Note that most implementations use g_object_set(), and it's not
easy to detect modification. In those cases, we assume that modification
happened -- just like also the GObject setter will emit a notification
(as none of our properties use G_PARAM_EXPLICIT_NOTIFY).
These functions tend to have many arguments. They are also quite som
boilerplate to implement the hundereds of properties we have, while
we want that properties have common behaviors and similarities.
Instead of repeatedly spelling out the function arguments, use a macro.
Advantages:
- the usage of a _NM_SETT_INFO_PROP_*_FCN_ARGS macro signals that this
is an implementation of a property. You can now grep for these macros
to find all implementation. That was previously rather imprecise, you
could only `git grep '\.to_dbus_fcn'` to find the uses, but not the
implementations.
As the goal is to keep properties "similar", there is a desire to
reduce the number of similar implementations and to find them.
- changing the arguments now no longer will require you to go through
all implementations. At least not, if you merely add an argument that
has a reasonable default behavior and does not require explicit
handling by most implementation.
- it's convenient to be able to patch the argument list to let the
compiler help to reason about something. For example, the
"connection_dict" argument to from_dbus_fcn() is usually unused.
If you'd like to find who uses it, rename the parameter, and
review the (few) compiler errors.
- it does save 573 LOC of boilerplate with no actual logic or useful
information. I argue, that this simplifies the code and review, by
increasing the relative amount of actually meaningful code.
Disadvantages:
- the user no longer directly sees the argument list. They would need
cscope/ctags or an IDE to jump to the macro definition and conveniently
see all arguments.
Also use _nm_nil, so that clang-format interprets this as a function
parameter list. Otherwise, it formats the function differently.
Naming is important, because the name of a thing should give you a good
idea what it does. Also, to find a thing, it needs a good name in the
first place. But naming is also hard.
Historically, some strv helper API was named as nm_utils_strv_*(),
and some API had a leading underscore (as it is internal API).
This was all inconsistent. Do some renaming and try to unify things.
We get rid of the leading underscore if this is just a regular
(internal) helper. But not for example from _nm_strv_find_first(),
because that is the implementation of nm_strv_find_first().
- _nm_utils_strv_cleanup() -> nm_strv_cleanup()
- _nm_utils_strv_cleanup_const() -> nm_strv_cleanup_const()
- _nm_utils_strv_cmp_n() -> _nm_strv_cmp_n()
- _nm_utils_strv_dup() -> _nm_strv_dup()
- _nm_utils_strv_dup_packed() -> _nm_strv_dup_packed()
- _nm_utils_strv_find_first() -> _nm_strv_find_first()
- _nm_utils_strv_sort() -> _nm_strv_sort()
- _nm_utils_strv_to_ptrarray() -> nm_strv_to_ptrarray()
- _nm_utils_strv_to_slist() -> nm_strv_to_gslist()
- nm_utils_strv_cmp_n() -> nm_strv_cmp_n()
- nm_utils_strv_dup() -> nm_strv_dup()
- nm_utils_strv_dup_packed() -> nm_strv_dup_packed()
- nm_utils_strv_dup_shallow_maybe_a() -> nm_strv_dup_shallow_maybe_a()
- nm_utils_strv_equal() -> nm_strv_equal()
- nm_utils_strv_find_binary_search() -> nm_strv_find_binary_search()
- nm_utils_strv_find_first() -> nm_strv_find_first()
- nm_utils_strv_make_deep_copied() -> nm_strv_make_deep_copied()
- nm_utils_strv_make_deep_copied_n() -> nm_strv_make_deep_copied_n()
- nm_utils_strv_make_deep_copied_nonnull() -> nm_strv_make_deep_copied_nonnull()
- nm_utils_strv_sort() -> nm_strv_sort()
Note that no names are swapped and none of the new names existed
previously. That means, all the new names are really new, which
simplifies to find errors due to this larger refactoring. E.g. if
you backport a patch from after this change to an old branch, you'll
get a compiler error and notice that something is missing.
This is a normalization employed by NMSettingIPConfig.gateway.
Also rework NMSettingIPConfig.set_property() to no longer assert against
valid input. We want to pass there untrusted strings from D-Bus,
asserting is a horrible idea. Instead, either normalize the string or
keep the invalid text that will be rejected by verify().
A MAC address is a relatively common "type". The GObject property is of type string,
but the D-Bus type is a bytestring ("ay"). We will need a special NMSettInfoPropertType.
Note that like most implementations, the from-dbus implementation still is based
on GObject setters. This will change in the future.
Also note that the previous compare function was
_nm_setting_property_compare_fcn_default(). That is, it used to convert
the property to GVariant and compare those. The conversion to GVariant
in that case normalizes the string (e.g. it is case insensitive). Also,
only properties could be compared which were also convertible to D-Bus
(which is probably fine, because there is no guarantee the profiles that
don't verify can be compared).
The code now uses the direct comparison of the strings. That mostly
preserves the case-insensitivity of the previous comparison, because
the property setters for mac addresses all use
_nm_utils_hwaddr_canonical_or_invalid() to normalize the strings.
This is subtle, but still correct. Note that this will improve later,
by ensuring that the property setters for mac addresses automatically
perform the right normalization.
When looking at a property, it should always be clear how it is handled.
Also the "default" action should be an explicit hook.
Add _nm_setting_property_from_dbus_fcn_gprop() and set that as
from_dbus_fcn() callback to handle the "default" case which us
build around g_object_set_property().
While this adds lines of code, I think it makes the code easier to
understand. Basically, to convert a GVariant to a property, now all
properties call their from_dbus_fcn() handler, there is no special casing.
And the gprop-hook is only called for properties that are using
_nm_setting_property_from_dbus_fcn_gprop(). So, you can reason about
these two functions at separate layers.
The goal is to get rid of gprop_to_dbus_fcn() uses.
Note that there is a change in behavior. The "dns" GPtrArray in
NMSettingIPConfig is never NULL (the default of the boxed property),
thus the previous code always serialized the property, even the
empty list.
Now, empty dns properties are omitted from D-Bus.
Also, there is another change in behavior: nm_utils_ip4_dns_to_variant()
will now skip over strings that are not valid IPv4 addresses.
Previously, it would have added 0.0.0.0 (or some undefined address).
The goal is to get rid of gprop_to_dbus_fcn() uses.
Note that there is a change in behavior. The "dns" GPtrArray in
NMSettingIPConfig is never NULL (the default of the boxed property),
thus the previous code always serialized the property, even the
empty list.
Now, empty dns properties are omitted from D-Bus.
So far, we only have NMSettingClass.compare_property() hook.
The ugliness is that this hook is per-setting, when basically
all implementations only compare one property.
It feels cleaner to have a per-property hook and call that consistently.
In step one, we give all properties (the same) compare_fcn() implementation,
which delegates to the existing NMSettingClass.compare_property().
In a second step, this will be untangled.
There is one problem with this approach: NMSettInfoPropertType grows by
one pointer size, and we have potentially many such types. That should
be addressed by unifying types in the future.
Various NMSetting API would accept a property_idx parameter. Together
with the NMSettInfoSetting instance, this was useful to find the actual
NMSettInfoProperty instance.
The idea was, to provide the most of the functionality. That is, if you
might need the property_idx too, you had it -- after all, the
property_info you could lookup yourself.
However,
- literally zero users care about the property_idx. The care about
the property_info.
- if the user really, really required the property_idx, then it
is a given that it can be easily computed by
(property_info - sett_info->property_infos)
The advantage is that we use similar macros for initializing the
static structs like
const NMSettInfoPropertType nm_sett_info_propert_type_cloned_mac_address;
and the ad-hoc locations that use NM_SETT_INFO_PROPERT_TYPE().
The former exist for property types that are used more than once.
The latter exist for convenience, where a property type is implemented
at only one place.
Also, there are few direct references to _nm_setting_property_to_dbus_fcn_gprop().
all users use NM_SETT_INFO_PROPERT_TYPE_GPROP() or
NM_SETT_INFO_PROPERT_TYPE_GPROP_INIT().
If a property can be converted to D-Bus, then always set the
to_dbus_fcn() handler. The only caller of to_dbus_fcn() is
property_to_dbus(), so this means that property_to_dbus()
has no more default implementation and always delegates to
to_dbus_fcn().
The code is easier to understand if all properties implement
to_dbus_fcn() the same way.
Also, there is supposed to be a split between NMSettInfoProperty (info about
the property) and NMSettInfoPropertType (the type). The idea is that
each property (obviously) requires its distinct NMSettInfoProperty, but
they can share a common type implementation.
With NMSettInfoPropertType.gprop_to_dbus_fcn that is often violated because
many properties that implement NMSettInfoPropertType.gprop_to_dbus_fcn
require a special type implementation. As such, gprop_to_dbus_fcn should
be part of the property info and not the property type. The first step towards
that is unifying all properties to use to_dbus_fcn().
However, don't also use the NM_DEPRECATED_IN_1_32 macro, because that
causes annoying compiler warnings.
There is no replacement for the function in libnm, nor is it planned
to add one. So users may still call it, but they are now warned by
documentation that it may not be a good idea.
Found by Coverity:
Error: RESOURCE_LEAK (CWE-772):
NetworkManager-1.31.3/src/libnm-core-impl/nm-utils.c:2772: alloc_fn: Storage is returned from allocation function "nm_utils_tc_action_from_str".
NetworkManager-1.31.3/src/libnm-core-impl/nm-utils.c:2772: var_assign: Assigning: "action" = storage returned from "nm_utils_tc_action_from_str(extra_opts, error)".
NetworkManager-1.31.3/src/libnm-core-impl/nm-utils.c:2785: leaked_storage: Variable "action" going out of scope leaks the storage it points to.
# 2783| tfilter = nm_tc_tfilter_new(kind, parent, error);
# 2784| if (!tfilter)
# 2785|-> return NULL;
# 2786|
# 2787| nm_tc_tfilter_set_handle(tfilter, handle);
Fixes: de41c45e61 ('libnm-core: add functionality for dealing with tc-style traffic filter specifiers')
We use util-linux's libuuid for handling UUIDs. But UUIDs are
really a trivial thing, at least the portion that we use.
Reimplement the parse/unparse/generate_random() methods and drop
the dependency. Note that no other libraries from our dependency chain
was dragging in libuuid, so thereby we really get rid of the dependency.
We still require libuuid for building, because it is used by an example
program. Maybe that should be changed, to avoid the build dependency.
But that can be done at a later time.
nm-settings-connection.c has code similar to this in two places:
/* FIXME: improve NMConnection API so we can avoid the overhead of cloning the connection,
* in particular if there are no secrets to begin with. */
connection_cloned = nm_simple_connection_new_clone(new);
/* Clear out unwanted secrets */
_nm_connection_clear_secrets_by_secret_flags(connection_cloned,
NM_SETTING_SECRET_FLAG_NOT_SAVED
| NM_SETTING_SECRET_FLAG_AGENT_OWNED);
secrets = nm_g_variant_ref_sink(
nm_connection_to_dbus(connection_cloned, NM_CONNECTION_SERIALIZE_ONLY_SECRETS));
It seems the secrets filtering can be done by nm_connection_to_dbus() if
the NM_CONNECTION_SERIALIZE_* flags are extended. The current set of
flags contains flags that start with NO, ONLY and WITH prefixes, which
makes it useless for combining the flags because most combinations of
more than one flag don't have a clear interpretation. So they're mostly
useful when used alone, i.e. you'd need to add a new enum value for
each new subset of settings to be serialized.
To get the most flexibility from a small set of flags they should
either all be of the WITH_* type or NO_* type. In the former case they
could be combined to extend the subset of properties serialized, in the
latter case each flag would reduce the subset. After trying both
options I found it's easier to adapt the current set of flags to the
WITH_* schema while keeping binary and source compatibility. This
commit changes the set of flags in the following way:
NM_CONNECTION_SERIALIZE_ALL is kept for compatibility but is equivalent
to a combination of other flags.
NM_CONNECTION_SERIALIZE_WITH_NON_SECRET is added with the same value as
NM_CONNECTION_SERIALIZE_NO_SECRETS, it implies that non-secret
properties are included but doesn't prevent including other properties.
Since it couldn't be meaningfully combined with any other flag this
change shouldn't break compatibility.
Similarly NM_CONNECTION_SERIALIZE_WITH_SECRETS is added with the same
value as existing NM_CONNECTION_SERIALIZE_ONLY_SECRETS with the same
consideration about compatibility.
NM_CONNECTION_SERIALIZE_WITH_SECRETS_AGENT_OWNED and the new
NM_CONNECTION_SERIALIZE_WITH_SECRETS_SYSTEM_OWNED and
NM_CONNECTION_SERIALIZE_WITH_SECRETS_NOT_SAVED add only subsets of
secrets and can be combined. For backwards compatibility
NM_CONNECTION_SERIALIZE_ONLY_SECRETS is basically ignored when either of
these three is present, so that the value:
..ONLY_SECRETS | ..AGENT_OWNED works as previously.
nm_utils_ptrarray_find_binary_search() had two additional output
arguments: the first and last index -- in case the sorted list contains
duplicates.
That's nice, and was used in the past. But now, those output arguments
are no longer used.
So drop them from nm_utils_ptrarray_find_binary_search().
Actually, we could now also drop the previous variant
nm_utils_ptrarray_find_binary_search_range(), as it's only used by unit
tests. However, although not rocket science, getting this right is not
entirely trivial, so lets keep the code in case we need it again.
"libnm-core/" is rather complicated. It provides a static library that
is linked into libnm.so and NetworkManager. It also contains public
headers (like "nm-setting.h") which are part of public libnm API.
Then we have helper libraries ("libnm-core/nm-libnm-core-*/") which
only rely on public API of libnm-core, but are themself static
libraries that can be used by anybody who uses libnm-core. And
"libnm-core/nm-libnm-core-intern" is used by libnm-core itself.
Move "libnm-core/" to "src/". But also split it in different
directories so that they have a clearer purpose.
The goal is to have a flat directory hierarchy. The "src/libnm-core*/"
directories correspond to the different modules (static libraries and set
of headers that we have). We have different kinds of such modules because
of how we combine various code together. The directory layout now reflects
this.
