[NOD-696] Handle panics on time.AfterFunc (#600)

* [NOD-696] Handle panics on time.AfterFunc

* [NOD-696] Fix comment

* [NOD-696] Rename afterFunc->spawnAfter

connmgr/connmanager.go

@@ -232,9 +232,9 @@ func (cm *ConnManager) handleFailedConn(c *ConnReq, err error) {
 		if shouldWriteLog {
 			log.Debugf("Retrying further connections to %s every %s", c, d)
 		}
-		time.AfterFunc(d, func() {
+		spawnAfter(d, func() {
 			cm.Connect(c)
-		})
+		}, nil)
 	} else if cm.cfg.GetNewAddress != nil {
 		cm.failedAttempts++
 		if cm.failedAttempts >= maxFailedAttempts {
@@ -243,9 +243,7 @@ func (cm *ConnManager) handleFailedConn(c *ConnReq, err error) {
 					"-- retrying further connections every %s", maxFailedAttempts,
 					cm.cfg.RetryDuration)
 			}
-			time.AfterFunc(cm.cfg.RetryDuration, func() {
+			spawnAfter(cm.cfg.RetryDuration, cm.NewConnReq, cm.handlePanic)
-				cm.NewConnReq()
-			})
 		} else {
 			spawn(cm.NewConnReq, cm.handlePanic)
 		}

connmgr/log.go

@@ -11,3 +11,4 @@ import (
 
 var log, _ = logger.Get(logger.SubsystemTags.CMGR)
 var spawn = panics.GoroutineWrapperFuncWithPanicHandler(log)
+var spawnAfter = panics.AfterFuncWrapperFuncWithPanicHandler(log)

peer/log.go

@@ -23,6 +23,7 @@ const (
 
 var log, _ = logger.Get(logger.SubsystemTags.PEER)
 var spawn = panics.GoroutineWrapperFunc(log)
+var spawnAfter = panics.AfterFuncWrapperFunc(log)
 
 // formatLockTime returns a transaction lock time as a human-readable string.
 func formatLockTime(lockTime uint64) string {

peer/peer.go

@@ -1346,7 +1346,7 @@ cleanup:
 func (p *Peer) inHandler() {
 	// The timer is stopped when a new message is received and reset after it
 	// is processed.
-	idleTimer := time.AfterFunc(idleTimeout, func() {
+	idleTimer := spawnAfter(idleTimeout, func() {
 		log.Warnf("Peer %s no answer for %s -- disconnecting", p, idleTimeout)
 		p.Disconnect()
 	})

util/panics/panics.go

@@ -4,6 +4,7 @@ import (
 	"github.com/kaspanet/kaspad/logs"
 	"github.com/kaspanet/kaspad/signal"
 	"runtime/debug"
+	"time"
 )
 
 // HandlePanic recovers panics, log them, runs an optional panicHandler,
@@ -22,7 +23,7 @@ func HandlePanic(log logs.Logger, goroutineStackTrace []byte, panicHandler func(
 	}
 }
 
-// GoroutineWrapperFunc returns a goroutine wrapper function that handles panics and write them to the log.
+// GoroutineWrapperFunc returns a goroutine wrapper function that handles panics and writes them to the log.
 func GoroutineWrapperFunc(log logs.Logger) func(func()) {
 	return func(f func()) {
 		stackTrace := debug.Stack()
@@ -34,7 +35,7 @@ func GoroutineWrapperFunc(log logs.Logger) func(func()) {
 }
 
 // GoroutineWrapperFuncWithPanicHandler returns a goroutine wrapper function that handles panics,
-// write them to the log, and executes a handler function for panics.
+// writes them to the log, and executes a handler function for panics.
 func GoroutineWrapperFuncWithPanicHandler(log logs.Logger) func(func(), func()) {
 	return func(f func(), panicHandler func()) {
 		stackTrace := debug.Stack()
@@ -44,3 +45,26 @@ func GoroutineWrapperFuncWithPanicHandler(log logs.Logger) func(func(), func())
 		}()
 	}
 }
+
+// AfterFuncWrapperFunc returns a time.AfterFunc wrapper function that handles panics.
+func AfterFuncWrapperFunc(log logs.Logger) func(d time.Duration, f func()) *time.Timer {
+	return func(d time.Duration, f func()) *time.Timer {
+		stackTrace := debug.Stack()
+		return time.AfterFunc(d, func() {
+			defer HandlePanic(log, stackTrace, nil)
+			f()
+		})
+	}
+}
+
+// AfterFuncWrapperFuncWithPanicHandler returns a time.AfterFunc wrapper function that handles panics,
+// writes them to the log, and executes a handler function for panics.
+func AfterFuncWrapperFuncWithPanicHandler(log logs.Logger) func(d time.Duration, f func(), panicHandler func()) *time.Timer {
+	return func(d time.Duration, f func(), panicHandler func()) *time.Timer {
+		stackTrace := debug.Stack()
+		return time.AfterFunc(d, func() {
+			defer HandlePanic(log, stackTrace, panicHandler)
+			f()
+		})
+	}
+}