Merge pull request sirupsen#1234 from sirupsen/dbd-cleanup

fix race condition AddHook and traces

entry.go

@@ -261,7 +261,15 @@ func (entry *Entry) log(level Level, msg string) {
 }
 
 func (entry *Entry) fireHooks() {
-	err := entry.Logger.Hooks.Fire(entry.Level, entry)
+	var tmpHooks LevelHooks
+	entry.Logger.mu.Lock()
+	tmpHooks = make(LevelHooks, len(entry.Logger.Hooks))
+	for k, v := range entry.Logger.Hooks {
+		tmpHooks[k] = v
+	}
+	entry.Logger.mu.Unlock()
+
+	err := tmpHooks.Fire(entry.Level, entry)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "Failed to fire hook: %v\n", err)
 	}

hook_test.go

@@ -3,13 +3,15 @@ package logrus_test
 import (
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"sync"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
 	. "github.com/sirupsen/logrus"
+	"github.com/sirupsen/logrus/hooks/test"
 	. "github.com/sirupsen/logrus/internal/testutils"
 )
 
@@ -191,6 +193,20 @@ func TestAddHookRace(t *testing.T) {
 	})
 }
 
+func TestAddHookRace2(t *testing.T) {
+	t.Parallel()
+
+	for i := 0; i < 3; i++ {
+		testname := fmt.Sprintf("Test %d", i)
+		t.Run(testname, func(t *testing.T) {
+			t.Parallel()
+
+			_ = test.NewGlobal()
+			Info(testname)
+		})
+	}
+}
+
 type HookCallFunc struct {
 	F func()
 }