From 293f82daa07bbc357940e5dd214f7c534bab0a86 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Tue, 25 Apr 2023 11:03:54 +0200
Subject: [PATCH] Don't use wx_ptr for the splash screen.

Using wx_ptr in the wxApp object seems bad because in ~App wxWidgets
deletes all top-level windows in `DeleteAllTLWs` so if ~wx_ptr then
tries to destroy them we get a use-after-free.
---
 src/tools/dcpomatic.cc        | 9 +++++----
 src/tools/dcpomatic_editor.cc | 2 +-
 src/tools/dcpomatic_kdm.cc    | 2 +-
 src/tools/dcpomatic_player.cc | 2 +-
 src/wx/wx_util.cc             | 8 ++++----
 src/wx/wx_util.h              | 2 +-
 6 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/tools/dcpomatic.cc b/src/tools/dcpomatic.cc
index a7b3af8bc..3d944e780 100644
--- a/src/tools/dcpomatic.cc
+++ b/src/tools/dcpomatic.cc
@@ -1709,7 +1709,7 @@ private:
 		}
 		catch (exception& e)
 		{
-			_splash.reset();
+			close_splash();
 			error_dialog (nullptr, wxString::Format ("DCP-o-matic could not start."), std_to_wx(e.what()));
 		}
 
@@ -1821,7 +1821,8 @@ private:
 
 	void close_splash ()
 	{
-		_splash.reset();
+		_splash->Destroy();
+		_splash = nullptr;
 	}
 
 	void config_failed_to_load (Config::LoadFailure what)
@@ -1839,7 +1840,7 @@ private:
 		/* Destroy the splash screen here, as otherwise bad things seem to happen (for reasons unknown)
 		   when we open our recreate dialog, close it, *then* try to Destroy the splash (the Destroy fails).
 		*/
-		_splash.reset();
+		close_splash();
 
 		auto config = Config::instance();
 		switch (reason) {
@@ -1908,7 +1909,7 @@ private:
 	}
 
 	DOMFrame* _frame = nullptr;
-	wx_ptr<wxSplashScreen> _splash;
+	wxSplashScreen* _splash;
 	shared_ptr<wxTimer> _timer;
 	string _film_to_load;
 	string _film_to_create;
diff --git a/src/tools/dcpomatic_editor.cc b/src/tools/dcpomatic_editor.cc
index 663eb8e3b..a61a17ce4 100644
--- a/src/tools/dcpomatic_editor.cc
+++ b/src/tools/dcpomatic_editor.cc
@@ -428,7 +428,7 @@ private:
 
 	bool OnInit () override
 	{
-		wx_ptr<wxSplashScreen> splash;
+		wxSplashScreen* splash;
 		try {
 			wxInitAllImageHandlers ();
 
diff --git a/src/tools/dcpomatic_kdm.cc b/src/tools/dcpomatic_kdm.cc
index 2e28b548a..e2993f9f2 100644
--- a/src/tools/dcpomatic_kdm.cc
+++ b/src/tools/dcpomatic_kdm.cc
@@ -798,7 +798,7 @@ private:
 
 	bool OnInit () override
 	{
-		wx_ptr<wxSplashScreen> splash;
+		wxSplashScreen* splash;
 
 		try {
 			wxInitAllImageHandlers ();
diff --git a/src/tools/dcpomatic_player.cc b/src/tools/dcpomatic_player.cc
index 5ce02b1ea..ab018c44b 100644
--- a/src/tools/dcpomatic_player.cc
+++ b/src/tools/dcpomatic_player.cc
@@ -1171,7 +1171,7 @@ private:
 
 	bool OnInit () override
 	{
-		wx_ptr<wxSplashScreen> splash;
+		wxSplashScreen* splash;
 		try {
 			wxInitAllImageHandlers ();
 
diff --git a/src/wx/wx_util.cc b/src/wx/wx_util.cc
index 7a41f66e7..f36bcdf25 100644
--- a/src/wx/wx_util.cc
+++ b/src/wx/wx_util.cc
@@ -537,10 +537,10 @@ setup_audio_channels_choice (wxChoice* choice, int minimum)
 }
 
 
-wx_ptr<wxSplashScreen>
+wxSplashScreen*
 maybe_show_splash ()
 {
-	wx_ptr<wxSplashScreen> splash;
+	wxSplashScreen* splash;
 
 	try {
 		wxBitmap bitmap;
@@ -555,9 +555,9 @@ maybe_show_splash ()
 			}
 #ifdef DCPOMATIC_WINDOWS
 			/* Having wxSTAY_ON_TOP means error dialogues hide behind the splash screen on Windows, no matter what I try */
-			splash.reset(bitmap, wxSPLASH_CENTRE_ON_SCREEN | wxSPLASH_NO_TIMEOUT, 0, nullptr, -1, wxDefaultPosition, wxDefaultSize, wxBORDER_SIMPLE | wxFRAME_NO_TASKBAR);
+			splash = new wxSplashScreen(bitmap, wxSPLASH_CENTRE_ON_SCREEN | wxSPLASH_NO_TIMEOUT, 0, nullptr, -1, wxDefaultPosition, wxDefaultSize, wxBORDER_SIMPLE | wxFRAME_NO_TASKBAR);
 #else
-			splash.reset(bitmap, wxSPLASH_CENTRE_ON_SCREEN | wxSPLASH_NO_TIMEOUT, 0, nullptr, -1);
+			splash = new wxSplashScreen(bitmap, wxSPLASH_CENTRE_ON_SCREEN | wxSPLASH_NO_TIMEOUT, 0, nullptr, -1);
 #endif
 			wxYield ();
 		}
diff --git a/src/wx/wx_util.h b/src/wx/wx_util.h
index e18cfc5a7..66b01640c 100644
--- a/src/wx/wx_util.h
+++ b/src/wx/wx_util.h
@@ -119,7 +119,7 @@ extern wxString context_translation (wxString);
 extern std::string string_client_data (wxClientData* o);
 extern wxString time_to_timecode (dcpomatic::DCPTime t, double fps);
 extern void setup_audio_channels_choice (wxChoice* choice, int minimum);
-extern wx_ptr<wxSplashScreen> maybe_show_splash();
+extern wxSplashScreen* maybe_show_splash();
 extern double calculate_mark_interval (double start);
 extern bool display_progress (wxString title, wxString task);
 extern bool report_errors_from_last_job (wxWindow* parent);
-- 
2.30.2