fix: add synchronization to User audio fields to prevent data races

User.AudioSource, Boost, Volume, and LocallyMuted were accessed from
both the OnAudioStream audio goroutine and the UI goroutine without
synchronization, a data race under the Go memory model.

Replace direct field access with thread-safe getter/setter methods
protected by a per-user mutex:
- SetAudioSource/GetAudioSource for the OpenAL source pointer
- SetBoost/Boost for the audio boost multiplier
- SetVolume/Volume for the volume level
- SetLocallyMuted/LocallyMuted for the local mute state

Update all call sites across config/, barnard.go, client.go,
ui_tree.go, and stream.go.

barnard.go

@@ -115,17 +115,17 @@ func (b *Barnard) TreeItemKeyPress(ui *uiterm.Ui, tree *uiterm.Tree, item uiterm
 			users := makeUsersArray(treeItem.Channel.Users)
 			for _, u := range users {
 				// Explicitly set user mute state to match channel state
-				if channelWillBeMuted && !u.LocallyMuted {
+				if channelWillBeMuted && !u.LocallyMuted() {
 					b.UserConfig.ToggleMute(u)
-				} else if !channelWillBeMuted && u.LocallyMuted {
+				} else if !channelWillBeMuted && u.LocallyMuted() {
 					b.UserConfig.ToggleMute(u)
 				}
 
-				if u.AudioSource != nil {
+				if au := u.AudioSource(); au != nil {
-					if u.LocallyMuted {
+					if u.LocallyMuted() {
-						u.AudioSource.SetGain(0)
+						au.SetGain(0)
 					} else {
-						u.AudioSource.SetGain(u.Volume)
+						au.SetGain(u.Volume())
 					}
 				}
 			}
@@ -159,11 +159,11 @@ func (b *Barnard) TreeItemKeyPress(ui *uiterm.Ui, tree *uiterm.Tree, item uiterm
 		if key == *b.Hotkeys.MuteToggle {
 			// Toggle mute for single user
 			b.UserConfig.ToggleMute(treeItem.User)
-			if treeItem.User.AudioSource != nil {
+			if au := treeItem.User.AudioSource(); au != nil {
-				if treeItem.User.LocallyMuted {
+				if treeItem.User.LocallyMuted() {
-					treeItem.User.AudioSource.SetGain(0)
+					au.SetGain(0)
 				} else {
-					treeItem.User.AudioSource.SetGain(treeItem.User.Volume)
+					au.SetGain(treeItem.User.Volume())
 				}
 			}
 			b.RebuildUserChannelTreePreservingSelection()

client.go

@@ -179,11 +179,11 @@ func (b *Barnard) OnUserChange(e *gumble.UserChangeEvent) {
 			// If the channel is muted, ensure the user is muted
 			if b.MutedChannels[e.User.Channel.ID] {
 				// Only mute if not already muted
-				if !e.User.LocallyMuted {
+				if !e.User.LocallyMuted() {
 					b.UserConfig.ToggleMute(e.User)
 				}
-				if e.User.AudioSource != nil {
+				if au := e.User.AudioSource(); au != nil {
-					e.User.AudioSource.SetGain(0)
+					au.SetGain(0)
 				}
 			}
 		}

config/user_config.go

@@ -253,7 +253,7 @@ func (c *Config) findUser(address string, username string) *eUser {
 func (c *Config) ToggleMute(u *gumble.User) {
 	j := c.findUser(u.GetClient().Config.Address, u.Name)
 	j.LocallyMuted = !j.LocallyMuted
-	u.LocallyMuted = j.LocallyMuted
+	u.SetLocallyMuted(j.LocallyMuted)
 	c.SaveConfig()
 }
 
@@ -329,11 +329,11 @@ func (c *Config) UpdateUser(u *gumble.User) {
 	uc = u.GetClient()
 	if uc != nil {
 		j = c.findUser(uc.Config.Address, u.Name)
-		u.Boost = j.Boost
+		u.SetBoost(j.Boost)
-		u.Volume = j.Volume
+		u.SetVolume(j.Volume)
-		u.LocallyMuted = j.LocallyMuted // Update LocallyMuted state from config
+		u.SetLocallyMuted(j.LocallyMuted) // Update LocallyMuted state from config
-		if u.Boost < 1 {
+		if u.Boost() < 1 {
-			u.Boost = 1
+			u.SetBoost(1)
 		}
 	}
 }
@@ -341,9 +341,9 @@ func (c *Config) UpdateUser(u *gumble.User) {
 func (c *Config) UpdateConfig(u *gumble.User) {
 	var j *eUser
 	j = c.findUser(u.GetClient().Config.Address, u.Name)
-	j.Boost = u.Boost
+	j.Boost = u.Boost()
-	j.Volume = u.Volume
+	j.Volume = u.Volume()
-	j.LocallyMuted = u.LocallyMuted // Save LocallyMuted state to config
+	j.LocallyMuted = u.LocallyMuted() // Save LocallyMuted state to config
 }
 
 func NewConfig(fn *string) *Config {

gumble/gumble/user.go

@@ -1,6 +1,8 @@
 package gumble
 
 import (
+	"sync"
+
 	"git.stormux.org/storm/barnard/gumble/go-openal/openal"
 	"git.stormux.org/storm/barnard/gumble/gumble/MumbleProto"
 	"google.golang.org/protobuf/proto"
@@ -31,9 +33,6 @@ type User struct {
 	PrioritySpeaker bool
 	// Is the user recording audio?
 	Recording bool
-	// Has the user been locally muted by the client?
-	LocallyMuted bool
-
 	// The user's comment. Contains the empty string if the user does not have a
 	// comment, or if the comment needs to be requested.
 	Comment string
@@ -58,14 +57,76 @@ type User struct {
 	audioSequence      int64
 	audioSequenceValid bool
 
-	AudioSource *openal.Source
+	// audioMu protects audio-related fields accessed from both the
-	Boost       uint16
+	// audio processing goroutine (OnAudioStream) and the UI goroutine.
-	Volume      float32
+	audioMu     sync.Mutex
+	audioSource *openal.Source
+	boost       uint16
+	volume      float32
+	locallyMuted bool
+}
+
+// SetAudioSource sets the user's OpenAL audio source (thread-safe).
+func (u *User) SetAudioSource(src *openal.Source) {
+	u.audioMu.Lock()
+	u.audioSource = src
+	u.audioMu.Unlock()
+}
+
+// AudioSource returns the user's OpenAL audio source (thread-safe).
+// The caller must not retain the pointer across unlock boundaries;
+// it is only valid while the caller ensures the source is not deleted.
+func (u *User) AudioSource() *openal.Source {
+	u.audioMu.Lock()
+	defer u.audioMu.Unlock()
+	return u.audioSource
+}
+
+// SetBoost sets the user's audio boost multiplier (thread-safe).
+func (u *User) SetBoost(b uint16) {
+	u.audioMu.Lock()
+	u.boost = b
+	u.audioMu.Unlock()
+}
+
+// Boost returns the user's audio boost multiplier (thread-safe).
+func (u *User) Boost() uint16 {
+	u.audioMu.Lock()
+	defer u.audioMu.Unlock()
+	return u.boost
+}
+
+// SetVolume sets the user's volume level (thread-safe).
+func (u *User) SetVolume(v float32) {
+	u.audioMu.Lock()
+	u.volume = v
+	u.audioMu.Unlock()
+}
+
+// Volume returns the user's volume level (thread-safe).
+func (u *User) Volume() float32 {
+	u.audioMu.Lock()
+	defer u.audioMu.Unlock()
+	return u.volume
+}
+
+// SetLocallyMuted sets whether the user is locally muted (thread-safe).
+func (u *User) SetLocallyMuted(m bool) {
+	u.audioMu.Lock()
+	u.locallyMuted = m
+	u.audioMu.Unlock()
+}
+
+// LocallyMuted returns whether the user is locally muted (thread-safe).
+func (u *User) LocallyMuted() bool {
+	u.audioMu.Lock()
+	defer u.audioMu.Unlock()
+	return u.locallyMuted
 }
 
 // IsMuted returns true if the user is muted either server-side or locally
 func (u *User) IsMuted() bool {
-	return u.Muted || u.LocallyMuted
+	return u.Muted || u.LocallyMuted()
 }
 
 func (u *User) GetClient() *Client {

gumble/gumbleopenal/stream.go

@@ -236,13 +236,13 @@ func (s *Stream) SetMicVolume(change float32, relative bool) {
 func (s *Stream) OnAudioStream(e *gumble.AudioStreamEvent) {
 	go func(e *gumble.AudioStreamEvent) {
 		var source = openal.NewSource()
-		e.User.AudioSource = &source
+		e.User.SetAudioSource(&source)
 
 		// Set initial gain based on volume and mute state
-		if e.User.LocallyMuted {
+		if e.User.LocallyMuted() {
-			e.User.AudioSource.SetGain(0)
+			source.SetGain(0)
 		} else {
-			e.User.AudioSource.SetGain(e.User.Volume)
+			source.SetGain(e.User.Volume())
 		}
 
 		bufferCount := e.Client.Config.Buffers
@@ -263,17 +263,17 @@ func (s *Stream) OnAudioStream(e *gumble.AudioStreamEvent) {
 
 		for packet := range e.C {
 			// Skip processing if user is locally muted
-			if e.User.LocallyMuted {
+			if e.User.LocallyMuted() {
 				continue
 			}
 
-			var boost uint16 = uint16(1)
 			samples := len(packet.AudioBuffer)
 			if samples > cap(raw)/2 {
 				continue
 			}
 
-			boost = e.User.Boost
+			boost := e.User.Boost()
+			userVolume := e.User.Volume()
 			recorder := s.getRecorder()
 			var recordBuffer []int16
 			recordPtr := 0
@@ -306,7 +306,7 @@ func (s *Stream) OnAudioStream(e *gumble.AudioStreamEvent) {
 						}
 					}
 					if recorder != nil {
-						recordBuffer[recordPtr] = scaleForRecording(sample, e.User.Volume)
+						recordBuffer[recordPtr] = scaleForRecording(sample, userVolume)
 						recordPtr++
 					}
 					binary.LittleEndian.PutUint16(raw[rawPtr:], uint16(sample))
@@ -325,7 +325,7 @@ func (s *Stream) OnAudioStream(e *gumble.AudioStreamEvent) {
 						}
 					}
 					if recorder != nil {
-						recordBuffer[recordPtr] = scaleForRecording(sample, e.User.Volume)
+						recordBuffer[recordPtr] = scaleForRecording(sample, userVolume)
 						recordPtr++
 					}
 					binary.LittleEndian.PutUint16(raw[rawPtr:], uint16(sample))
@@ -346,7 +346,7 @@ func (s *Stream) OnAudioStream(e *gumble.AudioStreamEvent) {
 						}
 					}
 					if recorder != nil {
-						recordSample := scaleForRecording(sample, e.User.Volume)
+						recordSample := scaleForRecording(sample, userVolume)
 						recordBuffer[recordPtr] = recordSample
 						recordBuffer[recordPtr+1] = recordSample
 						recordPtr += 2

ui_tree.go

@@ -9,12 +9,12 @@ import (
 
 func (ti TreeItem) String() string {
 	if ti.User != nil {
-		if ti.User.LocallyMuted {
+		if ti.User.LocallyMuted() {
 			return "[MUTED] " + ti.User.Name
 		}
 		// Calculate total volume as percentage
-		boostPercent := float32(ti.User.Boost-1) * 10
+		boostPercent := float32(ti.User.Boost()-1) * 10
-		totalVolume := ti.User.Volume*100 + boostPercent
+		totalVolume := ti.User.Volume()*100 + boostPercent
 		return fmt.Sprintf("%s [%.0f%%]", ti.User.Name, totalVolume)
 	}
 	if ti.Channel != nil {
@@ -35,7 +35,7 @@ func (ti TreeItem) TreeItemStyle(fg, bg uiterm.Attribute, active bool) (uiterm.A
 
 func (b *Barnard) changeVolume(users []*gumble.User, change float32) {
 	for _, u := range users {
-		au := u.AudioSource
+		au := u.AudioSource()
 		if au == nil {
 			continue
 		}
@@ -43,7 +43,7 @@ func (b *Barnard) changeVolume(users []*gumble.User, change float32) {
 		var cv float32
 		var ng float32
 		var curboost float32
-		curboost = float32((u.Boost - 1)) / 10
+		curboost = float32((u.Boost() - 1)) / 10
 		cv = au.GetGain() + curboost
 		ng = cv + change
 		boost = uint16(1)
@@ -56,9 +56,9 @@ func (b *Barnard) changeVolume(users []*gumble.User, change float32) {
 		if ng < 0 {
 			ng = 0.0
 		}
-		u.Boost = boost
+		u.SetBoost(boost)
-		u.Volume = ng
+		u.SetVolume(ng)
-		if !u.LocallyMuted {
+		if !u.LocallyMuted() {
 			au.SetGain(ng)
 		}
 		b.UserConfig.UpdateConfig(u)
@@ -68,14 +68,14 @@ func (b *Barnard) changeVolume(users []*gumble.User, change float32) {
 
 func (b *Barnard) resetVolume(users []*gumble.User) {
 	for _, u := range users {
-		au := u.AudioSource
+		au := u.AudioSource()
 		if au == nil {
 			continue
 		}
 		// Reset to original volume (1.0) and boost (1)
-		u.Boost = uint16(1)
+		u.SetBoost(uint16(1))
-		u.Volume = 1.0
+		u.SetVolume(1.0)
-		if !u.LocallyMuted {
+		if !u.LocallyMuted() {
 			au.SetGain(1.0)
 		}
 		b.UserConfig.UpdateConfig(u)