From 1f1661f36ffd7a5662847f0642c7a7ebdcadc0f0 Mon Sep 17 00:00:00 2001
From: Carl Hetherington <cth@carlh.net>
Date: Thu, 27 Sep 2018 15:26:05 +0100
Subject: [PATCH] Disable preferences menu if the config can't be written.

---
 src/lib/config.cc             | 12 ++++++++++++
 src/lib/config.h              |  1 +
 src/tools/dcpomatic_player.cc | 28 ++++++++++++++++++++++------
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/src/lib/config.cc b/src/lib/config.cc
index d7fd74449..e1d5b958d 100644
--- a/src/lib/config.cc
+++ b/src/lib/config.cc
@@ -1201,3 +1201,15 @@ Config::copy_and_link (boost::filesystem::path new_file) const
 	boost::filesystem::copy_file (config_file(), new_file, boost::filesystem::copy_option::overwrite_if_exists);
 	link (new_file);
 }
+
+bool
+Config::have_write_permission () const
+{
+	FILE* f = fopen_boost (config_file(), "r+");
+	if (!f) {
+		return false;
+	}
+
+	fclose (f);
+	return true;
+}
diff --git a/src/lib/config.h b/src/lib/config.h
index bcc46f8fa..80bb48d32 100644
--- a/src/lib/config.h
+++ b/src/lib/config.h
@@ -1002,6 +1002,7 @@ public:
 	void write_cinemas () const;
 	void link (boost::filesystem::path new_file) const;
 	void copy_and_link (boost::filesystem::path new_file) const;
+	bool have_write_permission () const;
 
 	void save_template (boost::shared_ptr<const Film> film, std::string name) const;
 	bool existing_template (std::string name) const;
diff --git a/src/tools/dcpomatic_player.cc b/src/tools/dcpomatic_player.cc
index 7313daf0f..0f1ed00b3 100644
--- a/src/tools/dcpomatic_player.cc
+++ b/src/tools/dcpomatic_player.cc
@@ -136,7 +136,7 @@ public:
 #endif
 
 		_config_changed_connection = Config::instance()->Changed.connect (boost::bind (&DOMFrame::config_changed, this));
-		config_changed ();
+		update_from_config ();
 
 		Bind (wxEVT_MENU, boost::bind (&DOMFrame::file_open, this), ID_file_open);
 		Bind (wxEVT_MENU, boost::bind (&DOMFrame::file_add_ov, this), ID_file_add_ov);
@@ -467,12 +467,14 @@ private:
 #endif
 
 #ifdef __WXOSX__
-		_file_menu->Append (wxID_PREFERENCES, _("&Preferences...\tCtrl-P"));
+		wxMenuItem* prefs = _file_menu->Append (wxID_PREFERENCES, _("&Preferences...\tCtrl-P"));
 #else
 		wxMenu* edit = new wxMenu;
-		edit->Append (wxID_PREFERENCES, _("&Preferences...\tCtrl-P"));
+		wxMenuItem* prefs = edit->Append (wxID_PREFERENCES, _("&Preferences...\tCtrl-P"));
 #endif
 
+		prefs->Enable (Config::instance()->have_write_permission());
+
 		_cpl_menu = new wxMenu;
 
 		wxMenu* view = new wxMenu;
@@ -632,6 +634,10 @@ private:
 
 	void edit_preferences ()
 	{
+		if (!Config::instance()->have_write_permission()) {
+			return;
+		}
+
 		if (!_config_dialog) {
 			_config_dialog = create_player_config_dialog ();
 		}
@@ -808,16 +814,26 @@ private:
 		/* Instantly save any config changes when using the player GUI */
 		try {
 			Config::instance()->write_config();
-		} catch (exception& e) {
+		} catch (FileError& e) {
 			error_dialog (
 				this,
-				wxString::Format (
+				wxString::Format(
 					_("Could not write to config file at %s.  Your changes have not been saved."),
-					std_to_wx (Config::instance()->cinemas_file().string()).data()
+					std_to_wx(e.file().string())
 					)
 				);
+		} catch (exception& e) {
+			error_dialog (
+				this,
+				_("Could not write to config file.  Your changes have not been saved.")
+				);
 		}
 
+		update_from_config ();
+	}
+
+	void update_from_config ()
+	{
 		for (int i = 0; i < _history_items; ++i) {
 			delete _file_menu->Remove (ID_file_history + i);
 		}
-- 
2.30.2