Fixed multithreading issue with eventmanager

api/icsneocpp/eventmanager.cpp

@@ -12,11 +12,11 @@ EventManager& EventManager::GetInstance() {
 }
 
 void EventManager::ResetInstance() {
-	singleton = nullptr;
+	singleton = std::unique_ptr<EventManager>(new EventManager());
 }
 
 void EventManager::get(std::vector<APIEvent>& eventOutput, size_t max, EventFilter filter) {
-	std::lock_guard<std::mutex> lk(mutex);
+	std::unique_lock<std::shared_mutex> lk(mutex);
 
 	if(max == 0) // A limit of 0 indicates no limit
 		max = (size_t)-1;
@@ -27,34 +27,34 @@ void EventManager::get(std::vector<APIEvent>& eventOutput, size_t max, EventFilt
 	while(it != events.end()) {
 		if(filter.match(*it)) {
 			eventOutput.push_back(*it);
-			events.erase(it++);
+			it = events.erase(it);
 			if(count++ >= max)
 				break; // We now have as many written to output as we can
 		} else {
-			std::advance(it, 1);
+			it++;
 		}
 	}
 }
 
 /**
  * Removes the returned error from the map
- * If no error was found, return a default-constructed event
+ * If no error was found, return a NoErrorFound Info event
  */
 APIEvent EventManager::getLastError() {
-	std::lock_guard<std::mutex> lk(mutex);
+	std::unique_lock<std::shared_mutex> lk(mutex);
 
 	auto it = lastUserErrors.find(std::this_thread::get_id());
 	if(it == lastUserErrors.end()) {
 		return APIEvent(APIEvent::Type::NoErrorFound, APIEvent::Severity::EventInfo);
 	} else {
 		APIEvent ret = it->second;
-		lastUserErrors.erase(it);
+		it = lastUserErrors.erase(it);
 		return ret;
 	}
 }
 
 void EventManager::discard(EventFilter filter) {
-	std::lock_guard<std::mutex> lk(mutex);
+	std::unique_lock<std::shared_mutex> lk(mutex);
 	events.remove_if([&filter](const APIEvent& event) {
 		return filter.match(event);
 	});
@@ -87,7 +87,7 @@ bool EventManager::enforceLimit() {
 	return true;
 }
 
-APIEvent::Severity EventManager::lowestCurrentSeverity() {
+APIEvent::Severity EventManager::lowestCurrentSeverity() const {
 	if(events.empty())
 		return APIEvent::Severity(0);
 
@@ -110,7 +110,7 @@ void EventManager::discardLeastSevere(size_t count) {
 	auto it = events.begin();
 	while(it != events.end()) {
 		if(infoFilter.match(*it)) {
-			events.erase(it++);
+			it = events.erase(it);
 			if(--count == 0)
 				break;
 		} else {
@@ -124,7 +124,7 @@ void EventManager::discardLeastSevere(size_t count) {
 		it = events.begin();
 		while(it != events.end()) {
 			if(warningFilter.match(*it)) {
-				events.erase(it++);
+				it = events.erase(it);
 				if(--count == 0)
 					break;
 			} else {

include/icsneo/api/eventmanager.h

@@ -4,8 +4,10 @@
 #include <vector>
 #include <list>
 #include <mutex>
+#include <shared_mutex>
 #include <functional>
 #include <unordered_map>
+#include<map>
 #include <thread>
 #include "icsneo/api/event.h"
 
@@ -20,7 +22,7 @@ public:
 	static void ResetInstance();
 
 	size_t eventCount(EventFilter filter = EventFilter()) const {
-		std::lock_guard<std::mutex> lk(mutex);
+		std::shared_lock<std::shared_mutex> lk(mutex);
 		return count_internal(filter);
 	};
 
@@ -36,11 +38,11 @@ public:
 	APIEvent getLastError();
 
 	void add(APIEvent event) {
-		std::lock_guard<std::mutex> lk(mutex);
+		std::unique_lock<std::shared_mutex> lk(mutex);
 		add_internal(event);
 	}
 	void add(APIEvent::Type type, APIEvent::Severity severity, const Device* forDevice = nullptr) {
-		std::lock_guard<std::mutex> lk(mutex);
+		std::unique_lock<std::shared_mutex> lk(mutex);
 		add_internal(APIEvent(type, severity, forDevice));
 	}
 
@@ -55,24 +57,28 @@ public:
 			return;
 		}
 
-		std::lock_guard<std::mutex> lk(mutex);
+		std::unique_lock<std::shared_mutex> lk(mutex);
 		eventLimit = newLimit;
 		if(enforceLimit()) 
 			add_internal(APIEvent(APIEvent::Type::TooManyEvents, APIEvent::Severity::EventWarning));
 	}
 
-	size_t getEventLimit() const { return eventLimit; }
-
-
+	size_t getEventLimit() const { 
+		std::shared_lock<std::shared_mutex> lk(mutex);
+		return eventLimit;
+	}
 
 private:
 	EventManager() : mutex(), events(), lastUserErrors(), eventLimit(10000) {}
+	EventManager(const EventManager &other);
+	EventManager& operator=(const EventManager &other);
+
 	// Used by functions for threadsafety
-	mutable std::mutex mutex;
+	mutable std::shared_mutex mutex;
 
 	// Stores all events
 	std::list<APIEvent> events;
-	std::unordered_map<std::thread::id, APIEvent> lastUserErrors;
+	std::map<std::thread::id, APIEvent> lastUserErrors;
 	size_t eventLimit = 10000;
 
 	size_t count_internal(EventFilter filter = EventFilter()) const;
@@ -89,9 +95,10 @@ private:
 	 * If the key id already exists in the map, replace the event of that pair with the new one
 	 */
 	void add_internal_error(APIEvent event) {
-		auto iter = lastUserErrors.find(std::this_thread::get_id());
+		std::thread::id id = std::this_thread::get_id();
+		std::map<std::thread::id, APIEvent>::iterator iter = lastUserErrors.find(id);
 		if(iter == lastUserErrors.end())
-			lastUserErrors.insert(std::make_pair(std::this_thread::get_id(), event));
+			lastUserErrors.insert({id, event});
 		else
 			iter->second = event;
 	}
@@ -120,7 +127,7 @@ private:
 
 	bool enforceLimit(); // Returns whether the limit enforcement resulted in an overflow
 
-	APIEvent::Severity lowestCurrentSeverity();
+	APIEvent::Severity lowestCurrentSeverity() const;
 	void discardLeastSevere(size_t count = 1);
 };