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No longer use GDBusObjectMangaerClient and gdbus-codegen generated classes for the NMClient cache. Instead, use GDBusConnection directly and a custom implementation (NMLDBusObject) for caching D-Bus' ObjectManager data. CHANGES ------- - This is a complete rework. I think the previous implementation was difficult to understand. There were unfixed bugs and nobody understood the code well enough to fix them. Maybe somebody out there understood the code, but I certainly did not. At least nobody provided patches to fix those issues. I do believe that this implementation is more straightforward and easier to understand. It removes a lot of layers of code. Whether this claim of simplicity is true, each reader must decide for himself/herself. Note that it is still fairly complex. - There was a lingering performance issue with large number of D-Bus objects. The patch tries hard that the implementation scales well. Of course, when we cache N objects that have N-to-M references to other, we still are fundamentally O(N*M) for runtime and memory consumption (with M being the number of references between objects). But each part should behave efficiently and well. - Play well with GMainContext. libnm code (NMClient) is generally not thread safe. However, it should work to use multiple instances in parallel, as long as each access to a NMClient is through the caller's GMainContext. This follows glib's style and effectively allows to use NMClient in a multi threaded scenario. This implies to stick to a main context upon construction and ensure that callbacks are only invoked when iterating that context. Also, NMClient itself shall never iterate the caller's context. This also means, libnm must never use g_idle_add() or g_timeout_add(), as those enqueue sources in the g_main_context_default() context. - Get ordering of messages right. All events are consistently enqueued in a GMainContext and processed strictly in order. For example, previously "nm-object.c" tried to combine signals and emit them on an idle handler. That is wrong, signals must be emitted in the right order and when they happen. Note that when using GInitable's synchronous initialization to initialize the NMClient instance, NMClient internally still operates fully asynchronously. In that case NMClient has an internal main context. - NMClient takes over most of the functionality. When using D-Bus' ObjectManager interface, one needs to handle basically the entire state of the D-Bus interface. That cannot be separated well into distinct parts, and even if you try, you just end up having closely related code in different source files. Spreading related code does not make it easier to understand, on the contrary. That means, NMClient is inherently complex as it contains most of the logic. I think that is not avoidable, but it's not as bad as it sounds. - NMClient processes D-Bus messages and state changes in separate steps. First NMClient unpacks the message (e.g. _dbus_handle_properties_changed()) and keeps track of the changed data. Then we update the GObject instances (_dbus_handle_obj_changed_dbus()) without emitting any signals yet. Finally, we emit all signals and notifications that were collected (_dbus_handle_changes_commit()). Note that for example during the initial GetManagedObjects() reply, NMClient receive a large amount of state at once. But we first apply all the changes to our GObject instances before emitting any signals. The result is that signals are always emitted in a moment when the cache is consistent. The unavoidable downside is that when you receive a property changed signal, possibly many other properties changed already and more signals are about to be emitted. - NMDeviceWifi no longer modifies the content of the cache from client side during poke_wireless_devices_with_rf_status(). The content of the cache should be determined by D-Bus alone and follow what NetworkManager service exposes. Local modifications should be avoided. - This aims to bring no API/ABI change, though it does of course bring various subtle changes in behavior. Those should be all for the better, but the goal is not to break any existing clients. This does change internal (albeit externally visible) API, like dropping NM_OBJECT_DBUS_OBJECT_MANAGER property and NMObject no longer implementing GInitableIface and GAsyncInitableIface. - Some uses of gdbus-codegen classes remain in NMVpnPluginOld, NMVpnServicePlugin and NMSecretAgentOld. These are independent of NMClient/NMObject and should be reworked separately. - While we no longer use generated classes from gdbus-codegen, we don't need more glue code than before. Also before we constructed NMPropertiesInfo and a had large amount of code to propagate properties from NMDBus* to NMObject. That got completely reworked, but did not fundamentally change. You still need about the same effort to create the NMLDBusMetaIface. Not using generated bindings did not make anything worse (which tells about the usefulness of generated code, at least in the way it was used). - NMLDBusMetaIface and other meta data is static and immutable. This avoids copying them around. Also, macros like NML_DBUS_META_PROPERTY_INIT_U() have compile time checks to ensure the property types matches. It's pretty hard to misuse them because it won't compile. - The meta data now explicitly encodes the expected D-Bus types and makes sure never to accept wrong data. That would only matter when the server (accidentally or intentionally) exposes unexpected types on D-Bus. I don't think that was previously ensured in all cases. For example, demarshal_generic() only cared about the GObject property type, it didn't know the expected D-Bus type. - Previously GDBusObjectManager would sometimes emit warnings (g_log()). Those probably indicated real bugs. In any case, it prevented us from running CI with G_DEBUG=fatal-warnings, because there would be just too many unrelated crashes. Now we log debug messages that can be enabled with "LIBNM_CLIENT_DEBUG=trace". Some of these messages can also be turned into g_warning()/g_critical() by setting LIBNM_CLIENT_DEBUG=warning,error. Together with G_DEBUG=fatal-warnings, this turns them into assertions. Note that such "assertion failures" might also happen because of a server bug (or change). Thus these are not common assertions that indicate a bug in libnm and are thus not armed unless explicitly requested. In our CI we should now always run with LIBNM_CLIENT_DEBUG=warning,error and G_DEBUG=fatal-warnings and to catch bugs. Note that currently NetworkManager has bugs in this regard, so enabling this will result in assertion failures. That should be fixed first. - Note that this changes the order in which we emit "notify:devices" and "device-added" signals. I think it makes the most sense to emit first "device-removed", then "notify:devices", and finally "device-added" signals. This changes behavior for commit |
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| data | ||
| dispatcher | ||
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| examples | ||
| introspection | ||
| libnm | ||
| libnm-core | ||
| m4 | ||
| man | ||
| po | ||
| shared | ||
| src | ||
| tools | ||
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| .dir-locals.el | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .mailmap | ||
| .travis.yml | ||
| AUTHORS | ||
| autogen.sh | ||
| ChangeLog | ||
| config-extra.h.meson | ||
| config-extra.h.mk | ||
| config.h.meson | ||
| configure.ac | ||
| CONTRIBUTING | ||
| COPYING | ||
| COPYING.GFDL | ||
| COPYING.LGPL | ||
| linker-script-binary.ver | ||
| linker-script-devices.ver | ||
| linker-script-settings.ver | ||
| MAINTAINERS | ||
| Makefile.am | ||
| Makefile.examples | ||
| Makefile.glib | ||
| Makefile.vapigen | ||
| meson.build | ||
| meson_options.txt | ||
| NetworkManager.pc.in | ||
| NEWS | ||
| README | ||
| TODO | ||
| valgrind.suppressions | ||
****************** 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.