src/login/logind-device.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <string.h>
   4
   5 #include "alloc-util.h"
   6 #include "hashmap.h"
   7 #include "logind.h"
   8 #include "logind-device.h"
   9 #include "logind-seat.h"
  10 #include "logind-seat-dbus.h"
  11 #include "logind-session-device.h"
  12
  13 Device* device_new(Manager *m, const char *sysfs, bool master) {
  14         Device *d;
  15
  16         assert(m);
  17         assert(sysfs);
  18
  19         d = new0(Device, 1);
  20         if (!d)
  21                 return NULL;
  22
  23         d->sysfs = strdup(sysfs);
  24         if (!d->sysfs)
  25                 return mfree(d);
  26
  27         if (hashmap_put(m->devices, d->sysfs, d) < 0) {
  28                 free(d->sysfs);
  29                 return mfree(d);
  30         }
  31
  32         d->manager = m;
  33         d->master = master;
  34         dual_timestamp_now(&d->timestamp);
  35
  36         return d;
  37 }
  38
  39 static void device_detach(Device *d) {
  40         Seat *s;
  41         SessionDevice *sd;
  42
  43         assert(d);
  44
  45         if (!d->seat)
  46                 return;
  47
  48         while ((sd = d->session_devices))
  49                 session_device_free(sd);
  50
  51         s = d->seat;
  52         LIST_REMOVE(devices, d->seat->devices, d);
  53         d->seat = NULL;
  54
  55         if (!seat_has_master_device(s)) {
  56                 seat_add_to_gc_queue(s);
  57                 seat_send_changed(s, "CanGraphical");
  58         }
  59 }
  60
  61 void device_free(Device *d) {
  62         assert(d);
  63
  64         device_detach(d);
  65
  66         hashmap_remove(d->manager->devices, d->sysfs);
  67
  68         free(d->sysfs);
  69         free(d);
  70 }
  71
  72 void device_attach(Device *d, Seat *s) {
  73         bool had_master;
  74
  75         assert(d);
  76         assert(s);
  77
  78         if (d->seat == s)
  79                 return;
  80
  81         if (d->seat)
  82                 device_detach(d);
  83
  84         d->seat = s;
  85         had_master = seat_has_master_device(s);
  86
  87         /* We keep the device list sorted by the "master" flag. That is, master
  88          * devices are at the front, other devices at the tail. As there is no
  89          * way to easily add devices at the list-tail, we need to iterate the
  90          * list to find the first non-master device when adding non-master
  91          * devices. We assume there is only a few (normally 1) master devices
  92          * per seat, so we iterate only a few times. */
  93
  94         if (d->master || !s->devices)
  95                 LIST_PREPEND(devices, s->devices, d);
  96         else
  97                 LIST_FOREACH(devices, i, s->devices) {
  98                         if (!i->devices_next || !i->master) {
  99                                 LIST_INSERT_AFTER(devices, s->devices, i, d);
 100                                 break;
 101                         }
 102                 }
 103
 104         if (!had_master && d->master && s->started) {
 105                 seat_save(s);
 106                 seat_send_changed(s, "CanGraphical");
 107         }
 108 }