internal/outcome: look up pipewire-pulse path

This is for setting up the pipewire-pulse container in shim, for #29.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/outcome/sppipewire.go

@@ -3,20 +3,33 @@ package outcome
 import (
 	"encoding/gob"
 
+	"hakurei.app/container/check"
 	"hakurei.app/hst"
 	"hakurei.app/internal/pipewire"
 )
 
-func init() { gob.Register(spPipeWireOp{}) }
+const pipewirePulseName = "pipewire-pulse"
+
+func init() { gob.Register(new(spPipeWireOp)) }
 
 // spPipeWireOp exports the PipeWire server to the container via SecurityContext.
 // Runs after spRuntimeOp.
-type spPipeWireOp struct{}
+type spPipeWireOp struct {
+	// Path to pipewire-pulse server. Populated during toSystem if DirectPipeWire is false.
+	CompatServerPath *check.Absolute
+}
 
-func (s spPipeWireOp) toSystem(state *outcomeStateSys) error {
+func (s *spPipeWireOp) toSystem(state *outcomeStateSys) error {
 	if state.et&hst.EPipeWire == 0 {
 		return errNotEnabled
 	}
+	if !state.directPipeWire {
+		if n, err := state.k.lookPath(pipewirePulseName); err != nil {
+			return &hst.AppError{Step: "look up " + pipewirePulseName, Err: err}
+		} else if s.CompatServerPath, err = check.NewAbs(n); err != nil {
+			return err
+		}
+	}
 
 	appId := state.appId
 	if appId == "" {
@@ -27,10 +40,10 @@ func (s spPipeWireOp) toSystem(state *outcomeStateSys) error {
 	return nil
 }
 
-func (s spPipeWireOp) toContainer(state *outcomeStateParams) error {
-	innerPath := state.runtimeDir.Append(pipewire.PW_DEFAULT_REMOTE)
-	state.env[pipewire.Remote] = innerPath.String()
-	state.params.Bind(state.instancePath().Append("pipewire"), innerPath, 0)
+func (s *spPipeWireOp) toContainer(state *outcomeStateParams) error {
+		innerPath := state.runtimeDir.Append(pipewire.PW_DEFAULT_REMOTE)
+		state.env[pipewire.Remote] = innerPath.String()
+		state.params.Bind(state.instancePath().Append("pipewire"), innerPath, 0)
 
 	return nil
 }