#include <stdio.h>

#include <errno.h>

#include <string.h>

#include <inttypes.h>

#include <ctype.h>

#include <stdlib.h>

#include <fnmatch.h>

#include <getopt.h>

#include <sys/mman.h>

#include "libudev-private.h"

#include "libudev-hwdb-def.h"

struct udev_hwdb {

struct udev *udev;

int refcount;

FILE *f;

struct stat st;

union {

struct trie_header_f *head;

const char *map;

};

struct udev_list properties_list;

};

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(struct udev_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(struct udev_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(struct udev_hwdb *hwdb, le64_t off) {

return (const struct trie_node_f *)(hwdb->map + le64toh(off));

}

static const char *trie_string(struct udev_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(struct udev_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(struct udev_hwdb *hwdb, const char *key, const char *value) {

/* TODO: add sub-matches (+) against DMI data */

if (key[0] != ' ')

return 0;

if (udev_list_entry_add(&hwdb->properties_list, key+1, value) == NULL)

return -ENOMEM;

return 0;

}

static int trie_fnmatch_f(struct udev_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(struct udev_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;

}

_public_ struct udev_hwdb *udev_hwdb_new(struct udev *udev) {

struct udev_hwdb *hwdb;

const char sig[] = HWDB_SIG;

hwdb = new0(struct udev_hwdb, 1);

if (!hwdb)

return NULL;

hwdb->refcount = 1;

udev_list_init(udev, &hwdb->properties_list, true);

hwdb->f = fopen("/etc/udev/hwdb.bin", "re");

if (!hwdb->f) {

log_debug("error reading /etc/udev/hwdb.bin: %m");

udev_hwdb_unref(hwdb);

return NULL;

}

if (fstat(fileno(hwdb->f), &hwdb->st) < 0 ||

(size_t)hwdb->st.st_size < offsetof(struct trie_header_f, strings_len) + 8) {

log_debug("error reading /etc/udev/hwdb.bin: %m");

udev_hwdb_unref(hwdb);

return NULL;

}

hwdb->map = mmap(0, hwdb->st.st_size, PROT_READ, MAP_SHARED, fileno(hwdb->f), 0);

if (hwdb->map == MAP_FAILED) {

log_debug("error mapping /etc/udev/hwdb.bin: %m");

udev_hwdb_unref(hwdb);

return NULL;

}

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 /etc/udev/hwdb.bin");

udev_hwdb_unref(hwdb);

return NULL;

}

log_debug("=== trie on-disk ===\n");

log_debug("tool version: %llu", (unsigned long long)le64toh(hwdb->head->tool_version));

log_debug("file size: %8llu bytes\n", (unsigned long long)hwdb->st.st_size);

log_debug("header size %8llu bytes\n", (unsigned long long)le64toh(hwdb->head->header_size));

log_debug("strings %8llu bytes\n", (unsigned long long)le64toh(hwdb->head->strings_len));

log_debug("nodes %8llu bytes\n", (unsigned long long)le64toh(hwdb->head->nodes_len));

return hwdb;

}

_public_ struct udev_hwdb *udev_hwdb_ref(struct udev_hwdb *hwdb) {

if (!hwdb)

return NULL;

hwdb->refcount++;

return hwdb;

}

_public_ struct udev_hwdb *udev_hwdb_unref(struct udev_hwdb *hwdb) {

if (!hwdb)

return NULL;

hwdb->refcount--;

if (hwdb->refcount > 0)

return hwdb;

if (hwdb->map)

munmap((void *)hwdb->map, hwdb->st.st_size);

if (hwdb->f)

fclose(hwdb->f);

udev_list_cleanup(&hwdb->properties_list);

free(hwdb);

return NULL;

}

bool udev_hwdb_validate(struct udev_hwdb *hwdb) {

struct stat st;

if (!hwdb)

return false;

if (!hwdb->f)

return false;

if (fstat(fileno(hwdb->f), &st) < 0)

return true;

if (timespec_load(&hwdb->st.st_mtim) != timespec_load(&st.st_mtim))

return true;

return false;

}

_public_ struct udev_list_entry *udev_hwdb_get_properties_list_entry(struct udev_hwdb *hwdb, const char *modalias, unsigned int flags) {

int err;

if (!hwdb || !hwdb->f) {

errno = EINVAL;

return NULL;

}

udev_list_cleanup(&hwdb->properties_list);

err = trie_search_f(hwdb, modalias);

if (err < 0) {

errno = -err;

return NULL;

}

return udev_list_get_entry(&hwdb->properties_list);

}