package core
import (
"fmt"
"math/big"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/pow"
"github.com/ethereum/go-ethereum/state"
)
// So we can generate blocks easily
type FakePow struct{}
func (f FakePow) Search(block pow.Block, stop <-chan struct{}) ([]byte, []byte, []byte) {
return nil, nil, nil
}
func (f FakePow) Verify(block pow.Block) bool { return true }
func (f FakePow) GetHashrate() int64 { return 0 }
func (f FakePow) Turbo(bool) {}
// So we can deterministically seed different blockchains
var (
CanonicalSeed = 1
ForkSeed = 2
)
// Utility functions for making chains on the fly
// Exposed for sake of testing from other packages (eg. go-ethash)
func NewBlockFromParent(addr []byte, parent *types.Block) *types.Block {
return newBlockFromParent(addr, parent)
}
func MakeBlock(bman *BlockProcessor, parent *types.Block, i int, db ethutil.Database, seed int) *types.Block {
return makeBlock(bman, parent, i, db, seed)
}
func MakeChain(bman *BlockProcessor, parent *types.Block, max int, db ethutil.Database, seed int) types.Blocks {
return makeChain(bman, parent, max, db, seed)
}
func NewChainMan(block *types.Block, eventMux *event.TypeMux, db ethutil.Database) *ChainManager {
return newChainManager(block, eventMux, db)
}
func NewBlockProc(db ethutil.Database, txpool *TxPool, cman *ChainManager, eventMux *event.TypeMux) *BlockProcessor {
return newBlockProcessor(db, txpool, cman, eventMux)
}
func NewCanonical(n int, db ethutil.Database) (*BlockProcessor, error) {
return newCanonical(n, db)
}
// block time is fixed at 10 seconds
func newBlockFromParent(addr []byte, parent *types.Block) *types.Block {
block := types.NewBlock(parent.Hash(), addr, parent.Root(), ethutil.BigPow(2, 32), nil, "")
block.SetUncles(nil)
block.SetTransactions(nil)
block.SetReceipts(nil)
header := block.Header()
header.Difficulty = CalcDifficulty(block, parent)
header.Number = new(big.Int).Add(parent.Header().Number, ethutil.Big1)
header.Time = parent.Header().Time + 10
header.GasLimit = CalcGasLimit(parent, block)
block.Td = parent.Td
return block
}
// Actually make a block by simulating what miner would do
// we seed chains by the first byte of the coinbase
func makeBlock(bman *BlockProcessor, parent *types.Block, i int, db ethutil.Database, seed int) *types.Block {
addr := ethutil.LeftPadBytes([]byte{byte(i)}, 20)
addr[0] = byte(seed)
block := newBlockFromParent(addr, parent)
state := state.New(block.Root(), db)
cbase := state.GetOrNewStateObject(addr)
cbase.SetGasPool(CalcGasLimit(parent, block))
cbase.AddBalance(BlockReward)
state.Update(ethutil.Big0)
block.SetRoot(state.Root())
return block
}
// Make a chain with real blocks
// Runs ProcessWithParent to get proper state roots
func makeChain(bman *BlockProcessor, parent *types.Block, max int, db ethutil.Database, seed int) types.Blocks {
bman.bc.currentBlock = parent
blocks := make(types.Blocks, max)
for i := 0; i < max; i++ {
block := makeBlock(bman, parent, i, db, seed)
td, err := bman.processWithParent(block, parent)
if err != nil {
fmt.Println("process with parent failed", err)
panic(err)
}
block.Td = td
blocks[i] = block
parent = block
}
return blocks
}
// Create a new chain manager starting from given block
// Effectively a fork factory
func newChainManager(block *types.Block, eventMux *event.TypeMux, db ethutil.Database) *ChainManager {
bc := &ChainManager{db: db, genesisBlock: GenesisBlock(db), eventMux: eventMux}
if block == nil {
bc.Reset()
} else {
bc.currentBlock = block
bc.td = block.Td
}
return bc
}
// block processor with fake pow
func newBlockProcessor(db ethutil.Database, txpool *TxPool, cman *ChainManager, eventMux *event.TypeMux) *BlockProcessor {
bman := NewBlockProcessor(db, FakePow{}, txpool, newChainManager(nil, eventMux, db), eventMux)
return bman
}
// Make a new, deterministic canonical chain by running InsertChain
// on result of makeChain
func newCanonical(n int, db ethutil.Database) (*BlockProcessor, error) {
eventMux := &event.TypeMux{}
txpool := NewTxPool(eventMux)
bman := newBlockProcessor(db, txpool, newChainManager(nil, eventMux, db), eventMux)
bman.bc.SetProcessor(bman)
parent := bman.bc.CurrentBlock()
if n == 0 {
return bman, nil
}
lchain := makeChain(bman, parent, n, db, CanonicalSeed)
err := bman.bc.InsertChain(lchain)
return bman, err
}