udev/lib/libudev-device.c

   1 /*
   2  * libudev - interface to udev device information
   3  *
   4  * Copyright (C) 2008 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <stddef.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25 #include <string.h>
  26 #include <dirent.h>
  27 #include <fcntl.h>
  28 #include <ctype.h>
  29 #include <sys/stat.h>
  30
  31 #include "libudev.h"
  32 #include "libudev-private.h"
  33
  34 struct udev_device {
  35         struct udev *udev;
  36         struct udev_device *parent_device;
  37         char *syspath;
  38         const char *devpath;
  39         char *sysname;
  40         const char *sysnum;
  41         char *devnode;
  42         char *subsystem;
  43         char *driver;
  44         char *action;
  45         char *devpath_old;
  46         char *physdevpath;
  47         char **envp;
  48         char *monitor_buf;
  49         size_t monitor_buf_len;
  50         struct udev_list_node devlinks_list;
  51         struct udev_list_node properties_list;
  52         struct udev_list_node sysattr_list;
  53         unsigned long long int seqnum;
  54         int event_timeout;
  55         int timeout;
  56         int num_fake_partitions;
  57         int devlink_priority;
  58         int refcount;
  59         dev_t devnum;
  60         unsigned int parent_set:1;
  61         unsigned int subsystem_set:1;
  62         unsigned int devlinks_uptodate:1;
  63         unsigned int envp_uptodate:1;
  64         unsigned int driver_set:1;
  65         unsigned int info_loaded:1;
  66         unsigned int ignore_remove:1;
  67 };
  68
  69 static size_t devpath_to_db_path(struct udev *udev, const char *devpath, char *filename, size_t len)
  70 {
  71         size_t start;
  72
  73         /* translate to location of db file */
  74         util_strlcpy(filename, udev_get_dev_path(udev), len);
  75         start = util_strlcat(filename, "/.udev/db/", len);
  76         util_strlcat(filename, devpath, len);
  77         return util_path_encode(&filename[start], len - start);
  78 }
  79
  80 int udev_device_read_db(struct udev_device *udev_device)
  81 {
  82         struct stat stats;
  83         char filename[UTIL_PATH_SIZE];
  84         char line[UTIL_LINE_SIZE];
  85         FILE *f;
  86
  87         devpath_to_db_path(udev_device->udev, udev_device->devpath, filename, sizeof(filename));
  88
  89         if (lstat(filename, &stats) != 0) {
  90                 info(udev_device->udev, "no db file to read %s: %m\n", filename);
  91                 return -1;
  92         }
  93         if ((stats.st_mode & S_IFMT) == S_IFLNK) {
  94                 char target[UTIL_PATH_SIZE];
  95                 char devnode[UTIL_PATH_SIZE];
  96                 int target_len;
  97                 char *next;
  98
  99                 target_len = readlink(filename, target, sizeof(target));
 100                 if (target_len > 0)
 101                         target[target_len] = '\0';
 102                 else {
 103                         info(udev_device->udev, "error reading db link %s: %m\n", filename);
 104                         return -1;
 105                 }
 106
 107                 next = strchr(target, ' ');
 108                 if (next != NULL) {
 109                         next[0] = '\0';
 110                         next = &next[1];
 111                 }
 112                 util_strlcpy(devnode, udev_get_dev_path(udev_device->udev), sizeof(devnode));
 113                 util_strlcat(devnode, "/", sizeof(devnode));
 114                 util_strlcat(devnode, target, sizeof(devnode));
 115                 udev_device_set_devnode(udev_device, devnode);
 116                 while (next != NULL) {
 117                         char devlink[UTIL_PATH_SIZE];
 118                         const char *lnk;
 119
 120                         lnk = next;
 121                         next = strchr(next, ' ');
 122                         if (next != NULL) {
 123                                 next[0] = '\0';
 124                                 next = &next[1];
 125                         }
 126                         util_strlcpy(devlink, udev_get_dev_path(udev_device->udev), sizeof(devlink));
 127                         util_strlcat(devlink, "/", sizeof(devlink));
 128                         util_strlcat(devlink, lnk, sizeof(devlink));
 129                         udev_device_add_devlink(udev_device, devlink);
 130                 }
 131                 info(udev_device->udev, "device %p filled with db symlink data '%s'\n", udev_device, udev_device->devnode);
 132                 return 0;
 133         }
 134
 135         f = fopen(filename, "r");
 136         if (f == NULL) {
 137                 info(udev_device->udev, "error reading db file %s: %m\n", filename);
 138                 return -1;
 139         }
 140         while (fgets(line, sizeof(line), f)) {
 141                 ssize_t len;
 142                 const char *val;
 143
 144                 len = strlen(line);
 145                 if (len < 4)
 146                         break;
 147                 line[len-1] = '\0';
 148                 val = &line[2];
 149                 switch(line[0]) {
 150                 case 'N':
 151                         util_strlcpy(filename, udev_get_dev_path(udev_device->udev), sizeof(filename));
 152                         util_strlcat(filename, "/", sizeof(filename));
 153                         util_strlcat(filename, val, sizeof(filename));
 154                         udev_device_set_devnode(udev_device, filename);
 155                         break;
 156                 case 'S':
 157                         util_strlcpy(filename, udev_get_dev_path(udev_device->udev), sizeof(filename));
 158                         util_strlcat(filename, "/", sizeof(filename));
 159                         util_strlcat(filename, val, sizeof(filename));
 160                         udev_device_add_devlink(udev_device, filename);
 161                         break;
 162                 case 'L':
 163                         udev_device_set_devlink_priority(udev_device, atoi(val));
 164                         break;
 165                 case 'T':
 166                         udev_device_set_event_timeout(udev_device, atoi(val));
 167                         break;
 168                 case 'A':
 169                         udev_device_set_num_fake_partitions(udev_device, atoi(val));
 170                         break;
 171                 case 'R':
 172                         udev_device_set_ignore_remove(udev_device, atoi(val));
 173                         break;
 174                 case 'E':
 175                         udev_device_add_property_from_string(udev_device, val);
 176                         break;
 177                 }
 178         }
 179         fclose(f);
 180
 181         info(udev_device->udev, "device %p filled with db file data\n", udev_device);
 182         return 0;
 183 }
 184
 185 int udev_device_read_uevent_file(struct udev_device *udev_device)
 186 {
 187         char filename[UTIL_PATH_SIZE];
 188         FILE *f;
 189         char line[UTIL_LINE_SIZE];
 190         int maj = 0;
 191         int min = 0;
 192
 193         util_strlcpy(filename, udev_device->syspath, sizeof(filename));
 194         util_strlcat(filename, "/uevent", sizeof(filename));
 195         f = fopen(filename, "r");
 196         if (f == NULL)
 197                 return -1;
 198
 199         while (fgets(line, sizeof(line), f)) {
 200                 char *pos;
 201
 202                 pos = strchr(line, '\n');
 203                 if (pos == NULL)
 204                         continue;
 205                 pos[0] = '\0';
 206
 207                 if (strncmp(line, "MAJOR=", 6) == 0)
 208                         maj = strtoull(&line[6], NULL, 10);
 209                 else if (strncmp(line, "MINOR=", 6) == 0)
 210                         min = strtoull(&line[6], NULL, 10);
 211
 212                 udev_device_add_property_from_string(udev_device, line);
 213         }
 214
 215         udev_device->devnum = makedev(maj, min);
 216
 217         fclose(f);
 218         return 0;
 219 }
 220
 221 static void device_load_info(struct udev_device *device)
 222 {
 223         device->info_loaded = 1;
 224         udev_device_read_uevent_file(device);
 225         udev_device_read_db(device);
 226 }
 227
 228 void udev_device_set_info_loaded(struct udev_device *device)
 229 {
 230         device->info_loaded = 1;
 231 }
 232
 233 struct udev_device *device_new(struct udev *udev)
 234 {
 235         struct udev_device *udev_device;
 236         struct udev_list_entry *list_entry;
 237
 238         if (udev == NULL)
 239                 return NULL;
 240
 241         udev_device = calloc(1, sizeof(struct udev_device));
 242         if (udev_device == NULL)
 243                 return NULL;
 244         udev_device->refcount = 1;
 245         udev_device->udev = udev;
 246         udev_list_init(&udev_device->devlinks_list);
 247         udev_list_init(&udev_device->properties_list);
 248         udev_list_init(&udev_device->sysattr_list);
 249         udev_device->event_timeout = -1;
 250         /* copy global properties */
 251         udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
 252                 udev_device_add_property(udev_device,
 253                                          udev_list_entry_get_name(list_entry),
 254                                          udev_list_entry_get_value(list_entry));
 255         info(udev_device->udev, "udev_device: %p created\n", udev_device);
 256         return udev_device;
 257 }
 258
 259 /**
 260  * udev_device_new_from_syspath:
 261  * @udev: udev library context
 262  * @syspath: sys device path including sys directory
 263  *
 264  * Create new udev device, and fill in information from the sys
 265  * device and the udev database entry. The sypath is the absolute
 266  * path to the device, including the sys mount point.
 267  *
 268  * The initial refcount is 1, and needs to be decremented to
 269  * release the ressources of the udev device.
 270  *
 271  * Returns: a new udev device, or #NULL, if it does not exist
 272  **/
 273 struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
 274 {
 275         size_t len;
 276         const char *subdir;
 277         char path[UTIL_PATH_SIZE];
 278         char *pos;
 279         struct stat statbuf;
 280         struct udev_device *udev_device;
 281
 282         if (udev == NULL)
 283                 return NULL;
 284         if (syspath == NULL)
 285                 return NULL;
 286
 287         /* path starts in sys */
 288         len = strlen(udev_get_sys_path(udev));
 289         if (strncmp(syspath, udev_get_sys_path(udev), len) != 0) {
 290                 info(udev, "not in sys :%s\n", syspath);
 291                 return NULL;
 292         }
 293
 294         /* path is not a root directory */
 295         subdir = &syspath[len+1];
 296         pos = strrchr(subdir, '/');
 297         if (pos == NULL || pos < &subdir[2]) {
 298                 info(udev, "not a subdir :%s\n", syspath);
 299                 return NULL;
 300         }
 301
 302         /* resolve possible symlink to real path */
 303         util_strlcpy(path, syspath, sizeof(path));
 304         util_resolve_sys_link(udev, path, sizeof(path));
 305
 306         /* try to resolve the silly block layout if needed */
 307         if (strncmp(&path[len], "/block/", 7) == 0) {
 308                 char block[UTIL_PATH_SIZE];
 309                 char part[UTIL_PATH_SIZE];
 310
 311                 util_strlcpy(block, path, sizeof(block));
 312                 pos = strrchr(block, '/');
 313                 if (pos == NULL)
 314                         return NULL;
 315                 util_strlcpy(part, pos, sizeof(part));
 316                 pos[0] = '\0';
 317                 if (util_resolve_sys_link(udev, block, sizeof(block)) == 0) {
 318                         util_strlcpy(path, block, sizeof(path));
 319                         util_strlcat(path, part, sizeof(path));
 320                 }
 321         }
 322
 323         /* path exists in sys */
 324         if (strncmp(&syspath[len], "/devices/", 9) == 0 ||
 325             strncmp(&syspath[len], "/class/", 7) == 0 ||
 326             strncmp(&syspath[len], "/block/", 7) == 0) {
 327                 char file[UTIL_PATH_SIZE];
 328
 329                 /* all "devices" require a "uevent" file */
 330                 util_strlcpy(file, path, sizeof(file));
 331                 util_strlcat(file, "/uevent", sizeof(file));
 332                 if (stat(file, &statbuf) != 0) {
 333                         info(udev, "not a device: %s\n", syspath);
 334                         return NULL;
 335                 }
 336         } else {
 337                 /* everything else just needs to be a directory */
 338                 if (stat(path, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) {
 339                         info(udev, "directory not found: %s\n", syspath);
 340                         return NULL;
 341                 }
 342         }
 343
 344         udev_device = device_new(udev);
 345         if (udev_device == NULL)
 346                 return NULL;
 347
 348         udev_device_set_syspath(udev_device, path);
 349         info(udev, "device %p has devpath '%s'\n", udev_device, udev_device_get_devpath(udev_device));
 350
 351         return udev_device;
 352 }
 353
 354 struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
 355 {
 356         char path[UTIL_PATH_SIZE];
 357         const char *type_str;
 358         struct udev_enumerate *udev_enumerate;
 359         struct udev_list_entry *list_entry;
 360         struct udev_device *device = NULL;
 361
 362         if (type == 'b')
 363                 type_str = "block";
 364         else if (type == 'c')
 365                 type_str = "char";
 366         else
 367                 return NULL;
 368
 369         /* /sys/dev/{block,char}/<maj>:<min> link */
 370         snprintf(path, sizeof(path), "%s/dev/%s/%u:%u", udev_get_sys_path(udev),
 371                  type_str, major(devnum), minor(devnum));
 372         if (util_resolve_sys_link(udev, path, sizeof(path)) == 0)
 373                 return udev_device_new_from_syspath(udev, path);
 374
 375         udev_enumerate = udev_enumerate_new(udev);
 376         if (udev_enumerate == NULL)
 377                 return NULL;
 378
 379         /* fallback to search sys devices for the major/minor */
 380         if (type == 'b')
 381                 udev_enumerate_add_match_subsystem(udev_enumerate, "block");
 382         else if (type == 'c')
 383                 udev_enumerate_add_nomatch_subsystem(udev_enumerate, "block");
 384         udev_enumerate_scan_devices(udev_enumerate);
 385         udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
 386                 struct udev_device *device_loop;
 387
 388                 device_loop = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
 389                 if (device_loop != NULL) {
 390                         if (udev_device_get_devnum(device_loop) == devnum) {
 391                                 if (type == 'b' && strcmp(udev_device_get_subsystem(device_loop), "block") != 0)
 392                                         continue;
 393                                 if (type == 'c' && strcmp(udev_device_get_subsystem(device_loop), "block") == 0)
 394                                         continue;
 395                                 device = device_loop;
 396                                 break;
 397                         }
 398                         udev_device_unref(device_loop);
 399                 }
 400         }
 401         udev_enumerate_unref(udev_enumerate);
 402         return device;
 403 }
 404
 405 struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
 406 {
 407         size_t sys_path_len;
 408         char path_full[UTIL_PATH_SIZE];
 409         char *path;
 410         struct stat statbuf;
 411
 412         sys_path_len = util_strlcpy(path_full, udev_get_sys_path(udev), sizeof(path_full));
 413         path = &path_full[sys_path_len];
 414
 415         if (strcmp(subsystem, "subsystem") == 0) {
 416                 util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
 417                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 418                 if (stat(path_full, &statbuf) == 0)
 419                         goto found;
 420
 421                 util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
 422                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 423                 if (stat(path_full, &statbuf) == 0)
 424                         goto found;
 425
 426                 util_strlcpy(path, "/class/", sizeof(path_full) - sys_path_len);
 427                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 428                 if (stat(path_full, &statbuf) == 0)
 429                         goto found;
 430                 goto out;
 431         }
 432
 433         if (strcmp(subsystem, "module") == 0) {
 434                 util_strlcpy(path, "/module/", sizeof(path_full) - sys_path_len);
 435                 util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 436                 if (stat(path_full, &statbuf) == 0)
 437                         goto found;
 438                 goto out;
 439         }
 440
 441         if (strcmp(subsystem, "drivers") == 0) {
 442                 char subsys[UTIL_NAME_SIZE];
 443                 char *driver;
 444
 445                 util_strlcpy(subsys, sysname, sizeof(subsys));
 446                 driver = strchr(subsys, ':');
 447                 if (driver != NULL) {
 448                         driver[0] = '\0';
 449                         driver = &driver[1];
 450                         util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
 451                         util_strlcat(path, subsys, sizeof(path_full) - sys_path_len);
 452                         util_strlcat(path, "/drivers/", sizeof(path_full) - sys_path_len);
 453                         util_strlcat(path, driver, sizeof(path_full) - sys_path_len);
 454                         if (stat(path_full, &statbuf) == 0)
 455                                 goto found;
 456
 457                         util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
 458                         util_strlcat(path, subsys, sizeof(path_full) - sys_path_len);
 459                         util_strlcat(path, "/drivers/", sizeof(path_full) - sys_path_len);
 460                         util_strlcat(path, driver, sizeof(path_full) - sys_path_len);
 461                         if (stat(path_full, &statbuf) == 0)
 462                                 goto found;
 463                 }
 464                 goto out;
 465         }
 466
 467         util_strlcpy(path, "/subsystem/", sizeof(path_full) - sys_path_len);
 468         util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
 469         util_strlcat(path, "/devices/", sizeof(path_full) - sys_path_len);
 470         util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 471         if (stat(path_full, &statbuf) == 0)
 472                 goto found;
 473
 474         util_strlcpy(path, "/bus/", sizeof(path_full) - sys_path_len);
 475         util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
 476         util_strlcat(path, "/devices/", sizeof(path_full) - sys_path_len);
 477         util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 478         if (stat(path_full, &statbuf) == 0)
 479                 goto found;
 480
 481         util_strlcpy(path, "/class/", sizeof(path_full) - sys_path_len);
 482         util_strlcat(path, subsystem, sizeof(path_full) - sys_path_len);
 483         util_strlcat(path, "/", sizeof(path_full) - sys_path_len);
 484         util_strlcat(path, sysname, sizeof(path_full) - sys_path_len);
 485         if (stat(path_full, &statbuf) == 0)
 486                 goto found;
 487 out:
 488         return NULL;
 489 found:
 490         return udev_device_new_from_syspath(udev, path_full);
 491 }
 492
 493 static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
 494 {
 495         struct udev_device *udev_device_parent = NULL;
 496         char path[UTIL_PATH_SIZE];
 497         const char *subdir;
 498
 499         /* follow "device" link in deprecated sys layout */
 500         if (strncmp(udev_device->devpath, "/class/", 7) == 0 ||
 501             strncmp(udev_device->devpath, "/block/", 7) == 0) {
 502                 util_strlcpy(path, udev_device->syspath, sizeof(path));
 503                 util_strlcat(path, "/device", sizeof(path));
 504                 if (util_resolve_sys_link(udev_device->udev, path, sizeof(path)) == 0)
 505                         udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
 506                 return udev_device_parent;
 507         }
 508
 509         util_strlcpy(path, udev_device->syspath, sizeof(path));
 510         subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
 511         while (1) {
 512                 char *pos;
 513
 514                 pos = strrchr(subdir, '/');
 515                 if (pos == NULL || pos < &subdir[2])
 516                         break;
 517                 pos[0] = '\0';
 518                 udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
 519                 if (udev_device_parent != NULL)
 520                         return udev_device_parent;
 521         }
 522         return NULL;
 523 }
 524
 525 struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
 526 {
 527         if (udev_device == NULL)
 528                 return NULL;
 529         if (!udev_device->parent_set) {
 530                 udev_device->parent_set = 1;
 531                 udev_device->parent_device = device_new_from_parent(udev_device);
 532         }
 533         if (udev_device->parent_device != NULL)
 534                 info(udev_device->udev, "returning existing parent %p\n", udev_device->parent_device);
 535         return udev_device->parent_device;
 536 }
 537
 538 struct udev_device *udev_device_get_parent_with_subsystem(struct udev_device *udev_device, const char *subsystem)
 539 {
 540         struct udev_device *parent;
 541
 542         parent = udev_device_get_parent(udev_device);
 543         while (parent != NULL) {
 544                 const char *parent_subsystem;
 545
 546                 parent_subsystem = udev_device_get_subsystem(parent);
 547                 if (parent_subsystem != NULL && strcmp(parent_subsystem, subsystem) == 0)
 548                         break;
 549                 parent = udev_device_get_parent(parent);
 550         }
 551         return parent;
 552 }
 553
 554 /**
 555  * udev_device_get_udev:
 556  * @udev_device: udev device
 557  *
 558  * Retrieve the udev library context the device was created with.
 559  *
 560  * Returns: the udev library context
 561  **/
 562 struct udev *udev_device_get_udev(struct udev_device *udev_device)
 563 {
 564         if (udev_device == NULL)
 565                 return NULL;
 566         return udev_device->udev;
 567 }
 568
 569 /**
 570  * udev_device_ref:
 571  * @udev_device: udev device
 572  *
 573  * Take a reference of a udev device.
 574  *
 575  * Returns: the passed udev device
 576  **/
 577 struct udev_device *udev_device_ref(struct udev_device *udev_device)
 578 {
 579         if (udev_device == NULL)
 580                 return NULL;
 581         udev_device->refcount++;
 582         return udev_device;
 583 }
 584
 585 /**
 586  * udev_device_unref:
 587  * @udev_device: udev device
 588  *
 589  * Drop a reference of a udev device. If the refcount reaches zero,
 590  * the ressources of the device will be released.
 591  *
 592  **/
 593 void udev_device_unref(struct udev_device *udev_device)
 594 {
 595         if (udev_device == NULL)
 596                 return;
 597         udev_device->refcount--;
 598         if (udev_device->refcount > 0)
 599                 return;
 600         if (udev_device->parent_device != NULL)
 601                 udev_device_unref(udev_device->parent_device);
 602         free(udev_device->syspath);
 603         free(udev_device->sysname);
 604         free(udev_device->devnode);
 605         free(udev_device->subsystem);
 606         udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
 607         udev_list_cleanup_entries(udev_device->udev, &udev_device->properties_list);
 608         free(udev_device->action);
 609         free(udev_device->driver);
 610         free(udev_device->devpath_old);
 611         free(udev_device->physdevpath);
 612         udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
 613         free(udev_device->envp);
 614         free(udev_device->monitor_buf);
 615         info(udev_device->udev, "udev_device: %p released\n", udev_device);
 616         free(udev_device);
 617 }
 618
 619 /**
 620  * udev_device_get_devpath:
 621  * @udev_device: udev device
 622  *
 623  * Retrieve the kernel devpath value of the udev device. The path
 624  * does not contain the sys mount point, and starts with a '/'.
 625  *
 626  * Returns: the devpath of the udev device
 627  **/
 628 const char *udev_device_get_devpath(struct udev_device *udev_device)
 629 {
 630         if (udev_device == NULL)
 631                 return NULL;
 632         return udev_device->devpath;
 633 }
 634
 635 /**
 636  * udev_device_get_syspath:
 637  * @udev_device: udev device
 638  *
 639  * Retrieve the sys path of the udev device. The path is an
 640  * absolute path and starts with the sys mount point.
 641  *
 642  * Returns: the sys path of the udev device
 643  **/
 644 const char *udev_device_get_syspath(struct udev_device *udev_device)
 645 {
 646         if (udev_device == NULL)
 647                 return NULL;
 648         return udev_device->syspath;
 649 }
 650
 651 const char *udev_device_get_sysname(struct udev_device *udev_device)
 652 {
 653         if (udev_device == NULL)
 654                 return NULL;
 655         return udev_device->sysname;
 656 }
 657
 658 const char *udev_device_get_sysnum(struct udev_device *udev_device)
 659 {
 660         if (udev_device == NULL)
 661                 return NULL;
 662         return udev_device->sysnum;
 663 }
 664
 665 /**
 666  * udev_device_get_devnode:
 667  * @udev_device: udev device
 668  *
 669  * Retrieve the device node file name belonging to the udev device.
 670  * The path is an absolute path, and starts with the device directory.
 671  *
 672  * Returns: the device node file name of the udev device, or #NULL if no device node exists
 673  **/
 674 const char *udev_device_get_devnode(struct udev_device *udev_device)
 675 {
 676         if (udev_device == NULL)
 677                 return NULL;
 678         if (!udev_device->info_loaded)
 679                 device_load_info(udev_device);
 680         return udev_device->devnode;
 681 }
 682
 683 /**
 684  * udev_device_get_subsystem:
 685  * @udev_device: udev device
 686  *
 687  * Retrieve the subsystem string of the udev device. The string does not
 688  * contain any "/".
 689  *
 690  * Returns: the subsystem name of the udev device, or #NULL if it can not be determined
 691  **/
 692 const char *udev_device_get_subsystem(struct udev_device *udev_device)
 693 {
 694         char subsystem[UTIL_NAME_SIZE];
 695
 696         if (udev_device == NULL)
 697                 return NULL;
 698         if (!udev_device->subsystem_set) {
 699                 udev_device->subsystem_set = 1;
 700                 /* read "subsytem" link */
 701                 if (util_get_sys_subsystem(udev_device->udev, udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
 702                         udev_device_set_subsystem(udev_device, subsystem);
 703                         return udev_device->subsystem;
 704                 }
 705                 /* implicit names */
 706                 if (strncmp(udev_device->devpath, "/module/", 8) == 0) {
 707                         udev_device_set_subsystem(udev_device, "module");
 708                         return udev_device->subsystem;
 709                 }
 710                 if (strstr(udev_device->devpath, "/drivers/") != NULL) {
 711                         udev_device_set_subsystem(udev_device, "drivers");
 712                         return udev_device->subsystem;
 713                 }
 714                 if (strncmp(udev_device->devpath, "/subsystem/", 11) == 0 ||
 715                     strncmp(udev_device->devpath, "/class/", 7) == 0 ||
 716                     strncmp(udev_device->devpath, "/bus/", 5) == 0) {
 717                         udev_device_set_subsystem(udev_device, "subsystem");
 718                         return udev_device->subsystem;
 719                 }
 720         }
 721         return udev_device->subsystem;
 722 }
 723
 724 /**
 725  * udev_device_get_devlinks_list_entry:
 726  * @udev_device: udev device
 727  *
 728  * Retrieve the list of device links pointing to the device file of
 729  * the udev device. The next list entry can be retrieved with
 730  * udev_list_entry_next(), which returns #NULL if no more entries exist.
 731  * The devlink path can be retrieved from the list entry by
 732  * udev_list_entry_get_name(). The path is an absolute path, and starts with
 733  * the device directory.
 734  *
 735  * Returns: the first entry of the device node link list
 736  **/
 737 struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device)
 738 {
 739         if (udev_device == NULL)
 740                 return NULL;
 741         if (!udev_device->info_loaded)
 742                 device_load_info(udev_device);
 743         return udev_list_get_entry(&udev_device->devlinks_list);
 744 }
 745
 746 void udev_device_cleanup_devlinks_list(struct udev_device *udev_device)
 747 {
 748         udev_device->devlinks_uptodate = 0;
 749         udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
 750 }
 751
 752 /**
 753  * udev_device_get_properties_list_entry:
 754  * @udev_device: udev device
 755  *
 756  * Retrieve the list of key/value device properties of the udev
 757  * device. The next list entry can be retrieved with udev_list_entry_next(),
 758  * which returns #NULL if no more entries exist. The property name
 759  * can be retrieved from the list entry by udev_list_get_name(),
 760  * the property value by udev_list_get_value().
 761  *
 762  * Returns: the first entry of the property list
 763  **/
 764 struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device)
 765 {
 766         if (udev_device == NULL)
 767                 return NULL;
 768         if (!udev_device->info_loaded)
 769                 device_load_info(udev_device);
 770         if (!udev_device->devlinks_uptodate) {
 771                 char symlinks[UTIL_PATH_SIZE];
 772                 struct udev_list_entry *list_entry;
 773
 774                 udev_device->devlinks_uptodate = 1;
 775                 list_entry = udev_device_get_devlinks_list_entry(udev_device);
 776                 if (list_entry != NULL) {
 777                         util_strlcpy(symlinks, udev_list_entry_get_name(list_entry), sizeof(symlinks));
 778                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry)) {
 779                                 util_strlcat(symlinks, " ", sizeof(symlinks));
 780                                 util_strlcat(symlinks, udev_list_entry_get_name(list_entry), sizeof(symlinks));
 781                         }
 782                         udev_device_add_property(udev_device, "DEVLINKS", symlinks);
 783                 }
 784         }
 785         return udev_list_get_entry(&udev_device->properties_list);
 786 }
 787
 788 const char *udev_device_get_driver(struct udev_device *udev_device)
 789 {
 790         char driver[UTIL_NAME_SIZE];
 791
 792         if (udev_device == NULL)
 793                 return NULL;
 794         if (!udev_device->driver_set) {
 795                 udev_device->driver_set = 1;
 796                 if (util_get_sys_driver(udev_device->udev, udev_device->syspath, driver, sizeof(driver)) > 0)
 797                         udev_device->driver = strdup(driver);
 798         }
 799         return udev_device->driver;
 800 }
 801
 802 dev_t udev_device_get_devnum(struct udev_device *udev_device)
 803 {
 804         if (udev_device == NULL)
 805                 return makedev(0, 0);
 806         if (!udev_device->info_loaded)
 807                 device_load_info(udev_device);
 808         return udev_device->devnum;
 809 }
 810
 811 const char *udev_device_get_action(struct udev_device *udev_device)
 812 {
 813         if (udev_device == NULL)
 814                 return NULL;
 815         return udev_device->action;
 816 }
 817
 818 unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
 819 {
 820         if (udev_device == NULL)
 821                 return 0;
 822         return udev_device->seqnum;
 823 }
 824
 825 const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
 826 {
 827         struct udev_list_entry *list_entry;
 828         char path[UTIL_PATH_SIZE];
 829         char value[UTIL_NAME_SIZE];
 830         struct stat statbuf;
 831         int fd;
 832         ssize_t size;
 833         const char *val = NULL;
 834
 835         if (udev_device == NULL)
 836                 return NULL;
 837         if (sysattr == NULL)
 838                 return NULL;
 839
 840         /* look for possibly already cached result */
 841         udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_device->sysattr_list)) {
 842                 if (strcmp(udev_list_entry_get_name(list_entry), sysattr) == 0) {
 843                         info(udev_device->udev, "got '%s' (%s) from cache\n",
 844                              sysattr, udev_list_entry_get_value(list_entry));
 845                         return udev_list_entry_get_value(list_entry);
 846                 }
 847         }
 848
 849         util_strlcpy(path, udev_device_get_syspath(udev_device), sizeof(path));
 850         util_strlcat(path, "/", sizeof(path));
 851         util_strlcat(path, sysattr, sizeof(path));
 852
 853         if (lstat(path, &statbuf) != 0) {
 854                 info(udev_device->udev, "no attribute '%s', keep negative entry\n", path);
 855                 udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, NULL, 0, 0);
 856                 goto out;
 857         }
 858
 859         if (S_ISLNK(statbuf.st_mode)) {
 860                 /* links return the last element of the target path */
 861                 char target[UTIL_NAME_SIZE];
 862                 int len;
 863                 char *pos;
 864
 865                 len = readlink(path, target, sizeof(target));
 866                 if (len > 0) {
 867                         target[len] = '\0';
 868                         pos = strrchr(target, '/');
 869                         if (pos != NULL) {
 870                                 pos = &pos[1];
 871                                 info(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, pos);
 872                                 list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, pos, 0, 0);
 873                                 val = udev_list_entry_get_value(list_entry);
 874                         }
 875                 }
 876                 goto out;
 877         }
 878
 879         /* skip directories */
 880         if (S_ISDIR(statbuf.st_mode))
 881                 goto out;
 882
 883         /* skip non-readable files */
 884         if ((statbuf.st_mode & S_IRUSR) == 0)
 885                 goto out;
 886
 887         /* read attribute value */
 888         fd = open(path, O_RDONLY);
 889         if (fd < 0) {
 890                 info(udev_device->udev, "attribute '%s' can not be opened\n", path);
 891                 goto out;
 892         }
 893         size = read(fd, value, sizeof(value));
 894         close(fd);
 895         if (size < 0)
 896                 goto out;
 897         if (size == sizeof(value))
 898                 goto out;
 899
 900         /* got a valid value, store it in cache and return it */
 901         value[size] = '\0';
 902         util_remove_trailing_chars(value, '\n');
 903         info(udev_device->udev, "'%s' has attribute value '%s'\n", path, value);
 904         list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, value, 0, 0);
 905         val = udev_list_entry_get_value(list_entry);
 906 out:
 907         return val;
 908 }
 909
 910 int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath)
 911 {
 912         const char *pos;
 913         size_t len;
 914
 915         free(udev_device->syspath);
 916         udev_device->syspath = strdup(syspath);
 917         if (udev_device->syspath ==  NULL)
 918                 return -ENOMEM;
 919         udev_device->devpath = &udev_device->syspath[strlen(udev_get_sys_path(udev_device->udev))];
 920         udev_device_add_property(udev_device, "DEVPATH", udev_device->devpath);
 921
 922         pos = strrchr(udev_device->syspath, '/');
 923         if (pos == NULL)
 924                 return -EINVAL;
 925         udev_device->sysname = strdup(&pos[1]);
 926         if (udev_device->sysname == NULL)
 927                 return -ENOMEM;
 928
 929         /* some devices have '!' in their name, change that to '/' */
 930         len = 0;
 931         while (udev_device->sysname[len] != '\0') {
 932                 if (udev_device->sysname[len] == '!')
 933                         udev_device->sysname[len] = '/';
 934                 len++;
 935         }
 936
 937         /* trailing number */
 938         while (len > 0 && isdigit(udev_device->sysname[--len]))
 939                 udev_device->sysnum = &udev_device->sysname[len];
 940
 941         /* sysname is completely numeric */
 942         if (len == 0)
 943                 udev_device->sysnum = NULL;
 944
 945         return 0;
 946 }
 947
 948 int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem)
 949 {
 950         free(udev_device->subsystem);
 951         udev_device->subsystem = strdup(subsystem);
 952         if (udev_device->subsystem == NULL)
 953                 return -ENOMEM;
 954         udev_device->subsystem_set = 1;
 955         udev_device_add_property(udev_device, "SUBSYSTEM", udev_device->subsystem);
 956         return 0;
 957 }
 958
 959 int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode)
 960 {
 961         free(udev_device->devnode);
 962         udev_device->devnode = strdup(devnode);
 963         if (devnode == NULL)
 964                 return 0;
 965         if (udev_device->devnode == NULL)
 966                 return -ENOMEM;
 967         udev_device_add_property(udev_device, "DEVNAME", udev_device->devnode);
 968         return 0;
 969 }
 970
 971 int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink)
 972 {
 973         udev_device->devlinks_uptodate = 0;
 974         if (udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, 1, 0) == NULL)
 975                 return -ENOMEM;
 976         return 0;
 977 }
 978
 979 struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
 980 {
 981         udev_device->envp_uptodate = 0;
 982         if (value == NULL) {
 983                 struct udev_list_entry *list_entry;
 984
 985                 list_entry = udev_device_get_properties_list_entry(udev_device);
 986                 list_entry = udev_list_entry_get_by_name(list_entry, key);
 987                 if (list_entry != NULL)
 988                         udev_list_entry_remove(list_entry);
 989                 return NULL;
 990         }
 991         return udev_list_entry_add(udev_device->udev, &udev_device->properties_list, key, value, 1, 0);
 992 }
 993
 994 struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
 995 {
 996         char name[UTIL_PATH_SIZE];
 997         char *val;
 998
 999         util_strlcpy(name, property, sizeof(name));
1000         val = strchr(name, '=');
1001         if (val == NULL)
1002                 return NULL;
1003         val[0] = '\0';
1004         val = &val[1];
1005         if (val[0] == '\0')
1006                 val = NULL;
1007         return udev_device_add_property(udev_device, name, val);
1008 }
1009
1010 #define ENVP_SIZE                       128
1011 #define MONITOR_BUF_SIZE                4096
1012 static int update_envp_monitor_buf(struct udev_device *udev_device)
1013 {
1014         const char *action;
1015         struct udev_list_entry *list_entry;
1016         size_t bufpos;
1017         size_t len;
1018         unsigned int i;
1019
1020         /* monitor buffer of property strings */
1021         free(udev_device->monitor_buf);
1022         udev_device->monitor_buf_len = 0;
1023         udev_device->monitor_buf = malloc(MONITOR_BUF_SIZE);
1024         if (udev_device->monitor_buf == NULL)
1025                 return -ENOMEM;
1026
1027         /* envp array, strings will point into monitor buffer */
1028         free(udev_device->envp);
1029         udev_device->envp = malloc(sizeof(char *) * ENVP_SIZE);
1030         if (udev_device->envp == NULL)
1031                 return -ENOMEM;
1032
1033         /* header <action>@<devpath> */
1034         action = udev_device_get_action(udev_device);
1035         if (action == NULL)
1036                 return -EINVAL;
1037         bufpos = util_strlcpy(udev_device->monitor_buf, action, MONITOR_BUF_SIZE);
1038         len = util_strlcpy(&udev_device->monitor_buf[bufpos], "@", MONITOR_BUF_SIZE-bufpos);
1039         if (len >= MONITOR_BUF_SIZE-bufpos)
1040                 return -EINVAL;
1041         bufpos += len;
1042         len = util_strlcpy(&udev_device->monitor_buf[bufpos],
1043                            udev_device_get_devpath(udev_device),
1044                            MONITOR_BUF_SIZE-bufpos);
1045         if (len+1 >= MONITOR_BUF_SIZE-bufpos)
1046                 return -EINVAL;
1047         bufpos += len+1;
1048
1049         i = 0;
1050         udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
1051                 /* add string to envp array */
1052                 udev_device->envp[i++] = &udev_device->monitor_buf[bufpos];
1053                 if (i+1 >= ENVP_SIZE)
1054                         return -EINVAL;
1055
1056                 /* add property string to monitor buffer */
1057                 len = util_strlcpy(&udev_device->monitor_buf[bufpos],
1058                                    udev_list_entry_get_name(list_entry), MONITOR_BUF_SIZE-bufpos);
1059                 if (len >= MONITOR_BUF_SIZE-bufpos)
1060                         return -EINVAL;
1061                 bufpos += len;
1062                 len = util_strlcpy(&udev_device->monitor_buf[bufpos], "=", MONITOR_BUF_SIZE-bufpos);
1063                 if (len >= MONITOR_BUF_SIZE-bufpos)
1064                         return -EINVAL;
1065                 bufpos += len;
1066                 len = util_strlcpy(&udev_device->monitor_buf[bufpos], udev_list_entry_get_value(list_entry),
1067                                    MONITOR_BUF_SIZE-bufpos);
1068                 if (len+1 >= MONITOR_BUF_SIZE-bufpos)
1069                         return -EINVAL;
1070                 bufpos += len+1;
1071         }
1072         udev_device->envp[i] = NULL;
1073         udev_device->monitor_buf_len = bufpos;
1074         udev_device->envp_uptodate = 1;
1075         info(udev_device->udev, "filled envp/monitor buffer, %u properties, %zu bytes\n", i, bufpos);
1076         return 0;
1077 }
1078
1079 char **udev_device_get_properties_envp(struct udev_device *udev_device)
1080 {
1081         if (!udev_device->envp_uptodate)
1082                 if (update_envp_monitor_buf(udev_device) != 0)
1083                         return NULL;
1084         return udev_device->envp;
1085 }
1086
1087 ssize_t udev_device_get_properties_monitor_buf(struct udev_device *udev_device, const char **buf)
1088 {
1089         if (!udev_device->envp_uptodate)
1090                 if (update_envp_monitor_buf(udev_device) != 0)
1091                         return -EINVAL;
1092         *buf = udev_device->monitor_buf;
1093         return udev_device->monitor_buf_len;
1094 }
1095
1096 int udev_device_set_action(struct udev_device *udev_device, const char *action)
1097 {
1098         free(udev_device->action);
1099         udev_device->action = strdup(action);
1100         if (udev_device->action == NULL)
1101                 return -ENOMEM;
1102         udev_device_add_property(udev_device, "ACTION", udev_device->action);
1103         return 0;
1104 }
1105
1106 int udev_device_set_driver(struct udev_device *udev_device, const char *driver)
1107 {
1108         free(udev_device->driver);
1109         udev_device->driver = strdup(driver);
1110         if (udev_device->driver == NULL)
1111                 return -ENOMEM;
1112         udev_device->driver_set = 1;
1113         udev_device_add_property(udev_device, "DRIVER", udev_device->driver);
1114         return 0;
1115 }
1116
1117 const char *udev_device_get_devpath_old(struct udev_device *udev_device)
1118 {
1119         return udev_device->devpath_old;
1120 }
1121
1122 int udev_device_set_devpath_old(struct udev_device *udev_device, const char *devpath_old)
1123 {
1124         udev_device->devpath_old = strdup(devpath_old);
1125         if (udev_device->devpath_old == NULL)
1126                 return -ENOMEM;
1127         udev_device_add_property(udev_device, "DEVPATH_OLD", udev_device->devpath_old);
1128         return 0;
1129 }
1130
1131 const char *udev_device_get_physdevpath(struct udev_device *udev_device)
1132 {
1133         return udev_device->physdevpath;
1134 }
1135
1136 int udev_device_set_physdevpath(struct udev_device *udev_device, const char *physdevpath)
1137 {
1138         udev_device->physdevpath = strdup(physdevpath);
1139         if (udev_device->physdevpath == NULL)
1140                 return -ENOMEM;
1141         return 0;
1142 }
1143
1144 int udev_device_get_timeout(struct udev_device *udev_device)
1145 {
1146         return udev_device->timeout;
1147 }
1148
1149 int udev_device_set_timeout(struct udev_device *udev_device, int timeout)
1150 {
1151         udev_device->timeout = timeout;
1152         return 0;
1153 }
1154 int udev_device_get_event_timeout(struct udev_device *udev_device)
1155 {
1156         if (!udev_device->info_loaded)
1157                 device_load_info(udev_device);
1158         return udev_device->event_timeout;
1159 }
1160
1161 int udev_device_set_event_timeout(struct udev_device *udev_device, int event_timeout)
1162 {
1163         udev_device->event_timeout = event_timeout;
1164         return 0;
1165 }
1166
1167 int udev_device_set_seqnum(struct udev_device *udev_device, unsigned long long int seqnum)
1168 {
1169         char num[32];
1170
1171         udev_device->seqnum = seqnum;
1172         snprintf(num, sizeof(num), "%llu", seqnum);
1173         udev_device_add_property(udev_device, "SEQNUM", num);
1174         return 0;
1175 }
1176
1177 int udev_device_set_devnum(struct udev_device *udev_device, dev_t devnum)
1178 {
1179         char num[32];
1180
1181         udev_device->devnum = devnum;
1182
1183         snprintf(num, sizeof(num), "%u", major(devnum));
1184         udev_device_add_property(udev_device, "MAJOR", num);
1185         snprintf(num, sizeof(num), "%u", minor(devnum));
1186         udev_device_add_property(udev_device, "MINOR", num);
1187         return 0;
1188 }
1189
1190 int udev_device_get_num_fake_partitions(struct udev_device *udev_device)
1191 {
1192         if (!udev_device->info_loaded)
1193                 device_load_info(udev_device);
1194         return udev_device->num_fake_partitions;
1195 }
1196
1197 int udev_device_set_num_fake_partitions(struct udev_device *udev_device, int num)
1198 {
1199         udev_device->num_fake_partitions = num;
1200         return 0;
1201 }
1202
1203 int udev_device_get_devlink_priority(struct udev_device *udev_device)
1204 {
1205         if (!udev_device->info_loaded)
1206                 device_load_info(udev_device);
1207         return udev_device->devlink_priority;
1208 }
1209
1210 int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio)
1211 {
1212          udev_device->devlink_priority = prio;
1213         return 0;
1214 }
1215
1216 int udev_device_get_ignore_remove(struct udev_device *udev_device)
1217 {
1218         if (!udev_device->info_loaded)
1219                 device_load_info(udev_device);
1220         return udev_device->ignore_remove;
1221 }
1222
1223 int udev_device_set_ignore_remove(struct udev_device *udev_device, int ignore)
1224 {
1225         udev_device->ignore_remove = ignore;
1226         return 0;
1227 }