WIP: Variant task

1 files changed, 52 insertions, 0 deletions

diff --git a/src/server/Task.hpp b/src/server/Task.hpp
index 99fe347d..25f76260 100644
--- a/src/server/Task.hpp
+++ b/src/server/Task.hpp
@@ -24,12 +24,55 @@
 #include <memory>
 #include <ostream>
 
+#include <boost/variant/variant.hpp>
+
 namespace Ingen {
 namespace Server {
 
 class BlockImpl;
 class RunContext;
 
+struct SingleTask;
+struct MultiTask;
+struct SeqTask;
+struct ParTask;
+
+using Task = boost::variant<SingleTask, SeqTask, ParTask>;
+
+using TaskChildren = std::deque<std::unique_ptr<Task>>;
+
+struct SingleTask {
+	BlockImpl* block; ///< Block to run
+};
+
+struct MultiTask {
+	/** Prepend a child to this task. */
+	template<typename... Args>
+	void emplace_front(Args... args) {
+		children.emplace_front(new Task(std::forward<Args>(args)...));
+	}
+
+	TaskChildren children; ///< Child tasks
+};
+
+struct SeqTask : MultiTask {
+};
+
+struct ParTask : MultiTask {
+	ParTask() = default;
+
+	ParTask(ParTask&& task)
+		: done_end(task.done_end)
+		, next(task.next.load())
+		, done(task.done.load())
+	{}
+
+	unsigned              done_end{0};  ///< Index of rightmost done sub-task
+	std::atomic<unsigned> next{0};      ///< Index of next sub-task
+	std::atomic<bool>     done{false};  ///< Completion phase
+};
+
+	#if 0
 class Task {
 public:
 	enum class Mode {
@@ -112,6 +155,15 @@ private:
 	std::atomic<bool>     _done;      ///< Completion phase
 };
 
+#endif
+
+void run(Task& task, RunContext& context);
+
+std::unique_ptr<Task> simplify(std::unique_ptr<Task>&& task);
+
+/** Steal a child task from this task. */
+Task* steal(ParTask& task, RunContext& context);
+
 } // namespace Server
 } // namespace Ingen