Remove some old cruft.

example/options/options_test.go

@@ -64,9 +64,7 @@ func TestOptions(t *testing.T) {
 	}
 
 	var b bytes.Buffer
-	if err := options.Append(&b); err != nil {
-		t.Fatal(err)
-	}
+	options.Append(&b)
 	if amt, err := sock.Write(b.Bytes()); err != nil || amt != b.Len() {
 		t.Fatal(err)
 	}

sip/addr.go

@@ -48,9 +48,6 @@ func ParseAddrBytes(s []byte) (addr *Addr, err error) {
 }
 
 func (addr *Addr) String() string {
-	if addr == nil {
-		return ""
-	}
 	var b bytes.Buffer
 	addr.Append(&b)
 	return b.String()
@@ -71,7 +68,10 @@ func (addr *Addr) Tag() *Addr {
 }
 
 // Reassembles a SIP address into a buffer.
-func (addr *Addr) Append(b *bytes.Buffer) error {
+func (addr *Addr) Append(b *bytes.Buffer) {
+	if addr == nil {
+		return
+	}
 	if addr.Display != "" {
 		appendQuoted(b, []byte(addr.Display))
 		b.WriteByte(' ')
@@ -85,7 +85,6 @@ func (addr *Addr) Append(b *bytes.Buffer) error {
 		b.WriteByte(' ')
 		addr.Next.Append(b)
 	}
-	return nil
 }
 
 // Deep copies a new Addr object.

sip/msg.go

@@ -4,8 +4,6 @@ package sip
 
 import (
 	"bytes"
-	"errors"
-	"log"
 	"net"
 	"strconv"
 )
@@ -88,18 +86,12 @@ type Msg struct {
 //go:generate ragel -Z -G2 -o msg_parse.go msg_parse.rl
 
 func (msg *Msg) IsResponse() bool {
-	return msg.Method == ""
+	return msg.Status > 0
 }
 
 func (msg *Msg) String() string {
-	if msg == nil {
-		return ""
-	}
 	var b bytes.Buffer
-	if err := msg.Append(&b); err != nil {
-		log.Println("Bad SIP message!", err)
-		return ""
-	}
+	msg.Append(&b)
 	return b.String()
 }
 
@@ -126,17 +118,23 @@ func (msg *Msg) Copy() *Msg {
 }
 
 // I turn a SIP message back into a packet.
-func (msg *Msg) Append(b *bytes.Buffer) error {
+func (msg *Msg) Append(b *bytes.Buffer) {
+	if msg == nil {
+		return
+	}
 	if !msg.IsResponse() {
 		if msg.Method == "" {
-			return errors.New("Msg.Method not set")
+			b.WriteString("INVITE ")
+		} else {
+			b.WriteString(msg.Method)
+			b.WriteString(" ")
 		}
 		if msg.Request == nil {
-			return errors.New("msg.Request not set")
+			// In case of bugs, keep calm and DDOS NASA.
+			b.WriteString("sip:www.nasa.gov:80")
+		} else {
+			msg.Request.Append(b)
 		}
-		b.WriteString(msg.Method)
-		b.WriteString(" ")
-		msg.Request.Append(b)
 		b.WriteString(" ")
 		msg.appendVersion(b)
 		b.WriteString("\r\n")
@@ -162,25 +160,19 @@ func (msg *Msg) Append(b *bytes.Buffer) error {
 
 	for viap := msg.Via; viap != nil; viap = viap.Next {
 		b.WriteString("Via: ")
-		if err := viap.Append(b); err != nil {
-			return err
-		}
+		viap.Append(b)
 		b.WriteString("\r\n")
 	}
 
 	if msg.Route != nil {
 		b.WriteString("Route: ")
-		if err := msg.Route.Append(b); err != nil {
-			return err
-		}
+		msg.Route.Append(b)
 		b.WriteString("\r\n")
 	}
 
 	if msg.RecordRoute != nil {
 		b.WriteString("Record-Route: ")
-		if err := msg.RecordRoute.Append(b); err != nil {
-			return err
-		}
+		msg.RecordRoute.Append(b)
 		b.WriteString("\r\n")
 	}
 
@@ -466,8 +458,6 @@ func (msg *Msg) Append(b *bytes.Buffer) error {
 	} else {
 		b.WriteString("Content-Length: 0\r\n\r\n")
 	}
-
-	return nil
 }
 
 func (msg *Msg) appendVersion(b *bytes.Buffer) {

sip/uri.go

@@ -22,7 +22,6 @@ package sip
 
 import (
 	"bytes"
-	"errors"
 	"github.com/jart/gosip/util"
 )
 
@@ -30,12 +29,6 @@ const (
 	delims = ":/@;?#<>"
 )
 
-var (
-	URISchemeNotFound = errors.New("scheme not found")
-	URIMissingHost    = errors.New("host missing")
-	URIBadPort        = errors.New("invalid port number")
-)
-
 type URI struct {
 	Scheme string     // e.g. sip, sips, tel, etc.
 	User   string     // e.g. sip:USER@host
@@ -63,15 +56,15 @@ func (uri *URI) Copy() *URI {
 // TODO(jart): URI Comparison https://tools.ietf.org/html/rfc3261#section-19.1.4
 
 func (uri *URI) String() string {
-	if uri == nil {
-		return "<nil>"
-	}
 	var b bytes.Buffer
 	uri.Append(&b)
 	return b.String()
 }
 
 func (uri *URI) Append(b *bytes.Buffer) {
+	if uri == nil {
+		return
+	}
 	if uri.Scheme == "" {
 		b.WriteString("sip:")
 	} else {

sip/via.go

@@ -4,16 +4,10 @@ package sip
 
 import (
 	"bytes"
-	"errors"
 	"github.com/jart/gosip/util"
 	"strconv"
 )
 
-var (
-	ViaBadHeader  = errors.New("Bad Via header")
-	ViaProtoBlank = errors.New("Via Transport blank")
-)
-
 // Example: SIP/2.0/UDP 1.2.3.4:5060;branch=z9hG4bK556f77e6.
 type Via struct {
 	Protocol  string // should be "SIP"
@@ -25,10 +19,7 @@ type Via struct {
 	Next      *Via   // pointer to next via header if any
 }
 
-func (via *Via) Append(b *bytes.Buffer) error {
-	if via.Host == "" {
-		return ViaProtoBlank
-	}
+func (via *Via) Append(b *bytes.Buffer) {
 	if via.Protocol == "" {
 		b.WriteString("SIP/")
 	} else {
@@ -53,7 +44,6 @@ func (via *Via) Append(b *bytes.Buffer) error {
 		b.WriteString(strconv.Itoa(int(via.Port)))
 	}
 	via.Param.Append(b)
-	return nil
 }
 
 // Copy returns a deep copy of via.