Separate the session manager in a monitor and policy part.
The monitor manages the devices and endpoints.
The policy watches the nodes/ports/clients and applies the policy
of linking them.
Because both now have a separate connection, we can remove some
hacks in the protocol. When a remote was both the implementer and
user of an object we could get in a deadlock when the user was
blocked waiting and the implementator was blocked sending a reply.
We used to un-busy a client when it was expecting a reply from a
ping or sync for this reason.
Add and use some more keys for the endpoints and streams.
Metadata allows apps to attach properties to objects that can be
read by other apps.
Not complete yet, properties should be removed when the object is
removed.
For flatpaks we need to be able to support older v0 protocol clients.
To handle this we have:
- the connection detects an old client when it receives the first
message. It can do this by checking the sequence number, on old
versions it contains the message size and is never 0, on new
clients the sequence number is 0.
- We add a new signal at the start of the connection with the detected
version number. This installs the right version of the core proxy.
We also move the binding of the client until the hello message is
received. This way we can have a new client connect (portal),
hand over the connection to an old client, which then removes the
client binding again in the hello request with a v0 version.
There are some changes to the passing of fds in v0 vs v3 which need
to investigated some more.
- bump version of our interfaces to 3. This makes it possible to
have v0 and v3 protocol marshal functions.
- Add version number in the proxy. This is mostly automatically done
internally based on the version numbers the library is compiled
with. Where the version number was in the API before, it is now
actually used to look up the right protocol marshal functions. For
Proxies there is usually just 1 version, the current one. It is the
server that will support different versions.
- Add v0 compat marshal functions to convert from and to v0 format.
This has some complications. v0 has a type map it keeps in sync
with the server. For this we have a static type map with mappings
to our own v3 types. Pods are mostly the same except for objects
that used to have arbitrary pods in v0 vs spa_pod_prop in v3. Also
convert between v0 spa_pod_prop and v3 spa_pod_choice.
Formats and commands are also slightly different so handle those
mappings as well.
We only have marshal functions for the server side (resource)
v0 functions.
- Add v0 compatible client-node again. It's a bit tricky to map, v0
client-node basically lets the server to the mixing and teeing
and just does the processing of the internal node.
When the port receives a format, look if we can find a mixer for it
and configure it.
Use the float32 mono mixer when possible.
Use the new pw_buffers in the link.
Let the port allocate buffers between the mixer and node when
requested.
The client-node doesn't need a mixer because mixing is done on the
client.
Remove all mixer and buffer negotiation code from adapter because
it is now done at the port level.
Remove the monitor API, we can use the device API for it. Make sure
we support creating devices (like alsa) from another device (udev).
Use new object.id to store the object id in the object properties. Use
the port.id/node.id etc to make relations to other objects.
Reorganize some things, let the clients update the segment info
in their own activation, then let the server merge it. This avoids
clients stepping on eachother. When looping through the clients,
copy the segment info when we encounter its owner.
Remove the list of segment owners to the activation. This is better
than in the activation because we can then just keep one list of
owners.
Remove the NONBLOCK flag from the eventfd so that we can do blocking
reads as well.
Just keep a reposition owner in the driver activation. This points
to the node that has the reposition info. This avoid complicated
synchronization to keep multiple nodes from stepping on eachother.
Now they can just prepare the reposition info in their activation and
set themselves as the reposition owner. The last one who succeeds
wins.
After we grab the lockfile we should remove the socket when it
exists so that we can bind again. This should solve startup
problems after a crash, which left the socket around and caused
bind failures.
Move fields from the io_position to io_segment. The segment contains
the mapping between raw clock time and stream time in various
formats. We keep an array of pending segments available in the
io_position field so clients can anticipate changes.
Make looping a flag in the segment instead of a state.
Prepare for segment masters. These will be registered clients that
are responsible for updating parts of the extended segment info.
Add namespace to some defines.
Getting SO_PEERSEC on distributions that do not use a LSM by default,
results always in a "protocol error", which is just annoying and not
a real problem for pipewire's operation.
Remove the parent_id from the global event. Remove the parent
and owner from the global object.
Use properties instead to mark parents and owners of objects.
Properties are easier to control for client exported objects and
usually a simple parent/child is not enough. For example, a client
exported node has the client as a parent but also the factory that
created the node.
Keep the output port buffers in a special mix info. They should
stay there even when the mix is removed and should only be cleared
explicitly with a NULL Format or 0 use_buffers.
When we destroy a proxy, mark it as zombie until the server removes
the id. This way we can still keep the id locked with a valid entry
and remove it later.
