ObjFW  Artifact [5a3f2982c0]

Artifact 5a3f2982c02feaef3512c78ec95bec4add17aa72c9addf2452b530fc4f337451:

• File src/OFThread.m — part of check-in [e7f4f80e23] at 2020-01-24 03:03:32 on branch trunk — runtime: Correctly handle AR pool push during pop

  Getting a pointer and increasing it until we reach the top pointer does
  not work: Releasing an object can temporarily create new autorelease
  pools, which can trigger resizing of "objects" using realloc, which can
  move it to a different address, which will then lead to continuing to
  iterate on a now invalid pointer.

  This is now solved by using an index into "objects" instead. Since we're
  now indexing for the pop, let's use indexes everywhere, as they're more
  readable anyway.

  While debugging this, I noticed that the last pool is popped quite
  frequently, only for a new pool to be pushed immediately again. This
  resulted in a free followed by a malloc every time. Instead, keep the
  pool, but let OFThread explicitly say when to free everything. (user: js, size: 10770) [annotate] [blame] [check-ins using] [more...]

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017,
 *               2018, 2019, 2020
 *   Jonathan Schleifer <js@nil.im>
 *
 * 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.
 */

#include "config.h"

#define _POSIX_TIMERS
#define __NO_EXT_QNX

#include <errno.h>

#include <stdlib.h>
#include <math.h>
#include <time.h>

#ifdef OF_HAVE_SCHED_YIELD
# include <sched.h>
#endif
#include "unistd_wrapper.h"

#include "platform.h"

#ifdef OF_AMIGAOS
# include <proto/exec.h>
# include <proto/dos.h>
#endif

#ifdef OF_WII
# define nanosleep ogc_nanosleep
# include <ogcsys.h>
# undef nanosleep
#endif

#ifdef OF_NINTENDO_3DS
# include <3ds/svc.h>
#endif

#import "OFThread.h"
#import "OFThread+Private.h"
#import "OFDate.h"
#import "OFDictionary.h"
#ifdef OF_HAVE_SOCKETS
# import "OFDNSResolver.h"
#endif
#import "OFLocale.h"
#import "OFRunLoop.h"
#import "OFString.h"

#ifdef OF_WINDOWS
# include <windows.h>
#endif

#ifdef OF_NINTENDO_DS
# define asm __asm__
# include <nds.h>
# undef asm
#endif

#import "OFInitializationFailedException.h"
#import "OFInvalidArgumentException.h"
#import "OFNotImplementedException.h"
#import "OFOutOfRangeException.h"
#ifdef OF_HAVE_THREADS
# import "OFThreadJoinFailedException.h"
# import "OFThreadStartFailedException.h"
# import "OFThreadStillRunningException.h"
#endif

#ifdef OF_HAVE_ATOMIC_OPS
# import "atomic.h"
#endif

#if defined(OF_HAVE_THREADS)
# import "tlskey.h"
# if defined(OF_AMIGAOS) && defined(OF_HAVE_SOCKETS)
#  import "socket.h"
# endif

static of_tlskey_t threadSelfKey;
static OFThread *mainThread;
#elif defined(OF_HAVE_SOCKETS)
static OFDNSResolver *DNSResolver;
#endif

@implementation OFThread
#ifdef OF_HAVE_THREADS
static void
callMain(id object)
{
	OFThread *thread = (OFThread *)object;
	OFString *name;

	if (!of_tlskey_set(threadSelfKey, thread))
		@throw [OFInitializationFailedException
		    exceptionWithClass: thread.class];

#ifndef OF_OBJFW_RUNTIME
	thread->_pool = objc_autoreleasePoolPush();
#endif

	name = thread.name;
	if (name != nil)
		of_thread_set_name(
		    [name cStringWithEncoding: [OFLocale encoding]]);
	else
		of_thread_set_name(object_getClassName(thread));

#if defined(OF_AMIGAOS) && defined(OF_HAVE_SOCKETS)
	if (thread.supportsSockets)
		if (!of_socket_init())
			@throw [OFInitializationFailedException
			    exceptionWithClass: thread.class];
#endif

	/*
	 * Nasty workaround for thread implementations which can't return a
	 * pointer on join, or don't have a way to exit a thread.
	 */
	if (setjmp(thread->_exitEnv) == 0) {
# ifdef OF_HAVE_BLOCKS
		if (thread->_threadBlock != NULL)
			thread->_returnValue = [thread->_threadBlock() retain];
		else
# endif
			thread->_returnValue = [[thread main] retain];
	}

	[thread handleTermination];

#ifdef OF_OBJFW_RUNTIME
	objc_autoreleasePoolPop((void *)(uintptr_t)-1);
#else
	objc_autoreleasePoolPop(thread->_pool);
#endif

#if defined(OF_AMIGAOS) && defined(OF_HAVE_SOCKETS)
	if (thread.supportsSockets)
		of_socket_deinit();
#endif

	thread->_running = OF_THREAD_WAITING_FOR_JOIN;

	[thread release];
}

@synthesize name = _name;
# ifdef OF_HAVE_BLOCKS
@synthesize threadBlock = _threadBlock;
# endif

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

	if (!of_tlskey_new(&threadSelfKey))
		@throw [OFInitializationFailedException
		    exceptionWithClass: self];
}

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

# ifdef OF_HAVE_BLOCKS
+ (instancetype)threadWithThreadBlock: (of_thread_block_t)threadBlock
{
	return [[[self alloc] initWithThreadBlock: threadBlock] autorelease];
}
# endif

+ (OFThread *)currentThread
{
	return of_tlskey_get(threadSelfKey);
}

+ (OFThread *)mainThread
{
	return mainThread;
}

+ (bool)isMainThread
{
	if (mainThread == nil)
		return false;

	return (of_tlskey_get(threadSelfKey) == mainThread);
}

+ (OFMutableDictionary *)threadDictionary
{
	OFThread *thread = of_tlskey_get(threadSelfKey);

	if (thread == nil)
		return nil;

	if (thread->_threadDictionary == nil)
		thread->_threadDictionary = [[OFMutableDictionary alloc] init];

	return thread->_threadDictionary;
}
#endif

#ifdef OF_HAVE_SOCKETS
+ (OFDNSResolver *)DNSResolver
{
# ifdef OF_HAVE_THREADS
	OFThread *thread = of_tlskey_get(threadSelfKey);

	if (thread == nil)
		return nil;

	if (thread->_DNSResolver == nil)
		thread->_DNSResolver = [[OFDNSResolver alloc] init];

	return thread->_DNSResolver;
# else
	if (DNSResolver == nil)
		DNSResolver = [[OFDNSResolver alloc] init];

	return DNSResolver;
# endif
}
#endif

+ (void)sleepForTimeInterval: (of_time_interval_t)timeInterval
{
	if (timeInterval < 0)
		return;

#if defined(OF_WINDOWS)
	if (timeInterval * 1000 > UINT_MAX)
		@throw [OFOutOfRangeException exception];

	Sleep((unsigned int)(timeInterval * 1000));
#elif defined(OF_NINTENDO_3DS)
	if (timeInterval * 1000000000 > INT64_MAX)
		@throw [OFOutOfRangeException exception];

	svcSleepThread((int64_t)(timeInterval * 1000000000));
#elif defined(HAVE_NANOSLEEP)
	struct timespec rqtp;

	rqtp.tv_sec = (time_t)timeInterval;
	rqtp.tv_nsec = (timeInterval - rqtp.tv_sec) * 1000000000;

	if (rqtp.tv_sec != trunc(timeInterval))
		@throw [OFOutOfRangeException exception];

	nanosleep(&rqtp, NULL);
#elif defined(OF_AMIGAOS)
	if (timeInterval * 50 > ULONG_MAX)
		@throw [OFOutOfRangeException exception];

	Delay(timeInterval * 50);
#elif defined(OF_NINTENDO_DS)
	uint64_t counter;

	if (timeInterval > UINT64_MAX / 60)
		@throw [OFOutOfRangeException exception];

	counter = timeInterval * 60;
	while (counter--)
		swiWaitForVBlank();
#else
	if (timeInterval > UINT_MAX)
		@throw [OFOutOfRangeException exception];

	sleep((unsigned int)timeInterval);
	usleep((unsigned int)
	    (timeInterval - (unsigned int)timeInterval) * 1000000);
#endif
}

+ (void)sleepUntilDate: (OFDate *)date
{
	[self sleepForTimeInterval: date.timeIntervalSinceNow];
}

+ (void)yield
{
#ifdef OF_HAVE_SCHED_YIELD
	sched_yield();
#else
	[self sleepForTimeInterval: 0];
#endif
}

#ifdef OF_HAVE_THREADS
+ (void)terminate
{
	[self terminateWithObject: nil];

	/*
	 * For some reason, Clang thinks terminateWithObject: can return - even
	 * though it is declared OF_NO_RETURN - and warns that terminate
	 * returns while being declared OF_NO_RETURN.
	 */
	OF_UNREACHABLE
}

+ (void)terminateWithObject: (id)object
{
	OFThread *thread = of_tlskey_get(threadSelfKey);

	if (thread == mainThread)
		@throw [OFInvalidArgumentException exception];

	OF_ENSURE(thread != nil);

	thread->_returnValue = [object retain];
	longjmp(thread->_exitEnv, 1);

	OF_UNREACHABLE
}

+ (void)setName: (OFString *)name
{
	[OFThread currentThread].name = name;

	if (name != nil)
		of_thread_set_name(
		    [name cStringWithEncoding: [OFLocale encoding]]);
	else
		of_thread_set_name(class_getName(self.class));
}

+ (OFString *)name
{
	return [OFThread currentThread].name;
}

+ (void)of_createMainThread
{
	mainThread = [[OFThread alloc] init];
	mainThread->_thread = of_thread_current();
	mainThread->_running = OF_THREAD_RUNNING;

	if (!of_tlskey_set(threadSelfKey, mainThread))
		@throw [OFInitializationFailedException
		    exceptionWithClass: self];
}

- (instancetype)init
{
	self = [super init];

	@try {
		if (!of_thread_attr_init(&_attr))
			@throw [OFInitializationFailedException
			    exceptionWithClass: self.class];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

# ifdef OF_HAVE_BLOCKS
- (instancetype)initWithThreadBlock: (of_thread_block_t)threadBlock
{
	self = [self init];

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

	return self;
}
# endif

- (id)main
{
	[[OFRunLoop currentRunLoop] run];

	return nil;
}

- (void)handleTermination
{
	OFRunLoop *oldRunLoop = _runLoop;
	_runLoop = nil;
	[oldRunLoop release];

	[_threadDictionary release];
	_threadDictionary = nil;

# ifdef OF_HAVE_SOCKETS
	[_DNSResolver release];
	_DNSResolver = nil;
# endif
}

- (void)start
{
	if (_running == OF_THREAD_RUNNING)
		@throw [OFThreadStillRunningException
		    exceptionWithThread: self];

	if (_running == OF_THREAD_WAITING_FOR_JOIN) {
		of_thread_detach(_thread);
		[_returnValue release];
	}

	[self retain];

	_running = OF_THREAD_RUNNING;

	if (!of_thread_new(&_thread,
	    [_name cStringWithEncoding: [OFLocale encoding]], callMain, self,
	    &_attr)) {
		[self release];
		@throw [OFThreadStartFailedException
		    exceptionWithThread: self
				  errNo: errno];
	}
}

- (id)join
{
	if (_running == OF_THREAD_NOT_RUNNING)
		@throw [OFThreadJoinFailedException
		    exceptionWithThread: self
				  errNo: EINVAL];

	if (!of_thread_join(_thread))
		@throw [OFThreadJoinFailedException exceptionWithThread: self
								  errNo: errno];

	_running = OF_THREAD_NOT_RUNNING;

	return _returnValue;
}

- (id)copy
{
	return [self retain];
}

- (OFRunLoop *)runLoop
{
# if defined(OF_HAVE_ATOMIC_OPS) && !defined(__clang_analyzer__)
	if (_runLoop == nil) {
		OFRunLoop *tmp = [[OFRunLoop alloc] init];

		if (!of_atomic_ptr_cmpswap((void **)&_runLoop, nil, tmp))
			[tmp release];
	}
# else
	@synchronized (self) {
		if (_runLoop == nil)
			_runLoop = [[OFRunLoop alloc] init];
	}
# endif

	return _runLoop;
}

- (float)priority
{
	return _attr.priority;
}

- (void)setPriority: (float)priority
{
	if (_running == OF_THREAD_RUNNING)
		@throw [OFThreadStillRunningException
		    exceptionWithThread: self];

	_attr.priority = priority;
}

- (size_t)stackSize
{
	return _attr.stackSize;
}

- (void)setStackSize: (size_t)stackSize
{
	if (_running == OF_THREAD_RUNNING)
		@throw [OFThreadStillRunningException
		    exceptionWithThread: self];

	_attr.stackSize = stackSize;
}

- (bool)supportsSockets
{
	return _supportsSockets;
}

- (void)setSupportsSockets: (bool)supportsSockets
{
	if (_running == OF_THREAD_RUNNING)
		@throw [OFThreadStillRunningException
		    exceptionWithThread: self];

	_supportsSockets = supportsSockets;
}

- (void)dealloc
{
	if (_running == OF_THREAD_RUNNING)
		@throw [OFThreadStillRunningException
		    exceptionWithThread: self];

	/*
	 * We should not be running anymore, but call detach in order to free
	 * the resources.
	 */
	if (_running == OF_THREAD_WAITING_FOR_JOIN)
		of_thread_detach(_thread);

	[_returnValue release];
# ifdef OF_HAVE_BLOCKS
	[_threadBlock release];
# endif

	[super dealloc];
}
#else
- (instancetype)init
{
	OF_INVALID_INIT_METHOD
}
#endif
@end