src/login/logind-device.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2011 Lennart Poettering
   4 ***/
   5
   6 #include <string.h>
   7
   8 #include "alloc-util.h"
   9 #include "logind-device.h"
  10 #include "util.h"
  11
  12 Device* device_new(Manager *m, const char *sysfs, bool master) {
  13         Device *d;
  14
  15         assert(m);
  16         assert(sysfs);
  17
  18         d = new0(Device, 1);
  19         if (!d)
  20                 return NULL;
  21
  22         d->sysfs = strdup(sysfs);
  23         if (!d->sysfs)
  24                 return mfree(d);
  25
  26         if (hashmap_put(m->devices, d->sysfs, d) < 0) {
  27                 free(d->sysfs);
  28                 return mfree(d);
  29         }
  30
  31         d->manager = m;
  32         d->master = master;
  33         dual_timestamp_get(&d->timestamp);
  34
  35         return d;
  36 }
  37
  38 static void device_detach(Device *d) {
  39         Seat *s;
  40         SessionDevice *sd;
  41
  42         assert(d);
  43
  44         if (!d->seat)
  45                 return;
  46
  47         while ((sd = d->session_devices))
  48                 session_device_free(sd);
  49
  50         s = d->seat;
  51         LIST_REMOVE(devices, d->seat->devices, d);
  52         d->seat = NULL;
  53
  54         if (!seat_has_master_device(s)) {
  55                 seat_add_to_gc_queue(s);
  56                 seat_send_changed(s, "CanGraphical", NULL);
  57         }
  58 }
  59
  60 void device_free(Device *d) {
  61         assert(d);
  62
  63         device_detach(d);
  64
  65         hashmap_remove(d->manager->devices, d->sysfs);
  66
  67         free(d->sysfs);
  68         free(d);
  69 }
  70
  71 void device_attach(Device *d, Seat *s) {
  72         Device *i;
  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
 105         if (!had_master && d->master)
 106                 seat_send_changed(s, "CanGraphical", NULL);
 107 }