From 1a566d06aa966eb51caa592ff18ba6573f91046d Mon Sep 17 00:00:00 2001
From: sawka <mike.sawka@gmail.com>
Date: Thu, 9 Nov 2023 16:26:44 -0800
Subject: [PATCH] gc was collecting the lockfile early causing it not to work. 
 fixed with runtime.KeepAlive

---
 wavesrv/cmd/main-server.go   | 4 +++-
 wavesrv/pkg/scbase/scbase.go | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/wavesrv/cmd/main-server.go b/wavesrv/cmd/main-server.go
index 4fe9e595..38b9a87b 100644
--- a/wavesrv/cmd/main-server.go
+++ b/wavesrv/cmd/main-server.go
@@ -18,6 +18,7 @@ import (
 	"os/signal"
 	"path/filepath"
 	"regexp"
+	"runtime"
 	"runtime/debug"
 	"strconv"
 	"strings"
@@ -793,7 +794,7 @@ func main() {
 
 	scLock, err := scbase.AcquireWaveLock()
 	if err != nil || scLock == nil {
-		log.Printf("[error] cannot acquire wave lock: %v\n", err)
+		log.Printf("[error] cannot acquire wave lock (another instance of wavesrv is likely running): %v\n", err)
 		return
 	}
 	if len(os.Args) >= 2 && strings.HasPrefix(os.Args[1], "--migrate") {
@@ -886,4 +887,5 @@ func main() {
 	if err != nil {
 		log.Printf("ERROR: %v\n", err)
 	}
+	runtime.KeepAlive(scLock)
 }
diff --git a/wavesrv/pkg/scbase/scbase.go b/wavesrv/pkg/scbase/scbase.go
index 444bae64..c47bcb2c 100644
--- a/wavesrv/pkg/scbase/scbase.go
+++ b/wavesrv/pkg/scbase/scbase.go
@@ -156,7 +156,8 @@ func AcquireWaveLock() (*os.File, error) {
 		return nil, fmt.Errorf("cannot find/create WAVETERM_HOME directory %q", homeDir)
 	}
 	lockFileName := path.Join(homeDir, WaveLockFile)
-	fd, err := os.OpenFile(lockFileName, os.O_WRONLY|os.O_CREATE, 0600)
+	log.Printf("[base] acquiring lock on %s\n", lockFileName)
+	fd, err := os.OpenFile(lockFileName, os.O_RDWR|os.O_CREATE, 0600)
 	if err != nil {
 		return nil, err
 	}