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 <getopt.h>
  22 #include <string.h>
  23 #include <ctype.h>
  24
  25 #include "util.h"
  26 #include "strbuf.h"
  27 #include "conf-files.h"
  28
  29 #include "udev.h"
  30 #include "hwdb-internal.h"
  31 #include "hwdb-util.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         "/run/udev/hwdb.d",
  41         UDEVLIBEXECDIR "/hwdb.d",
  42         NULL
  43 };
  44
  45 /* in-memory trie objects */
  46 struct trie {
  47         struct trie_node *root;
  48         struct strbuf *strings;
  49
  50         size_t nodes_count;
  51         size_t children_count;
  52         size_t values_count;
  53 };
  54
  55 struct trie_node {
  56         /* prefix, common part for all children of this node */
  57         size_t prefix_off;
  58
  59         /* sorted array of pointers to children nodes */
  60         struct trie_child_entry *children;
  61         uint8_t children_count;
  62
  63         /* sorted array of key/value pairs */
  64         struct trie_value_entry *values;
  65         size_t values_count;
  66 };
  67
  68 /* children array item with char (0-255) index */
  69 struct trie_child_entry {
  70         uint8_t c;
  71         struct trie_node *child;
  72 };
  73
  74 /* value array item with key/value pairs */
  75 struct trie_value_entry {
  76         size_t key_off;
  77         size_t value_off;
  78 };
  79
  80 static int trie_children_cmp(const void *v1, const void *v2) {
  81         const struct trie_child_entry *n1 = v1;
  82         const struct trie_child_entry *n2 = v2;
  83
  84         return n1->c - n2->c;
  85 }
  86
  87 static int node_add_child(struct trie *trie, struct trie_node *node, struct trie_node *node_child, uint8_t c) {
  88         struct trie_child_entry *child;
  89
  90         /* extend array, add new entry, sort for bisection */
  91         child = realloc(node->children, (node->children_count + 1) * sizeof(struct trie_child_entry));
  92         if (!child)
  93                 return -ENOMEM;
  94
  95         node->children = child;
  96         trie->children_count++;
  97         node->children[node->children_count].c = c;
  98         node->children[node->children_count].child = node_child;
  99         node->children_count++;
 100         qsort(node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
 101         trie->nodes_count++;
 102
 103         return 0;
 104 }
 105
 106 static struct trie_node *node_lookup(const struct trie_node *node, uint8_t c) {
 107         struct trie_child_entry *child;
 108         struct trie_child_entry search;
 109
 110         search.c = c;
 111         child = bsearch(&search, node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
 112         if (child)
 113                 return child->child;
 114         return NULL;
 115 }
 116
 117 static void trie_node_cleanup(struct trie_node *node) {
 118         size_t i;
 119
 120         for (i = 0; i < node->children_count; i++)
 121                 trie_node_cleanup(node->children[i].child);
 122         free(node->children);
 123         free(node->values);
 124         free(node);
 125 }
 126
 127 static int trie_values_cmp(const void *v1, const void *v2, void *arg) {
 128         const struct trie_value_entry *val1 = v1;
 129         const struct trie_value_entry *val2 = v2;
 130         struct trie *trie = arg;
 131
 132         return strcmp(trie->strings->buf + val1->key_off,
 133                       trie->strings->buf + val2->key_off);
 134 }
 135
 136 static int trie_node_add_value(struct trie *trie, struct trie_node *node,
 137                           const char *key, const char *value) {
 138         ssize_t k, v;
 139         struct trie_value_entry *val;
 140
 141         k = strbuf_add_string(trie->strings, key, strlen(key));
 142         if (k < 0)
 143                 return k;
 144         v = strbuf_add_string(trie->strings, value, strlen(value));
 145         if (v < 0)
 146                 return v;
 147
 148         if (node->values_count) {
 149                 struct trie_value_entry search = {
 150                         .key_off = k,
 151                         .value_off = v,
 152                 };
 153
 154                 val = xbsearch_r(&search, node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
 155                 if (val) {
 156                         /* replace existing earlier key with new value */
 157                         val->value_off = v;
 158                         return 0;
 159                 }
 160         }
 161
 162         /* extend array, add new entry, sort for bisection */
 163         val = realloc(node->values, (node->values_count + 1) * sizeof(struct trie_value_entry));
 164         if (!val)
 165                 return -ENOMEM;
 166         trie->values_count++;
 167         node->values = val;
 168         node->values[node->values_count].key_off = k;
 169         node->values[node->values_count].value_off = v;
 170         node->values_count++;
 171         qsort_r(node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
 172         return 0;
 173 }
 174
 175 static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,
 176                        const char *key, const char *value) {
 177         size_t i = 0;
 178         int err = 0;
 179
 180         for (;;) {
 181                 size_t p;
 182                 uint8_t c;
 183                 struct trie_node *child;
 184
 185                 for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {
 186                         _cleanup_free_ char *s = NULL;
 187                         ssize_t off;
 188                         _cleanup_free_ struct trie_node *new_child = NULL;
 189
 190                         if (c == search[i + p])
 191                                 continue;
 192
 193                         /* split node */
 194                         new_child = new0(struct trie_node, 1);
 195                         if (!new_child)
 196                                 return -ENOMEM;
 197
 198                         /* move values from parent to child */
 199                         new_child->prefix_off = node->prefix_off + p+1;
 200                         new_child->children = node->children;
 201                         new_child->children_count = node->children_count;
 202                         new_child->values = node->values;
 203                         new_child->values_count = node->values_count;
 204
 205                         /* update parent; use strdup() because the source gets realloc()d */
 206                         s = strndup(trie->strings->buf + node->prefix_off, p);
 207                         if (!s)
 208                                 return -ENOMEM;
 209
 210                         off = strbuf_add_string(trie->strings, s, p);
 211                         if (off < 0)
 212                                 return off;
 213
 214                         node->prefix_off = off;
 215                         node->children = NULL;
 216                         node->children_count = 0;
 217                         node->values = NULL;
 218                         node->values_count = 0;
 219                         err = node_add_child(trie, node, new_child, c);
 220                         if (err)
 221                                 return err;
 222
 223                         new_child = NULL; /* avoid cleanup */
 224                         break;
 225                 }
 226                 i += p;
 227
 228                 c = search[i];
 229                 if (c == '\0')
 230                         return trie_node_add_value(trie, node, key, value);
 231
 232                 child = node_lookup(node, c);
 233                 if (!child) {
 234                         ssize_t off;
 235
 236                         /* new child */
 237                         child = new0(struct trie_node, 1);
 238                         if (!child)
 239                                 return -ENOMEM;
 240
 241                         off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));
 242                         if (off < 0) {
 243                                 free(child);
 244                                 return off;
 245                         }
 246
 247                         child->prefix_off = off;
 248                         err = node_add_child(trie, node, child, c);
 249                         if (err) {
 250                                 free(child);
 251                                 return err;
 252                         }
 253
 254                         return trie_node_add_value(trie, child, key, value);
 255                 }
 256
 257                 node = child;
 258                 i++;
 259         }
 260 }
 261
 262 struct trie_f {
 263         FILE *f;
 264         struct trie *trie;
 265         uint64_t strings_off;
 266
 267         uint64_t nodes_count;
 268         uint64_t children_count;
 269         uint64_t values_count;
 270 };
 271
 272 /* calculate the storage space for the nodes, children arrays, value arrays */
 273 static void trie_store_nodes_size(struct trie_f *trie, struct trie_node *node) {
 274         uint64_t i;
 275
 276         for (i = 0; i < node->children_count; i++)
 277                 trie_store_nodes_size(trie, node->children[i].child);
 278
 279         trie->strings_off += sizeof(struct trie_node_f);
 280         for (i = 0; i < node->children_count; i++)
 281                 trie->strings_off += sizeof(struct trie_child_entry_f);
 282         for (i = 0; i < node->values_count; i++)
 283                 trie->strings_off += sizeof(struct trie_value_entry_f);
 284 }
 285
 286 static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node) {
 287         uint64_t i;
 288         struct trie_node_f n = {
 289                 .prefix_off = htole64(trie->strings_off + node->prefix_off),
 290                 .children_count = node->children_count,
 291                 .values_count = htole64(node->values_count),
 292         };
 293         struct trie_child_entry_f *children = NULL;
 294         int64_t node_off;
 295
 296         if (node->children_count) {
 297                 children = new0(struct trie_child_entry_f, node->children_count);
 298                 if (!children)
 299                         return -ENOMEM;
 300         }
 301
 302         /* post-order recursion */
 303         for (i = 0; i < node->children_count; i++) {
 304                 int64_t child_off;
 305
 306                 child_off = trie_store_nodes(trie, node->children[i].child);
 307                 if (child_off < 0) {
 308                         free(children);
 309                         return child_off;
 310                 }
 311                 children[i].c = node->children[i].c;
 312                 children[i].child_off = htole64(child_off);
 313         }
 314
 315         /* write node */
 316         node_off = ftello(trie->f);
 317         fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);
 318         trie->nodes_count++;
 319
 320         /* append children array */
 321         if (node->children_count) {
 322                 fwrite(children, sizeof(struct trie_child_entry_f), node->children_count, trie->f);
 323                 trie->children_count += node->children_count;
 324                 free(children);
 325         }
 326
 327         /* append values array */
 328         for (i = 0; i < node->values_count; i++) {
 329                 struct trie_value_entry_f v = {
 330                         .key_off = htole64(trie->strings_off + node->values[i].key_off),
 331                         .value_off = htole64(trie->strings_off + node->values[i].value_off),
 332                 };
 333
 334                 fwrite(&v, sizeof(struct trie_value_entry_f), 1, trie->f);
 335                 trie->values_count++;
 336         }
 337
 338         return node_off;
 339 }
 340
 341 static int trie_store(struct trie *trie, const char *filename) {
 342         struct trie_f t = {
 343                 .trie = trie,
 344         };
 345         _cleanup_free_ char *filename_tmp = NULL;
 346         int64_t pos;
 347         int64_t root_off;
 348         int64_t size;
 349         struct trie_header_f h = {
 350                 .signature = HWDB_SIG,
 351                 .tool_version = htole64(atoi(VERSION)),
 352                 .header_size = htole64(sizeof(struct trie_header_f)),
 353                 .node_size = htole64(sizeof(struct trie_node_f)),
 354                 .child_entry_size = htole64(sizeof(struct trie_child_entry_f)),
 355                 .value_entry_size = htole64(sizeof(struct trie_value_entry_f)),
 356         };
 357         int err;
 358
 359         /* calculate size of header, nodes, children entries, value entries */
 360         t.strings_off = sizeof(struct trie_header_f);
 361         trie_store_nodes_size(&t, trie->root);
 362
 363         err = fopen_temporary(filename , &t.f, &filename_tmp);
 364         if (err < 0)
 365                 return err;
 366         fchmod(fileno(t.f), 0444);
 367
 368         /* write nodes */
 369         err = fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET);
 370         if (err < 0) {
 371                 fclose(t.f);
 372                 unlink_noerrno(filename_tmp);
 373                 return -errno;
 374         }
 375         root_off = trie_store_nodes(&t, trie->root);
 376         h.nodes_root_off = htole64(root_off);
 377         pos = ftello(t.f);
 378         h.nodes_len = htole64(pos - sizeof(struct trie_header_f));
 379
 380         /* write string buffer */
 381         fwrite(trie->strings->buf, trie->strings->len, 1, t.f);
 382         h.strings_len = htole64(trie->strings->len);
 383
 384         /* write header */
 385         size = ftello(t.f);
 386         h.file_size = htole64(size);
 387         err = fseeko(t.f, 0, SEEK_SET);
 388         if (err < 0) {
 389                 fclose(t.f);
 390                 unlink_noerrno(filename_tmp);
 391                 return -errno;
 392         }
 393         fwrite(&h, sizeof(struct trie_header_f), 1, t.f);
 394         err = ferror(t.f);
 395         if (err)
 396                 err = -errno;
 397         fclose(t.f);
 398         if (err < 0 || rename(filename_tmp, filename) < 0) {
 399                 unlink_noerrno(filename_tmp);
 400                 return err < 0 ? err : -errno;
 401         }
 402
 403         log_debug("=== trie on-disk ===");
 404         log_debug("size:             %8"PRIi64" bytes", size);
 405         log_debug("header:           %8zu bytes", sizeof(struct trie_header_f));
 406         log_debug("nodes:            %8"PRIu64" bytes (%8"PRIu64")",
 407                   t.nodes_count * sizeof(struct trie_node_f), t.nodes_count);
 408         log_debug("child pointers:   %8"PRIu64" bytes (%8"PRIu64")",
 409                   t.children_count * sizeof(struct trie_child_entry_f), t.children_count);
 410         log_debug("value pointers:   %8"PRIu64" bytes (%8"PRIu64")",
 411                   t.values_count * sizeof(struct trie_value_entry_f), t.values_count);
 412         log_debug("string store:     %8zu bytes", trie->strings->len);
 413         log_debug("strings start:    %8"PRIu64, t.strings_off);
 414
 415         return 0;
 416 }
 417
 418 static int insert_data(struct trie *trie, struct udev_list *match_list,
 419                        char *line, const char *filename) {
 420         char *value;
 421         struct udev_list_entry *entry;
 422
 423         value = strchr(line, '=');
 424         if (!value) {
 425                 log_error("Error, key/value pair expected but got '%s' in '%s':", line, filename);
 426                 return -EINVAL;
 427         }
 428
 429         value[0] = '\0';
 430         value++;
 431
 432         /* libudev requires properties to start with a space */
 433         while (isblank(line[0]) && isblank(line[1]))
 434                 line++;
 435
 436         if (line[0] == '\0' || value[0] == '\0') {
 437                 log_error("Error, empty key or value '%s' in '%s':", line, filename);
 438                 return -EINVAL;
 439         }
 440
 441         udev_list_entry_foreach(entry, udev_list_get_entry(match_list))
 442                 trie_insert(trie, trie->root, udev_list_entry_get_name(entry), line, value);
 443
 444         return 0;
 445 }
 446
 447 static int import_file(struct udev *udev, struct trie *trie, const char *filename) {
 448         enum {
 449                 HW_MATCH,
 450                 HW_DATA,
 451                 HW_NONE,
 452         } state = HW_NONE;
 453         FILE *f;
 454         char line[LINE_MAX];
 455         struct udev_list match_list;
 456
 457         udev_list_init(udev, &match_list, false);
 458
 459         f = fopen(filename, "re");
 460         if (f == NULL)
 461                 return -errno;
 462
 463         while (fgets(line, sizeof(line), f)) {
 464                 size_t len;
 465                 char *pos;
 466
 467                 /* comment line */
 468                 if (line[0] == '#')
 469                         continue;
 470
 471                 /* strip trailing comment */
 472                 pos = strchr(line, '#');
 473                 if (pos)
 474                         pos[0] = '\0';
 475
 476                 /* strip trailing whitespace */
 477                 len = strlen(line);
 478                 while (len > 0 && isspace(line[len-1]))
 479                         len--;
 480                 line[len] = '\0';
 481
 482                 switch (state) {
 483                 case HW_NONE:
 484                         if (len == 0)
 485                                 break;
 486
 487                         if (line[0] == ' ') {
 488                                 log_error("Error, MATCH expected but got '%s' in '%s':", line, filename);
 489                                 break;
 490                         }
 491
 492                         /* start of record, first match */
 493                         state = HW_MATCH;
 494                         udev_list_entry_add(&match_list, line, NULL);
 495                         break;
 496
 497                 case HW_MATCH:
 498                         if (len == 0) {
 499                                 log_error("Error, DATA expected but got empty line in '%s':", filename);
 500                                 state = HW_NONE;
 501                                 udev_list_cleanup(&match_list);
 502                                 break;
 503                         }
 504
 505                         /* another match */
 506                         if (line[0] != ' ') {
 507                                 udev_list_entry_add(&match_list, line, NULL);
 508                                 break;
 509                         }
 510
 511                         /* first data */
 512                         state = HW_DATA;
 513                         insert_data(trie, &match_list, line, filename);
 514                         break;
 515
 516                 case HW_DATA:
 517                         /* end of record */
 518                         if (len == 0) {
 519                                 state = HW_NONE;
 520                                 udev_list_cleanup(&match_list);
 521                                 break;
 522                         }
 523
 524                         if (line[0] != ' ') {
 525                                 log_error("Error, DATA expected but got '%s' in '%s':", line, filename);
 526                                 state = HW_NONE;
 527                                 udev_list_cleanup(&match_list);
 528                                 break;
 529                         }
 530
 531                         insert_data(trie, &match_list, line, filename);
 532                         break;
 533                 };
 534         }
 535
 536         fclose(f);
 537         udev_list_cleanup(&match_list);
 538         return 0;
 539 }
 540
 541 static void help(void) {
 542         printf("Usage: udevadm hwdb OPTIONS\n"
 543                "  -u,--update          update the hardware database\n"
 544                "  --usr                generate in " UDEVLIBEXECDIR " instead of /etc/udev\n"
 545                "  -t,--test=MODALIAS   query database and print result\n"
 546                "  -r,--root=PATH       alternative root path in the filesystem\n"
 547                "  -h,--help\n\n");
 548 }
 549
 550 static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {
 551         enum {
 552                 ARG_USR = 0x100,
 553         };
 554
 555         static const struct option options[] = {
 556                 { "update", no_argument,       NULL, 'u' },
 557                 { "usr",    no_argument,       NULL, ARG_USR },
 558                 { "test",   required_argument, NULL, 't' },
 559                 { "root",   required_argument, NULL, 'r' },
 560                 { "help",   no_argument,       NULL, 'h' },
 561                 {}
 562         };
 563         const char *test = NULL;
 564         const char *root = "";
 565         const char *hwdb_bin_dir = "/etc/udev";
 566         bool update = false;
 567         struct trie *trie = NULL;
 568         int err, c;
 569         int rc = EXIT_SUCCESS;
 570
 571         while ((c = getopt_long(argc, argv, "ut:r:h", options, NULL)) >= 0)
 572                 switch(c) {
 573                 case 'u':
 574                         update = true;
 575                         break;
 576                 case ARG_USR:
 577                         hwdb_bin_dir = UDEVLIBEXECDIR;
 578                         break;
 579                 case 't':
 580                         test = optarg;
 581                         break;
 582                 case 'r':
 583                         root = optarg;
 584                         break;
 585                 case 'h':
 586                         help();
 587                         return EXIT_SUCCESS;
 588                 case '?':
 589                         return EXIT_FAILURE;
 590                 default:
 591                         assert_not_reached("Unknown option");
 592                 }
 593
 594         if (!update && !test) {
 595                 log_error("Either --update or --test must be used");
 596                 return EXIT_FAILURE;
 597         }
 598
 599         if (update) {
 600                 char **files, **f;
 601                 _cleanup_free_ char *hwdb_bin = NULL;
 602
 603                 trie = new0(struct trie, 1);
 604                 if (!trie) {
 605                         rc = EXIT_FAILURE;
 606                         goto out;
 607                 }
 608
 609                 /* string store */
 610                 trie->strings = strbuf_new();
 611                 if (!trie->strings) {
 612                         rc = EXIT_FAILURE;
 613                         goto out;
 614                 }
 615
 616                 /* index */
 617                 trie->root = new0(struct trie_node, 1);
 618                 if (!trie->root) {
 619                         rc = EXIT_FAILURE;
 620                         goto out;
 621                 }
 622                 trie->nodes_count++;
 623
 624                 err = conf_files_list_strv(&files, ".hwdb", root, conf_file_dirs);
 625                 if (err < 0) {
 626                         log_error_errno(err, "failed to enumerate hwdb files: %m");
 627                         rc = EXIT_FAILURE;
 628                         goto out;
 629                 }
 630                 STRV_FOREACH(f, files) {
 631                         log_debug("reading file '%s'", *f);
 632                         import_file(udev, trie, *f);
 633                 }
 634                 strv_free(files);
 635
 636                 strbuf_complete(trie->strings);
 637
 638                 log_debug("=== trie in-memory ===");
 639                 log_debug("nodes:            %8zu bytes (%8zu)",
 640                           trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);
 641                 log_debug("children arrays:  %8zu bytes (%8zu)",
 642                           trie->children_count * sizeof(struct trie_child_entry), trie->children_count);
 643                 log_debug("values arrays:    %8zu bytes (%8zu)",
 644                           trie->values_count * sizeof(struct trie_value_entry), trie->values_count);
 645                 log_debug("strings:          %8zu bytes",
 646                           trie->strings->len);
 647                 log_debug("strings incoming: %8zu bytes (%8zu)",
 648                           trie->strings->in_len, trie->strings->in_count);
 649                 log_debug("strings dedup'ed: %8zu bytes (%8zu)",
 650                           trie->strings->dedup_len, trie->strings->dedup_count);
 651
 652                 hwdb_bin = strjoin(root, "/", hwdb_bin_dir, "/hwdb.bin", NULL);
 653                 if (!hwdb_bin) {
 654                         rc = EXIT_FAILURE;
 655                         goto out;
 656                 }
 657                 mkdir_parents(hwdb_bin, 0755);
 658                 err = trie_store(trie, hwdb_bin);
 659                 if (err < 0) {
 660                         log_error_errno(err, "Failure writing database %s: %m", hwdb_bin);
 661                         rc = EXIT_FAILURE;
 662                 }
 663         }
 664
 665         if (test) {
 666                 _cleanup_hwdb_unref_ sd_hwdb *hwdb = NULL;
 667                 int r;
 668
 669                 r = sd_hwdb_new(&hwdb);
 670                 if (r >= 0) {
 671                         const char *key, *value;
 672
 673                         SD_HWDB_FOREACH_PROPERTY(hwdb, test, key, value)
 674                                 printf("%s=%s\n", key, value);
 675                 }
 676         }
 677 out:
 678         if (trie) {
 679                 if (trie->root)
 680                         trie_node_cleanup(trie->root);
 681                 strbuf_cleanup(trie->strings);
 682                 free(trie);
 683         }
 684         return rc;
 685 }
 686
 687 const struct udevadm_cmd udevadm_hwdb = {
 688         .name = "hwdb",
 689         .cmd = adm_hwdb,
 690 };