Created attachment 279018 [details] [review]
gsocketlistener: Mention socket close behaviour in documentation

Expand the documentation for g_socket_listener_add_socket() to make it
clear that the GSocketListener will close the socket when the listener
is finalised, even if the caller retains a reference to the GSocket.

Hmm, although, this behaviour is a little counter-intuitive. Perhaps it would be better to remove the explicit g_socket_listener_close() call from g_socket_listener_finalize, and rely on the GSockets closing themselves when their last reference is dropped. That would allow use of temporary GSocketListeners to automatically create IPv4 and IPv6 sockets for a given port (using g_socket_listener_add_inet_port()), the calling code to grab them using g_socket_listener_get_sockets() (bug #584257), then the GSocketListener to be finalised because it isn’t needed any more, and the sockets themselves to live on.

That would not be a behaviour change for sockets added internally by the GSocketListener (because no other code can ever access them to take a reference). It could be a behaviour change for sockets added with g_socket_listener_add_socket(), if the user then finalises the GSocketListener (without explicitly calling g_socket_listener_close()) and expects the sockets to be closed at the same time. I think that’s a bit of a weird case, though.

The GSocketListener documentation never previously guaranteed that GSockets were closed on finalisation, so I think it would be OK to remove the g_socket_listener_close() call from g_socket_listener_finalize().

Created attachment 279021 [details] [review]
gsocketlistener: Don’t explicitly close sockets on finalisation

Instead of closing the sockets explicitly, let them close themselves
when their final reference is dropped. This makes use of
g_socket_listener_add_socket() more natural.

Comment on attachment 279021 [details] [review]
gsocketlistener: Don’t explicitly close sockets on finalisation

Yes, this is consistent with GSocketConnection (which used to explicitly close its socket on dispose, but now does not).

You should add a comment to g_socket_listener_add_socket() though, both explaining the behavior, and explaining that it didn't work that way before 2.42.

>+   * g_socket_listener_add_socket() was used). */
>   g_ptr_array_free (listener->priv->sockets, TRUE);

nitpick; multi-line comment style in glib generally puts the closing "*/" on its own line.

Created attachment 279051 [details] [review]
gsocketlistener: Don’t explicitly close sockets on finalisation

Instead of closing the sockets explicitly, let them close themselves
when their final reference is dropped. This makes use of
g_socket_listener_add_socket() more natural.

Comment on attachment 279051 [details] [review]
gsocketlistener: Don’t explicitly close sockets on finalisation

commit f1095de46f5f43edf494ea6adcabbe86685baadf
Author: Philip Withnall <philip.withnall@collabora.co.uk>
Date:   Mon Jun 23 15:01:28 2014 +0100

    gsocketlistener: Don’t explicitly close sockets on finalisation
    
    Instead of closing the sockets explicitly, let them close themselves
    when their final reference is dropped. This makes use of
    g_socket_listener_add_socket() more natural.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=732107

 gio/gsocketlistener.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)