Method class_getInstanceMethod(Class aClass, SEL aSelector)
{
CHECK_ARG(aClass);
CHECK_ARG(aSelector);
// If the class has a dtable installed, then we can use the fast path
if (classHasInstalledDtable(aClass))
{
// Do a dtable lookup to find out which class the method comes from.
struct objc_slot *slot = objc_get_slot(aClass, aSelector);
if (NULL == slot)
{
slot = objc_get_slot(aClass, sel_registerName(sel_getName(aSelector)));
if (NULL == slot)
{
return NULL;
}
}
// Now find the typed variant of the selector, with the correct types.
aSelector = slot->selector;
// Then do the slow lookup to find the method.
return class_getInstanceMethodNonrecursive(slot->owner, aSelector);
}
Method m = class_getInstanceMethodNonrecursive(aClass, aSelector);
if (NULL != m)
{
return m;
}
return class_getInstanceMethod(class_getSuperclass(aClass), aSelector);
}
static void objc_updateDtableForClassContainingMethod(Method m)
{
Class nextClass = Nil;
void *state = NULL;
SEL sel = method_getName(m);
while (Nil != (nextClass = objc_next_class(&state)))
{
if (class_getInstanceMethodNonrecursive(nextClass, sel) == m)
{
objc_update_dtable_for_class(nextClass);
return;
}
}
}
IMP
class_replaceMethod(Class cls, SEL name, IMP imp, const char *types)
{
Method method = class_getInstanceMethodNonrecursive(cls, name);
IMP old;
if (method == NULL)
{
class_addMethod(cls, name, imp, types);
return NULL;
}
old = (IMP) method->method_imp;
method->method_imp = (objc_imp_gnu) imp;
return old;
}
Method
class_getInstanceMethod(Class aClass, SEL aSelector)
{
Method method = class_getInstanceMethodNonrecursive(aClass, aSelector);
if (method == NULL)
{
// TODO: Check if this should be NULL or aClass
Class superclass = class_getSuperclass(aClass);
if (superclass == NULL)
{
return NULL;
}
return class_getInstanceMethod(superclass, aSelector);
}
return method;
}
IMP class_replaceMethod(Class cls, SEL name, IMP imp, const char *types)
{
if (Nil == cls) { return (IMP)0; }
SEL sel = sel_registerTypedName_np(sel_getName(name), types);
Method method = class_getInstanceMethodNonrecursive(cls, sel);
if (method == NULL)
{
class_addMethod(cls, sel, imp, types);
return NULL;
}
IMP old = (IMP)method->imp;
method->imp = imp;
if (objc_test_class_flag(cls, objc_class_flag_resolved))
{
objc_update_dtable_for_class(cls);
}
return old;
}
