ObjFW  Diff

#include "config.h"

#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#import "OFBlock.h"
#ifdef OF_HAVE_ATOMIC_OPS
# import "OFAtomic.h"
#endif
#ifdef OF_HAVE_THREADS
# import "OFPlainMutex.h"
#endif

#import "OFAllocFailedException.h"
#import "OFInitializationFailedException.h"

#if defined(OF_OBJFW_RUNTIME)
# import "runtime/private.h"
#endif

#ifdef OF_HAVE_ATOMIC_OPS
# import "atomic.h"
#endif
#ifdef OF_HAVE_THREADS
# import "mutex.h"
#endif
struct Block {
	Class isa;
	int flags;
	int reserved;
	void (*invoke)(void *block, ...);
	struct {
		unsigned long reserved;
		unsigned long size;
		void (*_Nullable copyHelper)(void *dest, void *src);
		void (*_Nullable disposeHelper)(void *src);
		const char *signature;
	} *descriptor;
};

typedef struct of_block_byref_t of_block_byref_t;
struct of_block_byref_t {
struct Byref {
	Class isa;
	of_block_byref_t *forwarding;
	struct Byref *forwarding;
	int flags;
	int size;
	void (*byref_keep)(void *dest, void *src);
	void (*byref_dispose)(void *);
	void (*keepByref)(void *dest, void *src);
	void (*disposeByref)(void *);
};

enum {
	OF_BLOCK_HAS_COPY_DISPOSE = (1 << 25),
	OF_BLOCK_HAS_CTOR	  = (1 << 26),
	OF_BLOCK_IS_GLOBAL	  = (1 << 28),
	OF_BLOCK_HAS_STRET	  = (1 << 29),
	OF_BLOCK_HAS_SIGNATURE	  = (1 << 30)
	OFBlockHasCopyDispose = (1 << 25),
	OFBlockHasCtor	      = (1 << 26),
	OFBlockIsGlobal	      = (1 << 28),
	OFBlockHasStret	      = (1 << 29),
	OFBlockHasSignature   = (1 << 30)
};
#define OF_BLOCK_REFCOUNT_MASK 0xFFFF
#define OFBlockRefCountMask 0xFFFF

enum {
	OF_BLOCK_FIELD_IS_OBJECT =   3,
	OF_BLOCK_FIELD_IS_BLOCK	 =   7,
	OF_BLOCK_FIELD_IS_BYREF	 =   8,
	OF_BLOCK_FIELD_IS_WEAK	 =  16,
	OF_BLOCK_BYREF_CALLER	 = 128
	OFBlockFieldIsObject =   3,
	OFBlockFieldIsBlock  =   7,
	OFBlockFieldIsByref  =   8,
	OFBlockFieldIsWeak   =  16,
	OFBlockByrefCaller   = 128
};

@protocol RetainRelease
- (instancetype)retain;
- (void)release;
@end

#ifdef OF_OBJFW_RUNTIME
/* Begin of ObjC module */
static struct objc_class _NSConcreteStackBlock_metaclass = {
	Nil, Nil, "OFStackBlock", 8, OBJC_CLASS_INFO_METACLASS,
	sizeof(_NSConcreteStackBlock_metaclass), NULL, NULL
};

struct objc_class _NSConcreteStackBlock = {
	&_NSConcreteStackBlock_metaclass, (Class)(void *)"OFBlock",
	"OFStackBlock", 8, OBJC_CLASS_INFO_CLASS, sizeof(of_block_literal_t),
	"OFStackBlock", 8, OBJC_CLASS_INFO_CLASS, sizeof(struct Block),
	NULL, NULL
};

static struct objc_class _NSConcreteGlobalBlock_metaclass = {
	Nil, Nil, "OFGlobalBlock", 8, OBJC_CLASS_INFO_METACLASS,
	sizeof(_NSConcreteGlobalBlock_metaclass), NULL, NULL
};

struct objc_class _NSConcreteGlobalBlock = {
	&_NSConcreteGlobalBlock_metaclass, (Class)(void *)"OFBlock",
	"OFGlobalBlock", 8, OBJC_CLASS_INFO_CLASS, sizeof(of_block_literal_t),
	"OFGlobalBlock", 8, OBJC_CLASS_INFO_CLASS, sizeof(struct Block),
	NULL, NULL
};

static struct objc_class _NSConcreteMallocBlock_metaclass = {
	Nil, Nil, "OFMallocBlock", 8, OBJC_CLASS_INFO_METACLASS,
	sizeof(_NSConcreteMallocBlock_metaclass), NULL, NULL
};

struct objc_class _NSConcreteMallocBlock = {
	&_NSConcreteMallocBlock_metaclass, (Class)(void *)"OFBlock",
	"OFMallocBlock", 8, OBJC_CLASS_INFO_CLASS, sizeof(of_block_literal_t),
	"OFMallocBlock", 8, OBJC_CLASS_INFO_CLASS, sizeof(struct Block),
	NULL, NULL
};

static struct {
	unsigned long unknown;
	struct objc_selector *selectorRefs;
	uint16_t classDefsCount, categoryDefsCount;

#endif

static struct {
	Class isa;
} alloc_failed_exception;

#ifndef OF_HAVE_ATOMIC_OPS
# define NUM_SPINLOCKS 8	/* needs to be a power of 2 */
# define SPINLOCK_HASH(p) ((uintptr_t)p >> 4) & (NUM_SPINLOCKS - 1)
static of_spinlock_t blockSpinlocks[NUM_SPINLOCKS];
static of_spinlock_t byrefSpinlocks[NUM_SPINLOCKS];
# define numSpinlocks 8	/* needs to be a power of 2 */
# define SPINLOCK_HASH(p) ((uintptr_t)p >> 4) & (numSpinlocks - 1)
static OFSpinlock blockSpinlocks[numSpinlocks];
static OFSpinlock byrefSpinlocks[numSpinlocks];
#endif

void *
_Block_copy(const void *block_)
{
	of_block_literal_t *block = (of_block_literal_t *)block_;
	struct Block *block = (struct Block *)block_;

	if ([(id)block isMemberOfClass: (Class)&_NSConcreteStackBlock]) {
		of_block_literal_t *copy;
		struct Block *copy;

		if ((copy = malloc(block->descriptor->size)) == NULL) {
			alloc_failed_exception.isa =
			    [OFAllocFailedException class];
			@throw (OFAllocFailedException *)
			    &alloc_failed_exception;
		}
		memcpy(copy, block, block->descriptor->size);

		object_setClass((id)copy, (Class)&_NSConcreteMallocBlock);
		copy->flags++;

		if (block->flags & OF_BLOCK_HAS_COPY_DISPOSE)
			block->descriptor->copy_helper(copy, block);
		if (block->flags & OFBlockHasCopyDispose)
			block->descriptor->copyHelper(copy, block);

		return copy;
	}

	if ([(id)block isMemberOfClass: (Class)&_NSConcreteMallocBlock]) {
#ifdef OF_HAVE_ATOMIC_OPS
		of_atomic_int_inc(&block->flags);
		OFAtomicIntIncrease(&block->flags);
#else
		unsigned hash = SPINLOCK_HASH(block);

		OF_ENSURE(of_spinlock_lock(&blockSpinlocks[hash]) == 0);
		OFEnsure(OFSpinlockLock(&blockSpinlocks[hash]) == 0);
		block->flags++;
		OF_ENSURE(of_spinlock_unlock(&blockSpinlocks[hash]) == 0);
		OFEnsure(OFSpinlockUnlock(&blockSpinlocks[hash]) == 0);
#endif
	}

	return block;
}

void
_Block_release(const void *block_)
{
	of_block_literal_t *block = (of_block_literal_t *)block_;
	struct Block *block = (struct Block *)block_;

	if (object_getClass((id)block) != (Class)&_NSConcreteMallocBlock)
		return;

#ifdef OF_HAVE_ATOMIC_OPS
	if ((of_atomic_int_dec(&block->flags) & OF_BLOCK_REFCOUNT_MASK) == 0) {
		if (block->flags & OF_BLOCK_HAS_COPY_DISPOSE)
			block->descriptor->dispose_helper(block);
	if ((OFAtomicIntDecrease(&block->flags) & OFBlockRefCountMask) == 0) {
		if (block->flags & OFBlockHasCopyDispose)
			block->descriptor->disposeHelper(block);

		free(block);
	}
#else
	unsigned hash = SPINLOCK_HASH(block);

	OF_ENSURE(of_spinlock_lock(&blockSpinlocks[hash]) == 0);
	if ((--block->flags & OF_BLOCK_REFCOUNT_MASK) == 0) {
		OF_ENSURE(of_spinlock_unlock(&blockSpinlocks[hash]) == 0);
	OFEnsure(OFSpinlockLock(&blockSpinlocks[hash]) == 0);
	if ((--block->flags & OFBlockRefCountMask) == 0) {
		OFEnsure(OFSpinlockUnlock(&blockSpinlocks[hash]) == 0);

		if (block->flags & OF_BLOCK_HAS_COPY_DISPOSE)
			block->descriptor->dispose_helper(block);
		if (block->flags & OFBlockHasCopyDispose)
			block->descriptor->disposeHelper(block);

		free(block);

		return;
	}
	OF_ENSURE(of_spinlock_unlock(&blockSpinlocks[hash]) == 0);
	OFEnsure(OFSpinlockUnlock(&blockSpinlocks[hash]) == 0);
#endif
}

void
_Block_object_assign(void *dst_, const void *src_, const int flags_)
{
	int flags = flags_ & (OF_BLOCK_FIELD_IS_BLOCK |
	    OF_BLOCK_FIELD_IS_OBJECT | OF_BLOCK_FIELD_IS_BYREF);
	int flags = flags_ & (OFBlockFieldIsBlock | OFBlockFieldIsObject |
	    OFBlockFieldIsByref);

	if (src_ == NULL)
		return;

	switch (flags) {
	case OF_BLOCK_FIELD_IS_BLOCK:
		*(of_block_literal_t **)dst_ = _Block_copy(src_);
	case OFBlockFieldIsBlock:
		*(struct Block **)dst_ = _Block_copy(src_);
		break;
	case OF_BLOCK_FIELD_IS_OBJECT:
		if (!(flags_ & OF_BLOCK_BYREF_CALLER))
	case OFBlockFieldIsObject:
		if (!(flags_ & OFBlockByrefCaller))
			*(id *)dst_ = [(id)src_ retain];
		break;
	case OF_BLOCK_FIELD_IS_BYREF:;
		of_block_byref_t *src = (of_block_byref_t *)src_;
		of_block_byref_t **dst = (of_block_byref_t **)dst_;
	case OFBlockFieldIsByref:;
		struct Byref *src = (struct Byref *)src_;
		struct Byref **dst = (struct Byref **)dst_;

		src = src->forwarding;

		if ((src->flags & OF_BLOCK_REFCOUNT_MASK) == 0) {
		if ((src->flags & OFBlockRefCountMask) == 0) {
			if ((*dst = malloc(src->size)) == NULL) {
				alloc_failed_exception.isa =
				    [OFAllocFailedException class];
				@throw (OFAllocFailedException *)
				    &alloc_failed_exception;
			}

			memcpy(*dst, src, src->size);
			(*dst)->flags =
			    ((*dst)->flags & ~OF_BLOCK_REFCOUNT_MASK) | 1;
			    ((*dst)->flags & ~OFBlockRefCountMask) | 1;
			(*dst)->forwarding = *dst;

			if (src->flags & OF_BLOCK_HAS_COPY_DISPOSE)
				src->byref_keep(*dst, src);
			if (src->flags & OFBlockHasCopyDispose)
				src->keepByref(*dst, src);

#ifdef OF_HAVE_ATOMIC_OPS
			if (!of_atomic_ptr_cmpswap((void **)&src->forwarding,
			    src, *dst)) {
				src->byref_dispose(*dst);
			if (!OFAtomicPointerCompareAndSwap(
			    (void **)&src->forwarding, src, *dst)) {
				src->disposeByref(*dst);
				free(*dst);

				*dst = src->forwarding;
			}
#else
			unsigned hash = SPINLOCK_HASH(src);

			OF_ENSURE(of_spinlock_lock(&byrefSpinlocks[hash]) == 0);
			OFEnsure(OFSpinlockLock(&byrefSpinlocks[hash]) == 0);
			if (src->forwarding == src)
				src->forwarding = *dst;
			else {
				src->byref_dispose(*dst);
				src->disposeByref(*dst);
				free(*dst);

				*dst = src->forwarding;
			}
			OF_ENSURE(
			    of_spinlock_unlock(&byrefSpinlocks[hash]) == 0);
			OFEnsure(OFSpinlockUnlock(&byrefSpinlocks[hash]) == 0);
#endif
		} else
			*dst = src;

#ifdef OF_HAVE_ATOMIC_OPS
		of_atomic_int_inc(&(*dst)->flags);
		OFAtomicIntIncrease(&(*dst)->flags);
#else
		unsigned hash = SPINLOCK_HASH(*dst);

		OF_ENSURE(of_spinlock_lock(&byrefSpinlocks[hash]) == 0);
		OFEnsure(OFSpinlockLock(&byrefSpinlocks[hash]) == 0);
		(*dst)->flags++;
		OF_ENSURE(of_spinlock_unlock(&byrefSpinlocks[hash]) == 0);
		OFEnsure(OFSpinlockUnlock(&byrefSpinlocks[hash]) == 0);
#endif
		break;
	}
}

void
_Block_object_dispose(const void *object_, const int flags_)
{
	const int flags = flags_ & (OF_BLOCK_FIELD_IS_BLOCK |
	    OF_BLOCK_FIELD_IS_OBJECT | OF_BLOCK_FIELD_IS_BYREF);
	const int flags = flags_ & (OFBlockFieldIsBlock | OFBlockFieldIsObject |
	    OFBlockFieldIsByref);

	if (object_ == NULL)
		return;

	switch (flags) {
	case OF_BLOCK_FIELD_IS_BLOCK:
	case OFBlockFieldIsBlock:
		_Block_release(object_);
		break;
	case OF_BLOCK_FIELD_IS_OBJECT:
		if (!(flags_ & OF_BLOCK_BYREF_CALLER))
	case OFBlockFieldIsObject:
		if (!(flags_ & OFBlockByrefCaller))
			[(id)object_ release];
		break;
	case OF_BLOCK_FIELD_IS_BYREF:;
		of_block_byref_t *object = (of_block_byref_t *)object_;
	case OFBlockFieldIsByref:;
		struct Byref *object = (struct Byref *)object_;

		object = object->forwarding;

#ifdef OF_HAVE_ATOMIC_OPS
		if ((of_atomic_int_dec(&object->flags) &
		    OF_BLOCK_REFCOUNT_MASK) == 0) {
			if (object->flags & OF_BLOCK_HAS_COPY_DISPOSE)
				object->byref_dispose(object);
		if ((OFAtomicIntDecrease(&object->flags) &
		    OFBlockRefCountMask) == 0) {
			if (object->flags & OFBlockHasCopyDispose)
				object->disposeByref(object);

			free(object);
		}
#else
		unsigned hash = SPINLOCK_HASH(object);

		OF_ENSURE(of_spinlock_lock(&byrefSpinlocks[hash]) == 0);
		if ((--object->flags & OF_BLOCK_REFCOUNT_MASK) == 0) {
		OFEnsure(OFSpinlockLock(&byrefSpinlocks[hash]) == 0);
		if ((--object->flags & OFBlockRefCountMask) == 0) {
			OF_ENSURE(
			    of_spinlock_unlock(&byrefSpinlocks[hash]) == 0);
			OFEnsure(OFSpinlockUnlock(&byrefSpinlocks[hash]) == 0);

			if (object->flags & OF_BLOCK_HAS_COPY_DISPOSE)
				object->byref_dispose(object);
			if (object->flags & OFBlockHasCopyDispose)
				object->disposeByref(object);

			free(object);
		}
		OF_ENSURE(of_spinlock_unlock(&byrefSpinlocks[hash]) == 0);
		OFEnsure(OFSpinlockUnlock(&byrefSpinlocks[hash]) == 0);
#endif
		break;
	}
}

@implementation OFBlock
+ (void)load
{
#ifndef OF_HAVE_ATOMIC_OPS
	for (size_t i = 0; i < NUM_SPINLOCKS; i++)
		if (of_spinlock_new(&blockSpinlocks[i]) != 0 ||
		    of_spinlock_new(&byrefSpinlocks[i]) != 0)
	for (size_t i = 0; i < numSpinlocks; i++)
		if (OFSpinlockNew(&blockSpinlocks[i]) != 0 ||
		    OFSpinlockNew(&byrefSpinlocks[i]) != 0)
			@throw [OFInitializationFailedException
			    exceptionWithClass: self];
#endif

#ifdef OF_APPLE_RUNTIME
	Class tmp;

	return self;
}

- (unsigned int)retainCount
{
	if ([self isMemberOfClass: (Class)&_NSConcreteMallocBlock])
		return ((of_block_literal_t *)self)->flags &
		return ((struct Block *)self)->flags & OFBlockRefCountMask;
		    OF_BLOCK_REFCOUNT_MASK;

	return OF_RETAIN_COUNT_MAX;
	return OFMaxRetainCount;
}

- (void)release
{
	if ([self isMemberOfClass: (Class)&_NSConcreteMallocBlock])
		Block_release(self);
}

- (void)dealloc
{
	OF_DEALLOC_UNSUPPORTED
}
@end