static Class realizeClassWithoutSwift(Class cls){ runtimeLock.assertLocked(); const class_ro_t *ro; class_rw_t *rw; Class supercls; Class metacls; bool isMeta; if (!cls) return nil; if (cls->isRealized()) return cls; assert(cls == remapClass(cls)); // fixme verify class is not in an un-dlopened part of the shared cache? ro = (const class_ro_t *)cls->data(); if (ro->flags & RO_FUTURE) { // This was a future class. rw data is already allocated. rw = cls->data(); ro = cls->data()->ro; cls->changeInfo(RW_REALIZED|RW_REALIZING, RW_FUTURE); } else { // Normal class. Allocate writeable class data. rw = (class_rw_t *)calloc(sizeof(class_rw_t), 1); rw->ro = ro; rw->flags = RW_REALIZED|RW_REALIZING; cls->setData(rw); } isMeta = ro->flags & RO_META; rw->version = isMeta ? 7 : 0; // old runtime went up to 6 // Choose an index for this class. // Sets cls->instancesRequireRawIsa if indexes no more indexes are available cls->chooseClassArrayIndex(); if (PrintConnecting) { _objc_inform("CLASS: realizing class '%s'%s %p %p #%u %s%s", cls->nameForLogging(), isMeta ? " (meta)" : "", (void*)cls, ro, cls->classArrayIndex(), cls->isSwiftStable() ? "(swift)" : "", cls->isSwiftLegacy() ? "(pre-stable swift)" : ""); } // Realize superclass and metaclass, if they aren't already. // This needs to be done after RW_REALIZED is set above, for root classes. // This needs to be done after class index is chosen, for root metaclasses. // This assumes that none of those classes have Swift contents, // or that Swift's initializers have already been called. // fixme that assumption will be wrong if we add support // for ObjC subclasses of Swift classes. supercls = realizeClassWithoutSwift(remapClass(cls->superclass)); metacls = realizeClassWithoutSwift(remapClass(cls->ISA()));#if SUPPORT_NONPOINTER_ISA // Disable non-pointer isa for some classes and/or platforms. // Set instancesRequireRawIsa. bool instancesRequireRawIsa = cls->instancesRequireRawIsa(); bool rawIsaIsInherited = false; static bool hackedDispatch = false; if (DisableNonpointerIsa) { // Non-pointer isa disabled by environment or app SDK version instancesRequireRawIsa = true; } else if (!hackedDispatch && !(ro->flags & RO_META) && 0 == strcmp(ro->name, "OS_object")) { // hack for libdispatch et al - isa also acts as vtable pointer hackedDispatch = true; instancesRequireRawIsa = true; } else if (supercls && supercls->superclass && supercls->instancesRequireRawIsa()) { // This is also propagated by addSubclass() // but nonpointer isa setup needs it earlier. // Special case: instancesRequireRawIsa does not propagate // from root class to root metaclass instancesRequireRawIsa = true; rawIsaIsInherited = true; } if (instancesRequireRawIsa) { cls->setInstancesRequireRawIsa(rawIsaIsInherited); }// SUPPORT_NONPOINTER_ISA#endif // Update superclass and metaclass in case of remapping cls->superclass = supercls; cls->initClassIsa(metacls); // Reconcile instance variable offsets / layout. // This may reallocate class_ro_t, updating our ro variable. if (supercls && !isMeta) reconcileInstanceVariables(cls, supercls, ro); // Set fastInstanceSize if it wasn't set already. cls->setInstanceSize(ro->instanceSize); // Copy some flags from ro to rw if (ro->flags & RO_HAS_CXX_STRUCTORS) { cls->setHasCxxDtor(); if (! (ro->flags & RO_HAS_CXX_DTOR_ONLY)) { cls->setHasCxxCtor(); } } // Propagate the associated objects forbidden flag from ro or from // the superclass. if ((ro->flags & RO_FORBIDS_ASSOCIATED_OBJECTS) || (supercls && supercls->forbidsAssociatedObjects())) { rw->flags |= RW_FORBIDS_ASSOCIATED_OBJECTS; } // Connect this class to its superclass's subclass lists if (supercls) { addSubclass(supercls, cls); } else { addRootClass(cls); } // Attach categories methodizeClass(cls); return cls;}抽取此中部分
ro = (const class_ro_t *)cls->data(); if (ro->flags & RO_FUTURE) { // This was a future class. rw data is already allocated. rw = cls->data(); ro = cls->data()->ro; cls->changeInfo(RW_REALIZED|RW_REALIZING, RW_FUTURE); } else { // Normal class. Allocate writeable class data. rw = (class_rw_t *)calloc(sizeof(class_rw_t), 1); rw->ro = ro; rw->flags = RW_REALIZED|RW_REALIZING; cls->setData(rw); }
; if (!lookUpImpOrNil(inst,resolve_sel,cls->ISA())){ // Resolver not implemented. return; } BOOL (*msg)(class,SEL,SEL) = (typeof(msg))objc_msgSend; bool resolved = msg(cls,resolve_sel,oldSel); // 假如决议一次之后没有找到，继承lookUpImpOrForward(二分遍历当前类和全部父类),末了实行消息转发 IMP imp = lookUpImpOrNil(inst,oldSel,cls); if (resolved && PrintResolveing){ if (imp){ _objc_inform("RESOLVE: method %c[%s %s]""bynamically resolveed to %p", cls->isMetaClass()?'+':'-', cls->nameForLogging(), sel_getName(oldSel), imp); } else { _objc_inform("RESOLVE: +[%s resolveInstanceMethod:%s] returned YES" ",but no new implementation of %c[%s %s] was found", cls->nameForLogging(),sel_getName(oldSel), cls->isMetaClass()?'+':'-', cls->nameForLogging(),sel_getName(oldSel)); } } }resolveMethod_locked 有什么用??
SEL)sel{ if (sel == @selector(cxxxx)){ // 添加方法 IMP imp = class_getMethodImplementation(self,@selector(kxxxx)); Method met = class_getInstanceMethod(self,@selector(kxxxx)); const char *type = method_getTypeEncoding(mit); BOOL hasWhy = class_addMethod(self,sel,type); } return [super resolveInstanceMethod:sel];}
"RC"])return NO; // 只处理惩罚自己界说的方法 // 对象方法处理惩罚 const char * cx = "cxxxx"; if (sel_getName(sel) == cx){ // 添加方法 IMP imp = class_getMethodImplementation(self,@selector(kxxxx)); Method met = class_getInstanceMethod(self,@selector(kxxxx)); const char *type = method_getTypeEncoding(met); BOOL hasWhy = class_addMethod(self, sel, imp, type); return NO; } // 类方法处理惩罚 const char * sx = "sxxxx"; if (sel_getName(sel) == sx){ // 添加方法 Class currenrClass = objc_getMetaClass("RCPerson"); IMP imp = class_getMethodImplementation(currenrClass,@selector(zxxxx)); Method met = class_getInstanceMethod(currenrClass,@selector(zxxxx)); const char *type = method_getTypeEncoding(met); BOOL hasWhy = class_addMethod(currenrClass, sel, imp, type); return NO; } return NO;}假如没有使用resolveInstanceMethod动态决议呢？？(此时imp便是forawrd_imp)
