Serialize configuration updates and writes

config/user_config.go

@@ -10,9 +10,11 @@ import (
 	"os"
 	"strconv"
 	"strings"
+	"sync"
 )
 
 type Config struct {
+	mu     sync.Mutex
 	config *exportableConfig
 	fn     string
 }
@@ -49,6 +51,12 @@ type eUser struct {
 // SaveConfig atomically replaces the persisted configuration. Errors are
 // returned so an unavailable directory cannot crash the client.
 func (c *Config) SaveConfig() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.saveConfigLocked()
+}
+
+func (c *Config) saveConfigLocked() error {
 	data, err := toml.Marshal(c.config)
 	if err != nil {
 		return err
@@ -254,18 +262,24 @@ func (c *Config) findUser(address string, username string) *eUser {
 }
 
 func (c *Config) ToggleMute(u *gumble.User) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	j := c.findUser(u.GetClient().Config.Address, u.Name)
 	j.LocallyMuted = !j.LocallyMuted
 	u.SetLocallyMuted(j.LocallyMuted)
-	c.SaveConfig()
+	_ = c.saveConfigLocked()
 }
 
 func (c *Config) SetMicVolume(v float32) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	t := float32(v)
 	c.config.MicVolume = &t
 }
 
 func (c *Config) GetMicVolume() float32 {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	if c.config.MicVolume == nil {
 		return 1.0
 	}
@@ -308,6 +322,8 @@ func (c *Config) GetCertificate() *string {
 }
 
 func (c *Config) GetNoiseSuppressionEnabled() bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	if c.config.NoiseSuppressionEnabled == nil {
 		return false
 	}
@@ -315,11 +331,15 @@ func (c *Config) GetNoiseSuppressionEnabled() bool {
 }
 
 func (c *Config) SetNoiseSuppressionEnabled(enabled bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	c.config.NoiseSuppressionEnabled = &enabled
-	c.SaveConfig()
+	_ = c.saveConfigLocked()
 }
 
 func (c *Config) GetRecordingFormat() string {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	if c.config.RecordingFormat == nil {
 		return "flac"
 	}
@@ -327,6 +347,8 @@ func (c *Config) GetRecordingFormat() string {
 }
 
 func (c *Config) GetRecordingDirectory() string {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	if c.config.RecordingDirectory == nil {
 		return resolvePath("~/Audio")
 	}
@@ -334,6 +356,8 @@ func (c *Config) GetRecordingDirectory() string {
 }
 
 func (c *Config) UpdateUser(u *gumble.User) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	var j *eUser
 	var uc *gumble.Client
 	uc = u.GetClient()
@@ -349,6 +373,8 @@ func (c *Config) UpdateUser(u *gumble.User) {
 }
 
 func (c *Config) UpdateConfig(u *gumble.User) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
 	var j *eUser
 	j = c.findUser(u.GetClient().Config.Address, u.Name)
 	j.Boost = u.Boost()

config/user_config_save_test.go

@@ -2,6 +2,7 @@ package config
 
 import (
 	"path/filepath"
+	"sync"
 	"testing"
 )
 
@@ -14,3 +15,20 @@ func TestSaveConfigReturnsWriteError(t *testing.T) {
 		t.Fatal("expected configuration write error")
 	}
 }
+
+func TestConcurrentConfigurationUpdatesAndWrites(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "barnard.toml")
+	cfg := NewConfig(&path)
+	var wg sync.WaitGroup
+	for i := 0; i < 20; i++ {
+		wg.Add(1)
+		go func(enabled bool) {
+			defer wg.Done()
+			cfg.SetNoiseSuppressionEnabled(enabled)
+			if err := cfg.SaveConfig(); err != nil {
+				t.Errorf("SaveConfig: %v", err)
+			}
+		}(i%2 == 0)
+	}
+	wg.Wait()
+}