libudev/libudev-device.c

   1 /*
   2  * libudev - interface to udev device information
   3  *
   4  * Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <stddef.h>
  15 #include <unistd.h>
  16 #include <stdbool.h>
  17 #include <errno.h>
  18 #include <string.h>
  19 #include <dirent.h>
  20 #include <fcntl.h>
  21 #include <ctype.h>
  22 #include <sys/stat.h>
  23
  24 #include "libudev.h"
  25 #include "libudev-private.h"
  26
  27 /**
  28  * SECTION:libudev-device
  29  * @short_description: kernel sys devices
  30  *
  31  * Representation of kernel sys devices. Devices are uniquely identified
  32  * by their syspath, every device has exactly one path in the kernel sys
  33  * filesystem. Devices usually belong to a kernel subsystem, and and have
  34  * a unique name inside that subsystem.
  35  */
  36
  37 /**
  38  * udev_device:
  39  *
  40  * Opaque object representing one kernel sys device.
  41  */
  42 struct udev_device {
  43         struct udev *udev;
  44         struct udev_device *parent_device;
  45         char *syspath;
  46         const char *devpath;
  47         char *sysname;
  48         const char *sysnum;
  49         char *devnode;
  50         char *subsystem;
  51         char *devtype;
  52         char *driver;
  53         char *action;
  54         char *devpath_old;
  55         char *sysname_old;
  56         char *knodename;
  57         char **envp;
  58         char *monitor_buf;
  59         size_t monitor_buf_len;
  60         struct udev_list_node devlinks_list;
  61         struct udev_list_node properties_list;
  62         struct udev_list_node sysattr_list;
  63         struct udev_list_node tags_list;
  64         unsigned long long int seqnum;
  65         int event_timeout;
  66         int timeout;
  67         int devlink_priority;
  68         int refcount;
  69         dev_t devnum;
  70         int watch_handle;
  71         int maj, min;
  72         bool parent_set;
  73         bool subsystem_set;
  74         bool devtype_set;
  75         bool devlinks_uptodate;
  76         bool envp_uptodate;
  77         bool tags_uptodate;
  78         bool driver_set;
  79         bool info_loaded;
  80         bool db_loaded;
  81         bool uevent_loaded;
  82 };
  83
  84 struct udev_list_entry *udev_device_add_property(struct udev_device *udev_device, const char *key, const char *value)
  85 {
  86         udev_device->envp_uptodate = false;
  87         if (value == NULL) {
  88                 struct udev_list_entry *list_entry;
  89
  90                 list_entry = udev_device_get_properties_list_entry(udev_device);
  91                 list_entry = udev_list_entry_get_by_name(list_entry, key);
  92                 if (list_entry != NULL)
  93                         udev_list_entry_delete(list_entry);
  94                 return NULL;
  95         }
  96         return udev_list_entry_add(udev_device->udev, &udev_device->properties_list, key, value, 1, 0);
  97 }
  98
  99 static struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
 100 {
 101         char name[UTIL_LINE_SIZE];
 102         char *val;
 103
 104         util_strscpy(name, sizeof(name), property);
 105         val = strchr(name, '=');
 106         if (val == NULL)
 107                 return NULL;
 108         val[0] = '\0';
 109         val = &val[1];
 110         if (val[0] == '\0')
 111                 val = NULL;
 112         return udev_device_add_property(udev_device, name, val);
 113 }
 114
 115 /*
 116  * parse property string, and if needed, update internal values accordingly
 117  *
 118  * udev_device_add_property_from_string_parse_finish() needs to be
 119  * called after adding properties, and its return value checked
 120  *
 121  * udev_device_set_info_loaded() needs to be set, to avoid trying
 122  * to use a device without a DEVPATH set
 123  */
 124 void udev_device_add_property_from_string_parse(struct udev_device *udev_device, const char *property)
 125 {
 126         if (strncmp(property, "DEVPATH=", 8) == 0) {
 127                 char path[UTIL_PATH_SIZE];
 128
 129                 util_strscpyl(path, sizeof(path), udev_get_sys_path(udev_device->udev), &property[8], NULL);
 130                 udev_device_set_syspath(udev_device, path);
 131         } else if (strncmp(property, "SUBSYSTEM=", 10) == 0) {
 132                 udev_device_set_subsystem(udev_device, &property[10]);
 133         } else if (strncmp(property, "DEVTYPE=", 8) == 0) {
 134                 udev_device_set_devtype(udev_device, &property[8]);
 135         } else if (strncmp(property, "DEVNAME=", 8) == 0) {
 136                 if (property[8] == '/')
 137                         udev_device_set_devnode(udev_device, &property[8]);
 138                 else
 139                         udev_device_set_knodename(udev_device, &property[8]);
 140         } else if (strncmp(property, "DEVLINKS=", 9) == 0) {
 141                 char devlinks[UTIL_PATH_SIZE];
 142                 char *slink;
 143                 char *next;
 144
 145                 util_strscpy(devlinks, sizeof(devlinks), &property[9]);
 146                 slink = devlinks;
 147                 next = strchr(slink, ' ');
 148                 while (next != NULL) {
 149                         next[0] = '\0';
 150                         udev_device_add_devlink(udev_device, slink, 0);
 151                         slink = &next[1];
 152                         next = strchr(slink, ' ');
 153                 }
 154                 if (slink[0] != '\0')
 155                         udev_device_add_devlink(udev_device, slink, 0);
 156         } else if (strncmp(property, "TAGS=", 5) == 0) {
 157                 char tags[UTIL_PATH_SIZE];
 158                 char *next;
 159
 160                 util_strscpy(tags, sizeof(tags), &property[5]);
 161                 next = strchr(tags, ':');
 162                 if (next != NULL) {
 163                         next++;
 164                         while (next[0] != '\0') {
 165                                 char *tag;
 166
 167                                 tag = next;
 168                                 next = strchr(tag, ':');
 169                                 if (next == NULL)
 170                                         break;
 171                                 next[0] = '\0';
 172                                 next++;
 173                                 udev_device_add_tag(udev_device, tag);
 174                         }
 175                 }
 176         } else if (strncmp(property, "DRIVER=", 7) == 0) {
 177                 udev_device_set_driver(udev_device, &property[7]);
 178         } else if (strncmp(property, "ACTION=", 7) == 0) {
 179                 udev_device_set_action(udev_device, &property[7]);
 180         } else if (strncmp(property, "MAJOR=", 6) == 0) {
 181                 udev_device->maj = strtoull(&property[6], NULL, 10);
 182         } else if (strncmp(property, "MINOR=", 6) == 0) {
 183                 udev_device->min = strtoull(&property[6], NULL, 10);
 184         } else if (strncmp(property, "DEVPATH_OLD=", 12) == 0) {
 185                 udev_device_set_devpath_old(udev_device, &property[12]);
 186         } else if (strncmp(property, "SEQNUM=", 7) == 0) {
 187                 udev_device_set_seqnum(udev_device, strtoull(&property[7], NULL, 10));
 188         } else if (strncmp(property, "TIMEOUT=", 8) == 0) {
 189                 udev_device_set_timeout(udev_device, strtoull(&property[8], NULL, 10));
 190         } else {
 191                 udev_device_add_property_from_string(udev_device, property);
 192         }
 193 }
 194
 195 int udev_device_add_property_from_string_parse_finish(struct udev_device *udev_device)
 196 {
 197         if (udev_device->maj > 0)
 198                 udev_device_set_devnum(udev_device, makedev(udev_device->maj, udev_device->min));
 199         udev_device->maj = 0;
 200         udev_device->min = 0;
 201
 202         if (udev_device->devpath == NULL || udev_device->subsystem == NULL)
 203                 return -EINVAL;
 204         return 0;
 205 }
 206
 207 /**
 208  * udev_device_get_property_value:
 209  * @udev_device: udev device
 210  * @key: property name
 211  *
 212  * Returns: the value of a device property, or #NULL if there is no such property.
 213  **/
 214 const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key)
 215 {
 216         struct udev_list_entry *list_entry;
 217
 218         if (udev_device == NULL)
 219                 return NULL;
 220         if (key == NULL)
 221                 return NULL;
 222
 223         list_entry = udev_device_get_properties_list_entry(udev_device);
 224         list_entry =  udev_list_entry_get_by_name(list_entry, key);
 225         return udev_list_entry_get_value(list_entry);
 226 }
 227
 228 int udev_device_read_db(struct udev_device *udev_device)
 229 {
 230         struct stat stats;
 231         char filename[UTIL_PATH_SIZE];
 232         char line[UTIL_LINE_SIZE];
 233         FILE *f;
 234
 235         if (udev_device->db_loaded)
 236                 return 0;
 237
 238         util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/.udev/db/",
 239                       udev_device_get_subsystem(udev_device), ":", udev_device_get_sysname(udev_device), NULL);
 240
 241         if (lstat(filename, &stats) != 0) {
 242                 dbg(udev_device->udev, "no db file to read %s: %m\n", filename);
 243                 return -1;
 244         }
 245         if ((stats.st_mode & S_IFMT) == S_IFLNK) {
 246                 char target[UTIL_PATH_SIZE];
 247                 char devnode[UTIL_PATH_SIZE];
 248                 int target_len;
 249                 char *next;
 250
 251                 target_len = readlink(filename, target, sizeof(target));
 252                 if (target_len <= 0 || target_len == sizeof(target)) {
 253                         info(udev_device->udev, "error reading db link %s: %m\n", filename);
 254                         return -1;
 255                 }
 256                 target[target_len] = '\0';
 257
 258                 next = strchr(target, ' ');
 259                 if (next != NULL) {
 260                         next[0] = '\0';
 261                         next = &next[1];
 262                 }
 263                 util_strscpyl(devnode, sizeof(devnode), udev_get_dev_path(udev_device->udev), "/", target, NULL);
 264                 udev_device_set_devnode(udev_device, devnode);
 265                 while (next != NULL) {
 266                         char devlink[UTIL_PATH_SIZE];
 267                         const char *lnk;
 268
 269                         lnk = next;
 270                         next = strchr(next, ' ');
 271                         if (next != NULL) {
 272                                 next[0] = '\0';
 273                                 next = &next[1];
 274                         }
 275                         util_strscpyl(devlink, sizeof(devlink), udev_get_dev_path(udev_device->udev), "/", lnk, NULL);
 276                         udev_device_add_devlink(udev_device, devlink, 0);
 277                 }
 278                 info(udev_device->udev, "device %p filled with db symlink data '%s'\n", udev_device, udev_device->devnode);
 279                 return 0;
 280         }
 281
 282         f = fopen(filename, "re");
 283         if (f == NULL) {
 284                 dbg(udev_device->udev, "error reading db file %s: %m\n", filename);
 285                 return -1;
 286         }
 287         udev_device->db_loaded = true;
 288
 289         while (fgets(line, sizeof(line), f)) {
 290                 ssize_t len;
 291                 const char *val;
 292
 293                 len = strlen(line);
 294                 if (len < 4)
 295                         break;
 296                 line[len-1] = '\0';
 297                 val = &line[2];
 298                 switch(line[0]) {
 299                 case 'N':
 300                         util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/", val, NULL);
 301                         udev_device_set_devnode(udev_device, filename);
 302                         break;
 303                 case 'S':
 304                         util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/", val, NULL);
 305                         udev_device_add_devlink(udev_device, filename, 0);
 306                         break;
 307                 case 'L':
 308                         udev_device_set_devlink_priority(udev_device, atoi(val));
 309                         break;
 310                 case 'T':
 311                         udev_device_set_event_timeout(udev_device, atoi(val));
 312                         break;
 313                 case 'E':
 314                         udev_device_add_property_from_string(udev_device, val);
 315                         break;
 316                 case 'G':
 317                         udev_device_add_tag(udev_device, val);
 318                         break;
 319                 case 'W':
 320                         udev_device_set_watch_handle(udev_device, atoi(val));
 321                         break;
 322                 }
 323         }
 324         fclose(f);
 325
 326         info(udev_device->udev, "device %p filled with db file data\n", udev_device);
 327         return 0;
 328 }
 329
 330 int udev_device_read_uevent_file(struct udev_device *udev_device)
 331 {
 332         char filename[UTIL_PATH_SIZE];
 333         FILE *f;
 334         char line[UTIL_LINE_SIZE];
 335         int maj = 0;
 336         int min = 0;
 337
 338         if (udev_device->uevent_loaded)
 339                 return 0;
 340
 341         util_strscpyl(filename, sizeof(filename), udev_device->syspath, "/uevent", NULL);
 342         f = fopen(filename, "re");
 343         if (f == NULL)
 344                 return -1;
 345         udev_device->uevent_loaded = true;
 346
 347         while (fgets(line, sizeof(line), f)) {
 348                 char *pos;
 349
 350                 pos = strchr(line, '\n');
 351                 if (pos == NULL)
 352                         continue;
 353                 pos[0] = '\0';
 354
 355                 if (strncmp(line, "DEVTYPE=", 8) == 0)
 356                         udev_device_set_devtype(udev_device, &line[8]);
 357                 else if (strncmp(line, "MAJOR=", 6) == 0)
 358                         maj = strtoull(&line[6], NULL, 10);
 359                 else if (strncmp(line, "MINOR=", 6) == 0)
 360                         min = strtoull(&line[6], NULL, 10);
 361                 else if (strncmp(line, "DEVNAME=", 8) == 0)
 362                         udev_device_set_knodename(udev_device, &line[8]);
 363
 364                 udev_device_add_property_from_string(udev_device, line);
 365         }
 366
 367         udev_device->devnum = makedev(maj, min);
 368         fclose(f);
 369         return 0;
 370 }
 371
 372 void udev_device_set_info_loaded(struct udev_device *device)
 373 {
 374         device->info_loaded = true;
 375 }
 376
 377 struct udev_device *udev_device_new(struct udev *udev)
 378 {
 379         struct udev_device *udev_device;
 380         struct udev_list_entry *list_entry;
 381
 382         if (udev == NULL)
 383                 return NULL;
 384
 385         udev_device = calloc(1, sizeof(struct udev_device));
 386         if (udev_device == NULL)
 387                 return NULL;
 388         udev_device->refcount = 1;
 389         udev_device->udev = udev;
 390         udev_list_init(&udev_device->devlinks_list);
 391         udev_list_init(&udev_device->properties_list);
 392         udev_list_init(&udev_device->sysattr_list);
 393         udev_list_init(&udev_device->tags_list);
 394         udev_device->event_timeout = -1;
 395         udev_device->watch_handle = -1;
 396         /* copy global properties */
 397         udev_list_entry_foreach(list_entry, udev_get_properties_list_entry(udev))
 398                 udev_device_add_property(udev_device,
 399                                          udev_list_entry_get_name(list_entry),
 400                                          udev_list_entry_get_value(list_entry));
 401         dbg(udev_device->udev, "udev_device: %p created\n", udev_device);
 402         return udev_device;
 403 }
 404
 405 /**
 406  * udev_device_new_from_syspath:
 407  * @udev: udev library context
 408  * @syspath: sys device path including sys directory
 409  *
 410  * Create new udev device, and fill in information from the sys
 411  * device and the udev database entry. The syspath is the absolute
 412  * path to the device, including the sys mount point.
 413  *
 414  * The initial refcount is 1, and needs to be decremented to
 415  * release the resources of the udev device.
 416  *
 417  * Returns: a new udev device, or #NULL, if it does not exist
 418  **/
 419 struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *syspath)
 420 {
 421         size_t len;
 422         const char *subdir;
 423         char path[UTIL_PATH_SIZE];
 424         char *pos;
 425         struct stat statbuf;
 426         struct udev_device *udev_device;
 427
 428         if (udev == NULL)
 429                 return NULL;
 430         if (syspath == NULL)
 431                 return NULL;
 432
 433         /* path starts in sys */
 434         len = strlen(udev_get_sys_path(udev));
 435         if (strncmp(syspath, udev_get_sys_path(udev), len) != 0) {
 436                 info(udev, "not in sys :%s\n", syspath);
 437                 return NULL;
 438         }
 439
 440         /* path is not a root directory */
 441         subdir = &syspath[len+1];
 442         pos = strrchr(subdir, '/');
 443         if (pos == NULL || pos[1] == '\0' || pos < &subdir[2]) {
 444                 dbg(udev, "not a subdir :%s\n", syspath);
 445                 return NULL;
 446         }
 447
 448         /* resolve possible symlink to real path */
 449         util_strscpy(path, sizeof(path), syspath);
 450         util_resolve_sys_link(udev, path, sizeof(path));
 451
 452         if (strncmp(&path[len], "/devices/", 9) == 0) {
 453                 char file[UTIL_PATH_SIZE];
 454
 455                 /* all "devices" require a "uevent" file */
 456                 util_strscpyl(file, sizeof(file), path, "/uevent", NULL);
 457                 if (stat(file, &statbuf) != 0) {
 458                         dbg(udev, "not a device: %s\n", syspath);
 459                         return NULL;
 460                 }
 461         } else {
 462                 /* everything else just needs to be a directory */
 463                 if (stat(path, &statbuf) != 0 || !S_ISDIR(statbuf.st_mode)) {
 464                         dbg(udev, "directory not found: %s\n", syspath);
 465                         return NULL;
 466                 }
 467         }
 468
 469         udev_device = udev_device_new(udev);
 470         if (udev_device == NULL)
 471                 return NULL;
 472
 473         udev_device_set_syspath(udev_device, path);
 474         info(udev, "device %p has devpath '%s'\n", udev_device, udev_device_get_devpath(udev_device));
 475
 476         return udev_device;
 477 }
 478
 479 /**
 480  * udev_device_new_from_devnum:
 481  * @udev: udev library context
 482  * @type: char or block device
 483  * @devnum: device major/minor number
 484  *
 485  * Create new udev device, and fill in information from the sys
 486  * device and the udev database entry. The device is looked-up
 487  * by its major/minor number and type. Character and block device
 488  * numbers are not unique across the two types.
 489  *
 490  * The initial refcount is 1, and needs to be decremented to
 491  * release the resources of the udev device.
 492  *
 493  * Returns: a new udev device, or #NULL, if it does not exist
 494  **/
 495 struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
 496 {
 497         char path[UTIL_PATH_SIZE];
 498         const char *type_str;
 499
 500         if (type == 'b')
 501                 type_str = "block";
 502         else if (type == 'c')
 503                 type_str = "char";
 504         else
 505                 return NULL;
 506
 507         /* use /sys/dev/{block,char}/<maj>:<min> link */
 508         snprintf(path, sizeof(path), "%s/dev/%s/%u:%u",
 509                  udev_get_sys_path(udev), type_str, major(devnum), minor(devnum));
 510         return udev_device_new_from_syspath(udev, path);
 511 }
 512
 513 /**
 514  * udev_device_new_from_subsystem_sysname:
 515  * @udev: udev library context
 516  * @subsystem: the subsystem of the device
 517  * @sysname: the name of the device
 518  *
 519  * Create new udev device, and fill in information from the sys device
 520  * and the udev database entry. The device is looked up by the subsystem
 521  * and name string of the device, like "mem" / "zero", or "block" / "sda".
 522  *
 523  * The initial refcount is 1, and needs to be decremented to
 524  * release the resources of the udev device.
 525  *
 526  * Returns: a new udev device, or #NULL, if it does not exist
 527  **/
 528 struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
 529 {
 530         char path_full[UTIL_PATH_SIZE];
 531         char *path;
 532         size_t l;
 533         struct stat statbuf;
 534
 535         path = path_full;
 536         l = util_strpcpyl(&path, sizeof(path_full), udev_get_sys_path(udev), NULL);
 537
 538         if (strcmp(subsystem, "subsystem") == 0) {
 539                 util_strscpyl(path, l, "/subsystem/", sysname, NULL);
 540                 if (stat(path_full, &statbuf) == 0)
 541                         goto found;
 542
 543                 util_strscpyl(path, l, "/bus/", sysname, NULL);
 544                 if (stat(path_full, &statbuf) == 0)
 545                         goto found;
 546
 547                 util_strscpyl(path, l, "/class/", sysname, NULL);
 548                 if (stat(path_full, &statbuf) == 0)
 549                         goto found;
 550                 goto out;
 551         }
 552
 553         if (strcmp(subsystem, "module") == 0) {
 554                 util_strscpyl(path, l, "/module/", sysname, NULL);
 555                 if (stat(path_full, &statbuf) == 0)
 556                         goto found;
 557                 goto out;
 558         }
 559
 560         if (strcmp(subsystem, "drivers") == 0) {
 561                 char subsys[UTIL_NAME_SIZE];
 562                 char *driver;
 563
 564                 util_strscpy(subsys, sizeof(subsys), sysname);
 565                 driver = strchr(subsys, ':');
 566                 if (driver != NULL) {
 567                         driver[0] = '\0';
 568                         driver = &driver[1];
 569
 570                         util_strscpyl(path, l, "/subsystem/", subsys, "/drivers/", driver, NULL);
 571                         if (stat(path_full, &statbuf) == 0)
 572                                 goto found;
 573
 574                         util_strscpyl(path, l, "/bus/", subsys, "/drivers/", driver, NULL);
 575                         if (stat(path_full, &statbuf) == 0)
 576                                 goto found;
 577                 }
 578                 goto out;
 579         }
 580
 581         util_strscpyl(path, l, "/subsystem/", subsystem, "/devices/", sysname, NULL);
 582         if (stat(path_full, &statbuf) == 0)
 583                 goto found;
 584
 585         util_strscpyl(path, l, "/bus/", subsystem, "/devices/", sysname, NULL);
 586         if (stat(path_full, &statbuf) == 0)
 587                 goto found;
 588
 589         util_strscpyl(path, l, "/class/", subsystem, "/", sysname, NULL);
 590         if (stat(path_full, &statbuf) == 0)
 591                 goto found;
 592 out:
 593         return NULL;
 594 found:
 595         return udev_device_new_from_syspath(udev, path_full);
 596 }
 597
 598 /**
 599  * udev_device_new_from_environment
 600  * @udev: udev library context
 601  *
 602  * Create new udev device, and fill in information from the
 603  * current process environment. This only works reliable if
 604  * the process is called from a udev rule. It is usually used
 605  * for tools executed from IMPORT= rules.
 606  *
 607  * The initial refcount is 1, and needs to be decremented to
 608  * release the resources of the udev device.
 609  *
 610  * Returns: a new udev device, or #NULL, if it does not exist
 611  **/
 612 struct udev_device *udev_device_new_from_environment(struct udev *udev)
 613 {
 614         int i;
 615         struct udev_device *udev_device;
 616
 617         udev_device = udev_device_new(udev);
 618         if (udev_device == NULL)
 619                 return NULL;
 620         udev_device_set_info_loaded(udev_device);
 621
 622         for (i = 0; environ[i] != NULL; i++)
 623                 udev_device_add_property_from_string_parse(udev_device, environ[i]);
 624
 625         if (udev_device_add_property_from_string_parse_finish(udev_device) < 0) {
 626                 info(udev, "missing values, invalid device\n");
 627                 udev_device_unref(udev_device);
 628                 udev_device = NULL;
 629         }
 630
 631         return udev_device;
 632 }
 633
 634 static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
 635 {
 636         struct udev_device *udev_device_parent = NULL;
 637         char path[UTIL_PATH_SIZE];
 638         const char *subdir;
 639
 640         util_strscpy(path, sizeof(path), udev_device->syspath);
 641         subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
 642         for (;;) {
 643                 char *pos;
 644
 645                 pos = strrchr(subdir, '/');
 646                 if (pos == NULL || pos < &subdir[2])
 647                         break;
 648                 pos[0] = '\0';
 649                 udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
 650                 if (udev_device_parent != NULL)
 651                         return udev_device_parent;
 652         }
 653         return NULL;
 654 }
 655
 656 /**
 657  * udev_device_get_parent:
 658  * @udev_device: the device to start searching from
 659  *
 660  * Find the next parent device, and fill in information from the sys
 661  * device and the udev database entry.
 662  *
 663  * The returned the device is not referenced. It is attached to the
 664  * child device, and will be cleaned up when the child device
 665  * is cleaned up.
 666  *
 667  * It is not necessarily just the upper level directory, empty or not
 668  * recognized sys directories are ignored.
 669  *
 670  * It can be called as many times as needed, without caring about
 671  * references.
 672  *
 673  * Returns: a new udev device, or #NULL, if it no parent exist.
 674  **/
 675 struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
 676 {
 677         if (udev_device == NULL)
 678                 return NULL;
 679         if (!udev_device->parent_set) {
 680                 udev_device->parent_set = true;
 681                 udev_device->parent_device = device_new_from_parent(udev_device);
 682         }
 683         if (udev_device->parent_device != NULL)
 684                 dbg(udev_device->udev, "returning existing parent %p\n", udev_device->parent_device);
 685         return udev_device->parent_device;
 686 }
 687
 688 /**
 689  * udev_device_get_parent_with_subsystem_devtype:
 690  * @udev_device: udev device to start searching from
 691  * @subsystem: the subsystem of the device
 692  * @devtype: the type (DEVTYPE) of the device
 693  *
 694  * Find the next parent device, with a matching subsystem and devtype
 695  * value, and fill in information from the sys device and the udev
 696  * database entry.
 697  *
 698  * If devtype is #NULL, only subsystem is checked, and any devtype will
 699  * match.
 700  *
 701  * The returned the device is not referenced. It is attached to the
 702  * child device, and will be cleaned up when the child device
 703  * is cleaned up.
 704  *
 705  * It can be called as many times as needed, without caring about
 706  * references.
 707  *
 708  * Returns: a new udev device, or #NULL if no matching parent exists.
 709  **/
 710 struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device, const char *subsystem, const char *devtype)
 711 {
 712         struct udev_device *parent;
 713
 714         if (subsystem == NULL)
 715                 return NULL;
 716
 717         parent = udev_device_get_parent(udev_device);
 718         while (parent != NULL) {
 719                 const char *parent_subsystem;
 720                 const char *parent_devtype;
 721
 722                 parent_subsystem = udev_device_get_subsystem(parent);
 723                 if (parent_subsystem != NULL && strcmp(parent_subsystem, subsystem) == 0) {
 724                         if (devtype == NULL)
 725                                 break;
 726                         parent_devtype = udev_device_get_devtype(parent);
 727                         if (parent_devtype != NULL && strcmp(parent_devtype, devtype) == 0)
 728                                 break;
 729                 }
 730                 parent = udev_device_get_parent(parent);
 731         }
 732         return parent;
 733 }
 734
 735 /**
 736  * udev_device_get_udev:
 737  * @udev_device: udev device
 738  *
 739  * Retrieve the udev library context the device was created with.
 740  *
 741  * Returns: the udev library context
 742  **/
 743 struct udev *udev_device_get_udev(struct udev_device *udev_device)
 744 {
 745         if (udev_device == NULL)
 746                 return NULL;
 747         return udev_device->udev;
 748 }
 749
 750 /**
 751  * udev_device_ref:
 752  * @udev_device: udev device
 753  *
 754  * Take a reference of a udev device.
 755  *
 756  * Returns: the passed udev device
 757  **/
 758 struct udev_device *udev_device_ref(struct udev_device *udev_device)
 759 {
 760         if (udev_device == NULL)
 761                 return NULL;
 762         udev_device->refcount++;
 763         return udev_device;
 764 }
 765
 766 /**
 767  * udev_device_unref:
 768  * @udev_device: udev device
 769  *
 770  * Drop a reference of a udev device. If the refcount reaches zero,
 771  * the resources of the device will be released.
 772  *
 773  **/
 774 void udev_device_unref(struct udev_device *udev_device)
 775 {
 776         if (udev_device == NULL)
 777                 return;
 778         udev_device->refcount--;
 779         if (udev_device->refcount > 0)
 780                 return;
 781         if (udev_device->parent_device != NULL)
 782                 udev_device_unref(udev_device->parent_device);
 783         free(udev_device->syspath);
 784         free(udev_device->sysname);
 785         free(udev_device->devnode);
 786         free(udev_device->subsystem);
 787         free(udev_device->devtype);
 788         udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
 789         udev_list_cleanup_entries(udev_device->udev, &udev_device->properties_list);
 790         udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
 791         udev_list_cleanup_entries(udev_device->udev, &udev_device->tags_list);
 792         free(udev_device->action);
 793         free(udev_device->driver);
 794         free(udev_device->devpath_old);
 795         free(udev_device->sysname_old);
 796         free(udev_device->knodename);
 797         free(udev_device->envp);
 798         free(udev_device->monitor_buf);
 799         dbg(udev_device->udev, "udev_device: %p released\n", udev_device);
 800         free(udev_device);
 801 }
 802
 803 /**
 804  * udev_device_get_devpath:
 805  * @udev_device: udev device
 806  *
 807  * Retrieve the kernel devpath value of the udev device. The path
 808  * does not contain the sys mount point, and starts with a '/'.
 809  *
 810  * Returns: the devpath of the udev device
 811  **/
 812 const char *udev_device_get_devpath(struct udev_device *udev_device)
 813 {
 814         if (udev_device == NULL)
 815                 return NULL;
 816         return udev_device->devpath;
 817 }
 818
 819 /**
 820  * udev_device_get_syspath:
 821  * @udev_device: udev device
 822  *
 823  * Retrieve the sys path of the udev device. The path is an
 824  * absolute path and starts with the sys mount point.
 825  *
 826  * Returns: the sys path of the udev device
 827  **/
 828 const char *udev_device_get_syspath(struct udev_device *udev_device)
 829 {
 830         if (udev_device == NULL)
 831                 return NULL;
 832         return udev_device->syspath;
 833 }
 834
 835 /**
 836  * udev_device_get_sysname:
 837  * @udev_device: udev device
 838  *
 839  * Returns: the sys name of the device device
 840  **/
 841 const char *udev_device_get_sysname(struct udev_device *udev_device)
 842 {
 843         if (udev_device == NULL)
 844                 return NULL;
 845         return udev_device->sysname;
 846 }
 847
 848 /**
 849  * udev_device_get_sysnum:
 850  * @udev_device: udev device
 851  *
 852  * Returns: the trailing number of of the device name
 853  **/
 854 const char *udev_device_get_sysnum(struct udev_device *udev_device)
 855 {
 856         if (udev_device == NULL)
 857                 return NULL;
 858         return udev_device->sysnum;
 859 }
 860
 861 /**
 862  * udev_device_get_devnode:
 863  * @udev_device: udev device
 864  *
 865  * Retrieve the device node file name belonging to the udev device.
 866  * The path is an absolute path, and starts with the device directory.
 867  *
 868  * Returns: the device node file name of the udev device, or #NULL if no device node exists
 869  **/
 870 const char *udev_device_get_devnode(struct udev_device *udev_device)
 871 {
 872         if (udev_device == NULL)
 873                 return NULL;
 874         if (!udev_device->info_loaded)
 875                 udev_device_read_db(udev_device);
 876         return udev_device->devnode;
 877 }
 878
 879 /**
 880  * udev_device_get_subsystem:
 881  * @udev_device: udev device
 882  *
 883  * Retrieve the subsystem string of the udev device. The string does not
 884  * contain any "/".
 885  *
 886  * Returns: the subsystem name of the udev device, or #NULL if it can not be determined
 887  **/
 888 const char *udev_device_get_subsystem(struct udev_device *udev_device)
 889 {
 890         char subsystem[UTIL_NAME_SIZE];
 891
 892         if (udev_device == NULL)
 893                 return NULL;
 894         if (!udev_device->subsystem_set) {
 895                 udev_device->subsystem_set = true;
 896                 /* read "subsystem" link */
 897                 if (util_get_sys_subsystem(udev_device->udev, udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
 898                         udev_device_set_subsystem(udev_device, subsystem);
 899                         return udev_device->subsystem;
 900                 }
 901                 /* implicit names */
 902                 if (strncmp(udev_device->devpath, "/module/", 8) == 0) {
 903                         udev_device_set_subsystem(udev_device, "module");
 904                         return udev_device->subsystem;
 905                 }
 906                 if (strstr(udev_device->devpath, "/drivers/") != NULL) {
 907                         udev_device_set_subsystem(udev_device, "drivers");
 908                         return udev_device->subsystem;
 909                 }
 910                 if (strncmp(udev_device->devpath, "/subsystem/", 11) == 0 ||
 911                     strncmp(udev_device->devpath, "/class/", 7) == 0 ||
 912                     strncmp(udev_device->devpath, "/bus/", 5) == 0) {
 913                         udev_device_set_subsystem(udev_device, "subsystem");
 914                         return udev_device->subsystem;
 915                 }
 916         }
 917         return udev_device->subsystem;
 918 }
 919
 920 /**
 921  * udev_device_get_devtype:
 922  * @udev_device: udev device
 923  *
 924  * Retrieve the devtype string of the udev device.
 925  *
 926  * Returns: the devtype name of the udev device, or #NULL if it can not be determined
 927  **/
 928 const char *udev_device_get_devtype(struct udev_device *udev_device)
 929 {
 930         if (udev_device == NULL)
 931                 return NULL;
 932         if (!udev_device->devtype_set) {
 933                 udev_device->devtype_set = true;
 934                 udev_device_read_uevent_file(udev_device);
 935         }
 936         return udev_device->devtype;
 937 }
 938
 939 /**
 940  * udev_device_get_devlinks_list_entry:
 941  * @udev_device: udev device
 942  *
 943  * Retrieve the list of device links pointing to the device file of
 944  * the udev device. The next list entry can be retrieved with
 945  * udev_list_entry_next(), which returns #NULL if no more entries exist.
 946  * The devlink path can be retrieved from the list entry by
 947  * udev_list_entry_get_name(). The path is an absolute path, and starts with
 948  * the device directory.
 949  *
 950  * Returns: the first entry of the device node link list
 951  **/
 952 struct udev_list_entry *udev_device_get_devlinks_list_entry(struct udev_device *udev_device)
 953 {
 954         if (udev_device == NULL)
 955                 return NULL;
 956         if (!udev_device->info_loaded)
 957                 udev_device_read_db(udev_device);
 958         return udev_list_get_entry(&udev_device->devlinks_list);
 959 }
 960
 961 void udev_device_cleanup_devlinks_list(struct udev_device *udev_device)
 962 {
 963         udev_device->devlinks_uptodate = false;
 964         udev_list_cleanup_entries(udev_device->udev, &udev_device->devlinks_list);
 965 }
 966
 967 /**
 968  * udev_device_get_properties_list_entry:
 969  * @udev_device: udev device
 970  *
 971  * Retrieve the list of key/value device properties of the udev
 972  * device. The next list entry can be retrieved with udev_list_entry_next(),
 973  * which returns #NULL if no more entries exist. The property name
 974  * can be retrieved from the list entry by udev_list_get_name(),
 975  * the property value by udev_list_get_value().
 976  *
 977  * Returns: the first entry of the property list
 978  **/
 979 struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device *udev_device)
 980 {
 981         if (udev_device == NULL)
 982                 return NULL;
 983         if (!udev_device->info_loaded) {
 984                 udev_device_read_uevent_file(udev_device);
 985                 udev_device_read_db(udev_device);
 986         }
 987         if (!udev_device->devlinks_uptodate) {
 988                 char symlinks[UTIL_PATH_SIZE];
 989                 struct udev_list_entry *list_entry;
 990
 991                 udev_device->devlinks_uptodate = true;
 992                 list_entry = udev_device_get_devlinks_list_entry(udev_device);
 993                 if (list_entry != NULL) {
 994                         char *s;
 995                         size_t l;
 996
 997                         s = symlinks;
 998                         l = util_strpcpyl(&s, sizeof(symlinks), udev_list_entry_get_name(list_entry), NULL);
 999                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
1000                                 l = util_strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry), NULL);
1001                         udev_device_add_property(udev_device, "DEVLINKS", symlinks);
1002                 }
1003         }
1004         if (!udev_device->tags_uptodate) {
1005                 udev_device->tags_uptodate = true;
1006                 if (udev_device_get_tags_list_entry(udev_device) != NULL) {
1007                         char tags[UTIL_PATH_SIZE];
1008                         struct udev_list_entry *list_entry;
1009                         char *s;
1010                         size_t l;
1011
1012                         s = tags;
1013                         l = util_strpcpyl(&s, sizeof(tags), ":", NULL);
1014                         udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
1015                                 l = util_strpcpyl(&s, l, udev_list_entry_get_name(list_entry), ":", NULL);
1016                         udev_device_add_property(udev_device, "TAGS", tags);
1017                 }
1018         }
1019         return udev_list_get_entry(&udev_device->properties_list);
1020 }
1021
1022 /**
1023  * udev_device_get_driver:
1024  * @udev_device: udev device
1025  *
1026  * Returns: the driver string, or #NULL if there is no driver attached.
1027  **/
1028 const char *udev_device_get_driver(struct udev_device *udev_device)
1029 {
1030         char driver[UTIL_NAME_SIZE];
1031
1032         if (udev_device == NULL)
1033                 return NULL;
1034         if (!udev_device->driver_set) {
1035                 udev_device->driver_set = true;
1036                 if (util_get_sys_driver(udev_device->udev, udev_device->syspath, driver, sizeof(driver)) > 0)
1037                         udev_device->driver = strdup(driver);
1038         }
1039         return udev_device->driver;
1040 }
1041
1042 /**
1043  * udev_device_get_devnum:
1044  * @udev_device: udev device
1045  *
1046  * Returns: the device major/minor number.
1047  **/
1048 dev_t udev_device_get_devnum(struct udev_device *udev_device)
1049 {
1050         if (udev_device == NULL)
1051                 return makedev(0, 0);
1052         if (!udev_device->info_loaded)
1053                 udev_device_read_uevent_file(udev_device);
1054         return udev_device->devnum;
1055 }
1056
1057 /**
1058  * udev_device_get_action:
1059  * @udev_device: udev device
1060  *
1061  * This is only valid if the device was received through a monitor. Devices read from
1062  * sys do not have an action string. Usual actions are: add, remove, change, online,
1063  * offline.
1064  *
1065  * Returns: the kernel action value, or #NULL if there is no action value available.
1066  **/
1067 const char *udev_device_get_action(struct udev_device *udev_device)
1068 {
1069         if (udev_device == NULL)
1070                 return NULL;
1071         return udev_device->action;
1072 }
1073
1074 /**
1075  * udev_device_get_devnum:
1076  * @udev_device: udev device
1077  *
1078  * This is only valid if the device was received through a monitor. Devices read from
1079  * sys do not have a sequence number.
1080  *
1081  * Returns: the kernel event sequence number, or 0 if there is no sequence number available.
1082  **/
1083 unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
1084 {
1085         if (udev_device == NULL)
1086                 return 0;
1087         return udev_device->seqnum;
1088 }
1089
1090 /**
1091  * udev_device_get_sysattr_value:
1092  * @udev_device: udev device
1093  * @sysattr: attribute name
1094  *
1095  * The retrieved value is cached in the device. Repeated calls will return the same
1096  * value and not open the attribute again.
1097  *
1098  * Returns: the content of a sys attribute file, or #NULL if there is no sys attribute value.
1099  **/
1100 const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
1101 {
1102         struct udev_list_entry *list_entry;
1103         char path[UTIL_PATH_SIZE];
1104         char value[4096];
1105         struct stat statbuf;
1106         int fd;
1107         ssize_t size;
1108         const char *val = NULL;
1109
1110         if (udev_device == NULL)
1111                 return NULL;
1112         if (sysattr == NULL)
1113                 return NULL;
1114
1115         /* look for possibly already cached result */
1116         udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_device->sysattr_list)) {
1117                 if (strcmp(udev_list_entry_get_name(list_entry), sysattr) == 0) {
1118                         dbg(udev_device->udev, "got '%s' (%s) from cache\n",
1119                             sysattr, udev_list_entry_get_value(list_entry));
1120                         return udev_list_entry_get_value(list_entry);
1121                 }
1122         }
1123
1124         util_strscpyl(path, sizeof(path), udev_device_get_syspath(udev_device), "/", sysattr, NULL);
1125         if (lstat(path, &statbuf) != 0) {
1126                 dbg(udev_device->udev, "no attribute '%s', keep negative entry\n", path);
1127                 udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, NULL, 0, 0);
1128                 goto out;
1129         }
1130
1131         if (S_ISLNK(statbuf.st_mode)) {
1132                 char target[UTIL_NAME_SIZE];
1133                 int len;
1134                 char *pos;
1135
1136                 /* some core links return the last element of the target path */
1137                 if (strcmp(sysattr, "driver") != 0 &&
1138                     strcmp(sysattr, "subsystem") != 0 &&
1139                     strcmp(sysattr, "module") != 0)
1140                         goto out;
1141
1142                 len = readlink(path, target, sizeof(target));
1143                 if (len <= 0 || len == sizeof(target))
1144                         goto out;
1145                 target[len] = '\0';
1146
1147                 pos = strrchr(target, '/');
1148                 if (pos != NULL) {
1149                         pos = &pos[1];
1150                         dbg(udev_device->udev, "cache '%s' with link value '%s'\n", sysattr, pos);
1151                         list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, pos, 0, 0);
1152                         val = udev_list_entry_get_value(list_entry);
1153                 }
1154
1155                 goto out;
1156         }
1157
1158         /* skip directories */
1159         if (S_ISDIR(statbuf.st_mode))
1160                 goto out;
1161
1162         /* skip non-readable files */
1163         if ((statbuf.st_mode & S_IRUSR) == 0)
1164                 goto out;
1165
1166         /* read attribute value */
1167         fd = open(path, O_RDONLY|O_CLOEXEC);
1168         if (fd < 0) {
1169                 dbg(udev_device->udev, "attribute '%s' can not be opened\n", path);
1170                 goto out;
1171         }
1172         size = read(fd, value, sizeof(value));
1173         close(fd);
1174         if (size < 0)
1175                 goto out;
1176         if (size == sizeof(value))
1177                 goto out;
1178
1179         /* got a valid value, store it in cache and return it */
1180         value[size] = '\0';
1181         util_remove_trailing_chars(value, '\n');
1182         dbg(udev_device->udev, "'%s' has attribute value '%s'\n", path, value);
1183         list_entry = udev_list_entry_add(udev_device->udev, &udev_device->sysattr_list, sysattr, value, 0, 0);
1184         val = udev_list_entry_get_value(list_entry);
1185 out:
1186         return val;
1187 }
1188
1189 int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath)
1190 {
1191         const char *pos;
1192         size_t len;
1193
1194         free(udev_device->syspath);
1195         udev_device->syspath = strdup(syspath);
1196         if (udev_device->syspath ==  NULL)
1197                 return -ENOMEM;
1198         udev_device->devpath = &udev_device->syspath[strlen(udev_get_sys_path(udev_device->udev))];
1199         udev_device_add_property(udev_device, "DEVPATH", udev_device->devpath);
1200
1201         pos = strrchr(udev_device->syspath, '/');
1202         if (pos == NULL)
1203                 return -EINVAL;
1204         udev_device->sysname = strdup(&pos[1]);
1205         if (udev_device->sysname == NULL)
1206                 return -ENOMEM;
1207
1208         /* some devices have '!' in their name, change that to '/' */
1209         len = 0;
1210         while (udev_device->sysname[len] != '\0') {
1211                 if (udev_device->sysname[len] == '!')
1212                         udev_device->sysname[len] = '/';
1213                 len++;
1214         }
1215
1216         /* trailing number */
1217         while (len > 0 && isdigit(udev_device->sysname[--len]))
1218                 udev_device->sysnum = &udev_device->sysname[len];
1219
1220         /* sysname is completely numeric */
1221         if (len == 0)
1222                 udev_device->sysnum = NULL;
1223
1224         return 0;
1225 }
1226
1227 int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem)
1228 {
1229         free(udev_device->subsystem);
1230         udev_device->subsystem = strdup(subsystem);
1231         if (udev_device->subsystem == NULL)
1232                 return -ENOMEM;
1233         udev_device->subsystem_set = true;
1234         udev_device_add_property(udev_device, "SUBSYSTEM", udev_device->subsystem);
1235         return 0;
1236 }
1237
1238 int udev_device_set_devtype(struct udev_device *udev_device, const char *devtype)
1239 {
1240         free(udev_device->devtype);
1241         udev_device->devtype = strdup(devtype);
1242         if (udev_device->devtype == NULL)
1243                 return -ENOMEM;
1244         udev_device->devtype_set = true;
1245         udev_device_add_property(udev_device, "DEVTYPE", udev_device->devtype);
1246         return 0;
1247 }
1248
1249 int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode)
1250 {
1251         free(udev_device->devnode);
1252         udev_device->devnode = strdup(devnode);
1253         if (devnode == NULL)
1254                 return 0;
1255         if (udev_device->devnode == NULL)
1256                 return -ENOMEM;
1257         udev_device_add_property(udev_device, "DEVNAME", udev_device->devnode);
1258         return 0;
1259 }
1260
1261 int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink, int unique)
1262 {
1263         struct udev_list_entry *list_entry;
1264
1265         udev_device->devlinks_uptodate = false;
1266         list_entry = udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, 1, 0);
1267         if (list_entry == NULL)
1268                 return -ENOMEM;
1269         if (unique)
1270                 udev_list_entry_set_flags(list_entry, 1);
1271         return 0;
1272 }
1273
1274 int udev_device_add_tag(struct udev_device *udev_device, const char *tag)
1275 {
1276         if (strchr(tag, ':') != NULL || strchr(tag, ' ') != NULL)
1277                 return -EINVAL;
1278         udev_device->tags_uptodate = false;
1279         if (udev_list_entry_add(udev_device->udev, &udev_device->tags_list, tag, NULL, 1, 0) != NULL)
1280                 return 0;
1281         return -ENOMEM;
1282 }
1283
1284 void udev_device_cleanup_tags_list(struct udev_device *udev_device)
1285 {
1286         udev_device->tags_uptodate = false;
1287         udev_list_cleanup_entries(udev_device->udev, &udev_device->tags_list);
1288 }
1289
1290 /**
1291  * udev_device_get_tags_list_entry:
1292  * @udev_device: udev device
1293  *
1294  * Retrieve the list of tags attached to the udev device. The next
1295  * list entry can be retrieved with udev_list_entry_next(),
1296  * which returns #NULL if no more entries exist. The tag string
1297  * can be retrieved from the list entry by udev_list_get_name().
1298  *
1299  * Returns: the first entry of the tag list
1300  **/
1301 struct udev_list_entry *udev_device_get_tags_list_entry(struct udev_device *udev_device)
1302 {
1303         if (udev_device == NULL)
1304                 return NULL;
1305         return udev_list_get_entry(&udev_device->tags_list);
1306 }
1307
1308 int udev_device_has_tag(struct udev_device *udev_device, const char *tag)
1309 {
1310         struct udev_list_entry *list_entry;
1311
1312         if (!udev_device->info_loaded)
1313                 udev_device_read_db(udev_device);
1314         list_entry = udev_device_get_tags_list_entry(udev_device);
1315         list_entry =  udev_list_entry_get_by_name(list_entry, tag);
1316         if (list_entry != NULL)
1317                 return 1;
1318         return 0;
1319 }
1320
1321 #define ENVP_SIZE                       128
1322 #define MONITOR_BUF_SIZE                4096
1323 static int update_envp_monitor_buf(struct udev_device *udev_device)
1324 {
1325         struct udev_list_entry *list_entry;
1326         char *s;
1327         size_t l;
1328         unsigned int i;
1329
1330         /* monitor buffer of property strings */
1331         free(udev_device->monitor_buf);
1332         udev_device->monitor_buf_len = 0;
1333         udev_device->monitor_buf = malloc(MONITOR_BUF_SIZE);
1334         if (udev_device->monitor_buf == NULL)
1335                 return -ENOMEM;
1336
1337         /* envp array, strings will point into monitor buffer */
1338         if (udev_device->envp == NULL)
1339                 udev_device->envp = malloc(sizeof(char *) * ENVP_SIZE);
1340         if (udev_device->envp == NULL)
1341                 return -ENOMEM;
1342
1343         i = 0;
1344         s = udev_device->monitor_buf;
1345         l = MONITOR_BUF_SIZE;
1346         udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
1347                 const char *key;
1348
1349                 key = udev_list_entry_get_name(list_entry);
1350                 /* skip private variables */
1351                 if (key[0] == '.')
1352                         continue;
1353
1354                 /* add string to envp array */
1355                 udev_device->envp[i++] = s;
1356                 if (i+1 >= ENVP_SIZE)
1357                         return -EINVAL;
1358
1359                 /* add property string to monitor buffer */
1360                 l = util_strpcpyl(&s, l, key, "=", udev_list_entry_get_value(list_entry), NULL);
1361                 if (l == 0)
1362                         return -EINVAL;
1363                 /* advance past the trailing '\0' that util_strpcpyl() guarantees */
1364                 s++;
1365                 l--;
1366         }
1367         udev_device->envp[i] = NULL;
1368         udev_device->monitor_buf_len = s - udev_device->monitor_buf;
1369         udev_device->envp_uptodate = true;
1370         dbg(udev_device->udev, "filled envp/monitor buffer, %u properties, %zu bytes\n",
1371             i, udev_device->monitor_buf_len);
1372         return 0;
1373 }
1374
1375 char **udev_device_get_properties_envp(struct udev_device *udev_device)
1376 {
1377         if (!udev_device->envp_uptodate)
1378                 if (update_envp_monitor_buf(udev_device) != 0)
1379                         return NULL;
1380         return udev_device->envp;
1381 }
1382
1383 ssize_t udev_device_get_properties_monitor_buf(struct udev_device *udev_device, const char **buf)
1384 {
1385         if (!udev_device->envp_uptodate)
1386                 if (update_envp_monitor_buf(udev_device) != 0)
1387                         return -EINVAL;
1388         *buf = udev_device->monitor_buf;
1389         return udev_device->monitor_buf_len;
1390 }
1391
1392 int udev_device_set_action(struct udev_device *udev_device, const char *action)
1393 {
1394         free(udev_device->action);
1395         udev_device->action = strdup(action);
1396         if (udev_device->action == NULL)
1397                 return -ENOMEM;
1398         udev_device_add_property(udev_device, "ACTION", udev_device->action);
1399         return 0;
1400 }
1401
1402 int udev_device_set_driver(struct udev_device *udev_device, const char *driver)
1403 {
1404         free(udev_device->driver);
1405         udev_device->driver = strdup(driver);
1406         if (udev_device->driver == NULL)
1407                 return -ENOMEM;
1408         udev_device->driver_set = true;
1409         udev_device_add_property(udev_device, "DRIVER", udev_device->driver);
1410         return 0;
1411 }
1412
1413 const char *udev_device_get_devpath_old(struct udev_device *udev_device)
1414 {
1415         return udev_device->devpath_old;
1416 }
1417
1418 int udev_device_set_devpath_old(struct udev_device *udev_device, const char *devpath_old)
1419 {
1420         const char *pos;
1421         size_t len;
1422
1423         free(udev_device->devpath_old);
1424         udev_device->devpath_old = strdup(devpath_old);
1425         if (udev_device->devpath_old == NULL)
1426                 return -ENOMEM;
1427         udev_device_add_property(udev_device, "DEVPATH_OLD", udev_device->devpath_old);
1428
1429         pos = strrchr(udev_device->devpath_old, '/');
1430         if (pos == NULL)
1431                 return -EINVAL;
1432         udev_device->sysname_old = strdup(&pos[1]);
1433         if (udev_device->sysname_old == NULL)
1434                 return -ENOMEM;
1435
1436         /* some devices have '!' in their name, change that to '/' */
1437         len = 0;
1438         while (udev_device->sysname_old[len] != '\0') {
1439                 if (udev_device->sysname_old[len] == '!')
1440                         udev_device->sysname_old[len] = '/';
1441                 len++;
1442         }
1443         return 0;
1444 }
1445
1446 const char *udev_device_get_sysname_old(struct udev_device *udev_device)
1447 {
1448         if (udev_device == NULL)
1449                 return NULL;
1450         return udev_device->sysname_old;
1451 }
1452
1453 const char *udev_device_get_knodename(struct udev_device *udev_device)
1454 {
1455         return udev_device->knodename;
1456 }
1457
1458 int udev_device_set_knodename(struct udev_device *udev_device, const char *knodename)
1459 {
1460         free(udev_device->knodename);
1461         udev_device->knodename = strdup(knodename);
1462         if (udev_device->knodename == NULL)
1463                 return -ENOMEM;
1464         udev_device_add_property(udev_device, "DEVNAME", udev_device->knodename);
1465         return 0;
1466 }
1467
1468 int udev_device_get_timeout(struct udev_device *udev_device)
1469 {
1470         return udev_device->timeout;
1471 }
1472
1473 int udev_device_set_timeout(struct udev_device *udev_device, int timeout)
1474 {
1475         udev_device->timeout = timeout;
1476         return 0;
1477 }
1478 int udev_device_get_event_timeout(struct udev_device *udev_device)
1479 {
1480         if (!udev_device->info_loaded)
1481                 udev_device_read_db(udev_device);
1482         return udev_device->event_timeout;
1483 }
1484
1485 int udev_device_set_event_timeout(struct udev_device *udev_device, int event_timeout)
1486 {
1487         udev_device->event_timeout = event_timeout;
1488         return 0;
1489 }
1490
1491 int udev_device_set_seqnum(struct udev_device *udev_device, unsigned long long int seqnum)
1492 {
1493         char num[32];
1494
1495         udev_device->seqnum = seqnum;
1496         snprintf(num, sizeof(num), "%llu", seqnum);
1497         udev_device_add_property(udev_device, "SEQNUM", num);
1498         return 0;
1499 }
1500
1501 int udev_device_set_devnum(struct udev_device *udev_device, dev_t devnum)
1502 {
1503         char num[32];
1504
1505         udev_device->devnum = devnum;
1506
1507         snprintf(num, sizeof(num), "%u", major(devnum));
1508         udev_device_add_property(udev_device, "MAJOR", num);
1509         snprintf(num, sizeof(num), "%u", minor(devnum));
1510         udev_device_add_property(udev_device, "MINOR", num);
1511         return 0;
1512 }
1513
1514 int udev_device_get_devlink_priority(struct udev_device *udev_device)
1515 {
1516         if (!udev_device->info_loaded)
1517                 udev_device_read_db(udev_device);
1518         return udev_device->devlink_priority;
1519 }
1520
1521 int udev_device_set_devlink_priority(struct udev_device *udev_device, int prio)
1522 {
1523          udev_device->devlink_priority = prio;
1524         return 0;
1525 }
1526
1527 int udev_device_get_watch_handle(struct udev_device *udev_device)
1528 {
1529         if (!udev_device->info_loaded)
1530                 udev_device_read_db(udev_device);
1531         return udev_device->watch_handle;
1532 }
1533
1534 int udev_device_set_watch_handle(struct udev_device *udev_device, int handle)
1535 {
1536         udev_device->watch_handle = handle;
1537         return 0;
1538 }