• Joe Clarke's avatar
    remove watch on fd when reaching EOF · a7e5318b
    Joe Clarke authored
    On Wed, 2008-04-30 at 16:30 -0400, David Zeuthen wrote:
    > On Wed, 2008-04-30 at 16:21 -0400, Joe Marcus Clarke wrote:
    > > David Zeuthen wrote:
    > > > On Wed, 2008-04-30 at 13:52 -0400, Joe Marcus Clarke wrote:
    > > >> David Zeuthen wrote:
    > > >>> On Wed, 2008-04-30 at 13:44 -0400, Joe Marcus Clarke wrote:
    > > >>>> Correct.  I think it does read all the data, then the stream puts out
    > > >>>> EOF which causes the helper to be called ad infinitum.
    > > >>> I see. Mmm.. In that case, polkit_grant_io_func() can detect EOF
    > > >>> (getline() returning -1) and then call the remove_watch() method
    > > >>> supplied by polkit-gnome-manager.c right?
    > > >> It could, but what's the difference between that and returning FALSE in
    > > >> the caller?  Both would result in the watch being removed.  And since
    > > >> the io_func reads the entire amount of data (until EOF) that shouldn't
    > > >> be a problem.
    > > >
    > > > The PAM conversation happens over that fd and for some cases I don't
    > > > think we read all the data at once. So there may be multiple calls to
    > > > polkit_grant_io_func(). As such, returning FALSE won't work for all
    > > > cases.
    > >
    > > It looks like it will (read all data).  The polkit_grant_io_func() runs
    > > in a while loop waiting for readline to return -1.  I don't see that
    > > this function ever returns to the caller until readline returns -1
    > > (signifying EOF or some other error).  Am I misunderstanding something?
    >
    > No, you're right, that's how it works right now. But in the future this
    > function might return control back to the application and then it needs
    > to be called again by the watch when the application goes to process the
    > main loop.
    >
    > Anyway, the other main reason I'd like polkit_grant_io_func() to call
    > remove_watch() as opposed to making io_watch_have_data() in
    > polkit-gnome-manager.c return FALSE is because of the fact that
    > PolicyKit-gnome is just one of many users of libpolkit-grant (others
    > right now are: polkit-auth(1), the PolicyKit-kde project that some
    > people are working on)
    
    That works.  Adding this hunk to polkit-grant.c fixes the problem:
    
    @@ -419,6 +420,8 @@ polkit_grant_io_func (PolKitGrant *polki
    
             if (line != NULL)
                     free (line);
    +
    +        polkit_grant->func_remove_watch (polkit_grant, polkit_grant->io_watch_id);
     }
    
     /**
    
    Joe
    a7e5318b
polkit-grant.c 20.3 KB