ObjFW  Check-in [7ba597c52d]

 * @param host The host to resolve
 * @param target The target to call with the result once resolving is done
 * @param selector The selector to call on the target. The signature must be
 *		   the following:
 *		   @parblock
 *
 *		       void (OFDNSResolver *resolver, OFString *domainName,
 *		           OFArray<OFDictionary<OFString *,
 *		           __kindof OFDNSResourceRecord *> *>
 *		           *_Nullable answerRecords,
 *		           OFArray<OFDictionary<OFString *,
 *		           __kindof OFDNSResourceRecord *> *>
 *		           *_Nullable authorityRecords,
 *		           OFArray<OFDictionary<OFString *,
 *		           __kindof OFDNSResourceRecord *> *>
 *		           *_Nullable additionalRecords,
 *		           id _Nullable context, id _Nullable exception)
 *
 *		   `resolver` is the acting resolver.@n
 *		   `domainName` is the fully qualified domain name used to
 *		   resolve the host.@n
 *		   `answerRecords` are the answer records from the name server,
 *		   grouped by domain name.
 *		   @n
 *		   `authorityRecords` are the authority records from the name
 *		   server, grouped by domain name.@n
 *		   `additionalRecords` are additional records sent by the name
 *		   server, grouped by domain name.@n
 *		   `context` is the context object originally passed.@n
 *		   `exception` is an exception that happened during resolving,
 *		   otherwise nil.
 *		   @endparblock
 * @param context A context object to pass along to the target
 */
- (void)asyncResolveHost: (OFString *)host

 * @param recordType The desired type of the records to query
 * @param target The target to call with the result once resolving is done
 * @param selector The selector to call on the target. The signature must be
 *		   the following:
 *		   @parblock
 *
 *		       void (OFDNSResolver *resolver, OFString *domainName,
 *		           OFArray<OFDictionary<OFString *,
 *		           __kindof OFDNSResourceRecord *> *>
 *		           *_Nullable answerRecords,
 *		           OFArray<OFDictionary<OFString *,
 *		           __kindof OFDNSResourceRecord *> *>
 *		           *_Nullable authorityRecords,
 *		           OFArray<OFDictionary<OFString *,
 *		           __kindof OFDNSResourceRecord *> *>
 *		           *_Nullable additionalRecords,
 *		           id _Nullable context, id _Nullable exception)
 *
 *		   `resolver` is the acting resolver.@n
 *		   `domainName` is the fully qualified domain name used to
 *		   resolve the host.@n
 *		   `answerRecords` are the answer records from the name server,
 *		   grouped by domain name.
 *		   @n
 *		   `authorityRecords` are the authority records from the name
 *		   server, grouped by domain name.@n
 *		   `additionalRecords` are additional records sent by the name
 *		   server, grouped by domain name.@n
 *		   `context` is the context object originally passed.@n
 *		   `exception` is an exception that happened during resolving,
 *		   otherwise nil.
 *		   @endparblock
 * @param context A context object to pass along to the target
 */
- (void)asyncResolveHost: (OFString *)host

- (instancetype)initWithHost: (OFString *)host
		      target: (id)target
		    selector: (SEL)selector
		     context: (id)context;
-	(void)resolver: (OFDNSResolver *)resolver
  didResolveDomainName: (OFString *)domainName
	 answerRecords: (OFDictionary *)answerRecords
      authorityRecords: (OFDictionary *)authorityRecords
     additionalRecords: (OFDictionary *)additionalRecords
	       context: (id)context
	     exception: (id)exception;
@end

@interface OFDNSResolver ()
- (void)of_setDefaults;
- (void)of_obtainSystemConfig;

		return [[[OFDNSResourceRecord alloc]
		    initWithName: name
		     recordClass: recordClass
		      recordType: recordType
			     TTL: TTL] autorelease];
}

static OFDictionary *
parseSection(const unsigned char *buffer, size_t length, size_t *i,
    uint_fast16_t count)
{
	OFMutableDictionary *ret = [OFMutableDictionary dictionary];
	OFEnumerator OF_GENERIC(OFMutableArray *) *objectEnumerator;
	OFMutableArray *array;

	for (uint_fast16_t j = 0; j < count; j++) {
		OFString *name = parseName(buffer, length, i,
		    MAX_ALLOWED_POINTERS);
		of_dns_resource_record_class_t recordClass;
		of_dns_resource_record_type_t recordType;
		uint32_t TTL;

		if (*i + dataLength > length)
			@throw [OFTruncatedDataException exception];

		record = parseResourceRecord(name, recordClass, recordType, TTL,
		    buffer, length, *i, dataLength);
		*i += dataLength;

		array = [ret objectForKey: name];

		if (array == nil) {
			array = [OFMutableArray array];
			[ret setObject: array
				forKey: name];
		}

		[array addObject: record];
	}

	objectEnumerator = [ret objectEnumerator];
	while ((array = [objectEnumerator nextObject]) != nil)
		[array makeImmutable];

	[ret makeImmutable];

	return ret;
}

static void callback(id target, SEL selector, OFDNSResolver *resolver,
    OFString *domainName, OFDictionary *answerRecords,
    OFDictionary *authorityRecords, OFDictionary *additionalRecords, id context,
    id exception)
{
	void (*method)(id, SEL, OFDNSResolver *, OFString *, OFDictionary *,
	    OFDictionary *, OFDictionary *, id, id) = (void (*)(id, SEL,
	    OFDNSResolver *, OFString *, OFDictionary *, OFDictionary *,
	    OFDictionary *, id, id))[target methodForSelector: selector];

	method(target, selector, resolver, domainName, answerRecords,
	    authorityRecords, additionalRecords, context, exception);
}

@implementation OFDNSResolverSettings
- (instancetype)initWithNameServers: (OFArray *)nameServers

	[_records release];

	[super dealloc];
}

-	(void)resolver: (OFDNSResolver *)resolver
  didResolveDomainName: (OFString *)domainName
	 answerRecords: (OFDictionary *)answerRecords
      authorityRecords: (OFDictionary *)authorityRecords
     additionalRecords: (OFDictionary *)additionalRecords
	       context: (id)context
	     exception: (id)exception
{
	/*
	 * TODO: Error handling could be improved. Ignore error if there are
	 * responses, otherwise propagate error.
	 */

	of_socket_address_family_t addressFamily = [context intValue];

	_expectedResponses--;

	if (exception == nil) {
		for (OFDNSResourceRecord *record in
		    [answerRecords objectForKey: domainName]) {


			if ([record recordClass] !=
			    OF_DNS_RESOURCE_RECORD_CLASS_IN)
				continue;

			switch ([record recordType]) {
			case OF_DNS_RESOURCE_RECORD_TYPE_A:
				if (addressFamily ==

-      (bool)of_socket: (OFUDPSocket *)sock
  didReceiveIntoBuffer: (unsigned char *)buffer
		length: (size_t)length
		sender: (of_socket_address_t)sender
	       context: (id)context
	     exception: (id)exception
{
	OFDictionary *answerRecords = nil, *authorityRecords = nil;
	OFDictionary *additionalRecords = nil;
	OFNumber *ID;
	OFDNSResolverQuery *query;

	if (exception != nil) {
		if ([exception respondsToSelector: @selector(errNo)])
			return ([exception errNo] == EINTR);