src/libsystemd/sd-device/device-private.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <ctype.h>
   4 #include <net/if.h>
   5 #include <sys/types.h>
   6
   7 #include "sd-device.h"
   8
   9 #include "alloc-util.h"
  10 #include "device-internal.h"
  11 #include "device-private.h"
  12 #include "device-util.h"
  13 #include "fd-util.h"
  14 #include "fileio.h"
  15 #include "fs-util.h"
  16 #include "hashmap.h"
  17 #include "macro.h"
  18 #include "mkdir.h"
  19 #include "parse-util.h"
  20 #include "path-util.h"
  21 #include "refcnt.h"
  22 #include "set.h"
  23 #include "string-table.h"
  24 #include "string-util.h"
  25 #include "strv.h"
  26 #include "strxcpyx.h"
  27 #include "tmpfile-util.h"
  28 #include "user-util.h"
  29 #include "util.h"
  30
  31 int device_add_property(sd_device *device, const char *key, const char *value) {
  32         int r;
  33
  34         assert(device);
  35         assert(key);
  36
  37         r = device_add_property_aux(device, key, value, false);
  38         if (r < 0)
  39                 return r;
  40
  41         if (key[0] != '.') {
  42                 r = device_add_property_aux(device, key, value, true);
  43                 if (r < 0)
  44                         return r;
  45         }
  46
  47         return 0;
  48 }
  49
  50 void device_set_devlink_priority(sd_device *device, int priority) {
  51         assert(device);
  52
  53         device->devlink_priority = priority;
  54 }
  55
  56 void device_set_is_initialized(sd_device *device) {
  57         assert(device);
  58
  59         device->is_initialized = true;
  60 }
  61
  62 int device_ensure_usec_initialized(sd_device *device, sd_device *device_old) {
  63         usec_t when;
  64
  65         assert(device);
  66
  67         if (device_old && device_old->usec_initialized > 0)
  68                 when = device_old->usec_initialized;
  69         else
  70                 when = now(CLOCK_MONOTONIC);
  71
  72         return device_set_usec_initialized(device, when);
  73 }
  74
  75 uint64_t device_get_properties_generation(sd_device *device) {
  76         assert(device);
  77
  78         return device->properties_generation;
  79 }
  80
  81 uint64_t device_get_tags_generation(sd_device *device) {
  82         assert(device);
  83
  84         return device->tags_generation;
  85 }
  86
  87 uint64_t device_get_devlinks_generation(sd_device *device) {
  88         assert(device);
  89
  90         return device->devlinks_generation;
  91 }
  92
  93 int device_get_devnode_mode(sd_device *device, mode_t *mode) {
  94         int r;
  95
  96         assert(device);
  97
  98         r = device_read_db(device);
  99         if (r < 0)
 100                 return r;
 101
 102         if (device->devmode == (mode_t) -1)
 103                 return -ENOENT;
 104
 105         if (mode)
 106                 *mode = device->devmode;
 107
 108         return 0;
 109 }
 110
 111 int device_get_devnode_uid(sd_device *device, uid_t *uid) {
 112         int r;
 113
 114         assert(device);
 115
 116         r = device_read_db(device);
 117         if (r < 0)
 118                 return r;
 119
 120         if (device->devuid == (uid_t) -1)
 121                 return -ENOENT;
 122
 123         if (uid)
 124                 *uid = device->devuid;
 125
 126         return 0;
 127 }
 128
 129 static int device_set_devuid(sd_device *device, const char *uid) {
 130         unsigned u;
 131         int r;
 132
 133         assert(device);
 134         assert(uid);
 135
 136         r = safe_atou(uid, &u);
 137         if (r < 0)
 138                 return r;
 139
 140         r = device_add_property_internal(device, "DEVUID", uid);
 141         if (r < 0)
 142                 return r;
 143
 144         device->devuid = u;
 145
 146         return 0;
 147 }
 148
 149 int device_get_devnode_gid(sd_device *device, gid_t *gid) {
 150         int r;
 151
 152         assert(device);
 153
 154         r = device_read_db(device);
 155         if (r < 0)
 156                 return r;
 157
 158         if (device->devgid == (gid_t) -1)
 159                 return -ENOENT;
 160
 161         if (gid)
 162                 *gid = device->devgid;
 163
 164         return 0;
 165 }
 166
 167 static int device_set_devgid(sd_device *device, const char *gid) {
 168         unsigned g;
 169         int r;
 170
 171         assert(device);
 172         assert(gid);
 173
 174         r = safe_atou(gid, &g);
 175         if (r < 0)
 176                 return r;
 177
 178         r = device_add_property_internal(device, "DEVGID", gid);
 179         if (r < 0)
 180                 return r;
 181
 182         device->devgid = g;
 183
 184         return 0;
 185 }
 186
 187 static int device_amend(sd_device *device, const char *key, const char *value) {
 188         int r;
 189
 190         assert(device);
 191         assert(key);
 192         assert(value);
 193
 194         if (streq(key, "DEVPATH")) {
 195                 char *path;
 196
 197                 path = strjoina("/sys", value);
 198
 199                 /* the caller must verify or trust this data (e.g., if it comes from the kernel) */
 200                 r = device_set_syspath(device, path, false);
 201                 if (r < 0)
 202                         return log_device_debug_errno(device, r, "sd-device: Failed to set syspath to '%s': %m", path);
 203         } else if (streq(key, "SUBSYSTEM")) {
 204                 r = device_set_subsystem(device, value);
 205                 if (r < 0)
 206                         return log_device_debug_errno(device, r, "sd-device: Failed to set subsystem to '%s': %m", value);
 207         } else if (streq(key, "DEVTYPE")) {
 208                 r = device_set_devtype(device, value);
 209                 if (r < 0)
 210                         return log_device_debug_errno(device, r, "sd-device: Failed to set devtype to '%s': %m", value);
 211         } else if (streq(key, "DEVNAME")) {
 212                 r = device_set_devname(device, value);
 213                 if (r < 0)
 214                         return log_device_debug_errno(device, r, "sd-device: Failed to set devname to '%s': %m", value);
 215         } else if (streq(key, "USEC_INITIALIZED")) {
 216                 usec_t t;
 217
 218                 r = safe_atou64(value, &t);
 219                 if (r < 0)
 220                         return log_device_debug_errno(device, r, "sd-device: Failed to parse timestamp '%s': %m", value);
 221
 222                 r = device_set_usec_initialized(device, t);
 223                 if (r < 0)
 224                         return log_device_debug_errno(device, r, "sd-device: Failed to set usec-initialized to '%s': %m", value);
 225         } else if (streq(key, "DRIVER")) {
 226                 r = device_set_driver(device, value);
 227                 if (r < 0)
 228                         return log_device_debug_errno(device, r, "sd-device: Failed to set driver to '%s': %m", value);
 229         } else if (streq(key, "IFINDEX")) {
 230                 r = device_set_ifindex(device, value);
 231                 if (r < 0)
 232                         return log_device_debug_errno(device, r, "sd-device: Failed to set ifindex to '%s': %m", value);
 233         } else if (streq(key, "DEVMODE")) {
 234                 r = device_set_devmode(device, value);
 235                 if (r < 0)
 236                         return log_device_debug_errno(device, r, "sd-device: Failed to set devmode to '%s': %m", value);
 237         } else if (streq(key, "DEVUID")) {
 238                 r = device_set_devuid(device, value);
 239                 if (r < 0)
 240                         return log_device_debug_errno(device, r, "sd-device: Failed to set devuid to '%s': %m", value);
 241         } else if (streq(key, "DEVGID")) {
 242                 r = device_set_devgid(device, value);
 243                 if (r < 0)
 244                         return log_device_debug_errno(device, r, "sd-device: Failed to set devgid to '%s': %m", value);
 245         } else if (streq(key, "DEVLINKS")) {
 246                 const char *word, *state;
 247                 size_t l;
 248
 249                 FOREACH_WORD(word, l, value, state) {
 250                         char devlink[l + 1];
 251
 252                         strncpy(devlink, word, l);
 253                         devlink[l] = '\0';
 254
 255                         r = device_add_devlink(device, devlink);
 256                         if (r < 0)
 257                                 return log_device_debug_errno(device, r, "sd-device: Failed to add devlink '%s': %m", devlink);
 258                 }
 259         } else if (streq(key, "TAGS")) {
 260                 const char *word, *state;
 261                 size_t l;
 262
 263                 FOREACH_WORD_SEPARATOR(word, l, value, ":", state) {
 264                         char tag[l + 1];
 265
 266                         (void) strncpy(tag, word, l);
 267                         tag[l] = '\0';
 268
 269                         r = device_add_tag(device, tag);
 270                         if (r < 0)
 271                                 return log_device_debug_errno(device, r, "sd-device: Failed to add tag '%s': %m", tag);
 272                 }
 273         } else {
 274                 r = device_add_property_internal(device, key, value);
 275                 if (r < 0)
 276                         return log_device_debug_errno(device, r, "sd-device: Failed to add property '%s=%s': %m", key, value);
 277         }
 278
 279         return 0;
 280 }
 281
 282 static const char* const device_action_table[_DEVICE_ACTION_MAX] = {
 283         [DEVICE_ACTION_ADD] = "add",
 284         [DEVICE_ACTION_REMOVE] = "remove",
 285         [DEVICE_ACTION_CHANGE] = "change",
 286         [DEVICE_ACTION_MOVE] = "move",
 287         [DEVICE_ACTION_ONLINE] = "online",
 288         [DEVICE_ACTION_OFFLINE] = "offline",
 289         [DEVICE_ACTION_BIND] = "bind",
 290         [DEVICE_ACTION_UNBIND] = "unbind",
 291 };
 292
 293 DEFINE_STRING_TABLE_LOOKUP(device_action, DeviceAction);
 294
 295 static int device_append(sd_device *device, char *key, const char **_major, const char **_minor, uint64_t *_seqnum,
 296                          DeviceAction *_action) {
 297         DeviceAction action = _DEVICE_ACTION_INVALID;
 298         uint64_t seqnum = 0;
 299         const char *major = NULL, *minor = NULL;
 300         char *value;
 301         int r;
 302
 303         assert(device);
 304         assert(key);
 305         assert(_major);
 306         assert(_minor);
 307         assert(_seqnum);
 308         assert(_action);
 309
 310         value = strchr(key, '=');
 311         if (!value) {
 312                 log_device_debug(device, "sd-device: Not a key-value pair: '%s'", key);
 313                 return -EINVAL;
 314         }
 315
 316         *value = '\0';
 317
 318         value++;
 319
 320         if (streq(key, "MAJOR"))
 321                 major = value;
 322         else if (streq(key, "MINOR"))
 323                 minor = value;
 324         else {
 325                 if (streq(key, "ACTION")) {
 326                         action = device_action_from_string(value);
 327                         if (action == _DEVICE_ACTION_INVALID)
 328                                 return -EINVAL;
 329                 } else if (streq(key, "SEQNUM")) {
 330                         r = safe_atou64(value, &seqnum);
 331                         if (r < 0)
 332                                 return r;
 333                         else if (seqnum == 0)
 334                                  /* kernel only sends seqnum > 0 */
 335                                 return -EINVAL;
 336                 }
 337
 338                 r = device_amend(device, key, value);
 339                 if (r < 0)
 340                         return r;
 341         }
 342
 343         if (major != 0)
 344                 *_major = major;
 345
 346         if (minor != 0)
 347                 *_minor = minor;
 348
 349         if (action != _DEVICE_ACTION_INVALID)
 350                 *_action = action;
 351
 352         if (seqnum > 0)
 353                 *_seqnum = seqnum;
 354
 355         return 0;
 356 }
 357
 358 void device_seal(sd_device *device) {
 359         assert(device);
 360
 361         device->sealed = true;
 362 }
 363
 364 static int device_verify(sd_device *device, DeviceAction action, uint64_t seqnum) {
 365         assert(device);
 366
 367         if (!device->devpath || !device->subsystem || action == _DEVICE_ACTION_INVALID || seqnum == 0) {
 368                 log_device_debug(device, "sd-device: Device created from strv or nulstr lacks devpath, subsystem, action or seqnum.");
 369                 return -EINVAL;
 370         }
 371
 372         device->sealed = true;
 373
 374         return 0;
 375 }
 376
 377 int device_new_from_strv(sd_device **ret, char **strv) {
 378         _cleanup_(sd_device_unrefp) sd_device *device = NULL;
 379         char **key;
 380         const char *major = NULL, *minor = NULL;
 381         DeviceAction action = _DEVICE_ACTION_INVALID;
 382         uint64_t seqnum = 0;
 383         int r;
 384
 385         assert(ret);
 386         assert(strv);
 387
 388         r = device_new_aux(&device);
 389         if (r < 0)
 390                 return r;
 391
 392         STRV_FOREACH(key, strv) {
 393                 r = device_append(device, *key, &major, &minor, &seqnum, &action);
 394                 if (r < 0)
 395                         return r;
 396         }
 397
 398         if (major) {
 399                 r = device_set_devnum(device, major, minor);
 400                 if (r < 0)
 401                         return log_device_debug_errno(device, r, "sd-device: Failed to set devnum %s:%s: %m", major, minor);
 402         }
 403
 404         r = device_verify(device, action, seqnum);
 405         if (r < 0)
 406                 return r;
 407
 408         *ret = TAKE_PTR(device);
 409
 410         return 0;
 411 }
 412
 413 int device_new_from_nulstr(sd_device **ret, uint8_t *nulstr, size_t len) {
 414         _cleanup_(sd_device_unrefp) sd_device *device = NULL;
 415         const char *major = NULL, *minor = NULL;
 416         DeviceAction action = _DEVICE_ACTION_INVALID;
 417         uint64_t seqnum = 0;
 418         unsigned i = 0;
 419         int r;
 420
 421         assert(ret);
 422         assert(nulstr);
 423         assert(len);
 424
 425         r = device_new_aux(&device);
 426         if (r < 0)
 427                 return r;
 428
 429         while (i < len) {
 430                 char *key;
 431                 const char *end;
 432
 433                 key = (char*)&nulstr[i];
 434                 end = memchr(key, '\0', len - i);
 435                 if (!end) {
 436                         log_device_debug(device, "sd-device: Failed to parse nulstr");
 437                         return -EINVAL;
 438                 }
 439                 i += end - key + 1;
 440
 441                 r = device_append(device, key, &major, &minor, &seqnum, &action);
 442                 if (r < 0)
 443                         return r;
 444         }
 445
 446         if (major) {
 447                 r = device_set_devnum(device, major, minor);
 448                 if (r < 0)
 449                         return log_device_debug_errno(device, r, "sd-device: Failed to set devnum %s:%s: %m", major, minor);
 450         }
 451
 452         r = device_verify(device, action, seqnum);
 453         if (r < 0)
 454                 return r;
 455
 456         *ret = TAKE_PTR(device);
 457
 458         return 0;
 459 }
 460
 461 static int device_update_properties_bufs(sd_device *device) {
 462         const char *val, *prop;
 463         _cleanup_free_ char **buf_strv = NULL;
 464         _cleanup_free_ uint8_t *buf_nulstr = NULL;
 465         size_t allocated_nulstr = 0;
 466         size_t nulstr_len = 0, num = 0, i = 0;
 467
 468         assert(device);
 469
 470         if (!device->properties_buf_outdated)
 471                 return 0;
 472
 473         FOREACH_DEVICE_PROPERTY(device, prop, val) {
 474                 size_t len = 0;
 475
 476                 len = strlen(prop) + 1 + strlen(val);
 477
 478                 buf_nulstr = GREEDY_REALLOC0(buf_nulstr, allocated_nulstr, nulstr_len + len + 2);
 479                 if (!buf_nulstr)
 480                         return -ENOMEM;
 481
 482                 strscpyl((char *)buf_nulstr + nulstr_len, len + 1, prop, "=", val, NULL);
 483                 nulstr_len += len + 1;
 484                 ++num;
 485         }
 486
 487         /* build buf_strv from buf_nulstr */
 488         buf_strv = new0(char *, num + 1);
 489         if (!buf_strv)
 490                 return -ENOMEM;
 491
 492         NULSTR_FOREACH(val, (char*) buf_nulstr) {
 493                 buf_strv[i] = (char *) val;
 494                 assert(i < num);
 495                 i++;
 496         }
 497
 498         free_and_replace(device->properties_nulstr, buf_nulstr);
 499         device->properties_nulstr_len = nulstr_len;
 500         free_and_replace(device->properties_strv, buf_strv);
 501
 502         device->properties_buf_outdated = false;
 503
 504         return 0;
 505 }
 506
 507 int device_get_properties_nulstr(sd_device *device, const uint8_t **nulstr, size_t *len) {
 508         int r;
 509
 510         assert(device);
 511         assert(nulstr);
 512         assert(len);
 513
 514         r = device_update_properties_bufs(device);
 515         if (r < 0)
 516                 return r;
 517
 518         *nulstr = device->properties_nulstr;
 519         *len = device->properties_nulstr_len;
 520
 521         return 0;
 522 }
 523
 524 int device_get_properties_strv(sd_device *device, char ***strv) {
 525         int r;
 526
 527         assert(device);
 528         assert(strv);
 529
 530         r = device_update_properties_bufs(device);
 531         if (r < 0)
 532                 return r;
 533
 534         *strv = device->properties_strv;
 535
 536         return 0;
 537 }
 538
 539 int device_get_devlink_priority(sd_device *device, int *priority) {
 540         int r;
 541
 542         assert(device);
 543         assert(priority);
 544
 545         r = device_read_db(device);
 546         if (r < 0)
 547                 return r;
 548
 549         *priority = device->devlink_priority;
 550
 551         return 0;
 552 }
 553
 554 int device_get_watch_handle(sd_device *device, int *handle) {
 555         int r;
 556
 557         assert(device);
 558
 559         r = device_read_db(device);
 560         if (r < 0)
 561                 return r;
 562
 563         if (device->watch_handle < 0)
 564                 return -ENOENT;
 565
 566         if (handle)
 567                 *handle = device->watch_handle;
 568
 569         return 0;
 570 }
 571
 572 void device_set_watch_handle(sd_device *device, int handle) {
 573         assert(device);
 574
 575         device->watch_handle = handle;
 576 }
 577
 578 int device_rename(sd_device *device, const char *name) {
 579         _cleanup_free_ char *dirname = NULL;
 580         char *new_syspath;
 581         const char *interface;
 582         int r;
 583
 584         assert(device);
 585         assert(name);
 586
 587         dirname = dirname_malloc(device->syspath);
 588         if (!dirname)
 589                 return -ENOMEM;
 590
 591         new_syspath = strjoina(dirname, "/", name);
 592
 593         /* the user must trust that the new name is correct */
 594         r = device_set_syspath(device, new_syspath, false);
 595         if (r < 0)
 596                 return r;
 597
 598         r = sd_device_get_property_value(device, "INTERFACE", &interface);
 599         if (r >= 0) {
 600                 /* like DEVPATH_OLD, INTERFACE_OLD is not saved to the db, but only stays around for the current event */
 601                 r = device_add_property_internal(device, "INTERFACE_OLD", interface);
 602                 if (r < 0)
 603                         return r;
 604
 605                 r = device_add_property_internal(device, "INTERFACE", name);
 606                 if (r < 0)
 607                         return r;
 608         } else if (r != -ENOENT)
 609                 return r;
 610
 611         return 0;
 612 }
 613
 614 int device_shallow_clone(sd_device *old_device, sd_device **new_device) {
 615         _cleanup_(sd_device_unrefp) sd_device *ret = NULL;
 616         int r;
 617
 618         assert(old_device);
 619         assert(new_device);
 620
 621         r = device_new_aux(&ret);
 622         if (r < 0)
 623                 return r;
 624
 625         r = device_set_syspath(ret, old_device->syspath, false);
 626         if (r < 0)
 627                 return r;
 628
 629         r = device_set_subsystem(ret, old_device->subsystem);
 630         if (r < 0)
 631                 return r;
 632
 633         ret->devnum = old_device->devnum;
 634
 635         *new_device = TAKE_PTR(ret);
 636
 637         return 0;
 638 }
 639
 640 int device_clone_with_db(sd_device *old_device, sd_device **new_device) {
 641         _cleanup_(sd_device_unrefp) sd_device *ret = NULL;
 642         int r;
 643
 644         assert(old_device);
 645         assert(new_device);
 646
 647         r = device_shallow_clone(old_device, &ret);
 648         if (r < 0)
 649                 return r;
 650
 651         r = device_read_db(ret);
 652         if (r < 0)
 653                 return r;
 654
 655         ret->sealed = true;
 656
 657         *new_device = TAKE_PTR(ret);
 658
 659         return 0;
 660 }
 661
 662 int device_new_from_synthetic_event(sd_device **new_device, const char *syspath, const char *action) {
 663         _cleanup_(sd_device_unrefp) sd_device *ret = NULL;
 664         int r;
 665
 666         assert(new_device);
 667         assert(syspath);
 668         assert(action);
 669
 670         r = sd_device_new_from_syspath(&ret, syspath);
 671         if (r < 0)
 672                 return r;
 673
 674         r = device_read_uevent_file(ret);
 675         if (r < 0)
 676                 return r;
 677
 678         r = device_add_property_internal(ret, "ACTION", action);
 679         if (r < 0)
 680                 return r;
 681
 682         *new_device = TAKE_PTR(ret);
 683
 684         return 0;
 685 }
 686
 687 int device_new_from_stat_rdev(sd_device **ret, const struct stat *st) {
 688         char type;
 689
 690         assert(ret);
 691         assert(st);
 692
 693         if (S_ISBLK(st->st_mode))
 694                 type = 'b';
 695         else if (S_ISCHR(st->st_mode))
 696                 type = 'c';
 697         else
 698                 return -ENOTTY;
 699
 700         return sd_device_new_from_devnum(ret, type, st->st_rdev);
 701 }
 702
 703 int device_copy_properties(sd_device *device_dst, sd_device *device_src) {
 704         const char *property, *value;
 705         Iterator i;
 706         int r;
 707
 708         assert(device_dst);
 709         assert(device_src);
 710
 711         r = device_properties_prepare(device_src);
 712         if (r < 0)
 713                 return r;
 714
 715         ORDERED_HASHMAP_FOREACH_KEY(value, property, device_src->properties_db, i) {
 716                 r = device_add_property_aux(device_dst, property, value, true);
 717                 if (r < 0)
 718                         return r;
 719         }
 720
 721         ORDERED_HASHMAP_FOREACH_KEY(value, property, device_src->properties, i) {
 722                 r = device_add_property_aux(device_dst, property, value, false);
 723                 if (r < 0)
 724                         return r;
 725         }
 726
 727         return 0;
 728 }
 729
 730 void device_cleanup_tags(sd_device *device) {
 731         assert(device);
 732
 733         set_free_free(device->tags);
 734         device->tags = NULL;
 735         device->property_tags_outdated = true;
 736         device->tags_generation++;
 737 }
 738
 739 void device_cleanup_devlinks(sd_device *device) {
 740         assert(device);
 741
 742         set_free_free(device->devlinks);
 743         device->devlinks = NULL;
 744         device->property_devlinks_outdated = true;
 745         device->devlinks_generation++;
 746 }
 747
 748 void device_remove_tag(sd_device *device, const char *tag) {
 749         assert(device);
 750         assert(tag);
 751
 752         free(set_remove(device->tags, tag));
 753         device->property_tags_outdated = true;
 754         device->tags_generation++;
 755 }
 756
 757 static int device_tag(sd_device *device, const char *tag, bool add) {
 758         const char *id;
 759         char *path;
 760         int r;
 761
 762         assert(device);
 763         assert(tag);
 764
 765         r = device_get_id_filename(device, &id);
 766         if (r < 0)
 767                 return r;
 768
 769         path = strjoina("/run/udev/tags/", tag, "/", id);
 770
 771         if (add) {
 772                 r = touch_file(path, true, USEC_INFINITY, UID_INVALID, GID_INVALID, 0444);
 773                 if (r < 0)
 774                         return r;
 775         } else {
 776                 r = unlink(path);
 777                 if (r < 0 && errno != ENOENT)
 778                         return -errno;
 779         }
 780
 781         return 0;
 782 }
 783
 784 int device_tag_index(sd_device *device, sd_device *device_old, bool add) {
 785         const char *tag;
 786         int r = 0, k;
 787
 788         if (add && device_old) {
 789                 /* delete possible left-over tags */
 790                 FOREACH_DEVICE_TAG(device_old, tag) {
 791                         if (!sd_device_has_tag(device, tag)) {
 792                                 k = device_tag(device_old, tag, false);
 793                                 if (r >= 0 && k < 0)
 794                                         r = k;
 795                         }
 796                 }
 797         }
 798
 799         FOREACH_DEVICE_TAG(device, tag) {
 800                 k = device_tag(device, tag, add);
 801                 if (r >= 0 && k < 0)
 802                         r = k;
 803         }
 804
 805         return r;
 806 }
 807
 808 static bool device_has_info(sd_device *device) {
 809         assert(device);
 810
 811         if (!set_isempty(device->devlinks))
 812                 return true;
 813
 814         if (device->devlink_priority != 0)
 815                 return true;
 816
 817         if (!ordered_hashmap_isempty(device->properties_db))
 818                 return true;
 819
 820         if (!set_isempty(device->tags))
 821                 return true;
 822
 823         if (device->watch_handle >= 0)
 824                 return true;
 825
 826         return false;
 827 }
 828
 829 void device_set_db_persist(sd_device *device) {
 830         assert(device);
 831
 832         device->db_persist = true;
 833 }
 834
 835 int device_update_db(sd_device *device) {
 836         const char *id;
 837         char *path;
 838         _cleanup_fclose_ FILE *f = NULL;
 839         _cleanup_free_ char *path_tmp = NULL;
 840         bool has_info;
 841         int r;
 842
 843         assert(device);
 844
 845         has_info = device_has_info(device);
 846
 847         r = device_get_id_filename(device, &id);
 848         if (r < 0)
 849                 return r;
 850
 851         path = strjoina("/run/udev/data/", id);
 852
 853         /* do not store anything for otherwise empty devices */
 854         if (!has_info && major(device->devnum) == 0 && device->ifindex == 0) {
 855                 r = unlink(path);
 856                 if (r < 0 && errno != ENOENT)
 857                         return -errno;
 858
 859                 return 0;
 860         }
 861
 862         /* write a database file */
 863         r = mkdir_parents(path, 0755);
 864         if (r < 0)
 865                 return r;
 866
 867         r = fopen_temporary(path, &f, &path_tmp);
 868         if (r < 0)
 869                 return r;
 870
 871         /*
 872          * set 'sticky' bit to indicate that we should not clean the
 873          * database when we transition from initramfs to the real root
 874          */
 875         if (device->db_persist) {
 876                 r = fchmod(fileno(f), 01644);
 877                 if (r < 0) {
 878                         r = -errno;
 879                         goto fail;
 880                 }
 881         } else {
 882                 r = fchmod(fileno(f), 0644);
 883                 if (r < 0) {
 884                         r = -errno;
 885                         goto fail;
 886                 }
 887         }
 888
 889         if (has_info) {
 890                 const char *property, *value, *tag;
 891                 Iterator i;
 892
 893                 if (major(device->devnum) > 0) {
 894                         const char *devlink;
 895
 896                         FOREACH_DEVICE_DEVLINK(device, devlink)
 897                                 fprintf(f, "S:%s\n", devlink + STRLEN("/dev/"));
 898
 899                         if (device->devlink_priority != 0)
 900                                 fprintf(f, "L:%i\n", device->devlink_priority);
 901
 902                         if (device->watch_handle >= 0)
 903                                 fprintf(f, "W:%i\n", device->watch_handle);
 904                 }
 905
 906                 if (device->usec_initialized > 0)
 907                         fprintf(f, "I:"USEC_FMT"\n", device->usec_initialized);
 908
 909                 ORDERED_HASHMAP_FOREACH_KEY(value, property, device->properties_db, i)
 910                         fprintf(f, "E:%s=%s\n", property, value);
 911
 912                 FOREACH_DEVICE_TAG(device, tag)
 913                         fprintf(f, "G:%s\n", tag);
 914         }
 915
 916         r = fflush_and_check(f);
 917         if (r < 0)
 918                 goto fail;
 919
 920         r = rename(path_tmp, path);
 921         if (r < 0) {
 922                 r = -errno;
 923                 goto fail;
 924         }
 925
 926         log_device_debug(device, "sd-device: Created %s file '%s' for '%s'", has_info ? "db" : "empty",
 927                          path, device->devpath);
 928
 929         return 0;
 930
 931 fail:
 932         (void) unlink(path);
 933         (void) unlink(path_tmp);
 934
 935         return log_device_debug_errno(device, r, "sd-device: Failed to create %s file '%s' for '%s'", has_info ? "db" : "empty", path, device->devpath);
 936 }
 937
 938 int device_delete_db(sd_device *device) {
 939         const char *id;
 940         char *path;
 941         int r;
 942
 943         assert(device);
 944
 945         r = device_get_id_filename(device, &id);
 946         if (r < 0)
 947                 return r;
 948
 949         path = strjoina("/run/udev/data/", id);
 950
 951         r = unlink(path);
 952         if (r < 0 && errno != ENOENT)
 953                 return -errno;
 954
 955         return 0;
 956 }