path: root/core/genesis.go

// Copyright 2014 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 (
    "compress/bzip2"
    "compress/gzip"
    "encoding/base64"
    "encoding/json"
    "fmt"
    "io"
    "io/ioutil"
    "math/big"
    "strings"

    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/core/state"
    "github.com/ethereum/go-ethereum/core/types"
    "github.com/ethereum/go-ethereum/ethdb"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/logger/glog"
    "github.com/ethereum/go-ethereum/params"
)

// WriteGenesisBlock writes the genesis block to the database as block number 0
func WriteGenesisBlock(chainDb ethdb.Database, reader io.Reader) (*types.Block, error) {
    contents, err := ioutil.ReadAll(reader)
    if err != nil {
        return nil, err
    }

    var genesis struct {
        ChainConfig *params.ChainConfig `json:"config"`
        Nonce       string
        Timestamp   string
        ParentHash  string
        ExtraData   string
        GasLimit    string
        Difficulty  string
        Mixhash     string
        Coinbase    string
        Alloc       map[string]struct {
            Code    string
            Storage map[string]string
            Balance string
        }
    }

    if err := json.Unmarshal(contents, &genesis); err != nil {
        return nil, err
    }

    // creating with empty hash always works
    statedb, _ := state.New(common.Hash{}, chainDb)
    for addr, account := range genesis.Alloc {
        address := common.HexToAddress(addr)
        statedb.AddBalance(address, common.String2Big(account.Balance))
        statedb.SetCode(address, common.Hex2Bytes(account.Code))
        for key, value := range account.Storage {
            statedb.SetState(address, common.HexToHash(key), common.HexToHash(value))
        }
    }
    root, stateBatch := statedb.CommitBatch(false)

    difficulty := common.String2Big(genesis.Difficulty)
    block := types.NewBlock(&types.Header{
        Nonce:      types.EncodeNonce(common.String2Big(genesis.Nonce).Uint64()),
        Time:       common.String2Big(genesis.Timestamp),
        ParentHash: common.HexToHash(genesis.ParentHash),
        Extra:      common.FromHex(genesis.ExtraData),
        GasLimit:   common.String2Big(genesis.GasLimit),
        Difficulty: difficulty,
        MixDigest:  common.HexToHash(genesis.Mixhash),
        Coinbase:   common.HexToAddress(genesis.Coinbase),
        Root:       root,
    }, nil, nil, nil)

    if block := GetBlock(chainDb, block.Hash(), block.NumberU64()); block != nil {
        glog.V(logger.Info).Infoln("Genesis block already in chain. Writing canonical number")
        err := WriteCanonicalHash(chainDb, block.Hash(), block.NumberU64())
        if err != nil {
            return nil, err
        }
        return block, nil
    }

    if err := stateBatch.Write(); err != nil {
        return nil, fmt.Errorf("cannot write state: %v", err)
    }
    if err := WriteTd(chainDb, block.Hash(), block.NumberU64(), difficulty); err != nil {
        return nil, err
    }
    if err := WriteBlock(chainDb, block); err != nil {
        return nil, err
    }
    if err := WriteBlockReceipts(chainDb, block.Hash(), block.NumberU64(), nil); err != nil {
        return nil, err
    }
    if err := WriteCanonicalHash(chainDb, block.Hash(), block.NumberU64()); err != nil {
        return nil, err
    }
    if err := WriteHeadBlockHash(chainDb, block.Hash()); err != nil {
        return nil, err
    }
    if err := WriteChainConfig(chainDb, block.Hash(), genesis.ChainConfig); err != nil {
        return nil, err
    }

    return block, nil
}

// GenesisBlockForTesting creates a block in which addr has the given wei balance.
// The state trie of the block is written to db. the passed db needs to contain a state root
func GenesisBlockForTesting(db ethdb.Database, addr common.Address, balance *big.Int) *types.Block {
    statedb, _ := state.New(common.Hash{}, db)
    obj := statedb.GetOrNewStateObject(addr)
    obj.SetBalance(balance)
    root, err := statedb.Commit(false)
    if err != nil {
        panic(fmt.Sprintf("cannot write state: %v", err))
    }
    block := types.NewBlock(&types.Header{
        Difficulty: params.GenesisDifficulty,
        GasLimit:   params.GenesisGasLimit,
        Root:       root,
    }, nil, nil, nil)
    return block
}

type GenesisAccount struct {
    Address common.Address
    Balance *big.Int
}

func WriteGenesisBlockForTesting(db ethdb.Database, accounts ...GenesisAccount) *types.Block {
    accountJson := "{"
    for i, account := range accounts {
        if i != 0 {
            accountJson += ","
        }
        accountJson += fmt.Sprintf(`"0x%x":{"balance":"0x%x"}`, account.Address, account.Balance.Bytes())
    }
    accountJson += "}"

    testGenesis := fmt.Sprintf(`{
    "nonce":"0x%x",
    "gasLimit":"0x%x",
    "difficulty":"0x%x",
    "alloc": %s
}`, types.EncodeNonce(0), params.GenesisGasLimit.Bytes(), params.GenesisDifficulty.Bytes(), accountJson)
    block, _ := WriteGenesisBlock(db, strings.NewReader(testGenesis))
    return block
}

// WriteDefaultGenesisBlock assembles the official Ethereum genesis block and
// writes it - along with all associated state - into a chain database.
func WriteDefaultGenesisBlock(chainDb ethdb.Database) (*types.Block, error) {
    return WriteGenesisBlock(chainDb, strings.NewReader(DefaultGenesisBlock()))
}

// WriteTestNetGenesisBlock assembles the test network genesis block and
// writes it - along with all associated state - into a chain database.
func WriteTestNetGenesisBlock(chainDb ethdb.Database) (*types.Block, error) {
    return WriteGenesisBlock(chainDb, strings.NewReader(DefaultTestnetGenesisBlock()))
}

// DefaultGenesisBlock assembles a JSON string representing the default Ethereum
// genesis block.
func DefaultGenesisBlock() string {
    reader, err := gzip.NewReader(base64.NewDecoder(base64.StdEncoding, strings.NewReader(defaultGenesisBlock)))
    if err != nil {
        panic(fmt.Sprintf("failed to access default genesis: %v", err))
    }
    blob, err := ioutil.ReadAll(reader)
    if err != nil {
        panic(fmt.Sprintf("failed to load default genesis: %v", err))
    }
    return string(blob)
}

// DefaultTestnetGenesisBlock assembles a JSON string representing the default Ethereum
// test network genesis block.
func DefaultTestnetGenesisBlock() string {
    reader := bzip2.NewReader(base64.NewDecoder(base64.StdEncoding, strings.NewReader(defaultTestnetGenesisBlock)))
    blob, err := ioutil.ReadAll(reader)
    if err != nil {
        panic(fmt.Sprintf("failed to load default genesis: %v", err))
    }
    return string(blob)
}

// DevGenesisBlock assembles a JSON string representing a local dev genesis block.
func DevGenesisBlock() string {
    reader := bzip2.NewReader(base64.NewDecoder(base64.StdEncoding, strings.NewReader(defaultDevnetGenesisBlock)))
    blob, err := ioutil.ReadAll(reader)
    if err != nil {
        panic(fmt.Sprintf("failed to load dev genesis: %v", err))
    }
    return string(blob)
}