add xevent.

server/internal/desktop/manager.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"m1k1o/neko/internal/config"
+	"m1k1o/neko/internal/desktop/xevent"
 	"m1k1o/neko/internal/desktop/xorg"
 	"m1k1o/neko/internal/types"
 
@@ -40,6 +41,17 @@ func (manager *DesktopManagerCtx) Start() {
 		Str("screen_size", fmt.Sprintf("%dx%d@%d", manager.config.ScreenWidth, manager.config.ScreenHeight, manager.config.ScreenRate)).
 		Msgf("setting initial screen size")
 
+	go xevent.EventLoop(manager.config.Display)
+
+	manager.OnEventError(func(error_code uint8, message string, request_code uint8, minor_code uint8) {
+		manager.logger.Warn().
+			Uint8("error_code", error_code).
+			Str("message", message).
+			Uint8("request_code", request_code).
+			Uint8("minor_code", minor_code).
+			Msg("X event error occurred")
+	})
+
 	manager.wg.Add(1)
 
 	go func() {

server/internal/desktop/xevent.go

@@ -0,0 +1,33 @@
+package desktop
+
+import "m1k1o/neko/internal/desktop/xevent"
+
+func (manager *DesktopManagerCtx) OnCursorChanged(listener func(serial uint64)) {
+	xevent.Emmiter.On("cursor-changed", func(payload ...any) {
+		listener(payload[0].(uint64))
+	})
+}
+
+func (manager *DesktopManagerCtx) OnClipboardUpdated(listener func()) {
+	xevent.Emmiter.On("clipboard-updated", func(payload ...any) {
+		listener()
+	})
+}
+
+func (manager *DesktopManagerCtx) OnFileChooserDialogOpened(listener func()) {
+	xevent.Emmiter.On("file-chooser-dialog-opened", func(payload ...any) {
+		listener()
+	})
+}
+
+func (manager *DesktopManagerCtx) OnFileChooserDialogClosed(listener func()) {
+	xevent.Emmiter.On("file-chooser-dialog-closed", func(payload ...any) {
+		listener()
+	})
+}
+
+func (manager *DesktopManagerCtx) OnEventError(listener func(error_code uint8, message string, request_code uint8, minor_code uint8)) {
+	xevent.Emmiter.On("event-error", func(payload ...any) {
+		listener(payload[0].(uint8), payload[1].(string), payload[2].(uint8), payload[3].(uint8))
+	})
+}

server/internal/desktop/xevent/xevent.c

@@ -0,0 +1,123 @@
+#include "xevent.h"
+
+static int XEventError(Display *display, XErrorEvent *event) {
+  char message[100];
+
+  int error;
+  error = XGetErrorText(display, event->error_code, message, sizeof(message));
+  if (error) {
+    goXEventError(event, "Could not get error message.");
+  } else {
+    goXEventError(event, message);
+  }
+
+  return 1;
+}
+
+void XEventLoop(char *name) {
+  Display *display = XOpenDisplay(name);
+  Window root = RootWindow(display, 0);
+
+  int xfixes_event_base, xfixes_error_base;
+  if (!XFixesQueryExtension(display, &xfixes_event_base, &xfixes_error_base)) {
+    return;
+  }
+
+  Atom WM_WINDOW_ROLE = XInternAtom(display, "WM_WINDOW_ROLE", 1);
+  Atom XA_CLIPBOARD = XInternAtom(display, "CLIPBOARD", 0);
+  XFixesSelectSelectionInput(display, root, XA_CLIPBOARD, XFixesSetSelectionOwnerNotifyMask);
+  XFixesSelectCursorInput(display, root, XFixesDisplayCursorNotifyMask);
+  XSelectInput(display, root, SubstructureNotifyMask);
+
+  XSync(display, 0);
+  XSetErrorHandler(XEventError);
+
+  while (goXEventActive()) {
+    XEvent event;
+    XNextEvent(display, &event);
+
+    // XFixesDisplayCursorNotify
+    if (event.type == xfixes_event_base + 1) {
+      XFixesCursorNotifyEvent notifyEvent = *((XFixesCursorNotifyEvent *) &event);
+      if (notifyEvent.subtype == XFixesDisplayCursorNotify) {
+        goXEventCursorChanged(notifyEvent);
+        continue;
+      }
+    }
+
+    // XFixesSelectionNotifyEvent
+    if (event.type == xfixes_event_base + XFixesSelectionNotify) {
+      XFixesSelectionNotifyEvent notifyEvent = *((XFixesSelectionNotifyEvent *) &event);
+      if (notifyEvent.subtype == XFixesSetSelectionOwnerNotify && notifyEvent.selection == XA_CLIPBOARD) {
+        goXEventClipboardUpdated();
+        continue;
+      }
+    }
+
+    // ConfigureNotify
+    if (event.type == ConfigureNotify) {
+      Window window = event.xconfigure.window;
+
+      char *name;
+      XFetchName(display, window, &name);
+
+      XTextProperty role;
+      XGetTextProperty(display, window, &role, WM_WINDOW_ROLE);
+
+      goXEventConfigureNotify(display, window, name, role.value);
+      XFree(name);
+      continue;
+    }
+
+    // UnmapNotify
+    if (event.type == UnmapNotify) {
+      Window window = event.xunmap.window;
+      goXEventUnmapNotify(window);
+      continue;
+    }
+  }
+
+  XCloseDisplay(display);
+}
+
+void XFileChooserHide(Display *display, Window window) {
+  Window root = RootWindow(display, 0);
+
+  // The WM_TRANSIENT_FOR property is defined by the [ICCCM] for managed windows.
+  // This specification extends the use of the property to override-redirect windows.
+  // If an override-redirect is a pop-up on behalf of another window, then the Client
+  // SHOULD set WM_TRANSIENT_FOR on the override-redirect to this other window.
+  //
+  // As an example, a Client should set WM_TRANSIENT_FOR on dropdown menus to the
+  // toplevel application window that contains the menubar.
+
+  // Remove WM_TRANSIENT_FOR
+  Atom WM_TRANSIENT_FOR = XInternAtom(display, "WM_TRANSIENT_FOR", 0);
+  XDeleteProperty(display, window, WM_TRANSIENT_FOR);
+
+  // Add _NET_WM_STATE_BELOW
+  XClientMessageEvent clientMessageEvent;
+  memset(&clientMessageEvent, 0, sizeof(clientMessageEvent));
+
+  // window  = the respective client window
+  // message_type = _NET_WM_STATE
+  // format = 32
+  // data.l[0] = the action, as listed below
+  //   _NET_WM_STATE_REMOVE  0 // remove/unset property
+  //   _NET_WM_STATE_ADD     1 // add/set property
+  //   _NET_WM_STATE_TOGGLE  2 // toggle property 
+  // data.l[1] = first property to alter
+  // data.l[2] = second property to alter
+  // data.l[3] = source indication
+  // other data.l[] elements = 0
+
+  clientMessageEvent.type         = ClientMessage;
+  clientMessageEvent.window       = window;
+  clientMessageEvent.message_type = XInternAtom(display, "_NET_WM_STATE", 0);
+  clientMessageEvent.format       = 32;
+  clientMessageEvent.data.l[0]    = 1;
+  clientMessageEvent.data.l[1]    = XInternAtom(display, "_NET_WM_STATE_BELOW", 0);
+  clientMessageEvent.data.l[3]    = 1;
+
+  XSendEvent(display, root, 0, SubstructureRedirectMask | SubstructureNotifyMask, (XEvent *)&clientMessageEvent);
+}

server/internal/desktop/xevent/xevent.go

@@ -0,0 +1,84 @@
+package xevent
+
+/*
+#cgo LDFLAGS: -lX11 -lXfixes
+
+#include "xevent.h"
+*/
+import "C"
+
+import (
+	"strings"
+	"time"
+	"unsafe"
+
+	"github.com/kataras/go-events"
+)
+
+var Emmiter events.EventEmmiter
+var file_chooser_dialog_window uint32 = 0
+
+func init() {
+	Emmiter = events.New()
+}
+
+func EventLoop(display string) {
+	displayUnsafe := C.CString(display)
+	defer C.free(unsafe.Pointer(displayUnsafe))
+
+	C.XEventLoop(displayUnsafe)
+}
+
+//export goXEventCursorChanged
+func goXEventCursorChanged(event C.XFixesCursorNotifyEvent) {
+	Emmiter.Emit("cursor-changed", uint64(event.cursor_serial))
+}
+
+//export goXEventClipboardUpdated
+func goXEventClipboardUpdated() {
+	Emmiter.Emit("clipboard-updated")
+}
+
+//export goXEventConfigureNotify
+func goXEventConfigureNotify(display *C.Display, window C.Window, name *C.char, role *C.char) {
+	if C.GoString(role) != "GtkFileChooserDialog" {
+		return
+	}
+
+	// TODO: Refactor. Right now processing of this dialog relies on identifying
+	// via its name. When that changes to role, this condition should be removed.
+	if !strings.HasPrefix(C.GoString(name), "Open File") {
+		return
+	}
+
+	C.XFileChooserHide(display, window)
+
+	// Because first dialog is not put properly to background
+	time.Sleep(10 * time.Millisecond)
+	C.XFileChooserHide(display, window)
+
+	if file_chooser_dialog_window == 0 {
+		file_chooser_dialog_window = uint32(window)
+		Emmiter.Emit("file-chooser-dialog-opened")
+	}
+}
+
+//export goXEventUnmapNotify
+func goXEventUnmapNotify(window C.Window) {
+	if uint32(window) != file_chooser_dialog_window {
+		return
+	}
+
+	file_chooser_dialog_window = 0
+	Emmiter.Emit("file-chooser-dialog-closed")
+}
+
+//export goXEventError
+func goXEventError(event *C.XErrorEvent, message *C.char) {
+	Emmiter.Emit("event-error", uint8(event.error_code), C.GoString(message), uint8(event.request_code), uint8(event.minor_code))
+}
+
+//export goXEventActive
+func goXEventActive() C.int {
+	return C.int(1)
+}

server/internal/desktop/xevent/xevent.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <X11/Xutil.h>
+#include <X11/Xatom.h>
+#include <X11/Xlib.h>
+#include <X11/extensions/Xfixes.h>
+#include <stdlib.h>
+#include <string.h>
+
+extern void goXEventCursorChanged(XFixesCursorNotifyEvent event);
+extern void goXEventClipboardUpdated();
+extern void goXEventConfigureNotify(Display *display, Window window, char *name, char *role);
+extern void goXEventUnmapNotify(Window window);
+extern void goXEventError(XErrorEvent *event, char *message);
+extern int goXEventActive();
+
+static int XEventError(Display *display, XErrorEvent *event);
+void XEventLoop(char *display);
+
+void XFileChooserHide(Display *display, Window window);

server/internal/types/desktop.go

@@ -61,4 +61,11 @@ type DesktopManager interface {
 	GetKeyboardModifiers() KeyboardModifiers
 	GetCursorImage() *CursorImage
 	GetScreenshotImage() *image.RGBA
+
+	// xevent
+	OnCursorChanged(listener func(serial uint64))
+	OnClipboardUpdated(listener func())
+	OnFileChooserDialogOpened(listener func())
+	OnFileChooserDialogClosed(listener func())
+	OnEventError(listener func(error_code uint8, message string, request_code uint8, minor_code uint8))
 }