Added code to make pointer vector be thread safe

Common++/header/PointerVector.h

@@ -3,6 +3,7 @@
 #include <stdio.h>
 #include <stdint.h>
 #include <vector>
+#include <mutex>
 
 /// @file
 
@@ -12,14 +13,24 @@
  */
 namespace pcpp
 {
+	/**
+ 	* @struct NullMutex
+ 	* A struct containing standard mutex operation but does not perform any action.
+ 	* This mutex is used when the user decides PointerVector not be thread safe which be default
+	*/
+	struct NullMutex {
+		void lock() const {}
+		void unlock() const {}
+	};
 
 	/**
 	 * @class PointerVector
 	 * A template class for representing a std::vector of pointers. Once (a pointer to) an element is added to this vector,
 	 * the element responsibility moves to the vector, meaning the PointerVector will free the object once it's removed from the vector
-	 * This class wraps std::vector and adds the capability of freeing objects once they're removed from it
+	 * This class wraps std::vector and adds the capability of freeing objects once they're removed from it. By default NullMutex is used
+	 * but when user wants the PointerVector to be thread safe; they need to pass the mutex as  the template argument to PointerVector
 	 */
-	template<typename T>
+	template<typename T, typename Mutex=pcpp::NullMutex>
 	class PointerVector
 	{
 	public:
@@ -43,6 +54,7 @@ namespace pcpp
 		 */
 		~PointerVector()
 		{
+			std::lock_guard<Mutex> lk(m_Mutex);
 			for (auto iter : m_Vector)
 			{
 				delete iter;
@@ -57,6 +69,7 @@ namespace pcpp
 		{
 			try
 			{
+				std::lock_guard<Mutex> lk(other.m_Mutex);
 				for (const auto iter : other)
 				{
 					T* objCopy = new T(*iter);
@@ -70,7 +83,7 @@ namespace pcpp
 						throw;
 					}
 				}
-			}
+			} 
 			catch (const std::exception&)
 			{
 				for (auto obj : m_Vector)
@@ -86,6 +99,7 @@ namespace pcpp
 		 */
 		void clear()
 		{
+			std::lock_guard<Mutex> lk(m_Mutex);
 			for (auto iter : m_Vector)
 			{
 				delete iter;
@@ -97,31 +111,51 @@ namespace pcpp
 		/**
 		 * Add a new (pointer to an) element to the vector
 		 */
-		void pushBack(T* element) { m_Vector.push_back(element); }
+		void pushBack(T* element)
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			m_Vector.push_back(element);
+		}
 
 		/**
 		 * Get the first element of the vector
 		 * @return An iterator object pointing to the first element of the vector
 		 */
-		VectorIterator begin() { return m_Vector.begin(); }
+		VectorIterator begin()
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			return m_Vector.begin();
+		}
 
 		/**
 		 * Get the first element of a constant vector
 		 * @return A const iterator object pointing to the first element of the vector
 		 */
-		ConstVectorIterator begin() const { return m_Vector.begin(); }
+		ConstVectorIterator begin() const
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			return m_Vector.begin();
+		}
 
 		/**
 		 * Get the last element of the vector
 		 * @return An iterator object pointing to the last element of the vector
 		 */
-		VectorIterator end() { return m_Vector.end(); }
+		VectorIterator end()
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			return m_Vector.end();
+		}
 
 		/**
 		 * Get the last element of a constant vector
 		 * @return A const iterator object pointing to the last element of the vector
 		 */
-		ConstVectorIterator end() const { return m_Vector.end(); }
+		ConstVectorIterator end() const
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			return m_Vector.end();
+		}
 
 
 		//inline size_t size() { return m_Vector.size(); }
@@ -130,13 +164,21 @@ namespace pcpp
 		 * Get number of elements in the vector
 		 * @return The number of elements in the vector
 		 */
-		size_t size() const { return m_Vector.size(); }
+		size_t size() const
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			return m_Vector.size();
+		}
 
 		/**
 		 * Returns a pointer of the first element in the vector
 		 * @return A pointer of the first element in the vector
 		 */
-		T* front() { return m_Vector.front(); }
+		T* front()
+		{
+			std::lock_guard<Mutex> lk(m_Mutex);
+			return m_Vector.front();
+		}
 
 		/**
 		 * Removes from the vector a single element (position). Once the element is erased, it's also freed
@@ -145,6 +187,7 @@ namespace pcpp
 		 */
 		VectorIterator erase(VectorIterator position)
 		{
+			std::lock_guard<Mutex> lk(m_Mutex);
 			delete (*position);
 			return m_Vector.erase(position);
 		}
@@ -158,7 +201,10 @@ namespace pcpp
 		{
 			T* result = (*position);
 			VectorIterator tempPos = position;
-			tempPos = m_Vector.erase(tempPos);
+			{
+				std::lock_guard<Mutex> lk(m_Mutex);
+				tempPos = m_Vector.erase(tempPos);
+			}
 			position = tempPos;
 			return result;
 		}
@@ -170,6 +216,7 @@ namespace pcpp
 		 */
 		T* at(int index)
 		{
+			std::lock_guard<Mutex> lk(m_Mutex);
 			return m_Vector.at(index);
 		}
 
@@ -180,11 +227,13 @@ namespace pcpp
 		 */
 		const T* at(int index) const
 		{
+			std::lock_guard<Mutex> lk(m_Mutex);
 			return m_Vector.at(index);
 		}
 
 	private:
 		std::vector<T*> m_Vector;
+		mutable Mutex m_Mutex;
 	};
 
 } // namespace pcpp