backend: wait for session to become active
#include <wlr/backend/x11.h>
#endif
+#define WAIT_SESSION_TIMEOUT 10000 // ms
+
void wlr_backend_init(struct wlr_backend *backend,
const struct wlr_backend_impl *impl) {
assert(backend);
@@ -106,6 +108,52 @@ struct wlr_session *wlr_backend_get_session(struct wlr_backend *backend) {
return NULL;
}
+static uint64_t get_current_time_ms(void) {
+ struct timespec ts = {0};
+ clock_gettime(CLOCK_MONOTONIC, &ts);
+ return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
+}
+
+static struct wlr_session *session_create_and_wait(struct wl_display *disp) {
+ struct wlr_session *session = wlr_session_create(disp);
+
+ if (!session) {
+ wlr_log(WLR_ERROR, "Failed to start a session");
+ return NULL;
+ }
+
+ if (!session->active) {
+ wlr_log(WLR_INFO, "Waiting for a session to become active");
+
+ uint64_t started_at = get_current_time_ms();
+ uint64_t timeout = WAIT_SESSION_TIMEOUT;
+ struct wl_event_loop *event_loop =
+ wl_display_get_event_loop(session->display);
+
+ while (!session->active) {
+ int ret = wl_event_loop_dispatch(event_loop, (int)timeout);
+ if (ret < 0) {
+ wlr_log_errno(WLR_ERROR, "Failed to wait for session active: "
+ "wl_event_loop_dispatch failed");
+ return NULL;
+ }
+
+ uint64_t now = get_current_time_ms();
+ if (now >= started_at + WAIT_SESSION_TIMEOUT) {
+ break;
+ }
+ timeout = started_at + WAIT_SESSION_TIMEOUT - now;
+ }
+
+ if (!session->active) {
+ wlr_log(WLR_ERROR, "Timeout waiting session to become active");
+ return NULL;
+ }
+ }
+
+ return session;
+}
+
clockid_t wlr_backend_get_presentation_clock(struct wlr_backend *backend) {
if (backend->impl->get_presentation_clock) {
return backend->impl->get_presentation_clock(backend);
@@ -269,7 +317,7 @@ static struct wlr_backend *attempt_backend_by_name(struct wl_display *display,
} else if (strcmp(name, "drm") == 0 || strcmp(name, "libinput") == 0) {
// DRM and libinput need a session
if (!*session) {
- *session = wlr_session_create(display);
+ *session = session_create_and_wait(display);
if (!*session) {
wlr_log(WLR_ERROR, "failed to start a session");
return NULL;
@@ -368,7 +416,7 @@ struct wlr_backend *wlr_backend_autocreate(struct wl_display *display) {
#endif
// Attempt DRM+libinput
- multi->session = wlr_session_create(display);
+ multi->session = session_create_and_wait(display);
if (!multi->session) {
wlr_log(WLR_ERROR, "Failed to start a DRM session");
wlr_backend_destroy(backend);
