NMDevice's act_stage1_prepare() now does nothing. Calling it is not
useful and has no effect.
In general, when a subclass overwrites a virtual function, it must be
defined whether the subclass must, may or must-not call the parents
implementation. Likewise, it must be clear when the parents
implementation should be chained: first, as last, does it matter?
In any case, that very much depends on how the parent is implemented
and this can only be solved by documentation and common conventions.
It's a forgiving approach to have a parents implementation do nothing,
then the subclass may call it at any time (or not call it at all).
This is especially useful if classes don't know their parent class well.
But in NetworkManager code the relationship between classes are known
at compile time, so every of these classes knows it derives directly
from NMDevice.
This forgingin approach was what NMDevice's act_stage1_prepare() was doing.
However, it also adds lines of code resulting in a different kind of complexity.
So, it's not clear that this forgiving approach is really better. Note
that it also has a (tiny) runtime and code-size overhead.
Change the expectation of how NMDevice's act_stage1_prepare() should be
called: it is no longer implemented, and subclasses *MUST* not chain up.
In the past, the headers "linux/if.h" and "net/if.h" were incompatible.
That means, we can either include one or the other, but not both.
This is fixed in the meantime, however the issue still exists when
building against older kernel/glibc.
That means, including one of these headers from a header file
is problematic. In particular if it's a header like "nm-platform.h",
which itself is dragged in by many other headers.
Avoid that by not including these headers from "platform.h", but instead
from the source files where needed (or possibly from less popular header
files).
Currently there is no problem. However, this allows an unknowing user to
include <net/if.h> at the same time with "nm-platform.h", which is easy
to get wrong.
Note that NMSettingEthtool and NMSettingMatch don't have such
functions either.
We have API
nm_connection_get_setting (NMConnection *, GType)
nm_connection_get_setting_by_name (NMConnection *, const char *)
which can be used generically, meaning: the requested setting type
is an argument to the function. That is generally more useful and
flexible.
Don't add API which duplicates existing functionality and is (arguably)
inferiour. Drop it now. This is an ABI/API break for the current development
cycle where the 1.14.0 API is still unstable. Indeed it's already after
1.14-rc1, which is ugly. But it's also unlikely that somebody already uses
this API/ABI and is badly impacted by this change.
Note that nm_connection_get_setting() and nm_connection_get_setting_by_name()
are slightly inconvenient in C still, because they usually require a cast.
We should fix that by changing the return type to "void *". Such
a change may be possibly any time without breaking API/ABI (almost, it'd
be an API change when taking a function pointer without casting).
(cherry picked from commit a10156f516)
Note the special error codes NM_UTILS_ERROR_CONNECTION_AVAILABLE_*.
This will be used to determine, whether the profile is fundamentally
incompatible with the device, or whether just some other properties
mismatch. That information will be importand during a plain `nmcli
connection up`, where NetworkManager searches all devices for a device
to activate. If no device is found (and multiple errors happened),
we want to show the error that is most likely relevant for the user.
Also note, how NMDevice's check_connection_compatible() uses the new
class field "device_class->connection_type_check_compatible" to simplify
checks for compatible profiles.
The error reason is still unused.
It seems to me the NM_DEVICE_CLASS_DECLARE_TYPES() macro confuses more
than helping. Let's explicitly initialize the two fields, albeit with
another helper macro NM_DEVICE_DEFINE_LINK_TYPES() to get the list of
link-types right.
For consistency, also leave nop-lines like
device_class->connection_type_supported = NULL;
device_class->link_types = NM_DEVICE_DEFINE_LINK_TYPES ();
because all NMDevice class init methods should have this same
boiler plate code and to make it explicit that this is intended.
And there are only 3 occurences where this actually comes into play.
