Implement config/state file handling

Make methods to load_config and load/save state. For now the config
and state directories are the same but it might not be. Implement
the search path for all config/state files as:

  $XDG_CONFIG_HOME/[$prefix]/$name
  $HOME/.config/[$prefix]/$name
  $PIPEWIRE_CONFIG_DIR/pipewire/[$prefix]/$name
  /etc/pipewire/[$prefix]/$name

Make some config files for jack and RT clients. Make pw-cat use the
client-rt config.

Use core state and config management in media-session.
Move all session manager state and config files to the build dir and
set the PIPEWIRE_CONFIG_DIR to this build dir.

src/daemon/client-rt.conf.in

@@ -0,0 +1,63 @@
+# Daemon config file for PipeWire RT clients version @VERSION@ #
+
+properties = {
+    ## Configure properties in the system.
+    #mem.warn-mlock =		false
+    #mem.allow-mlock =		true
+    #mem.mlock-all =		false
+    #log.level =		2
+}
+
+spa-libs = {
+    ## <factory-name regex> = <library-name>
+    #
+    # Used to find spa factory names. It maps an spa factory name
+    # regular expression to a library name that should contain
+    # that factory.
+    #
+    audio.convert* = 	audioconvert/libspa-audioconvert
+    support.* =		support/libspa-support
+}
+
+modules = {
+    ##  <module-name> = { [args = { <key>=<value> ... }]
+    #                     [flags = [ [ifexists] [nofail] ]}
+    #
+    # Loads a module with the given parameters.
+    # If ifexists is given, the module is ignored when it is not found.
+    # If nofail is given, module initialization failures are ignored.
+    #
+    # Uses RTKit to boost the data thread priority.
+    libpipewire-module-rtkit  = {
+        args = {
+            #nice.level = -11
+            #rt.prio = 20
+            #rt.time.soft = 200000
+            #rt.time.hard = 200000
+	}
+        flags = [ ifexists nofail ]
+    }
+
+    # The native communication protocol.
+    libpipewire-module-protocol-native = null
+
+    # Allows creating nodes that run in the context of the
+    # client. Is used by all clients that want to provide
+    # data to PipeWire.
+    libpipewire-module-client-node = null
+
+    # Allows creating devices that run in the context of the
+    # client. Is used by the session manager.
+    libpipewire-module-client-device = null
+
+    # Makes a factory for wrapping nodes in an adapter with a
+    # converter and resampler.
+    libpipewire-module-adapter = null
+
+    # Allows applications to create metadata objects. It creates
+    # a factory for Metadata objects.
+    libpipewire-module-metadata = null
+
+    # Provides factories to make session manager objects.
+    libpipewire-module-session-manager = null
+}

src/daemon/jack.conf.in

@@ -0,0 +1,52 @@
+# Daemon config file for PipeWire JACK clients version @VERSION@ #
+
+properties = {
+    ## Configure properties in the system.
+    #mem.warn-mlock =		false
+    #mem.allow-mlock =		true
+    #mem.mlock-all =		false
+    #log.level =		2
+}
+
+spa-libs = {
+    ## <factory-name regex> = <library-name>
+    #
+    # Used to find spa factory names. It maps an spa factory name
+    # regular expression to a library name that should contain
+    # that factory.
+    #
+    support.* =		support/libspa-support
+}
+
+modules = {
+    ##  <module-name> = { [args = { <key>=<value> ... }]
+    #                     [flags = [ [ifexists] [nofail] ]}
+    #
+    # Loads a module with the given parameters.
+    # If ifexists is given, the module is ignored when it is not found.
+    # If nofail is given, module initialization failures are ignored.
+    #
+    #
+    # Uses RTKit to boost the data thread priority.
+    libpipewire-module-rtkit  = {
+        args = {
+            #nice.level = -11
+            #rt.prio = 20
+            #rt.time.soft = 200000
+            #rt.time.hard = 200000
+	}
+        flags = [ ifexists nofail ]
+    }
+
+    # The native communication protocol.
+    libpipewire-module-protocol-native = null
+
+    # Allows creating nodes that run in the context of the
+    # client. Is used by all clients that want to provide
+    # data to PipeWire.
+    libpipewire-module-client-node = null
+
+    # Allows applications to create metadata objects. It creates
+    # a factory for Metadata objects.
+    libpipewire-module-metadata = null
+}

src/daemon/media-session.d/meson.build

@@ -0,0 +1,21 @@
+conf_files = [
+  [ 'bluez-monitor.conf', 'bluez-monitor.conf' ],
+  [ 'v4l2-monitor.conf', 'v4l2-monitor.conf' ],
+  [ 'media-session.conf', 'media-session.conf' ],
+  [ 'alsa-monitor.conf', 'alsa-monitor.conf' ],
+  [ 'with-jack', 'with-jack' ],
+  [ 'with-pulseaudio', 'with-pulseaudio' ],
+]
+
+foreach c : conf_files
+  configure_file(input : c.get(0),
+                 output : c.get(1),
+                 configuration : conf_config,
+                 install_dir : join_paths(conf_install_dir, 'media-session.d'))
+endforeach
+
+install_data(
+  sources : [
+    'with-jack',
+    'with-pulseaudio' ],
+  install_dir : join_paths(conf_install_dir, 'media-session.d'))

src/daemon/meson.build

@@ -14,36 +14,27 @@ conf_config.set('media_session_path', join_paths(pipewire_bindir, 'pipewire-medi
 conf_config.set('pipewire_pulse_path', join_paths(pipewire_bindir, 'pipewire-pulse'))
 conf_install_dir = join_paths(get_option('sysconfdir'), 'pipewire')
 
-install_data(
-  sources : [
-    'media-session.d/with-jack',
-    'media-session.d/with-pulseaudio',
-    'media-session.d/bluez-monitor.conf',
-    'media-session.d/v4l2-monitor.conf',
-    'media-session.d/media-session.conf',
-    'media-session.d/alsa-monitor.conf' ],
-  install_dir : join_paths(conf_install_dir, 'media-session.d'))
-
 conf_config_uninstalled = conf_config
 conf_config_uninstalled.set('media_session_path',
   join_paths(meson.build_root(), 'src', 'examples', 'pipewire-media-session'))
 conf_config_uninstalled.set('pipewire_pulse_path',
   join_paths(meson.build_root(), 'src', 'daemon', 'pipewire-pulse'))
 
-configure_file(input : 'pipewire.conf.in',
-               output : 'pipewire.conf',
-               configuration : conf_config,
-               install_dir : conf_install_dir)
 
-configure_file(input : 'client.conf.in',
-               output : 'client.conf',
-               configuration : conf_config,
-               install_dir : conf_install_dir)
+conf_files = [
+  [ 'pipewire.conf.in', 'pipewire.conf' ],
+  [ 'client.conf.in', 'client.conf' ],
+  [ 'client-rt.conf.in', 'client-rt.conf' ],
+  [ 'jack.conf.in', 'jack.conf' ],
+  [ 'pipewire-pulse.conf.in', 'pipewire-pulse.conf' ]
+]
 
-configure_file(input : 'pipewire-pulse.conf.in',
-               output : 'pipewire-pulse.conf',
-               configuration : conf_config,
-               install_dir : conf_install_dir)
+foreach c : conf_files
+  configure_file(input : c.get(0),
+                 output : c.get(1),
+                 configuration : conf_config,
+                 install_dir : conf_install_dir)
+endforeach
 
 configure_file(input : 'pipewire.conf.in',
                output : 'pipewire-uninstalled.conf',
@@ -81,6 +72,7 @@ executable('pipewire-pulse',
 #  )
 #endif
 
+subdir('media-session.d')
 if get_option('systemd') and systemd.found()
   subdir('systemd')
 endif