https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1112

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1417

When you call

  nm_uuid_generate_from_strings_strv(uuid_type, type_arg, v1, v2);

you'd probably expect that both values are honored in some way.
However, if v1 happened to be NULL, then previously v2 would be ignored.

Extend nm_uuid_generate_from_strings() to accept also NULL values and
pass on the length. Currently, there are no users of nm_uuid_generate_from_strings(),
so nobody is affected by this change.

Also extend nm_uuid_generate_from_strings_strv() to take a length
argument. It still accepts "-1" to take the input strv as a NULL
terminated array.

If a positive length is provided to nm_uuid_generate_from_strings_strv(),
it hashes the same UUID as the respective NULL terminated array. But of
course only, if there is no NULL inside the array. If there are any
NULLs, a distinct UUID gets generated.

For a long time we have a function like nm_uuid_generate_from_strings().
This was recently reworked and renamed, but it preserved behavior. Preserving
behavior is important for this function, because for the existing users,
we need to keep generating the same UUIDs.

Originally, this function was a variadic function with NULL sentinel.
That means, when you write

  nm_uuid_generate_from_strings(uuid_type, type_arg, v1, v2, v3, NULL);

and v2 happens to be NULL, then v3 is ignored. That is most likely not
what the user intended. Maybe they had a bug and v2 should not be NULL.
But nm_uuid_generate_from_strings() should not require that all
arguments are non-NULL and it should not ignore arguments after the
first NULL.

For example, one user works around this via

    uuid = nm_uuid_generate_from_strings_old("ibft",
                                             s_hwaddr,
                                             s_vlanid ? "V" : "v",
                                             s_vlanid ? s_vlanid : "",
                                             s_ipaddr ? "A" : "DHCP",
                                             s_ipaddr ? s_ipaddr : "");

which is cumbersome and ugly.

That will be fixed next, by adding a function that doesn't suffer
from this problem. But "this problem" is part of the API of the
function, we cannot just change it. Instead, rename it and all
users, so they can keep doing the same.

New users of course should no longer use the "old" function.

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1369

The file "nm-meta-setting-base-impl.c" is shared by "libnm-core-impl" and
"libnmc-setting". For "libnm-core-impl" it uses a efficient lookup from the
gtype. For "libnmc-setting", that class information is not available, so
it did a linear search. Instead, do a binary search.

Tested:

    diff --git a/src/libnm-core-impl/nm-meta-setting-base-impl.c b/src/libnm-core-impl/nm-meta-setting-base-impl.c
    index 3434c858391f..62c366d2ca42 100644
    --- a/src/libnm-core-impl/nm-meta-setting-base-impl.c
    +++ b/src/libnm-core-impl/nm-meta-setting-base-impl.c
    @@ -821,6 +821,11 @@ nm_meta_setting_infos_by_gtype(GType gtype)
     {
         const NMMetaSettingInfo *setting_info;

    +#if _NM_META_SETTING_BASE_IMPL_LIBNM
    +    return _infos_by_gtype_binary_search(gtype);
    +#endif
    +    nm_assert_not_reached();
    +
     #if _NM_META_SETTING_BASE_IMPL_LIBNM
         setting_info = _infos_by_gtype_from_class(gtype);
     #else
    diff --git a/src/libnm-core-impl/tests/test-setting.c b/src/libnm-core-impl/tests/test-setting.c
    index 85d549eb766c..65fcafd076c9 100644
    --- a/src/libnm-core-impl/tests/test-setting.c
    +++ b/src/libnm-core-impl/tests/test-setting.c
    @@ -5134,6 +5134,29 @@ main(int argc, char **argv)
     {
         nmtst_init(&argc, &argv, TRUE);

    +    {
    +        gs_unref_object NMConnection *con = NULL;
    +        guint8                        ctr = 0;
    +        guint                         i;
    +
    +        con = nmtst_create_minimal_connection("test", NULL, NM_SETTING_WIRED_SETTING_NAME, NULL);
    +
    +        nm_connection_add_setting(con, nm_setting_wired_new());
    +
    +        nmtst_connection_normalize(con);
    +        nmtst_assert_connection_verifies_without_normalization(con);
    +
    +        for (i = 0; i < 10000000; i++) {
    +            ctr += GPOINTER_TO_UINT(nm_connection_get_setting(con, NM_TYPE_SETTING_WIRED));
    +            ctr += GPOINTER_TO_UINT(nm_connection_get_setting(con, NM_TYPE_SETTING_CONNECTION));
    +            ctr += GPOINTER_TO_UINT(nm_connection_get_setting(con, NM_TYPE_SETTING_PROXY));
    +            ctr += GPOINTER_TO_UINT(nm_connection_get_setting(con, NM_TYPE_SETTING_WIREGUARD));
    +            ctr += GPOINTER_TO_UINT(nm_connection_get_setting(con, NM_TYPE_SETTING_IP4_CONFIG));
    +        }
    +
    +        return !!ctr;
    +    }
    +
         g_test_add_func("/libnm/test_connection_uuid", test_connection_uuid);

         g_test_add_func("/libnm/settings/test_nm_meta_setting_types_by_priority",

Results of `make src/libnm-core-impl/tests/test-setting && libtool --mode=execute perf stat -r 5 -B src/libnm-core-impl/tests/test-setting`:

 1) previous linear search: 3,182.81 msec
 2) bsearch not inlined:    1,611.19 msec
 3) bsearch open-coded:     1,214.45 msec
 4) bsearch inlined:        1,167.70 msec
 5) lookup from class:      1,147.64 msec

 1) previous implementation
 2) using nm_array_find_bsearch()
 3) manually implementing binary search
 4) using nm_array_find_bsearch_inline()
 5) only available to libnm-core as it uses internal meta data

Note that for "libnm-core-impl" the implementation was already fast (5), and
it didn't change. It only changed to binary search for "libnmc-setting",
which arguably is a less strong use-case.

The file "nm-meta-setting-base-impl.c" is present twice in our source
tree and compiled twice. Once with internal headers of libnm-core and
once with only public headers.

Consequently, there are two implementations for
nm_meta_setting_infos_by_gtype(), one that can benefit from internal
access to the data structure, and the one for libnmc, which cannot.

Refactor the implementations, in the hope to have it clearer.