// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package core
import (
"fmt"
"math/big"
"math/rand"
"time"
coreTypes "github.com/dexon-foundation/dexon-consensus/core/types"
"github.com/dexon-foundation/dexon/common"
"github.com/dexon-foundation/dexon/consensus"
"github.com/dexon-foundation/dexon/core/state"
"github.com/dexon-foundation/dexon/core/types"
"github.com/dexon-foundation/dexon/core/vm"
"github.com/dexon-foundation/dexon/ethdb"
"github.com/dexon-foundation/dexon/params"
"github.com/dexon-foundation/dexon/rlp"
)
func init() {
rand.Seed(time.Now().UTC().UnixNano())
}
// DexonBlockGen creates blocks for testing.
// See GenerateChain for a detailed explanation.
type DexonBlockGen struct {
i int
parent *types.Block
chain []*types.Block
header *types.Header
statedb *state.StateDB
dirtyNonce map[common.Address]uint64
position coreTypes.Position
gasPool *GasPool
txs []*types.Transaction
receipts []*types.Receipt
config *params.ChainConfig
engine consensus.Engine
}
// SetCoinbase sets the coinbase of the generated block.
// It can be called at most once.
func (b *DexonBlockGen) SetCoinbase(addr common.Address) {
if b.gasPool != nil {
if len(b.txs) > 0 {
panic("coinbase must be set before adding transactions")
}
panic("coinbase can only be set once")
}
b.header.Coinbase = addr
b.gasPool = new(GasPool).AddGas(b.header.GasLimit)
}
// SetExtra sets the extra data field of the generated block.
func (b *DexonBlockGen) SetExtra(data []byte) {
b.header.Extra = data
}
// SetNonce sets the nonce field of the generated block.
func (b *DexonBlockGen) SetNonce(nonce types.BlockNonce) {
b.header.Nonce = nonce
}
func (b *DexonBlockGen) SetPosition(position coreTypes.Position) {
b.position = position
}
// AddTx adds a transaction to the generated block. If no coinbase has
// been set, the block's coinbase is set to the zero address.
//
// AddTx panics if the transaction cannot be executed. In addition to
// the protocol-imposed limitations (gas limit, etc.), there are some
// further limitations on the content of transactions that can be
// added. If contract code relies on the BLOCKHASH instruction,
// the block in chain will be returned.
func (b *DexonBlockGen) AddTx(tx *types.Transaction) {
// TODO: check nonce and maintain nonce.
b.txs = append(b.txs, tx)
}
func (b *DexonBlockGen) PreparePayload() []byte {
return nil
}
func (b *DexonBlockGen) ProcessTransactions(c ChainContext) {
if b.gasPool == nil {
b.SetCoinbase(common.Address{})
}
for _, tx := range b.txs {
b.statedb.Prepare(tx.Hash(), common.Hash{}, len(b.txs))
// TODO: fix the chain context parameter
receipt, _, err := ApplyTransaction(b.config, c, &b.header.Coinbase, b.gasPool, b.statedb, b.header, tx, &b.header.GasUsed, vm.Config{})
if err != nil {
panic(err)
}
b.receipts = append(b.receipts, receipt)
}
}
// Number returns the block number of the block being generated.
func (b *DexonBlockGen) Number() *big.Int {
return new(big.Int).Set(b.header.Number)
}
// AddUncheckedReceipt forcefully adds a receipts to the block without a
// backing transaction.
//
// AddUncheckedReceipt will cause consensus failures when used during real
// chain processing. This is best used in conjunction with raw block insertion.
func (b *DexonBlockGen) AddUncheckedReceipt(receipt *types.Receipt) {
b.receipts = append(b.receipts, receipt)
}
// TxNonce returns the next valid transaction nonce for the
// account at addr. It panics if the account does not exist.
func (b *DexonBlockGen) TxNonce(addr common.Address) uint64 {
if !b.statedb.Exist(addr) {
panic("account does not exist")
}
if nonce, exists := b.dirtyNonce[addr]; exists {
return nonce
}
return b.statedb.GetNonce(addr)
}
// PrevBlock returns a previously generated block by number. It panics if
// num is greater or equal to the number of the block being generated.
// For index -1, PrevBlock returns the parent block given to GenerateChain.
func (b *DexonBlockGen) PrevBlock(index int) *types.Block {
if index >= b.i {
panic(fmt.Errorf("block index %d out of range (%d,%d)", index, -1, b.i))
}
if index == -1 {
return b.parent
}
return b.chain[index]
}
func GenerateDexonChain(config *params.ChainConfig, parent *types.Block, engine consensus.Engine, db ethdb.Database, n int, gen func(int, *DexonBlockGen)) ([]*types.Block, []types.Receipts) {
if config == nil {
config = params.TestChainConfig
}
if engine == nil {
panic("engine is nil")
}
blocks, receipts := make(types.Blocks, n), make([]types.Receipts, n)
chain := &fakeDexonChain{
config: config,
engine: engine,
genesis: parent,
db: db,
headersByNumber: make(map[uint64]*types.Header),
roundHeight: make(map[uint64]uint64),
}
genblock := func(i int, parent *types.Block, statedb *state.StateDB) (*types.Block, types.Receipts) {
b := &DexonBlockGen{i: i, chain: blocks, parent: parent, statedb: statedb, config: config, engine: engine}
b.header = makeDexonHeader(chain, parent, statedb, b.engine)
// Execute any user modifications to the block
if gen != nil {
gen(i, b)
}
b.header.DexconMeta = makeDexconMeta(b, parent)
// sign tsig to create dexcon, prepare witness
b.engine.Prepare(chain, b.header)
// Run EVM and finalize the block.
b.ProcessTransactions(chain)
// Finalize and seal the block
block, _ := b.engine.Finalize(chain, b.header, statedb, b.txs, nil, b.receipts)
// Write state changes to db
root, err := statedb.Commit(config.IsEIP158(b.header.Number))
if err != nil {
panic(fmt.Sprintf("state write error: %v", err))
}
if err := statedb.Database().TrieDB().Commit(root, false); err != nil {
panic(fmt.Sprintf("trie write error: %v", err))
}
return block, b.receipts
}
for i := 0; i < n; i++ {
statedb, err := state.New(parent.Root(), state.NewDatabase(db))
if err != nil {
panic(err)
}
block, receipt := genblock(i, parent, statedb)
blocks[i] = block
receipts[i] = receipt
parent = block
chain.InsertBlock(block)
}
return blocks, receipts
}
func makeDexonHeader(chain consensus.ChainReader, parent *types.Block, state *state.StateDB, engine consensus.Engine) *types.Header {
var time uint64
if parent.Time() == 0 {
time = 10
} else {
time = parent.Time() + 10 // block time is fixed at 10 seconds
}
return &types.Header{
Root: state.IntermediateRoot(chain.Config().IsEIP158(parent.Number())),
ParentHash: parent.Hash(),
Coinbase: parent.Coinbase(),
Difficulty: new(big.Int).Add(parent.Difficulty(), common.Big1),
GasLimit: chain.Config().Dexcon.BlockGasLimit,
Number: new(big.Int).Add(parent.Number(), common.Big1),
Time: time,
}
}
// Setup DexconMeata skeleton
func makeDexconMeta(b *DexonBlockGen, parent *types.Block) []byte {
// Setup witness
h := parent.Number().Int64() - rand.Int63n(6)
if h < 0 {
h = 0
}
witnessedBlock := b.chain[h]
if witnessedBlock == nil {
witnessedBlock = parent
}
witnessedBlockHash := witnessedBlock.Hash()
data, err := rlp.EncodeToBytes(&witnessedBlockHash)
if err != nil {
panic(err)
}
block := coreTypes.Block{
Position: b.position,
Witness: coreTypes.Witness{
Height: witnessedBlock.NumberU64(),
Data: data,
},
}
dexconMeta, err := rlp.EncodeToBytes(&block)
if err != nil {
panic(err)
}
return dexconMeta
}
type fakeDexonChain struct {
config *params.ChainConfig
engine consensus.Engine
db ethdb.Database
genesis *types.Block
headersByNumber map[uint64]*types.Header
roundHeight map[uint64]uint64
}
func (f *fakeDexonChain) InsertBlock(block *types.Block) {
f.headersByNumber[block.NumberU64()] = block.Header()
if _, exists := f.roundHeight[block.Round()]; !exists {
f.roundHeight[block.Round()] = block.NumberU64()
}
}
// Config returns the chain configuration.
func (f *fakeDexonChain) Config() *params.ChainConfig { return f.config }
func (f *fakeDexonChain) Engine() consensus.Engine { return f.engine }
func (f *fakeDexonChain) CurrentHeader() *types.Header { return nil }
func (f *fakeDexonChain) GetHeaderByHash(hash common.Hash) *types.Header { return nil }
func (f *fakeDexonChain) GetHeader(hash common.Hash, number uint64) *types.Header { return nil }
func (f *fakeDexonChain) GetBlock(hash common.Hash, number uint64) *types.Block { return nil }
func (f *fakeDexonChain) GetHeaderByNumber(number uint64) *types.Header {
if number == 0 {
return f.genesis.Header()
}
return f.headersByNumber[number]
}
func (f *fakeDexonChain) StateAt(hash common.Hash) (*state.StateDB, error) {
return state.New(hash, state.NewDatabase(f.db))
}
func (f *fakeDexonChain) GetRoundHeight(round uint64) (uint64, bool) {
if round == 0 {
return 0, true
}
height, ok := f.roundHeight[round]
return height, ok
}