"nm-value-type.h" is a header-only file, as it contains only small
accessors that should be inlined.
As such, the implementation of these functions is guarded by "#ifdef
NM_VALUE_TYPE_DEFINE_FUNCTIONS", so that one can use this header (and
NMValueType enum) with less overhead (at compile time).
Glib has GValue which used for boxing value.
Add NMValueType enum, which has a similar purpose, but it's much more
limited.
- contrary to GValue, the type must be tracked separately from the
user-data. That is, the "user-data" is only a pointer of appropriate
type, and the knowledge of the actual NMValueType is kept separately.
This will be used to have a static list of meta-data that knows the
value types, but keeping the values independent of this type
information. With GValue this would not be possible.
- the use case is much more limited. Just support basic integers,
boolean and strings. Nothing fancy.
Note that we already do something similar at muliple places. See for
example NMVariantAttributeSpec and nm_utils_team_link_watcher_to_string().
These could/should instead use NMValueType.
The type of the "data" pointer may not be compatible with the type of
the "to_free" / output pointer. This is due to constness, and that we
are unable in C to remove constness from a type.
For example,
{
const char *const *data = ...;
gs_free const char **cpy_to_free = NULL;
const char **cpy;
cpy = nm_memdup_maybe_a (300, data, NM_PTRARRAY_LEN (data) + 1, &cpy_to_free);
}
is prefectly valid , but would not have compiled.
It shows that "data" is not of type "*(&cpy_to_free)", but rather
it might be a non-const pointer of the same type.
Fixes: d0e1d0e626 ('shared: propagate types in nm_malloc_maybe_a(), nm_malloc0_maybe_a(), nm_memdup_maybe_a()')
We want the the hash-seed array is alined so it can be used both as
guint, guint32, and guint64 directly. Don't use _nm_alignas() but
instead just add the fields to the union so we get proper alignment.
While at at, also let the seed argument to c_siphash_init() be aligned
to 64 integers. c_siphash_init() does not require that, but it tries to
read the seed as (unaligned) LE 64 bit integers. So, it doesn't hurt.
We want to log pointer values to indicate the related parties of a
log message. But we should not, because plain pointer values can be
used to defeat ASLR.
Instead, we have nm_hash_obfuscate_ptr() to managle a pointer and give
a distinct (albeit not 100% unique) 64 bit integer for logging.
But for the logging messages to be meaning-full, all related parties
must use the same static-seed.
Add a macro NM_HASH_OBFUSCATE_PTR() that uses a particular seed.
... and nm_dbus_connection_call_get_name_owner().
We are going to use GDBusConnection more instead of GDBusProxy. Hence,
these two functions are the standard repertoire and used over and over.
Their arguments are complicated enough to warrant a small helper.
It will be used for "/var/lib/NetworkManager/seen-bssids" and
"/var/lib/NetworkManager/timestamps" which currently is implemented
in NMSettingConnection.
From the files under "shared/nm-utils" we build an internal library
that provides glib-based helper utilities.
Move the files of that basic library to a new subdirectory
"shared/nm-glib-aux" and rename the helper library "libnm-core-base.la"
to "libnm-glib-aux.la".
Reasons:
- the name "utils" is overused in our code-base. Everything's an
"utils". Give this thing a more distinct name.
- there were additional files under "shared/nm-utils", which are not
part of this internal library "libnm-utils-base.la". All the files
that are part of this library should be together in the same
directory, but files that are not, should not be there.
- the new name should better convey what this library is and what is isn't:
it's a set of utilities and helper functions that extend glib with
funcitonality that we commonly need.
There are still some files left under "shared/nm-utils". They have less
a unifying propose to be in their own directory, so I leave them there
for now. But at least they are separate from "shared/nm-glib-aux",
which has a very clear purpose.
(cherry picked from commit 80db06f768)
