From f094b3934bef7fb4306b805a7be44c67ea0cbd05 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=B6nke=20Ludwig?= <sludwig@rejectedsoftware.com>
Date: Sun, 11 Mar 2018 20:15:58 +0100
Subject: [PATCH] Make sure that no obsolete I/O events get processed.

Removes overlapped I/O events when a handle gets closed prematurely (before all events have been processed) to avoid potential range violation errors as a consequence.
---
 source/eventcore/drivers/winapi/core.d     | 6 ++++++
 source/eventcore/drivers/winapi/files.d    | 4 +++-
 source/eventcore/drivers/winapi/sockets.d  | 9 ++++++---
 source/eventcore/drivers/winapi/watchers.d | 1 +
 4 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/source/eventcore/drivers/winapi/core.d b/source/eventcore/drivers/winapi/core.d
index 6dac979..d426fce 100644
--- a/source/eventcore/drivers/winapi/core.d
+++ b/source/eventcore/drivers/winapi/core.d
@@ -184,6 +184,12 @@ final class WinAPIEventDriverCore : EventDriverCore {
 		nogc_assert((h in m_handles) !is null, "Handle not in use - cannot free.");
 		m_handles.remove(h);
 	}
+
+	package void discardEvents(scope OVERLAPPED_CORE*[] overlapped...)
+	{
+		import std.algorithm.searching : canFind;
+		m_ioEvents.filterPending!(evt => !overlapped.canFind(evt.overlapped));
+	}
 }
 
 private long currStdTime()
diff --git a/source/eventcore/drivers/winapi/files.d b/source/eventcore/drivers/winapi/files.d
index af63e27..3297989 100644
--- a/source/eventcore/drivers/winapi/files.d
+++ b/source/eventcore/drivers/winapi/files.d
@@ -146,8 +146,10 @@ final class WinAPIEventDriverFiles : EventDriverFiles {
 	override bool releaseRef(FileFD descriptor)
 	{
 		auto h = idToHandle(descriptor);
-		return m_core.m_handles[h].releaseRef({
+		auto slot = &m_core.m_handles[h];
+		return slot.releaseRef({
 			close(descriptor);
+			m_core.discardEvents(&slot.file.read.overlapped, &slot.file.write.overlapped);
 			m_core.freeSlot(h);
 		});
 	}
diff --git a/source/eventcore/drivers/winapi/sockets.d b/source/eventcore/drivers/winapi/sockets.d
index 8e5eba3..4d9b9b4 100644
--- a/source/eventcore/drivers/winapi/sockets.d
+++ b/source/eventcore/drivers/winapi/sockets.d
@@ -697,13 +697,15 @@ final class WinAPIEventDriverSockets : EventDriverSockets {
 	override bool releaseRef(SocketFD fd)
 	{
 		import taggedalgebraic : hasType;
-		nogc_assert(m_sockets[fd].common.refCount > 0, "Releasing reference to unreferenced socket FD.");
-		if (--m_sockets[fd].common.refCount == 0) {
-			final switch (m_sockets[fd].specific.kind) with (SocketVector.FieldType) {
+		auto slot = () @trusted { return &m_sockets[fd]; } ();
+		nogc_assert(slot.common.refCount > 0, "Releasing reference to unreferenced socket FD.");
+		if (--slot.common.refCount == 0) {
+			final switch (slot.specific.kind) with (SocketVector.FieldType) {
 				case Kind.none: break;
 				case Kind.streamSocket:
 					cancelRead(cast(StreamSocketFD)fd);
 					cancelWrite(cast(StreamSocketFD)fd);
+					m_core.discardEvents(&slot.streamSocket.read.overlapped, &slot.streamSocket.write.overlapped);
 					break;
 				case Kind.streamListen:
 					if (m_sockets[fd].streamListen.acceptCallback)
@@ -712,6 +714,7 @@ final class WinAPIEventDriverSockets : EventDriverSockets {
 				case Kind.datagramSocket:
 					cancelReceive(cast(DatagramSocketFD)fd);
 					cancelSend(cast(DatagramSocketFD)fd);
+					m_core.discardEvents(&slot.datagramSocket.read.overlapped, &slot.datagramSocket.write.overlapped);
 					break;
 			}
 
diff --git a/source/eventcore/drivers/winapi/watchers.d b/source/eventcore/drivers/winapi/watchers.d
index 524af9d..9606148 100644
--- a/source/eventcore/drivers/winapi/watchers.d
+++ b/source/eventcore/drivers/winapi/watchers.d
@@ -82,6 +82,7 @@ final class WinAPIEventDriverWatchers : EventDriverWatchers {
 					catch (Exception e) assert(false, "Freeing directory watcher buffer failed.");
 				} ();
 				slot.watcher.buffer = null;
+				core.discardEvents(&slot.watcher.overlapped, &slot.file.write.overlapped);
 				core.freeSlot(handle);
 			}))
 		{