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 */
54 struct unmanaged_evdev {
59 struct managed_evdev {
63 sd_bus_slot *slot_pause_device;
64 sd_bus_slot *slot_resume_device;
65 sd_bus_slot *slot_take_device;
67 bool requested : 1; /* TakeDevice() was sent */
68 bool acquired : 1; /* TakeDevice() was successful */
71 #define idev_evdev_from_element(_e) container_of((_e), idev_evdev, element)
72 #define unmanaged_evdev_from_element(_e) \
73 container_of(idev_evdev_from_element(_e), unmanaged_evdev, evdev)
74 #define managed_evdev_from_element(_e) \
75 container_of(idev_evdev_from_element(_e), managed_evdev, evdev)
77 #define IDEV_EVDEV_INIT(_vtable, _session) ((idev_evdev){ \
78 .element = IDEV_ELEMENT_INIT((_vtable), (_session)), \
82 #define IDEV_EVDEV_NAME_MAX (8 + DECIMAL_STR_MAX(unsigned) * 2)
84 static const idev_element_vtable unmanaged_evdev_vtable;
85 static const idev_element_vtable managed_evdev_vtable;
87 static int idev_evdev_resume(idev_evdev *evdev, int dev_fd);
88 static void idev_evdev_pause(idev_evdev *evdev, bool release);
91 * Virtual Evdev Element
92 * The virtual evdev element is the base class of all other evdev elements. It
93 * uses libevdev to access the kernel evdev API. It supports asynchronous
94 * access revocation, re-syncing if events got dropped and more.
95 * This element cannot be used by itself. There must be a wrapper around it
96 * which opens a file-descriptor and passes it to the virtual evdev element.
99 static void idev_evdev_name(char *out, dev_t devnum) {
100 /* @out must be at least of size IDEV_EVDEV_NAME_MAX */
101 sprintf(out, "evdev/%u:%u", major(devnum), minor(devnum));
104 static int idev_evdev_raise(idev_evdev *evdev, struct input_event *event) {
106 .type = IDEV_DATA_EVDEV,
107 .resync = evdev->resync,
113 return idev_element_feed(&evdev->element, &data);
116 static void idev_evdev_hup(idev_evdev *evdev) {
118 * On HUP, we close the current fd via idev_evdev_pause(). This drops
119 * the event-sources from the main-loop and effectively puts the
120 * element asleep. If the HUP is part of a hotplug-event, a following
121 * udev-notification will destroy the element. Otherwise, the HUP is
122 * either result of access-revokation or a serious error.
123 * For unmanaged devices, we should never receive HUP (except for
124 * unplug-events). But if we do, something went seriously wrong and we
125 * shouldn't try to be clever.
126 * Instead, we simply stay asleep and wait for the device to be
127 * disabled and then re-enabled (or closed and re-opened). This will
128 * re-open the device node and restart the device.
129 * For managed devices, a HUP usually means our device-access was
130 * revoked. In that case, we simply put the device asleep and wait for
131 * logind to notify us once the device is alive again. logind also
132 * passes us a new fd. Hence, we don't have to re-enable the device.
134 * Long story short: The only thing we have to do here, is close() the
135 * file-descriptor and remove it from the main-loop. Everything else is
136 * handled via additional events we receive.
139 idev_evdev_pause(evdev, true);
142 static int idev_evdev_io(idev_evdev *evdev) {
143 idev_element *e = &evdev->element;
144 struct input_event ev;
149 * Read input-events via libevdev until the input-queue is drained. In
150 * case we're disabled, don't do anything. The input-queue might
151 * overflow, but we don't care as we have to resync after wake-up,
153 * TODO: libevdev should give us a hint how many events to read. We
154 * really want to avoid starvation, so we shouldn't read forever in
155 * case we cannot keep up with the kernel.
156 * TODO: Make sure libevdev always reports SYN_DROPPED to us, regardless
157 * whether any event was synced afterwards.
158 * TODO: Forward SYN_DROPPED to attached devices.
161 flags = LIBEVDEV_READ_FLAG_NORMAL;
164 /* immediately resync, even if in sync right now */
165 evdev->unsync = false;
166 evdev->resync = false;
167 flags = LIBEVDEV_READ_FLAG_NORMAL;
168 r = libevdev_next_event(evdev->evdev, flags | LIBEVDEV_READ_FLAG_FORCE_SYNC, &ev);
169 if (r < 0 && r != -EAGAIN) {
172 } else if (r != LIBEVDEV_READ_STATUS_SYNC) {
173 log_debug("idev-evdev: %s/%s: cannot force resync: %d",
174 e->session->name, e->name, r);
177 r = libevdev_next_event(evdev->evdev, flags, &ev);
180 if (evdev->resync && r == -EAGAIN) {
182 evdev->resync = false;
183 flags = LIBEVDEV_READ_FLAG_NORMAL;
184 } else if (r == -EAGAIN) {
185 /* no data available */
190 } else if (r == LIBEVDEV_READ_STATUS_SYNC) {
193 r = idev_evdev_raise(evdev, &ev);
200 evdev->resync = true;
201 flags = LIBEVDEV_READ_FLAG_SYNC;
205 r = idev_evdev_raise(evdev, &ev);
214 log_debug("idev-evdev: %s/%s: error on data event: %s",
215 e->session->name, e->name, strerror(-error));
219 idev_evdev_hup(evdev);
220 return 0; /* idev_evdev_hup() handles the error so discard it */
223 static int idev_evdev_event_fn(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
224 idev_evdev *evdev = userdata;
226 /* fetch data as long as EPOLLIN is signalled */
227 if (revents & EPOLLIN)
228 return idev_evdev_io(evdev);
230 if (revents & (EPOLLHUP | EPOLLERR))
231 idev_evdev_hup(evdev);
236 static int idev_evdev_idle_fn(sd_event_source *s, void *userdata) {
237 idev_evdev *evdev = userdata;
240 * The idle-event is raised whenever we have to re-sync the libevdev
241 * state from the kernel. We simply call into idev_evdev_io() which
242 * flushes the state and re-syncs it if @unsync is set.
243 * State has to be synced whenever our view of the kernel device is
244 * out of date. This is the case when we open the device, if the
245 * kernel's receive buffer overflows, or on other exceptional
246 * situations. Events during re-syncs must be forwarded to the upper
247 * layers so they can update their view of the device. However, such
248 * events must only be handled passively, as they might be out-of-order
249 * and/or re-ordered. Therefore, we mark them as 'sync' events.
255 return idev_evdev_io(evdev);
258 static void idev_evdev_destroy(idev_evdev *evdev) {
260 assert(evdev->fd < 0);
262 libevdev_free(evdev->evdev);
266 static void idev_evdev_enable(idev_evdev *evdev) {
268 assert(evdev->fd_src);
269 assert(evdev->idle_src);
271 sd_event_source_set_enabled(evdev->fd_src, SD_EVENT_ON);
272 sd_event_source_set_enabled(evdev->idle_src, SD_EVENT_ONESHOT);
275 static void idev_evdev_disable(idev_evdev *evdev) {
277 assert(evdev->fd_src);
278 assert(evdev->idle_src);
280 sd_event_source_set_enabled(evdev->fd_src, SD_EVENT_OFF);
281 sd_event_source_set_enabled(evdev->idle_src, SD_EVENT_OFF);
284 static int idev_evdev_resume(idev_evdev *evdev, int dev_fd) {
285 idev_element *e = &evdev->element;
286 _cleanup_close_ int fd = dev_fd;
289 if (fd < 0 || evdev->fd == fd) {
291 if (evdev->fd >= 0 && e->n_open > 0 && e->enabled)
292 idev_evdev_enable(evdev);
297 idev_evdev_pause(evdev, true);
298 log_debug("idev-evdev: %s/%s: resume", e->session->name, e->name);
300 r = fd_nonblock(fd, true);
304 r = fd_cloexec(fd, true);
308 flags = fcntl(fd, F_GETFL, 0);
313 if (flags == O_WRONLY)
316 evdev->element.readable = true;
317 evdev->element.writable = !(flags & O_RDONLY);
320 * TODO: We *MUST* re-sync the device so we get a delta of the changed
321 * state while we didn't read events from the device. This works just
322 * fine with libevdev_change_fd(), however, libevdev_new_from_fd() (or
323 * libevdev_set_fd()) don't pass us events for the initial device
324 * state. So even if we force a re-sync, we will not get the delta for
325 * the initial device state.
326 * We really need to fix libevdev to support that!
329 r = libevdev_change_fd(evdev->evdev, fd);
331 r = libevdev_new_from_fd(fd, &evdev->evdev);
336 r = sd_event_add_io(e->session->context->event,
339 EPOLLHUP | EPOLLERR | EPOLLIN,
345 r = sd_event_add_defer(e->session->context->event,
350 evdev->fd_src = sd_event_source_unref(evdev->fd_src);
354 if (e->n_open < 1 || !e->enabled) {
355 sd_event_source_set_enabled(evdev->fd_src, SD_EVENT_OFF);
356 sd_event_source_set_enabled(evdev->idle_src, SD_EVENT_OFF);
359 evdev->unsync = true;
366 static void idev_evdev_pause(idev_evdev *evdev, bool release) {
367 idev_element *e = &evdev->element;
372 log_debug("idev-evdev: %s/%s: pause", e->session->name, e->name);
375 evdev->idle_src = sd_event_source_unref(evdev->idle_src);
376 evdev->fd_src = sd_event_source_unref(evdev->fd_src);
377 evdev->fd = safe_close(evdev->fd);
379 idev_evdev_disable(evdev);
384 * Unmanaged Evdev Element
385 * The unmanaged evdev element opens the evdev node for a given input device
386 * directly (/dev/input/eventX) and thus needs sufficient privileges. It opens
387 * the device only if we really require it and releases it as soon as we're
388 * disabled or closed.
389 * The unmanaged element can be used in all situations where you have direct
390 * access to input device nodes. Unlike managed evdev elements, it can be used
391 * outside of user sessions and in emergency situations where logind is not
395 static void unmanaged_evdev_resume(idev_element *e) {
396 unmanaged_evdev *eu = unmanaged_evdev_from_element(e);
400 * Unmanaged devices can be acquired on-demand. Therefore, don't
401 * acquire it unless someone opened the device *and* we're enabled.
403 if (e->n_open < 1 || !e->enabled)
408 fd = open(eu->devnode, O_RDWR | O_CLOEXEC | O_NOCTTY | O_NONBLOCK);
410 if (errno != EACCES && errno != EPERM) {
411 log_debug("idev-evdev: %s/%s: cannot open node %s: %m",
412 e->session->name, e->name, eu->devnode);
416 fd = open(eu->devnode, O_RDONLY | O_CLOEXEC | O_NOCTTY | O_NONBLOCK);
418 log_debug("idev-evdev: %s/%s: cannot open node %s: %m",
419 e->session->name, e->name, eu->devnode);
431 r = idev_evdev_resume(&eu->evdev, fd);
433 log_debug("idev-evdev: %s/%s: cannot resume: %s",
434 e->session->name, e->name, strerror(-r));
437 static void unmanaged_evdev_pause(idev_element *e) {
438 unmanaged_evdev *eu = unmanaged_evdev_from_element(e);
441 * Release the device if the device is disabled or there is no-one who
442 * opened it. This guarantees we stay only available if we're opened
446 idev_evdev_pause(&eu->evdev, true);
449 static int unmanaged_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {
450 _cleanup_(idev_element_freep) idev_element *e = NULL;
451 char name[IDEV_EVDEV_NAME_MAX];
457 assert_return(s, -EINVAL);
458 assert_return(ud, -EINVAL);
460 devnode = udev_device_get_devnode(ud);
461 devnum = udev_device_get_devnum(ud);
462 if (!devnode || devnum == 0)
465 idev_evdev_name(name, devnum);
467 eu = new0(unmanaged_evdev, 1);
471 e = &eu->evdev.element;
472 eu->evdev = IDEV_EVDEV_INIT(&unmanaged_evdev_vtable, s);
474 eu->devnode = strdup(devnode);
478 r = idev_element_add(e, name);
488 static void unmanaged_evdev_free(idev_element *e) {
489 unmanaged_evdev *eu = unmanaged_evdev_from_element(e);
491 idev_evdev_destroy(&eu->evdev);
496 static const idev_element_vtable unmanaged_evdev_vtable = {
497 .free = unmanaged_evdev_free,
498 .enable = unmanaged_evdev_resume,
499 .disable = unmanaged_evdev_pause,
500 .open = unmanaged_evdev_resume,
501 .close = unmanaged_evdev_pause,
505 * Managed Evdev Element
506 * The managed evdev element uses systemd-logind to acquire evdev devices. This
507 * means, we do not open the device node /dev/input/eventX directly. Instead,
508 * logind passes us a file-descriptor whenever our session is activated. Thus,
509 * we don't need access to the device node directly.
510 * Furthermore, whenever the session is put asleep, logind revokes the
511 * file-descriptor so we loose access to the device.
512 * Managed evdev elements should be preferred over unmanaged elements whenever
513 * you run inside a user session with exclusive device access.
516 static int managed_evdev_take_device_fn(sd_bus *bus,
517 sd_bus_message *reply,
519 sd_bus_error *ret_error) {
520 managed_evdev *em = userdata;
521 idev_element *e = &em->evdev.element;
522 idev_session *s = e->session;
525 em->slot_take_device = sd_bus_slot_unref(em->slot_take_device);
527 if (sd_bus_message_is_method_error(reply, NULL)) {
528 const sd_bus_error *error = sd_bus_message_get_error(reply);
530 log_debug("idev-evdev: %s/%s: TakeDevice failed: %s: %s",
531 s->name, e->name, error->name, error->message);
537 r = sd_bus_message_read(reply, "hb", &fd, &paused);
539 log_debug("idev-evdev: %s/%s: erroneous TakeDevice reply", s->name, e->name);
543 /* If the device is paused, ignore it; we will get the next fd via
544 * ResumeDevice signals. */
548 fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
550 log_debug("idev-evdev: %s/%s: cannot duplicate evdev fd: %m", s->name, e->name);
554 r = idev_evdev_resume(&em->evdev, fd);
556 log_debug("idev-evdev: %s/%s: cannot resume: %s",
557 s->name, e->name, strerror(-r));
562 static void managed_evdev_resume(idev_element *e) {
563 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
564 managed_evdev *em = managed_evdev_from_element(e);
565 idev_session *s = e->session;
566 idev_context *c = s->context;
570 * Acquiring managed devices is heavy, so do it only once we're
571 * enabled *and* opened by someone.
573 if (e->n_open < 1 || !e->enabled)
576 /* bail out if already pending */
580 r = sd_bus_message_new_method_call(c->sysbus,
582 "org.freedesktop.login1",
584 "org.freedesktop.login1.Session",
589 r = sd_bus_message_append(m, "uu", major(em->devnum), minor(em->devnum));
593 r = sd_bus_call_async(c->sysbus,
594 &em->slot_take_device,
596 managed_evdev_take_device_fn,
602 em->requested = true;
606 log_debug("idev-evdev: %s/%s: cannot send TakeDevice request: %s",
607 s->name, e->name, strerror(-r));
610 static void managed_evdev_pause(idev_element *e) {
611 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
612 managed_evdev *em = managed_evdev_from_element(e);
613 idev_session *s = e->session;
614 idev_context *c = s->context;
618 * Releasing managed devices is heavy. Once acquired, we get
619 * notifications for sleep/wake-up events, so there's no reason to
620 * release it if disabled but opened. However, if a device is closed,
621 * we release it immediately as we don't care for sleep/wake-up events
622 * then (even if we're actually enabled).
625 idev_evdev_pause(&em->evdev, false);
627 if (e->n_open > 0 || !em->requested)
631 * If TakeDevice() is pending or was successful, make sure to
632 * release the device again. We don't care for return-values,
633 * so send it without waiting or callbacks.
634 * If a failed TakeDevice() is pending, but someone else took
635 * the device on the same bus-connection, we might incorrectly
636 * release their device. This is an unlikely race, though.
637 * Furthermore, you really shouldn't have two users of the
638 * controller-API on the same session, on the same devices, *AND* on
639 * the same bus-connection. So we don't care for that race..
642 idev_evdev_pause(&em->evdev, true);
643 em->requested = false;
645 if (!em->acquired && !em->slot_take_device)
648 em->slot_take_device = sd_bus_slot_unref(em->slot_take_device);
649 em->acquired = false;
651 r = sd_bus_message_new_method_call(c->sysbus,
653 "org.freedesktop.login1",
655 "org.freedesktop.login1.Session",
658 r = sd_bus_message_append(m, "uu", major(em->devnum), minor(em->devnum));
660 r = sd_bus_send(c->sysbus, m, NULL);
663 if (r < 0 && r != -ENOTCONN)
664 log_debug("idev-evdev: %s/%s: cannot send ReleaseDevice: %s",
665 s->name, e->name, strerror(-r));
668 static int managed_evdev_pause_device_fn(sd_bus *bus,
669 sd_bus_message *signal,
671 sd_bus_error *ret_error) {
672 managed_evdev *em = userdata;
673 idev_element *e = &em->evdev.element;
674 idev_session *s = e->session;
675 idev_context *c = s->context;
676 uint32_t major, minor;
681 * We get PauseDevice() signals from logind whenever a device we
682 * requested was, or is about to be, paused. Arguments are major/minor
683 * number of the device and the mode of the operation.
684 * In case the event is not about our device, we ignore it. Otherwise,
685 * we treat it as asynchronous access-revocation (as if we got HUP on
686 * the device fd). Note that we might have already treated the HUP
687 * event via EPOLLHUP, whichever comes first.
689 * @mode can be one of the following:
690 * "pause": The device is about to be paused. We must react
691 * immediately and respond with PauseDeviceComplete(). Once
692 * we replied, logind will pause the device. Note that
693 * logind might apply any kind of timeout and force pause
694 * the device if we don't respond in a timely manner. In
695 * this case, we will receive a second PauseDevice event
696 * with @mode set to "force" (or similar).
697 * "force": The device was disabled forecfully by logind. Access is
698 * already revoked. This is just an asynchronous
699 * notification so we can put the device asleep (in case
700 * we didn't already notice the access revocation).
701 * "gone": This is like "force" but is sent if the device was
702 * paused due to a device-removal event.
704 * We always handle PauseDevice signals as "force" as we properly
705 * support asynchronous access revocation, anyway. But in case logind
706 * sent mode "pause", we also call PauseDeviceComplete() to immediately
707 * acknowledge the request.
710 r = sd_bus_message_read(signal, "uus", &major, &minor, &mode);
712 log_debug("idev-evdev: %s/%s: erroneous PauseDevice signal",
717 /* not our device? */
718 if (makedev(major, minor) != em->devnum)
721 idev_evdev_pause(&em->evdev, true);
723 if (streq(mode, "pause")) {
724 _cleanup_bus_message_unref_ sd_bus_message *m = NULL;
727 * Sending PauseDeviceComplete() is racy if logind triggers the
728 * timeout. That is, if we take too long and logind pauses the
729 * device by sending a forced PauseDevice, our
730 * PauseDeviceComplete call will be stray. That's fine, though.
731 * logind ignores such stray calls. Only if logind also sent a
732 * further PauseDevice() signal, it might match our call
733 * incorrectly to the newer PauseDevice(). That's fine, too, as
734 * we handle that event asynchronously, anyway. Therefore,
735 * whatever happens, we're fine. Yay!
738 r = sd_bus_message_new_method_call(c->sysbus,
740 "org.freedesktop.login1",
742 "org.freedesktop.login1.Session",
743 "PauseDeviceComplete");
745 r = sd_bus_message_append(m, "uu", major, minor);
747 r = sd_bus_send(c->sysbus, m, NULL);
751 log_debug("idev-evdev: %s/%s: cannot send PauseDeviceComplete: %s",
752 s->name, e->name, strerror(-r));
758 static int managed_evdev_resume_device_fn(sd_bus *bus,
759 sd_bus_message *signal,
761 sd_bus_error *ret_error) {
762 managed_evdev *em = userdata;
763 idev_element *e = &em->evdev.element;
764 idev_session *s = e->session;
765 uint32_t major, minor;
769 * We get ResumeDevice signals whenever logind resumed a previously
770 * paused device. The arguments contain the major/minor number of the
771 * related device and a new file-descriptor for the freshly opened
773 * If the signal is not about our device, we simply ignore it.
774 * Otherwise, we take the file-descriptor and immediately resume the
778 r = sd_bus_message_read(signal, "uuh", &major, &minor, &fd);
780 log_debug("idev-evdev: %s/%s: erroneous ResumeDevice signal",
785 /* not our device? */
786 if (makedev(major, minor) != em->devnum)
789 fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
791 log_debug("idev-evdev: %s/%s: cannot duplicate evdev fd: %m",
796 r = idev_evdev_resume(&em->evdev, fd);
798 log_debug("idev-evdev: %s/%s: cannot resume: %s",
799 s->name, e->name, strerror(-r));
804 static int managed_evdev_setup_bus(managed_evdev *em) {
805 idev_element *e = &em->evdev.element;
806 idev_session *s = e->session;
807 idev_context *c = s->context;
808 _cleanup_free_ char *match = NULL;
811 match = strjoin("type='signal',"
812 "sender='org.freedesktop.login1',"
813 "interface='org.freedesktop.login1.Session',"
814 "member='PauseDevice',"
815 "path='", s->path, "'",
820 r = sd_bus_add_match(c->sysbus,
821 &em->slot_pause_device,
823 managed_evdev_pause_device_fn,
829 match = strjoin("type='signal',"
830 "sender='org.freedesktop.login1',"
831 "interface='org.freedesktop.login1.Session',"
832 "member='ResumeDevice',"
833 "path='", s->path, "'",
838 r = sd_bus_add_match(c->sysbus,
839 &em->slot_resume_device,
841 managed_evdev_resume_device_fn,
849 static int managed_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {
850 _cleanup_(idev_element_freep) idev_element *e = NULL;
851 char name[IDEV_EVDEV_NAME_MAX];
856 assert_return(s, -EINVAL);
857 assert_return(s->managed, -EINVAL);
858 assert_return(s->context->sysbus, -EINVAL);
859 assert_return(ud, -EINVAL);
861 devnum = udev_device_get_devnum(ud);
865 idev_evdev_name(name, devnum);
867 em = new0(managed_evdev, 1);
871 e = &em->evdev.element;
872 em->evdev = IDEV_EVDEV_INIT(&managed_evdev_vtable, s);
875 r = managed_evdev_setup_bus(em);
879 r = idev_element_add(e, name);
889 static void managed_evdev_free(idev_element *e) {
890 managed_evdev *em = managed_evdev_from_element(e);
892 em->slot_resume_device = sd_bus_slot_unref(em->slot_resume_device);
893 em->slot_pause_device = sd_bus_slot_unref(em->slot_pause_device);
894 idev_evdev_destroy(&em->evdev);
898 static const idev_element_vtable managed_evdev_vtable = {
899 .free = managed_evdev_free,
900 .enable = managed_evdev_resume,
901 .disable = managed_evdev_pause,
902 .open = managed_evdev_resume,
903 .close = managed_evdev_pause,
907 * Generic Constructor
908 * Instead of relying on the caller to choose between managed and unmanaged
909 * evdev devices, the idev_evdev_new() constructor does that for you (by
910 * looking at s->managed).
913 bool idev_is_evdev(idev_element *e) {
914 return e && (e->vtable == &unmanaged_evdev_vtable ||
915 e->vtable == &managed_evdev_vtable);
918 idev_element *idev_find_evdev(idev_session *s, dev_t devnum) {
919 char name[IDEV_EVDEV_NAME_MAX];
921 assert_return(s, NULL);
922 assert_return(devnum != 0, NULL);
924 idev_evdev_name(name, devnum);
925 return idev_find_element(s, name);
928 int idev_evdev_new(idev_element **out, idev_session *s, struct udev_device *ud) {
929 assert_return(s, -EINVAL);
930 assert_return(ud, -EINVAL);
932 return s->managed ? managed_evdev_new(out, s, ud) : unmanaged_evdev_new(out, s, ud);