Bug 1561005 - Add nsINetworkLinkService.networkID r=michal

Differential Revision: https://phabricator.services.mozilla.com/D35683

--HG--
extra : moz-landing-system : lando

netwerk/base/nsINetworkLinkService.idl

@@ -45,6 +45,12 @@ interface nsINetworkLinkService : nsISupports
    * The type of network connection.
    */
   readonly attribute unsigned long linkType;
+
+  /**
+   * A string uniquely identifying the current active network interfaces.
+   * Empty when there are no active network interfaces.
+   */
+  readonly attribute ACString networkID;
 };
 
 %{C++

netwerk/system/win32/nsNotifyAddrListener.cpp

@@ -106,10 +106,10 @@ NS_IMPL_ISUPPORTS(nsNotifyAddrListener, nsINetworkLinkService, nsIRunnable,
                   nsIObserver)
 
 nsNotifyAddrListener::nsNotifyAddrListener()
-    : mLinkUp(true)  // assume true by default
-      ,
+    : mLinkUp(true),  // assume true by default
       mStatusKnown(false),
       mCheckAttempted(false),
+      mMutex("nsNotifyAddrListener::mMutex"),
       mCheckEvent(nullptr),
       mShutdown(false),
       mIPInterfaceChecksum(0),
@@ -150,6 +150,13 @@ nsNotifyAddrListener::GetLinkType(uint32_t* aLinkType) {
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsNotifyAddrListener::GetNetworkID(nsACString& aNetworkID) {
+  MutexAutoLock lock(mMutex);
+  aNetworkID = mNetworkId;
+  return NS_OK;
+}
+
 static bool macAddr(BYTE addr[], DWORD len, char* buf, size_t buflen) {
   buf[0] = '\0';
   if (!addr || !len || (len * 3 > buflen)) {
@@ -210,6 +217,7 @@ bool nsNotifyAddrListener::findMac(char* gateway) {
             break;
           }
           LOG(("networkid: id %s\n", output.get()));
+          MutexAutoLock lock(mMutex);
           if (mNetworkId != output) {
             // new id
             Telemetry::Accumulate(Telemetry::NETWORK_ID2, 1);

netwerk/system/win32/nsNotifyAddrListener.h

@@ -15,6 +15,7 @@
 #include "nsThreadUtils.h"
 #include "nsCOMPtr.h"
 #include "mozilla/TimeStamp.h"
+#include "mozilla/Mutex.h"
 
 class nsNotifyAddrListener : public nsINetworkLinkService,
                              public nsIRunnable,
@@ -71,6 +72,8 @@ class nsNotifyAddrListener : public nsINetworkLinkService,
   // Figure out the current network identification
   void calculateNetworkId(void);
   bool findMac(char* gateway);
+
+  mozilla::Mutex mMutex;
   nsCString mNetworkId;
 
   HANDLE mCheckEvent;