From b59e759e87d15598fe3c8e455c029d4726860725 Mon Sep 17 00:00:00 2001
From: cheatfate <eugene.kabanov@status.im>
Date: Wed, 23 Oct 2019 14:13:23 +0300
Subject: [PATCH] Fix #53

---
 chronos/transports/common.nim | 6 ++++++
 chronos/transports/stream.nim | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/chronos/transports/common.nim b/chronos/transports/common.nim
index 78cae403..f8fb55ff 100644
--- a/chronos/transports/common.nim
+++ b/chronos/transports/common.nim
@@ -457,6 +457,12 @@ template checkClosed*(t: untyped, future: untyped) =
     future.fail(newException(TransportError, "Transport is already closed!"))
     return future
 
+template checkWriteEof*(t: untyped, future: untyped) =
+  if (WriteEof in (t).state):
+    future.fail(newException(TransportError,
+                             "Transport connection is already dropped!"))
+    return future
+
 template getError*(t: untyped): ref Exception =
   var err = (t).error
   (t).error = nil
diff --git a/chronos/transports/stream.nim b/chronos/transports/stream.nim
index 604bb924..3348d0f2 100644
--- a/chronos/transports/stream.nim
+++ b/chronos/transports/stream.nim
@@ -1614,6 +1614,7 @@ proc write*(transp: StreamTransport, pbytes: pointer,
   ## ``transp``.
   var retFuture = newFuture[int]("stream.transport.write(pointer)")
   transp.checkClosed(retFuture)
+  transp.checkWriteEof(retFuture)
   var vector = StreamVector(kind: DataBuffer, writer: retFuture,
                             buf: pbytes, buflen: nbytes)
   transp.queue.addLast(vector)
@@ -1625,6 +1626,7 @@ proc write*(transp: StreamTransport, msg: string, msglen = -1): Future[int] =
   ## Write data from string ``msg`` using transport ``transp``.
   var retFuture = newFutureStr[int]("stream.transport.write(string)")
   transp.checkClosed(retFuture)
+  transp.checkWriteEof(retFuture)
   if not isLiteral(msg):
     shallowCopy(retFuture.gcholder, msg)
   else:
@@ -1642,6 +1644,7 @@ proc write*[T](transp: StreamTransport, msg: seq[T], msglen = -1): Future[int] =
   ## Write sequence ``msg`` using transport ``transp``.
   var retFuture = newFutureSeq[int, T]("stream.transport.write(seq)")
   transp.checkClosed(retFuture)
+  transp.checkWriteEof(retFuture)
   if not isLiteral(msg):
     shallowCopy(retFuture.gcholder, msg)
   else:
@@ -1667,6 +1670,7 @@ proc writeFile*(transp: StreamTransport, handle: int,
       raise newException(TransportNoSupport, "writeFile() is not supported!")
   var retFuture = newFuture[int]("stream.transport.writeFile")
   transp.checkClosed(retFuture)
+  transp.checkWriteEof(retFuture)
   var vector = StreamVector(kind: DataFile, writer: retFuture,
                             buf: cast[pointer](size), offset: offset,
                             buflen: handle)