1 files changed, 107 insertions, 0 deletions
diff --git a/src/server/UndoStack.hpp b/src/server/UndoStack.hpp
new file mode 100644
index 00000000..6ce6475f
--- /dev/null
+++ b/src/server/UndoStack.hpp
@@ -0,0 +1,107 @@
+/*
+  This file is part of Ingen.
+  Copyright 2016 David Robillard <http://drobilla.net/>
+
+  Ingen is free software: you can redistribute it and/or modify it under the
+  terms of the GNU Affero General Public License as published by the Free
+  Software Foundation, either version 3 of the License, or any later version.
+
+  Ingen 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 Affero General Public License for details.
+
+  You should have received a copy of the GNU Affero General Public License
+  along with Ingen.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef INGEN_ENGINE_UNDOSTACK_HPP
+#define INGEN_ENGINE_UNDOSTACK_HPP
+
+#include <ctime>
+#include <deque>
+
+#include "ingen/AtomSink.hpp"
+#include "ingen/ingen.h"
+#include "lv2/lv2plug.in/ns/ext/atom/atom.h"
+#include "serd/serd.h"
+#include "sratom/sratom.h"
+
+namespace Ingen {
+
+class URIMap;
+class URIs;
+
+namespace Server {
+
+class INGEN_API UndoStack : public AtomSink {
+public:
+	struct Entry {
+		Entry(time_t time=0) : time(time) {}
+
+		Entry(const Entry& copy)
+			: time(copy.time)
+		{
+			for (const LV2_Atom* ev : copy.events) {
+				push_event(ev);
+			}
+		}
+
+		~Entry() { clear(); }
+
+		Entry& operator=(const Entry& rhs) {
+			clear();
+			time = rhs.time;
+			for (const LV2_Atom* ev : rhs.events) {
+				push_event(ev);
+			}
+			return *this;
+		}
+
+		void clear() {
+			for (LV2_Atom* ev : events) {
+				free(ev);
+			}
+			events.clear();
+		}
+
+		void push_event(const LV2_Atom* ev) {
+			const uint32_t size = lv2_atom_total_size(ev);
+			LV2_Atom*      copy = (LV2_Atom*)malloc(size);
+			memcpy(copy, ev, size);
+			events.push_front(copy);
+		}
+
+		time_t                time;
+		std::deque<LV2_Atom*> events;
+	};
+
+	UndoStack(URIs& uris, URIMap& map) : _uris(uris), _map(map), _depth(0) {}
+
+	int  start_entry();
+	bool write(const LV2_Atom* msg, int32_t default_id=0);
+	int  finish_entry();
+
+	bool  empty() const { return _stack.empty(); }
+	Entry pop();
+
+	void save(FILE* stream, const char* name="undo");
+
+private:
+	bool ignore_later_event(const LV2_Atom* first,
+	                        const LV2_Atom* second) const;
+
+	void write_entry(Sratom*         sratom,
+	                 SerdWriter*     writer,
+	                 const SerdNode* subject,
+	                 const Entry&    entry);
+
+	URIs&             _uris;
+	URIMap&           _map;
+	std::deque<Entry> _stack;
+	int               _depth;
+};
+
+} // namespace Server
+} // namespace Ingen
+
+#endif // INGEN_ENGINE_UNDOSTACK_HPP