Reachability/Reachability.m
/* |
Copyright (C) 2016 Apple Inc. All Rights Reserved. |
See LICENSE.txt for this sample’s licensing information |
Abstract: |
Basic demonstration of how to use the SystemConfiguration Reachablity APIs. |
*/ |
#import <arpa/inet.h> |
#import <ifaddrs.h> |
#import <netdb.h> |
#import <sys/socket.h> |
#import <netinet/in.h> |
#import <CoreFoundation/CoreFoundation.h> |
#import "Reachability.h" |
#pragma mark IPv6 Support |
//Reachability fully support IPv6. For full details, see ReadMe.md. |
NSString *kReachabilityChangedNotification = @"kNetworkReachabilityChangedNotification"; |
#pragma mark - Supporting functions |
#define kShouldPrintReachabilityFlags 1 |
static void PrintReachabilityFlags(SCNetworkReachabilityFlags flags, const char* comment) |
{ |
#if kShouldPrintReachabilityFlags |
NSLog(@"Reachability Flag Status: %c%c %c%c%c%c%c%c%c %s\n", |
(flags & kSCNetworkReachabilityFlagsIsWWAN) ? 'W' : '-', |
(flags & kSCNetworkReachabilityFlagsReachable) ? 'R' : '-', |
(flags & kSCNetworkReachabilityFlagsTransientConnection) ? 't' : '-', |
(flags & kSCNetworkReachabilityFlagsConnectionRequired) ? 'c' : '-', |
(flags & kSCNetworkReachabilityFlagsConnectionOnTraffic) ? 'C' : '-', |
(flags & kSCNetworkReachabilityFlagsInterventionRequired) ? 'i' : '-', |
(flags & kSCNetworkReachabilityFlagsConnectionOnDemand) ? 'D' : '-', |
(flags & kSCNetworkReachabilityFlagsIsLocalAddress) ? 'l' : '-', |
(flags & kSCNetworkReachabilityFlagsIsDirect) ? 'd' : '-', |
comment |
); |
#endif |
} |
static void ReachabilityCallback(SCNetworkReachabilityRef target, SCNetworkReachabilityFlags flags, void* info) |
{ |
#pragma unused (target, flags) |
NSCAssert(info != NULL, @"info was NULL in ReachabilityCallback"); |
NSCAssert([(__bridge NSObject*) info isKindOfClass: [Reachability class]], @"info was wrong class in ReachabilityCallback"); |
Reachability* noteObject = (__bridge Reachability *)info; |
// Post a notification to notify the client that the network reachability changed. |
[[NSNotificationCenter defaultCenter] postNotificationName: kReachabilityChangedNotification object: noteObject]; |
} |
#pragma mark - Reachability implementation |
@implementation Reachability |
{ |
SCNetworkReachabilityRef _reachabilityRef; |
} |
+ (instancetype)reachabilityWithHostName:(NSString *)hostName |
{ |
Reachability* returnValue = NULL; |
SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithName(NULL, [hostName UTF8String]); |
if (reachability != NULL) |
{ |
returnValue= [[self alloc] init]; |
if (returnValue != NULL) |
{ |
returnValue->_reachabilityRef = reachability; |
} |
else { |
CFRelease(reachability); |
} |
} |
return returnValue; |
} |
+ (instancetype)reachabilityWithAddress:(const struct sockaddr *)hostAddress |
{ |
SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, hostAddress); |
Reachability* returnValue = NULL; |
if (reachability != NULL) |
{ |
returnValue = [[self alloc] init]; |
if (returnValue != NULL) |
{ |
returnValue->_reachabilityRef = reachability; |
} |
else { |
CFRelease(reachability); |
} |
} |
return returnValue; |
} |
+ (instancetype)reachabilityForInternetConnection |
{ |
struct sockaddr_in zeroAddress; |
bzero(&zeroAddress, sizeof(zeroAddress)); |
zeroAddress.sin_len = sizeof(zeroAddress); |
zeroAddress.sin_family = AF_INET; |
return [self reachabilityWithAddress: (const struct sockaddr *) &zeroAddress]; |
} |
#pragma mark reachabilityForLocalWiFi |
//reachabilityForLocalWiFi has been removed from the sample. See ReadMe.md for more information. |
//+ (instancetype)reachabilityForLocalWiFi |
#pragma mark - Start and stop notifier |
- (BOOL)startNotifier |
{ |
BOOL returnValue = NO; |
SCNetworkReachabilityContext context = {0, (__bridge void *)(self), NULL, NULL, NULL}; |
if (SCNetworkReachabilitySetCallback(_reachabilityRef, ReachabilityCallback, &context)) |
{ |
if (SCNetworkReachabilityScheduleWithRunLoop(_reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode)) |
{ |
returnValue = YES; |
} |
} |
return returnValue; |
} |
- (void)stopNotifier |
{ |
if (_reachabilityRef != NULL) |
{ |
SCNetworkReachabilityUnscheduleFromRunLoop(_reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode); |
} |
} |
- (void)dealloc |
{ |
[self stopNotifier]; |
if (_reachabilityRef != NULL) |
{ |
CFRelease(_reachabilityRef); |
} |
} |
#pragma mark - Network Flag Handling |
- (NetworkStatus)networkStatusForFlags:(SCNetworkReachabilityFlags)flags |
{ |
PrintReachabilityFlags(flags, "networkStatusForFlags"); |
if ((flags & kSCNetworkReachabilityFlagsReachable) == 0) |
{ |
// The target host is not reachable. |
return NotReachable; |
} |
NetworkStatus returnValue = NotReachable; |
if ((flags & kSCNetworkReachabilityFlagsConnectionRequired) == 0) |
{ |
/* |
If the target host is reachable and no connection is required then we'll assume (for now) that you're on Wi-Fi... |
*/ |
returnValue = ReachableViaWiFi; |
} |
if ((((flags & kSCNetworkReachabilityFlagsConnectionOnDemand ) != 0) || |
(flags & kSCNetworkReachabilityFlagsConnectionOnTraffic) != 0)) |
{ |
/* |
... and the connection is on-demand (or on-traffic) if the calling application is using the CFSocketStream or higher APIs... |
*/ |
if ((flags & kSCNetworkReachabilityFlagsInterventionRequired) == 0) |
{ |
/* |
... and no [user] intervention is needed... |
*/ |
returnValue = ReachableViaWiFi; |
} |
} |
if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN) |
{ |
/* |
... but WWAN connections are OK if the calling application is using the CFNetwork APIs. |
*/ |
returnValue = ReachableViaWWAN; |
} |
return returnValue; |
} |
- (BOOL)connectionRequired |
{ |
NSAssert(_reachabilityRef != NULL, @"connectionRequired called with NULL reachabilityRef"); |
SCNetworkReachabilityFlags flags; |
if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) |
{ |
return (flags & kSCNetworkReachabilityFlagsConnectionRequired); |
} |
return NO; |
} |
- (NetworkStatus)currentReachabilityStatus |
{ |
NSAssert(_reachabilityRef != NULL, @"currentNetworkStatus called with NULL SCNetworkReachabilityRef"); |
NetworkStatus returnValue = NotReachable; |
SCNetworkReachabilityFlags flags; |
if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) |
{ |
returnValue = [self networkStatusForFlags:flags]; |
} |
return returnValue; |
} |
@end |
Copyright © 2016 Apple Inc. All Rights Reserved. Terms of Use | Privacy Policy | Updated: 2016-05-05