src/login/logind-button.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <fcntl.h>
   5 #include <string.h>
   6 #include <sys/ioctl.h>
   7 #include <unistd.h>
   8 #include <linux/input.h>
   9
  10 #include "sd-messages.h"
  11
  12 #include "alloc-util.h"
  13 #include "fd-util.h"
  14 #include "logind-button.h"
  15 #include "string-util.h"
  16 #include "util.h"
  17
  18 #define CONST_MAX4(a, b, c, d) CONST_MAX(CONST_MAX(a, b), CONST_MAX(c, d))
  19
  20 #define ULONG_BITS (sizeof(unsigned long)*8)
  21
  22 static bool bitset_get(const unsigned long *bits, unsigned i) {
  23         return (bits[i / ULONG_BITS] >> (i % ULONG_BITS)) & 1UL;
  24 }
  25
  26 static void bitset_put(unsigned long *bits, unsigned i) {
  27         bits[i / ULONG_BITS] |= (unsigned long) 1 << (i % ULONG_BITS);
  28 }
  29
  30 Button* button_new(Manager *m, const char *name) {
  31         Button *b;
  32
  33         assert(m);
  34         assert(name);
  35
  36         b = new0(Button, 1);
  37         if (!b)
  38                 return NULL;
  39
  40         b->name = strdup(name);
  41         if (!b->name)
  42                 return mfree(b);
  43
  44         if (hashmap_put(m->buttons, b->name, b) < 0) {
  45                 free(b->name);
  46                 return mfree(b);
  47         }
  48
  49         b->manager = m;
  50         b->fd = -1;
  51
  52         return b;
  53 }
  54
  55 void button_free(Button *b) {
  56         assert(b);
  57
  58         hashmap_remove(b->manager->buttons, b->name);
  59
  60         sd_event_source_unref(b->io_event_source);
  61         sd_event_source_unref(b->check_event_source);
  62
  63         if (b->fd >= 0)
  64                 /* If the device has been unplugged close() returns
  65                  * ENODEV, let's ignore this, hence we don't use
  66                  * safe_close() */
  67                 (void) close(b->fd);
  68
  69         free(b->name);
  70         free(b->seat);
  71         free(b);
  72 }
  73
  74 int button_set_seat(Button *b, const char *sn) {
  75         char *s;
  76
  77         assert(b);
  78         assert(sn);
  79
  80         s = strdup(sn);
  81         if (!s)
  82                 return -ENOMEM;
  83
  84         free(b->seat);
  85         b->seat = s;
  86
  87         return 0;
  88 }
  89
  90 static void button_lid_switch_handle_action(Manager *manager, bool is_edge) {
  91         HandleAction handle_action;
  92
  93         assert(manager);
  94
  95         /* If we are docked or on external power, handle the lid switch
  96          * differently */
  97         if (manager_is_docked_or_external_displays(manager))
  98                 handle_action = manager->handle_lid_switch_docked;
  99         else if (manager->handle_lid_switch_ep != _HANDLE_ACTION_INVALID &&
 100                  manager_is_on_external_power())
 101                 handle_action = manager->handle_lid_switch_ep;
 102         else
 103                 handle_action = manager->handle_lid_switch;
 104
 105         manager_handle_action(manager, INHIBIT_HANDLE_LID_SWITCH, handle_action, manager->lid_switch_ignore_inhibited, is_edge);
 106 }
 107
 108 static int button_recheck(sd_event_source *e, void *userdata) {
 109         Button *b = userdata;
 110
 111         assert(b);
 112         assert(b->lid_closed);
 113
 114         button_lid_switch_handle_action(b->manager, false);
 115         return 1;
 116 }
 117
 118 static int button_install_check_event_source(Button *b) {
 119         int r;
 120         assert(b);
 121
 122         /* Install a post handler, so that we keep rechecking as long as the lid is closed. */
 123
 124         if (b->check_event_source)
 125                 return 0;
 126
 127         r = sd_event_add_post(b->manager->event, &b->check_event_source, button_recheck, b);
 128         if (r < 0)
 129                 return r;
 130
 131         return sd_event_source_set_priority(b->check_event_source, SD_EVENT_PRIORITY_IDLE+1);
 132 }
 133
 134 static int button_dispatch(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 135         Button *b = userdata;
 136         struct input_event ev;
 137         ssize_t l;
 138
 139         assert(s);
 140         assert(fd == b->fd);
 141         assert(b);
 142
 143         l = read(b->fd, &ev, sizeof(ev));
 144         if (l < 0)
 145                 return errno != EAGAIN ? -errno : 0;
 146         if ((size_t) l < sizeof(ev))
 147                 return -EIO;
 148
 149         if (ev.type == EV_KEY && ev.value > 0) {
 150
 151                 switch (ev.code) {
 152
 153                 case KEY_POWER:
 154                 case KEY_POWER2:
 155                         log_struct(LOG_INFO,
 156                                    LOG_MESSAGE("Power key pressed."),
 157                                    "MESSAGE_ID=" SD_MESSAGE_POWER_KEY_STR);
 158
 159                         manager_handle_action(b->manager, INHIBIT_HANDLE_POWER_KEY, b->manager->handle_power_key, b->manager->power_key_ignore_inhibited, true);
 160                         break;
 161
 162                 /* The kernel is a bit confused here:
 163
 164                    KEY_SLEEP   = suspend-to-ram, which everybody else calls "suspend"
 165                    KEY_SUSPEND = suspend-to-disk, which everybody else calls "hibernate"
 166                 */
 167
 168                 case KEY_SLEEP:
 169                         log_struct(LOG_INFO,
 170                                    LOG_MESSAGE("Suspend key pressed."),
 171                                    "MESSAGE_ID=" SD_MESSAGE_SUSPEND_KEY_STR);
 172
 173                         manager_handle_action(b->manager, INHIBIT_HANDLE_SUSPEND_KEY, b->manager->handle_suspend_key, b->manager->suspend_key_ignore_inhibited, true);
 174                         break;
 175
 176                 case KEY_SUSPEND:
 177                         log_struct(LOG_INFO,
 178                                    LOG_MESSAGE("Hibernate key pressed."),
 179                                    "MESSAGE_ID=" SD_MESSAGE_HIBERNATE_KEY_STR);
 180
 181                         manager_handle_action(b->manager, INHIBIT_HANDLE_HIBERNATE_KEY, b->manager->handle_hibernate_key, b->manager->hibernate_key_ignore_inhibited, true);
 182                         break;
 183                 }
 184
 185         } else if (ev.type == EV_SW && ev.value > 0) {
 186
 187                 if (ev.code == SW_LID) {
 188                         log_struct(LOG_INFO,
 189                                    LOG_MESSAGE("Lid closed."),
 190                                    "MESSAGE_ID=" SD_MESSAGE_LID_CLOSED_STR);
 191
 192                         b->lid_closed = true;
 193                         button_lid_switch_handle_action(b->manager, true);
 194                         button_install_check_event_source(b);
 195
 196                 } else if (ev.code == SW_DOCK) {
 197                         log_struct(LOG_INFO,
 198                                    LOG_MESSAGE("System docked."),
 199                                    "MESSAGE_ID=" SD_MESSAGE_SYSTEM_DOCKED_STR);
 200
 201                         b->docked = true;
 202                 }
 203
 204         } else if (ev.type == EV_SW && ev.value == 0) {
 205
 206                 if (ev.code == SW_LID) {
 207                         log_struct(LOG_INFO,
 208                                    LOG_MESSAGE("Lid opened."),
 209                                    "MESSAGE_ID=" SD_MESSAGE_LID_OPENED_STR);
 210
 211                         b->lid_closed = false;
 212                         b->check_event_source = sd_event_source_unref(b->check_event_source);
 213
 214                 } else if (ev.code == SW_DOCK) {
 215                         log_struct(LOG_INFO,
 216                                    LOG_MESSAGE("System undocked."),
 217                                    "MESSAGE_ID=" SD_MESSAGE_SYSTEM_UNDOCKED_STR);
 218
 219                         b->docked = false;
 220                 }
 221         }
 222
 223         return 0;
 224 }
 225
 226 static int button_suitable(Button *b) {
 227         unsigned long types[CONST_MAX(EV_KEY, EV_SW)/ULONG_BITS+1];
 228
 229         assert(b);
 230         assert(b->fd);
 231
 232         if (ioctl(b->fd, EVIOCGBIT(EV_SYN, sizeof(types)), types) < 0)
 233                 return -errno;
 234
 235         if (bitset_get(types, EV_KEY)) {
 236                 unsigned long keys[CONST_MAX4(KEY_POWER, KEY_POWER2, KEY_SLEEP, KEY_SUSPEND)/ULONG_BITS+1];
 237
 238                 if (ioctl(b->fd, EVIOCGBIT(EV_KEY, sizeof(keys)), keys) < 0)
 239                         return -errno;
 240
 241                 if (bitset_get(keys, KEY_POWER) ||
 242                     bitset_get(keys, KEY_POWER2) ||
 243                     bitset_get(keys, KEY_SLEEP) ||
 244                     bitset_get(keys, KEY_SUSPEND))
 245                         return true;
 246         }
 247
 248         if (bitset_get(types, EV_SW)) {
 249                 unsigned long switches[CONST_MAX(SW_LID, SW_DOCK)/ULONG_BITS+1];
 250
 251                 if (ioctl(b->fd, EVIOCGBIT(EV_SW, sizeof(switches)), switches) < 0)
 252                         return -errno;
 253
 254                 if (bitset_get(switches, SW_LID) ||
 255                     bitset_get(switches, SW_DOCK))
 256                         return true;
 257         }
 258
 259         return false;
 260 }
 261
 262 static int button_set_mask(Button *b) {
 263         unsigned long
 264                 types[CONST_MAX(EV_KEY, EV_SW)/ULONG_BITS+1] = {},
 265                 keys[CONST_MAX4(KEY_POWER, KEY_POWER2, KEY_SLEEP, KEY_SUSPEND)/ULONG_BITS+1] = {},
 266                 switches[CONST_MAX(SW_LID, SW_DOCK)/ULONG_BITS+1] = {};
 267         struct input_mask mask;
 268
 269         assert(b);
 270         assert(b->fd >= 0);
 271
 272         bitset_put(types, EV_KEY);
 273         bitset_put(types, EV_SW);
 274
 275         mask = (struct input_mask) {
 276                 .type = EV_SYN,
 277                 .codes_size = sizeof(types),
 278                 .codes_ptr = PTR_TO_UINT64(types),
 279         };
 280
 281         if (ioctl(b->fd, EVIOCSMASK, &mask) < 0)
 282                 /* Log only at debug level if the kernel doesn't do EVIOCSMASK yet */
 283                 return log_full_errno(IN_SET(errno, ENOTTY, EOPNOTSUPP, EINVAL) ? LOG_DEBUG : LOG_WARNING,
 284                                       errno, "Failed to set EV_SYN event mask on /dev/input/%s: %m", b->name);
 285
 286         bitset_put(keys, KEY_POWER);
 287         bitset_put(keys, KEY_POWER2);
 288         bitset_put(keys, KEY_SLEEP);
 289         bitset_put(keys, KEY_SUSPEND);
 290
 291         mask = (struct input_mask) {
 292                 .type = EV_KEY,
 293                 .codes_size = sizeof(keys),
 294                 .codes_ptr = PTR_TO_UINT64(keys),
 295         };
 296
 297         if (ioctl(b->fd, EVIOCSMASK, &mask) < 0)
 298                 return log_warning_errno(errno, "Failed to set EV_KEY event mask on /dev/input/%s: %m", b->name);
 299
 300         bitset_put(switches, SW_LID);
 301         bitset_put(switches, SW_DOCK);
 302
 303         mask = (struct input_mask) {
 304                 .type = EV_SW,
 305                 .codes_size = sizeof(switches),
 306                 .codes_ptr = PTR_TO_UINT64(switches),
 307         };
 308
 309         if (ioctl(b->fd, EVIOCSMASK, &mask) < 0)
 310                 return log_warning_errno(errno, "Failed to set EV_SW event mask on /dev/input/%s: %m", b->name);
 311
 312         return 0;
 313 }
 314
 315 int button_open(Button *b) {
 316         char *p, name[256];
 317         int r;
 318
 319         assert(b);
 320
 321         b->fd = safe_close(b->fd);
 322
 323         p = strjoina("/dev/input/", b->name);
 324
 325         b->fd = open(p, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK);
 326         if (b->fd < 0)
 327                 return log_warning_errno(errno, "Failed to open %s: %m", p);
 328
 329         r = button_suitable(b);
 330         if (r < 0)
 331                 return log_warning_errno(r, "Failed to determine whether input device is relevant to us: %m");
 332         if (r == 0) {
 333                 log_debug("Device %s does not expose keys or switches relevant to us, ignoring.", p);
 334                 return -EADDRNOTAVAIL;
 335         }
 336
 337         if (ioctl(b->fd, EVIOCGNAME(sizeof(name)), name) < 0) {
 338                 r = log_error_errno(errno, "Failed to get input name: %m");
 339                 goto fail;
 340         }
 341
 342         (void) button_set_mask(b);
 343
 344         r = sd_event_add_io(b->manager->event, &b->io_event_source, b->fd, EPOLLIN, button_dispatch, b);
 345         if (r < 0) {
 346                 log_error_errno(r, "Failed to add button event: %m");
 347                 goto fail;
 348         }
 349
 350         log_info("Watching system buttons on /dev/input/%s (%s)", b->name, name);
 351
 352         return 0;
 353
 354 fail:
 355         b->fd = safe_close(b->fd);
 356         return r;
 357 }
 358
 359 int button_check_switches(Button *b) {
 360         unsigned long switches[CONST_MAX(SW_LID, SW_DOCK)/ULONG_BITS+1] = {};
 361         assert(b);
 362
 363         if (b->fd < 0)
 364                 return -EINVAL;
 365
 366         if (ioctl(b->fd, EVIOCGSW(sizeof(switches)), switches) < 0)
 367                 return -errno;
 368
 369         b->lid_closed = bitset_get(switches, SW_LID);
 370         b->docked = bitset_get(switches, SW_DOCK);
 371
 372         if (b->lid_closed)
 373                 button_install_check_event_source(b);
 374
 375         return 0;
 376 }