A working proxy exists.

packages/ipp/resolution.go

@@ -1,67 +1,95 @@
 package ipp
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/binary"
 	"fmt"
-	"io"
+
+	log "github.com/sirupsen/logrus"
 )
 
-type resolution struct {
-	name                string
-	crossFeedResolution int32
-	feedResolution      int32
-	units               int8
+// Resolution represents a ipp resolution attribute
+type Resolution struct {
+	CrossFeedResolution int32
+	FeedResolution      int32
+	Unit                int8 // 3 seems to mean dpi (rfc3805)
 }
 
-func NewResolution(name string, xfres int32, fres int32) *resolution {
-	r := new(resolution)
+// SetOfResolutions represents a set ipp resolution attributes
+type SetOfResolutions struct {
+	name string
+	sor  []Resolution
+}
+
+// NewSetOfResolution creats a new set of ipp resolution attributes
+func NewSetOfResolution(name string, resSet ...Resolution) *SetOfResolutions {
+	r := new(SetOfResolutions)
 	r.name = name
-	r.crossFeedResolution = xfres
-	r.feedResolution = fres
-	r.units = 3 // 3 seems to mean dpi (rfc3805)
+	r.sor = resSet
 	return r
 }
 
-func (r *resolution) unmarshal(byteStream io.Reader) {
+func (r *SetOfResolutions) unmarshal(byteStream *bufio.Reader) {
 	var length uint16
-	binary.Read(byteStream, binary.BigEndian, &length)
-	attributeName := make([]byte, length)
-	if length > 0 {
-		binary.Read(byteStream, binary.BigEndian, attributeName)
+	var res Resolution
+	for {
+		binary.Read(byteStream, binary.BigEndian, &length)
+		attributeName := make([]byte, length)
+		if length > 0 {
+			binary.Read(byteStream, binary.BigEndian, attributeName)
+			r.name = string(attributeName)
+		}
+		binary.Read(byteStream, binary.BigEndian, &length)
+		if length != 9 {
+			panic("Wrong length in resolution")
+		}
+		binary.Read(byteStream, binary.BigEndian, &res.CrossFeedResolution)
+		binary.Read(byteStream, binary.BigEndian, &res.FeedResolution)
+		binary.Read(byteStream, binary.BigEndian, &res.Unit)
+		r.sor = append(r.sor, res)
+		var t tag
+		err := binary.Read(byteStream, binary.BigEndian, &t)
+		if err != nil {
+			log.Error(err.Error())
+		}
+		if t != resolutionValueTag {
+			byteStream.UnreadByte()
+			return
+		}
 	}
-	r.name = string(attributeName)
-	binary.Read(byteStream, binary.BigEndian, &length)
-	if length != 9 {
-		panic("Wrong length in resolution")
-	}
-	binary.Read(byteStream, binary.BigEndian, &r.crossFeedResolution)
-	binary.Read(byteStream, binary.BigEndian, &r.feedResolution)
-	binary.Read(byteStream, binary.BigEndian, &r.units)
 }
 
-func (r resolution) Name() string {
+// Name returns the name of the attribute
+func (r SetOfResolutions) Name() string {
 	return r.name
 }
 
-func (r resolution) String() string {
-	return fmt.Sprintf("%v:%v,%v,%v", r.name, r.crossFeedResolution, r.feedResolution, r.units)
+func (r SetOfResolutions) String() string {
+	return fmt.Sprintf("%v:%v", r.name, r.sor)
 }
 
-func (r *resolution) marshal() []byte {
+func (r *SetOfResolutions) marshal() []byte {
 
-	b := make([]byte, 0, 14+len(r.name))
+	b := make([]byte, 0, 14+len(r.name)+14*(len(r.sor)-1))
 	buf := bytes.NewBuffer(b)
-	buf.WriteByte(byte(resolutionValueTag))
-	binary.Write(buf, binary.BigEndian, uint16(len(r.name)))
-	buf.WriteString(r.name)
-	binary.Write(buf, binary.BigEndian, uint16(9))
-	binary.Write(buf, binary.BigEndian, int32(r.crossFeedResolution))
-	binary.Write(buf, binary.BigEndian, int32(r.feedResolution))
-	buf.WriteByte(byte(r.units))
+
+	for i, res := range r.sor {
+		buf.WriteByte(byte(resolutionValueTag))
+		if i == 0 {
+			binary.Write(buf, binary.BigEndian, uint16(len(r.name)))
+			buf.WriteString(r.name)
+		} else {
+			binary.Write(buf, binary.BigEndian, uint16(0))
+		}
+		binary.Write(buf, binary.BigEndian, uint16(9))
+		binary.Write(buf, binary.BigEndian, int32(res.CrossFeedResolution))
+		binary.Write(buf, binary.BigEndian, int32(res.FeedResolution))
+		buf.WriteByte(byte(res.Unit))
+	}
 	return buf.Bytes()
 }
 
-func (r *resolution) valueTag() tag {
+func (r *SetOfResolutions) valueTag() tag {
 	return resolutionValueTag
 }