internal/pipewire: export Registry::Destroy

This handles the error returned by Sync.

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

internal/pipewire/core.go

@@ -641,6 +641,37 @@ func (registry *Registry) destroy(id Int) error {
 	)
 }
 
+// Destroy tries to destroy the global object with id.
+func (registry *Registry) Destroy(id Int) error {
+	if err := registry.destroy(id); err != nil {
+		return err
+	}
+	destroySeq := registry.ctx.currentSeq()
+
+	err := registry.ctx.GetCore().Sync()
+	if err == nil {
+		return nil
+	}
+
+	var coreError *CoreError
+	if proxyErrors, ok := err.(ProxyConsumeError); !ok ||
+		len(proxyErrors) != 1 ||
+		!errors.As(proxyErrors[0], &coreError) ||
+		coreError == nil ||
+		coreError.ID != registry.ID ||
+		coreError.Sequence != destroySeq {
+		return err
+	}
+
+	switch syscall.Errno(-coreError.Result) {
+	case syscall.EPERM:
+		return &PermissionError{registry.ID, coreError.Message}
+
+	default:
+		return coreError
+	}
+}
+
 // An UnsupportedObjectTypeError is the name of a type not known by the server [Registry].
 type UnsupportedObjectTypeError string
 

internal/pipewire/pipewire.go

@@ -636,7 +636,7 @@ func (ctx *Context) roundtrip() (err error) {
 }
 
 // currentSeq returns the current sequence number.
-// This must only be called from eventProxy.consume.
+// This must only be called immediately after queueing a message.
 func (ctx *Context) currentSeq() Int { return ctx.sequence - 1 }
 
 // currentRemoteSeq returns the current remote sequence number.
@@ -786,6 +786,18 @@ func (ctx *Context) Close() (err error) {
 	}
 }
 
+// A PermissionError describes an error emitted by the server when trying to
+// perform an operation that the client has no permission for.
+type PermissionError struct {
+	// The id of the resource (proxy if emitted by the client) that is in error.
+	ID Int `json:"id"`
+	// An error message.
+	Message string `json:"message"`
+}
+
+func (*PermissionError) Unwrap() error   { return syscall.EPERM }
+func (e *PermissionError) Error() string { return e.Message }
+
 // Remote is the environment (sic) with the remote name.
 const Remote = "PIPEWIRE_REMOTE"
 

internal/pipewire/pipewire_test.go

@@ -870,6 +870,11 @@ func TestContextErrors(t *testing.T) {
 		}, "new Registry::Global event for PipeWire:Interface:NewInvalid stepping on previous id 2989 for PipeWire:Interface:Invalid"},
 
 		{"UnknownGlobalIDRemoveError", pipewire.UnknownGlobalIDRemoveError(0xbad), "Registry::GlobalRemove event targets unknown id 2989"},
+
+		{"PermissionError", &pipewire.PermissionError{
+			ID:      2,
+			Message: "no permission to destroy 0",
+		}, "no permission to destroy 0"},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {