Make maximum keypool size a config option.

account.go

@@ -548,7 +548,7 @@ func (a *Account) NewAddress() (btcutil.Address, error) {
 	}
 
 	// Get next address from wallet.
-	addr, err := a.NextChainedAddress(&bs)
+	addr, err := a.NextChainedAddress(&bs, cfg.KeypoolSize)
 	if err != nil {
 		a.mtx.Unlock()
 		return nil, err

accountstore.go

@@ -189,7 +189,7 @@ func (store *AccountStore) CreateEncryptedWallet(name, desc string, passphrase [
 	}
 
 	// Create new wallet in memory.
-	wlt, err := wallet.NewWallet(name, desc, passphrase, cfg.Net(), &bs)
+	wlt, err := wallet.NewWallet(name, desc, passphrase, cfg.Net(), &bs, cfg.KeypoolSize)
 	if err != nil {
 		return err
 	}

config.go

@@ -32,6 +32,7 @@ const (
 	defaultConfigFilename = "btcwallet.conf"
 	defaultBtcNet         = btcwire.TestNet3
 	defaultLogLevel       = "info"
+	defaultKeypoolSize    = 100
 )
 
 var (
@@ -58,6 +59,7 @@ type config struct {
 	RPCCert      string   `long:"rpccert" description:"File containing the certificate file"`
 	RPCKey       string   `long:"rpckey" description:"File containing the certificate key"`
 	MainNet      bool     `long:"mainnet" description:"Use the main Bitcoin network (default testnet3)"`
+	KeypoolSize  uint     `short:"k" long:"keypoolsize" description:"Maximum number of addresses in keypool"`
 	Proxy        string   `long:"proxy" description:"Connect via SOCKS5 proxy (eg. 127.0.0.1:9050)"`
 	ProxyUser    string   `long:"proxyuser" description:"Username for proxy server"`
 	ProxyPass    string   `long:"proxypass" default-mask:"-" description:"Password for proxy server"`
@@ -137,11 +139,12 @@ func normalizeAddress(addr, defaultPort string) string {
 func loadConfig() (*config, []string, error) {
 	// Default config.
 	cfg := config{
-		DebugLevel: defaultLogLevel,
-		ConfigFile: defaultConfigFile,
-		DataDir:    defaultDataDir,
-		RPCKey:     defaultRPCKeyFile,
-		RPCCert:    defaultRPCCertFile,
+		DebugLevel:  defaultLogLevel,
+		ConfigFile:  defaultConfigFile,
+		DataDir:     defaultDataDir,
+		RPCKey:      defaultRPCKeyFile,
+		RPCCert:     defaultRPCCertFile,
+		KeypoolSize: defaultKeypoolSize,
 	}
 
 	// A config file in the current directory takes precedence.

createtx.go

@@ -245,7 +245,7 @@ func (a *Account) txToPairs(pairs map[string]int64, minconf int) (*CreatedTx, er
 
 			// Get a new change address if one has not already been found.
 			if changeAddr == nil {
-				changeAddr, err = a.NextChainedAddress(&bs)
+				changeAddr, err = a.NextChainedAddress(&bs, cfg.KeypoolSize)
 				if err != nil {
 					return nil, fmt.Errorf("failed to get next address: %s", err)
 				}

sample-btcwallet.conf

@@ -12,6 +12,9 @@
 ; directory for mainnet and testnet wallets, respectively.
 ; datadir=~/.btcwallet
 
+; Maximum number of addresses to generate for the keypool
+; keypoolsize=100
+
 
 
 ; ------------------------------------------------------------------------------

wallet/wallet.go

@@ -46,9 +46,6 @@ const (
 	// Maximum length in bytes of a comment that can have a size represented
 	// as a uint16.
 	maxCommentLen = (1 << 16) - 1
-
-	// Number of addresses to extend keypool by.
-	nKeypoolIncrement = 100
 )
 
 const (
@@ -455,7 +452,7 @@ type Wallet struct {
 	addrCommentMap map[btcutil.AddressPubKeyHash]comment
 	txCommentMap   map[transactionHashKey]comment
 
-	// These are not serialized.
+	// The rest of the fields in this struct are not serialized.
 	secret struct {
 		sync.Mutex
 		key []byte
@@ -469,7 +466,9 @@ type Wallet struct {
 // desc's binary representation must not exceed 32 and 256 bytes,
 // respectively.  All address private keys are encrypted with passphrase.
 // The wallet is returned unlocked.
-func NewWallet(name, desc string, passphrase []byte, net btcwire.BitcoinNet, createdAt *BlockStamp) (*Wallet, error) {
+func NewWallet(name, desc string, passphrase []byte, net btcwire.BitcoinNet,
+	createdAt *BlockStamp, keypoolSize uint) (*Wallet, error) {
+
 	// Check sizes of inputs.
 	if len([]byte(name)) > 32 {
 		return nil, errors.New("name exceeds 32 byte maximum size")
@@ -546,7 +545,7 @@ func NewWallet(name, desc string, passphrase []byte, net btcwire.BitcoinNet, cre
 	w.chainIdxMap[rootKeyChainIdx] = w.keyGenerator.address(net)
 
 	// Fill keypool.
-	if err := w.extendKeypool(nKeypoolIncrement, aeskey, createdAt); err != nil {
+	if err := w.extendKeypool(keypoolSize, aeskey, createdAt); err != nil {
 		return nil, err
 	}
 
@@ -796,7 +795,9 @@ func (w *Wallet) Version() (string, int) {
 
 // NextChainedAddress attempts to get the next chained address,
 // refilling the keypool if necessary.
-func (w *Wallet) NextChainedAddress(bs *BlockStamp) (*btcutil.AddressPubKeyHash, error) {
+func (w *Wallet) NextChainedAddress(bs *BlockStamp,
+	keypoolSize uint) (*btcutil.AddressPubKeyHash, error) {
+
 	// Attempt to get address hash of next chained address.
 	next160, ok := w.chainIdxMap[w.highestUsed+1]
 	if !ok {
@@ -810,7 +811,7 @@ func (w *Wallet) NextChainedAddress(bs *BlockStamp) (*btcutil.AddressPubKeyHash,
 		copy(aeskey, w.secret.key)
 		w.secret.Unlock()
 
-		err := w.extendKeypool(nKeypoolIncrement, aeskey, bs)
+		err := w.extendKeypool(keypoolSize, aeskey, bs)
 		if err != nil {
 			return nil, err
 		}