ObjFW  Check-in [ae4879fe0d]

 *	  and objects should be retained, released, compared and hashed.
 */
OF_SUBCLASSING_RESTRICTED
@interface OFMapTable: OFObject <OFCopying, OFFastEnumeration>
{
	OFMapTableFunctions _keyFunctions, _objectFunctions;
	struct OFMapTableBucket *_Nonnull *_Nullable _buckets;
	unsigned long _count, _capacity;
	unsigned char _rotate;
	unsigned long _mutations;
}

/**
 * @brief The key functions used by the map table.
 */

 * @brief A class which provides methods to enumerate through an OFMapTable's
 *	  keys or objects.
 */
@interface OFMapTableEnumerator: OFObject
{
	OFMapTable *_mapTable;
	struct OFMapTableBucket *_Nonnull *_Nullable _buckets;
	unsigned long _capacity, _mutations, *_Nullable _mutationsPtr;
	unsigned long _position;
}

- (instancetype)init OF_UNAVAILABLE;

/**
 * @brief Returns a pointer to the next object, or NULL if the enumeration
 *	  finished.

#import "OFMapTable+Private.h"
#import "OFEnumerator.h"

#import "OFEnumerationMutationException.h"
#import "OFInvalidArgumentException.h"
#import "OFOutOfRangeException.h"

extern unsigned long OFHashSeed;

static const unsigned long minCapacity = 16;

struct OFMapTableBucket {
	void *key, *object;
	unsigned long hash;
};
static struct OFMapTableBucket deletedBucket = { 0 };

static void *
defaultRetain(void *object)
{
	return object;

	return (object1 == object2);
}

OF_DIRECT_MEMBERS
@interface OFMapTableEnumerator ()
- (instancetype)of_initWithMapTable: (OFMapTable *)mapTable
			    buckets: (struct OFMapTableBucket **)buckets
			   capacity: (unsigned long)capacity
		   mutationsPointer: (unsigned long *)mutationsPtr
    OF_METHOD_FAMILY(init);
@end

@interface OFMapTableKeyEnumerator: OFMapTableEnumerator
@end

		SET_DEFAULT(_objectFunctions.retain, defaultRetain);
		SET_DEFAULT(_objectFunctions.release, defaultRelease);
		SET_DEFAULT(_objectFunctions.hash, defaultHash);
		SET_DEFAULT(_objectFunctions.equal, defaultEqual);

#undef SET_DEFAULT

		if (capacity > ULONG_MAX / sizeof(*_buckets) ||
		    capacity > ULONG_MAX / 8)
			@throw [OFOutOfRangeException exception];

		for (_capacity = 1; _capacity < capacity;) {
			if (_capacity > ULONG_MAX / 2)
				@throw [OFOutOfRangeException exception];

			_capacity *= 2;
		}

		if (capacity * 8 / _capacity >= 6)
			if (_capacity <= ULONG_MAX / 2)
				_capacity *= 2;

		if (_capacity < minCapacity)
			_capacity = minCapacity;

		_buckets = OFAllocZeroedMemory(_capacity, sizeof(*_buckets));

		if (OFHashSeed != 0)
			_rotate = OFRandom16() & 31;
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	for (unsigned long i = 0; i < _capacity; i++) {
		if (_buckets[i] != NULL && _buckets[i] != &deletedBucket) {
			_keyFunctions.release(_buckets[i]->key);
			_objectFunctions.release(_buckets[i]->object);

			OFFreeMemory(_buckets[i]);
		}
	}

	OFFreeMemory(_buckets);

	[super dealloc];
}

static void
resizeForCount(OFMapTable *self, unsigned long count)
{
	unsigned long fullness, capacity;
	struct OFMapTableBucket **buckets;

	if (count > ULONG_MAX / sizeof(*self->_buckets) ||
	    count > ULONG_MAX / 8)
		@throw [OFOutOfRangeException exception];

	fullness = count * 8 / self->_capacity;

	if (fullness >= 6) {
		if (self->_capacity > ULONG_MAX / 2)
			return;

		capacity = self->_capacity * 2;
	} else if (fullness <= 1)
		capacity = self->_capacity / 2;
	else
		return;

	/*
	 * Don't downsize if we have an initial capacity or if we would fall
	 * below the minimum capacity.
	 */
	if ((capacity < self->_capacity && count > self->_count) ||
	    capacity < minCapacity)
		return;

	buckets = OFAllocZeroedMemory(capacity, sizeof(*buckets));

	for (unsigned long i = 0; i < self->_capacity; i++) {
		if (self->_buckets[i] != NULL &&
		    self->_buckets[i] != &deletedBucket) {
			unsigned long j, last;

			last = capacity;

			for (j = self->_buckets[i]->hash & (capacity - 1);
			    j < last && buckets[j] != NULL; j++);

			/* In case the last bucket is already used */

	OFFreeMemory(self->_buckets);
	self->_buckets = buckets;
	self->_capacity = capacity;
}

static void
setObject(OFMapTable *restrict self, void *key, void *object,
    unsigned long hash)
{
	unsigned long i, last;
	void *old;

	if (key == NULL || object == NULL)
		@throw [OFInvalidArgumentException exception];

	hash = OFRotateLeft(hash, self->_rotate);
	last = self->_capacity;

	mapTable = object;

	if (mapTable->_count != _count ||
	    mapTable->_keyFunctions.equal != _keyFunctions.equal ||
	    mapTable->_objectFunctions.equal != _objectFunctions.equal)
		return false;

	for (unsigned long i = 0; i < _capacity; i++) {
		if (_buckets[i] != NULL && _buckets[i] != &deletedBucket) {
			void *objectIter =
			    [mapTable objectForKey: _buckets[i]->key];

			if (!_objectFunctions.equal(objectIter,
			    _buckets[i]->object))
				return false;

{
	OFMapTable *copy = [[OFMapTable alloc]
	    initWithKeyFunctions: _keyFunctions
		 objectFunctions: _objectFunctions
			capacity: _capacity];

	@try {
		for (unsigned long i = 0; i < _capacity; i++)
			if (_buckets[i] != NULL &&
			    _buckets[i] != &deletedBucket)
				setObject(copy, _buckets[i]->key,
				    _buckets[i]->object,
				    OFRotateRight(_buckets[i]->hash, _rotate));
	} @catch (id e) {
		[copy release];
		@throw e;
	}

	return copy;
}

- (size_t)count
{
	return _count;
}

- (void *)objectForKey: (void *)key
{
	unsigned long i, hash, last;

	if (key == NULL)
		@throw [OFInvalidArgumentException exception];

	hash = OFRotateLeft(_keyFunctions.hash(key), _rotate);
	last = _capacity;

	for (i = hash & (_capacity - 1); i < last && _buckets[i] != NULL; i++) {
		if (_buckets[i] == &deletedBucket)
			continue;

		if (_keyFunctions.equal(_buckets[i]->key, key))

	}

	return NULL;
}

- (void)setObject: (void *)object forKey: (void *)key
{
	setObject(self, key, object,_keyFunctions.hash(key));
}

- (void)removeObjectForKey: (void *)key
{
	unsigned long i, hash, last;

	if (key == NULL)
		@throw [OFInvalidArgumentException exception];

	hash = OFRotateLeft(_keyFunctions.hash(key), _rotate);
	last = _capacity;

	for (i = hash & (_capacity - 1); i < last && _buckets[i] != NULL; i++) {
		if (_buckets[i] == &deletedBucket)
			continue;

		if (_keyFunctions.equal(_buckets[i]->key, key)) {

			return;
		}
	}
}

- (void)removeAllObjects
{
	for (unsigned long i = 0; i < _capacity; i++) {
		if (_buckets[i] != NULL) {
			if (_buckets[i] == &deletedBucket) {
				_buckets[i] = NULL;
				continue;
			}

			_keyFunctions.release(_buckets[i]->key);

}

- (bool)containsObject: (void *)object
{
	if (object == NULL || _count == 0)
		return false;

	for (unsigned long i = 0; i < _capacity; i++)
		if (_buckets[i] != NULL && _buckets[i] != &deletedBucket)
			if (_objectFunctions.equal(_buckets[i]->object, object))
				return true;

	return false;
}

- (bool)containsObjectIdenticalTo: (void *)object
{
	if (object == NULL || _count == 0)
		return false;

	for (unsigned long i = 0; i < _capacity; i++)
		if (_buckets[i] != NULL && _buckets[i] != &deletedBucket)
			if (_buckets[i]->object == object)
				return true;

	return false;
}

- (instancetype)init
{
	OF_INVALID_INIT_METHOD
}

- (instancetype)of_initWithMapTable: (OFMapTable *)mapTable
			    buckets: (struct OFMapTableBucket **)buckets
			   capacity: (unsigned long)capacity
		   mutationsPointer: (unsigned long *)mutationsPtr
{
	self = [super init];

	_mapTable = [mapTable retain];
	_buckets = buckets;
	_capacity = capacity;