Fix misunderstanding of wxDialog lifetime handling.2978-wxptr-crash

Broken by d0308d53dd9f4d036d8c5fe8023920fcdfd43f39

wxDialog can be stack allocated if opened with ShowModal(), but not with
Show().  Go back to wx_ptr for those that are opened with Show().

1 files changed, 117 insertions, 0 deletions

diff --git a/src/wx/wx_ptr.h b/src/wx/wx_ptr.h
new file mode 100644
index 000000000..fcca8b18b
--- /dev/null
+++ b/src/wx/wx_ptr.h
@@ -0,0 +1,117 @@
+/*
+    Copyright (C) 2023 Carl Hetherington <cth@carlh.net>
+
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    DCP-o-matic is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
+
+*/
+
+
+#ifndef DCPOMATIC_WX_PTR_H
+#define DCPOMATIC_WX_PTR_H
+
+
+#include "lib/dcpomatic_assert.h"
+#include <utility>
+
+
+template <class T>
+class wx_ptr
+{
+public:
+	wx_ptr() {}
+
+	explicit wx_ptr(T* wx)
+		: _wx(wx)
+	{}
+
+	wx_ptr(wx_ptr&) = delete;
+	wx_ptr& operator=(wx_ptr&) = delete;
+
+	wx_ptr(wx_ptr&& other)
+	{
+		_wx = other._wx;
+		other._wx = nullptr;
+	}
+
+	wx_ptr& operator=(wx_ptr&& other)
+	{
+		if (this != &other) {
+			_wx = other._wx;
+			other._wx = nullptr;
+		}
+		return *this;
+	}
+
+	~wx_ptr()
+	{
+		if (_wx) {
+			_wx->Destroy();
+		}
+	}
+
+	wx_ptr& operator=(T* ptr)
+	{
+		if (_wx) {
+			_wx->Destroy();
+		}
+		_wx = ptr;
+		return *this;
+	}
+
+	T* operator->()
+	{
+		DCPOMATIC_ASSERT(_wx);
+		return _wx;
+	}
+
+	operator bool() const
+	{
+		return _wx != nullptr;
+	}
+
+	void reset()
+	{
+		if (_wx) {
+			_wx->Destroy();
+			_wx = nullptr;
+		}
+	}
+
+	template <typename... Args>
+	void reset(Args&&... args)
+	{
+		if (_wx) {
+			_wx->Destroy();
+			_wx = nullptr;
+		}
+		_wx = new T(std::forward<Args>(args)...);
+	}
+
+private:
+	T* _wx = nullptr;
+};
+
+
+
+template <class T, typename... Args>
+wx_ptr<T>
+make_wx(Args... args)
+{
+	return wx_ptr<T>(new T(std::forward<Args>(args)...));
+}
+
+
+#endif