src/udev/udevadm-hwdb.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2012 Kay Sievers <kay@vrfy.org>
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <getopt.h>
  23 #include <string.h>
  24 #include <ctype.h>
  25
  26 #include "util.h"
  27 #include "strbuf.h"
  28 #include "conf-files.h"
  29
  30 #include "udev.h"
  31 #include "libudev-hwdb-def.h"
  32
  33 /*
  34  * Generic udev properties, key/value database based on modalias strings.
  35  * Uses a Patricia/radix trie to index all matches for efficient lookup.
  36  */
  37
  38 static const char * const conf_file_dirs[] = {
  39         "/etc/udev/hwdb.d",
  40         UDEVLIBEXECDIR "/hwdb.d",
  41         NULL
  42 };
  43
  44 /* in-memory trie objects */
  45 struct trie {
  46         struct trie_node *root;
  47         struct strbuf *strings;
  48
  49         size_t nodes_count;
  50         size_t children_count;
  51         size_t values_count;
  52 };
  53
  54 struct trie_node {
  55         /* prefix, common part for all children of this node */
  56         size_t prefix_off;
  57
  58         /* sorted array of pointers to children nodes */
  59         struct trie_child_entry *children;
  60         uint8_t children_count;
  61
  62         /* sorted array of key/value pairs */
  63         struct trie_value_entry *values;
  64         size_t values_count;
  65 };
  66
  67 /* children array item with char (0-255) index */
  68 struct trie_child_entry {
  69         uint8_t c;
  70         struct trie_node *child;
  71 };
  72
  73 /* value array item with key/value pairs */
  74 struct trie_value_entry {
  75         size_t key_off;
  76         size_t value_off;
  77 };
  78
  79 static int trie_children_cmp(const void *v1, const void *v2) {
  80         const struct trie_child_entry *n1 = v1;
  81         const struct trie_child_entry *n2 = v2;
  82
  83         return n1->c - n2->c;
  84 }
  85
  86 static int node_add_child(struct trie *trie, struct trie_node *node, struct trie_node *node_child, uint8_t c) {
  87         struct trie_child_entry *child;
  88
  89         /* extend array, add new entry, sort for bisection */
  90         child = realloc(node->children, (node->children_count + 1) * sizeof(struct trie_child_entry));
  91         if (!child)
  92                 return -ENOMEM;
  93
  94         node->children = child;
  95         trie->children_count++;
  96         node->children[node->children_count].c = c;
  97         node->children[node->children_count].child = node_child;
  98         node->children_count++;
  99         qsort(node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
 100         trie->nodes_count++;
 101
 102         return 0;
 103 }
 104
 105 static struct trie_node *node_lookup(const struct trie_node *node, uint8_t c) {
 106         struct trie_child_entry *child;
 107         struct trie_child_entry search;
 108
 109         search.c = c;
 110         child = bsearch(&search, node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
 111         if (child)
 112                 return child->child;
 113         return NULL;
 114 }
 115
 116 static void trie_node_cleanup(struct trie_node *node) {
 117         size_t i;
 118
 119         for (i = 0; i < node->children_count; i++)
 120                 trie_node_cleanup(node->children[i].child);
 121         free(node->children);
 122         free(node->values);
 123         free(node);
 124 }
 125
 126 static int trie_values_cmp(const void *v1, const void *v2, void *arg) {
 127         const struct trie_value_entry *val1 = v1;
 128         const struct trie_value_entry *val2 = v2;
 129         struct trie *trie = arg;
 130
 131         return strcmp(trie->strings->buf + val1->key_off,
 132                       trie->strings->buf + val2->key_off);
 133 }
 134
 135 static int trie_node_add_value(struct trie *trie, struct trie_node *node,
 136                           const char *key, const char *value) {
 137         ssize_t k, v;
 138         struct trie_value_entry *val;
 139
 140         k = strbuf_add_string(trie->strings, key, strlen(key));
 141         if (k < 0)
 142                 return k;
 143         v = strbuf_add_string(trie->strings, value, strlen(value));
 144         if (v < 0)
 145                 return v;
 146
 147         if (node->values_count) {
 148                 struct trie_value_entry search = {
 149                         .key_off = k,
 150                         .value_off = v,
 151                 };
 152
 153                 val = xbsearch_r(&search, node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
 154                 if (val) {
 155                         /* replace existing earlier key with new value */
 156                         val->value_off = v;
 157                         return 0;
 158                 }
 159         }
 160
 161         /* extend array, add new entry, sort for bisection */
 162         val = realloc(node->values, (node->values_count + 1) * sizeof(struct trie_value_entry));
 163         if (!val)
 164                 return -ENOMEM;
 165         trie->values_count++;
 166         node->values = val;
 167         node->values[node->values_count].key_off = k;
 168         node->values[node->values_count].value_off = v;
 169         node->values_count++;
 170         qsort_r(node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
 171         return 0;
 172 }
 173
 174 static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,
 175                        const char *key, const char *value) {
 176         size_t i = 0;
 177         int err = 0;
 178
 179         for (;;) {
 180                 size_t p;
 181                 uint8_t c;
 182                 struct trie_node *child;
 183
 184                 for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {
 185                         _cleanup_free_ char *s = NULL;
 186                         ssize_t off;
 187                         _cleanup_free_ struct trie_node *new_child = NULL;
 188
 189                         if (c == search[i + p])
 190                                 continue;
 191
 192                         /* split node */
 193                         new_child = calloc(sizeof(struct trie_node), 1);
 194                         if (!new_child)
 195                                 return -ENOMEM;
 196
 197                         /* move values from parent to child */
 198                         new_child->prefix_off = node->prefix_off + p+1;
 199                         new_child->children = node->children;
 200                         new_child->children_count = node->children_count;
 201                         new_child->values = node->values;
 202                         new_child->values_count = node->values_count;
 203
 204                         /* update parent; use strdup() because the source gets realloc()d */
 205                         s = strndup(trie->strings->buf + node->prefix_off, p);
 206                         if (!s)
 207                                 return -ENOMEM;
 208
 209                         off = strbuf_add_string(trie->strings, s, p);
 210                         if (off < 0)
 211                                 return off;
 212
 213                         node->prefix_off = off;
 214                         node->children = NULL;
 215                         node->children_count = 0;
 216                         node->values = NULL;
 217                         node->values_count = 0;
 218                         err = node_add_child(trie, node, new_child, c);
 219                         if (err)
 220                                 return err;
 221
 222                         new_child = NULL; /* avoid cleanup */
 223                         break;
 224                 }
 225                 i += p;
 226
 227                 c = search[i];
 228                 if (c == '\0')
 229                         return trie_node_add_value(trie, node, key, value);
 230
 231                 child = node_lookup(node, c);
 232                 if (!child) {
 233                         ssize_t off;
 234
 235                         /* new child */
 236                         child = calloc(sizeof(struct trie_node), 1);
 237                         if (!child)
 238                                 return -ENOMEM;
 239
 240                         off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));
 241                         if (off < 0) {
 242                                 free(child);
 243                                 return off;
 244                         }
 245
 246                         child->prefix_off = off;
 247                         err = node_add_child(trie, node, child, c);
 248                         if (err) {
 249                                 free(child);
 250                                 return err;
 251                         }
 252
 253                         return trie_node_add_value(trie, child, key, value);
 254                 }
 255
 256                 node = child;
 257                 i++;
 258         }
 259 }
 260
 261 struct trie_f {
 262         FILE *f;
 263         struct trie *trie;
 264         uint64_t strings_off;
 265
 266         uint64_t nodes_count;
 267         uint64_t children_count;
 268         uint64_t values_count;
 269 };
 270
 271 /* calculate the storage space for the nodes, children arrays, value arrays */
 272 static void trie_store_nodes_size(struct trie_f *trie, struct trie_node *node) {
 273         uint64_t i;
 274
 275         for (i = 0; i < node->children_count; i++)
 276                 trie_store_nodes_size(trie, node->children[i].child);
 277
 278         trie->strings_off += sizeof(struct trie_node_f);
 279         for (i = 0; i < node->children_count; i++)
 280                 trie->strings_off += sizeof(struct trie_child_entry_f);
 281         for (i = 0; i < node->values_count; i++)
 282                 trie->strings_off += sizeof(struct trie_value_entry_f);
 283 }
 284
 285 static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node) {
 286         uint64_t i;
 287         struct trie_node_f n = {
 288                 .prefix_off = htole64(trie->strings_off + node->prefix_off),
 289                 .children_count = node->children_count,
 290                 .values_count = htole64(node->values_count),
 291         };
 292         struct trie_child_entry_f *children = NULL;
 293         int64_t node_off;
 294
 295         if (node->children_count) {
 296                 children = new0(struct trie_child_entry_f, node->children_count);
 297                 if (!children)
 298                         return -ENOMEM;
 299         }
 300
 301         /* post-order recursion */
 302         for (i = 0; i < node->children_count; i++) {
 303                 int64_t child_off;
 304
 305                 child_off = trie_store_nodes(trie, node->children[i].child);
 306                 if (child_off < 0) {
 307                         free(children);
 308                         return child_off;
 309                 }
 310                 children[i].c = node->children[i].c;
 311                 children[i].child_off = htole64(child_off);
 312         }
 313
 314         /* write node */
 315         node_off = ftello(trie->f);
 316         fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);
 317         trie->nodes_count++;
 318
 319         /* append children array */
 320         if (node->children_count) {
 321                 fwrite(children, sizeof(struct trie_child_entry_f), node->children_count, trie->f);
 322                 trie->children_count += node->children_count;
 323                 free(children);
 324         }
 325
 326         /* append values array */
 327         for (i = 0; i < node->values_count; i++) {
 328                 struct trie_value_entry_f v = {
 329                         .key_off = htole64(trie->strings_off + node->values[i].key_off),
 330                         .value_off = htole64(trie->strings_off + node->values[i].value_off),
 331                 };
 332
 333                 fwrite(&v, sizeof(struct trie_value_entry_f), 1, trie->f);
 334                 trie->values_count++;
 335         }
 336
 337         return node_off;
 338 }
 339
 340 static int trie_store(struct trie *trie, const char *filename) {
 341         struct trie_f t = {
 342                 .trie = trie,
 343         };
 344         char *filename_tmp;
 345         int64_t pos;
 346         int64_t root_off;
 347         int64_t size;
 348         struct trie_header_f h = {
 349                 .signature = HWDB_SIG,
 350                 .tool_version = htole64(atoi(VERSION)),
 351                 .header_size = htole64(sizeof(struct trie_header_f)),
 352                 .node_size = htole64(sizeof(struct trie_node_f)),
 353                 .child_entry_size = htole64(sizeof(struct trie_child_entry_f)),
 354                 .value_entry_size = htole64(sizeof(struct trie_value_entry_f)),
 355         };
 356         int err;
 357
 358         /* calculate size of header, nodes, children entries, value entries */
 359         t.strings_off = sizeof(struct trie_header_f);
 360         trie_store_nodes_size(&t, trie->root);
 361
 362         err = fopen_temporary(filename , &t.f, &filename_tmp);
 363         if (err < 0)
 364                 return err;
 365         fchmod(fileno(t.f), 0444);
 366
 367         /* write nodes */
 368         fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET);
 369         root_off = trie_store_nodes(&t, trie->root);
 370         h.nodes_root_off = htole64(root_off);
 371         pos = ftello(t.f);
 372         h.nodes_len = htole64(pos - sizeof(struct trie_header_f));
 373
 374         /* write string buffer */
 375         fwrite(trie->strings->buf, trie->strings->len, 1, t.f);
 376         h.strings_len = htole64(trie->strings->len);
 377
 378         /* write header */
 379         size = ftello(t.f);
 380         h.file_size = htole64(size);
 381         fseeko(t.f, 0, SEEK_SET);
 382         fwrite(&h, sizeof(struct trie_header_f), 1, t.f);
 383         err = ferror(t.f);
 384         if (err)
 385                 err = -errno;
 386         fclose(t.f);
 387         if (err < 0 || rename(filename_tmp, filename) < 0) {
 388                 unlink(filename_tmp);
 389                 goto out;
 390         }
 391
 392         log_debug("=== trie on-disk ===\n");
 393         log_debug("size:             %8llu bytes\n", (unsigned long long)size);
 394         log_debug("header:           %8zu bytes\n", sizeof(struct trie_header_f));
 395         log_debug("nodes:            %8llu bytes (%8llu)\n",
 396                   (unsigned long long)t.nodes_count * sizeof(struct trie_node_f), (unsigned long long)t.nodes_count);
 397         log_debug("child pointers:   %8llu bytes (%8llu)\n",
 398                   (unsigned long long)t.children_count * sizeof(struct trie_child_entry_f), (unsigned long long)t.children_count);
 399         log_debug("value pointers:   %8llu bytes (%8llu)\n",
 400                   (unsigned long long)t.values_count * sizeof(struct trie_value_entry_f), (unsigned long long)t.values_count);
 401         log_debug("string store:     %8llu bytes\n", (unsigned long long)trie->strings->len);
 402         log_debug("strings start:    %8llu\n", (unsigned long long) t.strings_off);
 403 out:
 404         free(filename_tmp);
 405         return err;
 406 }
 407
 408 static int insert_data(struct trie *trie, struct udev_list *match_list,
 409                        char *line, const char *filename) {
 410         char *value;
 411         struct udev_list_entry *entry;
 412
 413         value = strchr(line, '=');
 414         if (!value) {
 415                 log_error("Error, key/value pair expected but got '%s' in '%s':\n", line, filename);
 416                 return -EINVAL;
 417         }
 418
 419         value[0] = '\0';
 420         value++;
 421
 422         if (line[0] == '\0' || value[0] == '\0') {
 423                 log_error("Error, empty key or value '%s' in '%s':\n", line, filename);
 424                 return -EINVAL;
 425         }
 426
 427         udev_list_entry_foreach(entry, udev_list_get_entry(match_list))
 428                 trie_insert(trie, trie->root, udev_list_entry_get_name(entry), line, value);
 429
 430         return 0;
 431 }
 432
 433 static int import_file(struct udev *udev, struct trie *trie, const char *filename) {
 434         enum {
 435                 HW_MATCH,
 436                 HW_DATA,
 437                 HW_NONE,
 438         } state = HW_NONE;
 439         FILE *f;
 440         char line[LINE_MAX];
 441         struct udev_list match_list;
 442
 443         udev_list_init(udev, &match_list, false);
 444
 445         f = fopen(filename, "re");
 446         if (f == NULL)
 447                 return -errno;
 448
 449         while (fgets(line, sizeof(line), f)) {
 450                 size_t len;
 451                 char *pos;
 452
 453                 /* comment line */
 454                 if (line[0] == '#')
 455                         continue;
 456
 457                 /* strip trailing comment */
 458                 pos = strchr(line, '#');
 459                 if (pos)
 460                         pos[0] = '\0';
 461
 462                 /* strip trailing whitespace */
 463                 len = strlen(line);
 464                 while (len > 0 && isspace(line[len-1]))
 465                         len--;
 466                 line[len] = '\0';
 467
 468                 switch (state) {
 469                 case HW_NONE:
 470                         if (len == 0)
 471                                 break;
 472
 473                         if (line[0] == ' ') {
 474                                 log_error("Error, MATCH expected but got '%s' in '%s':\n", line, filename);
 475                                 break;
 476                         }
 477
 478                         /* start of record, first match */
 479                         state = HW_MATCH;
 480                         udev_list_entry_add(&match_list, line, NULL);
 481                         break;
 482
 483                 case HW_MATCH:
 484                         if (len == 0) {
 485                                 log_error("Error, DATA expected but got empty line in '%s':\n", filename);
 486                                 state = HW_NONE;
 487                                 udev_list_cleanup(&match_list);
 488                                 break;
 489                         }
 490
 491                         /* another match */
 492                         if (line[0] != ' ') {
 493                                 udev_list_entry_add(&match_list, line, NULL);
 494                                 break;
 495                         }
 496
 497                         /* first data */
 498                         state = HW_DATA;
 499                         insert_data(trie, &match_list, line, filename);
 500                         break;
 501
 502                 case HW_DATA:
 503                         /* end of record */
 504                         if (len == 0) {
 505                                 state = HW_NONE;
 506                                 udev_list_cleanup(&match_list);
 507                                 break;
 508                         }
 509
 510                         if (line[0] != ' ') {
 511                                 log_error("Error, DATA expected but got '%s' in '%s':\n", line, filename);
 512                                 state = HW_NONE;
 513                                 udev_list_cleanup(&match_list);
 514                                 break;
 515                         }
 516
 517                         insert_data(trie, &match_list, line, filename);
 518                         break;
 519                 };
 520         }
 521
 522         fclose(f);
 523         udev_list_cleanup(&match_list);
 524         return 0;
 525 }
 526
 527 static void help(void) {
 528         printf("Usage: udevadm hwdb OPTIONS\n"
 529                "  -u,--update          update the hardware database\n"
 530                "  -t,--test=MODALIAS   query database and print result\n"
 531                "  -r,--root=PATH       alternative root path in the filesystem\n"
 532                "  -h,--help\n\n");
 533 }
 534
 535 static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {
 536         static const struct option options[] = {
 537                 { "update", no_argument,       NULL, 'u' },
 538                 { "test",   required_argument, NULL, 't' },
 539                 { "root",   required_argument, NULL, 'r' },
 540                 { "help",   no_argument,       NULL, 'h' },
 541                 {}
 542         };
 543         const char *test = NULL;
 544         const char *root = "";
 545         bool update = false;
 546         struct trie *trie = NULL;
 547         int err, c;
 548         int rc = EXIT_SUCCESS;
 549
 550         while ((c = getopt_long(argc, argv, "ut:r:h", options, NULL)) >= 0)
 551                 switch(c) {
 552                 case 'u':
 553                         update = true;
 554                         break;
 555                 case 't':
 556                         test = optarg;
 557                         break;
 558                 case 'r':
 559                         root = optarg;
 560                         break;
 561                 case 'h':
 562                         help();
 563                         return EXIT_SUCCESS;
 564                 case '?':
 565                         return EXIT_FAILURE;
 566                 default:
 567                         assert_not_reached("Unknown option");
 568                 }
 569
 570         if (!update && !test) {
 571                 log_error("Either --update or --test must be used");
 572                 return EXIT_FAILURE;
 573         }
 574
 575         if (update) {
 576                 char **files, **f;
 577                 _cleanup_free_ char *hwdb_bin = NULL;
 578
 579                 trie = calloc(sizeof(struct trie), 1);
 580                 if (!trie) {
 581                         rc = EXIT_FAILURE;
 582                         goto out;
 583                 }
 584
 585                 /* string store */
 586                 trie->strings = strbuf_new();
 587                 if (!trie->strings) {
 588                         rc = EXIT_FAILURE;
 589                         goto out;
 590                 }
 591
 592                 /* index */
 593                 trie->root = calloc(sizeof(struct trie_node), 1);
 594                 if (!trie->root) {
 595                         rc = EXIT_FAILURE;
 596                         goto out;
 597                 }
 598                 trie->nodes_count++;
 599
 600                 err = conf_files_list_strv(&files, ".hwdb", root, conf_file_dirs);
 601                 if (err < 0) {
 602                         log_error("failed to enumerate hwdb files: %s\n", strerror(-err));
 603                         rc = EXIT_FAILURE;
 604                         goto out;
 605                 }
 606                 STRV_FOREACH(f, files) {
 607                         log_debug("reading file '%s'", *f);
 608                         import_file(udev, trie, *f);
 609                 }
 610                 strv_free(files);
 611
 612                 strbuf_complete(trie->strings);
 613
 614                 log_debug("=== trie in-memory ===\n");
 615                 log_debug("nodes:            %8zu bytes (%8zu)\n",
 616                           trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);
 617                 log_debug("children arrays:  %8zu bytes (%8zu)\n",
 618                           trie->children_count * sizeof(struct trie_child_entry), trie->children_count);
 619                 log_debug("values arrays:    %8zu bytes (%8zu)\n",
 620                           trie->values_count * sizeof(struct trie_value_entry), trie->values_count);
 621                 log_debug("strings:          %8zu bytes\n",
 622                           trie->strings->len);
 623                 log_debug("strings incoming: %8zu bytes (%8zu)\n",
 624                           trie->strings->in_len, trie->strings->in_count);
 625                 log_debug("strings dedup'ed: %8zu bytes (%8zu)\n",
 626                           trie->strings->dedup_len, trie->strings->dedup_count);
 627
 628                 if (asprintf(&hwdb_bin, "%s/etc/udev/hwdb.bin", root) < 0) {
 629                         rc = EXIT_FAILURE;
 630                         goto out;
 631                 }
 632                 mkdir_parents(hwdb_bin, 0755);
 633                 err = trie_store(trie, hwdb_bin);
 634                 if (err < 0) {
 635                         log_error("Failure writing database %s: %s", hwdb_bin, strerror(-err));
 636                         rc = EXIT_FAILURE;
 637                 }
 638         }
 639
 640         if (test) {
 641                 struct udev_hwdb *hwdb = udev_hwdb_new(udev);
 642
 643                 if (hwdb) {
 644                         struct udev_list_entry *entry;
 645
 646                         udev_list_entry_foreach(entry, udev_hwdb_get_properties_list_entry(hwdb, test, 0))
 647                                 printf("%s=%s\n", udev_list_entry_get_name(entry), udev_list_entry_get_value(entry));
 648                         udev_hwdb_unref(hwdb);
 649                 }
 650         }
 651 out:
 652         if (trie) {
 653                 if (trie->root)
 654                         trie_node_cleanup(trie->root);
 655                 strbuf_cleanup(trie->strings);
 656                 free(trie);
 657         }
 658         return rc;
 659 }
 660
 661 const struct udevadm_cmd udevadm_hwdb = {
 662         .name = "hwdb",
 663         .cmd = adm_hwdb,
 664         .help = "maintain the hardware database index",
 665 };