_gio_module_get_default() is a very convenient function for modules
implementing a singleton -- it finds the default module by priority
subject to override by a given environment variable name, instantiates
it, and caches the instance for future calls. It also has the ability
to query instances for being 'active' using a callback.
It doesn't work very well for non-singletons (like file monitors).
Add a new function _gio_module_get_default_type() that skips the
instantiation, returning the GType instead. As a replacement for the
'active' callback, a vtable offset can be given for a virtual function
to use to query if a particular backend is supported.
https://bugzilla.gnome.org/show_bug.cgi?id=592211
Add _g_io_module_get_default(), which implements the
figure-out-the-best-available-module-that-is-actually-usable logic,
and use that to simplify g_proxy_resolver_get_default(),
g_settings_backend_get_default(), g_tls_backend_get_default(), and
g_vfs_get_default().
https://bugzilla.gnome.org/show_bug.cgi?id=620932
2009-02-27 Alexander Larsson <alexl@redhat.com>
* giomodule-priv.h:
* giomodule.c:
Split out the extension point registration code to its
own function.
* glocalvfs.c:
Ensure extension points are registered before extending it.
It might not have happened yet if g_vfs_get_local() is called.
svn path=/trunk/; revision=7919
