X-Git-Url: https://git.r.bdr.sh/rbdr/mobius/blobdiff_plain/aebc4d3647b9823ae8cbb57b21b1af83bfd011fb..c8bfd6061f5079f6c6c0155a2de1e8cd32d8a39a:/hotline/client.go?ds=sidebyside

diff --git a/hotline/client.go b/hotline/client.go
index 4ca42f3..f3e83c8 100644
--- a/hotline/client.go
+++ b/hotline/client.go
@@ -1,6 +1,7 @@
 package hotline
 
 import (
+	"bufio"
 	"bytes"
 	"embed"
 	"encoding/binary"
@@ -10,7 +11,7 @@ import (
 	"github.com/rivo/tview"
 	"github.com/stretchr/testify/mock"
 	"go.uber.org/zap"
-	"gopkg.in/yaml.v2"
+	"gopkg.in/yaml.v3"
 	"math/big"
 	"math/rand"
 	"net"
@@ -35,10 +36,11 @@ type Bookmark struct {
 }
 
 type ClientPrefs struct {
-	Username  string     `yaml:"Username"`
-	IconID    int        `yaml:"IconID"`
-	Bookmarks []Bookmark `yaml:"Bookmarks"`
-	Tracker   string     `yaml:"Tracker"`
+	Username   string     `yaml:"Username"`
+	IconID     int        `yaml:"IconID"`
+	Bookmarks  []Bookmark `yaml:"Bookmarks"`
+	Tracker    string     `yaml:"Tracker"`
+	EnableBell bool       `yaml:"EnableBell"`
 }
 
 func (cp *ClientPrefs) IconBytes() []byte {
@@ -61,7 +63,6 @@ func readConfig(cfgPath string) (*ClientPrefs, error) {
 
 	prefs := ClientPrefs{}
 	decoder := yaml.NewDecoder(fh)
-	decoder.SetStrict(true)
 	if err := decoder.Decode(&prefs); err != nil {
 		return nil, err
 	}
@@ -72,11 +73,6 @@ type Client struct {
 	cfgPath     string
 	DebugBuf    *DebugBuffer
 	Connection  net.Conn
-	Login       *[]byte
-	Password    *[]byte
-	Flags       *[]byte
-	ID          *[]byte
-	Version     []byte
 	UserAccess  []byte
 	filePath    []string
 	UserList    []User
@@ -84,16 +80,33 @@ type Client struct {
 	activeTasks map[uint32]*Transaction
 	serverName  string
 
-	pref *ClientPrefs
+	Pref *ClientPrefs
 
-	Handlers map[uint16]clientTHandler
+	Handlers map[uint16]ClientHandler
 
 	UI *UI
 
 	Inbox chan *Transaction
 }
 
-func NewClient(cfgPath string, logger *zap.SugaredLogger) *Client {
+type ClientHandler func(*Client, *Transaction) ([]Transaction, error)
+
+func (c *Client) HandleFunc(transactionID uint16, handler ClientHandler) {
+	c.Handlers[transactionID] = handler
+}
+
+func NewClient(username string, logger *zap.SugaredLogger) *Client {
+	c := &Client{
+		Logger:      logger,
+		activeTasks: make(map[uint32]*Transaction),
+		Handlers:    make(map[uint16]ClientHandler),
+	}
+	c.Pref = &ClientPrefs{Username: username}
+
+	return c
+}
+
+func NewUIClient(cfgPath string, logger *zap.SugaredLogger) *Client {
 	c := &Client{
 		cfgPath:     cfgPath,
 		Logger:      logger,
@@ -104,10 +117,9 @@ func NewClient(cfgPath string, logger *zap.SugaredLogger) *Client {
 
 	prefs, err := readConfig(cfgPath)
 	if err != nil {
-		fmt.Printf("unable to read config file %s", cfgPath)
-		os.Exit(1)
+		logger.Fatal(fmt.Sprintf("unable to read config file %s\n", cfgPath))
 	}
-	c.pref = prefs
+	c.Pref = prefs
 
 	return c
 }
@@ -121,7 +133,7 @@ func (db *DebugBuffer) Write(p []byte) (int, error) {
 	return db.TextView.Write(p)
 }
 
-// Sync is a noop function that exists to satisfy the zapcore.WriteSyncer interface
+// Sync is a noop function that dataFile to satisfy the zapcore.WriteSyncer interface
 func (db *DebugBuffer) Sync() error {
 	return nil
 }
@@ -135,16 +147,16 @@ func randomBanner() string {
 	return fmt.Sprintf("\n\n\nWelcome to...\n\n[red::b]%s[-:-:-]\n\n", file)
 }
 
-type clientTransaction struct {
+type ClientTransaction struct {
 	Name    string
 	Handler func(*Client, *Transaction) ([]Transaction, error)
 }
 
-func (ch clientTransaction) Handle(cc *Client, t *Transaction) ([]Transaction, error) {
+func (ch ClientTransaction) Handle(cc *Client, t *Transaction) ([]Transaction, error) {
 	return ch.Handler(cc, t)
 }
 
-type clientTHandler interface {
+type ClientTHandler interface {
 	Handle(*Client, *Transaction) ([]Transaction, error)
 }
 
@@ -157,62 +169,28 @@ func (mh *mockClientHandler) Handle(cc *Client, t *Transaction) ([]Transaction,
 	return args.Get(0).([]Transaction), args.Error(1)
 }
 
-var clientHandlers = map[uint16]clientTHandler{
-	// Server initiated
-	tranChatMsg: clientTransaction{
-		Name:    "tranChatMsg",
-		Handler: handleClientChatMsg,
-	},
-	tranLogin: clientTransaction{
-		Name:    "tranLogin",
-		Handler: handleClientTranLogin,
-	},
-	tranShowAgreement: clientTransaction{
-		Name:    "tranShowAgreement",
-		Handler: handleClientTranShowAgreement,
-	},
-	tranUserAccess: clientTransaction{
-		Name:    "tranUserAccess",
-		Handler: handleClientTranUserAccess,
-	},
-	tranGetUserNameList: clientTransaction{
-		Name:    "tranGetUserNameList",
-		Handler: handleClientGetUserNameList,
-	},
-	tranNotifyChangeUser: clientTransaction{
-		Name:    "tranNotifyChangeUser",
-		Handler: handleNotifyChangeUser,
-	},
-	tranNotifyDeleteUser: clientTransaction{
-		Name:    "tranNotifyDeleteUser",
-		Handler: handleNotifyDeleteUser,
-	},
-	tranGetMsgs: clientTransaction{
-		Name:    "tranNotifyDeleteUser",
-		Handler: handleGetMsgs,
-	},
-	tranGetFileNameList: clientTransaction{
-		Name:    "tranGetFileNameList",
-		Handler: handleGetFileNameList,
-	},
-	tranServerMsg: clientTransaction{
-		Name:    "tranServerMsg",
-		Handler: handleTranServerMsg,
-	},
-	tranKeepAlive: clientTransaction{
-		Name: "tranKeepAlive",
-		Handler: func(client *Client, transaction *Transaction) (t []Transaction, err error) {
-			return t, err
-		},
+var clientHandlers = map[uint16]ClientHandler{
+	TranChatMsg:          handleClientChatMsg,
+	TranLogin:            handleClientTranLogin,
+	TranShowAgreement:    handleClientTranShowAgreement,
+	TranUserAccess:       handleClientTranUserAccess,
+	TranGetUserNameList:  handleClientGetUserNameList,
+	TranNotifyChangeUser: handleNotifyChangeUser,
+	TranNotifyDeleteUser: handleNotifyDeleteUser,
+	TranGetMsgs:          handleGetMsgs,
+	TranGetFileNameList:  handleGetFileNameList,
+	TranServerMsg:        handleTranServerMsg,
+	TranKeepAlive: func(client *Client, transaction *Transaction) (t []Transaction, err error) {
+		return t, err
 	},
 }
 
 func handleTranServerMsg(c *Client, t *Transaction) (res []Transaction, err error) {
 	time := time.Now().Format(time.RFC850)
 
-	msg := strings.ReplaceAll(string(t.GetField(fieldData).Data), "\r", "\n")
+	msg := strings.ReplaceAll(string(t.GetField(FieldData).Data), "\r", "\n")
 	msg += "\n\nAt " + time
-	title := fmt.Sprintf("| Private Message From: 	%s |", t.GetField(fieldUserName).Data)
+	title := fmt.Sprintf("| Private Message From: 	%s |", t.GetField(FieldUserName).Data)
 
 	msgBox := tview.NewTextView().SetScrollable(true)
 	msgBox.SetText(msg).SetBackgroundColor(tcell.ColorDarkSlateBlue)
@@ -239,7 +217,41 @@ func handleTranServerMsg(c *Client, t *Transaction) (res []Transaction, err erro
 	return res, err
 }
 
+func (c *Client) showErrMsg(msg string) {
+	time := time.Now().Format(time.RFC850)
+
+	title := "| Error |"
+
+	msgBox := tview.NewTextView().SetScrollable(true)
+	msgBox.SetText(msg).SetBackgroundColor(tcell.ColorDarkRed)
+	msgBox.SetTitle(title).SetBorder(true)
+	msgBox.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
+		switch event.Key() {
+		case tcell.KeyEscape:
+			c.UI.Pages.RemovePage("serverMsgModal" + time)
+		}
+		return event
+	})
+
+	centeredFlex := tview.NewFlex().
+		AddItem(nil, 0, 1, false).
+		AddItem(tview.NewFlex().SetDirection(tview.FlexRow).
+			AddItem(nil, 0, 1, false).
+			AddItem(msgBox, 0, 2, true).
+			AddItem(nil, 0, 1, false), 0, 2, true).
+		AddItem(nil, 0, 1, false)
+
+	c.UI.Pages.AddPage("serverMsgModal"+time, centeredFlex, true, true)
+	c.UI.App.Draw() // TODO: errModal doesn't render without this.  wtf?
+}
+
 func handleGetFileNameList(c *Client, t *Transaction) (res []Transaction, err error) {
+	if t.IsError() {
+		c.showErrMsg(string(t.GetField(FieldError).Data))
+		c.Logger.Infof("Error: %s", t.GetField(FieldError).Data)
+		return res, err
+	}
+
 	fTree := tview.NewTreeView().SetTopLevel(1)
 	root := tview.NewTreeNode("Root")
 	fTree.SetRoot(root).SetCurrentNode(root)
@@ -254,9 +266,9 @@ func handleGetFileNameList(c *Client, t *Transaction) (res []Transaction, err er
 
 			if selectedNode.GetText() == "<- Back" {
 				c.filePath = c.filePath[:len(c.filePath)-1]
-				f := NewField(fieldFilePath, EncodeFilePath(strings.Join(c.filePath, "/")))
+				f := NewField(FieldFilePath, EncodeFilePath(strings.Join(c.filePath, "/")))
 
-				if err := c.UI.HLClient.Send(*NewTransaction(tranGetFileNameList, nil, f)); err != nil {
+				if err := c.UI.HLClient.Send(*NewTransaction(TranGetFileNameList, nil, f)); err != nil {
 					c.UI.HLClient.Logger.Errorw("err", "err", err)
 				}
 				return event
@@ -268,9 +280,9 @@ func handleGetFileNameList(c *Client, t *Transaction) (res []Transaction, err er
 				c.Logger.Infow("get new directory listing", "name", string(entry.name))
 
 				c.filePath = append(c.filePath, string(entry.name))
-				f := NewField(fieldFilePath, EncodeFilePath(strings.Join(c.filePath, "/")))
+				f := NewField(FieldFilePath, EncodeFilePath(strings.Join(c.filePath, "/")))
 
-				if err := c.UI.HLClient.Send(*NewTransaction(tranGetFileNameList, nil, f)); err != nil {
+				if err := c.UI.HLClient.Send(*NewTransaction(TranGetFileNameList, nil, f)); err != nil {
 					c.UI.HLClient.Logger.Errorw("err", "err", err)
 				}
 			} else {
@@ -305,7 +317,6 @@ func handleGetFileNameList(c *Client, t *Transaction) (res []Transaction, err er
 			node.SetReference(&fn)
 			root.AddChild(node)
 		}
-
 	}
 
 	centerFlex := tview.NewFlex().
@@ -324,7 +335,7 @@ func handleGetFileNameList(c *Client, t *Transaction) (res []Transaction, err er
 }
 
 func handleGetMsgs(c *Client, t *Transaction) (res []Transaction, err error) {
-	newsText := string(t.GetField(fieldData).Data)
+	newsText := string(t.GetField(FieldData).Data)
 	newsText = strings.ReplaceAll(newsText, "\r", "\n")
 
 	newsTextView := tview.NewTextView().
@@ -345,10 +356,10 @@ func handleGetMsgs(c *Client, t *Transaction) (res []Transaction, err error) {
 
 func handleNotifyChangeUser(c *Client, t *Transaction) (res []Transaction, err error) {
 	newUser := User{
-		ID:    t.GetField(fieldUserID).Data,
-		Name:  string(t.GetField(fieldUserName).Data),
-		Icon:  t.GetField(fieldUserIconID).Data,
-		Flags: t.GetField(fieldUserFlags).Data,
+		ID:    t.GetField(FieldUserID).Data,
+		Name:  string(t.GetField(FieldUserName).Data),
+		Icon:  t.GetField(FieldUserIconID).Data,
+		Flags: t.GetField(FieldUserFlags).Data,
 	}
 
 	// Possible cases:
@@ -383,7 +394,7 @@ func handleNotifyChangeUser(c *Client, t *Transaction) (res []Transaction, err e
 }
 
 func handleNotifyDeleteUser(c *Client, t *Transaction) (res []Transaction, err error) {
-	exitUser := t.GetField(fieldUserID).Data
+	exitUser := t.GetField(FieldUserID).Data
 
 	var newUserList []User
 	for _, u := range c.UserList {
@@ -399,59 +410,11 @@ func handleNotifyDeleteUser(c *Client, t *Transaction) (res []Transaction, err e
 	return res, err
 }
 
-const readBuffSize = 1024000 // 1KB - TODO: what should this be?
-
-func (c *Client) ReadLoop() error {
-	tranBuff := make([]byte, 0)
-	tReadlen := 0
-	// Infinite loop where take action on incoming client requests until the connection is closed
-	for {
-		buf := make([]byte, readBuffSize)
-		tranBuff = tranBuff[tReadlen:]
-
-		readLen, err := c.Connection.Read(buf)
-		if err != nil {
-			return err
-		}
-		tranBuff = append(tranBuff, buf[:readLen]...)
-
-		// We may have read multiple requests worth of bytes from Connection.Read.  readTransactions splits them
-		// into a slice of transactions
-		var transactions []Transaction
-		if transactions, tReadlen, err = readTransactions(tranBuff); err != nil {
-			c.Logger.Errorw("Error handling transaction", "err", err)
-		}
-
-		// iterate over all of the transactions that were parsed from the byte slice and handle them
-		for _, t := range transactions {
-			if err := c.HandleTransaction(&t); err != nil {
-				c.Logger.Errorw("Error handling transaction", "err", err)
-			}
-		}
-	}
-}
-
-func (c *Client) GetTransactions() error {
-	tranBuff := make([]byte, 0)
-	tReadlen := 0
-
-	buf := make([]byte, readBuffSize)
-	tranBuff = tranBuff[tReadlen:]
-
-	readLen, err := c.Connection.Read(buf)
-	if err != nil {
-		return err
-	}
-	tranBuff = append(tranBuff, buf[:readLen]...)
-
-	return nil
-}
-
 func handleClientGetUserNameList(c *Client, t *Transaction) (res []Transaction, err error) {
 	var users []User
 	for _, field := range t.Fields {
-		// The Hotline protocol docs say that ClientGetUserNameList should only return fieldUsernameWithInfo (300)
-		// fields, but shxd sneaks in fieldChatSubject (115) so it's important to filter explicitly for the expected
+		// The Hotline protocol docs say that ClientGetUserNameList should only return FieldUsernameWithInfo (300)
+		// fields, but shxd sneaks in FieldChatSubject (115) so it's important to filter explicitly for the expected
 		// field type.  Probably a good idea to do everywhere.
 		if bytes.Equal(field.ID, []byte{0x01, 0x2c}) {
 			u, err := ReadUser(field.Data)
@@ -482,19 +445,23 @@ func (c *Client) renderUserList() {
 }
 
 func handleClientChatMsg(c *Client, t *Transaction) (res []Transaction, err error) {
-	_, _ = fmt.Fprintf(c.UI.chatBox, "%s \n", t.GetField(fieldData).Data)
+	if c.Pref.EnableBell {
+		fmt.Println("\a")
+	}
+
+	_, _ = fmt.Fprintf(c.UI.chatBox, "%s \n", t.GetField(FieldData).Data)
 
 	return res, err
 }
 
 func handleClientTranUserAccess(c *Client, t *Transaction) (res []Transaction, err error) {
-	c.UserAccess = t.GetField(fieldUserAccess).Data
+	c.UserAccess = t.GetField(FieldUserAccess).Data
 
 	return res, err
 }
 
 func handleClientTranShowAgreement(c *Client, t *Transaction) (res []Transaction, err error) {
-	agreement := string(t.GetField(fieldData).Data)
+	agreement := string(t.GetField(FieldData).Data)
 	agreement = strings.ReplaceAll(agreement, "\r", "\n")
 
 	agreeModal := tview.NewModal().
@@ -504,11 +471,11 @@ func handleClientTranShowAgreement(c *Client, t *Transaction) (res []Transaction
 			if buttonIndex == 0 {
 				res = append(res,
 					*NewTransaction(
-						tranAgreed, nil,
-						NewField(fieldUserName, []byte(c.pref.Username)),
-						NewField(fieldUserIconID, c.pref.IconBytes()),
-						NewField(fieldUserFlags, []byte{0x00, 0x00}),
-						NewField(fieldOptions, []byte{0x00, 0x00}),
+						TranAgreed, nil,
+						NewField(FieldUserName, []byte(c.Pref.Username)),
+						NewField(FieldUserIconID, c.Pref.IconBytes()),
+						NewField(FieldUserFlags, []byte{0x00, 0x00}),
+						NewField(FieldOptions, []byte{0x00, 0x00}),
 					),
 				)
 				c.UI.Pages.HidePage("agreement")
@@ -527,7 +494,7 @@ func handleClientTranShowAgreement(c *Client, t *Transaction) (res []Transaction
 
 func handleClientTranLogin(c *Client, t *Transaction) (res []Transaction, err error) {
 	if !bytes.Equal(t.ErrorCode, []byte{0, 0, 0, 0}) {
-		errMsg := string(t.GetField(fieldError).Data)
+		errMsg := string(t.GetField(FieldError).Data)
 		errModal := tview.NewModal()
 		errModal.SetText(errMsg)
 		errModal.AddButtons([]string{"Oh no"})
@@ -539,22 +506,23 @@ func handleClientTranLogin(c *Client, t *Transaction) (res []Transaction, err er
 
 		c.UI.App.Draw() // TODO: errModal doesn't render without this.  wtf?
 
-		c.Logger.Error(string(t.GetField(fieldError).Data))
-		return nil, errors.New("login error: " + string(t.GetField(fieldError).Data))
+		c.Logger.Error(string(t.GetField(FieldError).Data))
+		return nil, errors.New("login error: " + string(t.GetField(FieldError).Data))
 	}
 	c.UI.Pages.AddAndSwitchToPage(serverUIPage, c.UI.renderServerUI(), true)
 	c.UI.App.SetFocus(c.UI.chatInput)
 
-	if err := c.Send(*NewTransaction(tranGetUserNameList, nil)); err != nil {
+	if err := c.Send(*NewTransaction(TranGetUserNameList, nil)); err != nil {
 		c.Logger.Errorw("err", "err", err)
 	}
 	return res, err
 }
 
 // JoinServer connects to a Hotline server and completes the login flow
-func (c *Client) JoinServer(address, login, passwd string) error {
+func (c *Client) Connect(address, login, passwd string) (err error) {
 	// Establish TCP connection to server
-	if err := c.connect(address); err != nil {
+	c.Connection, err = net.DialTimeout("tcp", address, 5*time.Second)
+	if err != nil {
 		return err
 	}
 
@@ -563,7 +531,7 @@ func (c *Client) JoinServer(address, login, passwd string) error {
 		return err
 	}
 
-	// Authenticate (send tranLogin 107)
+	// Authenticate (send TranLogin 107)
 	if err := c.LogIn(login, passwd); err != nil {
 		return err
 	}
@@ -574,22 +542,14 @@ func (c *Client) JoinServer(address, login, passwd string) error {
 	return nil
 }
 
+const keepaliveInterval = 300 * time.Second
+
 func (c *Client) keepalive() error {
 	for {
-		time.Sleep(300 * time.Second)
-		_ = c.Send(*NewTransaction(tranKeepAlive, nil))
-		c.Logger.Infow("Sent keepalive ping")
-	}
-}
-
-// connect establishes a connection with a Server by sending handshake sequence
-func (c *Client) connect(address string) error {
-	var err error
-	c.Connection, err = net.DialTimeout("tcp", address, 5*time.Second)
-	if err != nil {
-		return err
+		time.Sleep(keepaliveInterval)
+		_ = c.Send(*NewTransaction(TranKeepAlive, nil))
+		c.Logger.Debugw("Sent keepalive ping")
 	}
-	return nil
 }
 
 var ClientHandshake = []byte{
@@ -630,33 +590,29 @@ func (c *Client) Handshake() error {
 func (c *Client) LogIn(login string, password string) error {
 	return c.Send(
 		*NewTransaction(
-			tranLogin, nil,
-			NewField(fieldUserName, []byte(c.pref.Username)),
-			NewField(fieldUserIconID, c.pref.IconBytes()),
-			NewField(fieldUserLogin, negateString([]byte(login))),
-			NewField(fieldUserPassword, negateString([]byte(password))),
-			NewField(fieldVersion, []byte{0, 2}),
+			TranLogin, nil,
+			NewField(FieldUserName, []byte(c.Pref.Username)),
+			NewField(FieldUserIconID, c.Pref.IconBytes()),
+			NewField(FieldUserLogin, negateString([]byte(login))),
+			NewField(FieldUserPassword, negateString([]byte(password))),
 		),
 	)
 }
 
 func (c *Client) Send(t Transaction) error {
 	requestNum := binary.BigEndian.Uint16(t.Type)
-	tID := binary.BigEndian.Uint32(t.ID)
-
-	// handler := TransactionHandlers[requestNum]
 
 	// if transaction is NOT reply, add it to the list to transactions we're expecting a response for
 	if t.IsReply == 0 {
-		c.activeTasks[tID] = &t
+		c.activeTasks[binary.BigEndian.Uint32(t.ID)] = &t
 	}
 
-	var n int
-	var err error
 	b, err := t.MarshalBinary()
 	if err != nil {
 		return err
 	}
+
+	var n int
 	if n, err = c.Connection.Write(b); err != nil {
 		return err
 	}
@@ -676,21 +632,17 @@ func (c *Client) HandleTransaction(t *Transaction) error {
 		t.Type = origT.Type
 	}
 
-	requestNum := binary.BigEndian.Uint16(t.Type)
-	c.Logger.Infow(
-		"Received Transaction",
-		"RequestType", requestNum,
-	)
-
-	if handler, ok := c.Handlers[requestNum]; ok {
-		outT, _ := handler.Handle(c, t)
+	if handler, ok := c.Handlers[binary.BigEndian.Uint16(t.Type)]; ok {
+		outT, _ := handler(c, t)
 		for _, t := range outT {
-			c.Send(t)
+			if err := c.Send(t); err != nil {
+				return err
+			}
 		}
 	} else {
-		c.Logger.Errorw(
+		c.Logger.Debugw(
 			"Unimplemented transaction type received",
-			"RequestID", requestNum,
+			"RequestID", t.Type,
 			"TransactionID", t.ID,
 		)
 	}
@@ -701,3 +653,31 @@ func (c *Client) HandleTransaction(t *Transaction) error {
 func (c *Client) Disconnect() error {
 	return c.Connection.Close()
 }
+
+func (c *Client) HandleTransactions() error {
+	// Create a new scanner for parsing incoming bytes into transaction tokens
+	scanner := bufio.NewScanner(c.Connection)
+	scanner.Split(transactionScanner)
+
+	// Scan for new transactions and handle them as they come in.
+	for scanner.Scan() {
+		// Make a new []byte slice and copy the scanner bytes to it.  This is critical to avoid a data race as the
+		// scanner re-uses the buffer for subsequent scans.
+		buf := make([]byte, len(scanner.Bytes()))
+		copy(buf, scanner.Bytes())
+
+		var t Transaction
+		_, err := t.Write(buf)
+		if err != nil {
+			break
+		}
+		if err := c.HandleTransaction(&t); err != nil {
+			c.Logger.Errorw("Error handling transaction", "err", err)
+		}
+	}
+
+	if scanner.Err() == nil {
+		return scanner.Err()
+	}
+	return nil
+}