From 2390b19706dcc37e6155c964b3d5b850fef0fa0e Mon Sep 17 00:00:00 2001
From: Don HO <don.h@free.fr>
Date: Wed, 27 Dec 2017 14:55:35 +0100
Subject: [PATCH] Fix a crash bug due to eventual disordered notifications sent
 to plugins

The Access Violation while closing Notepad++:
https://github.com/notepad-plus-plus/notepad-plus-plus/issues/3961
could be due to SCN_UPDATEUI sending after NPPN_SHUTDOWN, that makes
plugins treat SCN_UPDATEUI on the released handle.

To avoid such situation, once NPPN_SHUTDOWN has been sent, no more
message will be sent to plugin.

Fixes #3961, fixes #4021
---
 PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp | 4 ++++
 PowerEditor/src/MISC/PluginsManager/PluginsManager.h   | 1 +
 2 files changed, 5 insertions(+)

diff --git a/PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp b/PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp
index 5cfb363de..f94371e07 100644
--- a/PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp
+++ b/PowerEditor/src/MISC/PluginsManager/PluginsManager.cpp
@@ -564,6 +564,10 @@ void PluginsManager::runPluginCommand(const TCHAR *pluginName, int commandID)
 
 void PluginsManager::notify(const SCNotification *notification)
 {
+	if (_noMoreNotification) // this boolean should be enabled after NPPN_SHUTDOWN has been sent
+		return;
+	_noMoreNotification = notification->nmhdr.code == NPPN_SHUTDOWN;
+
 	for (size_t i = 0, len = _pluginInfos.size() ; i < len ; ++i)
 	{
         if (_pluginInfos[i]->_hLib)
diff --git a/PowerEditor/src/MISC/PluginsManager/PluginsManager.h b/PowerEditor/src/MISC/PluginsManager/PluginsManager.h
index 28d9832d4..b2c48fdf2 100644
--- a/PowerEditor/src/MISC/PluginsManager/PluginsManager.h
+++ b/PowerEditor/src/MISC/PluginsManager/PluginsManager.h
@@ -137,6 +137,7 @@ private:
 	bool _isDisabled = false;
 	IDAllocator _dynamicIDAlloc;
 	IDAllocator _markerAlloc;
+	bool _noMoreNotification = false;
 
 	void pluginCrashAlert(const TCHAR *pluginName, const TCHAR *funcSignature)
 	{