path: root/cmd/utils/flags.go

// Copyright 2015 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.

package utils

import (
    "crypto/ecdsa"
    "fmt"
    "io/ioutil"
    "math"
    "math/big"
    "math/rand"
    "os"
    "path/filepath"
    "runtime"
    "strconv"
    "strings"
    "time"

    "github.com/ethereum/ethash"
    "github.com/ethereum/go-ethereum/accounts"
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/core"
    "github.com/ethereum/go-ethereum/core/state"
    "github.com/ethereum/go-ethereum/crypto"
    "github.com/ethereum/go-ethereum/eth"
    "github.com/ethereum/go-ethereum/ethdb"
    "github.com/ethereum/go-ethereum/event"
    "github.com/ethereum/go-ethereum/les"
    "github.com/ethereum/go-ethereum/light"
    "github.com/ethereum/go-ethereum/logger"
    "github.com/ethereum/go-ethereum/logger/glog"
    "github.com/ethereum/go-ethereum/metrics"
    "github.com/ethereum/go-ethereum/node"
    "github.com/ethereum/go-ethereum/p2p/discover"
    "github.com/ethereum/go-ethereum/p2p/nat"
    "github.com/ethereum/go-ethereum/params"
    "github.com/ethereum/go-ethereum/pow"
    "github.com/ethereum/go-ethereum/rpc"
    whisper "github.com/ethereum/go-ethereum/whisper/whisperv2"
    "gopkg.in/urfave/cli.v1"
)

func init() {
    cli.AppHelpTemplate = `{{.Name}} {{if .Flags}}[global options] {{end}}command{{if .Flags}} [command options]{{end}} [arguments...]

VERSION:
   {{.Version}}

COMMANDS:
   {{range .Commands}}{{.Name}}{{with .ShortName}}, {{.}}{{end}}{{ "\t" }}{{.Usage}}
   {{end}}{{if .Flags}}
GLOBAL OPTIONS:
   {{range .Flags}}{{.}}
   {{end}}{{end}}
`

    cli.CommandHelpTemplate = `{{.Name}}{{if .Subcommands}} command{{end}}{{if .Flags}} [command options]{{end}} [arguments...]
{{if .Description}}{{.Description}}
{{end}}{{if .Subcommands}}
SUBCOMMANDS:
    {{range .Subcommands}}{{.Name}}{{with .ShortName}}, {{.}}{{end}}{{ "\t" }}{{.Usage}}
    {{end}}{{end}}{{if .Flags}}
OPTIONS:
    {{range .Flags}}{{.}}
    {{end}}{{end}}
`
}

// NewApp creates an app with sane defaults.
func NewApp(gitCommit, usage string) *cli.App {
    app := cli.NewApp()
    app.Name = filepath.Base(os.Args[0])
    app.Author = ""
    //app.Authors = nil
    app.Email = ""
    app.Version = Version
    if gitCommit != "" {
        app.Version += "-" + gitCommit[:8]
    }
    app.Usage = usage
    return app
}

// These are all the command line flags we support.
// If you add to this list, please remember to include the
// flag in the appropriate command definition.
//
// The flags are defined here so their names and help texts
// are the same for all commands.

var (
    // General settings
    DataDirFlag = DirectoryFlag{
        Name:  "datadir",
        Usage: "Data directory for the databases and keystore",
        Value: DirectoryString{node.DefaultDataDir()},
    }
    KeyStoreDirFlag = DirectoryFlag{
        Name:  "keystore",
        Usage: "Directory for the keystore (default = inside the datadir)",
    }
    NetworkIdFlag = cli.IntFlag{
        Name:  "networkid",
        Usage: "Network identifier (integer, 0=Olympic, 1=Frontier, 2=Morden)",
        Value: eth.NetworkId,
    }
    OlympicFlag = cli.BoolFlag{
        Name:  "olympic",
        Usage: "Olympic network: pre-configured pre-release test network",
    }
    TestNetFlag = cli.BoolFlag{
        Name:  "testnet",
        Usage: "Morden network: pre-configured test network with modified starting nonces (replay protection)",
    }
    DevModeFlag = cli.BoolFlag{
        Name:  "dev",
        Usage: "Developer mode: pre-configured private network with several debugging flags",
    }
    IdentityFlag = cli.StringFlag{
        Name:  "identity",
        Usage: "Custom node name",
    }
    NatspecEnabledFlag = cli.BoolFlag{
        Name:  "natspec",
        Usage: "Enable NatSpec confirmation notice",
    }
    DocRootFlag = DirectoryFlag{
        Name:  "docroot",
        Usage: "Document Root for HTTPClient file scheme",
        Value: DirectoryString{homeDir()},
    }
    FastSyncFlag = cli.BoolFlag{
        Name:  "fast",
        Usage: "Enable fast syncing through state downloads",
    }
    LightModeFlag = cli.BoolFlag{
        Name:  "light",
        Usage: "Enable light client mode",
    }
    LightServFlag = cli.IntFlag{
        Name:  "lightserv",
        Usage: "Maximum percentage of time allowed for serving LES requests (0-90)",
        Value: 0,
    }
    LightPeersFlag = cli.IntFlag{
        Name:  "lightpeers",
        Usage: "Maximum number of LES client peers",
        Value: 20,
    }
    LightKDFFlag = cli.BoolFlag{
        Name:  "lightkdf",
        Usage: "Reduce key-derivation RAM & CPU usage at some expense of KDF strength",
    }
    // Performance tuning settings
    CacheFlag = cli.IntFlag{
        Name:  "cache",
        Usage: "Megabytes of memory allocated to internal caching (min 16MB / database forced)",
        Value: 128,
    }
    TrieCacheGenFlag = cli.IntFlag{
        Name:  "trie-cache-gens",
        Usage: "Number of trie node generations to keep in memory",
        Value: int(state.MaxTrieCacheGen),
    }
    // Fork settings
    SupportDAOFork = cli.BoolFlag{
        Name:  "support-dao-fork",
        Usage: "Updates the chain rules to support the DAO hard-fork",
    }
    OpposeDAOFork = cli.BoolFlag{
        Name:  "oppose-dao-fork",
        Usage: "Updates the chain rules to oppose the DAO hard-fork",
    }
    // Miner settings
    MiningEnabledFlag = cli.BoolFlag{
        Name:  "mine",
        Usage: "Enable mining",
    }
    MinerThreadsFlag = cli.IntFlag{
        Name:  "minerthreads",
        Usage: "Number of CPU threads to use for mining",
        Value: runtime.NumCPU(),
    }
    TargetGasLimitFlag = cli.StringFlag{
        Name:  "targetgaslimit",
        Usage: "Target gas limit sets the artificial target gas floor for the blocks to mine",
        Value: params.GenesisGasLimit.String(),
    }
    AutoDAGFlag = cli.BoolFlag{
        Name:  "autodag",
        Usage: "Enable automatic DAG pregeneration",
    }
    EtherbaseFlag = cli.StringFlag{
        Name:  "etherbase",
        Usage: "Public address for block mining rewards (default = first account created)",
        Value: "0",
    }
    GasPriceFlag = cli.StringFlag{
        Name:  "gasprice",
        Usage: "Minimal gas price to accept for mining a transactions",
        Value: new(big.Int).Mul(big.NewInt(20), common.Shannon).String(),
    }
    ExtraDataFlag = cli.StringFlag{
        Name:  "extradata",
        Usage: "Block extra data set by the miner (default = client version)",
    }
    // Account settings
    UnlockedAccountFlag = cli.StringFlag{
        Name:  "unlock",
        Usage: "Comma separated list of accounts to unlock",
        Value: "",
    }
    PasswordFileFlag = cli.StringFlag{
        Name:  "password",
        Usage: "Password file to use for non-inteactive password input",
        Value: "",
    }

    VMForceJitFlag = cli.BoolFlag{
        Name:  "forcejit",
        Usage: "Force the JIT VM to take precedence",
    }
    VMJitCacheFlag = cli.IntFlag{
        Name:  "jitcache",
        Usage: "Amount of cached JIT VM programs",
        Value: 64,
    }
    VMEnableJitFlag = cli.BoolFlag{
        Name:  "jitvm",
        Usage: "Enable the JIT VM",
    }

    // logging and debug settings
    MetricsEnabledFlag = cli.BoolFlag{
        Name:  metrics.MetricsEnabledFlag,
        Usage: "Enable metrics collection and reporting",
    }
    FakePoWFlag = cli.BoolFlag{
        Name:  "fakepow",
        Usage: "Disables proof-of-work verification",
    }

    // RPC settings
    RPCEnabledFlag = cli.BoolFlag{
        Name:  "rpc",
        Usage: "Enable the HTTP-RPC server",
    }
    RPCListenAddrFlag = cli.StringFlag{
        Name:  "rpcaddr",
        Usage: "HTTP-RPC server listening interface",
        Value: node.DefaultHTTPHost,
    }
    RPCPortFlag = cli.IntFlag{
        Name:  "rpcport",
        Usage: "HTTP-RPC server listening port",
        Value: node.DefaultHTTPPort,
    }
    RPCCORSDomainFlag = cli.StringFlag{
        Name:  "rpccorsdomain",
        Usage: "Comma separated list of domains from which to accept cross origin requests (browser enforced)",
        Value: "",
    }
    RPCApiFlag = cli.StringFlag{
        Name:  "rpcapi",
        Usage: "API's offered over the HTTP-RPC interface",
        Value: rpc.DefaultHTTPApis,
    }
    IPCDisabledFlag = cli.BoolFlag{
        Name:  "ipcdisable",
        Usage: "Disable the IPC-RPC server",
    }
    IPCApiFlag = cli.StringFlag{
        Name:  "ipcapi",
        Usage: "APIs offered over the IPC-RPC interface",
        Value: rpc.DefaultIPCApis,
    }
    IPCPathFlag = DirectoryFlag{
        Name:  "ipcpath",
        Usage: "Filename for IPC socket/pipe within the datadir (explicit paths escape it)",
        Value: DirectoryString{"geth.ipc"},
    }
    WSEnabledFlag = cli.BoolFlag{
        Name:  "ws",
        Usage: "Enable the WS-RPC server",
    }
    WSListenAddrFlag = cli.StringFlag{
        Name:  "wsaddr",
        Usage: "WS-RPC server listening interface",
        Value: node.DefaultWSHost,
    }
    WSPortFlag = cli.IntFlag{
        Name:  "wsport",
        Usage: "WS-RPC server listening port",
        Value: node.DefaultWSPort,
    }
    WSApiFlag = cli.StringFlag{
        Name:  "wsapi",
        Usage: "API's offered over the WS-RPC interface",
        Value: rpc.DefaultHTTPApis,
    }
    WSAllowedOriginsFlag = cli.StringFlag{
        Name:  "wsorigins",
        Usage: "Origins from which to accept websockets requests",
        Value: "",
    }
    ExecFlag = cli.StringFlag{
        Name:  "exec",
        Usage: "Execute JavaScript statement (only in combination with console/attach)",
    }
    PreloadJSFlag = cli.StringFlag{
        Name:  "preload",
        Usage: "Comma separated list of JavaScript files to preload into the console",
    }

    // Network Settings
    MaxPeersFlag = cli.IntFlag{
        Name:  "maxpeers",
        Usage: "Maximum number of network peers (network disabled if set to 0)",
        Value: 25,
    }
    MaxPendingPeersFlag = cli.IntFlag{
        Name:  "maxpendpeers",
        Usage: "Maximum number of pending connection attempts (defaults used if set to 0)",
        Value: 0,
    }
    ListenPortFlag = cli.IntFlag{
        Name:  "port",
        Usage: "Network listening port",
        Value: 30303,
    }
    BootnodesFlag = cli.StringFlag{
        Name:  "bootnodes",
        Usage: "Comma separated enode URLs for P2P discovery bootstrap",
        Value: "",
    }
    NodeKeyFileFlag = cli.StringFlag{
        Name:  "nodekey",
        Usage: "P2P node key file",
    }
    NodeKeyHexFlag = cli.StringFlag{
        Name:  "nodekeyhex",
        Usage: "P2P node key as hex (for testing)",
    }
    NATFlag = cli.StringFlag{
        Name:  "nat",
        Usage: "NAT port mapping mechanism (any|none|upnp|pmp|extip:<IP>)",
        Value: "any",
    }
    NoDiscoverFlag = cli.BoolFlag{
        Name:  "nodiscover",
        Usage: "Disables the peer discovery mechanism (manual peer addition)",
    }
    DiscoveryV5Flag = cli.BoolFlag{
        Name:  "v5disc",
        Usage: "Enables the experimental RLPx V5 (Topic Discovery) mechanism",
    }
    WhisperEnabledFlag = cli.BoolFlag{
        Name:  "shh",
        Usage: "Enable Whisper",
    }
    // ATM the url is left to the user and deployment to
    JSpathFlag = cli.StringFlag{
        Name:  "jspath",
        Usage: "JavaScript root path for `loadScript` and document root for `admin.httpGet`",
        Value: ".",
    }
    SolcPathFlag = cli.StringFlag{
        Name:  "solc",
        Usage: "Solidity compiler command to be used",
        Value: "solc",
    }

    // Gas price oracle settings
    GpoMinGasPriceFlag = cli.StringFlag{
        Name:  "gpomin",
        Usage: "Minimum suggested gas price",
        Value: new(big.Int).Mul(big.NewInt(20), common.Shannon).String(),
    }
    GpoMaxGasPriceFlag = cli.StringFlag{
        Name:  "gpomax",
        Usage: "Maximum suggested gas price",
        Value: new(big.Int).Mul(big.NewInt(500), common.Shannon).String(),
    }
    GpoFullBlockRatioFlag = cli.IntFlag{
        Name:  "gpofull",
        Usage: "Full block threshold for gas price calculation (%)",
        Value: 80,
    }
    GpobaseStepDownFlag = cli.IntFlag{
        Name:  "gpobasedown",
        Usage: "Suggested gas price base step down ratio (1/1000)",
        Value: 10,
    }
    GpobaseStepUpFlag = cli.IntFlag{
        Name:  "gpobaseup",
        Usage: "Suggested gas price base step up ratio (1/1000)",
        Value: 100,
    }
    GpobaseCorrectionFactorFlag = cli.IntFlag{
        Name:  "gpobasecf",
        Usage: "Suggested gas price base correction factor (%)",
        Value: 110,
    }
)

// MakeDataDir retrieves the currently requested data directory, terminating
// if none (or the empty string) is specified. If the node is starting a testnet,
// the a subdirectory of the specified datadir will be used.
func MakeDataDir(ctx *cli.Context) string {
    if path := ctx.GlobalString(DataDirFlag.Name); path != "" {
        // TODO: choose a different location outside of the regular datadir.
        if ctx.GlobalBool(TestNetFlag.Name) {
            return filepath.Join(path, "testnet")
        }
        return path
    }
    Fatalf("Cannot determine default data directory, please set manually (--datadir)")
    return ""
}

// MakeIPCPath creates an IPC path configuration from the set command line flags,
// returning an empty string if IPC was explicitly disabled, or the set path.
func MakeIPCPath(ctx *cli.Context) string {
    if ctx.GlobalBool(IPCDisabledFlag.Name) {
        return ""
    }
    return ctx.GlobalString(IPCPathFlag.Name)
}

// MakeNodeKey creates a node key from set command line flags, either loading it
// from a file or as a specified hex value. If neither flags were provided, this
// method returns nil and an emphemeral key is to be generated.
func MakeNodeKey(ctx *cli.Context) *ecdsa.PrivateKey {
    var (
        hex  = ctx.GlobalString(NodeKeyHexFlag.Name)
        file = ctx.GlobalString(NodeKeyFileFlag.Name)

        key *ecdsa.PrivateKey
        err error
    )
    switch {
    case file != "" && hex != "":
        Fatalf("Options %q and %q are mutually exclusive", NodeKeyFileFlag.Name, NodeKeyHexFlag.Name)

    case file != "":
        if key, err = crypto.LoadECDSA(file); err != nil {
            Fatalf("Option %q: %v", NodeKeyFileFlag.Name, err)
        }

    case hex != "":
        if key, err = crypto.HexToECDSA(hex); err != nil {
            Fatalf("Option %q: %v", NodeKeyHexFlag.Name, err)
        }
    }
    return key
}

// makeNodeUserIdent creates the user identifier from CLI flags.
func makeNodeUserIdent(ctx *cli.Context) string {
    var comps []string
    if identity := ctx.GlobalString(IdentityFlag.Name); len(identity) > 0 {
        comps = append(comps, identity)
    }
    if ctx.GlobalBool(VMEnableJitFlag.Name) {
        comps = append(comps, "JIT")
    }
    return strings.Join(comps, "/")
}

// MakeBootstrapNodes creates a list of bootstrap nodes from the command line
// flags, reverting to pre-configured ones if none have been specified.
func MakeBootstrapNodes(ctx *cli.Context) []*discover.Node {
    // Return pre-configured nodes if none were manually requested
    if !ctx.GlobalIsSet(BootnodesFlag.Name) {
        if ctx.GlobalBool(TestNetFlag.Name) {
            return TestNetBootNodes
        }
        return FrontierBootNodes
    }
    // Otherwise parse and use the CLI bootstrap nodes
    bootnodes := []*discover.Node{}

    for _, url := range strings.Split(ctx.GlobalString(BootnodesFlag.Name), ",") {
        node, err := discover.ParseNode(url)
        if err != nil {
            glog.V(logger.Error).Infof("Bootstrap URL %s: %v\n", url, err)
            continue
        }
        bootnodes = append(bootnodes, node)
    }
    return bootnodes
}

// MakeListenAddress creates a TCP listening address string from set command
// line flags.
func MakeListenAddress(ctx *cli.Context) string {
    return fmt.Sprintf(":%d", ctx.GlobalInt(ListenPortFlag.Name))
}

func MakeListenAddressV5(ctx *cli.Context) string {
    return fmt.Sprintf(":%d", ctx.GlobalInt(ListenPortFlag.Name)+1)
}

// MakeNAT creates a port mapper from set command line flags.
func MakeNAT(ctx *cli.Context) nat.Interface {
    natif, err := nat.Parse(ctx.GlobalString(NATFlag.Name))
    if err != nil {
        Fatalf("Option %s: %v", NATFlag.Name, err)
    }
    return natif
}

// MakeRPCModules splits input separated by a comma and trims excessive white
// space from the substrings.
func MakeRPCModules(input string) []string {
    result := strings.Split(input, ",")
    for i, r := range result {
        result[i] = strings.TrimSpace(r)
    }
    return result
}

// MakeHTTPRpcHost creates the HTTP RPC listener interface string from the set
// command line flags, returning empty if the HTTP endpoint is disabled.
func MakeHTTPRpcHost(ctx *cli.Context) string {
    if !ctx.GlobalBool(RPCEnabledFlag.Name) {
        return ""
    }
    return ctx.GlobalString(RPCListenAddrFlag.Name)
}

// MakeWSRpcHost creates the WebSocket RPC listener interface string from the set
// command line flags, returning empty if the HTTP endpoint is disabled.
func MakeWSRpcHost(ctx *cli.Context) string {
    if !ctx.GlobalBool(WSEnabledFlag.Name) {
        return ""
    }
    return ctx.GlobalString(WSListenAddrFlag.Name)
}

// MakeDatabaseHandles raises out the number of allowed file handles per process
// for Geth and returns half of the allowance to assign to the database.
func MakeDatabaseHandles() int {
    if err := raiseFdLimit(2048); err != nil {
        Fatalf("Failed to raise file descriptor allowance: %v", err)
    }
    limit, err := getFdLimit()
    if err != nil {
        Fatalf("Failed to retrieve file descriptor allowance: %v", err)
    }
    if limit > 2048 { // cap database file descriptors even if more is available
        limit = 2048
    }
    return limit / 2 // Leave half for networking and other stuff
}

// MakeAddress converts an account specified directly as a hex encoded string or
// a key index in the key store to an internal account representation.
func MakeAddress(accman *accounts.Manager, account string) (accounts.Account, error) {
    // If the specified account is a valid address, return it
    if common.IsHexAddress(account) {
        return accounts.Account{Address: common.HexToAddress(account)}, nil
    }
    // Otherwise try to interpret the account as a keystore index
    index, err := strconv.Atoi(account)
    if err != nil {
        return accounts.Account{}, fmt.Errorf("invalid account address or index %q", account)
    }
    return accman.AccountByIndex(index)
}

// MakeEtherbase retrieves the etherbase either from the directly specified
// command line flags or from the keystore if CLI indexed.
func MakeEtherbase(accman *accounts.Manager, ctx *cli.Context) common.Address {
    accounts := accman.Accounts()
    if !ctx.GlobalIsSet(EtherbaseFlag.Name) && len(accounts) == 0 {
        glog.V(logger.Error).Infoln("WARNING: No etherbase set and no accounts found as default")
        return common.Address{}
    }
    etherbase := ctx.GlobalString(EtherbaseFlag.Name)
    if etherbase == "" {
        return common.Address{}
    }
    // If the specified etherbase is a valid address, return it
    account, err := MakeAddress(accman, etherbase)
    if err != nil {
        Fatalf("Option %q: %v", EtherbaseFlag.Name, err)
    }
    return account.Address
}

// MakeMinerExtra resolves extradata for the miner from the set command line flags
// or returns a default one composed on the client, runtime and OS metadata.
func MakeMinerExtra(extra []byte, ctx *cli.Context) []byte {
    if ctx.GlobalIsSet(ExtraDataFlag.Name) {
        return []byte(ctx.GlobalString(ExtraDataFlag.Name))
    }
    return extra
}

// MakePasswordList reads password lines from the file specified by --password.
func MakePasswordList(ctx *cli.Context) []string {
    path := ctx.GlobalString(PasswordFileFlag.Name)
    if path == "" {
        return nil
    }
    text, err := ioutil.ReadFile(path)
    if err != nil {
        Fatalf("Failed to read password file: %v", err)
    }
    lines := strings.Split(string(text), "\n")
    // Sanitise DOS line endings.
    for i := range lines {
        lines[i] = strings.TrimRight(lines[i], "\r")
    }
    return lines
}

// MakeNode configures a node with no services from command line flags.
func MakeNode(ctx *cli.Context, name, gitCommit string) *node.Node {
    vsn := Version
    if gitCommit != "" {
        vsn += "-" + gitCommit[:8]
    }

    config := &node.Config{
        DataDir:           MakeDataDir(ctx),
        KeyStoreDir:       ctx.GlobalString(KeyStoreDirFlag.Name),
        UseLightweightKDF: ctx.GlobalBool(LightKDFFlag.Name),
        PrivateKey:        MakeNodeKey(ctx),
        Name:              name,
        Version:           vsn,
        UserIdent:         makeNodeUserIdent(ctx),
        NoDiscovery:       ctx.GlobalBool(NoDiscoverFlag.Name) || ctx.GlobalBool(LightModeFlag.Name),
        DiscoveryV5:       ctx.GlobalBool(DiscoveryV5Flag.Name) || ctx.GlobalBool(LightModeFlag.Name) || ctx.GlobalInt(LightServFlag.Name) > 0,
        BootstrapNodes:    MakeBootstrapNodes(ctx),
        ListenAddr:        MakeListenAddress(ctx),
        ListenAddrV5:      MakeListenAddressV5(ctx),
        NAT:               MakeNAT(ctx),
        MaxPeers:          ctx.GlobalInt(MaxPeersFlag.Name),
        MaxPendingPeers:   ctx.GlobalInt(MaxPendingPeersFlag.Name),
        IPCPath:           MakeIPCPath(ctx),
        HTTPHost:          MakeHTTPRpcHost(ctx),
        HTTPPort:          ctx.GlobalInt(RPCPortFlag.Name),
        HTTPCors:          ctx.GlobalString(RPCCORSDomainFlag.Name),
        HTTPModules:       MakeRPCModules(ctx.GlobalString(RPCApiFlag.Name)),
        WSHost:            MakeWSRpcHost(ctx),
        WSPort:            ctx.GlobalInt(WSPortFlag.Name),
        WSOrigins:         ctx.GlobalString(WSAllowedOriginsFlag.Name),
        WSModules:         MakeRPCModules(ctx.GlobalString(WSApiFlag.Name)),
    }
    if ctx.GlobalBool(DevModeFlag.Name) {
        if !ctx.GlobalIsSet(DataDirFlag.Name) {
            config.DataDir = filepath.Join(os.TempDir(), "/ethereum_dev_mode")
        }
        // --dev mode does not need p2p networking.
        config.MaxPeers = 0
        config.ListenAddr = ":0"
    }
    stack, err := node.New(config)
    if err != nil {
        Fatalf("Failed to create the protocol stack: %v", err)
    }
    return stack
}

// RegisterEthService configures eth.Ethereum from command line flags and adds it to the
// given node.
func RegisterEthService(ctx *cli.Context, stack *node.Node, extra []byte) {
    // Avoid conflicting network flags
    networks, netFlags := 0, []cli.BoolFlag{DevModeFlag, TestNetFlag, OlympicFlag}
    for _, flag := range netFlags {
        if ctx.GlobalBool(flag.Name) {
            networks++
        }
    }
    if networks > 1 {
        Fatalf("The %v flags are mutually exclusive", netFlags)
    }

    // initialise new random number generator
    rand := rand.New(rand.NewSource(time.Now().UnixNano()))
    // get enabled jit flag
    jitEnabled := ctx.GlobalBool(VMEnableJitFlag.Name)
    // if the jit is not enabled enable it for 10 pct of the people
    if !jitEnabled && rand.Float64() < 0.1 {
        jitEnabled = true
        glog.V(logger.Info).Infoln("You're one of the lucky few that will try out the JIT VM (random). If you get a consensus failure please be so kind to report this incident with the block hash that failed. You can switch to the regular VM by setting --jitvm=false")
    }

    ethConf := &eth.Config{
        Etherbase:               MakeEtherbase(stack.AccountManager(), ctx),
        ChainConfig:             MakeChainConfig(ctx, stack),
        FastSync:                ctx.GlobalBool(FastSyncFlag.Name),
        LightMode:               ctx.GlobalBool(LightModeFlag.Name),
        LightServ:               ctx.GlobalInt(LightServFlag.Name),
        LightPeers:              ctx.GlobalInt(LightPeersFlag.Name),
        MaxPeers:                ctx.GlobalInt(MaxPeersFlag.Name),
        DatabaseCache:           ctx.GlobalInt(CacheFlag.Name),
        DatabaseHandles:         MakeDatabaseHandles(),
        NetworkId:               ctx.GlobalInt(NetworkIdFlag.Name),
        MinerThreads:            ctx.GlobalInt(MinerThreadsFlag.Name),
        ExtraData:               MakeMinerExtra(extra, ctx),
        NatSpec:                 ctx.GlobalBool(NatspecEnabledFlag.Name),
        DocRoot:                 ctx.GlobalString(DocRootFlag.Name),
        EnableJit:               jitEnabled,
        ForceJit:                ctx.GlobalBool(VMForceJitFlag.Name),
        GasPrice:                common.String2Big(ctx.GlobalString(GasPriceFlag.Name)),
        GpoMinGasPrice:          common.String2Big(ctx.GlobalString(GpoMinGasPriceFlag.Name)),
        GpoMaxGasPrice:          common.String2Big(ctx.GlobalString(GpoMaxGasPriceFlag.Name)),
        GpoFullBlockRatio:       ctx.GlobalInt(GpoFullBlockRatioFlag.Name),
        GpobaseStepDown:         ctx.GlobalInt(GpobaseStepDownFlag.Name),
        GpobaseStepUp:           ctx.GlobalInt(GpobaseStepUpFlag.Name),
        GpobaseCorrectionFactor: ctx.GlobalInt(GpobaseCorrectionFactorFlag.Name),
        SolcPath:                ctx.GlobalString(SolcPathFlag.Name),
        AutoDAG:                 ctx.GlobalBool(AutoDAGFlag.Name) || ctx.GlobalBool(MiningEnabledFlag.Name),
    }

    // Override any default configs in dev mode or the test net
    switch {
    case ctx.GlobalBool(OlympicFlag.Name):
        if !ctx.GlobalIsSet(NetworkIdFlag.Name) {
            ethConf.NetworkId = 1
        }
        ethConf.Genesis = core.OlympicGenesisBlock()

    case ctx.GlobalBool(TestNetFlag.Name):
        if !ctx.GlobalIsSet(NetworkIdFlag.Name) {
            ethConf.NetworkId = 2
        }
        ethConf.Genesis = core.TestNetGenesisBlock()
        state.StartingNonce = 1048576 // (2**20)
        light.StartingNonce = 1048576 // (2**20)

    case ctx.GlobalBool(DevModeFlag.Name):
        ethConf.Genesis = core.OlympicGenesisBlock()
        if !ctx.GlobalIsSet(GasPriceFlag.Name) {
            ethConf.GasPrice = new(big.Int)
        }
        ethConf.PowTest = true
    }
    // Override any global options pertaining to the Ethereum protocol
    if gen := ctx.GlobalInt(TrieCacheGenFlag.Name); gen > 0 {
        state.MaxTrieCacheGen = uint16(gen)
    }

    if ethConf.LightMode {
        if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
            return les.New(ctx, ethConf)
        }); err != nil {
            Fatalf("Failed to register the Ethereum light node service: %v", err)
        }
    } else {
        if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
            fullNode, err := eth.New(ctx, ethConf)
            if fullNode != nil && ethConf.LightServ > 0 {
                ls, _ := les.NewLesServer(fullNode, ethConf)
                fullNode.AddLesServer(ls)
            }
            return fullNode, err
        }); err != nil {
            Fatalf("Failed to register the Ethereum full node service: %v", err)
        }
    }
}

// RegisterShhService configures whisper and adds it to the given node.
func RegisterShhService(stack *node.Node) {
    if err := stack.Register(func(*node.ServiceContext) (node.Service, error) { return whisper.New(), nil }); err != nil {
        Fatalf("Failed to register the Whisper service: %v", err)
    }
}

// SetupNetwork configures the system for either the main net or some test network.
func SetupNetwork(ctx *cli.Context) {
    switch {
    case ctx.GlobalBool(OlympicFlag.Name):
        params.DurationLimit = big.NewInt(8)
        params.GenesisGasLimit = big.NewInt(3141592)
        params.MinGasLimit = big.NewInt(125000)
        params.MaximumExtraDataSize = big.NewInt(1024)
        NetworkIdFlag.Value = 0
        core.BlockReward = big.NewInt(1.5e+18)
        core.ExpDiffPeriod = big.NewInt(math.MaxInt64)
    }
    params.TargetGasLimit = common.String2Big(ctx.GlobalString(TargetGasLimitFlag.Name))
}

// MakeChainConfig reads the chain configuration from the database in ctx.Datadir.
func MakeChainConfig(ctx *cli.Context, stack *node.Node) *params.ChainConfig {
    db := MakeChainDatabase(ctx, stack)
    defer db.Close()

    return MakeChainConfigFromDb(ctx, db)
}

// MakeChainConfigFromDb reads the chain configuration from the given database.
func MakeChainConfigFromDb(ctx *cli.Context, db ethdb.Database) *params.ChainConfig {
    // If the chain is already initialized, use any existing chain configs
    config := new(params.ChainConfig)

    genesis := core.GetBlock(db, core.GetCanonicalHash(db, 0), 0)
    if genesis != nil {
        storedConfig, err := core.GetChainConfig(db, genesis.Hash())
        switch err {
        case nil:
            config = storedConfig
        case core.ChainConfigNotFoundErr:
            // No configs found, use empty, will populate below
        default:
            Fatalf("Could not make chain configuration: %v", err)
        }
    }
    // Check whether we are allowed to set default config params or not:
    //  - If no genesis is set, we're running either mainnet or testnet (private nets use `geth init`)
    //  - If a genesis is already set, ensure we have a configuration for it (mainnet or testnet)
    defaults := genesis == nil ||
        (genesis.Hash() == params.MainNetGenesisHash && !ctx.GlobalBool(TestNetFlag.Name)) ||
        (genesis.Hash() == params.TestNetGenesisHash && ctx.GlobalBool(TestNetFlag.Name))

    // Set any missing chainConfig fields due to them being unset or system upgrade
    if defaults {
        if config.HomesteadBlock == nil {
            if ctx.GlobalBool(TestNetFlag.Name) {
                config.HomesteadBlock = params.TestNetHomesteadBlock
            } else {
                config.HomesteadBlock = params.MainNetHomesteadBlock
            }
        }
        if config.DAOForkBlock == nil {
            if ctx.GlobalBool(TestNetFlag.Name) {
                config.DAOForkBlock = params.TestNetDAOForkBlock
            } else {
                config.DAOForkBlock = params.MainNetDAOForkBlock
            }
            config.DAOForkSupport = true
        }
        config.DAOForkSupport = true
    }
    if config.EIP150Block == nil {
        if ctx.GlobalBool(TestNetFlag.Name) {
            config.EIP150Block = params.TestNetHomesteadGasRepriceBlock
        } else {
            config.EIP150Block = params.MainNetHomesteadGasRepriceBlock
        }
    }
    if config.EIP150Hash == (common.Hash{}) {
        if ctx.GlobalBool(TestNetFlag.Name) {
            config.EIP150Hash = params.TestNetHomesteadGasRepriceHash
        } else {
            config.EIP150Hash = params.MainNetHomesteadGasRepriceHash
        }
    }
    // Force override any existing configs if explicitly requested
    switch {
    case ctx.GlobalBool(SupportDAOFork.Name):
        config.DAOForkSupport = true
    case ctx.GlobalBool(OpposeDAOFork.Name):
        config.DAOForkSupport = false
    }
    return config
}

func ChainDbName(ctx *cli.Context) string {
    if ctx.GlobalBool(LightModeFlag.Name) {
        return "lightchaindata"
    } else {
        return "chaindata"
    }
}

// MakeChainDatabase open an LevelDB using the flags passed to the client and will hard crash if it fails.
func MakeChainDatabase(ctx *cli.Context, stack *node.Node) ethdb.Database {
    var (
        cache   = ctx.GlobalInt(CacheFlag.Name)
        handles = MakeDatabaseHandles()
        name    = ChainDbName(ctx)
    )

    chainDb, err := stack.OpenDatabase(name, cache, handles)
    if err != nil {
        Fatalf("Could not open database: %v", err)
    }
    return chainDb
}

// MakeChain creates a chain manager from set command line flags.
func MakeChain(ctx *cli.Context, stack *node.Node) (chain *core.BlockChain, chainDb ethdb.Database) {
    var err error
    chainDb = MakeChainDatabase(ctx, stack)

    if ctx.GlobalBool(OlympicFlag.Name) {
        _, err := core.WriteTestNetGenesisBlock(chainDb)
        if err != nil {
            glog.Fatalln(err)
        }
    }
    chainConfig := MakeChainConfigFromDb(ctx, chainDb)

    pow := pow.PoW(core.FakePow{})
    if !ctx.GlobalBool(FakePoWFlag.Name) {
        pow = ethash.New()
    }
    chain, err = core.NewBlockChain(chainDb, chainConfig, pow, new(event.TypeMux))
    if err != nil {
        Fatalf("Could not start chainmanager: %v", err)
    }
    return chain, chainDb
}

// MakeConsolePreloads retrieves the absolute paths for the console JavaScript
// scripts to preload before starting.
func MakeConsolePreloads(ctx *cli.Context) []string {
    // Skip preloading if there's nothing to preload
    if ctx.GlobalString(PreloadJSFlag.Name) == "" {
        return nil
    }
    // Otherwise resolve absolute paths and return them
    preloads := []string{}

    assets := ctx.GlobalString(JSpathFlag.Name)
    for _, file := range strings.Split(ctx.GlobalString(PreloadJSFlag.Name), ",") {
        preloads = append(preloads, common.AbsolutePath(assets, strings.TrimSpace(file)))
    }
    return preloads
}