (n *NEO) getNextBlockValidatorsInternal(bc blockchainer.Blockchainer, d dao.DAO) (keys.PublicKeys, error) {
|
|
si := d.GetStorageItem(n.ContractID, nextValidatorsKey)
|
|
if si == nil {
|
|
return n.GetValidatorsInternal(bc, d)
|
|
}
|
|
pubs := keys.PublicKeys{}
|
|
err := pubs.DecodeBytes(si.Value)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return pubs, nil
|
|
}
|
|
|
|
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
|
|
}
|