update go-sql-driver/mysql vendor files

vendor/github.com/go-sql-driver/mysql/infile.go

@@ -9,23 +9,20 @@
 package mysql
 
 import (
-	"database/sql/driver"
 	"fmt"
 	"io"
 	"os"
 	"strings"
+	"sync"
 )
 
 var (
-	fileRegister   map[string]bool
-	readerRegister map[string]func() io.Reader
+	fileRegister       map[string]bool
+	fileRegisterLock   sync.RWMutex
+	readerRegister     map[string]func() io.Reader
+	readerRegisterLock sync.RWMutex
 )
 
-func init() {
-	fileRegister = make(map[string]bool)
-	readerRegister = make(map[string]func() io.Reader)
-}
-
 // RegisterLocalFile adds the given file to the file whitelist,
 // so that it can be used by "LOAD DATA LOCAL INFILE <filepath>".
 // Alternatively you can allow the use of all local files with
@@ -38,12 +35,21 @@ func init() {
 //  ...
 //
 func RegisterLocalFile(filePath string) {
+	fileRegisterLock.Lock()
+	// lazy map init
+	if fileRegister == nil {
+		fileRegister = make(map[string]bool)
+	}
+
 	fileRegister[strings.Trim(filePath, `"`)] = true
+	fileRegisterLock.Unlock()
 }
 
 // DeregisterLocalFile removes the given filepath from the whitelist.
 func DeregisterLocalFile(filePath string) {
+	fileRegisterLock.Lock()
 	delete(fileRegister, strings.Trim(filePath, `"`))
+	fileRegisterLock.Unlock()
 }
 
 // RegisterReaderHandler registers a handler function which is used
@@ -62,91 +68,115 @@ func DeregisterLocalFile(filePath string) {
 //  ...
 //
 func RegisterReaderHandler(name string, handler func() io.Reader) {
+	readerRegisterLock.Lock()
+	// lazy map init
+	if readerRegister == nil {
+		readerRegister = make(map[string]func() io.Reader)
+	}
+
 	readerRegister[name] = handler
+	readerRegisterLock.Unlock()
 }
 
 // DeregisterReaderHandler removes the ReaderHandler function with
 // the given name from the registry.
 func DeregisterReaderHandler(name string) {
+	readerRegisterLock.Lock()
 	delete(readerRegister, name)
+	readerRegisterLock.Unlock()
+}
+
+func deferredClose(err *error, closer io.Closer) {
+	closeErr := closer.Close()
+	if *err == nil {
+		*err = closeErr
+	}
 }
 
 func (mc *mysqlConn) handleInFileRequest(name string) (err error) {
 	var rdr io.Reader
-	data := make([]byte, 4+mc.maxWriteSize)
+	var data []byte
+	packetSize := 16 * 1024 // 16KB is small enough for disk readahead and large enough for TCP
+	if mc.maxWriteSize < packetSize {
+		packetSize = mc.maxWriteSize
+	}
 
-	if strings.HasPrefix(name, "Reader::") { // io.Reader
-		name = name[8:]
+	if idx := strings.Index(name, "Reader::"); idx == 0 || (idx > 0 && name[idx-1] == '/') { // io.Reader
+		// The server might return an an absolute path. See issue #355.
+		name = name[idx+8:]
+
+		readerRegisterLock.RLock()
 		handler, inMap := readerRegister[name]
-		if handler != nil {
+		readerRegisterLock.RUnlock()
+
+		if inMap {
 			rdr = handler()
-		}
-		if rdr == nil {
-			if !inMap {
-				err = fmt.Errorf("Reader '%s' is not registered", name)
+			if rdr != nil {
+				if cl, ok := rdr.(io.Closer); ok {
+					defer deferredClose(&err, cl)
+				}
 			} else {
 				err = fmt.Errorf("Reader '%s' is <nil>", name)
 			}
+		} else {
+			err = fmt.Errorf("Reader '%s' is not registered", name)
 		}
 	} else { // File
 		name = strings.Trim(name, `"`)
-		if mc.cfg.allowAllFiles || fileRegister[name] {
-			rdr, err = os.Open(name)
+		fileRegisterLock.RLock()
+		fr := fileRegister[name]
+		fileRegisterLock.RUnlock()
+		if mc.cfg.AllowAllFiles || fr {
+			var file *os.File
+			var fi os.FileInfo
+
+			if file, err = os.Open(name); err == nil {
+				defer deferredClose(&err, file)
+
+				// get file size
+				if fi, err = file.Stat(); err == nil {
+					rdr = file
+					if fileSize := int(fi.Size()); fileSize < packetSize {
+						packetSize = fileSize
+					}
+				}
+			}
 		} else {
-			err = fmt.Errorf("Local File '%s' is not registered. Use the DSN parameter 'allowAllFiles=true' to allow all files", name)
+			err = fmt.Errorf("local file '%s' is not registered", name)
 		}
 	}
 
-	if rdc, ok := rdr.(io.ReadCloser); ok {
-		defer func() {
-			if err == nil {
-				err = rdc.Close()
-			} else {
-				rdc.Close()
-			}
-		}()
-	}
-
 	// send content packets
-	var ioErr error
 	if err == nil {
+		data := make([]byte, 4+packetSize)
 		var n int
-		for err == nil && ioErr == nil {
+		for err == nil {
 			n, err = rdr.Read(data[4:])
 			if n > 0 {
-				data[0] = byte(n)
-				data[1] = byte(n >> 8)
-				data[2] = byte(n >> 16)
-				data[3] = mc.sequence
-				ioErr = mc.writePacket(data[:4+n])
+				if ioErr := mc.writePacket(data[:4+n]); ioErr != nil {
+					return ioErr
+				}
 			}
 		}
 		if err == io.EOF {
 			err = nil
 		}
-		if ioErr != nil {
-			errLog.Print(ioErr.Error())
-			return driver.ErrBadConn
-		}
 	}
 
 	// send empty packet (termination)
-	ioErr = mc.writePacket([]byte{
-		0x00,
-		0x00,
-		0x00,
-		mc.sequence,
-	})
-	if ioErr != nil {
-		errLog.Print(ioErr.Error())
-		return driver.ErrBadConn
+	if data == nil {
+		data = make([]byte, 4)
+	}
+	if ioErr := mc.writePacket(data[:4]); ioErr != nil {
+		return ioErr
 	}
 
 	// read OK packet
 	if err == nil {
-		return mc.readResultOK()
-	} else {
-		mc.readPacket()
+		_, err = mc.readResultOK()
+		return err
 	}
+
+	mc.readPacket()
 	return err
 }