From bedd1ded5edc3bfb6877f7025ca4b21f62492ffe Mon Sep 17 00:00:00 2001
From: Eugene Kabanov <eugene.kabanov@status.im>
Date: Fri, 5 Jun 2020 19:11:51 +0300
Subject: [PATCH] Properly fix cancellation race and not introduce FD leaks.
 (#102)

---
 chronos/asyncloop.nim         | 5 +++--
 chronos/transports/stream.nim | 6 ++----
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/chronos/asyncloop.nim b/chronos/asyncloop.nim
index 17588b3..2474b9d 100644
--- a/chronos/asyncloop.nim
+++ b/chronos/asyncloop.nim
@@ -629,8 +629,9 @@ elif unixPlatform:
     let loop = getGlobalDispatcher()
 
     proc continuation(udata: pointer) =
-      unregister(fd)
-      close(SocketHandle(fd))
+      if SocketHandle(fd) in loop.selector:
+        unregister(fd)
+        close(SocketHandle(fd))
       if not isNil(aftercb):
         aftercb(nil)
 
diff --git a/chronos/transports/stream.nim b/chronos/transports/stream.nim
index 15cd842..bc13c8d 100644
--- a/chronos/transports/stream.nim
+++ b/chronos/transports/stream.nim
@@ -722,8 +722,7 @@ when defined(windows):
         GC_unref(ovl)
 
       proc cancel(udata: pointer) {.gcsafe.} =
-        if not(retFuture.finished()):
-          sock.closeSocket()
+        sock.closeSocket()
 
       povl = RefCustomOverlapped()
       GC_ref(povl)
@@ -1251,8 +1250,7 @@ else:
         retFuture.complete(transp)
 
     proc cancel(udata: pointer) {.gcsafe.} =
-      if not(retFuture.finished()):
-        closeSocket(sock)
+      closeSocket(sock)
 
     while true:
       var res = posix.connect(SocketHandle(sock),