Add WinNet_ActivateConnectivityMonitor()

6 files changed, 360 insertions, 0 deletions

diff --git a/windows/winnet/src/winnet/netmonitor.cpp b/windows/winnet/src/winnet/netmonitor.cpp
new file mode 100644
index 0000000000..6ccaf3d64a
--- /dev/null
+++ b/windows/winnet/src/winnet/netmonitor.cpp
@@ -0,0 +1,201 @@
+#include "stdafx.h"
+#include "netmonitor.h"
+#include <libcommon/error.h>
+#include <libcommon/memory.h>
+#include <libcommon/synchronization.h>
+
+namespace
+{
+
+bool ValidInterfaceType(const MIB_IF_ROW2 &iface)
+{
+	switch (iface.InterfaceLuid.Info.IfType)
+	{
+		case IF_TYPE_SOFTWARE_LOOPBACK:
+		case IF_TYPE_TUNNEL:
+		{
+			return false;
+		}
+	}
+
+	if (FALSE == iface.InterfaceAndOperStatusFlags.ConnectorPresent
+		|| FALSE != iface.InterfaceAndOperStatusFlags.EndPointInterface)
+	{
+		return false;
+	}
+
+	return true;
+}
+
+} // anonyomus namespace
+
+NetMonitor::NetMonitor(NetMonitor::Notifier notifier, bool &currentConnectivity)
+	: m_notifier(notifier)
+	, m_connected(false)
+	, m_notificationHandle(nullptr)
+{
+	createCache();
+	updateConnectivity();
+
+	currentConnectivity = m_connected;
+
+	const auto status = NotifyIpInterfaceChange(AF_UNSPEC, callback, this, FALSE, &m_notificationHandle);
+
+	THROW_UNLESS(NO_ERROR, status, "Register interface change notification");
+}
+
+NetMonitor::~NetMonitor()
+{
+	CancelMibChangeNotify2(m_notificationHandle);
+}
+
+void NetMonitor::createCache()
+{
+	MIB_IF_TABLE2 *table;
+
+	const auto status = GetIfTable2(&table);
+
+	THROW_UNLESS(NO_ERROR, status, "Acquire network interface table");
+
+	common::memory::ScopeDestructor sd;
+
+	sd += [table]()
+	{
+		FreeMibTable(table);
+	};
+
+	for (ULONG i = 0; i < table->NumEntries; ++i)
+	{
+		addCacheEntry(table->Table[i]);
+	}
+}
+
+void NetMonitor::addCacheEntry(const MIB_IF_ROW2 &iface)
+{
+	CacheEntry e;
+
+	if (false == ValidInterfaceType(iface))
+	{
+		e.luid = iface.InterfaceLuid.Value;
+		e.valid = false;
+		e.connected = false;
+	}
+	else
+	{
+		e.luid = iface.InterfaceLuid.Value;
+		e.valid = true;
+		e.connected = (MediaConnectStateConnected == iface.MediaConnectState);
+	}
+
+	m_cache.insert(std::make_pair(e.luid, e));
+}
+
+void NetMonitor::updateConnectivity()
+{
+	for (const auto cacheEntryIter : m_cache)
+	{
+		const auto entry = cacheEntryIter.second;
+
+		if (entry.valid && entry.connected)
+		{
+			m_connected = true;
+			return;
+		}
+	}
+
+	m_connected = false;
+}
+
+//static
+void __stdcall NetMonitor::callback(void *context, MIB_IPINTERFACE_ROW *hint, MIB_NOTIFICATION_TYPE updateType)
+{
+	auto thiz = reinterpret_cast<NetMonitor *>(context);
+
+	common::sync::ScopeLock<> processingLock(thiz->m_processingMutex);
+
+	switch (updateType)
+	{
+		case MibAddInstance:
+		{
+			MIB_IF_ROW2 iface = { 0 };
+			iface.InterfaceLuid = hint->InterfaceLuid;
+
+			if (NO_ERROR != GetIfEntry2(&iface))
+			{
+				// Failed to query interface.
+				return;
+			}
+
+			thiz->addCacheEntry(iface);
+
+			break;
+		}
+		case MibDeleteInstance:
+		{
+			const auto cacheEntry = thiz->m_cache.find(hint->InterfaceLuid.Value);
+
+			if (thiz->m_cache.end() != cacheEntry)
+			{
+				cacheEntry->second.connected = false;
+			}
+
+			break;
+		}
+		case MibParameterNotification:
+		{
+			auto cacheEntry = thiz->m_cache.find(hint->InterfaceLuid.Value);
+
+			if (thiz->m_cache.end() == cacheEntry)
+			{
+				//
+				// A change occurred on an interface that we're not tracking.
+				// Perhaps the MibAddInstance logic failed for some reason.
+				//
+
+				MIB_IF_ROW2 iface = { 0 };
+				iface.InterfaceLuid = hint->InterfaceLuid;
+
+				if (NO_ERROR != GetIfEntry2(&iface))
+				{
+					// Failed to query interface.
+					return;
+				}
+
+				thiz->addCacheEntry(iface);
+			}
+			else
+			{
+				//
+				// Abort processing if this is a known interface that we don't care about.
+				//
+				if (false == cacheEntry->second.valid)
+				{
+					return;
+				}
+
+				//
+				// Update cache.
+				//
+
+				MIB_IF_ROW2 iface = { 0 };
+				iface.InterfaceLuid = hint->InterfaceLuid;
+
+				const auto status = GetIfEntry2(&iface);
+
+				cacheEntry->second.connected =
+					(NO_ERROR == status ? MediaConnectStateConnected == iface.MediaConnectState : false);
+			}
+
+			break;
+		}
+	}
+
+	const auto previousConnectivity = thiz->m_connected;
+
+	thiz->updateConnectivity();
+
+	if (previousConnectivity != thiz->m_connected)
+	{
+		thiz->m_notifier(thiz->m_connected);
+	}
+}
diff --git a/windows/winnet/src/winnet/netmonitor.h b/windows/winnet/src/winnet/netmonitor.h
new file mode 100644
index 0000000000..b8e418b82d
--- /dev/null
+++ b/windows/winnet/src/winnet/netmonitor.h
@@ -0,0 +1,55 @@
+#pragma once
+
+#include <map>
+#include <string>
+#include <cstdint>
+#include <mutex>
+#include <functional>
+#include <winsock2.h>
+#include <ws2ipdef.h>
+#include <iphlpapi.h>
+#include <windows.h>
+
+class NetMonitor
+{
+public:
+
+	//
+	// Connectivity changed.
+	// true = connected, false = disconnected.
+	//
+	using Notifier = std::function<void(bool)>;
+
+	NetMonitor(Notifier notifier, bool &currentConnectivity);
+	~NetMonitor();
+
+private:
+
+	std::mutex m_processingMutex;
+
+	Notifier m_notifier;
+
+	struct CacheEntry
+	{
+		// Unique interface identifier.
+		uint64_t luid;
+
+		// Whether this is a physical adapter or not.
+		bool valid;
+
+		// Last known state.
+		bool connected;
+	};
+
+	std::map<uint64_t, CacheEntry> m_cache;
+
+	bool m_connected;
+
+	HANDLE m_notificationHandle;
+
+	void createCache();
+	void addCacheEntry(const MIB_IF_ROW2 &iface);
+	void updateConnectivity();
+
+	static void __stdcall callback(void *context, MIB_IPINTERFACE_ROW *hint, MIB_NOTIFICATION_TYPE updateType);
+};
diff --git a/windows/winnet/src/winnet/winnet.cpp b/windows/winnet/src/winnet/winnet.cpp
index ba14c737da..9741613457 100644
--- a/windows/winnet/src/winnet/winnet.cpp
+++ b/windows/winnet/src/winnet/winnet.cpp
@@ -3,9 +3,17 @@
 #include "NetworkInterfaces.h"

 #include "interfaceutils.h"

 #include "libcommon/error.h"

+#include "netmonitor.h"

 #include <cstdint>

 #include <stdexcept>

 

+namespace

+{

+

+NetMonitor *g_NetMonitor = nullptr;

+

+} //anonymous namespace

+

 extern "C"

 WINNET_LINKAGE

 WINNET_ETM_STATUS

@@ -134,3 +142,69 @@ WinNet_ReleaseString(
 	{

 	}

 }

+

+extern "C"
+WINNET_LINKAGE
+WINNET_ACM_STATUS
+WINNET_API
+WinNet_ActivateConnectivityMonitor(
+	WinNetConnectivityMonitorCallback callback,
+	uint8_t *currentConnectivity,
+	WinNetErrorSink errorSink,
+	void* errorSinkContext
+)
+{
+	try

+	{

+		if (nullptr != g_NetMonitor)

+		{

+			throw std::runtime_error("Cannot activate connectivity monitor twice");

+		}

+

+		auto forwarder = [callback](bool connected)

+		{

+			callback(static_cast<uint8_t>(connected));

+		};

+

+		bool connected = false;

+

+		g_NetMonitor = new NetMonitor(forwarder, connected);

+

+		if (nullptr != currentConnectivity)

+		{

+			*currentConnectivity = static_cast<uint8_t>(connected);

+		}

+

+		return WINNET_ACM_STATUS::SUCCESS;

+	}

+	catch (std::exception &err)

+	{

+		if (nullptr != errorSink)

+		{

+			errorSink(err.what(), errorSinkContext);

+		}

+

+		return WINNET_ACM_STATUS::FAILURE;

+	}

+	catch (...)

+	{

+		return WINNET_ACM_STATUS::FAILURE;

+	}

+}
+
+extern "C"
+WINNET_LINKAGE
+void
+WINNET_API
+WinNet_DeactivateConnectivityMonitor(
+)
+{
+	try
+	{
+		delete g_NetMonitor;
+		g_NetMonitor = nullptr;
+	}
+	catch (...)
+	{
+	}
+}
diff --git a/windows/winnet/src/winnet/winnet.h b/windows/winnet/src/winnet/winnet.h
index b5771f5b5a..c3464d4c03 100644
--- a/windows/winnet/src/winnet/winnet.h
+++ b/windows/winnet/src/winnet/winnet.h
@@ -71,3 +71,29 @@ WINNET_API
 WinNet_ReleaseString(
 	wchar_t *str
 );
+
+typedef void (WINNET_API *WinNetConnectivityMonitorCallback)(uint8_t connected);
+
+enum class WINNET_ACM_STATUS : uint32_t
+{
+	SUCCESS = 0,
+	FAILURE = 1,
+};
+
+extern "C"
+WINNET_LINKAGE
+WINNET_ACM_STATUS
+WINNET_API
+WinNet_ActivateConnectivityMonitor(
+	WinNetConnectivityMonitorCallback callback,
+	uint8_t *currentConnectivity,
+	WinNetErrorSink errorSink,
+	void* errorSinkContext
+);
+
+extern "C"
+WINNET_LINKAGE
+void
+WINNET_API
+WinNet_DeactivateConnectivityMonitor(
+);
diff --git a/windows/winnet/src/winnet/winnet.vcxproj b/windows/winnet/src/winnet/winnet.vcxproj
index e43b928d6c..fd10ec40fd 100644
--- a/windows/winnet/src/winnet/winnet.vcxproj
+++ b/windows/winnet/src/winnet/winnet.vcxproj
@@ -22,6 +22,7 @@
     <ClCompile Include="dllmain.cpp" />
     <ClCompile Include="InterfacePair.cpp" />
     <ClCompile Include="interfaceutils.cpp" />
+    <ClCompile Include="netmonitor.cpp" />
     <ClCompile Include="NetworkInterfaces.cpp" />
     <ClCompile Include="stdafx.cpp" />
     <ClCompile Include="winnet.cpp" />
@@ -29,6 +30,7 @@
   <ItemGroup>
     <ClInclude Include="InterfacePair.h" />
     <ClInclude Include="interfaceutils.h" />
+    <ClInclude Include="netmonitor.h" />
     <ClInclude Include="NetworkInterfaces.h" />
     <ClInclude Include="stdafx.h" />
     <ClInclude Include="targetver.h" />
diff --git a/windows/winnet/src/winnet/winnet.vcxproj.filters b/windows/winnet/src/winnet/winnet.vcxproj.filters
index 2d320e7908..3ac5a14717 100644
--- a/windows/winnet/src/winnet/winnet.vcxproj.filters
+++ b/windows/winnet/src/winnet/winnet.vcxproj.filters
@@ -7,6 +7,7 @@
     <ClCompile Include="NetworkInterfaces.cpp" />
     <ClCompile Include="InterfacePair.cpp" />
     <ClCompile Include="interfaceutils.cpp" />
+    <ClCompile Include="netmonitor.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="stdafx.h" />
@@ -15,6 +16,7 @@
     <ClInclude Include="NetworkInterfaces.h" />
     <ClInclude Include="InterfacePair.h" />
     <ClInclude Include="interfaceutils.h" />
+    <ClInclude Include="netmonitor.h" />
   </ItemGroup>
   <ItemGroup>
     <None Include="winnet.def" />