17 files changed, 457 insertions, 28 deletions

diff --git a/backend/drm/drm.c b/backend/drm/drm.c
index 96b7d93d..1fceff95 100644
--- a/backend/drm/drm.c
+++ b/backend/drm/drm.c
@@ -452,8 +452,7 @@ static bool wlr_drm_connector_set_mode(struct wlr_output *output,
 		crtc->cursor ? crtc->cursor - drm->cursor_planes : -1);
 
 	conn->state = WLR_DRM_CONN_CONNECTED;
-	conn->output.current_mode = mode;
-	wlr_output_update_size(&conn->output, mode->width, mode->height);
+	wlr_output_update_mode(&conn->output, mode);
 
 	// Since realloc_crtcs can deallocate planes on OTHER outputs,
 	// we actually need to reinitalise any than has changed
diff --git a/backend/drm/renderer.c b/backend/drm/renderer.c
index 8a8d7d1f..00182c59 100644
--- a/backend/drm/renderer.c
+++ b/backend/drm/renderer.c
@@ -24,8 +24,8 @@ bool wlr_drm_renderer_init(struct wlr_drm_backend *drm,
 		return false;
 	}
 
-	if (!wlr_egl_init(&renderer->egl, EGL_PLATFORM_GBM_MESA,
-			GBM_FORMAT_ARGB8888, renderer->gbm)) {
+	if (!wlr_egl_init(&renderer->egl, EGL_PLATFORM_GBM_MESA, renderer->gbm,
+			NULL, GBM_FORMAT_ARGB8888)) {
 		goto error_gbm;
 	}
 
diff --git a/backend/headless/backend.c b/backend/headless/backend.c
new file mode 100644
index 00000000..f95e3897
--- /dev/null
+++ b/backend/headless/backend.c
@@ -0,0 +1,114 @@
+#include <stdlib.h>
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+#include <wlr/util/log.h>
+#include <wlr/interfaces/wlr_output.h>
+#include <wlr/interfaces/wlr_input_device.h>
+#include "backend/headless.h"
+#include "glapi.h"
+
+static bool backend_start(struct wlr_backend *wlr_backend) {
+	struct wlr_headless_backend *backend =
+		(struct wlr_headless_backend *)wlr_backend;
+	wlr_log(L_INFO, "Starting headless backend");
+
+	struct wlr_headless_output *output;
+	wl_list_for_each(output, &backend->outputs, link) {
+		wl_event_source_timer_update(output->frame_timer, output->frame_delay);
+		wlr_output_create_global(&output->wlr_output, backend->display);
+		wl_signal_emit(&backend->backend.events.output_add,
+			&output->wlr_output);
+	}
+
+	struct wlr_headless_input_device *input_device;
+	wl_list_for_each(input_device, &backend->input_devices,
+			wlr_input_device.link) {
+		wl_signal_emit(&backend->backend.events.input_add,
+			&input_device->wlr_input_device);
+	}
+
+	backend->started = true;
+	return true;
+}
+
+static void backend_destroy(struct wlr_backend *wlr_backend) {
+	struct wlr_headless_backend *backend =
+		(struct wlr_headless_backend *)wlr_backend;
+	if (!wlr_backend) {
+		return;
+	}
+
+	wl_list_remove(&backend->display_destroy.link);
+
+	struct wlr_headless_output *output, *output_tmp;
+	wl_list_for_each_safe(output, output_tmp, &backend->outputs, link) {
+		wlr_output_destroy(&output->wlr_output);
+	}
+
+	struct wlr_headless_input_device *input_device, *input_device_tmp;
+	wl_list_for_each_safe(input_device, input_device_tmp,
+			&backend->input_devices, wlr_input_device.link) {
+		wlr_input_device_destroy(&input_device->wlr_input_device);
+	}
+
+	wlr_egl_finish(&backend->egl);
+	free(backend);
+}
+
+static struct wlr_egl *backend_get_egl(struct wlr_backend *wlr_backend) {
+	struct wlr_headless_backend *backend =
+		(struct wlr_headless_backend *)wlr_backend;
+	return &backend->egl;
+}
+
+static const struct wlr_backend_impl backend_impl = {
+	.start = backend_start,
+	.destroy = backend_destroy,
+	.get_egl = backend_get_egl,
+};
+
+static void handle_display_destroy(struct wl_listener *listener, void *data) {
+	struct wlr_headless_backend *backend =
+		wl_container_of(listener, backend, display_destroy);
+	backend_destroy(&backend->backend);
+}
+
+struct wlr_backend *wlr_headless_backend_create(struct wl_display *display) {
+	wlr_log(L_INFO, "Creating headless backend");
+
+	struct wlr_headless_backend *backend =
+		calloc(1, sizeof(struct wlr_headless_backend));
+	if (!backend) {
+		wlr_log(L_ERROR, "Failed to allocate wlr_headless_backend");
+		return NULL;
+	}
+	wlr_backend_init(&backend->backend, &backend_impl);
+	backend->display = display;
+	wl_list_init(&backend->outputs);
+	wl_list_init(&backend->input_devices);
+
+	static const EGLint config_attribs[] = {
+		EGL_SURFACE_TYPE, EGL_PBUFFER_BIT,
+		EGL_ALPHA_SIZE, 0,
+		EGL_BLUE_SIZE, 8,
+		EGL_GREEN_SIZE, 8,
+		EGL_RED_SIZE, 8,
+		EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
+		EGL_NONE,
+	};
+	bool ok = wlr_egl_init(&backend->egl, EGL_PLATFORM_SURFACELESS_MESA, NULL,
+		(EGLint *)config_attribs, 0);
+	if (!ok) {
+		free(backend);
+		return NULL;
+	}
+
+	backend->display_destroy.notify = handle_display_destroy;
+	wl_display_add_destroy_listener(display, &backend->display_destroy);
+
+	return &backend->backend;
+}
+
+bool wlr_backend_is_headless(struct wlr_backend *backend) {
+	return backend->impl == &backend_impl;
+}
diff --git a/backend/headless/input_device.c b/backend/headless/input_device.c
new file mode 100644
index 00000000..05def775
--- /dev/null
+++ b/backend/headless/input_device.c
@@ -0,0 +1,91 @@
+#include <stdlib.h>
+#include <wlr/interfaces/wlr_input_device.h>
+#include <wlr/interfaces/wlr_pointer.h>
+#include <wlr/interfaces/wlr_keyboard.h>
+#include <wlr/interfaces/wlr_touch.h>
+#include <wlr/interfaces/wlr_tablet_tool.h>
+#include <wlr/interfaces/wlr_tablet_pad.h>
+#include <wlr/util/log.h>
+#include "backend/headless.h"
+
+static void input_device_destroy(struct wlr_input_device *wlr_dev) {
+	struct wlr_headless_input_device *device =
+		(struct wlr_headless_input_device *)wlr_dev;
+	wl_signal_emit(&device->backend->backend.events.input_remove, wlr_dev);
+	free(device);
+}
+
+static struct wlr_input_device_impl input_device_impl = {
+	.destroy = input_device_destroy,
+};
+
+struct wlr_input_device *wlr_headless_add_input_device(
+		struct wlr_backend *wlr_backend, enum wlr_input_device_type type) {
+	struct wlr_headless_backend *backend =
+		(struct wlr_headless_backend *)wlr_backend;
+
+	struct wlr_headless_input_device *device =
+		calloc(1, sizeof(struct wlr_headless_input_device));
+	if (device == NULL) {
+		return NULL;
+	}
+	device->backend = backend;
+
+	int vendor = 0;
+	int product = 0;
+	const char *name = "headless";
+	struct wlr_input_device *wlr_device = &device->wlr_input_device;
+	wlr_input_device_init(wlr_device, type, &input_device_impl, name, vendor,
+		product);
+
+	switch (type) {
+	case WLR_INPUT_DEVICE_KEYBOARD:
+		wlr_device->keyboard = calloc(1, sizeof(struct wlr_keyboard));
+		if (wlr_device->keyboard == NULL) {
+			wlr_log(L_ERROR, "Unable to allocate wlr_keyboard");
+			return NULL;
+		}
+		wlr_keyboard_init(wlr_device->keyboard, NULL);
+		break;
+	case WLR_INPUT_DEVICE_POINTER:
+		wlr_device->pointer = calloc(1, sizeof(struct wlr_pointer));
+		if (wlr_device->pointer == NULL) {
+			wlr_log(L_ERROR, "Unable to allocate wlr_pointer");
+			return NULL;
+		}
+		wlr_pointer_init(wlr_device->pointer, NULL);
+		break;
+	case WLR_INPUT_DEVICE_TOUCH:
+		wlr_device->touch = calloc(1, sizeof(struct wlr_touch));
+		if (wlr_device->touch == NULL) {
+			wlr_log(L_ERROR, "Unable to allocate wlr_touch");
+			return NULL;
+		}
+		wlr_touch_init(wlr_device->touch, NULL);
+		break;
+	case WLR_INPUT_DEVICE_TABLET_TOOL:
+		wlr_device->tablet_tool = calloc(1, sizeof(struct wlr_tablet_tool));
+		if (wlr_device->tablet_tool == NULL) {
+			wlr_log(L_ERROR, "Unable to allocate wlr_tablet_tool");
+			return NULL;
+		}
+		wlr_tablet_tool_init(wlr_device->tablet_tool, NULL);
+		break;
+	case WLR_INPUT_DEVICE_TABLET_PAD:
+		wlr_device->tablet_pad = calloc(1, sizeof(struct wlr_tablet_pad));
+		if (wlr_device->tablet_pad == NULL) {
+			wlr_log(L_ERROR, "Unable to allocate wlr_tablet_pad");
+			return NULL;
+		}
+		wlr_tablet_pad_init(wlr_device->tablet_pad, NULL);
+		break;
+	}
+
+	wl_list_insert(&backend->input_devices, &wlr_device->link);
+
+	if (backend->started) {
+		wl_signal_emit(&backend->backend.events.input_add, wlr_device);
+	}
+
+	return wlr_device;
+}
diff --git a/backend/headless/output.c b/backend/headless/output.c
new file mode 100644
index 00000000..9c4ba35e
--- /dev/null
+++ b/backend/headless/output.c
@@ -0,0 +1,146 @@
+#include <stdlib.h>
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+#include <GLES2/gl2.h>
+#include <wlr/interfaces/wlr_output.h>
+#include <wlr/util/log.h>
+#include "backend/headless.h"
+
+static EGLSurface egl_create_surface(struct wlr_egl *egl, unsigned int width,
+		unsigned int height) {
+	EGLint attribs[] = {EGL_WIDTH, width, EGL_HEIGHT, height, EGL_NONE};
+
+	EGLSurface surf = eglCreatePbufferSurface(egl->display, egl->config, attribs);
+	if (surf == EGL_NO_SURFACE) {
+		wlr_log(L_ERROR, "Failed to create EGL surface: %s", egl_error());
+		return EGL_NO_SURFACE;
+	}
+	return surf;
+}
+
+static bool output_set_custom_mode(struct wlr_output *wlr_output, int32_t width,
+		int32_t height, int32_t refresh) {
+	struct wlr_headless_output *output =
+		(struct wlr_headless_output *)wlr_output;
+	struct wlr_headless_backend *backend = output->backend;
+
+	if (output->egl_surface) {
+		eglDestroySurface(backend->egl.display, output->egl_surface);
+	}
+
+	output->egl_surface = egl_create_surface(&backend->egl, width, height);
+	if (output->egl_surface == EGL_NO_SURFACE) {
+		wlr_log(L_ERROR, "Failed to recreate EGL surface");
+		wlr_output_destroy(wlr_output);
+		return false;
+	}
+
+	output->frame_delay = 1000000 / refresh;
+
+	wlr_output_update_custom_mode(&output->wlr_output, width, height, refresh);
+	return true;
+}
+
+static void output_transform(struct wlr_output *wlr_output,
+		enum wl_output_transform transform) {
+	struct wlr_headless_output *output =
+		(struct wlr_headless_output *)wlr_output;
+	output->wlr_output.transform = transform;
+}
+
+static void output_make_current(struct wlr_output *wlr_output) {
+	struct wlr_headless_output *output =
+		(struct wlr_headless_output *)wlr_output;
+	if (!eglMakeCurrent(output->backend->egl.display,
+		output->egl_surface, output->egl_surface,
+		output->backend->egl.context)) {
+		wlr_log(L_ERROR, "eglMakeCurrent failed: %s", egl_error());
+	}
+}
+
+static void output_swap_buffers(struct wlr_output *wlr_output) {
+	// No-op
+}
+
+static void output_destroy(struct wlr_output *wlr_output) {
+	struct wlr_headless_output *output =
+		(struct wlr_headless_output *)wlr_output;
+	wl_signal_emit(&output->backend->backend.events.output_remove,
+		&output->wlr_output);
+
+	wl_list_remove(&output->link);
+
+	eglDestroySurface(output->backend->egl.display, output->egl_surface);
+	free(output);
+}
+
+static const struct wlr_output_impl output_impl = {
+	.set_custom_mode = output_set_custom_mode,
+	.transform = output_transform,
+	.destroy = output_destroy,
+	.make_current = output_make_current,
+	.swap_buffers = output_swap_buffers,
+};
+
+static int signal_frame(void *data) {
+	struct wlr_headless_output *output = data;
+	wl_signal_emit(&output->wlr_output.events.frame, &output->wlr_output);
+	wl_event_source_timer_update(output->frame_timer, output->frame_delay);
+	return 0;
+}
+
+struct wlr_output *wlr_headless_add_output(struct wlr_backend *wlr_backend,
+		unsigned int width, unsigned int height) {
+	struct wlr_headless_backend *backend =
+		(struct wlr_headless_backend *)wlr_backend;
+
+	struct wlr_headless_output *output =
+		calloc(1, sizeof(struct wlr_headless_output));
+	if (output == NULL) {
+		wlr_log(L_ERROR, "Failed to allocate wlr_headless_output");
+		return NULL;
+	}
+	output->backend = backend;
+	wlr_output_init(&output->wlr_output, &backend->backend, &output_impl);
+	struct wlr_output *wlr_output = &output->wlr_output;
+
+	output->egl_surface = egl_create_surface(&backend->egl, width, height);
+	if (output->egl_surface == EGL_NO_SURFACE) {
+		wlr_log(L_ERROR, "Failed to create EGL surface");
+		goto error;
+	}
+
+	output_set_custom_mode(wlr_output, width, height, 60*1000);
+	strncpy(wlr_output->make, "headless", sizeof(wlr_output->make));
+	strncpy(wlr_output->model, "headless", sizeof(wlr_output->model));
+	snprintf(wlr_output->name, sizeof(wlr_output->name), "HEADLESS-%d",
+		wl_list_length(&backend->outputs) + 1);
+
+	if (!eglMakeCurrent(output->backend->egl.display,
+			output->egl_surface, output->egl_surface,
+			output->backend->egl.context)) {
+		wlr_log(L_ERROR, "eglMakeCurrent failed: %s", egl_error());
+		goto error;
+	}
+
+	glViewport(0, 0, wlr_output->width, wlr_output->height);
+	glClearColor(1.0, 1.0, 1.0, 1.0);
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	struct wl_event_loop *ev = wl_display_get_event_loop(backend->display);
+	output->frame_timer = wl_event_loop_add_timer(ev, signal_frame, output);
+
+	wl_list_insert(&backend->outputs, &output->link);
+
+	if (backend->started) {
+		wl_event_source_timer_update(output->frame_timer, output->frame_delay);
+		wlr_output_create_global(wlr_output, backend->display);
+		wl_signal_emit(&backend->backend.events.output_add, wlr_output);
+	}
+
+	return wlr_output;
+
+error:
+	wlr_output_destroy(&output->wlr_output);
+	return NULL;
+}
diff --git a/backend/meson.build b/backend/meson.build
index c9d47317..68d958a7 100644
--- a/backend/meson.build
+++ b/backend/meson.build
@@ -9,6 +9,9 @@ backend_files = files(
 	'drm/properties.c',
 	'drm/renderer.c',
 	'drm/util.c',
+	'headless/backend.c',
+	'headless/output.c',
+	'headless/input_device.c',
 	'libinput/backend.c',
 	'libinput/events.c',
 	'libinput/keyboard.c',
diff --git a/backend/wayland/backend.c b/backend/wayland/backend.c
index 6ebc6615..36fbd8e0 100644
--- a/backend/wayland/backend.c
+++ b/backend/wayland/backend.c
@@ -185,7 +185,7 @@ struct wlr_backend *wlr_wl_backend_create(struct wl_display *display) {
 	}
 
 	wlr_egl_init(&backend->egl, EGL_PLATFORM_WAYLAND_EXT,
-		WL_SHM_FORMAT_ARGB8888, backend->remote_display);
+		backend->remote_display, NULL, WL_SHM_FORMAT_ARGB8888);
 	wlr_egl_bind_display(&backend->egl, backend->local_display);
 
 	backend->local_display_destroy.notify = handle_display_destroy;
diff --git a/backend/wayland/output.c b/backend/wayland/output.c
index fc09903e..d841ec49 100644
--- a/backend/wayland/output.c
+++ b/backend/wayland/output.c
@@ -32,7 +32,7 @@ static bool wlr_wl_output_set_custom_mode(struct wlr_output *_output,
 		int32_t width, int32_t height, int32_t refresh) {
 	struct wlr_wl_backend_output *output = (struct wlr_wl_backend_output *)_output;
 	wl_egl_window_resize(output->egl_window, width, height, 0, 0);
-	wlr_output_update_size(&output->wlr_output, width, height);
+	wlr_output_update_custom_mode(&output->wlr_output, width, height, 0);
 	return true;
 }
 
@@ -229,7 +229,7 @@ static void xdg_toplevel_handle_configure(void *data, struct zxdg_toplevel_v6 *x
 	}
 	// loop over states for maximized etc?
 	wl_egl_window_resize(output->egl_window, width, height, 0, 0);
-	wlr_output_update_size(&output->wlr_output, width, height);
+	wlr_output_update_custom_mode(&output->wlr_output, width, height, 0);
 }
 
 static void xdg_toplevel_handle_close(void *data, struct zxdg_toplevel_v6 *xdg_toplevel) {
@@ -260,7 +260,7 @@ struct wlr_output *wlr_wl_output_create(struct wlr_backend *_backend) {
 	wlr_output_init(&output->wlr_output, &backend->backend, &output_impl);
 	struct wlr_output *wlr_output = &output->wlr_output;
 
-	wlr_output_update_size(wlr_output, 1280, 720);
+	wlr_output_update_custom_mode(wlr_output, 1280, 720, 0);
 	strncpy(wlr_output->make, "wayland", sizeof(wlr_output->make));
 	strncpy(wlr_output->model, "wayland", sizeof(wlr_output->model));
 	snprintf(wlr_output->name, sizeof(wlr_output->name), "WL-%d",
diff --git a/backend/x11/backend.c b/backend/x11/backend.c
index c116e78e..a218c589 100644
--- a/backend/x11/backend.c
+++ b/backend/x11/backend.c
@@ -117,7 +117,8 @@ static bool handle_x11_event(struct wlr_x11_backend *x11, xcb_generic_event_t *e
 	case XCB_CONFIGURE_NOTIFY: {
 		xcb_configure_notify_event_t *ev = (xcb_configure_notify_event_t *)event;
 
-		wlr_output_update_size(&output->wlr_output, ev->width, ev->height);
+		wlr_output_update_custom_mode(&output->wlr_output, ev->width,
+			ev->height, 0);
 
 		// Move the pointer to its new location
 		xcb_query_pointer_cookie_t cookie =
@@ -310,8 +311,8 @@ struct wlr_backend *wlr_x11_backend_create(struct wl_display *display,
 
 	x11->screen = xcb_setup_roots_iterator(xcb_get_setup(x11->xcb_conn)).data;
 
-	if (!wlr_egl_init(&x11->egl, EGL_PLATFORM_X11_KHR,
-			x11->screen->root_visual, x11->xlib_conn)) {
+	if (!wlr_egl_init(&x11->egl, EGL_PLATFORM_X11_KHR, x11->xlib_conn, NULL,
+			x11->screen->root_visual)) {
 		goto error_event;
 	}
 
diff --git a/include/backend/headless.h b/include/backend/headless.h
new file mode 100644
index 00000000..91ff37dd
--- /dev/null
+++ b/include/backend/headless.h
@@ -0,0 +1,35 @@
+#ifndef BACKEND_HEADLESS_H
+#define BACKEND_HEADLESS_H
+
+#include <wlr/backend/interface.h>
+#include <wlr/backend/headless.h>
+#include <wlr/types/wlr_output.h>
+
+struct wlr_headless_backend {
+	struct wlr_backend backend;
+	struct wlr_egl egl;
+	struct wl_display *display;
+	struct wl_list outputs;
+	struct wl_list input_devices;
+	struct wl_listener display_destroy;
+	bool started;
+};
+
+struct wlr_headless_output {
+	struct wlr_output wlr_output;
+
+	struct wlr_headless_backend *backend;
+	struct wl_list link;
+
+	void *egl_surface;
+	struct wl_event_source *frame_timer;
+	int frame_delay; // ms
+};
+
+struct wlr_headless_input_device {
+	struct wlr_input_device wlr_input_device;
+
+	struct wlr_headless_backend *backend;
+};
+
+#endif
diff --git a/include/wlr/backend/headless.h b/include/wlr/backend/headless.h
new file mode 100644
index 00000000..68ad84da
--- /dev/null
+++ b/include/wlr/backend/headless.h
@@ -0,0 +1,14 @@
+#ifndef WLR_BACKEND_HEADLESS_H
+#define WLR_BACKEND_HEADLESS_H
+
+#include <wlr/backend.h>
+#include <wlr/types/wlr_input_device.h>
+
+struct wlr_backend *wlr_headless_backend_create(struct wl_display *display);
+struct wlr_output *wlr_headless_add_output(struct wlr_backend *backend,
+	unsigned int width, unsigned int height);
+struct wlr_input_device *wlr_headless_add_input_device(
+	struct wlr_backend *backend, enum wlr_input_device_type type);
+bool wlr_backend_is_headless(struct wlr_backend *backend);
+
+#endif
diff --git a/include/wlr/interfaces/wlr_output.h b/include/wlr/interfaces/wlr_output.h
index 1cfe7568..6d71f9b6 100644
--- a/include/wlr/interfaces/wlr_output.h
+++ b/include/wlr/interfaces/wlr_output.h
@@ -28,8 +28,10 @@ struct wlr_output_impl {
 void wlr_output_init(struct wlr_output *output, struct wlr_backend *backend,
 	const struct wlr_output_impl *impl);
 void wlr_output_free(struct wlr_output *output);
-void wlr_output_update_size(struct wlr_output *output, int32_t width,
-	int32_t height);
+void wlr_output_update_mode(struct wlr_output *output,
+	struct wlr_output_mode *mode);
+void wlr_output_update_custom_mode(struct wlr_output *output, int32_t width,
+	int32_t height, int32_t refresh);
 struct wl_global *wlr_output_create_global(struct wlr_output *wlr_output,
 	struct wl_display *display);
 void wlr_output_destroy_global(struct wlr_output *wlr_output);
diff --git a/include/wlr/render/egl.h b/include/wlr/render/egl.h
index 67a81f37..bdb8d286 100644
--- a/include/wlr/render/egl.h
+++ b/include/wlr/render/egl.h
@@ -22,7 +22,8 @@ struct wlr_egl {
  *  Initializes an egl context for the given platform and remote display.
  * Will attempt to load all possibly required api functions.
  */
-bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id, void *display);
+bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, void *remote_display,
+	EGLint *config_attribs, EGLint visual_id);
 
 /**
  * Frees all related egl resources, makes the context not-current and
diff --git a/include/wlr/types/wlr_output.h b/include/wlr/types/wlr_output.h
index 037fa515..a974a154 100644
--- a/include/wlr/types/wlr_output.h
+++ b/include/wlr/types/wlr_output.h
@@ -47,6 +47,7 @@ struct wlr_output {
 	char serial[16];
 	float scale;
 	int32_t width, height;
+	int32_t refresh; // mHz
 	int32_t phys_width, phys_height; // mm
 	enum wl_output_subpixel subpixel;
 	enum wl_output_transform transform;
diff --git a/render/egl.c b/render/egl.c
index e895df8d..fe20973c 100644
--- a/render/egl.c
+++ b/render/egl.c
@@ -1,3 +1,4 @@
+#include <assert.h>
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
 #include <GLES2/gl2.h>
@@ -47,7 +48,8 @@ const char *egl_error(void) {
 	}
 }
 
-static bool egl_get_config(EGLDisplay disp, EGLConfig *out, EGLint visual_id) {
+static bool egl_get_config(EGLDisplay disp, EGLint *attribs, EGLConfig *out,
+		EGLint visual_id) {
 	EGLint count = 0, matched = 0, ret;
 
 	ret = eglGetConfigs(disp, NULL, 0, &count);
@@ -58,7 +60,7 @@ static bool egl_get_config(EGLDisplay disp, EGLConfig *out, EGLint visual_id) {
 
 	EGLConfig configs[count];
 
-	ret = eglChooseConfig(disp, NULL, configs, count, &matched);
+	ret = eglChooseConfig(disp, attribs, configs, count, &matched);
 	if (ret == EGL_FALSE) {
 		wlr_log(L_ERROR, "eglChooseConfig failed");
 		return false;
@@ -71,7 +73,7 @@ static bool egl_get_config(EGLDisplay disp, EGLConfig *out, EGLint visual_id) {
 			continue;
 		}
 
-		if (visual == visual_id) {
+		if (!visual_id || visual == visual_id) {
 			*out = configs[i];
 			return true;
 		}
@@ -81,8 +83,8 @@ static bool egl_get_config(EGLDisplay disp, EGLConfig *out, EGLint visual_id) {
 	return false;
 }
 
-bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id,
-		void *remote_display) {
+bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, void *remote_display,
+		EGLint *config_attribs, EGLint visual_id) {
 	if (!load_glapi()) {
 		return false;
 	}
@@ -92,7 +94,12 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id,
 		goto error;
 	}
 
-	egl->display = eglGetPlatformDisplayEXT(platform, remote_display, NULL);
+	if (platform == EGL_PLATFORM_SURFACELESS_MESA) {
+		assert(remote_display == NULL);
+		egl->display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
+	} else {
+		egl->display = eglGetPlatformDisplayEXT(platform, remote_display, NULL);
+	}
 	if (egl->display == EGL_NO_DISPLAY) {
 		wlr_log(L_ERROR, "Failed to create EGL display: %s", egl_error());
 		goto error;
@@ -104,7 +111,7 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id,
 		goto error;
 	}
 
-	if (!egl_get_config(egl->display, &egl->config, visual_id)) {
+	if (!egl_get_config(egl->display, config_attribs, &egl->config, visual_id)) {
 		wlr_log(L_ERROR, "Failed to get EGL config");
 		goto error;
 	}
diff --git a/rootston/main.c b/rootston/main.c
index 58e5a5e5..d17079d3 100644
--- a/rootston/main.c
+++ b/rootston/main.c
@@ -4,6 +4,7 @@
 #include <unistd.h>
 #include <wayland-server.h>
 #include <wlr/backend.h>
+#include <wlr/backend/headless.h>
 #include <wlr/render.h>
 #include <wlr/render/gles2.h>
 #include <wlr/util/log.h>
@@ -29,7 +30,11 @@ int main(int argc, char **argv) {
 	assert(server.wl_display = wl_display_create());
 	assert(server.wl_event_loop = wl_display_get_event_loop(server.wl_display));
 
-	assert(server.backend = wlr_backend_autocreate(server.wl_display));
+	//assert(server.backend = wlr_backend_autocreate(server.wl_display));
+	assert(server.backend = wlr_headless_backend_create(server.wl_display));
+	wlr_headless_add_output(server.backend, 1280, 720);
+	wlr_headless_add_input_device(server.backend, WLR_INPUT_DEVICE_KEYBOARD);
+	wlr_headless_add_input_device(server.backend, WLR_INPUT_DEVICE_POINTER);
 
 	assert(server.renderer = wlr_gles2_renderer_create(server.backend));
 	server.data_device_manager =
diff --git a/types/wlr_output.c b/types/wlr_output.c
index de1d29df..923f8f52 100644
--- a/types/wlr_output.c
+++ b/types/wlr_output.c
@@ -39,7 +39,7 @@ static void wl_output_send_to_resource(struct wl_resource *resource) {
 		if (wl_list_length(&output->modes) == 0) {
 			// Output has no mode, send the current width/height
 			wl_output_send_mode(resource, WL_OUTPUT_MODE_CURRENT,
-				output->width, output->height, 0);
+				output->width, output->height, output->refresh);
 		}
 	}
 	if (version >= WL_OUTPUT_SCALE_SINCE_VERSION) {
@@ -65,9 +65,9 @@ static void wlr_output_send_current_mode_to_resource(
 		wl_output_send_mode(resource, flags | WL_OUTPUT_MODE_CURRENT,
 			mode->width, mode->height, mode->refresh);
 	} else {
-		// Output has no mode, send the current width/height
+		// Output has no mode
 		wl_output_send_mode(resource, WL_OUTPUT_MODE_CURRENT, output->width,
-			output->height, 0);
+			output->height, output->refresh);
 	}
 	if (version >= WL_OUTPUT_DONE_SINCE_VERSION) {
 		wl_output_send_done(resource);
@@ -192,9 +192,17 @@ bool wlr_output_set_custom_mode(struct wlr_output *output, int32_t width,
 	return result;
 }
 
-void wlr_output_update_size(struct wlr_output *output, int32_t width,
-		int32_t height) {
-	if (output->width == width && output->height == height) {
+void wlr_output_update_mode(struct wlr_output *output,
+		struct wlr_output_mode *mode) {
+	output->current_mode = mode;
+	wlr_output_update_custom_mode(output, mode->width, mode->height,
+		mode->refresh);
+}
+
+void wlr_output_update_custom_mode(struct wlr_output *output, int32_t width,
+		int32_t height, int32_t refresh) {
+	if (output->width == width && output->height == height &&
+			output->refresh == refresh) {
 		return;
 	}
 
@@ -202,6 +210,8 @@ void wlr_output_update_size(struct wlr_output *output, int32_t width,
 	output->height = height;
 	wlr_output_update_matrix(output);
 
+	output->refresh = refresh;
+
 	struct wl_resource *resource;
 	wl_resource_for_each(resource, &output->wl_resources) {
 		wlr_output_send_current_mode_to_resource(resource);