fix randomizer and err in config

client/identity.go

@@ -6,6 +6,8 @@ import (
 	"math/rand"
 	"os"
 	"path/filepath"
+	"strings"
+	"sync"
 	"time"
 
 	"forge.redroom.link/yves/meowlib"
@@ -15,6 +17,12 @@ import (
 
 const maxHiddenCount = 30
 
+// Package-level random number generator with mutex for thread-safe access
+var (
+	rngMu sync.Mutex
+	rng   = rand.New(rand.NewSource(time.Now().UnixNano()))
+)
+
 type Identity struct {
 	Nickname             string           `json:"nickname,omitempty"`
 	DefaultAvatar        string           `json:"default_avatar,omitempty"`
@@ -282,8 +290,9 @@ func (id *Identity) HidePeer(peerIdx int, password string) error {
 
 func (id *Identity) generateRandomHiddenStuff() error {
 	var err error
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-	count := r.Intn(maxHiddenCount) + 1
+	rngMu.Lock()
+	count := rng.Intn(maxHiddenCount) + 1
+	rngMu.Unlock()
 	for i := 1; i < count; i++ {
 		var p Peer
 		p.Uid = uuid.New().String()
@@ -385,17 +394,29 @@ func (id *Identity) SaveBackgroundJob() error {
 }
 
 func randomLenString(min int, max int) string {
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-	n := r.Intn(max-min) + min
-	return randomString(n)
+	rngMu.Lock()
+	defer rngMu.Unlock()
+
+	length := rng.Intn(max-min+1) + min
+	return randomStringLocked(length)
 }
 
 func randomString(n int) string {
-	r := rand.New(rand.NewSource(time.Now().UnixNano()))
-	var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
-	s := make([]rune, n)
-	for i := range s {
-		s[i] = letters[r.Intn(len(letters))]
-	}
-	return string(s)
+	rngMu.Lock()
+	defer rngMu.Unlock()
+
+	return randomStringLocked(n)
+}
+
+// randomStringLocked generates a random string of length n.
+// Must be called with rngMu already locked.
+func randomStringLocked(n int) string {
+	const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+
+	var b strings.Builder
+	b.Grow(n)
+	for i := 0; i < n; i++ {
+		b.WriteByte(letterBytes[rng.Intn(len(letterBytes))])
+	}
+	return b.String()
 }