Re: [2/2] server: A being destroyed object may need to access other objects using a handle.

[Alexandre Julliard]

Dmitry Timoshkov <dmitry(a)baikal.ru> writes:
> --- a/server/handle.c
> +++ b/server/handle.c
> @@ -165,7 +165,6 @@ static void handle_table_destroy( struct object *obj )
>      for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
>      {
>          struct object *obj = entry->ptr;
> -        entry->ptr = NULL;
>          if (obj) release_object( obj );

You can't do that, the object can't be accessed after being released.

-- 
Alexandre Julliard
julliard(a)winehq.org

[2/2] server: A being destroyed object may need to access other objects using a handle.

[Dmitry Timoshkov]

Alexandre Julliard <julliard(a)winehq.org> wrote:
> > --- a/server/handle.c
> > +++ b/server/handle.c
> > @@ -165,7 +165,6 @@ static void handle_table_destroy( struct object *obj )
> >      for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
> >      {
> >          struct object *obj = entry->ptr;
> > -        entry->ptr = NULL;
> >          if (obj) release_object( obj );
>
> You can't do that, the object can't be accessed after being released.

Being released doesn't mean destroyed. An object gets destroyed only if its
refcount drops to 0.

-- 
Dmitry.

[2/2] server: A being destroyed object may need to access other objects using a handle.

[Alexandre Julliard]

Dmitry Timoshkov <dmitry(a)baikal.ru> writes:
> Alexandre Julliard <julliard(a)winehq.org> wrote:
> > > --- a/server/handle.c
> > > +++ b/server/handle.c
> > > @@ -165,7 +165,6 @@ static void handle_table_destroy( struct object *obj )
> > >      for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
> > >      {
> > >          struct object *obj = entry->ptr;
> > > -        entry->ptr = NULL;
> > >          if (obj) release_object( obj );
> >
> > You can't do that, the object can't be accessed after being released.
>
> Being released doesn't mean destroyed. An object gets destroyed only if its
> refcount drops to 0.

Obviously, but in general the handle will be the only reference.

-- 
Alexandre Julliard
julliard(a)winehq.org

[2/2] server: A being destroyed object may need to access other objects using a handle.

[Dmitry Timoshkov]

Alexandre Julliard <julliard(a)winehq.org> wrote:
> > > > --- a/server/handle.c
> > > > +++ b/server/handle.c
> > > > @@ -165,7 +165,6 @@ static void handle_table_destroy( struct object *obj )
> > > >      for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
> > > >      {
> > > >          struct object *obj = entry->ptr;
> > > > -        entry->ptr = NULL;
> > > >          if (obj) release_object( obj );
> > >
> > > You can't do that, the object can't be accessed after being released.
> >
> > Being released doesn't mean destroyed. An object gets destroyed only if its
> > refcount drops to 0.
>
> Obviously, but in general the handle will be the only reference.

Then I don't understand what you mean regarding the code snippet above.

-- 
Dmitry.

[2/2] server: A being destroyed object may need to access other objects using a handle.

[Alexandre Julliard]

Dmitry Timoshkov <dmitry(a)baikal.ru> writes:
> Alexandre Julliard <julliard(a)winehq.org> wrote:
> > > > > --- a/server/handle.c
> > > > > +++ b/server/handle.c
> > > > > @@ -165,7 +165,6 @@ static void handle_table_destroy( struct object *obj )
> > > > >      for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
> > > > >      {
> > > > >          struct object *obj = entry->ptr;
> > > > > -        entry->ptr = NULL;
> > > > >          if (obj) release_object( obj );
> > > >
> > > > You can't do that, the object can't be accessed after being released.
> > >
> > > Being released doesn't mean destroyed. An object gets destroyed only if its
> > > refcount drops to 0.
> >
> > Obviously, but in general the handle will be the only reference.
>
> Then I don't understand what you mean regarding the code snippet above.

After release_object, the object will have been freed if this was the
last reference. You can't keep a pointer to it.

-- 
Alexandre Julliard
julliard(a)winehq.org

[2/2] server: A being destroyed object may need to access other objects using a handle.

[Dmitry Timoshkov]

Alexandre Julliard <julliard(a)winehq.org> wrote:
> > > > > > --- a/server/handle.c
> > > > > > +++ b/server/handle.c
> > > > > > @@ -165,7 +165,6 @@ static void handle_table_destroy( struct object *obj )
> > > > > >      for (i = 0, entry = table->entries; i <= table->last; i++, entry++)
> > > > > >      {
> > > > > >          struct object *obj = entry->ptr;
> > > > > > -        entry->ptr = NULL;
> > > > > >          if (obj) release_object( obj );
> > > > >
> > > > > You can't do that, the object can't be accessed after being released.
> > > >
> > > > Being released doesn't mean destroyed. An object gets destroyed only if its
> > > > refcount drops to 0.
> > >
> > > Obviously, but in general the handle will be the only reference.
> >
> > Then I don't understand what you mean regarding the code snippet above.
>
> After release_object, the object will have been freed if this was the
> last reference. You can't keep a pointer to it.

If you know how to fix this properly - please go ahead, I won't be able
to investigate this till next week.

-- 
Dmitry.