ObjFW  Artifact [e992bd3e10]

Artifact e992bd3e109760145485760df98186f4eecf5d2b2fe6d5362975b11d492dabee:

• File src/OFKernelEventObserver.m — part of check-in [45518ae7b7] at 2016-03-20 14:07:47 on branch trunk — Use the locked queue for kqueue and epoll as well

  _readObjects must only be changed from the thread running the observer
  and not from a thread adding or removing objects to observe. This is
  already handled by the locked queue used by poll and select, so the best
  way to solve this is to use the locked queue for kqueue and epoll as
  well. (user: js, size: 8571) [annotate] [blame] [check-ins using]

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016
 *   Jonathan Schleifer <js@heap.zone>
 *
 * All rights reserved.
 *
 * This file is part of ObjFW. It may be distributed under the terms of the
 * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
 * the packaging of this file.
 *
 * Alternatively, it may be distributed under the terms of the GNU General
 * Public License, either version 2 or 3, which can be found in the file
 * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
 * file.
 */

#define __NO_EXT_QNX

#include "config.h"

#import "OFKernelEventObserver.h"
#import "OFKernelEventObserver+Private.h"
#import "OFArray.h"
#import "OFDataArray.h"
#import "OFStream.h"
#import "OFStream+Private.h"
#ifndef OF_HAVE_PIPE
# import "OFStreamSocket.h"
#endif
#import "OFDate.h"
#ifdef OF_HAVE_THREADS
# import "OFMutex.h"
#endif

#ifdef HAVE_KQUEUE
# import "OFKernelEventObserver_kqueue.h"
#endif
#ifdef HAVE_EPOLL
# import "OFKernelEventObserver_epoll.h"
#endif
#if defined(HAVE_POLL_H) || defined(OF_WII)
# import "OFKernelEventObserver_poll.h"
#endif
#if defined(HAVE_SYS_SELECT_H) || defined(OF_WINDOWS)
# import "OFKernelEventObserver_select.h"
#endif

#import "OFInitializationFailedException.h"
#import "OFInvalidArgumentException.h"
#import "OFOutOfRangeException.h"

#import "socket.h"
#import "socket_helpers.h"

enum {
	QUEUE_ADD = 0,
	QUEUE_REMOVE = 1,
	QUEUE_READ = 0,
	QUEUE_WRITE = 2
};
#define QUEUE_ACTION (QUEUE_ADD | QUEUE_REMOVE)

@implementation OFKernelEventObserver
@synthesize delegate = _delegate;

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

	if (!of_socket_init())
		@throw [OFInitializationFailedException
		    exceptionWithClass: self];
}

+ (instancetype)observer
{
	return [[[self alloc] init] autorelease];
}

+ alloc
{
	if (self == [OFKernelEventObserver class])
#if defined(HAVE_KQUEUE)
		return [OFKernelEventObserver_kqueue alloc];
#elif defined(HAVE_EPOLL)
		return [OFKernelEventObserver_epoll alloc];
#elif defined(HAVE_POLL_H) || defined(OF_WII)
		return [OFKernelEventObserver_poll alloc];
#elif defined(HAVE_SYS_SELECT_H) || defined(OF_WINDOWS)
		return [OFKernelEventObserver_select alloc];
#else
# error No kqueue / epoll / poll / select found!
#endif

	return [super alloc];
}

- init
{
	self = [super init];

	@try {
#if !defined(OF_HAVE_PIPE) && !defined(OF_WII)
		socklen_t cancelAddrLen;
#endif

		_readObjects = [[OFMutableArray alloc] init];
		_writeObjects = [[OFMutableArray alloc] init];

#ifdef OF_HAVE_PIPE
		if (pipe(_cancelFD))
			@throw [OFInitializationFailedException
			    exceptionWithClass: [self class]];
#else
		_cancelFD[0] = _cancelFD[1] = socket(AF_INET, SOCK_DGRAM, 0);

		if (_cancelFD[0] == INVALID_SOCKET)
			@throw [OFInitializationFailedException
			    exceptionWithClass: [self class]];

		_cancelAddr.sin_family = AF_INET;
		_cancelAddr.sin_port = 0;
		_cancelAddr.sin_addr.s_addr = inet_addr("127.0.0.1");

# ifdef OF_WII
		_cancelAddr.sin_len = 8;
		/* The Wii does not accept port 0 as "choose any free port" */
		_cancelAddr.sin_port = of_socket_port_find(SOCK_DGRAM);
# endif

		if (bind(_cancelFD[0], (struct sockaddr*)&_cancelAddr,
		    sizeof(_cancelAddr)))
			@throw [OFInitializationFailedException
			    exceptionWithClass: [self class]];

# ifndef OF_WII
		cancelAddrLen = sizeof(_cancelAddr);
		if (of_getsockname(_cancelFD[0], (struct sockaddr*)&_cancelAddr,
		    &cancelAddrLen) != 0)
			@throw [OFInitializationFailedException
			    exceptionWithClass: [self class]];
# endif
#endif

#ifdef OF_HAVE_THREADS
		_mutex = [[OFMutex alloc] init];
#endif

		_queueActions = [[OFDataArray alloc]
		    initWithItemSize: sizeof(int)];
		_queueObjects = [[OFMutableArray alloc] init];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	close(_cancelFD[0]);
	if (_cancelFD[1] != _cancelFD[0])
		close(_cancelFD[1]);

#ifdef OF_WII
	of_socket_port_free(_cancelAddr.sin_port, SOCK_DGRAM);
#endif

	[_readObjects release];
	[_writeObjects release];

#ifdef OF_HAVE_THREADS
	[_mutex release];
#endif

	[_queueActions release];
	[_queueObjects release];

	[super dealloc];
}

- (void)addObjectForReading: (id <OFReadyForReadingObserving>)object
{
#ifdef OF_HAVE_THREADS
	[_mutex lock];
	@try {
#endif
		int action = QUEUE_ADD | QUEUE_READ;

		[_queueActions addItem: &action];
		[_queueObjects addObject: object];
#ifdef OF_HAVE_THREADS
	} @finally {
		[_mutex unlock];
	}
#endif

	[self cancel];
}

- (void)addObjectForWriting: (id <OFReadyForWritingObserving>)object
{
#ifdef OF_HAVE_THREADS
	[_mutex lock];
	@try {
#endif
		int action = QUEUE_ADD | QUEUE_WRITE;

		[_queueActions addItem: &action];
		[_queueObjects addObject: object];
#ifdef OF_HAVE_THREADS
	} @finally {
		[_mutex unlock];
	}
#endif

	[self cancel];
}

- (void)removeObjectForReading: (id <OFReadyForReadingObserving>)object
{
#ifdef OF_HAVE_THREADS
	[_mutex lock];
	@try {
#endif
		int action = QUEUE_REMOVE | QUEUE_READ;

		[_queueActions addItem: &action];
		[_queueObjects addObject: object];
#ifdef OF_HAVE_THREADS
	} @finally {
		[_mutex unlock];
	}
#endif

	[self cancel];
}

- (void)removeObjectForWriting: (id <OFReadyForWritingObserving>)object
{
#ifdef OF_HAVE_THREADS
	[_mutex lock];
	@try {
#endif
		int action = QUEUE_REMOVE | QUEUE_WRITE;

		[_queueActions addItem: &action];
		[_queueObjects addObject: object];
#ifdef OF_HAVE_THREADS
	} @finally {
		[_mutex unlock];
	}
#endif

	[self cancel];
}

- (void)OF_addObjectForReading: (id <OFReadyForReadingObserving>)object
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)OF_addObjectForWriting: (id <OFReadyForWritingObserving>)object
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)OF_removeObjectForReading: (id <OFReadyForReadingObserving>)object
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)OF_removeObjectForWriting: (id <OFReadyForWritingObserving>)object
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)OF_processQueue
{
	void *pool = objc_autoreleasePoolPush();

#ifdef OF_HAVE_THREADS
	[_mutex lock];
	@try {
#endif
		int *queueActions = [_queueActions items];
		id const *queueObjects = [_queueObjects objects];
		size_t count = [_queueActions count];

		OF_ENSURE([_queueObjects count] == count);

		for (size_t i = 0; i < count; i++) {
			int action = queueActions[i];
			id object = queueObjects[i];

			switch (action) {
			case QUEUE_ADD | QUEUE_READ:
				[_readObjects addObject: object];

				@try {
					[self OF_addObjectForReading: object];
				} @catch (id e) {
					[_readObjects
					    removeObjectIdenticalTo: object];

					@throw e;
				}

				break;
			case QUEUE_ADD | QUEUE_WRITE:
				[_writeObjects addObject: object];

				@try {
					[self OF_addObjectForWriting: object];
				} @catch (id e) {
					[_writeObjects
					    removeObjectIdenticalTo: object];

					@throw e;
				}

				break;
			case QUEUE_REMOVE | QUEUE_READ:
				[self OF_removeObjectForReading: object];

				[_readObjects removeObjectIdenticalTo: object];

				break;
			case QUEUE_REMOVE | QUEUE_WRITE:
				[self OF_removeObjectForWriting: object];

				[_writeObjects removeObjectIdenticalTo: object];

				break;
			default:
				OF_ENSURE(0);
			}
		}

		[_queueActions removeAllItems];
		[_queueObjects removeAllObjects];
#ifdef OF_HAVE_THREADS
	} @finally {
		[_mutex unlock];
	}
#endif

	objc_autoreleasePoolPop(pool);
}

- (bool)OF_processReadBuffers
{
	bool foundInReadBuffer = false;

	for (id object in _readObjects) {
		void *pool = objc_autoreleasePoolPush();

		if ([object isKindOfClass: [OFStream class]] &&
		    [object hasDataInReadBuffer] &&
		    ![object OF_isWaitingForDelimiter]) {
			if ([_delegate respondsToSelector:
			    @selector(objectIsReadyForReading:)])
				[_delegate objectIsReadyForReading: object];

			foundInReadBuffer = true;
		}

		objc_autoreleasePoolPop(pool);
	}

	/*
	 * As long as we have data in the read buffer for any stream, we don't
	 * want to block.
	 */
	return foundInReadBuffer;
}

- (void)observe
{
	[self observeForTimeInterval: -1];
}

- (void)observeForTimeInterval: (of_time_interval_t)timeInterval
{
	OF_UNRECOGNIZED_SELECTOR
}

- (void)observeUntilDate: (OFDate*)date
{
	[self observeForTimeInterval: [date timeIntervalSinceNow]];
}

- (void)cancel
{
#ifdef OF_HAVE_PIPE
	OF_ENSURE(write(_cancelFD[1], "", 1) > 0);
#else
# ifndef OF_WII
	OF_ENSURE(sendto(_cancelFD[1], "", 1, 0,
	    (struct sockaddr*)&_cancelAddr, sizeof(_cancelAddr)) > 0);
# else
	OF_ENSURE(sendto(_cancelFD[1], "", 1, 0,
	    (struct sockaddr*)&_cancelAddr, 8) > 0);
# endif
#endif
}
@end