From 95442be7b30bba2dce13e2fc38af5004dd1a4de2 Mon Sep 17 00:00:00 2001
From: Mattt Thompson <m@mattt.me>
Date: Tue, 10 Jan 2012 12:20:30 -0800
Subject: [PATCH] Initial implementation of network reachability callbacks

---
 AFNetworking/AFHTTPClient.h | 19 +++++++++++++++--
 AFNetworking/AFHTTPClient.m | 42 +++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/AFNetworking/AFHTTPClient.h b/AFNetworking/AFHTTPClient.h
index cb560f4..13c4782 100644
--- a/AFNetworking/AFHTTPClient.h
+++ b/AFNetworking/AFHTTPClient.h
@@ -35,6 +35,13 @@ typedef enum {
     AFPropertyListParameterEncoding,
 } AFHTTPClientParameterEncoding;
 
+/**
+ */
+typedef enum {
+    AFNetworkNotReachable,
+    AFNetworkReachable,
+} AFNetworkReachabilityStatus;
+
 /**
  Returns a string, replacing certain characters with the equivalent percent escape sequence based on the specified encoding.
  
@@ -157,9 +164,17 @@ extern NSString * AFQueryStringFromParametersWithEncoding(NSDictionary *paramete
  */
 - (id)initWithBaseURL:(NSURL *)url;
 
-///----------------------------------
+///-----------------------------------
+/// @name Managing Reachability Status
+///-----------------------------------
+
+/**
+ */
+- (void)setReachabilityStatusChangeBlock:(void (^)(AFNetworkReachabilityStatus reachabilityStatus))block;
+
+///-------------------------------
 /// @name Managing HTTP Operations
-///----------------------------------
+///-------------------------------
 
 /**
  Attempts to register a subclass of `AFHTTPRequestOperation`, adding it to a chain to automatically generate request operations from a URL request.
diff --git a/AFNetworking/AFHTTPClient.m b/AFNetworking/AFHTTPClient.m
index a48ae00..768fa50 100644
--- a/AFNetworking/AFHTTPClient.m
+++ b/AFNetworking/AFHTTPClient.m
@@ -27,6 +27,7 @@
 #import "AFJSONUtilities.h"
 
 #import <Availability.h>
+#import <SystemConfiguration/SystemConfiguration.h>
 
 #if __IPHONE_OS_VERSION_MIN_REQUIRED
 #import <UIKit/UIKit.h>
@@ -49,6 +50,16 @@ static NSString * const kAFMultipartFormBoundary = @"Boundary+0xAbCdEfGbOuNdArY"
 
 #pragma mark -
 
+typedef void (^AFNetworkReachabilityStatusBlock)(AFNetworkReachabilityStatus reachabilityStatus);
+
+static AFNetworkReachabilityStatus AFNetworkReachabilityStatusFromFlags(SCNetworkReachabilityFlags flags) {
+    if ((flags & kSCNetworkReachabilityFlagsReachable) == 0) {
+		return AFNetworkNotReachable;
+	} else {
+        return AFNetworkReachable;
+    }
+}
+
 static NSUInteger const kAFHTTPClientDefaultMaxConcurrentOperationCount = 4;
 
 static NSString * AFBase64EncodedStringFromString(NSString *string) {
@@ -124,6 +135,8 @@ static NSString * AFPropertyListStringFromParameters(NSDictionary *parameters) {
 @property (readwrite, nonatomic, retain) NSMutableArray *registeredHTTPOperationClassNames;
 @property (readwrite, nonatomic, retain) NSMutableDictionary *defaultHeaders;
 @property (readwrite, nonatomic, retain) NSOperationQueue *operationQueue;
+@property (readwrite, nonatomic, assign) SCNetworkReachabilityRef networkReachability;
+@property (readwrite, nonatomic, copy) AFNetworkReachabilityStatusBlock networkReachabilityStatusBlock;
 @end
 
 @implementation AFHTTPClient
@@ -133,6 +146,8 @@ static NSString * AFPropertyListStringFromParameters(NSDictionary *parameters) {
 @synthesize registeredHTTPOperationClassNames = _registeredHTTPOperationClassNames;
 @synthesize defaultHeaders = _defaultHeaders;
 @synthesize operationQueue = _operationQueue;
+@synthesize networkReachability = _networkReachability;
+@synthesize networkReachabilityStatusBlock = _networkReachabilityStatusBlock;
 
 + (AFHTTPClient *)clientWithBaseURL:(NSURL *)url {
     return [[[self alloc] initWithBaseURL:url] autorelease];
@@ -178,11 +193,38 @@ static NSString * AFPropertyListStringFromParameters(NSDictionary *parameters) {
     [_registeredHTTPOperationClassNames release];
     [_defaultHeaders release];
     [_operationQueue release];
+    [_networkReachabilityStatusBlock release];
+    if (_networkReachability) {
+        CFRelease(_networkReachability);
+    }
+    
     [super dealloc];
 }
 
 #pragma mark -
 
+static void AFReachabilityCallback(SCNetworkReachabilityRef __unused target, SCNetworkReachabilityFlags flags, void *info) {
+    if (info) {
+        AFNetworkReachabilityStatusBlock block = (AFNetworkReachabilityStatusBlock)info;
+        block(AFNetworkReachabilityStatusFromFlags(flags));
+    }
+}
+
+- (void)setReachabilityStatusChangeBlock:(void (^)(AFNetworkReachabilityStatus reachabilityStatus))block {
+    if (_networkReachability) {
+        SCNetworkReachabilityUnscheduleFromRunLoop(_networkReachability, CFRunLoopGetMain(), (CFStringRef)NSRunLoopCommonModes);
+        CFRelease(_networkReachability);
+    }
+    
+    self.networkReachabilityStatusBlock = block;
+    self.networkReachability = SCNetworkReachabilityCreateWithName(kCFAllocatorDefault, [[self.baseURL host] UTF8String]);
+    SCNetworkReachabilityContext context = {0, self.networkReachabilityStatusBlock, NULL, NULL, NULL};
+    SCNetworkReachabilitySetCallback(self.networkReachability, AFReachabilityCallback, &context);
+    SCNetworkReachabilityScheduleWithRunLoop(self.networkReachability, CFRunLoopGetMain(), (CFStringRef)NSRunLoopCommonModes);
+}
+
+#pragma mark -
+
 - (BOOL)registerHTTPOperationClass:(Class)operationClass {
     if (![operationClass isSubclassOfClass:[AFHTTPRequestOperation class]]) {
         return NO;