From bc82d48124c26c8192eb8bbb53abf35839a390c0 Mon Sep 17 00:00:00 2001
From: sawka <mike@commandline.dev>
Date: Mon, 27 Jan 2025 18:00:05 -0800
Subject: [PATCH] send SIGUSR1 to dump all goroutines (for debugging)

---
 cmd/server/main-server.go | 18 ++++++++++++++++++
 pkg/util/utilfn/utilfn.go |  7 +++++++
 2 files changed, 25 insertions(+)

diff --git a/cmd/server/main-server.go b/cmd/server/main-server.go
index 06ce5639d8..4cfe5c76b4 100644
--- a/cmd/server/main-server.go
+++ b/cmd/server/main-server.go
@@ -25,6 +25,7 @@ import (
 	"github.com/wavetermdev/waveterm/pkg/service"
 	"github.com/wavetermdev/waveterm/pkg/telemetry"
 	"github.com/wavetermdev/waveterm/pkg/util/shellutil"
+	"github.com/wavetermdev/waveterm/pkg/util/utilfn"
 	"github.com/wavetermdev/waveterm/pkg/wavebase"
 	"github.com/wavetermdev/waveterm/pkg/waveobj"
 	"github.com/wavetermdev/waveterm/pkg/wcloud"
@@ -75,6 +76,9 @@ func installShutdownSignalHandlers() {
 	sigCh := make(chan os.Signal, 1)
 	signal.Notify(sigCh, syscall.SIGHUP, syscall.SIGTERM, syscall.SIGINT)
 	go func() {
+		defer func() {
+			panichandler.PanicHandler("installShutdownSignalHandlers", recover())
+		}()
 		for sig := range sigCh {
 			doShutdown(fmt.Sprintf("got signal %v", sig))
 			break
@@ -82,6 +86,19 @@ func installShutdownSignalHandlers() {
 	}()
 }
 
+func installSIGUSR1Handler() {
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, syscall.SIGUSR1)
+	go func() {
+		defer func() {
+			panichandler.PanicHandler("installSIGUSR1Handler", recover())
+		}()
+		for range sigCh {
+			utilfn.DumpGoRoutineStacks()
+		}
+	}()
+}
+
 // watch stdin, kill server if stdin is closed
 func stdinReadWatch() {
 	buf := make([]byte, 1024)
@@ -296,6 +313,7 @@ func main() {
 
 	createMainWshClient()
 	installShutdownSignalHandlers()
+	installSIGUSR1Handler()
 	startupActivityUpdate()
 	go stdinReadWatch()
 	go telemetryLoop()
diff --git a/pkg/util/utilfn/utilfn.go b/pkg/util/utilfn/utilfn.go
index 36cd4be169..fb04dd61c8 100644
--- a/pkg/util/utilfn/utilfn.go
+++ b/pkg/util/utilfn/utilfn.go
@@ -20,6 +20,7 @@ import (
 	"os/exec"
 	"reflect"
 	"regexp"
+	"runtime"
 	"sort"
 	"strconv"
 	"strings"
@@ -941,3 +942,9 @@ func HasBinaryData(data []byte) bool {
 	}
 	return false
 }
+
+func DumpGoRoutineStacks() {
+	buf := make([]byte, 1<<20)
+	n := runtime.Stack(buf, true)
+	os.Stdout.Write(buf[:n])
+}