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