Re: [gtk-list] Re: g_malloc() aborts when enough memory is notfound?

["Emmanuel DELOGET" <logout free fr>]

> On Tue, 2 Nov 1999, Emmanuel DELOGET wrote:
>
> >
> >     Hi Owen,
> >
> >     I don't know if this is a good idea. If it is possible
> >     to extend the callback architecture to glib (for version
> >     1.30, perhaps :)), the abort behavior should be avoided in
> >     some cases. Consider the following (in a multiple window
> >     text processor)
>
> g_malloc() is used in a *lot* of places (usually *everywhere* in gtk/gnome
> programs where dynamic allocations are required). most (i.e. 99.999%) of
> these places do *not* check for NULL because g_malloc() is documented
> to never return NULL.
> so a global flag is probably *not* appropriate here.

    When I was studying 3 years ago, we developped an allocator library
    with multiple global allocation schemes : abort-on-no-mem,
    stand-by-on-no-mem, and so on, with a simple allocator object which
    could look like this:

    struct _GAllocator
    {
        gpointer (*g_malloc_func)(size_t);
        void (*g_free_func)(gpointer pointer);
        size_t allocated_space;
        /* additional fields should helps for other tasks */
    };

    With this scheme, you can create virtually any type of allocator (debug,
retail, ...).
    Then you'll need some misc functions such as :

    gpointer gallocator_alloc(GAllocator *, size_t);
    void gallocator_free(GAllocator *, gpointer);

    You can create a glib_normal_alloc that suits the current glib behavior,
and
    redefine g_malloc() to be

#define g_malloc(s)        gallocator_alloc(glib_normal_alloc, (s))
#define g_free(p)            gallocator_free(glib_normal_alloc, (p))

    So you do not need to modify any current gtk/gnome based component, and
    you can safely implement a new allocator.

> out of curiosity, how do you popup a dialog if there's no memory
available?

    The dialog is created during the init. You also create the label you
need
    (so there is no need for a malloc when you have to show the dialog).

> >     Emmanuel
> ---
> ciaoTJ