Re: [pygame] Surfarray.array_alpha() bugfix, py2exe/py2app segfault

[Lenard Lindstrom <len-l@xxxxxxxxx>]

René Dudfield wrote:
> On Tue, Feb 3, 2009 at 7:11 PM, Marcus von Appen <mva@xxxxxxxxxxxx> wrote:
>   
> > On, Tue Feb 03, 2009, Lenard Lindstrom wrote:
> >     
> [cut]
>   
> > > Well, for starters the buffer proxy object only borrows a reference to
> > > its parent surface (no PY_INCREF/PY_DECREF calls).
> > >       
> > Which should be absolutely okay, as surface.get_buffer() acquires a
> > lock.
> >
> >     
>
> hrmm... I think it could matter if the parent surface gets to
> reference count 0 -- when the buffer still exists, and then the
> surface tries to deallocate the parent surface memory... thus making
> the buffer point to invalid memory.
>
> ?
>   
No, Marcus is right. I missed the whole lifetime lock thing. The buffer 
proxy does acquire a new reference to its parent surface via the lock 
object. But in verifying this I did find a potential memory leak in 
surflock's PySurface_LockLifetime, unrelated to the problem at hand 
though. Otherwise reference counting looks to be in order. That leaves 
_numpysurfarray.py.

Lenard

--
Lenard Lindstrom
<len-l@xxxxxxxxx>