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                 return mfree(d);
  39
  40         if (hashmap_put(m->devices, d->sysfs, d) < 0) {
  41                 free(d->sysfs);
  42                 return mfree(d);
  43         }
  44
  45         d->manager = m;
  46         d->master = master;
  47         dual_timestamp_get(&d->timestamp);
  48
  49         return d;
  50 }
  51
  52 static void device_detach(Device *d) {
  53         Seat *s;
  54         SessionDevice *sd;
  55
  56         assert(d);
  57
  58         if (!d->seat)
  59                 return;
  60
  61         while ((sd = d->session_devices))
  62                 session_device_free(sd);
  63
  64         s = d->seat;
  65         LIST_REMOVE(devices, d->seat->devices, d);
  66         d->seat = NULL;
  67
  68         if (!seat_has_master_device(s)) {
  69                 seat_add_to_gc_queue(s);
  70                 seat_send_changed(s, "CanGraphical", NULL);
  71         }
  72 }
  73
  74 void device_free(Device *d) {
  75         assert(d);
  76
  77         device_detach(d);
  78
  79         hashmap_remove(d->manager->devices, d->sysfs);
  80
  81         free(d->sysfs);
  82         free(d);
  83 }
  84
  85 void device_attach(Device *d, Seat *s) {
  86         Device *i;
  87         bool had_master;
  88
  89         assert(d);
  90         assert(s);
  91
  92         if (d->seat == s)
  93                 return;
  94
  95         if (d->seat)
  96                 device_detach(d);
  97
  98         d->seat = s;
  99         had_master = seat_has_master_device(s);
 100
 101         /* We keep the device list sorted by the "master" flag. That is, master
 102          * devices are at the front, other devices at the tail. As there is no
 103          * way to easily add devices at the list-tail, we need to iterate the
 104          * list to find the first non-master device when adding non-master
 105          * devices. We assume there is only a few (normally 1) master devices
 106          * per seat, so we iterate only a few times. */
 107
 108         if (d->master || !s->devices)
 109                 LIST_PREPEND(devices, s->devices, d);
 110         else {
 111                 LIST_FOREACH(devices, i, s->devices) {
 112                         if (!i->devices_next || !i->master) {
 113                                 LIST_INSERT_AFTER(devices, s->devices, i, d);
 114                                 break;
 115                         }
 116                 }
 117         }
 118
 119         if (!had_master && d->master)
 120                 seat_send_changed(s, "CanGraphical", NULL);
 121 }