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-rw-r--r--src/libsystemd/sd-hwdb/hwdb-internal.h89
-rw-r--r--src/libsystemd/sd-hwdb/sd-hwdb.c436
2 files changed, 525 insertions, 0 deletions
diff --git a/src/libsystemd/sd-hwdb/hwdb-internal.h b/src/libsystemd/sd-hwdb/hwdb-internal.h
new file mode 100644
index 0000000..9db3b31
--- /dev/null
+++ b/src/libsystemd/sd-hwdb/hwdb-internal.h
@@ -0,0 +1,89 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <stdint.h>
+#include <sys/stat.h>
+
+#include "constants.h"
+#include "hashmap.h"
+#include "sparse-endian.h"
+
+#define HWDB_SIG { 'K', 'S', 'L', 'P', 'H', 'H', 'R', 'H' }
+
+struct sd_hwdb {
+ unsigned n_ref;
+
+ FILE *f;
+ struct stat st;
+ union {
+ struct trie_header_f *head;
+ const char *map;
+ };
+
+ OrderedHashmap *properties;
+ Iterator properties_iterator;
+ bool properties_modified;
+};
+
+/* on-disk trie objects */
+struct trie_header_f {
+ uint8_t signature[8];
+
+ /* version of tool which created the file */
+ le64_t tool_version;
+ le64_t file_size;
+
+ /* size of structures to allow them to grow */
+ le64_t header_size;
+ le64_t node_size;
+ le64_t child_entry_size;
+ le64_t value_entry_size;
+
+ /* offset of the root trie node */
+ le64_t nodes_root_off;
+
+ /* size of the nodes and string section */
+ le64_t nodes_len;
+ le64_t strings_len;
+} _packed_;
+
+struct trie_node_f {
+ /* prefix of lookup string, shared by all children */
+ le64_t prefix_off;
+ /* size of children entry array appended to the node */
+ uint8_t children_count;
+ uint8_t padding[7];
+ /* size of value entry array appended to the node */
+ le64_t values_count;
+} _packed_;
+
+/* array of child entries, follows directly the node record */
+struct trie_child_entry_f {
+ /* index of the child node */
+ uint8_t c;
+ uint8_t padding[7];
+ /* offset of the child node */
+ le64_t child_off;
+} _packed_;
+
+/* array of value entries, follows directly the node record/child array */
+struct trie_value_entry_f {
+ le64_t key_off;
+ le64_t value_off;
+} _packed_;
+
+/* v2 extends v1 with filename and line-number */
+struct trie_value_entry2_f {
+ le64_t key_off;
+ le64_t value_off;
+ le64_t filename_off;
+ le32_t line_number;
+ le16_t file_priority;
+ le16_t padding;
+} _packed_;
+
+#define hwdb_bin_paths \
+ "/etc/systemd/hwdb/hwdb.bin\0" \
+ "/etc/udev/hwdb.bin\0" \
+ "/usr/lib/systemd/hwdb/hwdb.bin\0" \
+ UDEVLIBEXECDIR "/hwdb.bin\0"
diff --git a/src/libsystemd/sd-hwdb/sd-hwdb.c b/src/libsystemd/sd-hwdb/sd-hwdb.c
new file mode 100644
index 0000000..f163314
--- /dev/null
+++ b/src/libsystemd/sd-hwdb/sd-hwdb.c
@@ -0,0 +1,436 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/***
+ Copyright © 2008 Alan Jenkins <alan.christopher.jenkins@googlemail.com>
+***/
+
+#include <errno.h>
+#include <fnmatch.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include "sd-hwdb.h"
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "hashmap.h"
+#include "hwdb-internal.h"
+#include "nulstr-util.h"
+#include "string-util.h"
+#include "time-util.h"
+
+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_child(sd_hwdb *hwdb, const struct trie_node_f *node, size_t idx) {
+ const char *base = (const char *)node;
+
+ base += le64toh(hwdb->head->node_size);
+ base += idx * le64toh(hwdb->head->child_entry_size);
+ return (const struct trie_child_entry_f *)base;
+}
+
+static const struct trie_value_entry_f *trie_node_value(sd_hwdb *hwdb, const struct trie_node_f *node, size_t idx) {
+ const char *base = (const char *)node;
+
+ base += le64toh(hwdb->head->node_size);
+ base += node->children_count * le64toh(hwdb->head->child_entry_size);
+ base += idx * le64toh(hwdb->head->value_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, (const char *)node + le64toh(hwdb->head->node_size), 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 struct trie_value_entry_f *entry) {
+ const char *key;
+ int r;
+
+ assert(hwdb);
+
+ key = trie_string(hwdb, entry->key_off);
+
+ /*
+ * Silently ignore all properties which do not start with a
+ * space; future extensions might use additional prefixes.
+ */
+ if (key[0] != ' ')
+ return 0;
+
+ key++;
+
+ if (le64toh(hwdb->head->value_entry_size) >= sizeof(struct trie_value_entry2_f)) {
+ const struct trie_value_entry2_f *old, *entry2;
+
+ entry2 = (const struct trie_value_entry2_f *)entry;
+ old = ordered_hashmap_get(hwdb->properties, key);
+ if (old) {
+ /* On duplicates, we order by filename priority and line-number.
+ *
+ * v2 of the format had 64 bits for the line number.
+ * v3 reuses top 32 bits of line_number to store the priority.
+ * We check the top bits — if they are zero we have v2 format.
+ * This means that v2 clients will print wrong line numbers with
+ * v3 data.
+ *
+ * For v3 data: we compare the priority (of the source file)
+ * and the line number.
+ *
+ * For v2 data: we rely on the fact that the filenames in the hwdb
+ * are added in the order of priority (higher later), because they
+ * are *processed* in the order of priority. So we compare the
+ * indices to determine which file had higher priority. Comparing
+ * the strings alphabetically would be useless, because those are
+ * full paths, and e.g. /usr/lib would sort after /etc, even
+ * though it has lower priority. This is not reliable because of
+ * suffix compression, but should work for the most common case of
+ * /usr/lib/udev/hwbd.d and /etc/udev/hwdb.d, and is better than
+ * not doing the comparison at all.
+ */
+ bool lower;
+
+ if (entry2->file_priority == 0)
+ lower = entry2->filename_off < old->filename_off ||
+ (entry2->filename_off == old->filename_off && entry2->line_number < old->line_number);
+ else
+ lower = entry2->file_priority < old->file_priority ||
+ (entry2->file_priority == old->file_priority && entry2->line_number < old->line_number);
+ if (lower)
+ return 0;
+ }
+ }
+
+ r = ordered_hashmap_ensure_allocated(&hwdb->properties, &string_hash_ops);
+ if (r < 0)
+ return r;
+
+ r = ordered_hashmap_replace(hwdb->properties, key, (void *)entry);
+ 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_child(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_node_value(hwdb, node, i));
+ 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) {
+ char c;
+
+ for (; (c = trie_string(hwdb, node->prefix_off)[p]); p++) {
+ if (IN_SET(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_node_value(hwdb, node, n));
+ if (err < 0)
+ return err;
+ }
+ return 0;
+ }
+
+ child = node_lookup_f(hwdb, node, search[i]);
+ node = child;
+ i++;
+ }
+ return 0;
+}
+
+static int hwdb_new(const char *path, sd_hwdb **ret) {
+ _cleanup_(sd_hwdb_unrefp) sd_hwdb *hwdb = NULL;
+ const char sig[] = HWDB_SIG;
+
+ assert_return(ret, -EINVAL);
+
+ hwdb = new0(sd_hwdb, 1);
+ if (!hwdb)
+ return -ENOMEM;
+
+ hwdb->n_ref = 1;
+
+ /* Find hwdb.bin in the explicit path if provided, or iterate over hwdb_bin_paths otherwise */
+ if (!isempty(path)) {
+ log_debug("Trying to open \"%s\"...", path);
+ hwdb->f = fopen(path, "re");
+ if (!hwdb->f)
+ return log_debug_errno(errno, "Failed to open %s: %m", path);
+ } else {
+ NULSTR_FOREACH(p, hwdb_bin_paths) {
+ log_debug("Trying to open \"%s\"...", p);
+ hwdb->f = fopen(p, "re");
+ if (hwdb->f) {
+ path = p;
+ break;
+ }
+ if (errno != ENOENT)
+ return log_debug_errno(errno, "Failed to open %s: %m", p);
+ }
+
+ if (!hwdb->f)
+ return log_debug_errno(SYNTHETIC_ERRNO(ENOENT),
+ "hwdb.bin does not exist, please run 'systemd-hwdb update'");
+ }
+
+ if (fstat(fileno(hwdb->f), &hwdb->st) < 0)
+ return log_debug_errno(errno, "Failed to stat %s: %m", path);
+ if (hwdb->st.st_size < (off_t) offsetof(struct trie_header_f, strings_len) + 8)
+ return log_debug_errno(SYNTHETIC_ERRNO(EIO), "File %s is too short: %m", path);
+ if (file_offset_beyond_memory_size(hwdb->st.st_size))
+ return log_debug_errno(SYNTHETIC_ERRNO(EFBIG), "File %s is too long: %m", 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, "Failed to map %s: %m", path);
+
+ if (memcmp(hwdb->map, sig, sizeof(hwdb->head->signature)) != 0 ||
+ (size_t) hwdb->st.st_size != le64toh(hwdb->head->file_size))
+ return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Failed to recognize the format of %s", path);
+
+ 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 = TAKE_PTR(hwdb);
+
+ return 0;
+}
+
+_public_ int sd_hwdb_new_from_path(const char *path, sd_hwdb **ret) {
+ assert_return(!isempty(path), -EINVAL);
+
+ return hwdb_new(path, ret);
+}
+
+_public_ int sd_hwdb_new(sd_hwdb **ret) {
+ return hwdb_new(NULL, ret);
+}
+
+static sd_hwdb *hwdb_free(sd_hwdb *hwdb) {
+ assert(hwdb);
+
+ if (hwdb->map)
+ munmap((void *)hwdb->map, hwdb->st.st_size);
+ safe_fclose(hwdb->f);
+ ordered_hashmap_free(hwdb->properties);
+ return mfree(hwdb);
+}
+
+DEFINE_PUBLIC_TRIVIAL_REF_UNREF_FUNC(sd_hwdb, sd_hwdb, hwdb_free)
+
+static int properties_prepare(sd_hwdb *hwdb, const char *modalias) {
+ assert(hwdb);
+ assert(modalias);
+
+ ordered_hashmap_clear(hwdb->properties);
+ hwdb->properties_modified = true;
+
+ return trie_search_f(hwdb, modalias);
+}
+
+_public_ int sd_hwdb_get(sd_hwdb *hwdb, const char *modalias, const char *key, const char **_value) {
+ const struct trie_value_entry_f *entry;
+ 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;
+
+ entry = ordered_hashmap_get(hwdb->properties, key);
+ if (!entry)
+ return -ENOENT;
+
+ *_value = trie_string(hwdb, entry->value_off);
+
+ 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 struct trie_value_entry_f *entry;
+ const void *k;
+
+ assert_return(hwdb, -EINVAL);
+ assert_return(key, -EINVAL);
+ assert_return(value, -EINVAL);
+
+ if (hwdb->properties_modified)
+ return -EAGAIN;
+
+ if (!ordered_hashmap_iterate(hwdb->properties, &hwdb->properties_iterator, (void **)&entry, &k))
+ return 0;
+
+ *key = k;
+ *value = trie_string(hwdb, entry->value_off);
+
+ return 1;
+}
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