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Forked from dhoerl/Reachability.h
Created August 30, 2011 23:16
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Reachability (iOS) ARCified
/*
File: Reachability.h
Abstract: Basic demonstration of how to use the SystemConfiguration Reachablity APIs.
Version: 2.2 - ARCified
Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Inc.
("Apple") in consideration of your agreement to the following terms, and your
use, installation, modification or redistribution of this Apple software
constitutes acceptance of these terms. If you do not agree with these terms,
please do not use, install, modify or redistribute this Apple software.
In consideration of your agreement to abide by the following terms, and subject
to these terms, Apple grants you a personal, non-exclusive license, under
Apple's copyrights in this original Apple software (the "Apple Software"), to
use, reproduce, modify and redistribute the Apple Software, with or without
modifications, in source and/or binary forms; provided that if you redistribute
the Apple Software in its entirety and without modifications, you must retain
this notice and the following text and disclaimers in all such redistributions
of the Apple Software.
Neither the name, trademarks, service marks or logos of Apple Inc. may be used
to endorse or promote products derived from the Apple Software without specific
prior written permission from Apple. Except as expressly stated in this notice,
no other rights or licenses, express or implied, are granted by Apple herein,
including but not limited to any patent rights that may be infringed by your
derivative works or by other works in which the Apple Software may be
incorporated.
The Apple Software is provided by Apple on an "AS IS" basis. APPLE MAKES NO
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
COMBINATION WITH YOUR PRODUCTS.
IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR
DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF
CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF
APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Copyright (C) 2010 Apple Inc. All Rights Reserved.
*/
#import <Foundation/Foundation.h>
#import <SystemConfiguration/SystemConfiguration.h>
struct sockaddr_in;
typedef enum {
NotReachable = 0,
ReachableViaWiFi,
ReachableViaWWAN
} NetworkStatus;
#define kReachabilityChangedNotification @"kNetworkReachabilityChangedNotification"
@interface Reachability: NSObject
//reachabilityWithHostName- Use to check the reachability of a particular host name.
+ (Reachability*) reachabilityWithHostName: (NSString*) hostName;
//reachabilityWithAddress- Use to check the reachability of a particular IP address.
+ (Reachability*) reachabilityWithAddress: (const struct sockaddr_in*) hostAddress;
//reachabilityForInternetConnection- checks whether the default route is available.
// Should be used by applications that do not connect to a particular host
+ (Reachability*) reachabilityForInternetConnection;
//reachabilityForLocalWiFi- checks whether a local wifi connection is available.
+ (Reachability*) reachabilityForLocalWiFi;
//Start listening for reachability notifications on the current run loop
- (BOOL) startNotifier;
- (void) stopNotifier;
- (NetworkStatus) currentReachabilityStatus;
//WWAN may be available, but not active until a connection has been established.
//WiFi may require a connection for VPN on Demand.
- (BOOL) connectionRequired;
@end
/*
File: Reachability.m
Abstract: Basic demonstration of how to use the SystemConfiguration Reachablity APIs.
Version: 2.2 - ARCified
Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Inc.
("Apple") in consideration of your agreement to the following terms, and your
use, installation, modification or redistribution of this Apple software
constitutes acceptance of these terms. If you do not agree with these terms,
please do not use, install, modify or redistribute this Apple software.
In consideration of your agreement to abide by the following terms, and subject
to these terms, Apple grants you a personal, non-exclusive license, under
Apple's copyrights in this original Apple software (the "Apple Software"), to
use, reproduce, modify and redistribute the Apple Software, with or without
modifications, in source and/or binary forms; provided that if you redistribute
the Apple Software in its entirety and without modifications, you must retain
this notice and the following text and disclaimers in all such redistributions
of the Apple Software.
Neither the name, trademarks, service marks or logos of Apple Inc. may be used
to endorse or promote products derived from the Apple Software without specific
prior written permission from Apple. Except as expressly stated in this notice,
no other rights or licenses, express or implied, are granted by Apple herein,
including but not limited to any patent rights that may be infringed by your
derivative works or by other works in which the Apple Software may be
incorporated.
The Apple Software is provided by Apple on an "AS IS" basis. APPLE MAKES NO
WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN
COMBINATION WITH YOUR PRODUCTS.
IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, MODIFICATION AND/OR
DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED AND WHETHER UNDER THEORY OF
CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY OR OTHERWISE, EVEN IF
APPLE HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Copyright (C) 2010 Apple Inc. All Rights Reserved.
*/
#import <sys/socket.h>
#import <netinet/in.h>
#import <netinet6/in6.h>
#import <arpa/inet.h>
#import <ifaddrs.h>
#import <netdb.h>
#import <CoreFoundation/CoreFoundation.h>
#import "Reachability.h"
//#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");
//We're on the main RunLoop, so an NSAutoreleasePool is not necessary, but is added defensively
// in case someon uses the Reachablity object in a different thread.
@autoreleasepool {
Reachability* noteObject = (__bridge Reachability*) info;
// Post a notification to notify the client that the network reachability changed.
[[NSNotificationCenter defaultCenter] postNotificationName: kReachabilityChangedNotification object: noteObject];
}
}
@implementation Reachability
{
BOOL localWiFiRef;
SCNetworkReachabilityRef reachabilityRef;
}
- (BOOL)startNotifier
{
BOOL retVal = NO;
SCNetworkReachabilityContext context = {0, (__bridge void *)self, NULL, NULL, NULL};
if(SCNetworkReachabilitySetCallback(reachabilityRef, ReachabilityCallback, &context))
{
if(SCNetworkReachabilityScheduleWithRunLoop(reachabilityRef, CFRunLoopGetMain(), kCFRunLoopDefaultMode)) // DFH CFRunLoopGetCurrent()
{
retVal = YES;
}
}
return retVal;
}
- (void)stopNotifier
{
if(reachabilityRef != NULL)
{
SCNetworkReachabilityUnscheduleFromRunLoop(reachabilityRef, CFRunLoopGetMain(), kCFRunLoopDefaultMode); // CFRunLoopGetCurrent()
}
}
- (void) dealloc
{
[self stopNotifier];
if(reachabilityRef!= NULL)
{
CFRelease(reachabilityRef);
}
}
+ (Reachability*)reachabilityWithHostName: (NSString*) hostName;
{
Reachability* retVal = NULL;
SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithName(NULL, [hostName UTF8String]);
if(reachability!= NULL)
{
retVal= [[self alloc] init];
if(retVal!= NULL)
{
retVal->reachabilityRef = reachability;
retVal->localWiFiRef = NO;
}
}
return retVal;
}
+ (Reachability*) reachabilityWithAddress: (const struct sockaddr_in*) hostAddress;
{
SCNetworkReachabilityRef reachability = SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, (const struct sockaddr*)hostAddress);
Reachability* retVal = NULL;
if(reachability!= NULL)
{
retVal= [[self alloc] init];
if(retVal!= NULL)
{
retVal->reachabilityRef = reachability;
retVal->localWiFiRef = NO;
}
}
return retVal;
}
+ (Reachability*) reachabilityForInternetConnection;
{
struct sockaddr_in zeroAddress;
bzero(&zeroAddress, sizeof(zeroAddress));
zeroAddress.sin_len = sizeof(zeroAddress);
zeroAddress.sin_family = AF_INET;
return [self reachabilityWithAddress: &zeroAddress];
}
+ (Reachability*) reachabilityForLocalWiFi;
{
struct sockaddr_in localWifiAddress;
bzero(&localWifiAddress, sizeof(localWifiAddress));
localWifiAddress.sin_len = sizeof(localWifiAddress);
localWifiAddress.sin_family = AF_INET;
// IN_LINKLOCALNETNUM is defined in <netinet/in.h> as 169.254.0.0
localWifiAddress.sin_addr.s_addr = htonl(IN_LINKLOCALNETNUM);
Reachability* retVal = [self reachabilityWithAddress: &localWifiAddress];
if(retVal!= NULL)
{
retVal->localWiFiRef = YES;
}
return retVal;
}
#pragma mark Network Flag Handling
- (NetworkStatus) localWiFiStatusForFlags: (SCNetworkReachabilityFlags) flags
{
PrintReachabilityFlags(flags, "localWiFiStatusForFlags");
BOOL retVal = NotReachable;
if((flags & kSCNetworkReachabilityFlagsReachable) && (flags & kSCNetworkReachabilityFlagsIsDirect))
{
retVal = ReachableViaWiFi;
}
return retVal;
}
- (NetworkStatus) networkStatusForFlags: (SCNetworkReachabilityFlags) flags
{
PrintReachabilityFlags(flags, "networkStatusForFlags");
if ((flags & kSCNetworkReachabilityFlagsReachable) == 0)
{
// if target host is not reachable
return NotReachable;
}
BOOL retVal = NotReachable;
if ((flags & kSCNetworkReachabilityFlagsConnectionRequired) == 0)
{
// if target host is reachable and no connection is required
// then we'll assume (for now) that your on Wi-Fi
retVal = 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
retVal = ReachableViaWiFi;
}
}
if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN)
{
// ... but WWAN connections are OK if the calling application
// is using the CFNetwork (CFSocketStream?) APIs.
retVal = ReachableViaWWAN;
}
return retVal;
}
- (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 reachabilityRef");
NetworkStatus retVal = NotReachable;
SCNetworkReachabilityFlags flags;
if (SCNetworkReachabilityGetFlags(reachabilityRef, &flags))
{
if(localWiFiRef)
{
retVal = [self localWiFiStatusForFlags: flags];
}
else
{
retVal = [self networkStatusForFlags: flags];
}
}
return retVal;
}
@end
@ukiino
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ukiino commented Apr 11, 2013

Thanks! Great!

@klairton
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Good Work!
Thanks!

@waseemsarwar
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Thanks, it saved time

@DEV-ANDROID-DC
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Thanks, It saved me.... ;)

@wuyahuang
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Thanks, It saved me.... ;)

@cohilla
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cohilla commented Nov 22, 2022

Has anyone encountered SIGPIPE terminations caused by this code?

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