Added event callback functionality. EventManager now uses multiple mutexes to lock events, errors, callbacks, and downgradedThreads separately. Wrote single-threaded test for event callbacks.

include/icsneo/api/eventcallback.h

@@ -0,0 +1,39 @@
+#ifndef __EVENTCALLBACK_H_
+#define __EVENTCALLBACK_H_
+
+#include <functional>
+#include <memory>
+#include "event.h"
+
+namespace icsneo {
+
+class EventCallback {
+public:
+    typedef std::function< void( std::shared_ptr<APIEvent> ) > fn_eventCallback;
+
+    EventCallback(fn_eventCallback cb, std::shared_ptr<EventFilter> f) : callback(cb), filter(f) {}
+    EventCallback(fn_eventCallback cb, EventFilter f = EventFilter()) : callback(cb), filter(std::make_shared<EventFilter>(f)) {}
+
+    // Allow the filter to be placed first if the user wants (maybe in the case of a lambda)
+	EventCallback(std::shared_ptr<EventFilter> f, fn_eventCallback cb) : callback(cb), filter(f) {}
+	EventCallback(EventFilter f, fn_eventCallback cb) : callback(cb), filter(std::make_shared<EventFilter>(f)) {}
+
+    virtual bool callIfMatch(const std::shared_ptr<APIEvent>& event) const {
+		bool ret = filter->match(*event);
+		if(ret)
+			callback(event);
+		return ret;
+	}
+
+    const EventFilter& getFilter() const { return *filter; }
+	const fn_eventCallback& getCallback() const { return callback; }
+
+private:
+    fn_eventCallback callback;
+    std::shared_ptr<EventFilter> filter;
+
+};
+
+}
+
+#endif