src/login/logind-device.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2011 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <string.h>
  21
  22 #include "alloc-util.h"
  23 #include "logind-device.h"
  24 #include "util.h"
  25
  26 Device* device_new(Manager *m, const char *sysfs, bool master) {
  27         Device *d;
  28
  29         assert(m);
  30         assert(sysfs);
  31
  32         d = new0(Device, 1);
  33         if (!d)
  34                 return NULL;
  35
  36         d->sysfs = strdup(sysfs);
  37         if (!d->sysfs) {
  38                 free(d);
  39                 return NULL;
  40         }
  41
  42         if (hashmap_put(m->devices, d->sysfs, d) < 0) {
  43                 free(d->sysfs);
  44                 free(d);
  45                 return NULL;
  46         }
  47
  48         d->manager = m;
  49         d->master = master;
  50         dual_timestamp_get(&d->timestamp);
  51
  52         return d;
  53 }
  54
  55 static void device_detach(Device *d) {
  56         Seat *s;
  57         SessionDevice *sd;
  58
  59         assert(d);
  60
  61         if (!d->seat)
  62                 return;
  63
  64         while ((sd = d->session_devices))
  65                 session_device_free(sd);
  66
  67         s = d->seat;
  68         LIST_REMOVE(devices, d->seat->devices, d);
  69         d->seat = NULL;
  70
  71         if (!seat_has_master_device(s)) {
  72                 seat_add_to_gc_queue(s);
  73                 seat_send_changed(s, "CanGraphical", NULL);
  74         }
  75 }
  76
  77 void device_free(Device *d) {
  78         assert(d);
  79
  80         device_detach(d);
  81
  82         hashmap_remove(d->manager->devices, d->sysfs);
  83
  84         free(d->sysfs);
  85         free(d);
  86 }
  87
  88 void device_attach(Device *d, Seat *s) {
  89         Device *i;
  90         bool had_master;
  91
  92         assert(d);
  93         assert(s);
  94
  95         if (d->seat == s)
  96                 return;
  97
  98         if (d->seat)
  99                 device_detach(d);
 100
 101         d->seat = s;
 102         had_master = seat_has_master_device(s);
 103
 104         /* We keep the device list sorted by the "master" flag. That is, master
 105          * devices are at the front, other devices at the tail. As there is no
 106          * way to easily add devices at the list-tail, we need to iterate the
 107          * list to find the first non-master device when adding non-master
 108          * devices. We assume there is only a few (normally 1) master devices
 109          * per seat, so we iterate only a few times. */
 110
 111         if (d->master || !s->devices)
 112                 LIST_PREPEND(devices, s->devices, d);
 113         else {
 114                 LIST_FOREACH(devices, i, s->devices) {
 115                         if (!i->devices_next || !i->master) {
 116                                 LIST_INSERT_AFTER(devices, s->devices, i, d);
 117                                 break;
 118                         }
 119                 }
 120         }
 121
 122         if (!had_master && d->master)
 123                 seat_send_changed(s, "CanGraphical", NULL);
 124 }