From d92b5eebccd0f63083e0cd89431d2d3b6e335074 Mon Sep 17 00:00:00 2001
From: Ilya Fedin <fedin-ilja2010@ya.ru>
Date: Wed, 3 Jun 2020 07:49:46 +0400
Subject: [PATCH] Restore X error handler just like qgtk3

---
 Telegram/SourceFiles/platform/linux/linux_libs.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Telegram/SourceFiles/platform/linux/linux_libs.cpp b/Telegram/SourceFiles/platform/linux/linux_libs.cpp
index ac897ea0d1..21364c92c5 100644
--- a/Telegram/SourceFiles/platform/linux/linux_libs.cpp
+++ b/Telegram/SourceFiles/platform/linux/linux_libs.cpp
@@ -11,6 +11,10 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "platform/linux/linux_desktop_environment.h"
 #include "platform/linux/specific_linux.h"
 
+extern "C" {
+#include <X11/Xlib.h>
+}
+
 #include <QtGui/QGuiApplication>
 
 namespace Platform {
@@ -150,6 +154,10 @@ bool setupGtkBase(QLibrary &lib_gtk) {
 		}
 	}
 
+	// gtk_init will reset the Xlib error handler, and that causes
+	// Qt applications to quit on X errors. Therefore, we need to manually restore it.
+	int (*oldErrorHandler)(Display *, XErrorEvent *) = XSetErrorHandler(nullptr);
+
 	DEBUG_LOG(("Library gtk functions loaded!"));
 	if (!gtk_init_check(0, 0)) {
 		gtk_init_check = nullptr;
@@ -158,6 +166,8 @@ bool setupGtkBase(QLibrary &lib_gtk) {
 	}
 	DEBUG_LOG(("Checked gtk with gtk_init_check!"));
 
+	XSetErrorHandler(oldErrorHandler);
+
 	// Use our custom log handler.
 	g_log_set_handler("Gtk", G_LOG_LEVEL_MESSAGE, gtkMessageHandler, nullptr);