turn PCAPDLL into a singleton

include/icsneo/platform/windows/internal/pcapdll.h

@@ -12,8 +12,7 @@ namespace icsneo {
 class PCAPDLL {
 public:
 	// The first time we use the DLL we keep it in here and it won't get freed until the user unloads us (for speed reasons)
-	static std::shared_ptr<PCAPDLL> lazyLoadHolder;
-	static bool lazyLoaded;
+	static const PCAPDLL& getInstance();
 
 	// Functions
 	typedef int(__cdecl* PCAPFINDDEVICE)(char* source, struct pcap_rmtauth* auth, pcap_if_t** alldevs, char* errbuf);
@@ -45,14 +44,14 @@ public:
 	PCAPCREATESRCSTR createsrcstr;
 	PCAPSETBUFF setbuff;
 
-	PCAPDLL();
-	~PCAPDLL() { closeDLL(); }
-	bool ok() const { return dll != nullptr; }
+
+	~PCAPDLL();
+	bool ok() const;
 private:
+	PCAPDLL();
 	HINSTANCE dll;
 	void closeDLL();
 };
-
 }
 
 #endif

include/icsneo/platform/windows/pcap.h

@@ -26,7 +26,7 @@ public:
 	bool isOpen();
 	bool close();
 private:
-	PCAPDLL pcap;
+	const PCAPDLL& pcap;
 	char errbuf[PCAP_ERRBUF_SIZE] = { 0 };
 	neodevice_t& device;
 	uint8_t deviceMAC[6];

platform/windows/internal/pcapdll.cpp

@@ -2,15 +2,31 @@
 
 using namespace icsneo;
 
-std::shared_ptr<PCAPDLL> PCAPDLL::lazyLoadHolder;
-bool PCAPDLL::lazyLoaded = false;
+const PCAPDLL& PCAPDLL::getInstance()
+{
+	static PCAPDLL instance;
+	return instance;
+}
 
-PCAPDLL::PCAPDLL() {
-	if(!lazyLoaded) {
-		lazyLoaded = true;
-		lazyLoadHolder = std::make_shared<PCAPDLL>();
-	}
+PCAPDLL::~PCAPDLL()
+{ 
+	closeDLL();
+}
 
+void PCAPDLL::closeDLL()
+{
+	if (dll)
+		FreeLibrary(dll);
+	dll = nullptr;
+}
+
+bool PCAPDLL::ok() const 
+{ 
+	return dll != nullptr; 
+}
+
+PCAPDLL::PCAPDLL() 
+{
 	dll = LoadLibrary("wpcap.dll");
 
 	if(dll == NULL) {
@@ -43,9 +59,3 @@ PCAPDLL::PCAPDLL() {
 		}
 	}
 }
-
-void PCAPDLL::closeDLL() {
-	if(dll)
-		FreeLibrary(dll);
-	dll = nullptr;
-}

platform/windows/pcap.cpp

@@ -18,7 +18,7 @@ std::vector<PCAP::NetworkInterface> PCAP::knownInterfaces;
 
 std::vector<PCAP::PCAPFoundDevice> PCAP::FindAll() {
 	std::vector<PCAPFoundDevice> foundDevices;
-	PCAPDLL pcap;
+	const PCAPDLL& pcap = PCAPDLL::getInstance();
 	if(!pcap.ok()) {
 		EventManager::GetInstance().add(APIEvent::Type::PCAPCouldNotStart, APIEvent::Severity::Error);
 		return std::vector<PCAPFoundDevice>();
@@ -177,7 +177,7 @@ bool PCAP::IsHandleValid(neodevice_handle_t handle) {
 	return (netifIndex < knownInterfaces.size());
 }
 
-PCAP::PCAP(const device_eventhandler_t& err, neodevice_t& forDevice) : Driver(err), device(forDevice) {
+PCAP::PCAP(const device_eventhandler_t& err, neodevice_t& forDevice) : Driver(err), device(forDevice), pcap(PCAPDLL::getInstance()) {
 	if(IsHandleValid(device.handle)) {
 		interface = knownInterfaces[(device.handle >> 24) & 0xFF];
 		interface.fp = nullptr; // We're going to open our own connection to the interface. This should already be nullptr but just in case.