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/>.
27 #include "conf-files.h"
30 #include "libudev-hwdb-def.h"
33 * Generic udev properties, key/value database based on modalias strings.
34 * Uses a Patricia/radix trie to index all matches for efficient lookup.
37 static const char * const conf_file_dirs[] = {
39 UDEVLIBEXECDIR "/hwdb.d",
43 /* in-memory trie objects */
45 struct trie_node *root;
46 struct strbuf *strings;
49 size_t children_count;
54 /* prefix, common part for all children of this node */
57 /* sorted array of pointers to children nodes */
58 struct trie_child_entry *children;
59 uint8_t children_count;
61 /* sorted array of key/value pairs */
62 struct trie_value_entry *values;
66 /* children array item with char (0-255) index */
67 struct trie_child_entry {
69 struct trie_node *child;
72 /* value array item with key/value pairs */
73 struct trie_value_entry {
78 static int trie_children_cmp(const void *v1, const void *v2) {
79 const struct trie_child_entry *n1 = v1;
80 const struct trie_child_entry *n2 = v2;
85 static int node_add_child(struct trie *trie, struct trie_node *node, struct trie_node *node_child, uint8_t c) {
86 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));
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);
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;
111 child = bsearch(&search, node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);
117 static void trie_node_cleanup(struct trie_node *node) {
120 for (i = 0; i < node->children_count; i++)
121 trie_node_cleanup(node->children[i].child);
122 free(node->children);
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;
132 return strcmp(trie->strings->buf + val1->key_off,
133 trie->strings->buf + val2->key_off);
136 static int trie_node_add_value(struct trie *trie, struct trie_node *node,
137 const char *key, const char *value) {
139 struct trie_value_entry *val;
141 k = strbuf_add_string(trie->strings, key, strlen(key));
144 v = strbuf_add_string(trie->strings, value, strlen(value));
148 if (node->values_count) {
149 struct trie_value_entry search = {
154 val = xbsearch_r(&search, node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);
156 /* replace existing earlier key with new value */
162 /* extend array, add new entry, sort for bisection */
163 val = realloc(node->values, (node->values_count + 1) * sizeof(struct trie_value_entry));
166 trie->values_count++;
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);
175 static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,
176 const char *key, const char *value) {
179 struct trie_node _cleanup_free_ *child = NULL;
185 for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {
189 if (c == search[i + p])
193 child = calloc(sizeof(struct trie_node), 1);
199 /* move values from parent to child */
200 child->prefix_off = node->prefix_off + p+1;
201 child->children = node->children;
202 child->children_count = node->children_count;
203 child->values = node->values;
204 child->values_count = node->values_count;
206 /* update parent; use strdup() because the source gets realloc()d */
207 s = strndup(trie->strings->buf + node->prefix_off, p);
212 off = strbuf_add_string(trie->strings, s, p);
218 node->prefix_off = off;
219 node->children = NULL;
220 node->children_count = 0;
222 node->values_count = 0;
223 err = node_add_child(trie, node, child, c);
232 return trie_node_add_value(trie, node, key, value);
234 child = node_lookup(node, c);
239 child = calloc(sizeof(struct trie_node), 1);
244 off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));
249 child->prefix_off = off;
250 err = node_add_child(trie, node, child, c);
253 return trie_node_add_value(trie, child, key, value);
257 child = NULL; /* avoid cleanup */
267 uint64_t strings_off;
269 uint64_t nodes_count;
270 uint64_t children_count;
271 uint64_t values_count;
274 /* calculate the storage space for the nodes, children arrays, value arrays */
275 static void trie_store_nodes_size(struct trie_f *trie, struct trie_node *node) {
278 for (i = 0; i < node->children_count; i++)
279 trie_store_nodes_size(trie, node->children[i].child);
281 trie->strings_off += sizeof(struct trie_node_f);
282 for (i = 0; i < node->children_count; i++)
283 trie->strings_off += sizeof(struct trie_child_entry_f);
284 for (i = 0; i < node->values_count; i++)
285 trie->strings_off += sizeof(struct trie_value_entry_f);
288 static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node) {
290 struct trie_node_f n = {
291 .prefix_off = htole64(trie->strings_off + node->prefix_off),
292 .children_count = node->children_count,
293 .values_count = htole64(node->values_count),
295 struct trie_child_entry_f *children = NULL;
298 if (node->children_count) {
299 children = new0(struct trie_child_entry_f, node->children_count);
304 /* post-order recursion */
305 for (i = 0; i < node->children_count; i++) {
308 child_off = trie_store_nodes(trie, node->children[i].child);
311 children[i].c = node->children[i].c;
312 children[i].child_off = htole64(child_off);
316 node_off = ftello(trie->f);
317 fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);
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;
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),
334 fwrite(&v, sizeof(struct trie_value_entry_f), 1, trie->f);
335 trie->values_count++;
341 static int trie_store(struct trie *trie, const char *filename) {
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)),
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);
363 err = fopen_temporary(filename , &t.f, &filename_tmp);
366 fchmod(fileno(t.f), 0444);
369 fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET);
370 root_off = trie_store_nodes(&t, trie->root);
371 h.nodes_root_off = htole64(root_off);
373 h.nodes_len = htole64(pos - sizeof(struct trie_header_f));
375 /* write string buffer */
376 fwrite(trie->strings->buf, trie->strings->len, 1, t.f);
377 h.strings_len = htole64(trie->strings->len);
381 h.file_size = htole64(size);
382 fseeko(t.f, 0, SEEK_SET);
383 fwrite(&h, sizeof(struct trie_header_f), 1, t.f);
388 if (err < 0 || rename(filename_tmp, filename) < 0) {
389 unlink(filename_tmp);
393 log_debug("=== trie on-disk ===\n");
394 log_debug("size: %8llu bytes\n", (unsigned long long)size);
395 log_debug("header: %8zu bytes\n", sizeof(struct trie_header_f));
396 log_debug("nodes: %8llu bytes (%8llu)\n",
397 (unsigned long long)t.nodes_count * sizeof(struct trie_node_f), (unsigned long long)t.nodes_count);
398 log_debug("child pointers: %8llu bytes (%8llu)\n",
399 (unsigned long long)t.children_count * sizeof(struct trie_child_entry_f), (unsigned long long)t.children_count);
400 log_debug("value pointers: %8llu bytes (%8llu)\n",
401 (unsigned long long)t.values_count * sizeof(struct trie_value_entry_f), (unsigned long long)t.values_count);
402 log_debug("string store: %8llu bytes\n", (unsigned long long)trie->strings->len);
403 log_debug("strings start: %8llu\n", (unsigned long long) t.strings_off);
409 static int import_file(struct trie *trie, const char *filename) {
412 char match[LINE_MAX];
415 f = fopen(filename, "re");
421 while (fgets(line, sizeof(line), f)) {
427 /* new line, new record */
428 if (line[0] == '\n') {
440 /* start of new record */
441 if (match[0] == '\0') {
447 if (line[0] == '+') {
452 /* TODO: support +; skip the entire record until we support it */
457 if (line[0] == ' ') {
460 value = strchr(line, '=');
465 trie_insert(trie, trie->root, match, line, value);
472 static void help(void) {
473 printf("Usage: udevadm hwdb OPTIONS\n"
474 " --update update the hardware database\n"
475 " --test=<modalias> query database and print result\n"
476 " --root=<path> alternative root path in the filesystem\n"
480 static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {
481 static const struct option options[] = {
482 { "update", no_argument, NULL, 'u' },
483 { "root", required_argument, NULL, 'r' },
484 { "test", required_argument, NULL, 't' },
485 { "help", no_argument, NULL, 'h' },
488 const char *test = NULL;
489 const char *root = "";
491 struct trie *trie = NULL;
493 int rc = EXIT_SUCCESS;
498 option = getopt_long(argc, argv, "ut:r:h", options, NULL);
518 if (!update && !test) {
525 _cleanup_free_ char *hwdb_bin = NULL;
527 trie = calloc(sizeof(struct trie), 1);
534 trie->strings = strbuf_new();
535 if (!trie->strings) {
541 trie->root = calloc(sizeof(struct trie_node), 1);
548 err = conf_files_list_strv(&files, ".hwdb", root, conf_file_dirs);
550 log_error("failed to enumerate hwdb files: %s\n", strerror(-err));
554 STRV_FOREACH(f, files) {
555 log_debug("reading file '%s'", *f);
556 import_file(trie, *f);
560 strbuf_complete(trie->strings);
562 log_debug("=== trie in-memory ===\n");
563 log_debug("nodes: %8zu bytes (%8zu)\n",
564 trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);
565 log_debug("children arrays: %8zu bytes (%8zu)\n",
566 trie->children_count * sizeof(struct trie_child_entry), trie->children_count);
567 log_debug("values arrays: %8zu bytes (%8zu)\n",
568 trie->values_count * sizeof(struct trie_value_entry), trie->values_count);
569 log_debug("strings: %8zu bytes\n",
571 log_debug("strings incoming: %8zu bytes (%8zu)\n",
572 trie->strings->in_len, trie->strings->in_count);
573 log_debug("strings dedup'ed: %8zu bytes (%8zu)\n",
574 trie->strings->dedup_len, trie->strings->dedup_count);
576 if (asprintf(&hwdb_bin, "%s/etc/udev/hwdb.bin", root) < 0) {
580 mkdir_parents(hwdb_bin, 0755);
581 err = trie_store(trie, hwdb_bin);
583 log_error("Failure writing database %s: %s", hwdb_bin, strerror(-err));
589 struct udev_hwdb *hwdb = udev_hwdb_new(udev);
592 struct udev_list_entry *entry;
594 udev_list_entry_foreach(entry, udev_hwdb_get_properties_list_entry(hwdb, test, 0))
595 printf("%s=%s\n", udev_list_entry_get_name(entry), udev_list_entry_get_value(entry));
596 hwdb = udev_hwdb_unref(hwdb);
602 trie_node_cleanup(trie->root);
603 strbuf_cleanup(trie->strings);
609 const struct udevadm_cmd udevadm_hwdb = {
612 .help = "maintain the hardware database index",