From 1bc06c7e8577ccc9f634fba9bcc90648a8dec9f3 Mon Sep 17 00:00:00 2001
From: Madelyn Olson <matolson@amazon.com>
Date: Thu, 14 May 2020 08:37:24 -0700
Subject: [PATCH] Added a refcount on timer events to prevent deletion of
 recursive timer calls

---
 src/ae.c | 10 ++++++++++
 src/ae.h |  2 ++
 2 files changed, 12 insertions(+)

diff --git a/src/ae.c b/src/ae.c
index 379cfd1e6..689a27d16 100644
--- a/src/ae.c
+++ b/src/ae.c
@@ -238,6 +238,7 @@ long long aeCreateTimeEvent(aeEventLoop *eventLoop, long long milliseconds,
     te->clientData = clientData;
     te->prev = NULL;
     te->next = eventLoop->timeEventHead;
+    te->refcount = 0;
     if (te->next)
         te->next->prev = te;
     eventLoop->timeEventHead = te;
@@ -316,6 +317,13 @@ static int processTimeEvents(aeEventLoop *eventLoop) {
         /* Remove events scheduled for deletion. */
         if (te->id == AE_DELETED_EVENT_ID) {
             aeTimeEvent *next = te->next;
+            /* If a reference exists for this timer event,
+             * don't free it. This is currently incremented
+             * for recursive timerProc calls */
+            if (te->refcount) {
+                te = next;
+                continue;
+            }
             if (te->prev)
                 te->prev->next = te->next;
             else
@@ -345,7 +353,9 @@ static int processTimeEvents(aeEventLoop *eventLoop) {
             int retval;
 
             id = te->id;
+            te->refcount++;
             retval = te->timeProc(eventLoop, id, te->clientData);
+            te->refcount--;
             processed++;
             if (retval != AE_NOMORE) {
                 aeAddMillisecondsToNow(retval,&te->when_sec,&te->when_ms);
diff --git a/src/ae.h b/src/ae.h
index 63b306615..d1b7f34bf 100644
--- a/src/ae.h
+++ b/src/ae.h
@@ -86,6 +86,8 @@ typedef struct aeTimeEvent {
     void *clientData;
     struct aeTimeEvent *prev;
     struct aeTimeEvent *next;
+    int refcount; /* refcount to prevent timer events from being
+  		   * freed in recursive time event calls. */
 } aeTimeEvent;
 
 /* A fired event */