4d326182 changed connection hashing slightly such that now base type settings
are always returned even if they are empty. Unfortunately a bunch of code in
the settings hashed connections with the ONLY_SECRETS flag and then checked
whether the returned hash was NULL or not to determine whether there were
any secrets, and then called nm_connection_update_secrets() with the hash.
nm_connection_update_secrets() would fail in the case where a setting
name was given, but the passed-in secrets hash did not contain any secrets
for the requested setting. Instead, the function should return success
to match the semantics of passing in an entire connection hash which may
not have any secrets either.
GObject creation cannot normally fail, except for types that implement
GInitable and take a GError in their _new() method. Some NM types
override constructor() and return NULL in some cases, but these
generally only happen in the case of programmer error (eg, failing to
set a mandatory property), and so crashing is reasonable (and most
likely inevitable anyway).
So, remove all NULL checks after calls to g_object_new() and its
myriad wrappers.
https://bugzilla.gnome.org/show_bug.cgi?id=693678
The core problem was that the Update would trigger a write to
disk to save the connection's new settings, which called
nm_settings_connection_replace_settings(). Which saved existing
transient (agent/unsaved) secrets, replaced settings with the
new ones from Update(), then copied back the old transient
secrets. This was to ensure that changes triggered from getting
agent secrets during activation (which might write the connection
out to disk if new system secrets were provided, which triggered
an inotify read-back of the connection, which blew away the
transient secrets just returned from the agent) didn't blow away
transient secrets. Unfortunately that fix was too general.
As a quick hack for now, copy the new secrets and re-apply them
after nm_connection_replace_settings() has run. We'll do the
actual fix later, but it's more involved and needs more testing
so we don't want to apply it this close to release.
It's easier to be able to pass both a whole hashed connection, or just
a hashed setting to the function, and have it figure out what needs
to be updated based on the given setting_name.
Add some testcases to make sure that all works correctly too.
