1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright (C) 2014 David Herrmann <dh.herrmann@gmail.com>
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU Lesser General Public License as published by
10 the Free Software Foundation; either version 2.1 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 Lesser General Public License for more details.
18 You should have received a copy of the GNU Lesser General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 #include <libevdev/libevdev.h>
28 #include <systemd/sd-bus.h>
29 #include <systemd/sd-event.h>
34 #include "idev-internal.h"
36 #include "udev-util.h"
39 typedef struct idev_evdev idev_evdev;
40 typedef struct unmanaged_evdev unmanaged_evdev;
41 typedef struct managed_evdev managed_evdev;
45 struct libevdev *evdev;
47 sd_event_source *fd_src;
48 sd_event_source *idle_src;
50 bool unsync : 1; /* not in-sync with kernel */
51 bool resync : 1; /* re-syncing with kernel */
55 struct unmanaged_evdev {
60 struct managed_evdev {
64 sd_bus_slot *slot_pause_device;
65 sd_bus_slot *slot_resume_device;
66 sd_bus_slot *slot_take_device;
68 bool requested : 1; /* TakeDevice() was sent */
69 bool acquired : 1; /* TakeDevice() was successful */
72 #define idev_evdev_from_element(_e) container_of((_e), idev_evdev, element)
73 #define unmanaged_evdev_from_element(_e) \
74 container_of(idev_evdev_from_element(_e), unmanaged_evdev, evdev)
75 #define managed_evdev_from_element(_e) \
76 container_of(idev_evdev_from_element(_e), managed_evdev, evdev)
78 #define IDEV_EVDEV_INIT(_vtable, _session) ((idev_evdev){ \
79 .element = IDEV_ELEMENT_INIT((_vtable), (_session)), \
83 #define IDEV_EVDEV_NAME_MAX (8 + DECIMAL_STR_MAX(unsigned) * 2)
85 static const idev_element_vtable unmanaged_evdev_vtable;
86 static const idev_element_vtable managed_evdev_vtable;
88 static int idev_evdev_resume(idev_evdev *evdev, int dev_fd);
89 static void idev_evdev_pause(idev_evdev *evdev, bool release);
92 * Virtual Evdev Element
93 * The virtual evdev element is the base class of all other evdev elements. It
94 * uses libevdev to access the kernel evdev API. It supports asynchronous
95 * access revocation, re-syncing if events got dropped and more.
96 * This element cannot be used by itself. There must be a wrapper around it
97 * which opens a file-descriptor and passes it to the virtual evdev element.
100 static void idev_evdev_name(char *out, dev_t devnum) {
101 /* @out must be at least of size IDEV_EVDEV_NAME_MAX */
102 sprintf(out, "evdev/%u:%u", major(devnum), minor(devnum));
105 static int idev_evdev_feed_resync(idev_evdev *evdev) {
107 .type = IDEV_DATA_RESYNC,
108 .resync = evdev->resync,
111 return idev_element_feed(&evdev->element, &data);
114 static int idev_evdev_feed_evdev(idev_evdev *evdev, struct input_event *event) {
116 .type = IDEV_DATA_EVDEV,
117 .resync = evdev->resync,
123 return idev_element_feed(&evdev->element, &data);
126 static void idev_evdev_hup(idev_evdev *evdev) {
128 * On HUP, we close the current fd via idev_evdev_pause(). This drops
129 * the event-sources from the main-loop and effectively puts the
130 * element asleep. If the HUP is part of a hotplug-event, a following
131 * udev-notification will destroy the element. Otherwise, the HUP is
132 * either result of access-revokation or a serious error.
133 * For unmanaged devices, we should never receive HUP (except for
134 * unplug-events). But if we do, something went seriously wrong and we
135 * shouldn't try to be clever.
136 * Instead, we simply stay asleep and wait for the device to be
137 * disabled and then re-enabled (or closed and re-opened). This will
138 * re-open the device node and restart the device.
139 * For managed devices, a HUP usually means our device-access was
140 * revoked. In that case, we simply put the device asleep and wait for
141 * logind to notify us once the device is alive again. logind also
142 * passes us a new fd. Hence, we don't have to re-enable the device.
144 * Long story short: The only thing we have to do here, is close() the
145 * file-descriptor and remove it from the main-loop. Everything else is
146 * handled via additional events we receive.
149 idev_evdev_pause(evdev, true);
152 static int idev_evdev_io(idev_evdev *evdev) {
153 idev_element *e = &evdev->element;
154 struct input_event ev;
159 * Read input-events via libevdev until the input-queue is drained. In
160 * case we're disabled, don't do anything. The input-queue might
161 * overflow, but we don't care as we have to resync after wake-up,
163 * TODO: libevdev should give us a hint how many events to read. We
164 * really want to avoid starvation, so we shouldn't read forever in
165 * case we cannot keep up with the kernel.
166 * TODO: Make sure libevdev always reports SYN_DROPPED to us, regardless
167 * whether any event was synced afterwards.
170 flags = LIBEVDEV_READ_FLAG_NORMAL;
173 /* immediately resync, even if in sync right now */
174 evdev->unsync = false;
175 evdev->resync = false;
176 flags = LIBEVDEV_READ_FLAG_NORMAL;
177 r = libevdev_next_event(evdev->evdev, flags | LIBEVDEV_READ_FLAG_FORCE_SYNC, &ev);
178 if (r < 0 && r != -EAGAIN) {
181 } else if (r != LIBEVDEV_READ_STATUS_SYNC) {
182 log_debug("idev-evdev: %s/%s: cannot force resync: %d",
183 e->session->name, e->name, r);
186 r = libevdev_next_event(evdev->evdev, flags, &ev);
189 if (evdev->resync && r == -EAGAIN) {
191 evdev->resync = false;
192 flags = LIBEVDEV_READ_FLAG_NORMAL;
193 } else if (r == -EAGAIN) {
194 /* no data available */
199 } else if (r == LIBEVDEV_READ_STATUS_SYNC) {
202 r = idev_evdev_feed_evdev(evdev, &ev);
209 evdev->resync = true;
210 flags = LIBEVDEV_READ_FLAG_SYNC;
211 r = idev_evdev_feed_resync(evdev);
219 r = idev_evdev_feed_evdev(evdev, &ev);
228 log_debug("idev-evdev: %s/%s: error on data event: %s",
229 e->session->name, e->name, strerror(-error));
233 idev_evdev_hup(evdev);
234 return 0; /* idev_evdev_hup() handles the error so discard it */
237 static int idev_evdev_event_fn(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
238 idev_evdev *evdev = userdata;
240 /* fetch data as long as EPOLLIN is signalled */
241 if (revents & EPOLLIN)
242 return idev_evdev_io(evdev);
244 if (revents & (EPOLLHUP | EPOLLERR))
245 idev_evdev_hup(evdev);
250 static int idev_evdev_idle_fn(sd_event_source *s, void *userdata) {
251 idev_evdev *evdev = userdata;
254 * The idle-event is raised whenever we have to re-sync the libevdev
255 * state from the kernel. We simply call into idev_evdev_io() which
256 * flushes the state and re-syncs it if @unsync is set.
257 * State has to be synced whenever our view of the kernel device is
258 * out of date. This is the case when we open the device, if the
259 * kernel's receive buffer overflows, or on other exceptional
260 * situations. Events during re-syncs must be forwarded to the upper
261 * layers so they can update their view of the device. However, such
262 * events must only be handled passively, as they might be out-of-order
263 * and/or re-ordered. Therefore, we mark them as 'sync' events.
269 return idev_evdev_io(evdev);
272 static void idev_evdev_destroy(idev_evdev *evdev) {
274 assert(evdev->fd < 0);
276 libevdev_free(evdev->evdev);
280 static void idev_evdev_enable(idev_evdev *evdev) {
282 assert(evdev->fd_src);
283 assert(evdev->idle_src);
287 if (evdev->fd < 0 || evdev->element.n_open < 1 || !evdev->element.enabled)
290 evdev->running = true;
291 sd_event_source_set_enabled(evdev->fd_src, SD_EVENT_ON);
292 sd_event_source_set_enabled(evdev->idle_src, SD_EVENT_ONESHOT);
295 static void idev_evdev_disable(idev_evdev *evdev) {
297 assert(evdev->fd_src);
298 assert(evdev->idle_src);
303 evdev->running = false;
304 idev_evdev_feed_resync(evdev);
305 sd_event_source_set_enabled(evdev->fd_src, SD_EVENT_OFF);
306 sd_event_source_set_enabled(evdev->idle_src, SD_EVENT_OFF);
309 static int idev_evdev_resume(idev_evdev *evdev, int dev_fd) {
310 idev_element *e = &evdev->element;
311 _cleanup_close_ int fd = dev_fd;
314 if (fd < 0 || evdev->fd == fd) {
316 idev_evdev_enable(evdev);
320 idev_evdev_pause(evdev, true);
321 log_debug("idev-evdev: %s/%s: resume", e->session->name, e->name);
323 r = fd_nonblock(fd, true);
327 r = fd_cloexec(fd, true);
331 flags = fcntl(fd, F_GETFL, 0);
336 if (flags == O_WRONLY)
339 evdev->element.readable = true;
340 evdev->element.writable = !(flags & O_RDONLY);
343 * TODO: We *MUST* re-sync the device so we get a delta of the changed
344 * state while we didn't read events from the device. This works just
345 * fine with libevdev_change_fd(), however, libevdev_new_from_fd() (or
346 * libevdev_set_fd()) don't pass us events for the initial device
347 * state. So even if we force a re-sync, we will not get the delta for
348 * the initial device state.
349 * We really need to fix libevdev to support that!
352 r = libevdev_change_fd(evdev->evdev, fd);
354 r = libevdev_new_from_fd(fd, &evdev->evdev);
359 r = sd_event_add_io(e->session->context->event,
362 EPOLLHUP | EPOLLERR | EPOLLIN,
368 r = sd_event_add_defer(e->session->context->event,
373 evdev->fd_src = sd_event_source_unref(evdev->fd_src);
377 sd_event_source_set_enabled(evdev->fd_src, SD_EVENT_OFF);
378 sd_event_source_set_enabled(evdev->idle_src, SD_EVENT_OFF);
380 evdev->unsync = true;
384 idev_evdev_enable(evdev);
388 static void idev_evdev_pause(idev_evdev *evdev, bool release) {
389 idev_element *e = &evdev->element;
394 log_debug("idev-evdev: %s/%s: pause", e->session->name, e->name);
396 idev_evdev_disable(evdev);
398 evdev->idle_src = sd_event_source_unref(evdev->idle_src);
399 evdev->fd_src = sd_event_source_unref(evdev->fd_src);
400 evdev->fd = safe_close(evdev->fd);
405 * Unmanaged Evdev Element
406 * The unmanaged evdev element opens the evdev node for a given input device
407 * directly (/dev/input/eventX) and thus needs sufficient privileges. It opens
408 * the device only if we really require it and releases it as soon as we're
409 * disabled or closed.
410 * The unmanaged element can be used in all situations where you have direct
411 * access to input device nodes. Unlike managed evdev elements, it can be used
412 * outside of user sessions and in emergency situations where logind is not
416 static void unmanaged_evdev_resume(idev_element *e) {
417 unmanaged_evdev *eu = unmanaged_evdev_from_element(e);
421 * Unmanaged devices can be acquired on-demand. Therefore, don't
422 * acquire it unless someone opened the device *and* we're enabled.
424 if (e->n_open < 1 || !e->enabled)
429 fd = open(eu->devnode, O_RDWR | O_CLOEXEC | O_NOCTTY | O_NONBLOCK);
431 if (errno != EACCES && errno != EPERM) {
432 log_debug("idev-evdev: %s/%s: cannot open node %s: %m",
433 e->session->name, e->name, eu->devnode);
437 fd = open(eu->devnode, O_RDONLY | O_CLOEXEC | O_NOCTTY | O_NONBLOCK);
439 log_debug("idev-evdev: %s/%s: cannot open node %s: %m",
440 e->session->name, e->name, eu->devnode);
452 r = idev_evdev_resume(&eu->evdev, fd);
454 log_debug("idev-evdev: %s/%s: cannot resume: %s",
455 e->session->name, e->name, strerror(-r));
458 static void unmanaged_evdev_pause(idev_element *e) {
459 unmanaged_evdev *eu = unmanaged_evdev_from_element(e);
462 * Release the device if the device is disabled or there is no-one who
463 * opened it. This guarantees we stay only available if we're opened
467 idev_evdev_pause(&eu->evdev, true);
470 static int unmanaged_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {
471 _cleanup_(idev_element_freep) idev_element *e = NULL;
472 char name[IDEV_EVDEV_NAME_MAX];
478 assert_return(s, -EINVAL);
479 assert_return(ud, -EINVAL);
481 devnode = udev_device_get_devnode(ud);
482 devnum = udev_device_get_devnum(ud);
483 if (!devnode || devnum == 0)
486 idev_evdev_name(name, devnum);
488 eu = new0(unmanaged_evdev, 1);
492 e = &eu->evdev.element;
493 eu->evdev = IDEV_EVDEV_INIT(&unmanaged_evdev_vtable, s);
495 eu->devnode = strdup(devnode);
499 r = idev_element_add(e, name);
509 static void unmanaged_evdev_free(idev_element *e) {
510 unmanaged_evdev *eu = unmanaged_evdev_from_element(e);
512 idev_evdev_destroy(&eu->evdev);
517 static const idev_element_vtable unmanaged_evdev_vtable = {
518 .free = unmanaged_evdev_free,
519 .enable = unmanaged_evdev_resume,
520 .disable = unmanaged_evdev_pause,
521 .open = unmanaged_evdev_resume,
522 .close = unmanaged_evdev_pause,
526 * Managed Evdev Element
527 * The managed evdev element uses systemd-logind to acquire evdev devices. This
528 * means, we do not open the device node /dev/input/eventX directly. Instead,
529 * logind passes us a file-descriptor whenever our session is activated. Thus,
530 * we don't need access to the device node directly.
531 * Furthermore, whenever the session is put asleep, logind revokes the
532 * file-descriptor so we loose access to the device.
533 * Managed evdev elements should be preferred over unmanaged elements whenever
534 * you run inside a user session with exclusive device access.
537 static int managed_evdev_take_device_fn(sd_bus *bus,
538 sd_bus_message *reply,
540 sd_bus_error *ret_error) {
541 managed_evdev *em = userdata;
542 idev_element *e = &em->evdev.element;
543 idev_session *s = e->session;
546 em->slot_take_device = sd_bus_slot_unref(em->slot_take_device);
548 if (sd_bus_message_is_method_error(reply, NULL)) {
549 const sd_bus_error *error = sd_bus_message_get_error(reply);
551 log_debug("idev-evdev: %s/%s: TakeDevice failed: %s: %s",
552 s->name, e->name, error->name, error->message);
558 r = sd_bus_message_read(reply, "hb", &fd, &paused);
560 log_debug("idev-evdev: %s/%s: erroneous TakeDevice reply", s->name, e->name);
564 /* If the device is paused, ignore it; we will get the next fd via
565 * ResumeDevice signals. */
569 fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
571 log_debug("idev-evdev: %s/%s: cannot duplicate evdev fd: %m", s->name, e->name);
575 r = idev_evdev_resume(&em->evdev, fd);
577 log_debug("idev-evdev: %s/%s: cannot resume: %s",
578 s->name, e->name, strerror(-r));
583 static void managed_evdev_resume(idev_element *e) {
584 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
585 managed_evdev *em = managed_evdev_from_element(e);
586 idev_session *s = e->session;
587 idev_context *c = s->context;
591 * Acquiring managed devices is heavy, so do it only once we're
592 * enabled *and* opened by someone.
594 if (e->n_open < 1 || !e->enabled)
597 /* bail out if already pending */
601 r = sd_bus_message_new_method_call(c->sysbus,
603 "org.freedesktop.login1",
605 "org.freedesktop.login1.Session",
610 r = sd_bus_message_append(m, "uu", major(em->devnum), minor(em->devnum));
614 r = sd_bus_call_async(c->sysbus,
615 &em->slot_take_device,
617 managed_evdev_take_device_fn,
623 em->requested = true;
627 log_debug("idev-evdev: %s/%s: cannot send TakeDevice request: %s",
628 s->name, e->name, strerror(-r));
631 static void managed_evdev_pause(idev_element *e) {
632 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
633 managed_evdev *em = managed_evdev_from_element(e);
634 idev_session *s = e->session;
635 idev_context *c = s->context;
639 * Releasing managed devices is heavy. Once acquired, we get
640 * notifications for sleep/wake-up events, so there's no reason to
641 * release it if disabled but opened. However, if a device is closed,
642 * we release it immediately as we don't care for sleep/wake-up events
643 * then (even if we're actually enabled).
646 idev_evdev_pause(&em->evdev, false);
648 if (e->n_open > 0 || !em->requested)
652 * If TakeDevice() is pending or was successful, make sure to
653 * release the device again. We don't care for return-values,
654 * so send it without waiting or callbacks.
655 * If a failed TakeDevice() is pending, but someone else took
656 * the device on the same bus-connection, we might incorrectly
657 * release their device. This is an unlikely race, though.
658 * Furthermore, you really shouldn't have two users of the
659 * controller-API on the same session, on the same devices, *AND* on
660 * the same bus-connection. So we don't care for that race..
663 idev_evdev_pause(&em->evdev, true);
664 em->requested = false;
666 if (!em->acquired && !em->slot_take_device)
669 em->slot_take_device = sd_bus_slot_unref(em->slot_take_device);
670 em->acquired = false;
672 r = sd_bus_message_new_method_call(c->sysbus,
674 "org.freedesktop.login1",
676 "org.freedesktop.login1.Session",
679 r = sd_bus_message_append(m, "uu", major(em->devnum), minor(em->devnum));
681 r = sd_bus_send(c->sysbus, m, NULL);
684 if (r < 0 && r != -ENOTCONN)
685 log_debug("idev-evdev: %s/%s: cannot send ReleaseDevice: %s",
686 s->name, e->name, strerror(-r));
689 static int managed_evdev_pause_device_fn(sd_bus *bus,
690 sd_bus_message *signal,
692 sd_bus_error *ret_error) {
693 managed_evdev *em = userdata;
694 idev_element *e = &em->evdev.element;
695 idev_session *s = e->session;
696 idev_context *c = s->context;
697 uint32_t major, minor;
702 * We get PauseDevice() signals from logind whenever a device we
703 * requested was, or is about to be, paused. Arguments are major/minor
704 * number of the device and the mode of the operation.
705 * In case the event is not about our device, we ignore it. Otherwise,
706 * we treat it as asynchronous access-revocation (as if we got HUP on
707 * the device fd). Note that we might have already treated the HUP
708 * event via EPOLLHUP, whichever comes first.
710 * @mode can be one of the following:
711 * "pause": The device is about to be paused. We must react
712 * immediately and respond with PauseDeviceComplete(). Once
713 * we replied, logind will pause the device. Note that
714 * logind might apply any kind of timeout and force pause
715 * the device if we don't respond in a timely manner. In
716 * this case, we will receive a second PauseDevice event
717 * with @mode set to "force" (or similar).
718 * "force": The device was disabled forecfully by logind. Access is
719 * already revoked. This is just an asynchronous
720 * notification so we can put the device asleep (in case
721 * we didn't already notice the access revocation).
722 * "gone": This is like "force" but is sent if the device was
723 * paused due to a device-removal event.
725 * We always handle PauseDevice signals as "force" as we properly
726 * support asynchronous access revocation, anyway. But in case logind
727 * sent mode "pause", we also call PauseDeviceComplete() to immediately
728 * acknowledge the request.
731 r = sd_bus_message_read(signal, "uus", &major, &minor, &mode);
733 log_debug("idev-evdev: %s/%s: erroneous PauseDevice signal",
738 /* not our device? */
739 if (makedev(major, minor) != em->devnum)
742 idev_evdev_pause(&em->evdev, true);
744 if (streq(mode, "pause")) {
745 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
748 * Sending PauseDeviceComplete() is racy if logind triggers the
749 * timeout. That is, if we take too long and logind pauses the
750 * device by sending a forced PauseDevice, our
751 * PauseDeviceComplete call will be stray. That's fine, though.
752 * logind ignores such stray calls. Only if logind also sent a
753 * further PauseDevice() signal, it might match our call
754 * incorrectly to the newer PauseDevice(). That's fine, too, as
755 * we handle that event asynchronously, anyway. Therefore,
756 * whatever happens, we're fine. Yay!
759 r = sd_bus_message_new_method_call(c->sysbus,
761 "org.freedesktop.login1",
763 "org.freedesktop.login1.Session",
764 "PauseDeviceComplete");
766 r = sd_bus_message_append(m, "uu", major, minor);
768 r = sd_bus_send(c->sysbus, m, NULL);
772 log_debug("idev-evdev: %s/%s: cannot send PauseDeviceComplete: %s",
773 s->name, e->name, strerror(-r));
779 static int managed_evdev_resume_device_fn(sd_bus *bus,
780 sd_bus_message *signal,
782 sd_bus_error *ret_error) {
783 managed_evdev *em = userdata;
784 idev_element *e = &em->evdev.element;
785 idev_session *s = e->session;
786 uint32_t major, minor;
790 * We get ResumeDevice signals whenever logind resumed a previously
791 * paused device. The arguments contain the major/minor number of the
792 * related device and a new file-descriptor for the freshly opened
794 * If the signal is not about our device, we simply ignore it.
795 * Otherwise, we take the file-descriptor and immediately resume the
799 r = sd_bus_message_read(signal, "uuh", &major, &minor, &fd);
801 log_debug("idev-evdev: %s/%s: erroneous ResumeDevice signal",
806 /* not our device? */
807 if (makedev(major, minor) != em->devnum)
810 fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
812 log_debug("idev-evdev: %s/%s: cannot duplicate evdev fd: %m",
817 r = idev_evdev_resume(&em->evdev, fd);
819 log_debug("idev-evdev: %s/%s: cannot resume: %s",
820 s->name, e->name, strerror(-r));
825 static int managed_evdev_setup_bus(managed_evdev *em) {
826 idev_element *e = &em->evdev.element;
827 idev_session *s = e->session;
828 idev_context *c = s->context;
829 _cleanup_free_ char *match = NULL;
832 match = strjoin("type='signal',"
833 "sender='org.freedesktop.login1',"
834 "interface='org.freedesktop.login1.Session',"
835 "member='PauseDevice',"
836 "path='", s->path, "'",
841 r = sd_bus_add_match(c->sysbus,
842 &em->slot_pause_device,
844 managed_evdev_pause_device_fn,
850 match = strjoin("type='signal',"
851 "sender='org.freedesktop.login1',"
852 "interface='org.freedesktop.login1.Session',"
853 "member='ResumeDevice',"
854 "path='", s->path, "'",
859 r = sd_bus_add_match(c->sysbus,
860 &em->slot_resume_device,
862 managed_evdev_resume_device_fn,
870 static int managed_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {
871 _cleanup_(idev_element_freep) idev_element *e = NULL;
872 char name[IDEV_EVDEV_NAME_MAX];
877 assert_return(s, -EINVAL);
878 assert_return(s->managed, -EINVAL);
879 assert_return(s->context->sysbus, -EINVAL);
880 assert_return(ud, -EINVAL);
882 devnum = udev_device_get_devnum(ud);
886 idev_evdev_name(name, devnum);
888 em = new0(managed_evdev, 1);
892 e = &em->evdev.element;
893 em->evdev = IDEV_EVDEV_INIT(&managed_evdev_vtable, s);
896 r = managed_evdev_setup_bus(em);
900 r = idev_element_add(e, name);
910 static void managed_evdev_free(idev_element *e) {
911 managed_evdev *em = managed_evdev_from_element(e);
913 em->slot_resume_device = sd_bus_slot_unref(em->slot_resume_device);
914 em->slot_pause_device = sd_bus_slot_unref(em->slot_pause_device);
915 idev_evdev_destroy(&em->evdev);
919 static const idev_element_vtable managed_evdev_vtable = {
920 .free = managed_evdev_free,
921 .enable = managed_evdev_resume,
922 .disable = managed_evdev_pause,
923 .open = managed_evdev_resume,
924 .close = managed_evdev_pause,
928 * Generic Constructor
929 * Instead of relying on the caller to choose between managed and unmanaged
930 * evdev devices, the idev_evdev_new() constructor does that for you (by
931 * looking at s->managed).
934 bool idev_is_evdev(idev_element *e) {
935 return e && (e->vtable == &unmanaged_evdev_vtable ||
936 e->vtable == &managed_evdev_vtable);
939 idev_element *idev_find_evdev(idev_session *s, dev_t devnum) {
940 char name[IDEV_EVDEV_NAME_MAX];
942 assert_return(s, NULL);
943 assert_return(devnum != 0, NULL);
945 idev_evdev_name(name, devnum);
946 return idev_find_element(s, name);
949 int idev_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {
950 assert_return(s, -EINVAL);
951 assert_return(ud, -EINVAL);
953 return s->managed ? managed_evdev_new(out, s, ud) : unmanaged_evdev_new(out, s, ud);