New wireplumber config

.config/wireplumber/scripts/linking/find-defined-target.lua

@@ -0,0 +1,131 @@
+-- WirePlumber
+--
+-- Copyright © 2022 Collabora Ltd.
+--
+-- SPDX-License-Identifier: MIT
+--
+-- Check if the target node is defined explicitly.
+-- This defination can be done in two ways.
+-- 1. "node.target"/"target.object" in the node properties
+-- 2. "target.node"/"target.object" in the default metadata
+
+lutils = require ("linking-utils")
+cutils = require ("common-utils")
+log = Log.open_topic ("s-linking")
+
+SimpleEventHook {
+  name = "linking/find-defined-target",
+  before = "linking/prepare-link",
+  interests = {
+    EventInterest {
+      Constraint { "event.type", "=", "select-target" },
+    },
+  },
+  execute = function (event)
+    local source, om, si, si_props, si_flags, target =
+        lutils:unwrap_select_target_event (event)
+
+    -- bypass the hook if the target is already picked up
+    if target then
+      return
+    end
+
+    log:info (si, string.format ("handling item %d: %s (%s)", si.id,
+        tostring (si_props ["node.name"]), tostring (si_props ["node.id"])))
+
+    local metadata = Settings.get_boolean ("linking.allow-moving-streams") and
+        cutils.get_default_metadata_object ()
+    local dont_fallback = cutils.parseBool (si_props ["node.dont-fallback"])
+    local dont_move = cutils.parseBool (si_props ["node.dont-move"])
+    local target_key
+    local target_value = nil
+    local node_defined = false
+    local target_picked = nil
+
+    if si_props ["target.object"] ~= nil then
+      target_value = si_props ["target.object"]
+      target_key = "object.serial"
+      node_defined = true
+    elseif si_props ["node.target"] ~= nil then
+      target_value = si_props ["node.target"]
+      target_key = "node.id"
+      node_defined = true
+    end
+
+    if metadata and not dont_move then
+      local id = metadata:find (si_props ["node.id"], "target.object")
+      if id ~= nil then
+        target_value = id
+        target_key = "object.serial"
+        node_defined = false
+      else
+        id = metadata:find (si_props ["node.id"], "target.node")
+        if id ~= nil then
+          target_value = id
+          target_key = "node.id"
+          node_defined = false
+        end
+      end
+    end
+
+    if target_value == "-1" then
+      target_picked = false
+      target = nil
+    elseif target_value and tonumber (target_value) then
+      target = om:lookup {
+        type = "SiLinkable",
+        Constraint { target_key, "=", target_value },
+      }
+      if target and lutils.canLink (si_props, target) then
+        target_picked = true
+      end
+    elseif target_value then
+      for lnkbl in om:iterate { type = "SiLinkable" } do
+        local target_props = lnkbl.properties
+        if (target_props ["node.name"] == target_value or
+            target_props ["object.path"] == target_value) and
+            target_props ["item.node.direction"] == cutils.getTargetDirection (si_props) and
+            lutils.canLink (si_props, lnkbl) then
+          target_picked = true
+          target = lnkbl
+          break
+        end
+      end
+    end
+
+    local can_passthrough, passthrough_compatible
+    if target then
+      passthrough_compatible, can_passthrough =
+      lutils.checkPassthroughCompatibility (si, target)
+      if not passthrough_compatible then
+        target = nil
+      end
+    end
+
+    si_flags.has_defined_target = false
+    if target_picked and target then
+      log:info (si,
+        string.format ("... defined target picked: %s (%s), can_passthrough:%s",
+          tostring (target.properties ["node.name"]),
+          tostring (target.properties ["node.id"]),
+          tostring (can_passthrough)))
+      si_flags.has_node_defined_target = node_defined
+      si_flags.can_passthrough = can_passthrough
+      si_flags.has_defined_target = true
+      event:set_data ("target", target)
+    elseif target_value and dont_fallback then
+      -- send error to client and destroy node if linger is not set
+      local linger = cutils.parseBool (si_props ["node.linger"])
+      if not linger then
+        local node = si:get_associated_proxy ("node")
+        lutils.sendClientError (event, node, -2, "defined target not found")
+        node:request_destroy ()
+        log:info(si, "... destroyed node as defined target was not found")
+      else
+        log:info(si, "... waiting for defined target as dont-fallback is set")
+      end
+      event:stop_processing ()
+    end
+
+  end
+}:register ()