Implement internet reachability monitor

OpenVPN Adapter/OpenVPNReachability+Internal.h

@@ -11,8 +11,6 @@
 
 @interface OpenVPNReachability (Internal)
 
-@property OpenVPNReachabilityTracker *reachabilityTracker;
-
 - (void)updateReachabilityStatus:(OpenVPNReachabilityStatus)status;
 
 @end

OpenVPN Adapter/OpenVPNReachability.h

@@ -12,8 +12,9 @@
 @interface OpenVPNReachability : NSObject
 
 @property (readonly, nonatomic) OpenVPNReachabilityStatus reachabilityStatus;
+@property (copy, nonatomic) void (^ _Nullable reachabilityStatusChangedBlock)(OpenVPNReachabilityStatus reachabilityStatus);
 
-- (nonnull instancetype)initWatchingWWAN:(BOOL)watchWWAN watchingWiFi:(BOOL)watchWiFi;
+- (nonnull instancetype)init;
 
 - (void)startTracking;
 - (void)stopTracking;

OpenVPN Adapter/OpenVPNReachability.mm

@@ -9,13 +9,49 @@
 #import "OpenVPNReachability.h"
 #import "OpenVPNReachability+Internal.h"
 
+@interface OpenVPNReachability () {
+    OpenVPNReachabilityStatus _reachabilityStatus;
+}
+
+@property (assign, nonatomic) OpenVPNReachabilityTracker *reachabilityTracker;
+
+@end
+
 @implementation OpenVPNReachability (Internal)
 
-
+- (void)updateReachabilityStatus:(OpenVPNReachabilityStatus)status {
+    _reachabilityStatus = status;
+    if (self.reachabilityStatusChangedBlock) {
+        self.reachabilityStatusChangedBlock(status);
+    }
+}
 
 @end
 
 @implementation OpenVPNReachability
 
+- (OpenVPNReachabilityStatus)reachabilityStatus {
+    return _reachabilityStatus;
+}
+
+- (nonnull instancetype)init {
+    self = [super init];
+    if (self) {
+        self.reachabilityTracker = new OpenVPNReachabilityTracker(true, false, (__bridge void *)self);
+    }
+    return self;
+}
+
+- (void)startTracking {
+    self.reachabilityTracker->reachability_tracker_schedule();
+}
+
+- (void)stopTracking {
+    self.reachabilityTracker->reachability_tracker_cancel();
+}
+
+- (void)dealloc {
+    delete self.reachabilityTracker;
+}
 
 @end