Each component can optionally "provide" a feature, which is basically
a string that describes the feature (ex. "support.dbus"). If the
component loads successfully, the feature is marked as provided and
can be tested for its presence with wp_core_test_feature()
Now that we have proper module load order, we can have this shared
dbus connection in a module instead of the library. The module has
to be loaded before any other modules that need it, obviously.
There is no reason to return the component object... all components
are supposed to be long-lived objects that are referenced by the
registry and there is API to find them. The caller is only interested
in the success or failure of the operation.
Do this in wp_core_load_component() and let the component loaders worry
only about creating the object.
Also run the main loop in tests while loading components, to ensure
that the async operation finishes before continuing execution. GTask
makes sure to make the operation async always, by emitting the callback
from an idle GSource.
Regarding the core parameter, the case used to be that WpComponentLoader
was a WpPlugin, so it had a reference to the core internally, but since
this is no longer a requirement, we need to pass this explicitly
Syslog calls this level "notice" and I prefer it because we use it
to display significant messages that are not warnings, but they
are not really "standard", as GLib wants them to be. There is nothing
"standard" about log messages in general.
Also, make these notice messages be enabled at debug level 2, together
with warnings. The default log.level is 2 and it is a good idea to show
notices by default too.
Finally, show them in the log with "N" and also change criticals to be
shown with "E", meaning "error"... Then promote G_LOG_LEVEL_ERROR
messages to be shown with "F", meaning "fatal", because in fact these
messages are always fatal and always call abort(). Still, keep the term
"critical" in the functions to make sure that whoever uses them is aware
that this level is only for critical conditions and not suitable to
display any kind of error.
This allows lua scripts to work with log topics. A topic must be
opened at the top of the file, in global scope, and subsequently
all log commands should be executed on the returned object instead
of the Log global table
The intention is to make checks for enabled log topics faster.
Every topic has its own structure that is statically defined in the file
where the logs are printed from. The structure is initialized transparently
when it is first used and it contains all the log level flags for the levels
that this topic should print messages. It is then checked on the wp_log()
macro before printing the message.
Topics from SPA/PipeWire are also handled natively, so messages are printed
directly without checking if the topic is enabled, since the PipeWire and SPA
macros do the checking themselves.
Messages coming from GLib are checked inside the handler.
An internal WpLogFields object is used to manage the state of each log
message, populating all the fields appropriately from the place they
are coming from (wp_log, spa_log, glib log), formatting the message and
then printing it. For printing to the journald, we still use the glib
message handler, converting all the needed fields to GLogField on demand.
That message handler does not do any checks for the topic or the level, so
we can just call it to send the message.
This change completely refactors the way components are loaded in wireplumber:
- The module_init() function must return a GObject now. This object is either
a WpPlugin or a WpSiFactory in the current modules.
- When the component loader initializes a module, it automatically registers
the WpPlugin or WpSiFactory with their respective methods. There is no need
to register the WpPlugin or WpSiFactory in the module now.
- The wp_core_load_component() API has been refactored to be asynchronows. This
allows the component loader to automatically activate WpPlugin objects, and
therefore allows the application to directly get the WpPlugin without having
to find it. This simplifies a lot of things.
- The 'ifexists' and 'nofail' component flags now work even if the respective
WpPlugin could not be activated.
- The code that loads components in main.c has also been simplified a lot,
and the option to load dangling components has also been removed.
This removes both the policy-virtual-client.lua and policy-virtual-device.lua
scripts, and creates a new linking/find-virtual-target.lua script to link
clients with virtual session items if one of them can be found. In addition to
this, this patch also ports the policy-virtual-client-links.lua into a new
scripts/rescan-virtual-links.lua to use the event stack. The idea is for the
scripts/link-target.lua to create all links but only activate non virtual links,
and for the scripts/rescan-virtual-links.lua to activate/deactivate virtual
links based on role priorities.
This patch also moves nested configuration objects that are not considered
settings from the wireplumber.settings section to its own configuration
section (eg the rules array, the spa plugin properties, etc...). This allows
those objects to be merged with other same sections defined in other files.
When in error, attempt to execute a step called "error", if it exists.
This is rarely needed, but it might be useful in some cases to cleanup
some state, rolling back changes, when something fails.
Call the event "rescan-for-<context>", where <context> is either
"linking" or "default-nodes" and can be expanded in the future.
Add an additional hook in default-nodes to trigger the
rescan-for-default-nodes event when sources and sinks come and go.
When the core is shutting down, the weak reference to it is cleared before
we have a change to use it, but it's ok because everything is getting destroyed
at this point, including the hook that we want to unregister.
But keep the additional comments and debug statement improvements.
Also, merge the stuff from common.h, which was previously shared
with m-default-nodes.
* Remove entirely the hook priority numbers and use before/after dependencies
* Split the WpEvent code out of WpEventDispatcher
* Add methods on WpEvent to interface with it from the WpEventDispatcher.
As a bonus, we can now also implement tooling to inspect which hooks would
in theory run for an event and write tests around that
* Removed some internal debugging facilities and log calls, will redo it later.
* Using spa_list now for the list of hooks, to reduce the number of allocations
happening in the "hook collection" algorithm
* Switched some internal data to use g_new0 instead of g_slice_new0
* Added g_free to free WpEvent structures... surprisingly, we were leaking them
before
It is better to have type-specific event names to minimize the amount
of constraint string matches we do on hooks, as most hooks (if not all)
are interested on specific types of objects only.
Similarly, use a different object manager for each object type to
minimize the performance impact of iterations and lookups, as all
such actions are interested in only 1 object type every time.
Port all existing hooks to the new event names and the get-object-manager API.
This avoids having to determine the subject type prior to pushing
an event from lua code and makes the call more convenient
Also add a debug statement to trace calls to push_event
This can be used anywhere else in the codebase to push a "rescan-session"
event, making sure that there is only one such event pushed on the stack,
no matter how many times this is called.
