ObjFW  Artifact [107b957fe8]

Artifact 107b957fe85aaebc9e2f4819545f8e5fec651cade5c03b11513cd0ca111825c3:

• File src/runtime/lookup.m — part of check-in [fe2cbe0021] at 2018-04-22 16:13:04 on branch trunk — runtime: Define BOOL to be the same as bool

  As we define the ABI, we can just replace BOOL with bool everywhere,
  including in ObjFW itself. For the Apple platforms where BOOL and bool
  are different, this is not a problem as BOOL and bool are passed and
  returned the same way in the ABI.

  This still defines BOOL to bool for compatibility, except on AmigaOS and
  Wii, which both have its own BOOL type. (user: js, size: 4681) [annotate] [blame] [check-ins using] [more...]

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017,
 *               2018
 *   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.
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>

#import "ObjFW_RT.h"
#import "private.h"
#import "macros.h"

@interface DummyObject
{
	Class isa;
}

+ (bool)resolveClassMethod: (SEL)selector;
+ (bool)resolveInstanceMethod: (SEL)selector;
@end

static IMP forward_handler = (IMP)0;
static IMP forward_handler_stret = (IMP)0;

static IMP
common_method_not_found(id obj, SEL sel, IMP (*lookup)(id, SEL), IMP forward)
{
	/*
	 * obj might be a dummy object (see class_getMethodImplementation), so
	 * don't access obj directly unless it's a class!
	 */

	bool is_class = object_getClass(obj)->info & OBJC_CLASS_INFO_METACLASS;

	if (!(object_getClass(obj)->info & OBJC_CLASS_INFO_INITIALIZED)) {
		Class cls = (is_class ? (Class)obj : object_getClass(obj));

		objc_initialize_class(cls);

		if (!(cls->info & OBJC_CLASS_INFO_SETUP))
			OBJC_ERROR("Could not dispatch message for incomplete "
			    "class %s!", cls->name);

		/*
		 * We don't need to handle the case that super was called.
		 * The reason for this is that a call to super is not possible
		 * before a message to the class has been sent and it thus has
		 * been initialized together with its superclasses.
		 */
		return lookup(obj, sel);
	}

	/* Try resolveClassMethod: / resolveInstanceMethod: */
	if (class_isMetaClass(object_getClass(obj))) {
		Class cls = object_getClass(obj);

		if (class_respondsToSelector(cls,
		    @selector(resolveClassMethod:)) &&
		    [obj resolveClassMethod: sel]) {
			if (!class_respondsToSelector(cls, sel))
				OBJC_ERROR("[%s resolveClassMethod: %s] "
				    "returned true without adding the method!",
				    class_getName(obj), sel_getName(sel));

			return lookup(obj, sel);
		}
	} else {
		Class cls = object_getClass(obj);
		Class metacls = object_getClass(cls);

		if (class_respondsToSelector(metacls,
		    @selector(resolveInstanceMethod:)) &&
		    [cls resolveInstanceMethod: sel]) {
			if (!class_respondsToSelector(cls, sel))
				OBJC_ERROR("[%s resolveInstanceMethod: %s] "
				    "returned true without adding the method!",
				    class_getName(object_getClass(obj)),
				    sel_getName(sel));

			return lookup(obj, sel);
		}
	}

	if (forward != (IMP)0)
		return forward;

	OBJC_ERROR("Selector %c[%s] is not implemented for class %s!",
	    (is_class ? '+' : '-'), sel_getName(sel), object_getClassName(obj));
}

IMP
objc_method_not_found(id obj, SEL sel)
{
	return common_method_not_found(obj, sel, objc_msg_lookup,
	    forward_handler);
}

IMP
objc_method_not_found_stret(id obj, SEL sel)
{
	return common_method_not_found(obj, sel, objc_msg_lookup_stret,
	    forward_handler_stret);
}

void
objc_setForwardHandler(IMP forward, IMP forward_stret)
{
	forward_handler = forward;
	forward_handler_stret = forward_stret;
}

bool
class_respondsToSelector(Class cls, SEL sel)
{
	if (cls == Nil)
		return false;

	return (objc_dtable_get(cls->dtable, (uint32_t)sel->uid) != (IMP)0);
}

#ifndef OF_ASM_LOOKUP
static id
nil_method(id self, SEL _cmd)
{
	return nil;
}

static OF_INLINE IMP
common_lookup(id obj, SEL sel, IMP (*not_found)(id, SEL))
{
	IMP imp;

	if (obj == nil)
		return (IMP)nil_method;

	imp = objc_dtable_get(object_getClass(obj)->dtable, (uint32_t)sel->uid);

	if (imp == (IMP)0)
		return not_found(obj, sel);

	return imp;
}

IMP
objc_msg_lookup(id obj, SEL sel)
{
	return common_lookup(obj, sel, objc_method_not_found);
}

IMP
objc_msg_lookup_stret(id obj, SEL sel)
{
	return common_lookup(obj, sel, objc_method_not_found_stret);
}

static OF_INLINE IMP
common_lookup_super(struct objc_super *super, SEL sel,
    IMP (*not_found)(id, SEL))
{
	IMP imp;

	if (super->self == nil)
		return (IMP)nil_method;

	imp = objc_dtable_get(super->cls->dtable, (uint32_t)sel->uid);

	if (imp == (IMP)0)
		return not_found(super->self, sel);

	return imp;
}

IMP
objc_msg_lookup_super(struct objc_super *super, SEL sel)
{
	return common_lookup_super(super, sel, objc_method_not_found);
}

IMP
objc_msg_lookup_super_stret(struct objc_super *super, SEL sel)
{
	return common_lookup_super(super, sel, objc_method_not_found_stret);
}
#endif