replace with optional function pattern

.gitignore

@@ -1,3 +1,5 @@
 *.exe
+*~
+default.pgo
 tags
 tmp/

advertise.go

@@ -39,12 +39,16 @@ type Advertiser struct {
 
 // Advertise starts advertisement of service.
 // location should be a string or a ssdp.LocationProvider.
-func Advertise(st, usn string, location interface{}, server string, maxAge int, opts ...AdvertiserOption) (*Advertiser, error) {
+func Advertise(st, usn string, location interface{}, server string, maxAge int, opts ...Option) (*Advertiser, error) {
 	locProv, err := toLocationProvider(location)
 	if err != nil {
 		return nil, err
 	}
-	conn, err := multicast.Listen(multicast.RecvAddrResolver, defaultConnOpts()...)
+	cfg, err := opts2config(opts)
+	if err != nil {
+		return nil, err
+	}
+	conn, err := multicast.Listen(multicast.RecvAddrResolver, cfg.multicastConfig.options()...)
 	if err != nil {
 		return nil, err
 	}
@@ -57,9 +61,7 @@ func Advertise(st, usn string, location interface{}, server string, maxAge int,
 		maxAge:  maxAge,
 		conn:    conn,
 		ch:      make(chan *message),
-	}
-	for _, o := range opts {
-		o.apply(a)
+		addHost: cfg.advertiseConfig.addHost,
 	}
 	a.wg.Add(2)
 	a.wgS.Add(1)
@@ -202,23 +204,3 @@ func (a *Advertiser) Bye() error {
 	ssdplog.Printf("sent bye")
 	return nil
 }
-
-// AdvertiserOption configures for specific behavior of Advertiser.
-type AdvertiserOption interface {
-	apply(*Advertiser)
-}
-
-type advertiserOptionFunc func(*Advertiser)
-
-func (af advertiserOptionFunc) apply(a *Advertiser) {
-	af(a)
-}
-
-// AdvertiserOptionAddHost returns as AdvertiserOption that add HOST header
-// response for M-SEARCH request.  This is added to support SmartThings.
-// See https://github.com/koron/go-ssdp/issues/30 for details.
-func AdvertiserOptionAddHost() AdvertiserOption {
-	return advertiserOptionFunc(func(a *Advertiser) {
-		a.addHost = true
-	})
-}

announce.go

@@ -10,13 +10,17 @@ import (
 
 // AnnounceAlive sends ssdp:alive message.
 // location should be a string or a ssdp.LocationProvider.
-func AnnounceAlive(nt, usn string, location interface{}, server string, maxAge int, localAddr string) error {
+func AnnounceAlive(nt, usn string, location interface{}, server string, maxAge int, localAddr string, opts ...Option) error {
 	locProv, err := toLocationProvider(location)
 	if err != nil {
 		return err
 	}
+	cfg, err := opts2config(opts)
+	if err != nil {
+		return err
+	}
 	// dial multicast UDP packet.
-	conn, err := multicast.Listen(&multicast.AddrResolver{Addr: localAddr}, defaultConnOpts()...)
+	conn, err := multicast.Listen(&multicast.AddrResolver{Addr: localAddr}, cfg.multicastConfig.options()...)
 	if err != nil {
 		return err
 	}
@@ -75,9 +79,13 @@ func buildAlive(raddr net.Addr, nt, usn, location, server string, maxAge int) []
 }
 
 // AnnounceBye sends ssdp:byebye message.
-func AnnounceBye(nt, usn, localAddr string) error {
+func AnnounceBye(nt, usn, localAddr string, opts...Option) error {
+	cfg, err := opts2config(opts)
+	if err != nil {
+		return err
+	}
 	// dial multicast UDP packet.
-	conn, err := multicast.Listen(&multicast.AddrResolver{Addr: localAddr}, defaultConnOpts()...)
+	conn, err := multicast.Listen(&multicast.AddrResolver{Addr: localAddr}, cfg.multicastConfig.options()...)
 	if err != nil {
 		return err
 	}

examples/advertise/advertise.go

@@ -29,14 +29,16 @@ func main() {
 	if *v {
 		ssdp.Logger = log.New(os.Stderr, "[SSDP] ", log.LstdFlags)
 	}
+
+	var opts []ssdp.Option
 	if *ttl > 0 {
-		ssdp.SetMulticastTTL(*ttl)
+		opts = append(opts, ssdp.TTL(*ttl))
 	}
 	if *sysIf {
-		ssdp.SetMulticastSystemAssignedInterface(true)
+		opts = append(opts, ssdp.OnlySystemInterface())
 	}
 
-	ad, err := ssdp.Advertise(*st, *usn, *loc, *srv, *maxAge)
+	ad, err := ssdp.Advertise(*st, *usn, *loc, *srv, *maxAge, opts...)
 	if err != nil {
 		log.Fatal(err)
 	}

examples/alive/alive.go

@@ -28,14 +28,16 @@ func main() {
 	if *v {
 		ssdp.Logger = log.New(os.Stderr, "[SSDP] ", log.LstdFlags)
 	}
+
+	var opts []ssdp.Option
 	if *ttl > 0 {
-		ssdp.SetMulticastTTL(*ttl)
+		opts = append(opts, ssdp.TTL(*ttl))
 	}
 	if *sysIf {
-		ssdp.SetMulticastSystemAssignedInterface(true)
+		opts = append(opts, ssdp.OnlySystemInterface())
 	}
 
-	err := ssdp.AnnounceAlive(*nt, *usn, *loc, *srv, *maxAge, *laddr)
+	err := ssdp.AnnounceAlive(*nt, *usn, *loc, *srv, *maxAge, *laddr, opts...)
 	if err != nil {
 		log.Fatal(err)
 	}

examples/bye/bye.go

@@ -25,14 +25,16 @@ func main() {
 	if *v {
 		ssdp.Logger = log.New(os.Stderr, "[SSDP] ", log.LstdFlags)
 	}
+
+	var opts []ssdp.Option
 	if *ttl > 0 {
-		ssdp.SetMulticastTTL(*ttl)
+		opts = append(opts, ssdp.TTL(*ttl))
 	}
 	if *sysIf {
-		ssdp.SetMulticastSystemAssignedInterface(true)
+		opts = append(opts, ssdp.OnlySystemInterface())
 	}
 
-	err := ssdp.AnnounceBye(*nt, *usn, *laddr)
+	err := ssdp.AnnounceBye(*nt, *usn, *laddr, opts...)
 	if err != nil {
 		log.Fatal(err)
 	}

examples/monitor/monitor.go

@@ -25,17 +25,20 @@ func main() {
 	if *v {
 		ssdp.Logger = log.New(os.Stderr, "[SSDP] ", log.LstdFlags)
 	}
+
+	var opts []ssdp.Option
 	if *ttl > 0 {
-		ssdp.SetMulticastTTL(*ttl)
+		opts = append(opts, ssdp.TTL(*ttl))
 	}
 	if *sysIf {
-		ssdp.SetMulticastSystemAssignedInterface(true)
+		opts = append(opts, ssdp.OnlySystemInterface())
 	}
 
 	m := &ssdp.Monitor{
-		Alive:  onAlive,
-		Bye:    onBye,
-		Search: onSearch,
+		Alive:   onAlive,
+		Bye:     onBye,
+		Search:  onSearch,
+		Options: opts,
 	}
 	if err := m.Start(); err != nil {
 		log.Fatal(err)

examples/search/search.go

@@ -25,13 +25,16 @@ func main() {
 	if *v {
 		ssdp.Logger = log.New(os.Stderr, "[SSDP] ", log.LstdFlags)
 	}
+
+	var opts []ssdp.Option
 	if *ttl > 0 {
-		ssdp.SetMulticastTTL(*ttl)
+		opts = append(opts, ssdp.TTL(*ttl))
 	}
 	if *sysIf {
-		ssdp.SetMulticastSystemAssignedInterface(true)
+		opts = append(opts, ssdp.OnlySystemInterface())
 	}
-	list, err := ssdp.Search(*t, *w, *l)
+
+	list, err := ssdp.Search(*t, *w, *l, opts...)
 	if err != nil {
 		log.Fatal(err)
 	}

monitor.go

@@ -20,13 +20,19 @@ type Monitor struct {
 	Bye    ByeHandler
 	Search SearchHandler
 
+	Options []Option
+
 	conn *multicast.Conn
 	wg   sync.WaitGroup
 }
 
 // Start starts to monitor SSDP messages.
 func (m *Monitor) Start() error {
-	conn, err := multicast.Listen(multicast.RecvAddrResolver, defaultConnOpts()...)
+	cfg, err := opts2config(m.Options)
+	if err != nil {
+		return err
+	}
+	conn, err := multicast.Listen(multicast.RecvAddrResolver, cfg.multicastConfig.options()...)
 	if err != nil {
 		return err
 	}

option.go

@@ -0,0 +1,77 @@
+package ssdp
+
+import "github.com/koron/go-ssdp/internal/multicast"
+
+type config struct {
+	multicastConfig
+	advertiseConfig
+}
+
+func opts2config(opts []Option) (cfg config, err error) {
+	for _, o := range opts {
+		err := o.apply(&cfg)
+		if err != nil {
+			return config{}, err
+		}
+	}
+	return cfg, nil
+}
+
+type multicastConfig struct {
+	ttl   int
+	sysIf bool
+}
+
+func (mc multicastConfig) options() (opts []multicast.ConnOption) {
+	if mc.ttl > 0 {
+		opts = append(opts, multicast.ConnTTL(mc.ttl))
+	}
+	if mc.sysIf {
+		opts = append(opts, multicast.ConnSystemAssginedInterface())
+	}
+	return opts
+}
+
+type advertiseConfig struct {
+	addHost bool
+}
+
+// Option is option set for SSDP API.
+type Option interface {
+	apply(c *config) error
+}
+
+type optionFunc func(*config) error
+
+func (of optionFunc) apply(c *config) error {
+	return of(c)
+}
+
+// TTL returns as Option that set TTL for multicast packets.
+func TTL(ttl int) Option {
+	return optionFunc(func(c *config) error {
+		c.ttl = ttl
+		return nil
+	})
+}
+
+// OnlySystemInterface returns as Option that using only a system assigned
+// multicast interface.
+func OnlySystemInterface() Option {
+	return optionFunc(func(c *config) error {
+		c.sysIf = true
+		return nil
+	})
+}
+
+// AdvertiseHost returns as Option that add HOST header to response for
+// M-SEARCH requests.
+// This option works with Advertise() function only.
+// This is added to support SmartThings.
+// See https://github.com/koron/go-ssdp/issues/30 for details.
+func AdvertiseHost() Option {
+	return optionFunc(func(c *config) error {
+		c.addHost = true
+		return nil
+	})
+}

search.go

@@ -69,9 +69,13 @@ const (
 )
 
 // Search searches services by SSDP.
-func Search(searchType string, waitSec int, localAddr string) ([]Service, error) {
+func Search(searchType string, waitSec int, localAddr string, opts ...Option) ([]Service, error) {
+	cfg, err := opts2config(opts)
+	if err != nil {
+		return nil, err
+	}
 	// dial multicast UDP packet.
-	conn, err := multicast.Listen(&multicast.AddrResolver{Addr: localAddr}, defaultConnOpts()...)
+	conn, err := multicast.Listen(&multicast.AddrResolver{Addr: localAddr}, cfg.multicastConfig.options()...)
 	if err != nil {
 		return nil, err
 	}

search_test.go

@@ -177,7 +177,7 @@ func TestSearch_ServiceRawHeader(t *testing.T) {
 }
 
 func TestSearch_AdvetiserWithHost(t *testing.T) {
-	a, err := Advertise("test:search+advertiserwithhost", "usn:search+advertiserwithhost", "location:search+advertiserwithhost", "server:search+advertiserwithhost", 600, AdvertiserOptionAddHost())
+	a, err := Advertise("test:search+advertiserwithhost", "usn:search+advertiserwithhost", "location:search+advertiserwithhost", "server:search+advertiserwithhost", 600, AdvertiseHost())
 	if err != nil {
 		t.Fatalf("failed to Advertise: %s", err)
 	}

ssdp.go

@@ -35,37 +35,3 @@ func SetMulticastRecvAddrIPv4(addr string) error {
 func SetMulticastSendAddrIPv4(addr string) error {
 	return multicast.SetSendAddrIPv4(addr)
 }
-
-func defaultConnOpts() []multicast.ConnOption {
-	var opts []multicast.ConnOption
-	if multicastTTL > 0 {
-		opts = append(opts, multicast.ConnTTL(multicastTTL))
-	}
-	if multicastSystemAssignedInterface {
-		opts = append(opts, multicast.ConnSystemAssginedInterface())
-	}
-	return opts
-}
-
-var multicastTTL int
-
-// SetMulticastTTL sets default TTL of SSDP's UDP packets.
-// 0 default, 1 or greater set TTL.
-func SetMulticastTTL(ttl int) {
-	multicastTTL = ttl
-}
-
-var multicastSystemAssignedInterface bool
-
-// SetMulticastSystemAssignedInterface updates state whether using the system
-// assigned multicast interface or provided interfaces.
-// Default is "false", it uses provided interface (see Interfaces also).
-func SetMulticastSystemAssignedInterface(enable bool) {
-	multicastSystemAssignedInterface = enable
-}
-
-// GetMulticastSystemAssignedInterface returns state using the system assigned
-// multicast interface or provided interfaces.
-func GetMulticastSystemAssignedInterface() bool {
-	return multicastSystemAssignedInterface
-}