Support managing the loopback interface through NM as the users want to
set the proper mtu for loopback interface when forwarding the packets.
Additionally, the IP addresses, DNS, route and routing rules are also
allowed to configure for the loopback connection profiles.
https://bugzilla.redhat.com/show_bug.cgi?id=2060905
gtk-doc gets confused by these, ignore them:
common.py:ParseFunctionDeclaration:541:WARNING:Cannot parse args for
function in "nm_device_get_hw_address) const char
*nm_device_dummy_get_hw_address(NMDeviceDummy *device
common.py:ParseFunctionDeclaration:541:WARNING:Cannot parse args for
function in "nm_device_get_ports) const GPtrArray
*nm_device_ovs_port_get_slaves(NMDeviceOvsPort *device
For some reason it's still confused if NM_AVAILABLE_* comes first.
I refuse to look into that, just reorder them.
These went out of date and now all sorts of useless junk is included in
the libnm documentation
They contain everything outside *-public/ (perhaps they could be generated,
but I'm not doing that) and nm-core-types.h (because that one confuses
gtk-doc in an outrageous manner).
Turns out automake doesn't like either that we add dependencies to a
target conditionally. Not sure why, but it's a tasteless thing to do
nevertheless:
gtk-doc.make:174: warning: $(DOC_MAIN_SGML_FILE) was already defined in condition BUILD_DOCS, which is included in condition TRUE ...
docs/api/Makefile.am:112: 'gtk-doc.make' included from here
docs/api/Makefile.am:14: ... '$(DOC_MAIN_SGML_FILE)' previously defined here
In any case, the dependency is wrong in the first place -- the source
document doesn't depend on other source. The target (which is a stamp
file, since the xslt processor produces multiple files) does! Moreover,
there's a dependency of the stamp file on $(content_files) already, so
including GENERATED_FILES (like we already do) in content_files should
be sufficient.
While at that, deal with other not-so-nice things; don't extend "all"
target needlessly and don't define a target conditionally.
NetworkManager-wait-online is a constant source of confusion,
as it seems to delay the boot (when it's often just the messenger
or either a network problem, a NetworkManager misconfiguration
or a misconfiguration of other systemd services).
Try to clear that up with a manual page.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1130
"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.
We want to use these defines for option names also in "shared/nm-base"
(and in turn in "shared/nm-platform), which cannot include "libnm-core".
However, they are also public API of libnm.
To get this done, in a first step, move these defines to a new header
"libnm-core/nm-ethtool-utils.h".
Since now the name "nm-ethtool-utils.h" is taken, also rename
nm-libnm-core-intern files.
NetworkManager is now able to configure veth interfaces throught the
NMSettingVeth. Veth interfaces only have "peer" property.
In order to support Veth interfaces in NetworkManager the design need
to pass the following requirements:
* Veth setting only has "peer" attribute.
* Ethernet profiles must be applicable to Veth interfaces.
* When creating a veth interface, the peer will be managed by
NetworkManager but will not have a profile.
* Veth connection can reapply only if the peer has not been modified.
* In order to modify the veth peer, NetworkManager must deactivate the
connection and create a new one with peer modified.
In general, it should support the basis of veth interfaces but without
breaking any existing feature or use case. The users that are using veth
interfaces as ethernet should not notice anything changed unless they
specified the veth peer setting.
Creating a Veth interface in NetworkManager is useful even without the
support for namespaces for some use cases, e.g "connecting one side of
the veth to an OVS bridge and the other side to a Linux bridge" this is
done when using OVN kubernetes [1][2]. In addition, it would provide
persistent configuration and rollback support for Veth interfaces.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1885605
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1894139
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
On Fedora 33 when compiling NetworkManager it is failing with the
following error:
```
ERROR: files left in build directory after distclean:
./docs/libnm/libnm.actions
make[1]: *** [Makefile:18427: distcleancheck] Error 1
make[1]: Leaving directory '/builddir/nm-build/NetworkManager/NetworkManager-1.27.90/_build/sub'
make: *** [Makefile:18356: distcheck] Error 1
Error make distcheck
```
Adding the file to the DISTCLEANFILES will enforce the removal of this
file.
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/659
"nm-settings-docs-nmcli.xml" will be generated by a tool that depends on
"clients/common/". The file should thus not be in libnm directory, otherwise
there is a circular dependency.
Move the file to "man/" directory.
For consistency, also move "nm-settings-docs-dbus.xml". Note that we
cannot move "nm-settings-docs-gir.xml" to "man/", because that one is
needed for building clients.
Like the previous commit. Move code that depends on libnm out
of shared to avoid circular dependency.
Also add a readme file explaining the reason for existence of
the helper library.
Like the previous commit. Move code that depends on libnm-core out
of shared to avoid circular dependency.
Also add a readme file explaining the reason for existence of
the helper libraries nm-libnm-core-intern and nm-libnm-core-aux.
The "shared" directory is used by libnm-core, it should thus only depend on
code that is in the "shared" directory. Otherwise there is a circular
dependency, and meson's subdir() does not work nicely.
Also, libnm-core is really part of (and also an extension of) libnm-core,
so it belongs there.
I guess, the original idea was that this is also an extension for libnm,
so another project could take these utility functions (by copying them
into their source tree) and use them. That is still possible, it's
just that the sources are no longer under the shared directory.
Also add a readme to explain the non-obvious meaning of these files.
Originally, these files were part of libnm-core and linked together.
However, that is a licensing violation, because the code is GPL-2.0+
licensed, while libnm-core also gets linked with libnm (it must thus
be LGPL-2.1+). The original intent behind moving the code to "shared/"
was to avoid the licensing issue, but also to prepare when we would add
a separate, GPL licensed libnm-keyfile. However, currently we hope to
be able to relicense the code, so that it actually could be exposed as
part of libnm. This is work in progress at ([1]).
[1] https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/ ## 517
Anyway, the current directory layout is problematic. libnm-keyfile
depends on libnm-core, while libnm-core depends on code under shared.
That means, there is a circular dependency and meson's subdir() does
not work well.
Move the code.
A significant part of NetworkManager's API are the connection profiles, documented
in `man nm-settings*`. But there are different aspects about profiles, depending
on what you are interested. There is the D-Bus API, nmcli options, keyfile format,
and ifcfg-rh format. Additionally, there is also libnm API.
Add distinct manual pages for the four aspects. Currently the two new manual
pages "nm-settings-dbus" and "nm-settings-nmcli" are still identical to the
former "nm-settings.5" manual. In the future, they will diverge to
account for the differences.
There are the following aspects:
- "dbus"
- "keyfile"
- "ifcfg-rh"
- "nmcli"
For "libnm" we don't generate a separate "nm-settings-libnm" manual
page. That is instead documented via gtk-doc.
Currently the keyfile and ifcfg-rh manual pages only detail settings
which differ. But later I think also these manual pages should contain
all settings that apply.
"nm-settings-docs-dbus.xml" is "nm-settings-docs-gir.xml" merged with
"nm-property-infos-dbus.xml". The name should reflect that, also because
we will get more files with this naming scheme.
"man/nm-settings%.xml" really should depend on "common.ent".
The reason is that XSL files like "man/nm-settings.xsl" include
"common.ent".
The previous code already tried to express that, but for some
reasons this dependency was not honored. Fix that.
However, that uncovers another problem with gtk-doc.make. If we do
that without the workaround for "docs/api/Makefile.am", then
$ ./autogen.sh && make V=1 SHELL='sh -x' distcheck
breaks.
The reason is not clear to me. The new dependency leads to rebuild
"man/nm-settings-keyfile.xml". But that is worse, somehow the file
"$(top_srcdir)/man/nm-settings-keyfile.xml" ends up being read-only.
Afterwards, gtk-doc.make does
setup-build.stamp:
-$(GTK_DOC_V_SETUP)if test "$(abs_srcdir)" != "$(abs_builddir)" ;
then \
files=`echo $(SETUP_FILES) $(DOC_MODULE).types`; \
if test "x$$files" != "x" ; then \
for file in $$files ; do \
destdir=`dirname $(abs_builddir)/$$file`; \
test -d "$$destdir" || mkdir -p "$$destdir"; \
test -f $(abs_srcdir)/$$file && \
cp -pf $(abs_srcdir)/$$file $(abs_builddir)/$$file || true;
\
done; \
fi; \
fi
$(AM_V_at)touch setup-build.stamp
so that the files in build dir are also read-only. Then, make distcheck
goes ahead and builds the files once again, which fails.
You are welcome to understand why this workaround is necessary. Please
then create a better fix.
Add VRF support to the daemon. When the device we are activating is a
VRF or a VRF's slave, put routes in the table specified by the VRF
connection.
Also, introduce a VRF device type in libnm.
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 52ae28f6e5 ('libnm: queue
added/removed signals and suppress uninitialized notifications'),
but I don't think that users should actually rely on the order. Still,
the new order makes the most sense to me.
- In NetworkManager, profiles can be invisible to the user by setting
"connection.permissions". Such profiles would be hidden by NMClient's
nm_client_get_connections() and their "connection-added"/"connection-removed"
signals.
Note that NMActiveConnection's nm_active_connection_get_connection()
and NMDevice's nm_device_get_available_connections() still exposes such
hidden NMRemoteConnection instances. This behavior was preserved.
NUMBERS
-------
I compared 3 versions of libnm.
[1] 962297f908, current tip of nm-1-20 branch
[2] 4fad8c7c64, current master, immediate parent of this patch
[3] this patch
All tests were done on Fedora 31, x86_64, gcc 9.2.1-1.fc31.
The libraries were build with
$ ./contrib/fedora/rpm/build_clean.sh -g -w test -W debug
Note that RPM build already stripped the library.
---
N1) File size of libnm.so.0.1.0 in bytes. There currently seems to be a issue
on Fedora 31 generating wrong ELF notes. Usually, libnm is smaller but
in these tests it had large (and bogus) ELF notes. Anyway, the point
is to show the relative sizes, so it doesn't matter).
[1] 4075552 (102.7%)
[2] 3969624 (100.0%)
[3] 3705208 ( 93.3%)
---
N2) `size /usr/lib64/libnm.so.0.1.0`:
text data bss dec hex filename
[1] 1314569 (102.0%) 69980 ( 94.8%) 10632 ( 80.4%) 1395181 (101.4%) 1549ed /usr/lib64/libnm.so.0.1.0
[2] 1288410 (100.0%) 73796 (100.0%) 13224 (100.0%) 1375430 (100.0%) 14fcc6 /usr/lib64/libnm.so.0.1.0
[3] 1229066 ( 95.4%) 65248 ( 88.4%) 13400 (101.3%) 1307714 ( 95.1%) 13f442 /usr/lib64/libnm.so.0.1.0
---
N3) Performance test with test-client.py. With checkout of [2], run
```
prepare_checkout() {
rm -rf /tmp/nm-test && \
git checkout -B test 4fad8c7c64 && \
git clean -fdx && \
./autogen.sh --prefix=/tmp/nm-test && \
make -j 5 install && \
make -j 5 check-local-clients-tests-test-client
}
prepare_test() {
NM_TEST_REGENERATE=1 NM_TEST_CLIENT_BUILDDIR="/data/src/NetworkManager" NM_TEST_CLIENT_NMCLI_PATH=/usr/bin/nmcli python3 ./clients/tests/test-client.py -v
}
do_test() {
for i in {1..10}; do
NM_TEST_CLIENT_BUILDDIR="/data/src/NetworkManager" NM_TEST_CLIENT_NMCLI_PATH=/usr/bin/nmcli python3 ./clients/tests/test-client.py -v || return -1
done
echo "done!"
}
prepare_checkout
prepare_test
time do_test
```
[1] real 2m14.497s (101.3%) user 5m26.651s (100.3%) sys 1m40.453s (101.4%)
[2] real 2m12.800s (100.0%) user 5m25.619s (100.0%) sys 1m39.065s (100.0%)
[3] real 1m54.915s ( 86.5%) user 4m18.585s ( 79.4%) sys 1m32.066s ( 92.9%)
---
N4) Performance. Run NetworkManager from build [2] and setup a large number
of profiles (551 profiles and 515 devices, mostly unrealized). This
setup is already at the edge of what NetworkManager currently can
handle. Of course, that is a different issue. Here we just check how
long plain `nmcli` takes on the system.
```
do_cleanup() {
for UUID in $(nmcli -g NAME,UUID connection show | sed -n 's/^xx-c-.*:\([^:]\+\)$/\1/p'); do
nmcli connection delete uuid "$UUID"
done
for DEVICE in $(nmcli -g DEVICE device status | grep '^xx-i-'); do
nmcli device delete "$DEVICE"
done
}
do_setup() {
do_cleanup
for i in {1..30}; do
nmcli connection add type bond autoconnect no con-name xx-c-bond-$i ifname xx-i-bond-$i ipv4.method disabled ipv6.method ignore
for j in $(seq $i 30); do
nmcli connection add type vlan autoconnect no con-name xx-c-vlan-$i-$j vlan.id $j ifname xx-i-vlan-$i-$j vlan.parent xx-i-bond-$i ipv4.method disabled ipv6.method ignore
done
done
systemctl restart NetworkManager.service
sleep 5
}
do_test() {
perf stat -r 50 -B nmcli 1>/dev/null
}
do_test
```
[1]
Performance counter stats for 'nmcli' (50 runs):
456.33 msec task-clock:u # 1.093 CPUs utilized ( +- 0.44% )
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
5,900 page-faults:u # 0.013 M/sec ( +- 0.02% )
1,408,675,453 cycles:u # 3.087 GHz ( +- 0.48% )
1,594,741,060 instructions:u # 1.13 insn per cycle ( +- 0.02% )
368,744,018 branches:u # 808.061 M/sec ( +- 0.02% )
4,566,058 branch-misses:u # 1.24% of all branches ( +- 0.76% )
0.41761 +- 0.00282 seconds time elapsed ( +- 0.68% )
[2]
Performance counter stats for 'nmcli' (50 runs):
477.99 msec task-clock:u # 1.088 CPUs utilized ( +- 0.36% )
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
5,948 page-faults:u # 0.012 M/sec ( +- 0.03% )
1,471,133,482 cycles:u # 3.078 GHz ( +- 0.36% )
1,655,275,369 instructions:u # 1.13 insn per cycle ( +- 0.02% )
382,595,152 branches:u # 800.433 M/sec ( +- 0.02% )
4,746,070 branch-misses:u # 1.24% of all branches ( +- 0.49% )
0.43923 +- 0.00242 seconds time elapsed ( +- 0.55% )
[3]
Performance counter stats for 'nmcli' (50 runs):
352.36 msec task-clock:u # 1.027 CPUs utilized ( +- 0.32% )
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
4,790 page-faults:u # 0.014 M/sec ( +- 0.26% )
1,092,341,186 cycles:u # 3.100 GHz ( +- 0.26% )
1,209,045,283 instructions:u # 1.11 insn per cycle ( +- 0.02% )
281,708,462 branches:u # 799.499 M/sec ( +- 0.01% )
3,101,031 branch-misses:u # 1.10% of all branches ( +- 0.61% )
0.34296 +- 0.00120 seconds time elapsed ( +- 0.35% )
---
N5) same setup as N4), but run `PAGER= /bin/time -v nmcli`:
[1]
Command being timed: "nmcli"
User time (seconds): 0.42
System time (seconds): 0.04
Percent of CPU this job got: 107%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.43
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 34456
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 6128
Voluntary context switches: 1298
Involuntary context switches: 1106
Swaps: 0
File system inputs: 0
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
[2]
Command being timed: "nmcli"
User time (seconds): 0.44
System time (seconds): 0.04
Percent of CPU this job got: 108%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.44
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 34452
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 6169
Voluntary context switches: 1849
Involuntary context switches: 142
Swaps: 0
File system inputs: 0
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
[3]
Command being timed: "nmcli"
User time (seconds): 0.32
System time (seconds): 0.02
Percent of CPU this job got: 102%
Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.34
Average shared text size (kbytes): 0
Average unshared data size (kbytes): 0
Average stack size (kbytes): 0
Average total size (kbytes): 0
Maximum resident set size (kbytes): 29196
Average resident set size (kbytes): 0
Major (requiring I/O) page faults: 0
Minor (reclaiming a frame) page faults: 5059
Voluntary context switches: 919
Involuntary context switches: 685
Swaps: 0
File system inputs: 0
File system outputs: 0
Socket messages sent: 0
Socket messages received: 0
Signals delivered: 0
Page size (bytes): 4096
Exit status: 0
---
N6) same setup as N4), but run `nmcli monitor` and look at `ps aux` for
the RSS size.
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
[1] me 1492900 21.0 0.2 461348 33248 pts/10 Sl+ 15:02 0:00 nmcli monitor
[2] me 1490721 5.0 0.2 461496 33548 pts/10 Sl+ 15:00 0:00 nmcli monitor
[3] me 1495801 16.5 0.1 459476 28692 pts/10 Sl+ 15:04 0:00 nmcli monitor
We don't need such data duplicated. The build setup should
have only one configuration_data() for patching such values.
Now we only have one global, immutable data_conf dictionary with
configuration values. Note that none of the users of data_conf uses all
entries, but as the entries are basically only dependent on the
meson/configure option and valid for the entire project, this simplifies
to handling.
Note that D-Bus is fundamentally asynchronous. Doing blocking calls
on top of D-Bus is odd, especially for libnm's NMClient. That is because
NMClient essentially is a client-side cache of the objects from the D-Bus
interface. This cache should be filled exclusively by (asynchronous) D-Bus
events (PropertiesChanged). So, making a blocking D-Bus call means to wait
for a response and return it, while queuing all messages that are received
in the meantime.
Basically there are three ways how a synchronous API on NMClient could behave:
1) the call just calls g_dbus_connection_call_sync(). This means
that libnm sends a D-Bus request via GDBusConnection, and blockingly
waits for the response. All D-Bus messages that get received in the
meantime are queued in the GMainContext that belongs to NMClient.
That means, none of these D-Bus events are processed until we
iterate the GMainContext after the call returns. The effect is,
that NMClient (and all cached objects in there) are unaffected by
the D-Bus request.
Most of the synchronous API calls in libnm are of this kind.
The problem is that the strict ordering of D-Bus events gets
violated.
For some API this is not an immediate problem. Take for example
nm_device_wifi_request_scan(). The call merely blockingly tells
NetworkManager to start scanning, but since NetworkManager's D-Bus
API does not directly expose any state that tells whether we are
currently scanning, this out of order processing of the D-Bus
request is a small issue.
The problem is more obvious for nm_client_networking_set_enabled().
After calling it, NM_CLIENT_NETWORKING_ENABLED is still unaffected
and unchanged, because the PropertiesChanged signal from D-Bus
is not yet processed.
This means, while you make such a blocking call, NMClient's state
does not change. But usually you perform the synchronous call
to change some state. In this form, the blocking call is not useful,
because NMClient only changes the state after iterating the GMainContext,
and not after the blocking call returns.
2) like 1), but after making the blocking g_dbus_connection_call_sync(),
update the NMClient cache artificially. This is what
nm_manager_check_connectivity() does, to "fix" bgo#784629.
This also has the problem of out-of-order events, but it kinda
solves the problem of not changing the state during the blocking
call. But it does so by hacking the state of the cache. I think
this is really wrong because the state should only be updated from
the ordered stream of D-Bus messages (PropertiesChanged signal and
similar). When libnm decides to modify the state, there may be already
D-Bus messages queued that affect this very state.
3) instead of calling g_dbus_connection_call_sync(), use the
asynchronous g_dbus_connection_call(). If we would use a sepaate
GMainContext for all D-Bus related calls, we could ensure that
while we block for the response, we iterate that internal main context.
This might be nice, because all events are processed in order and
after the blocking call returns, the NMClient state is up to date.
The are problems however: current blocking API does not do this,
so it's a significant change in behavior. Also, it might be
unexpected to the user that during the blocking call the entire
content of NMClient's cache might change and all pointers to the
cache might be invalidated. Also, of course NMClient would invoke
signals for all the changes that happen.
Another problem is that this would be more effort to implement
and it involves a small performance overhead for all D-Bus related
calls (because we have to serialize all events in an internal
GMainContext first and then invoke them on the caller's context).
Also, if the users wants this behavior, they could implement it themself
by running libnm in their own GMainContext. Note that libnm might
have bugs to make that really working, but that should be fixed
instead of adding such synchrnous API behavior.
Read also [1], for why blocking calls are wrong.
[1] https://smcv.pseudorandom.co.uk/2008/11/nonblocking/
So, all possible behaviors for synchronous API have severe behavioural
issues. Mark all this API as deprecated. Also, this serves the purpose of
identifying blocking D-Bus calls in libnm.
Note that "deprecated" here does not really mean that the API is going
to be removed. We don't break API. The user may:
- continue to use this API. It's deprecated, awkward and discouraged,
but if it works, by all means use it.
- use asynchronous API. That's the only sensible way to use D-Bus.
If libnm lacks a certain asynchronous counterpart, it should be
added.
- use GDBusConnection directly. There really isn't anything wrong
with D-Bus or GDBusConnection. This deprecated API is just a wrapper
around g_dbus_connection_call_sync(). You may call it directly
without feeling dirty.
---
The only other remainging API is the synchronous GInitable call for
NMClient. That is an entirely separate beast and not particularly
wrong (from an API point of view).
Note that synchronous API in NMSecretAgentOld, NMVpnPluginOld and
NMVpnServicePlugin as not deprecated here. These types are not part
of the D-Bus cache and while they have similar issues, it's less severe
because they have less state.
the `doc_module` variable has been removed. It was created because
its used in the autotools build file but actually `nm_name` variable
can be used easily.
Different objects used in the documentation target have been grouped
together.
The content file `version.xml`, and different build files are now
added properly.
the `doc_module` variable has been removed. It was created because
its used in the autotools build file but actually `libnm_name`
variable can be used easily.
Different objects used in the documentation target have been grouped
together.
The content file `version.xml` is now added properly.
Functions derived from generators as `configure_file`,
`custom_target` and `i18n.merge_file` can use placeholders like
`@BASENAME@` that removes the extension from the input filename
string.
The output string has been replaced by this placeholder that
allows in some cases the use of less variables.
What's actually needed here is an explaination of how the license
applies along with the explanation where to find the full text.
Also, the libnm documentation was lacking the licensing information
altogether. Fix fixes it too.
gtkdoc-scan supports regular expressions in the --ignore-decorators
command-line option. Since it is easier to use a regexp than grepping
macros from a source file, revert the ugly solution from commit
2d941dc95a ('build: fix errors when building with gtk-doc 1.32').
gtkdoc-scan 1.32 performs stricter checks on structures definitions
and so it complains on:
/build/networkmanager/src/NetworkManager/libnm/./nm-vpn-plugin-old.h:0: warning: partial declaration (struct) : typedef struct {
NM_DEPRECATED_IN_1_2
GObject parent;
} NMVpnPluginOld NM_DEPRECATED_IN_1_2;
because of the unrecognized token 'NM_DEPRECATED_IN_1_2'.
Pass all allowed macros to gtkdoc-scan through the --ignore-decorators
argument.
https://gitlab.gnome.org/GNOME/gtk-doc/issues/98https://gitlab.freedesktop.org/NetworkManager/NetworkManager/issues/238
