UIDevice-Reachability.m

/*
 Erica Sadun, http://ericasadun.com
 iPhone Developer's Cookbook, 3.0 Edition
 BSD License for anything not specifically marked as developed by a third party.
 Apple's code excluded.
 Use at your own risk
 */

// TTD: Add async version of whatsmyip -- thanks rpetrich

#include <unistd.h>
#include <sys/sysctl.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <netinet/in.h>
#include <ifaddrs.h>

#import "UIDevice-Reachability.h"
#import "wwanconnect.h"

@implementation UIDevice (Reachability)

#pragma mark host and ip utils
- (NSString *) hostname
{
	char baseHostName[255];
	int success = gethostname(baseHostName, 255);
	if (success != 0) return nil;
	baseHostName[255] = '\0';
	
#if !TARGET_IPHONE_SIMULATOR
	return [NSString stringWithFormat:@"%s.local", baseHostName];
#else
	return [NSString stringWithFormat:@"%s", baseHostName];
#endif
}

// Direct from Apple. Thank you Apple
- (BOOL)addressFromString:(NSString *)IPAddress address:(struct sockaddr_in *)address
{
	if (!IPAddress || ![IPAddress length]) {
		return NO;
	}
	
	memset((char *) address, sizeof(struct sockaddr_in), 0);
	address->sin_family = AF_INET;
	address->sin_len = sizeof(struct sockaddr_in);
	
	int conversionResult = inet_aton([IPAddress UTF8String], &address->sin_addr);
	if (conversionResult == 0) {
		NSAssert1(conversionResult != 1, @"Failed to convert the IP address string into a sockaddr_in: %@", IPAddress);
		return NO;
	}
	
	return YES;
}

- (NSString *) getIPAddressForHost: (NSString *) theHost
{
	struct hostent *host = gethostbyname([theHost UTF8String]);
	
    if (host == NULL) {
        herror("resolv");
		return NULL;
	}
	
	struct in_addr **list = (struct in_addr **)host->h_addr_list;
	NSString *addressString = [NSString stringWithCString:inet_ntoa(*list[0])];
	return addressString;
}

#if ! defined(IFT_ETHER)
#define IFT_ETHER 0x6	// Ethernet CSMACD
#endif

// Matt Brown's get WiFi IP addy solution
// Author gave permission to use in Cookbook under cookbook license
// http://mattbsoftware.blogspot.com/2009/04/how-to-get-ip-address-of-iphone-os-v221.html
- (NSString *) localWiFiIPAddress
{
	BOOL success;
	struct ifaddrs * addrs;
	const struct ifaddrs * cursor;
	
	success = getifaddrs(&addrs) == 0;
	if (success) {
		cursor = addrs;
		while (cursor != NULL) {
			// the second test keeps from picking up the loopback address
			if (cursor->ifa_addr->sa_family == AF_INET && (cursor->ifa_flags & IFF_LOOPBACK) == 0) 
			{
				NSString *name = [NSString stringWithUTF8String:cursor->ifa_name];
				if ([name isEqualToString:@"en0"]) { // found the WiFi adapter
					return [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)cursor->ifa_addr)->sin_addr)];
				}
			}
			cursor = cursor->ifa_next;
		}
		freeifaddrs(addrs);
	}
	return nil;
}

// Return the local IP address
- (NSString *) localIPAddress
{
	struct hostent *host = gethostbyname([[self hostname] UTF8String]);
    if (host == NULL)
	{
        herror("resolv");
		return nil;
	}
    else {
        struct in_addr **list = (struct in_addr **)host->h_addr_list;
		return [NSString stringWithCString:inet_ntoa(*list[0])];
    }
	return nil;
}

- (NSString *) whatismyipdotcom
{
	NSError *error;
    NSURL *ipURL = [NSURL URLWithString:@"http://www.whatismyip.com/automation/n09230945.asp"];
    NSString *ip = [NSString stringWithContentsOfURL:ipURL encoding:1 error:&error];
	if (!ip) return [error localizedDescription];
	return ip;
}

- (BOOL) activeWLAN
{
	return ([self localWiFiIPAddress] != nil);
}

#pragma mark Forcing WWAN connection

MyStreamInfoPtr	myInfoPtr;

static void myClientCallback(void *refCon)
{
	int  *val = (int*)refCon;
	printf("myClientCallback entered - value from refCon is %d\n", *val);
}

- (BOOL) forceWWAN
{
	int value = 0;
	myInfoPtr = (MyStreamInfoPtr) StartWWAN(myClientCallback, &value);
	if (myInfoPtr)	
	{
		printf("Started WWAN\n");
		return YES;
	}
	printf("Failed to start WWAN\n");
	return NO;
}

- (void) shutdownWWAN
{
	if (myInfoPtr) StopWWAN((MyInfoRef) myInfoPtr);
}

@end

#if SUPPORTS_UNDOCUMENTED_API
@implementation UIDevice (UIDevice_Undocumented_Reachability)
- (BOOL) networkAvailable
{
	// Unavailable has only one address: 127.0.0.1
	return !(([[[NSHost currentHost] addresses] count] == 1) && [[self localIPAddress] isEqualToString:@"127.0.0.1"]);
}

- (BOOL) activeWWAN
{
	return ([self networkAvailable] && ![self localWiFiIPAddress]);
}
@end
#endif  // SUPPORTS_UNDOCUMENTED_API