add reachability support

BANetworkReachability.h

@@ -0,0 +1,74 @@
+/*
+ Copyright 2012 Dmitry Stadnik. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modification, are
+ permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice, this list of
+ conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ of conditions and the following disclaimer in the documentation and/or other materials
+ provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY DMITRY STADNIK ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DMITRY STADNIK OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ The views and conclusions contained in the software and documentation are those of the
+ authors and should not be interpreted as representing official policies, either expressed
+ or implied, of Dmitry Stadnik.
+ */
+
+// Based on Reachability sample project
+
+#import <Foundation/Foundation.h>
+#import <SystemConfiguration/SystemConfiguration.h>
+#import <netinet/in.h>
+
+extern NSString * const BANetworkReachabilityDidChangeNotification;
+
+typedef enum {
+	BANetworkNotReachable = 0,
+	BANetworkReachableViaWiFi,
+	BANetworkReachableViaWWAN
+} BANetworkStatus;
+
+@interface BANetworkReachability : NSObject
+
+// Use to check the reachability of a particular host name.
++ (BANetworkReachability *)reachabilityWithHostName:(NSString *)hostName;
+
+// Use to check the reachability of a particular IP address.
++ (BANetworkReachability *)reachabilityWithAddress:(const struct sockaddr_in *)hostAddress;
+
+// Checks whether the default route is available.
+// Should be used by applications that do not connect to a particular host.
++ (BANetworkReachability *)reachabilityForInternetConnection;
+
+// Checks whether a local wifi connection is available.
++ (BANetworkReachability *)reachabilityForLocalWiFi;
+
+// Start listening for reachability notifications on the current run loop.
+- (BOOL)start;
+
+// Stop listening for reachability notifications on the current run loop.
+- (void)stop;
+
+@property(nonatomic, readonly) BANetworkStatus currentStatus;
+
+// WWAN may be available, but not active until a connection has been established.
+// WiFi may require a connection for VPN on Demand.
+@property(nonatomic, readonly) BOOL connectionRequired;
+
+- (SCNetworkReachabilityFlags)flags;
+
+- (NSString *)flagsString;
+
+@end

BANetworkReachability.m

@@ -0,0 +1,202 @@
+/*
+ Copyright 2012 Dmitry Stadnik. All rights reserved.
+
+ Redistribution and use in source and binary forms, with or without modification, are
+ permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice, this list of
+ conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ of conditions and the following disclaimer in the documentation and/or other materials
+ provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY DMITRY STADNIK ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL DMITRY STADNIK OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ The views and conclusions contained in the software and documentation are those of the
+ authors and should not be interpreted as representing official policies, either expressed
+ or implied, of Dmitry Stadnik.
+ */
+
+#import "BANetworkReachability.h"
+#import <sys/socket.h>
+#import <netinet6/in6.h>
+#import <arpa/inet.h>
+#import <ifaddrs.h>
+#import <netdb.h>
+#import <CoreFoundation/CoreFoundation.h>
+
+NSString * const BANetworkReachabilityDidChangeNotification = @"BANetworkReachabilityDidChange";
+
+static void BANetworkReachabilityCallback(SCNetworkReachabilityRef target, SCNetworkReachabilityFlags flags, void *info) {
+	// We're on the main RunLoop, so an NSAutoreleasePool is not necessary, but is added defensively
+	// in case someone uses the BANetworkReachability object in a different thread.
+	NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
+	BANetworkReachability *reachability = (BANetworkReachability *)info;
+	[[NSNotificationCenter defaultCenter] postNotificationName:BANetworkReachabilityDidChangeNotification
+														object:reachability];
+	[pool release];
+}
+
+@implementation BANetworkReachability {
+	SCNetworkReachabilityRef _reachabilityRef;
+	BOOL _localWiFiRef;
+	BOOL _started;
+}
+
+- (void)dealloc {
+	[self stop];
+	if (_reachabilityRef) {
+		CFRelease(_reachabilityRef);
+	}
+	[super dealloc];
+}
+
+- (id)initWithRef:(SCNetworkReachabilityRef)reachabilityRef /*retained*/ localWiFi:(BOOL)localWiFiRef {
+	if ((self = [super init])) {
+		_reachabilityRef = reachabilityRef;
+		_localWiFiRef = localWiFiRef;
+	}
+	return self;
+}
+
++ (BANetworkReachability *)reachabilityWithHostName:(NSString *)hostName {
+	SCNetworkReachabilityRef reachabilityRef = SCNetworkReachabilityCreateWithName(NULL, [hostName UTF8String]);
+	return reachabilityRef ? [[[BANetworkReachability alloc] initWithRef:reachabilityRef localWiFi:NO] autorelease] : nil;
+}
+
++ (BANetworkReachability *)reachabilityWithAddress:(const struct sockaddr_in *)hostAddress {
+	SCNetworkReachabilityRef reachabilityRef = SCNetworkReachabilityCreateWithAddress(kCFAllocatorDefault, (const struct sockaddr *)hostAddress);
+	return reachabilityRef ? [[[BANetworkReachability alloc] initWithRef:reachabilityRef localWiFi:NO] autorelease] : nil;
+}
+
++ (BANetworkReachability *)reachabilityForInternetConnection {
+	struct sockaddr_in zeroAddress;
+	bzero(&zeroAddress, sizeof(zeroAddress));
+	zeroAddress.sin_len = sizeof(zeroAddress);
+	zeroAddress.sin_family = AF_INET;
+	return [self reachabilityWithAddress:&zeroAddress];
+}
+
++ (BANetworkReachability *)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);
+	BANetworkReachability *retVal = [self reachabilityWithAddress:&localWifiAddress];
+	if (retVal) {
+		retVal->_localWiFiRef = YES;
+	}
+	return retVal;
+}
+
+- (void)stop {
+	if (_reachabilityRef && _started) {
+		SCNetworkReachabilityUnscheduleFromRunLoop(_reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
+		_started = NO;
+	}
+}
+
+- (BOOL)start {
+	if (_started) {
+		return YES;
+	}
+	SCNetworkReachabilityContext context = {0, self, NULL, NULL, NULL};
+	return _started = SCNetworkReachabilitySetCallback(_reachabilityRef, BANetworkReachabilityCallback, &context) &&
+	SCNetworkReachabilityScheduleWithRunLoop(_reachabilityRef, CFRunLoopGetCurrent(), kCFRunLoopDefaultMode);
+}
+
+- (BANetworkStatus)currentStatus {
+	SCNetworkReachabilityFlags flags;
+	if (!SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) {
+		return BANetworkNotReachable;
+	}
+	return _localWiFiRef ? [self localWiFiStatusForFlags:flags] : [self networkStatusForFlags:flags];
+}
+
+- (BANetworkStatus)localWiFiStatusForFlags:(SCNetworkReachabilityFlags)flags {
+	BOOL retVal = BANetworkNotReachable;
+	if ((flags & kSCNetworkReachabilityFlagsReachable) &&
+		(flags & kSCNetworkReachabilityFlagsIsDirect))
+	{
+		retVal = BANetworkReachableViaWiFi;
+	}
+	return retVal;
+}
+
+- (BANetworkStatus)networkStatusForFlags:(SCNetworkReachabilityFlags)flags {
+	if ((flags & kSCNetworkReachabilityFlagsReachable) == 0) {
+		return BANetworkNotReachable;
+	}
+
+	BOOL retVal = BANetworkNotReachable;
+
+	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 = BANetworkReachableViaWiFi;
+	}
+
+	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 = BANetworkReachableViaWiFi;
+		}
+	}
+
+	if ((flags & kSCNetworkReachabilityFlagsIsWWAN) == kSCNetworkReachabilityFlagsIsWWAN) {
+		// ... but WWAN connections are OK if the calling application
+		// is using the CFNetwork (CFSocketStream?) APIs.
+		retVal = BANetworkReachableViaWWAN;
+	}
+	return retVal;
+}
+
+- (BOOL)connectionRequired; {
+	SCNetworkReachabilityFlags flags;
+	if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) {
+		return (flags & kSCNetworkReachabilityFlagsConnectionRequired);
+	}
+	return NO;
+}
+
+- (SCNetworkReachabilityFlags)flags {
+	SCNetworkReachabilityFlags flags;
+	if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) {
+		return flags;
+	}
+	return 0;
+}
+
+- (NSString *)flagsString {
+	SCNetworkReachabilityFlags flags;
+	if (SCNetworkReachabilityGetFlags(_reachabilityRef, &flags)) {
+		return [NSString stringWithFormat:@"%c%c %c%c%c%c%c%c%c",
+				(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' : '-'];
+	}
+	return @"";
+}
+
+@end

BaseAppKitCore.h

@@ -6,6 +6,7 @@
 #include <BaseAppKit/BANetworkActivity.h>
 #include <BaseAppKit/BAPersistentCache.h>
 #include <BaseAppKit/BANetwork.h>
+#include <BaseAppKit/BANetworkReachability.h>
 #include <BaseAppKit/BADataLoader.h>
 #include <BaseAppKit/BAJSONLoader.h>
 #include <BaseAppKit/BAXMLParserBase.h>