| /*** |
| This file is part of systemd. |
| |
| Copyright 2012 Kay Sievers <kay@vrfy.org> |
| Copyright 2008 Alan Jenkins <alan.christopher.jenkins@googlemail.com> |
| Copyright 2014 Tom Gundersen <teg@jklm.no> |
| |
| systemd is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 of the License, or |
| (at your option) any later version. |
| |
| systemd is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public License |
| along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| ***/ |
| |
| #include <stdio.h> |
| #include <errno.h> |
| #include <string.h> |
| #include <inttypes.h> |
| #include <stdlib.h> |
| #include <fnmatch.h> |
| #include <sys/mman.h> |
| |
| #include "sd-hwdb.h" |
| |
| #include "hashmap.h" |
| #include "refcnt.h" |
| |
| #include "hwdb-util.h" |
| #include "hwdb-internal.h" |
| |
| struct sd_hwdb { |
| RefCount n_ref; |
| int refcount; |
| |
| FILE *f; |
| struct stat st; |
| union { |
| struct trie_header_f *head; |
| const char *map; |
| }; |
| |
| char *modalias; |
| |
| OrderedHashmap *properties; |
| Iterator properties_iterator; |
| bool properties_modified; |
| }; |
| |
| struct linebuf { |
| char bytes[LINE_MAX]; |
| size_t size; |
| size_t len; |
| }; |
| |
| static void linebuf_init(struct linebuf *buf) { |
| buf->size = 0; |
| buf->len = 0; |
| } |
| |
| static const char *linebuf_get(struct linebuf *buf) { |
| if (buf->len + 1 >= sizeof(buf->bytes)) |
| return NULL; |
| buf->bytes[buf->len] = '\0'; |
| return buf->bytes; |
| } |
| |
| static bool linebuf_add(struct linebuf *buf, const char *s, size_t len) { |
| if (buf->len + len >= sizeof(buf->bytes)) |
| return false; |
| memcpy(buf->bytes + buf->len, s, len); |
| buf->len += len; |
| return true; |
| } |
| |
| static bool linebuf_add_char(struct linebuf *buf, char c) { |
| if (buf->len + 1 >= sizeof(buf->bytes)) |
| return false; |
| buf->bytes[buf->len++] = c; |
| return true; |
| } |
| |
| static void linebuf_rem(struct linebuf *buf, size_t count) { |
| assert(buf->len >= count); |
| buf->len -= count; |
| } |
| |
| static void linebuf_rem_char(struct linebuf *buf) { |
| linebuf_rem(buf, 1); |
| } |
| |
| static const struct trie_child_entry_f *trie_node_children(sd_hwdb *hwdb, const struct trie_node_f *node) { |
| return (const struct trie_child_entry_f *)((const char *)node + le64toh(hwdb->head->node_size)); |
| } |
| |
| static const struct trie_value_entry_f *trie_node_values(sd_hwdb *hwdb, const struct trie_node_f *node) { |
| const char *base = (const char *)node; |
| |
| base += le64toh(hwdb->head->node_size); |
| base += node->children_count * le64toh(hwdb->head->child_entry_size); |
| return (const struct trie_value_entry_f *)base; |
| } |
| |
| static const struct trie_node_f *trie_node_from_off(sd_hwdb *hwdb, le64_t off) { |
| return (const struct trie_node_f *)(hwdb->map + le64toh(off)); |
| } |
| |
| static const char *trie_string(sd_hwdb *hwdb, le64_t off) { |
| return hwdb->map + le64toh(off); |
| } |
| |
| static int trie_children_cmp_f(const void *v1, const void *v2) { |
| const struct trie_child_entry_f *n1 = v1; |
| const struct trie_child_entry_f *n2 = v2; |
| |
| return n1->c - n2->c; |
| } |
| |
| static const struct trie_node_f *node_lookup_f(sd_hwdb *hwdb, const struct trie_node_f *node, uint8_t c) { |
| struct trie_child_entry_f *child; |
| struct trie_child_entry_f search; |
| |
| search.c = c; |
| child = bsearch(&search, trie_node_children(hwdb, node), node->children_count, |
| le64toh(hwdb->head->child_entry_size), trie_children_cmp_f); |
| if (child) |
| return trie_node_from_off(hwdb, child->child_off); |
| return NULL; |
| } |
| |
| static int hwdb_add_property(sd_hwdb *hwdb, const char *key, const char *value) { |
| int r; |
| |
| assert(hwdb); |
| assert(key); |
| assert(value); |
| |
| /* |
| * Silently ignore all properties which do not start with a |
| * space; future extensions might use additional prefixes. |
| */ |
| if (key[0] != ' ') |
| return 0; |
| |
| key++; |
| |
| r = ordered_hashmap_ensure_allocated(&hwdb->properties, &string_hash_ops); |
| if (r < 0) |
| return r; |
| |
| r = ordered_hashmap_replace(hwdb->properties, key, (char*)value); |
| if (r < 0) |
| return r; |
| |
| hwdb->properties_modified = true; |
| |
| return 0; |
| } |
| |
| static int trie_fnmatch_f(sd_hwdb *hwdb, const struct trie_node_f *node, size_t p, |
| struct linebuf *buf, const char *search) { |
| size_t len; |
| size_t i; |
| const char *prefix; |
| int err; |
| |
| prefix = trie_string(hwdb, node->prefix_off); |
| len = strlen(prefix + p); |
| linebuf_add(buf, prefix + p, len); |
| |
| for (i = 0; i < node->children_count; i++) { |
| const struct trie_child_entry_f *child = &trie_node_children(hwdb, node)[i]; |
| |
| linebuf_add_char(buf, child->c); |
| err = trie_fnmatch_f(hwdb, trie_node_from_off(hwdb, child->child_off), 0, buf, search); |
| if (err < 0) |
| return err; |
| linebuf_rem_char(buf); |
| } |
| |
| if (le64toh(node->values_count) && fnmatch(linebuf_get(buf), search, 0) == 0) |
| for (i = 0; i < le64toh(node->values_count); i++) { |
| err = hwdb_add_property(hwdb, trie_string(hwdb, trie_node_values(hwdb, node)[i].key_off), |
| trie_string(hwdb, trie_node_values(hwdb, node)[i].value_off)); |
| if (err < 0) |
| return err; |
| } |
| |
| linebuf_rem(buf, len); |
| return 0; |
| } |
| |
| static int trie_search_f(sd_hwdb *hwdb, const char *search) { |
| struct linebuf buf; |
| const struct trie_node_f *node; |
| size_t i = 0; |
| int err; |
| |
| linebuf_init(&buf); |
| |
| node = trie_node_from_off(hwdb, hwdb->head->nodes_root_off); |
| while (node) { |
| const struct trie_node_f *child; |
| size_t p = 0; |
| |
| if (node->prefix_off) { |
| uint8_t c; |
| |
| for (; (c = trie_string(hwdb, node->prefix_off)[p]); p++) { |
| if (c == '*' || c == '?' || c == '[') |
| return trie_fnmatch_f(hwdb, node, p, &buf, search + i + p); |
| if (c != search[i + p]) |
| return 0; |
| } |
| i += p; |
| } |
| |
| child = node_lookup_f(hwdb, node, '*'); |
| if (child) { |
| linebuf_add_char(&buf, '*'); |
| err = trie_fnmatch_f(hwdb, child, 0, &buf, search + i); |
| if (err < 0) |
| return err; |
| linebuf_rem_char(&buf); |
| } |
| |
| child = node_lookup_f(hwdb, node, '?'); |
| if (child) { |
| linebuf_add_char(&buf, '?'); |
| err = trie_fnmatch_f(hwdb, child, 0, &buf, search + i); |
| if (err < 0) |
| return err; |
| linebuf_rem_char(&buf); |
| } |
| |
| child = node_lookup_f(hwdb, node, '['); |
| if (child) { |
| linebuf_add_char(&buf, '['); |
| err = trie_fnmatch_f(hwdb, child, 0, &buf, search + i); |
| if (err < 0) |
| return err; |
| linebuf_rem_char(&buf); |
| } |
| |
| if (search[i] == '\0') { |
| size_t n; |
| |
| for (n = 0; n < le64toh(node->values_count); n++) { |
| err = hwdb_add_property(hwdb, trie_string(hwdb, trie_node_values(hwdb, node)[n].key_off), |
| trie_string(hwdb, trie_node_values(hwdb, node)[n].value_off)); |
| if (err < 0) |
| return err; |
| } |
| return 0; |
| } |
| |
| child = node_lookup_f(hwdb, node, search[i]); |
| node = child; |
| i++; |
| } |
| return 0; |
| } |
| |
| static const char hwdb_bin_paths[] = |
| "/etc/systemd/hwdb/hwdb.bin\0" |
| "/etc/udev/hwdb.bin\0" |
| "/usr/lib/systemd/hwdb/hwdb.bin\0" |
| #ifdef HAVE_SPLIT_USR |
| "/lib/systemd/hwdb/hwdb.bin\0" |
| #endif |
| UDEVLIBEXECDIR "/hwdb.bin\0"; |
| |
| _public_ int sd_hwdb_new(sd_hwdb **ret) { |
| _cleanup_hwdb_unref_ sd_hwdb *hwdb = NULL; |
| const char *hwdb_bin_path; |
| const char sig[] = HWDB_SIG; |
| |
| assert_return(ret, -EINVAL); |
| |
| hwdb = new0(sd_hwdb, 1); |
| if (!hwdb) |
| return -ENOMEM; |
| |
| hwdb->n_ref = REFCNT_INIT; |
| |
| /* find hwdb.bin in hwdb_bin_paths */ |
| NULSTR_FOREACH(hwdb_bin_path, hwdb_bin_paths) { |
| hwdb->f = fopen(hwdb_bin_path, "re"); |
| if (hwdb->f) |
| break; |
| else if (errno == ENOENT) |
| continue; |
| else |
| return log_debug_errno(errno, "error reading %s: %m", hwdb_bin_path); |
| } |
| |
| if (!hwdb->f) { |
| log_debug("hwdb.bin does not exist, please run udevadm hwdb --update"); |
| return -ENOENT; |
| } |
| |
| if (fstat(fileno(hwdb->f), &hwdb->st) < 0 || |
| (size_t)hwdb->st.st_size < offsetof(struct trie_header_f, strings_len) + 8) |
| return log_debug_errno(errno, "error reading %s: %m", hwdb_bin_path); |
| |
| hwdb->map = mmap(0, hwdb->st.st_size, PROT_READ, MAP_SHARED, fileno(hwdb->f), 0); |
| if (hwdb->map == MAP_FAILED) |
| return log_debug_errno(errno, "error mapping %s: %m", hwdb_bin_path); |
| |
| if (memcmp(hwdb->map, sig, sizeof(hwdb->head->signature)) != 0 || |
| (size_t)hwdb->st.st_size != le64toh(hwdb->head->file_size)) { |
| log_debug("error recognizing the format of %s", hwdb_bin_path); |
| return -EINVAL; |
| } |
| |
| log_debug("=== trie on-disk ==="); |
| log_debug("tool version: %"PRIu64, le64toh(hwdb->head->tool_version)); |
| log_debug("file size: %8"PRIi64" bytes", hwdb->st.st_size); |
| log_debug("header size %8"PRIu64" bytes", le64toh(hwdb->head->header_size)); |
| log_debug("strings %8"PRIu64" bytes", le64toh(hwdb->head->strings_len)); |
| log_debug("nodes %8"PRIu64" bytes", le64toh(hwdb->head->nodes_len)); |
| |
| *ret = hwdb; |
| hwdb = NULL; |
| |
| return 0; |
| } |
| |
| _public_ sd_hwdb *sd_hwdb_ref(sd_hwdb *hwdb) { |
| assert_return(hwdb, NULL); |
| |
| assert_se(REFCNT_INC(hwdb->n_ref) >= 2); |
| |
| return hwdb; |
| } |
| |
| _public_ sd_hwdb *sd_hwdb_unref(sd_hwdb *hwdb) { |
| if (hwdb && REFCNT_DEC(hwdb->n_ref) == 0) { |
| if (hwdb->map) |
| munmap((void *)hwdb->map, hwdb->st.st_size); |
| safe_fclose(hwdb->f); |
| free(hwdb->modalias); |
| ordered_hashmap_free(hwdb->properties); |
| free(hwdb); |
| } |
| |
| return NULL; |
| } |
| |
| bool hwdb_validate(sd_hwdb *hwdb) { |
| bool found = false; |
| const char* p; |
| struct stat st; |
| |
| if (!hwdb) |
| return false; |
| if (!hwdb->f) |
| return false; |
| |
| /* if hwdb.bin doesn't exist anywhere, we need to update */ |
| NULSTR_FOREACH(p, hwdb_bin_paths) { |
| if (stat(p, &st) >= 0) { |
| found = true; |
| break; |
| } |
| } |
| if (!found) |
| return true; |
| |
| if (timespec_load(&hwdb->st.st_mtim) != timespec_load(&st.st_mtim)) |
| return true; |
| return false; |
| } |
| |
| static int properties_prepare(sd_hwdb *hwdb, const char *modalias) { |
| _cleanup_free_ char *mod = NULL; |
| int r; |
| |
| assert(hwdb); |
| assert(modalias); |
| |
| if (streq_ptr(modalias, hwdb->modalias)) |
| return 0; |
| |
| mod = strdup(modalias); |
| if (!mod) |
| return -ENOMEM; |
| |
| ordered_hashmap_clear(hwdb->properties); |
| |
| hwdb->properties_modified = true; |
| |
| r = trie_search_f(hwdb, modalias); |
| if (r < 0) |
| return r; |
| |
| free(hwdb->modalias); |
| hwdb->modalias = mod; |
| mod = NULL; |
| |
| return 0; |
| } |
| |
| _public_ int sd_hwdb_get(sd_hwdb *hwdb, const char *modalias, const char *key, const char **_value) { |
| const char *value; |
| int r; |
| |
| assert_return(hwdb, -EINVAL); |
| assert_return(hwdb->f, -EINVAL); |
| assert_return(modalias, -EINVAL); |
| assert_return(_value, -EINVAL); |
| |
| r = properties_prepare(hwdb, modalias); |
| if (r < 0) |
| return r; |
| |
| value = ordered_hashmap_get(hwdb->properties, key); |
| if (!value) |
| return -ENOENT; |
| |
| *_value = value; |
| |
| return 0; |
| } |
| |
| _public_ int sd_hwdb_seek(sd_hwdb *hwdb, const char *modalias) { |
| int r; |
| |
| assert_return(hwdb, -EINVAL); |
| assert_return(hwdb->f, -EINVAL); |
| assert_return(modalias, -EINVAL); |
| |
| r = properties_prepare(hwdb, modalias); |
| if (r < 0) |
| return r; |
| |
| hwdb->properties_modified = false; |
| hwdb->properties_iterator = ITERATOR_FIRST; |
| |
| return 0; |
| } |
| |
| _public_ int sd_hwdb_enumerate(sd_hwdb *hwdb, const char **key, const char **value) { |
| const void *k; |
| void *v; |
| |
| assert_return(hwdb, -EINVAL); |
| assert_return(key, -EINVAL); |
| assert_return(value, -EINVAL); |
| |
| if (hwdb->properties_modified) |
| return -EAGAIN; |
| |
| ordered_hashmap_iterate(hwdb->properties, &hwdb->properties_iterator, &v, &k); |
| if (!k) |
| return 0; |
| |
| *key = k; |
| *value = v; |
| |
| return 1; |
| } |