@@ -56,36 +56,49 @@
 
 #import <ObjFW/macros.h>
 
 #define BUFFER_LENGTH 512
 
-OF_ASSUME_NONNULL_BEGIN
-
 @interface XMPPConnection ()
-- (void)XMPP_startStream;
-- (void)XMPP_handleStream: (OFXMLElement *)element;
-- (void)XMPP_handleTLS: (OFXMLElement *)element;
-- (void)XMPP_handleSASL: (OFXMLElement *)element;
-- (void)XMPP_handleStanza: (OFXMLElement *)element;
-- (void)XMPP_sendAuth: (OFString *)authName;
-- (void)XMPP_sendResourceBind;
-- (void)XMPP_sendStreamError: (OFString *)condition
-			text: (nullable OFString *)text;
-- (void)XMPP_handleIQ: (XMPPIQ *)IQ;
-- (void)XMPP_handleMessage: (XMPPMessage *)message;
-- (void)XMPP_handlePresence: (XMPPPresence *)presence;
-- (void)XMPP_handleFeatures: (OFXMLElement *)element;
-- (void)XMPP_handleResourceBindForConnection: (XMPPConnection *)connection
-					  IQ: (XMPPIQ *)IQ;
-- (void)XMPP_sendSession;
-- (void)XMPP_handleSessionForConnection: (XMPPConnection *)connection
-				     IQ: (XMPPIQ *)IQ;
-- (OFString *)XMPP_IDNAToASCII: (OFString *)domain;
-- (XMPPMulticastDelegate *)XMPP_delegates;
-@end
-
-OF_ASSUME_NONNULL_END
+- (void)xmpp_socketDidConnect: (OFTCPSocket *)socket
+		      context: (OFArray *)nextSRVRecords
+		    exception: (id)exception;
+- (void)xmpp_tryNextSRVRecord: (OFArray *)SRVRecords;
+-  (void)xmpp_resolver: (OFDNSResolver *)resolver
+  didResolveDomainName: (OFString *)domainName
+	 answerRecords: (OFDictionary *)answerRecords
+      authorityRecords: (OFDictionary *)authorityRecords
+     additionalRecords: (OFDictionary *)additionalRecords
+	       context: (OFString *)domainToASCII
+	     exception: (id)exception;
+-  (bool)xmpp_parseBuffer: (const void *)buffer
+		   length: (size_t)length;
+- (bool)xmpp_stream: (OFStream *)stream
+  didReadIntoBuffer: (char *)buffer
+	     length: (size_t)length
+	  exception: (OFException *)exception;
+- (void)xmpp_startStream;
+- (void)xmpp_handleStanza: (OFXMLElement *)element;
+- (void)xmpp_handleStream: (OFXMLElement *)element;
+- (void)xmpp_handleTLS: (OFXMLElement *)element;
+- (void)xmpp_handleSASL: (OFXMLElement *)element;
+- (void)xmpp_handleIQ: (XMPPIQ *)IQ;
+- (void)xmpp_handleMessage: (XMPPMessage *)message;
+- (void)xmpp_handlePresence: (XMPPPresence *)presence;
+- (void)xmpp_handleFeatures: (OFXMLElement *)element;
+- (void)xmpp_sendAuth: (OFString *)authName;
+- (void)xmpp_sendResourceBind;
+- (void)xmpp_sendStreamError: (OFString *)condition
+			text: (OFString *)text;
+- (void)xmpp_handleResourceBindForConnection: (XMPPConnection *)connection
+					  IQ: (XMPPIQ *)IQ;
+- (void)xmpp_sendSession;
+- (void)xmpp_handleSessionForConnection: (XMPPConnection *)connection
+				     IQ: (XMPPIQ *)IQ;
+- (OFString *)xmpp_IDNAToASCII: (OFString *)domain;
+- (XMPPMulticastDelegate *)xmpp_delegates;
+@end
 
 @implementation XMPPConnection
 @synthesize username = _username, resource = _resource, server = _server;
 @synthesize domain = _domain, password = _password, language = _language;
 @synthesize privateKeyFile = _privateKeyFile;
@@ -97,11 +110,11 @@
 + (instancetype)connection
 {
 	return [[[self alloc] init] autorelease];
 }
 
-- init
+- (instancetype)init
 {
 	self = [super init];
 
 	@try {
 		_port = 5222;
@@ -190,11 +203,11 @@
 - (void)setServer: (OFString *)server
 {
 	OFString *old = _server;
 
 	if (server != nil)
-		_server = [self XMPP_IDNAToASCII: server];
+		_server = [self xmpp_IDNAToASCII: server];
 	else
 		_server = nil;
 
 	[old release];
 }
@@ -219,11 +232,11 @@
 			_domain = [[OFString alloc] initWithUTF8String: srv];
 		} @finally {
 			free(srv);
 		}
 
-		_domainToASCII = [self XMPP_IDNAToASCII: _domain];
+		_domainToASCII = [self xmpp_IDNAToASCII: _domain];
 	} else {
 		_domain = nil;
 		_domainToASCII = nil;
 	}
 
@@ -255,19 +268,19 @@
 		_password = nil;
 
 	[old release];
 }
 
-- (void)XMPP_socketDidConnect: (OFTCPSocket *)socket
+- (void)xmpp_socketDidConnect: (OFTCPSocket *)socket
 		      context: (OFArray *)nextSRVRecords
 		    exception: (id)exception
 {
 	char *buffer;
 
 	if (exception != nil) {
 		if (nextSRVRecords != nil) {
-			[self XMPP_tryNextSRVRecord: nextSRVRecords];
+			[self xmpp_tryNextSRVRecord: nextSRVRecords];
 			return;
 		}
 
 		[_delegates
 		    broadcastSelector: @selector(connection:didThrowException:)
@@ -274,22 +287,22 @@
 			   withObject: self
 			   withObject: exception];
 		return;
 	}
 
-	[self XMPP_startStream];
+	[self xmpp_startStream];
 
 	buffer = [self allocMemoryWithSize: BUFFER_LENGTH];
 	[_socket asyncReadIntoBuffer: buffer
 			      length: BUFFER_LENGTH
 			      target: self
-			    selector: @selector(XMPP_stream:didReadIntoBuffer:
+			    selector: @selector(xmpp_stream:didReadIntoBuffer:
 					  length:exception:)
 			     context: nil];
 }
 
-- (void)XMPP_tryNextSRVRecord: (OFArray *)SRVRecords
+- (void)xmpp_tryNextSRVRecord: (OFArray *)SRVRecords
 {
 	OFSRVDNSResourceRecord *record = [SRVRecords objectAtIndex: 0];
 
 	SRVRecords = [SRVRecords objectsInRange:
 	    of_range(1, [SRVRecords count] - 1)];
@@ -297,16 +310,16 @@
 		SRVRecords = nil;
 
 	[_socket asyncConnectToHost: [record target]
 			       port: [record port]
 			     target: self
-			   selector: @selector(XMPP_socketDidConnect:
+			   selector: @selector(xmpp_socketDidConnect:
 					 context:exception:)
 			    context: SRVRecords];
 }
 
--  (void)XMPP_resolver: (OFDNSResolver *)resolver
+-  (void)xmpp_resolver: (OFDNSResolver *)resolver
   didResolveDomainName: (OFString *)domainName
 	 answerRecords: (OFDictionary *)answerRecords
       authorityRecords: (OFDictionary *)authorityRecords
      additionalRecords: (OFDictionary *)additionalRecords
 	       context: (OFString *)domainToASCII
@@ -333,17 +346,17 @@
 	if ([records count] == 0) {
 		/* Fall back to A / AAA record. */
 		[_socket asyncConnectToHost: domainToASCII
 				       port: _port
 				     target: self
-				   selector: @selector(XMPP_socketDidConnect:
+				   selector: @selector(xmpp_socketDidConnect:
 						 context:exception:)
 				    context: nil];
 		return;
 	}
 
-	[self XMPP_tryNextSRVRecord: records];
+	[self xmpp_tryNextSRVRecord: records];
 }
 
 - (void)asyncConnect
 {
 	void *pool = objc_autoreleasePoolPush();
@@ -355,27 +368,27 @@
 
 	if (_server != nil)
 		[_socket asyncConnectToHost: _server
 				       port: _port
 				     target: self
-				   selector: @selector(XMPP_socketDidConnect:
+				   selector: @selector(xmpp_socketDidConnect:
 						 context:exception:)
 				    context: nil];
 	else
 		[[OFThread DNSResolver]
 		    asyncResolveHost: _domainToASCII
 			      target: self
-			    selector: @selector(XMPP_resolver:
+			    selector: @selector(xmpp_resolver:
 					  didResolveDomainName:answerRecords:
 					  authorityRecords:additionalRecords:
 					  context:exception:)
 			     context: _domainToASCII];
 
 	objc_autoreleasePoolPop(pool);
 }
 
--  (bool)XMPP_parseBuffer: (const void *)buffer
+-  (bool)xmpp_parseBuffer: (const void *)buffer
 		   length: (size_t)length
 {
 	if ([_socket isAtEndOfStream]) {
 		[_delegates broadcastSelector: @selector(connectionWasClosed:)
 				   withObject: self];
@@ -384,11 +397,11 @@
 
 	@try {
 		[_parser parseBuffer: buffer
 			     length: length];
 	} @catch (OFMalformedXMLException *e) {
-		[self XMPP_sendStreamError: @"bad-format"
+		[self xmpp_sendStreamError: @"bad-format"
 				      text: nil];
 		[self close];
 		return false;
 	}
 
@@ -396,21 +409,21 @@
 }
 
 - (void)parseBuffer: (const void *)buffer
 	     length: (size_t)length
 {
-	[self XMPP_parseBuffer: buffer
+	[self xmpp_parseBuffer: buffer
 			length: length];
 
 	[_oldParser release];
 	[_oldElementBuilder release];
 
 	_oldParser = nil;
 	_oldElementBuilder = nil;
 }
 
-- (bool)XMPP_stream: (OFStream *)stream
+- (bool)xmpp_stream: (OFStream *)stream
   didReadIntoBuffer: (char *)buffer
 	     length: (size_t)length
 	  exception: (OFException *)exception
 {
 	if (exception != nil) {
@@ -421,11 +434,11 @@
 		[self close];
 		return false;
 	}
 
 	@try {
-		if (![self XMPP_parseBuffer: buffer
+		if (![self xmpp_parseBuffer: buffer
 				     length: length])
 			return false;
 	} @catch (id e) {
 		[_delegates broadcastSelector: @selector(connection:
 						   didThrowException:)
@@ -443,11 +456,11 @@
 		_oldElementBuilder = nil;
 
 		[_socket asyncReadIntoBuffer: buffer
 				      length: BUFFER_LENGTH
 				      target: self
-				    selector: @selector(XMPP_stream:
+				    selector: @selector(xmpp_stream:
 						  didReadIntoBuffer:length:
 						  exception:)
 				     context: nil];
 
 		return false;
@@ -581,31 +594,31 @@
 		[_socket close];
 		return;
 	}
 
 	if (![prefix isEqual: @"stream"]) {
-		[self XMPP_sendStreamError: @"bad-namespace-prefix"
+		[self xmpp_sendStreamError: @"bad-namespace-prefix"
 				      text: nil];
 		return;
 	}
 
 	if (![NS isEqual: XMPP_NS_STREAM]) {
-		[self XMPP_sendStreamError: @"invalid-namespace"
+		[self xmpp_sendStreamError: @"invalid-namespace"
 				      text: nil];
 		return;
 	}
 
 	for (OFXMLAttribute *attribute in attributes) {
 		if ([[attribute name] isEqual: @"from"] &&
 		    ![[attribute stringValue] isEqual: _domain]) {
-			[self XMPP_sendStreamError: @"invalid-from"
+			[self xmpp_sendStreamError: @"invalid-from"
 					      text: nil];
 			return;
 		}
 		if ([[attribute name] isEqual: @"version"] &&
 		    ![[attribute stringValue] isEqual: @"1.0"]) {
-			[self XMPP_sendStreamError: @"unsupported-version"
+			[self xmpp_sendStreamError: @"unsupported-version"
 					      text: nil];
 			return;
 		}
 	}
 
@@ -626,20 +639,20 @@
 	[_delegates broadcastSelector: @selector(connection:didReceiveElement:)
 			   withObject: self
 			   withObject: element];
 
 	if ([[element namespace] isEqual: XMPP_NS_CLIENT])
-		[self XMPP_handleStanza: element];
+		[self xmpp_handleStanza: element];
 
 	if ([[element namespace] isEqual: XMPP_NS_STREAM])
-		[self XMPP_handleStream: element];
+		[self xmpp_handleStream: element];
 
 	if ([[element namespace] isEqual: XMPP_NS_STARTTLS])
-		[self XMPP_handleTLS: element];
+		[self xmpp_handleTLS: element];
 
 	if ([[element namespace] isEqual: XMPP_NS_SASL])
-		[self XMPP_handleSASL: element];
+		[self xmpp_handleSASL: element];
 }
 
 - (void)elementBuilder: (OFXMLElementBuilder *)builder
   didNotExpectCloseTag: (OFString *)name
 		prefix: (OFString *)prefix
@@ -651,11 +664,11 @@
 	else {
 		[self close];
 	}
 }
 
-- (void)XMPP_startStream
+- (void)xmpp_startStream
 {
 	OFString *langString = @"";
 
 	/* Make sure we don't get any old events */
 	[_parser setDelegate: nil];
@@ -706,38 +719,38 @@
 	_streamOpen = _needsSession = _encrypted = false;
 	_supportsRosterVersioning = _supportsStreamManagement = false;
 	_lastID = 0;
 }
 
-- (void)XMPP_handleStanza: (OFXMLElement *)element
+- (void)xmpp_handleStanza: (OFXMLElement *)element
 {
 	if ([[element name] isEqual: @"iq"]) {
-		[self XMPP_handleIQ: [XMPPIQ stanzaWithElement: element]];
+		[self xmpp_handleIQ: [XMPPIQ stanzaWithElement: element]];
 		return;
 	}
 
 	if ([[element name] isEqual: @"message"]) {
-		[self XMPP_handleMessage:
+		[self xmpp_handleMessage:
 		    [XMPPMessage stanzaWithElement: element]];
 		return;
 	}
 
 	if ([[element name] isEqual: @"presence"]) {
-		[self XMPP_handlePresence:
+		[self xmpp_handlePresence:
 		    [XMPPPresence stanzaWithElement: element]];
 		return;
 	}
 
-	[self XMPP_sendStreamError: @"unsupported-stanza-type"
+	[self xmpp_sendStreamError: @"unsupported-stanza-type"
 			      text: nil];
 }
 
 
-- (void)XMPP_handleStream: (OFXMLElement *)element
+- (void)xmpp_handleStream: (OFXMLElement *)element
 {
 	if ([[element name] isEqual: @"features"]) {
-		[self XMPP_handleFeatures: element];
+		[self xmpp_handleFeatures: element];
 		return;
 	}
 
 	if ([[element name] isEqual: @"error"]) {
 		OFString *condition, *reason;
@@ -834,11 +847,11 @@
 	}
 
 	assert(0);
 }
 
-- (void)XMPP_handleTLS: (OFXMLElement *)element
+- (void)xmpp_handleTLS: (OFXMLElement *)element
 {
 	if ([[element name] isEqual: @"proceed"]) {
 		/* FIXME: Catch errors here */
 		SSLSocket *newSock;
 
@@ -863,11 +876,11 @@
 		[_delegates broadcastSelector: @selector(
 						   connectionDidUpgradeToTLS:)
 				   withObject: self];
 
 		/* Stream restart */
-		[self XMPP_startStream];
+		[self xmpp_startStream];
 
 		return;
 	}
 
 	if ([[element name] isEqual: @"failure"])
@@ -875,11 +888,11 @@
 		@throw [OFException exception];
 
 	assert(0);
 }
 
-- (void)XMPP_handleSASL: (OFXMLElement *)element
+- (void)xmpp_handleSASL: (OFXMLElement *)element
 {
 	if ([[element name] isEqual: @"challenge"]) {
 		OFXMLElement *responseTag;
 		OFData *challenge =
 		    [OFData dataWithBase64EncodedString: [element stringValue]];
@@ -906,11 +919,11 @@
 		[_delegates broadcastSelector: @selector(
 						   connectionWasAuthenticated:)
 				   withObject: self];
 
 		/* Stream restart */
-		[self XMPP_startStream];
+		[self xmpp_startStream];
 
 		return;
 	}
 
 	if ([[element name] isEqual: @"failure"]) {
@@ -921,11 +934,11 @@
 	}
 
 	assert(0);
 }
 
-- (void)XMPP_handleIQ: (XMPPIQ *)IQ
+- (void)xmpp_handleIQ: (XMPPIQ *)IQ
 {
 	bool handled = false;
 	XMPPCallback *callback;
 	OFString *key;
 
@@ -952,25 +965,25 @@
 		[self sendStanza: [IQ errorIQWithType: @"cancel"
 					    condition: @"service-unavailable"]];
 	}
 }
 
-- (void)XMPP_handleMessage: (XMPPMessage *)message
+- (void)xmpp_handleMessage: (XMPPMessage *)message
 {
 	[_delegates broadcastSelector: @selector(connection:didReceiveMessage:)
 			   withObject: self
 			   withObject: message];
 }
 
-- (void)XMPP_handlePresence: (XMPPPresence *)presence
+- (void)xmpp_handlePresence: (XMPPPresence *)presence
 {
 	[_delegates broadcastSelector: @selector(connection:didReceivePresence:)
 			   withObject: self
 			   withObject: presence];
 }
 
-- (void)XMPP_handleFeatures: (OFXMLElement *)element
+- (void)xmpp_handleFeatures: (OFXMLElement *)element
 {
 	OFXMLElement *startTLS = [element elementForName: @"starttls"
 					       namespace: XMPP_NS_STARTTLS];
 	OFXMLElement *bind = [element elementForName: @"bind"
 					   namespace: XMPP_NS_BIND];
@@ -998,21 +1011,17 @@
 	if ([element elementForName: @"sm"
 			  namespace: XMPP_NS_SM] != nil)
 		_supportsStreamManagement = true;
 
 	if (mechs != nil) {
-		OFEnumerator *enumerator;
-		OFXMLElement *mech;
-
-		enumerator = [[mechs children] objectEnumerator];
-		while ((mech = [enumerator nextObject]) != nil)
+		for (OFXMLElement *mech in [mechs children])
 			[mechanisms addObject: [mech stringValue]];
 
 		if (_privateKeyFile != nil && _certificateFile != nil &&
 		    [mechanisms containsObject: @"EXTERNAL"]) {
 			_authModule = [[XMPPEXTERNALAuth alloc] init];
-			[self XMPP_sendAuth: @"EXTERNAL"];
+			[self xmpp_sendAuth: @"EXTERNAL"];
 			return;
 		}
 
 		if ([mechanisms containsObject: @"SCRAM-SHA-1-PLUS"]) {
 			_authModule = [[XMPPSCRAMAuth alloc]
@@ -1019,11 +1028,11 @@
 			    initWithAuthcid: _username
 				   password: _password
 				 connection: self
 				       hash: [OFSHA1Hash class]
 			      plusAvailable: true];
-			[self XMPP_sendAuth: @"SCRAM-SHA-1-PLUS"];
+			[self xmpp_sendAuth: @"SCRAM-SHA-1-PLUS"];
 			return;
 		}
 
 		if ([mechanisms containsObject: @"SCRAM-SHA-1"]) {
 			_authModule = [[XMPPSCRAMAuth alloc]
@@ -1030,19 +1039,19 @@
 			    initWithAuthcid: _username
 				   password: _password
 				 connection: self
 				       hash: [OFSHA1Hash class]
 			      plusAvailable: false];
-			[self XMPP_sendAuth: @"SCRAM-SHA-1"];
+			[self xmpp_sendAuth: @"SCRAM-SHA-1"];
 			return;
 		}
 
 		if ([mechanisms containsObject: @"PLAIN"] && _encrypted) {
 			_authModule = [[XMPPPLAINAuth alloc]
 			    initWithAuthcid: _username
 				   password: _password];
-			[self XMPP_sendAuth: @"PLAIN"];
+			[self xmpp_sendAuth: @"PLAIN"];
 			return;
 		}
 
 		assert(0);
 	}
@@ -1050,18 +1059,18 @@
 	if (session != nil && [session elementForName: @"optional"
 					    namespace: XMPP_NS_SESSION] == nil)
 		_needsSession = true;
 
 	if (bind != nil) {
-		[self XMPP_sendResourceBind];
+		[self xmpp_sendResourceBind];
 		return;
 	}
 
 	assert(0);
 }
 
-- (void)XMPP_sendAuth: (OFString *)authName
+- (void)xmpp_sendAuth: (OFString *)authName
 {
 	OFXMLElement *authTag;
 	OFData *initialMessage = [_authModule initialMessage];
 
 	authTag = [OFXMLElement elementWithName: @"auth"
@@ -1077,11 +1086,11 @@
 	}
 
 	[self sendStanza: authTag];
 }
 
-- (void)XMPP_sendResourceBind
+- (void)xmpp_sendResourceBind
 {
 	XMPPIQ *IQ;
 	OFXMLElement *bind;
 
 	IQ = [XMPPIQ IQWithType: @"set"
@@ -1097,15 +1106,15 @@
 
 	[IQ addChild: bind];
 
 	[self	    sendIQ: IQ
 	    callbackTarget: self
-		  selector: @selector(XMPP_handleResourceBindForConnection:
+		  selector: @selector(xmpp_handleResourceBindForConnection:
 				IQ:)];
 }
 
-- (void)XMPP_sendStreamError: (OFString *)condition
+- (void)xmpp_sendStreamError: (OFString *)condition
 			text: (OFString *)text
 {
 	OFXMLElement *error = [OFXMLElement
 	    elementWithName: @"error"
 		  namespace: XMPP_NS_STREAM];
@@ -1121,11 +1130,11 @@
 	[_parser setDelegate: nil];
 	[self sendStanza: error];
 	[self close];
 }
 
-- (void)XMPP_handleResourceBindForConnection: (XMPPConnection *)connection
+- (void)xmpp_handleResourceBindForConnection: (XMPPConnection *)connection
 					  IQ: (XMPPIQ *)IQ
 {
 	OFXMLElement *bindElement, *JIDElement;
 
 	assert([[IQ type] isEqual: @"result"]);
@@ -1138,33 +1147,33 @@
 	JIDElement = [bindElement elementForName: @"jid"
 				       namespace: XMPP_NS_BIND];
 	_JID = [[XMPPJID alloc] initWithString: [JIDElement stringValue]];
 
 	if (_needsSession) {
-		[self XMPP_sendSession];
+		[self xmpp_sendSession];
 		return;
 	}
 
 	[_delegates broadcastSelector: @selector(connection:wasBoundToJID:)
 			   withObject: self
 			   withObject: _JID];
 }
 
-- (void)XMPP_sendSession
+- (void)xmpp_sendSession
 {
 	XMPPIQ *IQ = [XMPPIQ IQWithType: @"set"
 				     ID: [self generateStanzaID]];
 
 	[IQ addChild: [OFXMLElement elementWithName: @"session"
 					  namespace: XMPP_NS_SESSION]];
 
 	[self	    sendIQ: IQ
 	    callbackTarget: self
-		  selector: @selector(XMPP_handleSessionForConnection:IQ:)];
+		  selector: @selector(xmpp_handleSessionForConnection:IQ:)];
 }
 
-- (void)XMPP_handleSessionForConnection: (XMPPConnection *)connection
+- (void)xmpp_handleSessionForConnection: (XMPPConnection *)connection
 				     IQ: (XMPPIQ *)IQ
 {
 	if (![[IQ type] isEqual: @"result"])
 		OF_ENSURE(0);
 
@@ -1171,11 +1180,11 @@
 	[_delegates broadcastSelector: @selector(connection:wasBoundToJID:)
 			   withObject: self
 			   withObject: _JID];
 }
 
-- (OFString *)XMPP_IDNAToASCII: (OFString *)domain
+- (OFString *)xmpp_IDNAToASCII: (OFString *)domain
 {
 	OFString *ret;
 	char *cDomain;
 	Idna_rc rc;
 
@@ -1217,10 +1226,10 @@
 - (void)removeDelegate: (id <XMPPConnectionDelegate>)delegate
 {
 	[_delegates removeDelegate: delegate];
 }
 
-- (XMPPMulticastDelegate *)XMPP_delegates
+- (XMPPMulticastDelegate *)xmpp_delegates
 {
 	return _delegates;
 }
 @end