src/login/logind-device.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <string.h>
   4
   5 #include "alloc-util.h"
   6 #include "logind-device.h"
   7 #include "logind-seat-dbus.h"
   8 #include "util.h"
   9
  10 Device* device_new(Manager *m, const char *sysfs, bool master) {
  11         Device *d;
  12
  13         assert(m);
  14         assert(sysfs);
  15
  16         d = new0(Device, 1);
  17         if (!d)
  18                 return NULL;
  19
  20         d->sysfs = strdup(sysfs);
  21         if (!d->sysfs)
  22                 return mfree(d);
  23
  24         if (hashmap_put(m->devices, d->sysfs, d) < 0) {
  25                 free(d->sysfs);
  26                 return mfree(d);
  27         }
  28
  29         d->manager = m;
  30         d->master = master;
  31         dual_timestamp_get(&d->timestamp);
  32
  33         return d;
  34 }
  35
  36 static void device_detach(Device *d) {
  37         Seat *s;
  38         SessionDevice *sd;
  39
  40         assert(d);
  41
  42         if (!d->seat)
  43                 return;
  44
  45         while ((sd = d->session_devices))
  46                 session_device_free(sd);
  47
  48         s = d->seat;
  49         LIST_REMOVE(devices, d->seat->devices, d);
  50         d->seat = NULL;
  51
  52         if (!seat_has_master_device(s)) {
  53                 seat_add_to_gc_queue(s);
  54                 seat_send_changed(s, "CanGraphical", NULL);
  55         }
  56 }
  57
  58 void device_free(Device *d) {
  59         assert(d);
  60
  61         device_detach(d);
  62
  63         hashmap_remove(d->manager->devices, d->sysfs);
  64
  65         free(d->sysfs);
  66         free(d);
  67 }
  68
  69 void device_attach(Device *d, Seat *s) {
  70         Device *i;
  71         bool had_master;
  72
  73         assert(d);
  74         assert(s);
  75
  76         if (d->seat == s)
  77                 return;
  78
  79         if (d->seat)
  80                 device_detach(d);
  81
  82         d->seat = s;
  83         had_master = seat_has_master_device(s);
  84
  85         /* We keep the device list sorted by the "master" flag. That is, master
  86          * devices are at the front, other devices at the tail. As there is no
  87          * way to easily add devices at the list-tail, we need to iterate the
  88          * list to find the first non-master device when adding non-master
  89          * devices. We assume there is only a few (normally 1) master devices
  90          * per seat, so we iterate only a few times. */
  91
  92         if (d->master || !s->devices)
  93                 LIST_PREPEND(devices, s->devices, d);
  94         else {
  95                 LIST_FOREACH(devices, i, s->devices) {
  96                         if (!i->devices_next || !i->master) {
  97                                 LIST_INSERT_AFTER(devices, s->devices, i, d);
  98                                 break;
  99                         }
 100                 }
 101         }
 102
 103         if (!had_master && d->master && s->started) {
 104                 seat_save(s);
 105                 seat_send_changed(s, "CanGraphical", NULL);
 106         }
 107 }