Generic bind funcs

Author: jgillich

go.work

@@ -0,0 +1,6 @@
+go 1.22.0
+
+use (
+	.
+	./pkg
+)

pkg/core/glib/bind.go

@@ -0,0 +1,74 @@
+package glib
+
+import (
+	"reflect"
+	"sync"
+	"unsafe"
+
+	"github.com/diamondburned/gotk4/pkg/core/gbox"
+)
+
+// #include <glib.h>
+// #include <glib-object.h>
+// #include "glib.go.h"
+import "C"
+
+var bindingNames sync.Map // map[reflect.Type]C.GQuark
+
+// Associate value with object
+func Bind[T any](obj Objector, value T) {
+	object := BaseObject(obj)
+	name := bindingName[T]()
+
+	ptr := C.gpointer(gbox.Assign(value))
+
+	C.g_object_set_data_full(object.native(), (*C.gchar)(name), ptr, (*[0]byte)(C._gotk4_data_destroy))
+}
+
+// Disassociate value from object
+func Unbind[T any](obj Objector) {
+	name := bindingName[T]()
+
+	ptr := C.g_object_steal_data(BaseObject(obj).native(), (*C.gchar)(name))
+	defer gbox.Delete(uintptr(ptr))
+}
+
+// Obtain value associated with object
+func Bounded[T any](obj Objector) *T {
+	name := bindingName[T]()
+
+	ptr := C.g_object_get_data(BaseObject(obj).native(), name)
+
+	value, ok := gbox.Get(uintptr(ptr)).(T)
+	if !ok {
+		return nil
+	}
+
+	return &value
+}
+
+func bindingName[T any]() *C.gchar {
+	t := reflect.TypeFor[T]()
+
+	if v, ok := bindingNames.Load(t); ok {
+		quark := v.(C.GQuark)
+		return C.g_quark_to_string(quark)
+	}
+
+	name := "_gotk4_" + t.String()
+
+	nameC := C.CString(name)
+	defer C.free(unsafe.Pointer(nameC))
+
+	quark := C.g_quark_from_string(nameC)
+	if v, lost := bindingNames.LoadOrStore(t, quark); lost {
+		quark = v.(C.GQuark)
+	}
+
+	return C.g_quark_to_string(quark)
+}
+
+//export _gotk4_data_destroy
+func _gotk4_data_destroy(ptr C.gpointer) {
+	gbox.Delete(uintptr(ptr))
+}

pkg/core/glib/glib.go

@@ -589,9 +589,6 @@ type Objector interface {
 	NotifyProperty(string, func()) SignalHandle
 	ObjectProperty(string) interface{}
 	SetObjectProperty(string, interface{})
-	ObjectData(string) interface{}
-	SetObjectData(string, interface{})
-	StealObjectData(name string) interface{}
 	FreezeNotify()
 	ThawNotify()
 	StopEmission(string)
@@ -871,41 +868,6 @@ func (v *Object) NotifyProperty(property string, f func()) SignalHandle {
 	)
 }
 
-// Gets a named field from the objects table of associations
-func (v *Object) ObjectData(name string) interface{} {
-	cstr := C.CString(name)
-	defer C.free(unsafe.Pointer(cstr))
-
-	ptr := C.g_object_get_data(v.native(), (*C.gchar)(cstr))
-	runtime.KeepAlive(v)
-
-	return gbox.Get(uintptr(ptr))
-}
-
-// Each object carries around a table of associations from strings to pointers. This function lets you set an association.
-func (v *Object) SetObjectData(name string, value interface{}) {
-	cstr := C.CString(name)
-	defer C.free(unsafe.Pointer(cstr))
-
-	ptr := C.gpointer(gbox.Assign(value))
-
-	C.g_object_set_data(v.native(), (*C.gchar)(cstr), ptr)
-	runtime.KeepAlive(v)
-}
-
-// Remove a specified datum from the object’s data associations
-func (v *Object) StealObjectData(name string) interface{} {
-	cstr := C.CString(name)
-	defer C.free(unsafe.Pointer(cstr))
-
-	ptr := C.g_object_steal_data(v.native(), (*C.gchar)(cstr))
-	defer gbox.Delete(uintptr(ptr))
-
-	runtime.KeepAlive(v)
-
-	return gbox.Get(uintptr(ptr))
-}
-
 // FreezeNotify increases the freeze count on object. If the freeze count is
 // non-zero, the emission of “notify” signals on object is stopped. The signals
 // are queued until the freeze count is decreased to zero. Duplicate

pkg/core/glib/glib.go.h

@@ -109,4 +109,6 @@ static void init_i18n(const char *domain, const char *dir) {
 
 static const char *localize(const char *string) { return _(string); }
 
+extern void _gotk4_data_destroy(gpointer ptr);
+
 #endif

pkg/core/test/glib_test.go

@@ -1,21 +1,27 @@
 package test
 
 import (
+	"runtime"
 	"testing"
 
-	"github.com/diamondburned/gotk4/pkg/gtk/v4"
+	"github.com/diamondburned/gotk4/pkg/core/glib"
+	"github.com/diamondburned/gotk4/pkg/gio/v2"
 )
 
 func TestObjectData(t *testing.T) {
-	gtk.Init()
+	testObjectData(t)
 
-	label := gtk.NewLabel("label")
+	runtime.GC()
+}
+
+func testObjectData(t *testing.T) {
+	app := gio.NewApplication("foo.bar", gio.ApplicationFlagsNone)
 
-	label.SetObjectData("foo", "bar")
+	glib.Bind(app, "foo")
 
-	if label.ObjectData("foo") != "bar" {
+	if value := glib.Bounded[string](app); value == nil || *value != "foo" {
 		t.Fatal("returned data did not match expected data")
 	}
 
-	label.StealObjectData("foo")
+	glib.Unbind[string](app)
 }