voice: Allow setting udp.DialFunc

This commit fixes up the SetDialer method to accept a udp.DialFunc
instead of just a regular *net.Dialer, which is more flexible in that
the user can now control the UDP packet frequency properly.

voice/session.go

@@ -2,7 +2,6 @@ package voice
 
 import (
 	"context"
-	"net"
 	"sync"
 	"time"
 
@@ -66,10 +65,6 @@ var (
 	_ MainSession = (*state.State)(nil)
 )
 
-// UDPDialer is the UDP dialer function type. It's the function signature for
-// udp.DialConnection.
-type UDPDialer = func(ctx context.Context, addr string, ssrc uint32) (*udp.Connection, error)
-
 // Session is a single voice session that wraps around the voice gateway and UDP
 // connection.
 type Session struct {
@@ -146,7 +141,7 @@ func NewSessionCustom(ses MainSession, userID discord.UserID) *Session {
 
 // SetUDPDialer sets the given dialer to be used for dialing UDP voice
 // connections.
-func (s *Session) SetUDPDialer(d *net.Dialer) {
+func (s *Session) SetUDPDialer(d udp.DialFunc) {
 	s.udpManager.SetDialer(d)
 }
 

voice/udp/connection.go

@@ -17,9 +17,10 @@ import (
 // to decrypt.
 var ErrDecryptionFailed = errors.New("decryption failed")
 
-// Dialer is the default dialer that this package uses for all its dialing.
-var Dialer = net.Dialer{
-	Timeout: 10 * time.Second,
+// defaultDialer is the default dialer that this package uses for all its
+// dialing.
+var defaultDialer = net.Dialer{
+	Timeout: 30 * time.Second,
 }
 
 // Connection represents a voice connection. It is not thread-safe.
@@ -51,10 +52,31 @@ type Connection struct {
 	closed sync.Once
 }
 
+// DialFunc is the UDP dialer function type. It's the function signature for
+// udp.DialConnection.
+type DialFunc = func(ctx context.Context, addr string, ssrc uint32) (*Connection, error)
+
+// Assert that this is the same.
+var _ DialFunc = DialConnection
+
+// DialFuncWithFrequency creates a new DialFunc with the given frame duration
+// and time increment. See Connection's ResetFrequency method for more
+// information.
+func DialFuncWithFrequency(frameDuration time.Duration, timeIncr uint32) DialFunc {
+	return func(ctx context.Context, addr string, ssrc uint32) (*Connection, error) {
+		u, err := DialConnection(ctx, addr, ssrc)
+		if err != nil {
+			return nil, err
+		}
+		u.ResetFrequency(frameDuration, timeIncr)
+		return u, nil
+	}
+}
+
 // DialConnection dials the UDP connection using the given address and SSRC
 // number.
 func DialConnection(ctx context.Context, addr string, ssrc uint32) (*Connection, error) {
-	return DialConnectionCustom(ctx, &Dialer, addr, ssrc)
+	return DialConnectionCustom(ctx, &defaultDialer, addr, ssrc)
 }
 
 // DialConnectionCustom dials the UDP connection with a custom dialer.

voice/udp/manager.go

@@ -2,7 +2,6 @@ package udp
 
 import (
 	"context"
-	"net"
 	"sync"
 	"time"
 
@@ -21,7 +20,7 @@ var ErrDialWhileUnpaused = errors.New("dial is called while manager is not pause
 // Manager manages a UDP connection. It allows reconnecting. A Manager instance
 // is thread-safe, meaning it can be used concurrently.
 type Manager struct {
-	dialer *net.Dialer
+	dialer DialFunc
 
 	stopMu   sync.Mutex
 	stopConn chan struct{}
@@ -35,10 +34,16 @@ type Manager struct {
 	timeIncr  uint32
 }
 
-// NewManager creates a new UDP connection manager with the defalt dialer.
+// NewManager creates a new UDP connection manager with the default dial
+// function DialConnection.
 func NewManager() *Manager {
+	return NewManagerWithDialer(DialConnection)
+}
+
+// NewManagerWithDialer creates a UDP manager with an existing dial function.
+func NewManagerWithDialer(dialer DialFunc) *Manager {
 	return &Manager{
-		dialer:   &Dialer,
+		dialer:   dialer,
 		stopConn: make(chan struct{}),
 		connLock: make(chan struct{}, 1),
 	}
@@ -47,7 +52,7 @@ func NewManager() *Manager {
 // SetDialer sets the manager's dialer. Calling this function while the Manager
 // is working will cause a panic. Only call this method directly after
 // construction.
-func (m *Manager) SetDialer(d *net.Dialer) {
+func (m *Manager) SetDialer(d DialFunc) {
 	select {
 	case m.connLock <- struct{}{}:
 		m.dialer = d
@@ -136,7 +141,7 @@ func (m *Manager) Dial(ctx context.Context, addr string, ssrc uint32) (*Connecti
 	m.stopDial = cancel
 	m.stopMu.Unlock()
 
-	conn, err := DialConnectionCustom(ctx, m.dialer, addr, ssrc)
+	conn, err := m.dialer(ctx, addr, ssrc)
 	if err != nil {
 		// Unlock if we failed.
 		<-m.connLock