From 1841b88d6cda425b7a4126eb8ff4fcf564c783d0 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 12 Aug 2021 13:07:16 +0300
Subject: [PATCH] Threadsafe logging to file descriptor

---
 src/log.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/log.go b/src/log.go
index 78f9acc..a2e72b2 100644
--- a/src/log.go
+++ b/src/log.go
@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"fmt"
 	"os"
+	"sync"
 	"time"
 
 	"go.cypherpunks.ru/recfile"
@@ -29,7 +30,10 @@ import (
 
 const LogFdPrefix = "FD:"
 
-var LogFd *os.File
+var (
+	LogFd     *os.File
+	LogFdLock sync.Mutex
+)
 
 type LE struct {
 	K string
@@ -69,7 +73,9 @@ func (les LEs) Rec() string {
 
 func (ctx *Ctx) Log(rec string) {
 	if LogFd != nil {
+		LogFdLock.Lock()
 		LogFd.WriteString(rec)
+		LogFdLock.Unlock()
 		return
 	}
 	fdLock, err := os.OpenFile(
-- 
2.44.0