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 <ctype.h>
  21 #include <getopt.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #include "alloc-util.h"
  26 #include "conf-files.h"
  27 #include "fileio.h"
  28 #include "fs-util.h"
  29 #include "hwdb-internal.h"
  30 #include "hwdb-util.h"
  31 #include "label.h"
  32 #include "mkdir.h"
  33 #include "strbuf.h"
  34 #include "string-util.h"
  35 #include "udev.h"
  36 #include "util.h"
  37
  38 /*
  39  * Generic udev properties, key/value database based on modalias strings.
  40  * Uses a Patricia/radix trie to index all matches for efficient lookup.
  41  */
  42
  43 static const char * const conf_file_dirs[] = {
  44         "/etc/udev/hwdb.d",
  45         UDEVLIBEXECDIR "/hwdb.d",
  46         NULL
  47 };
  48
  49 /* in-memory trie objects */
  50 struct trie {
  51         struct trie_node *root;
  52         struct strbuf *strings;
  53
  54         size_t nodes_count;
  55         size_t children_count;
  56         size_t values_count;
  57 };
  58
  59 struct trie_node {
  60         /* prefix, common part for all children of this node */
  61         size_t prefix_off;
  62
  63         /* sorted array of pointers to children nodes */
  64         struct trie_child_entry *children;
  65         uint8_t children_count;
  66
  67         /* sorted array of key/value pairs */
  68         struct trie_value_entry *values;
  69         size_t values_count;
  70 };
  71
  72 /* children array item with char (0-255) index */
  73 struct trie_child_entry {
  74         uint8_t c;
  75         struct trie_node *child;
  76 };
  77
  78 /* value array item with key/value pairs */
  79 struct trie_value_entry {
  80         size_t key_off;
  81         size_t value_off;
  82 };
  83
  84 static int trie_children_cmp(const void *v1, const void *v2) {
  85         const struct trie_child_entry *n1 = v1;
  86         const struct trie_child_entry *n2 = v2;
  87
  88         return n1->c - n2->c;
  89 }
  90
  91 static int node_add_child(struct trie *trie, struct trie_node *node, struct trie_node *node_child, uint8_t c) {
  92         struct trie_child_entry *child;
  93
  94         /* extend array, add new entry, sort for bisection */
  95         child = realloc(node->children, (node->children_count + 1) * sizeof(struct trie_child_entry));
  96         if (!child)
  97                 return -ENOMEM;
  98
  99         node->children = child;
 100         trie->children_count++;
 101         node->children[node->children_count].c = c;
 102         node->children[node->children_count].child = node_child;
 103         node->children_count++;
 104         qsort(node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
 105         trie->nodes_count++;
 106
 107         return 0;
 108 }
 109
 110 static struct trie_node *node_lookup(const struct trie_node *node, uint8_t c) {
 111         struct trie_child_entry *child;
 112         struct trie_child_entry search;
 113
 114         search.c = c;
 115         child = bsearch(&search, node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
 116         if (child)
 117                 return child->child;
 118         return NULL;
 119 }
 120
 121 static void trie_node_cleanup(struct trie_node *node) {
 122         size_t i;
 123
 124         for (i = 0; i < node->children_count; i++)
 125                 trie_node_cleanup(node->children[i].child);
 126         free(node->children);
 127         free(node->values);
 128         free(node);
 129 }
 130
 131 static int trie_values_cmp(const void *v1, const void *v2, void *arg) {
 132         const struct trie_value_entry *val1 = v1;
 133         const struct trie_value_entry *val2 = v2;
 134         struct trie *trie = arg;
 135
 136         return strcmp(trie->strings->buf + val1->key_off,
 137                       trie->strings->buf + val2->key_off);
 138 }
 139
 140 static int trie_node_add_value(struct trie *trie, struct trie_node *node,
 141                           const char *key, const char *value) {
 142         ssize_t k, v;
 143         struct trie_value_entry *val;
 144
 145         k = strbuf_add_string(trie->strings, key, strlen(key));
 146         if (k < 0)
 147                 return k;
 148         v = strbuf_add_string(trie->strings, value, strlen(value));
 149         if (v < 0)
 150                 return v;
 151
 152         if (node->values_count) {
 153                 struct trie_value_entry search = {
 154                         .key_off = k,
 155                         .value_off = v,
 156                 };
 157
 158                 val = xbsearch_r(&search, node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
 159                 if (val) {
 160                         /* replace existing earlier key with new value */
 161                         val->value_off = v;
 162                         return 0;
 163                 }
 164         }
 165
 166         /* extend array, add new entry, sort for bisection */
 167         val = realloc(node->values, (node->values_count + 1) * sizeof(struct trie_value_entry));
 168         if (!val)
 169                 return -ENOMEM;
 170         trie->values_count++;
 171         node->values = val;
 172         node->values[node->values_count].key_off = k;
 173         node->values[node->values_count].value_off = v;
 174         node->values_count++;
 175         qsort_r(node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
 176         return 0;
 177 }
 178
 179 static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,
 180                        const char *key, const char *value) {
 181         size_t i = 0;
 182         int err = 0;
 183
 184         for (;;) {
 185                 size_t p;
 186                 uint8_t c;
 187                 struct trie_node *child;
 188
 189                 for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {
 190                         _cleanup_free_ char *s = NULL;
 191                         ssize_t off;
 192                         _cleanup_free_ struct trie_node *new_child = NULL;
 193
 194                         if (c == search[i + p])
 195                                 continue;
 196
 197                         /* split node */
 198                         new_child = new0(struct trie_node, 1);
 199                         if (!new_child)
 200                                 return -ENOMEM;
 201
 202                         /* move values from parent to child */
 203                         new_child->prefix_off = node->prefix_off + p+1;
 204                         new_child->children = node->children;
 205                         new_child->children_count = node->children_count;
 206                         new_child->values = node->values;
 207                         new_child->values_count = node->values_count;
 208
 209                         /* update parent; use strdup() because the source gets realloc()d */
 210                         s = strndup(trie->strings->buf + node->prefix_off, p);
 211                         if (!s)
 212                                 return -ENOMEM;
 213
 214                         off = strbuf_add_string(trie->strings, s, p);
 215                         if (off < 0)
 216                                 return off;
 217
 218                         node->prefix_off = off;
 219                         node->children = NULL;
 220                         node->children_count = 0;
 221                         node->values = NULL;
 222                         node->values_count = 0;
 223                         err = node_add_child(trie, node, new_child, c);
 224                         if (err)
 225                                 return err;
 226
 227                         new_child = NULL; /* avoid cleanup */
 228                         break;
 229                 }
 230                 i += p;
 231
 232                 c = search[i];
 233                 if (c == '\0')
 234                         return trie_node_add_value(trie, node, key, value);
 235
 236                 child = node_lookup(node, c);
 237                 if (!child) {
 238                         ssize_t off;
 239
 240                         /* new child */
 241                         child = new0(struct trie_node, 1);
 242                         if (!child)
 243                                 return -ENOMEM;
 244
 245                         off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));
 246                         if (off < 0) {
 247                                 free(child);
 248                                 return off;
 249                         }
 250
 251                         child->prefix_off = off;
 252                         err = node_add_child(trie, node, child, c);
 253                         if (err) {
 254                                 free(child);
 255                                 return err;
 256                         }
 257
 258                         return trie_node_add_value(trie, child, key, value);
 259                 }
 260
 261                 node = child;
 262                 i++;
 263         }
 264 }
 265
 266 struct trie_f {
 267         FILE *f;
 268         struct trie *trie;
 269         uint64_t strings_off;
 270
 271         uint64_t nodes_count;
 272         uint64_t children_count;
 273         uint64_t values_count;
 274 };
 275
 276 /* calculate the storage space for the nodes, children arrays, value arrays */
 277 static void trie_store_nodes_size(struct trie_f *trie, struct trie_node *node) {
 278         uint64_t i;
 279
 280         for (i = 0; i < node->children_count; i++)
 281                 trie_store_nodes_size(trie, node->children[i].child);
 282
 283         trie->strings_off += sizeof(struct trie_node_f);
 284         for (i = 0; i < node->children_count; i++)
 285                 trie->strings_off += sizeof(struct trie_child_entry_f);
 286         for (i = 0; i < node->values_count; i++)
 287                 trie->strings_off += sizeof(struct trie_value_entry_f);
 288 }
 289
 290 static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node) {
 291         uint64_t i;
 292         struct trie_node_f n = {
 293                 .prefix_off = htole64(trie->strings_off + node->prefix_off),
 294                 .children_count = node->children_count,
 295                 .values_count = htole64(node->values_count),
 296         };
 297         struct trie_child_entry_f *children = NULL;
 298         int64_t node_off;
 299
 300         if (node->children_count) {
 301                 children = new0(struct trie_child_entry_f, node->children_count);
 302                 if (!children)
 303                         return -ENOMEM;
 304         }
 305
 306         /* post-order recursion */
 307         for (i = 0; i < node->children_count; i++) {
 308                 int64_t child_off;
 309
 310                 child_off = trie_store_nodes(trie, node->children[i].child);
 311                 if (child_off < 0) {
 312                         free(children);
 313                         return child_off;
 314                 }
 315                 children[i].c = node->children[i].c;
 316                 children[i].child_off = htole64(child_off);
 317         }
 318
 319         /* write node */
 320         node_off = ftello(trie->f);
 321         fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);
 322         trie->nodes_count++;
 323
 324         /* append children array */
 325         if (node->children_count) {
 326                 fwrite(children, sizeof(struct trie_child_entry_f), node->children_count, trie->f);
 327                 trie->children_count += node->children_count;
 328                 free(children);
 329         }
 330
 331         /* append values array */
 332         for (i = 0; i < node->values_count; i++) {
 333                 struct trie_value_entry_f v = {
 334                         .key_off = htole64(trie->strings_off + node->values[i].key_off),
 335                         .value_off = htole64(trie->strings_off + node->values[i].value_off),
 336                 };
 337
 338                 fwrite(&v, sizeof(struct trie_value_entry_f), 1, trie->f);
 339                 trie->values_count++;
 340         }
 341
 342         return node_off;
 343 }
 344
 345 static int trie_store(struct trie *trie, const char *filename) {
 346         struct trie_f t = {
 347                 .trie = trie,
 348         };
 349         _cleanup_free_ char *filename_tmp = NULL;
 350         int64_t pos;
 351         int64_t root_off;
 352         int64_t size;
 353         struct trie_header_f h = {
 354                 .signature = HWDB_SIG,
 355                 .tool_version = htole64(atoi(PACKAGE_VERSION)),
 356                 .header_size = htole64(sizeof(struct trie_header_f)),
 357                 .node_size = htole64(sizeof(struct trie_node_f)),
 358                 .child_entry_size = htole64(sizeof(struct trie_child_entry_f)),
 359                 .value_entry_size = htole64(sizeof(struct trie_value_entry_f)),
 360         };
 361         int err;
 362
 363         /* calculate size of header, nodes, children entries, value entries */
 364         t.strings_off = sizeof(struct trie_header_f);
 365         trie_store_nodes_size(&t, trie->root);
 366
 367         err = fopen_temporary(filename, &t.f, &filename_tmp);
 368         if (err < 0)
 369                 return err;
 370         fchmod(fileno(t.f), 0444);
 371
 372         /* write nodes */
 373         if (fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET) < 0)
 374                 goto error_fclose;
 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         if (fseeko(t.f, 0, SEEK_SET < 0))
 388                 goto error_fclose;
 389         fwrite(&h, sizeof(struct trie_header_f), 1, t.f);
 390
 391         if (ferror(t.f))
 392                 goto error_fclose;
 393         if (fflush(t.f) < 0)
 394                 goto error_fclose;
 395         if (fsync(fileno(t.f)) < 0)
 396                 goto error_fclose;
 397         if (rename(filename_tmp, filename) < 0)
 398                 goto error_fclose;
 399
 400         /* write succeeded */
 401         fclose(t.f);
 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  error_fclose:
 418         err = -errno;
 419         fclose(t.f);
 420         unlink(filename_tmp);
 421         return err;
 422 }
 423
 424 static int insert_data(struct trie *trie, struct udev_list *match_list,
 425                        char *line, const char *filename) {
 426         char *value;
 427         struct udev_list_entry *entry;
 428
 429         value = strchr(line, '=');
 430         if (!value) {
 431                 log_error("Error, key/value pair expected but got '%s' in '%s':", line, filename);
 432                 return -EINVAL;
 433         }
 434
 435         value[0] = '\0';
 436         value++;
 437
 438         /* libudev requires properties to start with a space */
 439         while (isblank(line[0]) && isblank(line[1]))
 440                 line++;
 441
 442         if (line[0] == '\0' || value[0] == '\0') {
 443                 log_error("Error, empty key or value '%s' in '%s':", line, filename);
 444                 return -EINVAL;
 445         }
 446
 447         udev_list_entry_foreach(entry, udev_list_get_entry(match_list))
 448                 trie_insert(trie, trie->root, udev_list_entry_get_name(entry), line, value);
 449
 450         return 0;
 451 }
 452
 453 static int import_file(struct udev *udev, struct trie *trie, const char *filename) {
 454         enum {
 455                 HW_MATCH,
 456                 HW_DATA,
 457                 HW_NONE,
 458         } state = HW_NONE;
 459         FILE *f;
 460         char line[LINE_MAX];
 461         struct udev_list match_list;
 462
 463         udev_list_init(udev, &match_list, false);
 464
 465         f = fopen(filename, "re");
 466         if (f == NULL)
 467                 return -errno;
 468
 469         while (fgets(line, sizeof(line), f)) {
 470                 size_t len;
 471                 char *pos;
 472
 473                 /* comment line */
 474                 if (line[0] == '#')
 475                         continue;
 476
 477                 /* strip trailing comment */
 478                 pos = strchr(line, '#');
 479                 if (pos)
 480                         pos[0] = '\0';
 481
 482                 /* strip trailing whitespace */
 483                 len = strlen(line);
 484                 while (len > 0 && isspace(line[len-1]))
 485                         len--;
 486                 line[len] = '\0';
 487
 488                 switch (state) {
 489                 case HW_NONE:
 490                         if (len == 0)
 491                                 break;
 492
 493                         if (line[0] == ' ') {
 494                                 log_error("Error, MATCH expected but got '%s' in '%s':", line, filename);
 495                                 break;
 496                         }
 497
 498                         /* start of record, first match */
 499                         state = HW_MATCH;
 500                         udev_list_entry_add(&match_list, line, NULL);
 501                         break;
 502
 503                 case HW_MATCH:
 504                         if (len == 0) {
 505                                 log_error("Error, DATA expected but got empty line in '%s':", filename);
 506                                 state = HW_NONE;
 507                                 udev_list_cleanup(&match_list);
 508                                 break;
 509                         }
 510
 511                         /* another match */
 512                         if (line[0] != ' ') {
 513                                 udev_list_entry_add(&match_list, line, NULL);
 514                                 break;
 515                         }
 516
 517                         /* first data */
 518                         state = HW_DATA;
 519                         insert_data(trie, &match_list, line, filename);
 520                         break;
 521
 522                 case HW_DATA:
 523                         /* end of record */
 524                         if (len == 0) {
 525                                 state = HW_NONE;
 526                                 udev_list_cleanup(&match_list);
 527                                 break;
 528                         }
 529
 530                         if (line[0] != ' ') {
 531                                 log_error("Error, DATA expected but got '%s' in '%s':", line, filename);
 532                                 state = HW_NONE;
 533                                 udev_list_cleanup(&match_list);
 534                                 break;
 535                         }
 536
 537                         insert_data(trie, &match_list, line, filename);
 538                         break;
 539                 };
 540         }
 541
 542         fclose(f);
 543         udev_list_cleanup(&match_list);
 544         return 0;
 545 }
 546
 547 static void help(void) {
 548         printf("Usage: udevadm hwdb OPTIONS\n"
 549                "  -u,--update          update the hardware database\n"
 550                "  --usr                generate in " UDEVLIBEXECDIR " instead of /etc/udev\n"
 551                "  -t,--test=MODALIAS   query database and print result\n"
 552                "  -r,--root=PATH       alternative root path in the filesystem\n"
 553                "  -h,--help\n\n");
 554 }
 555
 556 static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {
 557         enum {
 558                 ARG_USR = 0x100,
 559         };
 560
 561         static const struct option options[] = {
 562                 { "update", no_argument,       NULL, 'u' },
 563                 { "usr",    no_argument,       NULL, ARG_USR },
 564                 { "test",   required_argument, NULL, 't' },
 565                 { "root",   required_argument, NULL, 'r' },
 566                 { "help",   no_argument,       NULL, 'h' },
 567                 {}
 568         };
 569         const char *test = NULL;
 570         const char *root = "";
 571         const char *hwdb_bin_dir = "/etc/udev";
 572         bool update = false;
 573         struct trie *trie = NULL;
 574         int err, c;
 575         int rc = EXIT_SUCCESS;
 576
 577         while ((c = getopt_long(argc, argv, "ut:r:h", options, NULL)) >= 0)
 578                 switch(c) {
 579                 case 'u':
 580                         update = true;
 581                         break;
 582                 case ARG_USR:
 583                         hwdb_bin_dir = UDEVLIBEXECDIR;
 584                         break;
 585                 case 't':
 586                         test = optarg;
 587                         break;
 588                 case 'r':
 589                         root = optarg;
 590                         break;
 591                 case 'h':
 592                         help();
 593                         return EXIT_SUCCESS;
 594                 case '?':
 595                         return EXIT_FAILURE;
 596                 default:
 597                         assert_not_reached("Unknown option");
 598                 }
 599
 600         if (!update && !test) {
 601                 log_error("Either --update or --test must be used");
 602                 return EXIT_FAILURE;
 603         }
 604
 605         if (update) {
 606                 char **files, **f;
 607                 _cleanup_free_ char *hwdb_bin = NULL;
 608
 609                 trie = new0(struct trie, 1);
 610                 if (!trie) {
 611                         rc = EXIT_FAILURE;
 612                         goto out;
 613                 }
 614
 615                 /* string store */
 616                 trie->strings = strbuf_new();
 617                 if (!trie->strings) {
 618                         rc = EXIT_FAILURE;
 619                         goto out;
 620                 }
 621
 622                 /* index */
 623                 trie->root = new0(struct trie_node, 1);
 624                 if (!trie->root) {
 625                         rc = EXIT_FAILURE;
 626                         goto out;
 627                 }
 628                 trie->nodes_count++;
 629
 630                 err = conf_files_list_strv(&files, ".hwdb", root, 0, conf_file_dirs);
 631                 if (err < 0) {
 632                         log_error_errno(err, "failed to enumerate hwdb files: %m");
 633                         rc = EXIT_FAILURE;
 634                         goto out;
 635                 }
 636                 STRV_FOREACH(f, files) {
 637                         log_debug("reading file '%s'", *f);
 638                         import_file(udev, trie, *f);
 639                 }
 640                 strv_free(files);
 641
 642                 strbuf_complete(trie->strings);
 643
 644                 log_debug("=== trie in-memory ===");
 645                 log_debug("nodes:            %8zu bytes (%8zu)",
 646                           trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);
 647                 log_debug("children arrays:  %8zu bytes (%8zu)",
 648                           trie->children_count * sizeof(struct trie_child_entry), trie->children_count);
 649                 log_debug("values arrays:    %8zu bytes (%8zu)",
 650                           trie->values_count * sizeof(struct trie_value_entry), trie->values_count);
 651                 log_debug("strings:          %8zu bytes",
 652                           trie->strings->len);
 653                 log_debug("strings incoming: %8zu bytes (%8zu)",
 654                           trie->strings->in_len, trie->strings->in_count);
 655                 log_debug("strings dedup'ed: %8zu bytes (%8zu)",
 656                           trie->strings->dedup_len, trie->strings->dedup_count);
 657
 658                 hwdb_bin = strjoin(root, "/", hwdb_bin_dir, "/hwdb.bin");
 659                 if (!hwdb_bin) {
 660                         rc = EXIT_FAILURE;
 661                         goto out;
 662                 }
 663
 664                 mkdir_parents_label(hwdb_bin, 0755);
 665
 666                 err = trie_store(trie, hwdb_bin);
 667                 if (err < 0) {
 668                         log_error_errno(err, "Failure writing database %s: %m", hwdb_bin);
 669                         rc = EXIT_FAILURE;
 670                 }
 671
 672                 label_fix(hwdb_bin, false, false);
 673         }
 674
 675         if (test) {
 676                 _cleanup_(sd_hwdb_unrefp) sd_hwdb *hwdb = NULL;
 677                 int r;
 678
 679                 r = sd_hwdb_new(&hwdb);
 680                 if (r >= 0) {
 681                         const char *key, *value;
 682
 683                         SD_HWDB_FOREACH_PROPERTY(hwdb, test, key, value)
 684                                 printf("%s=%s\n", key, value);
 685                 }
 686         }
 687 out:
 688         if (trie) {
 689                 if (trie->root)
 690                         trie_node_cleanup(trie->root);
 691                 strbuf_cleanup(trie->strings);
 692                 free(trie);
 693         }
 694         return rc;
 695 }
 696
 697 const struct udevadm_cmd udevadm_hwdb = {
 698         .name = "hwdb",
 699         .cmd = adm_hwdb,
 700 };