2 This file is part of systemd.
4 Copyright 2012 Kay Sievers <kay@vrfy.org>
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.
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.
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/>.
28 #include "conf-files.h"
31 #include "libudev-hwdb-def.h"
34 * Generic udev properties, key/value database based on modalias strings.
35 * Uses a Patricia/radix trie to index all matches for efficient lookup.
38 static const char * const conf_file_dirs[] = {
40 UDEVLIBEXECDIR "/hwdb.d",
44 /* in-memory trie objects */
46 struct trie_node *root;
47 struct strbuf *strings;
50 size_t children_count;
55 /* prefix, common part for all children of this node */
58 /* sorted array of pointers to children nodes */
59 struct trie_child_entry *children;
60 uint8_t children_count;
62 /* sorted array of key/value pairs */
63 struct trie_value_entry *values;
67 /* children array item with char (0-255) index */
68 struct trie_child_entry {
70 struct trie_node *child;
73 /* value array item with key/value pairs */
74 struct trie_value_entry {
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;
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;
89 /* extend array, add new entry, sort for bisection */
90 child = realloc(node->children, (node->children_count + 1) * sizeof(struct trie_child_entry));
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);
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;
110 child = bsearch(&search, node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
116 static void trie_node_cleanup(struct trie_node *node) {
119 for (i = 0; i < node->children_count; i++)
120 trie_node_cleanup(node->children[i].child);
121 free(node->children);
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;
131 return strcmp(trie->strings->buf + val1->key_off,
132 trie->strings->buf + val2->key_off);
135 static int trie_node_add_value(struct trie *trie, struct trie_node *node,
136 const char *key, const char *value) {
138 struct trie_value_entry *val;
140 k = strbuf_add_string(trie->strings, key, strlen(key));
143 v = strbuf_add_string(trie->strings, value, strlen(value));
147 if (node->values_count) {
148 struct trie_value_entry search = {
153 val = xbsearch_r(&search, node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
155 /* replace existing earlier key with new value */
161 /* extend array, add new entry, sort for bisection */
162 val = realloc(node->values, (node->values_count + 1) * sizeof(struct trie_value_entry));
165 trie->values_count++;
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);
174 static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,
175 const char *key, const char *value) {
182 struct trie_node *child;
184 for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {
185 _cleanup_free_ char *s = NULL;
187 _cleanup_free_ struct trie_node *new_child = NULL;
189 if (c == search[i + p])
193 new_child = new0(struct trie_node, 1);
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;
204 /* update parent; use strdup() because the source gets realloc()d */
205 s = strndup(trie->strings->buf + node->prefix_off, p);
209 off = strbuf_add_string(trie->strings, s, p);
213 node->prefix_off = off;
214 node->children = NULL;
215 node->children_count = 0;
217 node->values_count = 0;
218 err = node_add_child(trie, node, new_child, c);
222 new_child = NULL; /* avoid cleanup */
229 return trie_node_add_value(trie, node, key, value);
231 child = node_lookup(node, c);
236 child = new0(struct trie_node, 1);
240 off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));
246 child->prefix_off = off;
247 err = node_add_child(trie, node, child, c);
253 return trie_node_add_value(trie, child, key, value);
264 uint64_t strings_off;
266 uint64_t nodes_count;
267 uint64_t children_count;
268 uint64_t values_count;
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) {
275 for (i = 0; i < node->children_count; i++)
276 trie_store_nodes_size(trie, node->children[i].child);
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);
285 static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node) {
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),
292 struct trie_child_entry_f *children = NULL;
295 if (node->children_count) {
296 children = new0(struct trie_child_entry_f, node->children_count);
301 /* post-order recursion */
302 for (i = 0; i < node->children_count; i++) {
305 child_off = trie_store_nodes(trie, node->children[i].child);
310 children[i].c = node->children[i].c;
311 children[i].child_off = htole64(child_off);
315 node_off = ftello(trie->f);
316 fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);
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;
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),
333 fwrite(&v, sizeof(struct trie_value_entry_f), 1, trie->f);
334 trie->values_count++;
340 static int trie_store(struct trie *trie, const char *filename) {
344 _cleanup_free_ char *filename_tmp = NULL;
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)),
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);
362 err = fopen_temporary(filename , &t.f, &filename_tmp);
365 fchmod(fileno(t.f), 0444);
368 err = fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET);
371 unlink_noerrno(filename_tmp);
374 root_off = trie_store_nodes(&t, trie->root);
375 h.nodes_root_off = htole64(root_off);
377 h.nodes_len = htole64(pos - sizeof(struct trie_header_f));
379 /* write string buffer */
380 fwrite(trie->strings->buf, trie->strings->len, 1, t.f);
381 h.strings_len = htole64(trie->strings->len);
385 h.file_size = htole64(size);
386 err = fseeko(t.f, 0, SEEK_SET);
389 unlink_noerrno(filename_tmp);
392 fwrite(&h, sizeof(struct trie_header_f), 1, t.f);
397 if (err < 0 || rename(filename_tmp, filename) < 0) {
398 unlink_noerrno(filename_tmp);
399 return err < 0 ? err : -errno;
402 log_debug("=== trie on-disk ===");
403 log_debug("size: %8"PRIu64" bytes", size);
404 log_debug("header: %8zu bytes", sizeof(struct trie_header_f));
405 log_debug("nodes: %8"PRIu64" bytes (%8"PRIu64")",
406 t.nodes_count * sizeof(struct trie_node_f), t.nodes_count);
407 log_debug("child pointers: %8"PRIu64" bytes (%8"PRIu64")",
408 t.children_count * sizeof(struct trie_child_entry_f), t.children_count);
409 log_debug("value pointers: %8"PRIu64" bytes (%8"PRIu64")",
410 t.values_count * sizeof(struct trie_value_entry_f), t.values_count);
411 log_debug("string store: %8zu bytes", trie->strings->len);
412 log_debug("strings start: %8"PRIu64, t.strings_off);
417 static int insert_data(struct trie *trie, struct udev_list *match_list,
418 char *line, const char *filename) {
420 struct udev_list_entry *entry;
422 value = strchr(line, '=');
424 log_error("Error, key/value pair expected but got '%s' in '%s':", line, filename);
431 if (line[0] == '\0' || value[0] == '\0') {
432 log_error("Error, empty key or value '%s' in '%s':", line, filename);
436 udev_list_entry_foreach(entry, udev_list_get_entry(match_list))
437 trie_insert(trie, trie->root, udev_list_entry_get_name(entry), line, value);
442 static int import_file(struct udev *udev, struct trie *trie, const char *filename) {
450 struct udev_list match_list;
452 udev_list_init(udev, &match_list, false);
454 f = fopen(filename, "re");
458 while (fgets(line, sizeof(line), f)) {
466 /* strip trailing comment */
467 pos = strchr(line, '#');
471 /* strip trailing whitespace */
473 while (len > 0 && isspace(line[len-1]))
482 if (line[0] == ' ') {
483 log_error("Error, MATCH expected but got '%s' in '%s':", line, filename);
487 /* start of record, first match */
489 udev_list_entry_add(&match_list, line, NULL);
494 log_error("Error, DATA expected but got empty line in '%s':", filename);
496 udev_list_cleanup(&match_list);
501 if (line[0] != ' ') {
502 udev_list_entry_add(&match_list, line, NULL);
508 insert_data(trie, &match_list, line, filename);
515 udev_list_cleanup(&match_list);
519 if (line[0] != ' ') {
520 log_error("Error, DATA expected but got '%s' in '%s':", line, filename);
522 udev_list_cleanup(&match_list);
526 insert_data(trie, &match_list, line, filename);
532 udev_list_cleanup(&match_list);
536 static void help(void) {
537 printf("Usage: udevadm hwdb OPTIONS\n"
538 " -u,--update update the hardware database\n"
539 " -t,--test=MODALIAS query database and print result\n"
540 " -r,--root=PATH alternative root path in the filesystem\n"
544 static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {
545 static const struct option options[] = {
546 { "update", no_argument, NULL, 'u' },
547 { "test", required_argument, NULL, 't' },
548 { "root", required_argument, NULL, 'r' },
549 { "help", no_argument, NULL, 'h' },
552 const char *test = NULL;
553 const char *root = "";
555 struct trie *trie = NULL;
557 int rc = EXIT_SUCCESS;
559 while ((c = getopt_long(argc, argv, "ut:r:h", options, NULL)) >= 0)
576 assert_not_reached("Unknown option");
579 if (!update && !test) {
580 log_error("Either --update or --test must be used");
586 _cleanup_free_ char *hwdb_bin = NULL;
588 trie = new0(struct trie, 1);
595 trie->strings = strbuf_new();
596 if (!trie->strings) {
602 trie->root = new0(struct trie_node, 1);
609 err = conf_files_list_strv(&files, ".hwdb", root, conf_file_dirs);
611 log_error("failed to enumerate hwdb files: %s", strerror(-err));
615 STRV_FOREACH(f, files) {
616 log_debug("reading file '%s'", *f);
617 import_file(udev, trie, *f);
621 strbuf_complete(trie->strings);
623 log_debug("=== trie in-memory ===");
624 log_debug("nodes: %8zu bytes (%8zu)",
625 trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);
626 log_debug("children arrays: %8zu bytes (%8zu)",
627 trie->children_count * sizeof(struct trie_child_entry), trie->children_count);
628 log_debug("values arrays: %8zu bytes (%8zu)",
629 trie->values_count * sizeof(struct trie_value_entry), trie->values_count);
630 log_debug("strings: %8zu bytes",
632 log_debug("strings incoming: %8zu bytes (%8zu)",
633 trie->strings->in_len, trie->strings->in_count);
634 log_debug("strings dedup'ed: %8zu bytes (%8zu)",
635 trie->strings->dedup_len, trie->strings->dedup_count);
637 if (asprintf(&hwdb_bin, "%s/etc/udev/hwdb.bin", root) < 0) {
641 mkdir_parents(hwdb_bin, 0755);
642 err = trie_store(trie, hwdb_bin);
644 log_error("Failure writing database %s: %s", hwdb_bin, strerror(-err));
650 struct udev_hwdb *hwdb = udev_hwdb_new(udev);
653 struct udev_list_entry *entry;
655 udev_list_entry_foreach(entry, udev_hwdb_get_properties_list_entry(hwdb, test, 0))
656 printf("%s=%s\n", udev_list_entry_get_name(entry), udev_list_entry_get_value(entry));
657 udev_hwdb_unref(hwdb);
663 trie_node_cleanup(trie->root);
664 strbuf_cleanup(trie->strings);
670 const struct udevadm_cmd udevadm_hwdb = {
673 .help = "maintain the hardware database index",