Open X11 Window

backend/backend.c

@@ -80,7 +80,7 @@ struct wlr_backend *wlr_backend_autocreate(struct wl_display *display) {
 
 	const char *x11_display = getenv("DISPLAY");
 	if (x11_display) {
-		return wlr_x11_backend_create(x11_display);
+		return wlr_x11_backend_create(display, x11_display);
 	}
 
 	// Attempt DRM+libinput

backend/x11/backend.c

@@ -1,30 +1,119 @@
 #include <stdbool.h>
+#include <stdlib.h>
+#include <xcb/xcb.h>
+#include <X11/Xlib-xcb.h>
+#include <wayland-server.h>
 #include <wlr/backend/interface.h>
 #include <wlr/backend/x11.h>
 #include <wlr/egl.h>
+#include <wlr/util/log.h>
 #include "backend/x11.h"
 
-struct wlr_backend *wlr_x11_backend_create(const char *display) {
+static struct wlr_backend_impl backend_impl;
+
+int x11_event(int fd, uint32_t mask, void *data) {
+	struct wlr_x11_backend *x11 = data;
+
+	xcb_generic_event_t *event = xcb_wait_for_event(x11->xcb_conn);
+	if (!event) {
+		return 0;
+	}
+
+	switch (event->response_type) {
+	case XCB_EXPOSE:
+		break;
+	case XCB_KEY_PRESS:
+		break;
+	default:
+		wlr_log(L_INFO, "Unknown event");
+		break;
+	}
+
+	free(event);
+	return 0;
+}
+
+struct wlr_backend *wlr_x11_backend_create(struct wl_display *display,
+		const char *x11_display) {
+	struct wlr_x11_backend *x11 = calloc(1, sizeof(*x11));
+	if (!x11) {
+		return NULL;
+	}
+
+	wlr_backend_init(&x11->backend, &backend_impl);
+
+	x11->xlib_conn = XOpenDisplay(x11_display);
+	if (!x11->xlib_conn) {
+		wlr_log(L_ERROR, "Failed to open X connection");
+		return NULL;
+	}
+
+	x11->xcb_conn = XGetXCBConnection(x11->xlib_conn);
+	if (!x11->xcb_conn || xcb_connection_has_error(x11->xcb_conn)) {
+		wlr_log(L_ERROR, "Failed to open xcb connection");
+		goto error;
+	}
+
+	int fd = xcb_get_file_descriptor(x11->xcb_conn);
+	struct wl_event_loop *ev = wl_display_get_event_loop(display);
+	x11->event_source = wl_event_loop_add_fd(ev, fd, WL_EVENT_READABLE, x11_event, x11);
+	if (!x11->event_source) {
+		wlr_log(L_ERROR, "Could not create event source");
+		goto error;
+	}
+
+	return &x11->backend;
+
+error:
+	xcb_disconnect(x11->xcb_conn);
+	XCloseDisplay(x11->xlib_conn);
+	free(x11);
 	return NULL;
 }
 
 static bool wlr_x11_backend_start(struct wlr_backend *backend) {
-	return false;
+	struct wlr_x11_backend *x11 = (struct wlr_x11_backend *)backend;
+
+	xcb_screen_t *screen = xcb_setup_roots_iterator(xcb_get_setup(x11->xcb_conn)).data;
+	uint32_t mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK;
+	uint32_t values[2] = {
+		screen->white_pixel,
+		XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_KEY_PRESS
+	};
+
+	x11->win = xcb_generate_id(x11->xcb_conn);
+
+	xcb_create_window(x11->xcb_conn, XCB_COPY_FROM_PARENT, x11->win, screen->root,
+		0, 0, 1024, 768, 1, XCB_WINDOW_CLASS_INPUT_OUTPUT,
+		screen->root_visual, mask, values);
+
+	xcb_map_window(x11->xcb_conn, x11->win);
+	xcb_flush(x11->xcb_conn);
+
+	return true;
 }
 
 static void wlr_x11_backend_destroy(struct wlr_backend *backend) {
+	if (!backend) {
+		return;
+	}
+
+	struct wlr_x11_backend *x11 = (struct wlr_x11_backend *)backend;
+
+	xcb_disconnect(x11->xcb_conn);
+	free(x11);
 }
 
 struct wlr_egl *wlr_x11_backend_get_egl(struct wlr_backend *backend) {
 	return NULL;
 }
 
+bool wlr_backend_is_x11(struct wlr_backend *backend) {
+	return backend->impl == &backend_impl;
+}
+
 static struct wlr_backend_impl backend_impl = {
 	.start = wlr_x11_backend_start,
 	.destroy = wlr_x11_backend_destroy,
 	.get_egl = wlr_x11_backend_get_egl,
 };
-
-bool wlr_backend_is_x11(struct wlr_backend *backend) {
-	return backend->impl == &backend_impl;
-}

include/backend/x11.h

@@ -1,8 +1,20 @@
 #ifndef WLR_X11_H
 #define WLR_X11_H
 
+#include <xcb/xcb.h>
+#include <X11/Xlib-xcb.h>
+#include <wayland-server.h>
+#include <wlr/egl.h>
+
 struct wlr_x11_backend {
 	struct wlr_backend backend;
+
+	Display *xlib_conn;
+	xcb_connection_t *xcb_conn;
+	xcb_window_t win;
+
+	struct wlr_egl egl;
+	struct wl_event_source *event_source;
 };
 
 #endif

include/wlr/backend/x11.h

@@ -1,10 +1,12 @@
 #ifndef WLR_BACKEND_X11_H
 #define WLR_BACKEND_X11_H
 
-#include <wlr/backend.h>
 #include <stdbool.h>
+#include <wayland-server.h>
+#include <wlr/backend.h>
 
-struct wlr_backend *wlr_x11_backend_create(const char *display);
+struct wlr_backend *wlr_x11_backend_create(struct wl_display *display,
+	const char *x11_display);
 
 bool wlr_backend_is_x11(struct wlr_backend *backend);
 

meson.build

@@ -45,6 +45,7 @@ udev           = dependency('libudev')
 pixman         = dependency('pixman-1')
 xcb            = dependency('xcb')
 xcb_composite  = dependency('xcb-composite')
+x11_xcb        = dependency('x11-xcb')
 libcap         = dependency('libcap', required: false)
 systemd        = dependency('libsystemd', required: false)
 elogind        = dependency('libelogind', required: false)
@@ -85,6 +86,7 @@ wlr_deps = [
 	pixman,
 	xcb,
 	xcb_composite,
+	x11_xcb,
 	libcap,
 	systemd,
 	math,