ObjFW  Documentation

/*
 * Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
 *
 * All rights reserved.
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License version 3.0 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
 * version 3.0 for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 3.0 along with this program. If not, see
 * <https://www.gnu.org/licenses/>.
 */

#include "config.h"

#import "OFIRIHandler.h"
#import "OFDictionary.h"
#import "OFIRI.h"
#import "OFNumber.h"

#ifdef OF_HAVE_THREADS
# import "OFMutex.h"
#endif

#import "OFArchiveIRIHandler.h"
#import "OFEmbeddedIRIHandler.h"
#ifdef OF_HAVE_FILES
# import "OFFileIRIHandler.h"
#endif
#if defined(OF_HAVE_SOCKETS) && defined(OF_HAVE_THREADS)
# import "OFHTTPIRIHandler.h"
#endif

#import "OFUnsupportedProtocolException.h"

static OFMutableDictionary OF_GENERIC(OFString *, OFIRIHandler *) *handlers;
#ifdef OF_HAVE_THREADS
static OFMutex *mutex;

static void
releaseMutex(void)
{
	[mutex release];
}
#endif

@implementation OFIRIHandler
@synthesize scheme = _scheme;

+ (void)initialize
{
	if (self != [OFIRIHandler class])
		return;

	handlers = [[OFMutableDictionary alloc] init];
#ifdef OF_HAVE_THREADS
	mutex = [[OFMutex alloc] init];
	atexit(releaseMutex);
#endif

	[self registerClass: [OFEmbeddedIRIHandler class]
		  forScheme: @"embedded"];
#ifdef OF_HAVE_FILES
	[self registerClass: [OFFileIRIHandler class] forScheme: @"file"];
#endif
#if defined(OF_HAVE_SOCKETS) && defined(OF_HAVE_THREADS)
	[self registerClass: [OFHTTPIRIHandler class] forScheme: @"http"];
	[self registerClass: [OFHTTPIRIHandler class] forScheme: @"https"];
#endif
	[self registerClass: [OFArchiveIRIHandler class] forScheme: @"gzip"];
	[self registerClass: [OFArchiveIRIHandler class] forScheme: @"lha"];
	[self registerClass: [OFArchiveIRIHandler class] forScheme: @"tar"];
	[self registerClass: [OFArchiveIRIHandler class] forScheme: @"zip"];
	[self registerClass: [OFArchiveIRIHandler class] forScheme: @"zoo"];
}

+ (bool)registerClass: (Class)class forScheme: (OFString *)scheme
{
#ifdef OF_HAVE_THREADS
	[mutex lock];
	@try {
#endif
		OFIRIHandler *handler;

		if ([handlers objectForKey: scheme] != nil)
			return false;

		handler = [[class alloc] initWithScheme: scheme];
		@try {
			[handlers setObject: handler forKey: scheme];
		} @finally {
			[handler release];
		}
#ifdef OF_HAVE_THREADS
	} @finally {
		[mutex unlock];
	}
#endif

	return true;
}

+ (OFIRIHandler *)handlerForIRI: (OFIRI *)IRI
{
	OF_KINDOF(OFIRIHandler *) handler;

#ifdef OF_HAVE_THREADS
	[mutex lock];
	@try {
#endif
		handler = [handlers objectForKey: IRI.scheme];
#ifdef OF_HAVE_THREADS
	} @finally {
		[mutex unlock];
	}
#endif

	if (handler == nil)
		@throw [OFUnsupportedProtocolException exceptionWithIRI: IRI];

	return handler;
}

+ (OFStream *)openItemAtIRI: (OFIRI *)IRI mode: (OFString *)mode
{
	return [[self handlerForIRI: IRI] openItemAtIRI: IRI mode: mode];
}

- (instancetype)init
{
	OF_INVALID_INIT_METHOD
}

- (instancetype)initWithScheme: (OFString *)scheme
{
	self = [super init];

	@try {
		_scheme = [scheme copy];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_scheme release];

	[super dealloc];
}

- (OFStream *)openItemAtIRI: (OFIRI *)IRI mode: (OFString *)mode
{
	OF_UNRECOGNIZED_SELECTOR
}

- (OFFileAttributes)attributesOfItemAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)setAttributes: (OFFileAttributes)attributes ofItemAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (bool)fileExistsAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (bool)directoryExistsAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)createDirectoryAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (OFArray OF_GENERIC(OFIRI *) *)contentsOfDirectoryAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)removeItemAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)linkItemAtIRI: (OFIRI *)source toIRI: (OFIRI *)destination
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)createSymbolicLinkAtIRI: (OFIRI *)destination
	    withDestinationPath: (OFString *)source
{
	OF_UNRECOGNIZED_SELECTOR
}

- (bool)copyItemAtIRI: (OFIRI *)source toIRI: (OFIRI *)destination
{
	return false;
}

- (bool)moveItemAtIRI: (OFIRI *)source toIRI: (OFIRI *)destination
{
	return false;
}

- (OFData *)extendedAttributeDataForName: (OFString *)name
			     ofItemAtIRI: (OFIRI *)IRI
{
	OFData *data;

	[self getExtendedAttributeData: &data
			       andType: NULL
			       forName: name
			   ofItemAtIRI: IRI];

	return data;
}

- (void)getExtendedAttributeData: (OFData **)data
			 andType: (id *)type
			 forName: (OFString *)name
		     ofItemAtIRI: (OFIRI *)IRI
{
	/*
	 * Only call into -[extendedAttributeDataForName:ofItemAtIRI:] if it
	 * has been overridden. This is to be backwards-compatible to
	 * subclasses that predate the introduction of
	 * -[getExtendedAttributeData:andType:forName:ofItemAtIRI:].
	 * Without this check, this would result in an infinite loop.
	 */
	SEL selector = @selector(extendedAttributeDataForName:ofItemAtIRI:);

	if (class_getMethodImplementation(object_getClass(self), selector) !=
	    class_getMethodImplementation([OFIRIHandler class], selector)) {
		/*
		 * Use -[performSelector:withObject:withObject:] to avoid
		 * deprecation warning. This entire thing is purely for
		 * backwards compatibility.
		 */
		*data = [self performSelector: selector
				   withObject: name
				   withObject: IRI];
	
		if (type != NULL)
			*type = nil;

		return;
	}

	OF_UNRECOGNIZED_SELECTOR
}

- (void)setExtendedAttributeData: (OFData *)data
			 forName: (OFString *)name
		     ofItemAtIRI: (OFIRI *)IRI
{
	[self setExtendedAttributeData: data
			       andType: nil
			       forName: name
			   ofItemAtIRI: IRI];
}

- (void)setExtendedAttributeData: (OFData *)data
			 andType: (id)type
			 forName: (OFString *)name
		     ofItemAtIRI: (OFIRI *)IRI
{

	if (type == nil) {
		/*
		 * Only call into
		 * -[setExtendedAttributeData:forName:ofItemAtIRI:] if it has
		 * been overridden. This is to be backwards-compatible to
		 * subclasses that predate the introduction of
		 * -[setExtendedAttributeData:andType:forName:ofItemAtIRI:].
		 * Without this check, this would result in an infinite loop.
		 */
		SEL selector =
		    @selector(setExtendedAttributeData:forName:ofItemAtIRI:);

		if (class_getMethodImplementation(object_getClass(self),
		    selector) !=
		    class_getMethodImplementation([OFIRIHandler class],
		    selector)) {
			/*
			 * Use
			 * -[performSelector:withObject:withObject:withObject:]
			 * to avoid deprecation warning. This entire thing is
			 * purely for backwards compatibility.
			 */
			[self performSelector: selector
				   withObject: data
				   withObject: name
				   withObject: IRI];
			return;
		}
	}

	OF_UNRECOGNIZED_SELECTOR
}

- (void)removeExtendedAttributeForName: (OFString *)name
			   ofItemAtIRI: (OFIRI *)IRI
{
	OF_UNRECOGNIZED_SELECTOR
}
@end