Merge pull request #496 from emersion/headless-backend

Headless backend

1 files changed, 114 insertions, 0 deletions

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;
+}