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Thomas Haller bd8d49495b
libnm: embed private structure in NMSetting and avoid g_type_class_add_private()
Historically, the NMSetting types were in public headers. Theoretically,
that allowed users to subtype our classes. However in practice that was
impossible because they lacked required access to internal functions to
fully create an NMSetting class outside of libnm. And it also was not
useful, because you simply cannot extend libnm by subtyping a libnm
class. And supporting such a use case would be hard and limit what we can
do in libnm.

Having GObject structs in public headers also require that we don't
change it's layout. The ABI of those structs must not change, if anybody
out there was actually subclassing our GObjects.

In libnm 1.34 (commit e46d484fae ('libnm: hide NMSetting types from
public headers')) we moved the structs from headers to internal.
This would have caused a compiler error if anybody was using those
struct definitions. However, we still didn't change the ABI/layout so
that we didn't break users who relied on it (for whatever reason).

It doesn't seem there were any affected user. We waited long enough.
Change internal ABI.

No longer use g_type_class_add_private(). Instead, embed the private
structs directly (_NM_GET_PRIVATE()) or indirectly
(_NM_GET_PRIVATE_PTR()) in the object.

The main benefit is for debugging in the debugger, where we can now
easily find the private data. Previously that was so cumbersome to be
effectively impossible.

It's also the fastest possible way, since NM_SETTING_*_GET_PRIVATE()
literally resolves to "&self->_priv" (plus static asserts and
nm_assert() for type checking).

_NM_GET_PRIVATE() also propagates constness and requires that the
argument is a compatible pointer type (at compile time).

Note that g_type_class_add_private() is also deprecated in glib 2.58 and
replaced by G_ADD_PRIVATE(). For one, we still don't rely on 2.58. Also,
G_ADD_PRIVATE() is a worse solution as it supports a usecase that we
don't care for (public structs in headers). _NM_GET_PRIVATE() is still
faster, works with older glib and most importantly: is better for
debugging as you can find the private data from an object pointer.

For NMSettingIPConfig this is rather awkward, because all direct
properties require a common "klass->private_offset". This was however
the case before this change. Nothing new here. And if you ever touch
this and do something wrong, many unit tests will fail. It's almost
impossible to get wrong, albeit it can be confusing to understand.

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1773
2023-10-31 11:29:37 +01:00
.gitlab gitlab: improve issue and merge-request templates 2023-06-27 09:51:46 +02:00
.gitlab-ci gitlab-ci: fix detection and handling of Ubuntu 18.04 2023-06-30 18:51:13 +02:00
contrib spec: Add missing epoch to some obsoleted versions 2023-10-25 10:20:03 +00:00
data doc: update Documentation reference in NetworkManager-wait-online.service 2023-06-07 16:48:30 +02:00
docs build: add missing source dirs to meson doc build 2023-10-25 10:13:53 +00:00
examples examples: support older libnm without NM.SettingOvsOtherConfig in "ovs-external-ids.py" 2023-02-16 10:17:48 +01:00
introspection wifi: parse access point announced bandwidth 2023-08-02 00:54:27 +02:00
m4 docs,m4: remove paragraph about writing to FSF 2023-10-06 13:27:59 +02:00
man man: improve NM-dispatcher man page 2023-10-06 13:27:59 +02:00
po Update Russian translation 2023-09-25 14:21:25 +02:00
src libnm: embed private structure in NMSetting and avoid g_type_class_add_private() 2023-10-31 11:29:37 +01:00
tools man nm-setting-*: proper format for gtkdoc constants 2023-09-21 15:57:35 +02:00
vapi all: add "link" setting 2023-03-02 16:51:16 +01:00
.clang-format glib-aux/prioq: rename NM_PRIOQ_FOREACH_ITEM() to nm_prioq_for_each() 2023-03-21 15:58:39 +01:00
.dir-locals.el misc: add toplevel .dir-locals file that tells Emacs to show trailing whitespace 2013-03-08 15:15:28 +01:00
.git-blame-ignore-revs clang-format: add reformatting commit to ".git-blame-ignore-revs" 2023-05-19 12:49:22 +02:00
.gitignore gitignore: ignore nm-settings-docs-gir-*.xml 2023-10-18 08:04:44 +02:00
.gitlab-ci.yml contrib: add libpsl-dev to debian requirements 2023-09-13 16:29:01 +02:00
.mailmap mailmap: update Jordi's identity 2023-06-28 13:50:25 +02:00
.triage-policies.yml triage: only make stale issues/merge-requests with a label instead of autoclosing them 2023-05-08 11:04:50 +02:00
AUTHORS docs: fix typo in docs for upstream mailing list 2022-11-07 17:50:29 +01:00
autogen.sh build: stop relying on intltool for i18n 2022-06-27 13:40:09 +02:00
ChangeLog Changelog: update references to "main" branch 2021-04-01 22:30:20 +02:00
config-extra.h.meson build: remove duplicate and unused RUNDIR define 2019-05-17 21:24:18 +02:00
config-extra.h.mk build: regenerate config-extra.h if configure was re-run with different arguments 2019-09-25 15:55:37 +02:00
config.h.meson build,core: add a "main.migrate-ifcfg-rh" configuration option 2023-07-25 15:39:06 +02:00
configure.ac release: bump version to 1.45.5 (development) 2023-10-18 11:06:37 +02:00
CONTRIBUTING.md CONTRIBUTING: don't use signed-off-by in NetworkManager 2023-06-07 14:25:05 +02:00
COPYING COPYING: make sure we ship the relevant license texts 2019-09-10 11:10:52 +02:00
COPYING.GFDL COPYING: make sure we ship the relevant license texts 2019-09-10 11:10:52 +02:00
COPYING.LGPL COPYING: make sure we ship the relevant license texts 2019-09-10 11:10:52 +02:00
linker-script-binary.ver iface-helper/build: add linker version script 2016-10-13 21:33:33 +02:00
linker-script-devices.ver devices/build: use one linker-script-devices.ver for all device plugins 2016-10-13 21:36:06 +02:00
linker-script-settings.ver settings/build: add linker version script for settings plugins 2016-10-13 21:33:33 +02:00
lsan.suppressions tests/sanitizer: suppress leak in openssl 2020-05-14 12:03:24 +02:00
MAINTAINERS misc: update maintainers and authors 2016-04-21 13:39:03 -05:00
MAINTAINERS.md MAINTAINERS: how to merge merge requests 2023-06-07 14:25:05 +02:00
Makefile.am nmcli: don't warn version mismatch with daemon not running 2023-10-18 08:13:22 +02:00
Makefile.examples examples: add python example for reapply 2022-12-14 17:31:17 +01:00
Makefile.glib all: drop emacs file variables from source files 2019-06-11 10:04:00 +02:00
Makefile.vapigen build: fix make always re-making vapigen target 2016-10-21 18:46:03 +02:00
meson.build release: bump version to 1.45.5 (development) 2023-10-18 11:06:37 +02:00
meson_options.txt build,core: add a "main.migrate-ifcfg-rh" configuration option 2023-07-25 15:39:06 +02:00
NEWS libnm: embed private structure in NMSetting and avoid g_type_class_add_private() 2023-10-31 11:29:37 +01:00
README.md doc: rename "README" to "README.md" 2022-03-21 17:19:47 +01:00
RELICENSE.md docs: fix typo in docs for upstream mailing list 2022-11-07 17:50:29 +01:00
TODO core/trivial: rename NM_SHUTDOWN_TIMEOUT_MS to NM_SHUTDOWN_TIMEOUT_MAX_MSEC 2022-02-24 09:38:52 +01:00
valgrind.suppressions all: goodbye libnm-glib 2019-04-16 15:52:27 +02:00


NetworkManager core daemon has moved to gitlab.freedesktop.org!

git clone https://gitlab.freedesktop.org/NetworkManager/NetworkManager.git


Networking that Just Works

NetworkManager attempts to keep an active network connection available at all times. The point of NetworkManager is to make networking configuration and setup as painless and automatic as possible. NetworkManager is intended to replace default route, replace other routes, set IP addresses, and in general configure networking as NM sees fit (with the possibility of manual override as necessary). In effect, the goal of NetworkManager is to make networking Just Work with a minimum of user hassle, but still allow customization and a high level of manual network control. If you have special needs, we'd like to hear about them, but understand that NetworkManager is not intended for every use-case.

NetworkManager will attempt to keep every network device in the system up and active, as long as the device is available for use (has a cable plugged in, the killswitch isn't turned on, etc). Network connections can be set to 'autoconnect', meaning that NetworkManager will make that connection active whenever it and the hardware is available.

"Settings services" store lists of user- or administrator-defined "connections", which contain all the settings and parameters required to connect to a specific network. NetworkManager will never activate a connection that is not in this list, or that the user has not directed NetworkManager to connect to.

How it works:

The NetworkManager daemon runs as a privileged service (since it must access and control hardware), but provides a D-Bus interface on the system bus to allow for fine-grained control of networking. NetworkManager does not store connections or settings, it is only the mechanism by which those connections are selected and activated.

To store pre-defined network connections, two separate services, the "system settings service" and the "user settings service" store connection information and provide these to NetworkManager, also via D-Bus. Each settings service can determine how and where it persistently stores the connection information; for example, the GNOME applet stores its configuration in GConf, and the system settings service stores its config in distro-specific formats, or in a distro- agnostic format, depending on user/administrator preference.

A variety of other system services are used by NetworkManager to provide network functionality: wpa_supplicant for wireless connections and 802.1x wired connections, pppd for PPP and mobile broadband connections, DHCP clients for dynamic IP addressing, dnsmasq for proxy nameserver and DHCP server functionality for internet connection sharing, and avahi-autoipd for IPv4 link-local addresses. Most communication with these daemons occurs, again, via D-Bus.

Why doesn't my network Just Work?

Driver problems are the #1 cause of why NetworkManager sometimes fails to connect to wireless networks. Often, the driver simply doesn't behave in a consistent manner, or is just plain buggy. NetworkManager supports only those drivers that are shipped with the upstream Linux kernel, because only those drivers can be easily fixed and debugged. ndiswrapper, vendor binary drivers, or other out-of-tree drivers may or may not work well with NetworkManager, precisely because they have not been vetted and improved by the open-source community, and because problems in these drivers usually cannot be fixed.

Sometimes, command-line tools like 'iwconfig' will work, but NetworkManager will fail. This is again often due to buggy drivers, because these drivers simply aren't expecting the dynamic requests that NetworkManager and wpa_supplicant make. Driver bugs should be filed in the bug tracker of the distribution being run, since often distributions customize their kernel and drivers.

Sometimes, it really is NetworkManager's fault. If you think that's the case, please file a bug at:

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

Attaching NetworkManager debug logs from the journal (or wherever your distribution directs syslog's 'daemon' facility output, as /var/log/messages or /var/log/daemon.log) is often very helpful, and (if you can get) a working wpa_supplicant config file helps enormously. See the logging section of file contrib/fedora/rpm/NetworkManager.conf for how to enable debug logging in NetworkManager.