From 92b645f34cbab28dbfd32699d40afe8b665706cd Mon Sep 17 00:00:00 2001
From: Sasha Koshka <supergriffin64@gmail.com>
Date: Wed, 31 May 2023 18:49:00 -0400
Subject: [PATCH] Routine manager now recovers from panicking goroutines

---
 routines/routines.go | 42 +++++++++++++++++++++++++++---------------
 1 file changed, 27 insertions(+), 15 deletions(-)

diff --git a/routines/routines.go b/routines/routines.go
index f727bb2..9d9431a 100644
--- a/routines/routines.go
+++ b/routines/routines.go
@@ -6,6 +6,7 @@ import "fmt"
 import "log"
 import "time"
 import "sync"
+import "errors"
 
 type routine struct {
 	run, shutdown func () error
@@ -71,17 +72,16 @@ type Manager struct {
 // Run returns  only when all routines have exited.
 func (manager *Manager) Run () error {
 	var waitGroup sync.WaitGroup
-	var errExit   error
 	
 	for _, routine := range manager.Routines {
 		if routine != nil {
 			waitGroup.Add(1)
-			go manager.runRoutine(routine, &waitGroup, &errExit)
+			go manager.runRoutine(routine, &waitGroup)
 		}
 	}
 	
 	waitGroup.Wait()
-	return errExit
+	return nil
 }
 
 // Shutdown shuts down all routines in the manager.
@@ -113,21 +113,26 @@ func (manager *Manager) log (message ...any) {
 	}
 }
 
-func (manager *Manager) runRoutine (routine Routine, group *sync.WaitGroup, errExit *error) {
+func (manager *Manager) runRoutine (routine Routine, group *sync.WaitGroup) {
 	defer group.Done()
 
-	var err error
 	for {
+		lastStart := time.Now()
+		err := panicWrap(routine.Run)
+
 		stopping := false
 		manager.stoppingMutex.Lock()
 		stopping = manager.stopping
 		manager.stoppingMutex.Unlock()
-		if stopping { break }
-	
-		// TODO: recover from panics
-		lastStart := time.Now()
-		err = routine.Run()
-
+		if stopping {
+			if err == nil {
+				manager.log("(i) stopped routine")
+			} else {
+				manager.log("!!! stopped routine, with error:", err)
+			}
+			break
+		}
+		
 		if err == nil {
 			manager.log("(i) routine exited")
 			break
@@ -142,8 +147,15 @@ func (manager *Manager) runRoutine (routine Routine, group *sync.WaitGroup, errE
 			manager.log("(i) routine is being restarted")
 		}
 	}
-	
-	if err != nil {
-		*errExit = err
-	}
+}
+
+func panicWrap (f func () error) (err error) {
+	defer func () {
+		if pan := recover(); pan != nil {
+			err = errors.New(fmt.Sprint(pan))
+		}
+	} ()
+	
+	err = f()
+	return
 }