limit buffer usage

Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>

encoding.go

@@ -244,16 +244,11 @@ func (enc *TightPngEncoding) Read(c Conn, rect *Rectangle) error {
 	cmp := enc.TightCC.Compression
 	switch cmp {
 	case TightCompressionPNG:
-		buf := bytes.NewBuffer(nil)
 		l, err := readTightLength(c)
 		if err != nil {
 			return err
 		}
-		_, err = io.CopyN(buf, c, int64(l))
+		enc.Image, err = png.Decode(io.LimitReader(c, int64(l)))
-		if err != nil {
-			return err
-		}
-		enc.Image, err = png.Decode(buf)
 		if err != nil {
 			return err
 		}

example/proxy/main.go

@@ -4,11 +4,17 @@ import (
 	"context"
 	"log"
 	"net"
+	"net/http"
+	_ "net/http/pprof"
 
 	vnc "github.com/vtolstov/go-vnc"
 )
 
 func main() {
+	go func() {
+		log.Println(http.ListenAndServe(":6060", nil))
+	}()
+
 	ln, err := net.Listen("tcp", ":5900")
 	if err != nil {
 		log.Fatalf("Error listen. %v", err)

image.go

@@ -114,6 +114,7 @@ func colorsToImage(x, y, width, height uint16, colors []Color) *image.RGBA64 {
 
 // Marshal implements the Marshaler interface.
 func (r *Rectangle) Write(c Conn) error {
+
 	var err error
 	if err = binary.Write(c, binary.BigEndian, r.X); err != nil {
 		return err
@@ -131,10 +132,7 @@ func (r *Rectangle) Write(c Conn) error {
 		return err
 	}
 
-	if err := r.Enc.Write(c, r); err != nil {
+	return r.Enc.Write(c, r)
-		return err
-	}
-	return c.Flush()
 }
 
 func (r *Rectangle) Read(c Conn) error {

server.go

@@ -416,10 +416,7 @@ func (*Bell) Read(c Conn) (ServerMessage, error) {
 }
 
 func (msg *Bell) Write(c Conn) error {
-	if err := binary.Write(c, binary.BigEndian, msg.Type()); err != nil {
+	return binary.Write(c, binary.BigEndian, msg.Type())
-		return err
-	}
-	return c.Flush()
 }
 
 type SetColorMapEntries struct {