From 718d006a63f773c42106494e823250c48942cf08 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Tue, 17 Sep 2013 17:39:54 +0200 Subject: logind: listen actively for session devices Session compositors need access to fbdev, DRM and evdev devices if they control a session. To make logind pass them to sessions, we need to listen for them actively. However, we avoid creating new seats for non master-of-seat devices. Only once a seat is created, we start remembering all other session devices. If the last master-device is removed (even if there are other non-master devices still available), we destroy the seat. This is the current behavior, but we need to explicitly implement it now as there may be non-master devices in the seat->devices list. Unlike master devices, we don't care whether our list of non-master devices is complete. We don't export this list but use it only as cache if sessions request these devices. Hence, if a session requests a device that is not in the list, we will simply look it up. However, once a session requested a device, we must be notified of "remove" udev events. So we must link the devices somehow into the device-list. Regarding the implementation, we now sort the device list by the "master" flag. This guarantees that master devices are at the front and non-master devices at the tail of the list. Thus, we can easily test whether a seat has a master device attached. --- src/login/logind.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'src/login/logind.h') diff --git a/src/login/logind.h b/src/login/logind.h index e9838a8afd..1a97351fff 100644 --- a/src/login/logind.h +++ b/src/login/logind.h @@ -57,9 +57,10 @@ struct Manager { LIST_HEAD(User, user_gc_queue); struct udev *udev; - struct udev_monitor *udev_seat_monitor, *udev_vcsa_monitor, *udev_button_monitor; + struct udev_monitor *udev_seat_monitor, *udev_device_monitor, *udev_vcsa_monitor, *udev_button_monitor; int udev_seat_fd; + int udev_device_fd; int udev_vcsa_fd; int udev_button_fd; @@ -121,6 +122,7 @@ struct Manager { enum { FD_SEAT_UDEV, + FD_DEVICE_UDEV, FD_VCSA_UDEV, FD_BUTTON_UDEV, FD_CONSOLE, @@ -132,7 +134,7 @@ enum { Manager *manager_new(void); void manager_free(Manager *m); -int manager_add_device(Manager *m, const char *sysfs, Device **_device); +int manager_add_device(Manager *m, const char *sysfs, bool master, Device **_device); int manager_add_button(Manager *m, const char *name, Button **_button); int manager_add_seat(Manager *m, const char *id, Seat **_seat); int manager_add_session(Manager *m, const char *id, Session **_session); -- cgit v1.2.3-54-g00ecf