Updated SDNetTask.h/m to support new error types:

- SDNetTaskErrorAuthenticationCanceled
- SDNetTaskErrorAuthenticationFailed
- SDNetTaskErrorNotConnectedToInternet

For reasons I don't get, when authentication fails, the NSError's error
code is SDNetTaskErrorAuthenticationCanceled whenever I use an incorrect
password

Source/SDNetTask.h

@@ -19,6 +19,9 @@ typedef enum _SDNetTaskError {
 	SDNetTaskErrorParserFailed,
 	SDNetTaskErrorParserDataIsNil,
 	SDNetTaskErrorServiceDefinedError,
+	SDNetTaskErrorAuthenticationCanceled,
+	SDNetTaskErrorAuthenticationFailed,
+	SDNetTaskErrorNotConnectedToInternet,
 
 	SDNetTaskErrorMAX // once again, don't touch.
 } SDNetTaskError;

Source/SDNetTask.m

@@ -116,14 +116,25 @@ - (void) main {
 
 	if (connectionError) {
 		underlyingError = connectionError;
-
 		// commented out the next line because some APIs are using HTTP error codes as return values, which is super lame
 
 //		errorCode = SDNetTaskErrorConnectionFailed;
 //		[self _sendResultsToDelegate];
 //		return;
 	}
 
+	switch ([underlyingError code]) {
+		case NSURLErrorUserCancelledAuthentication:
+			errorCode = SDNetTaskErrorAuthenticationCanceled;
+			break;
+		case NSURLErrorUserAuthenticationRequired:
+			errorCode = SDNetTaskErrorAuthenticationFailed;
+			break;
+		case NSURLErrorNotConnectedToInternet:
+			errorCode = SDNetTaskErrorNotConnectedToInternet;
+			break;	
+	}
+
 	if (data == nil) {
 		errorCode = SDNetTaskErrorConnectionDataIsNil;
 		[self _sendResultsToDelegate];
@@ -151,6 +162,7 @@ - (void) main {
 		errorCode = SDNetTaskErrorParserFailed;
 		underlyingError = errorFromParser;
 	}
+
 	else if (results == nil)
 		errorCode = SDNetTaskErrorParserDataIsNil;
 
@@ -167,8 +179,7 @@ - (void) _sendResultsToDelegateFromMainThread {
 
 	if (errorCode == SDNetTaskErrorNone) {
 		[self sendResultsToDelegate];
-	}
-	else {
+	} else {
 		// we'll create our error manually and let the delegate get all touchy-feely with it all they want
 
 		NSMutableDictionary *userInfo = [NSMutableDictionary dictionary];
@@ -347,6 +358,10 @@ - (NSString*) errorString {
 	errorStrings[SDNetTaskErrorConnectionFailed] = @"Connection failed with error";
 	errorStrings[SDNetTaskErrorParserFailed] = @"Parser failed with error";
 	errorStrings[SDNetTaskErrorParserDataIsNil] = @"Parser returned NULL data";
+	errorStrings[SDNetTaskErrorAuthenticationCanceled] = @"Authentication request cancelled";
+	errorStrings[SDNetTaskErrorAuthenticationFailed] = @"Authentication failed";
+	errorStrings[SDNetTaskErrorNotConnectedToInternet] = @"No internet connection established";
+
 	return errorStrings[errorCode];
 }