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improve forwarding hook usage

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git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/libobjc/trunk@32631 72102866-910b-0410-8b05-ffd578937521
main
rfm 15 years ago
parent e1032243ac
commit 242d634164
1 changed files with 75 additions and 58 deletions
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133
sendmsg.c
Unescape Escape View File

@ -109,7 +109,7 @@ __objc_get_forward_imp (id rcv, SEL sel)
{
IMP result;
if ((result = __objc_msg_forward (sel)) != NULL)
return result;
return result;
}
/* In all other cases, use the default forwarding functions built using
@ -139,7 +139,74 @@ __objc_get_forward_imp (id rcv, SEL sel)
Since this requires the dispatch table to be installed, this function
will implicitly invoke +initialize for CLASS if it hasn't been
invoked yet. This also insures that +initialize has been invoked
when the returned implementation is called directly. */
when the returned implementation is called directly.
The forwarding hooks require the receiver as an argument (if they are to
perform dynamic lookup in proxy objects etc), so this function has a
receiver argument to be used with those hooks. */
static inline
IMP
get_implementation (id receiver, Class class, SEL sel)
{
void *res;
if (class->dtable == __objc_uninstalled_dtable)
{
/* The dispatch table needs to be installed. */
objc_mutex_lock (__objc_runtime_mutex);
/* Double-checked locking pattern: Check
__objc_uninstalled_dtable again in case another thread
installed the dtable while we were waiting for the lock
to be released. */
if (class->dtable == __objc_uninstalled_dtable)
__objc_install_dtable_for_class (class);
/* If the dispatch table is not yet installed,
we are still in the process of executing +initialize.
But the implementation pointer should be avaliable
if it exists at all. */
if (class->dtable == __objc_uninstalled_dtable)
{
assert (__objc_prepared_dtable_for_class (class) != 0);
res = __objc_get_prepared_imp (class, sel);
}
else
{
res = 0;
}
objc_mutex_unlock (__objc_runtime_mutex);
/* Call ourselves with the installed dispatch table
and get the real method */
if (! res)
res = get_implementation (receiver, class, sel);
}
else
{
/* The dispatch table has been installed. */
/* Get the method from the dispatch table (we try to get it
again in case another thread has installed the dtable just
after we invoked sarray_get_safe, but before we checked
class->dtable == __objc_uninstalled_dtable).
*/
res = sarray_get_safe (class->dtable, (size_t) sel->sel_id);
if (res == 0)
{
/* The dispatch table has been installed, and the method
is not in the dispatch table. So the method just
doesn't exist for the class. Return the forwarding
implementation.
We don't know the receiver (only it's class), so we
can't pass that to the function :-(
*/
res = __objc_get_forward_imp (receiver, sel);
}
}
return res;
}
inline
IMP
get_imp (Class class, SEL sel)
@ -155,57 +222,7 @@ get_imp (Class class, SEL sel)
void *res = sarray_get_safe (class->dtable, (size_t) sel->sel_id);
if (res == 0)
{
/* Not a valid method */
if (class->dtable == __objc_uninstalled_dtable)
{
/* The dispatch table needs to be installed. */
objc_mutex_lock (__objc_runtime_mutex);
/* Double-checked locking pattern: Check
__objc_uninstalled_dtable again in case another thread
installed the dtable while we were waiting for the lock
to be released. */
if (class->dtable == __objc_uninstalled_dtable)
__objc_install_dtable_for_class (class);
/* If the dispatch table is not yet installed,
we are still in the process of executing +initialize.
But the implementation pointer should be avaliable
if it exists at all. */
if (class->dtable == __objc_uninstalled_dtable)
{
assert (__objc_prepared_dtable_for_class (class) != 0);
res = __objc_get_prepared_imp (class, sel);
}
objc_mutex_unlock (__objc_runtime_mutex);
/* Call ourselves with the installed dispatch table
and get the real method */
if (! res)
res = get_imp (class, sel);
}
else
{
/* The dispatch table has been installed. */
/* Get the method from the dispatch table (we try to get it
again in case another thread has installed the dtable just
after we invoked sarray_get_safe, but before we checked
class->dtable == __objc_uninstalled_dtable).
*/
res = sarray_get_safe (class->dtable, (size_t) sel->sel_id);
if (res == 0)
{
/* The dispatch table has been installed, and the method
is not in the dispatch table. So the method just
doesn't exist for the class. Return the forwarding
implementation.
We don't know the receiver (only it's class), so we
can't pass that to the function :-(
*/
res = __objc_get_forward_imp (nil, sel);
}
}
res = get_implementation(nil, class, sel);
}
return res;
}
@ -264,7 +281,7 @@ objc_msg_lookup (id receiver, SEL op)
(sidx)op->sel_id);
if (result == 0)
{
result = get_imp(receiver->class_pointer, op);
result = get_implementation(receiver, receiver->class_pointer, op);
}
return result;
}
@ -586,7 +603,7 @@ __objc_forward (id object, SEL sel, arglist_t args)
if (__objc_responds_to (object, frwd_sel))
{
imp = get_imp (object->class_pointer, frwd_sel);
imp = get_implementation (object, object->class_pointer, frwd_sel);
return (*imp) (object, frwd_sel, sel, args);
}
@ -595,7 +612,7 @@ __objc_forward (id object, SEL sel, arglist_t args)
err_sel = sel_get_any_uid ("doesNotRecognize:");
if (__objc_responds_to (object, err_sel))
{
imp = get_imp (object->class_pointer, err_sel);
imp = get_implementation (object, object->class_pointer, err_sel);
return (*imp) (object, err_sel, sel);
}
@ -614,7 +631,7 @@ __objc_forward (id object, SEL sel, arglist_t args)
err_sel = sel_get_any_uid ("error:");
if (__objc_responds_to (object, err_sel))
{
imp = get_imp (object->class_pointer, err_sel);
imp = get_implementation (object, object->class_pointer, err_sel);
return (*imp) (object, sel_get_any_uid ("error:"), msg);
}
@ -669,7 +686,7 @@ objc_get_uninstalled_dtable ()
static cache_ptr prepared_dtable_table = 0;
/* This function is called by:
get_imp and __objc_responds_to
get_implementation and __objc_responds_to
(and the dispatch table installation functions themselves)
to install a dispatch table for a class.

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