#include <stdlib.h>

#include <unistd.h>

#include <getopt.h>

#include <string.h>

#include "util.h"

#include "strbuf.h"

#include "conf-files.h"

#include "udev.h"

#include "udev-hwdb.h"

static const char * const conf_file_dirs[] = {

SYSCONFDIR "/udev/hwdb.d",

UDEVLIBEXECDIR "/hwdb.d",

NULL

};

struct trie {

struct trie_node *root;

struct strbuf *strings;

size_t nodes_count;

size_t children_count;

size_t values_count;

};

struct trie_node {

/* prefix, common part for all children of this node */

size_t prefix_off;

/* sorted array of pointers to children nodes */

struct trie_child_entry *children;

uint8_t children_count;

/* sorted array of key/value pairs */

struct trie_value_entry *values;

size_t values_count;

};

struct trie_child_entry {

uint8_t c;

struct trie_node *child;

};

struct trie_value_entry {

size_t key_off;

size_t value_off;

};

static int trie_children_cmp(const void *v1, const void *v2) {

const struct trie_child_entry *n1 = v1;

const struct trie_child_entry *n2 = v2;

return n1->c - n2->c;

}

static int node_add_child(struct trie *trie, struct trie_node *node, struct trie_node *node_child, uint8_t c) {

struct trie_child_entry *child;

int err = 0;

/* extend array, add new entry, sort for bisection */

child = realloc(node->children, (node->children_count + 1) * sizeof(struct trie_child_entry));

if (!child) {

err = -ENOMEM;

goto out;

}

node->children = child;

trie->children_count++;

node->children[node->children_count].c = c;

node->children[node->children_count].child = node_child;

node->children_count++;

qsort(node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);

trie->nodes_count++;

out:

return err;

}

static struct trie_node *node_lookup(const struct trie_node *node, uint8_t c) {

struct trie_child_entry *child;

struct trie_child_entry search;

search.c = c;

child = bsearch(&search, node->children, node->children_count, sizeof(struct trie_child_entry), trie_children_cmp);

if (child)

return child->child;

return NULL;

}

static void trie_node_cleanup(struct trie_node *node) {

size_t i;

for (i = 0; i < node->children_count; i++)

trie_node_cleanup(node->children[i].child);

free(node->children);

free(node->values);

free(node);

}

static int trie_values_cmp(const void *v1, const void *v2, void *arg) {

const struct trie_value_entry *val1 = v1;

const struct trie_value_entry *val2 = v2;

struct trie *trie = arg;

return strcmp(trie->strings->buf + val1->key_off,

trie->strings->buf + val2->key_off);

}

static int trie_node_add_value(struct trie *trie, struct trie_node *node,

const char *key, const char *value) {

size_t k, v;

struct trie_value_entry *val;

struct trie_value_entry search;

k = strbuf_add_string(trie->strings, key, strlen(key));

v = strbuf_add_string(trie->strings, value, strlen(value));

/* replace existing earlier key with new value */

search.value_off = k;

val = xbsearch_r(&search, node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);

if (val) {

val->value_off = v;

return 0;

}

/* extend array, add new entry, sort for bisection */

val = realloc(node->values, (node->values_count + 1) * sizeof(struct trie_value_entry));

if (!val)

return -ENOMEM;

trie->values_count++;

node->values = val;

node->values[node->values_count].key_off = k;

node->values[node->values_count].value_off = v;

node->values_count++;

qsort_r(node->values, node->values_count, sizeof(struct trie_value_entry), trie_values_cmp, trie);

return 0;

}

static int trie_insert(struct trie *trie, struct trie_node *node, const char *search,

const char *key, const char *value) {

size_t i = 0;

int err = 0;

for (;;) {

size_t p;

uint8_t c;

struct trie_node *child;

for (p = 0; (c = trie->strings->buf[node->prefix_off + p]); p++) {

char *s;

ssize_t off;

if (c == search[i + p])

continue;

/* split node */

child = calloc(sizeof(struct trie_node), 1);

if (!child) {

err = -ENOMEM;

goto out;

}

/* move values from parent to child */

child->prefix_off = node->prefix_off + p+1;

child->children = node->children;

child->children_count = node->children_count;

child->values = node->values;

child->values_count = node->values_count;

/* update parent; use strdup() because the source gets realloc()d */

s = strndup(trie->strings->buf + node->prefix_off, p);

if (!s) {

err = -ENOMEM;

goto out;

}

off = strbuf_add_string(trie->strings, s, p);

free(s);

if (off < 0) {

err = off;

goto out;

}

node->prefix_off = off;

node->children = NULL;

node->children_count = 0;

node->values = NULL;

node->values_count = 0;

err = node_add_child(trie, node, child, c);

if (err)

goto out;

break;

}

i += p;

c = search[i];

if (c == '\0')

return trie_node_add_value(trie, node, key, value);

child = node_lookup(node, c);

if (!child) {

ssize_t off;

/* new child */

child = calloc(sizeof(struct trie_node), 1);

if (!child) {

err = -ENOMEM;

goto out;

}

off = strbuf_add_string(trie->strings, search + i+1, strlen(search + i+1));

if (off < 0) {

err = off;

goto out;

}

child->prefix_off = off;

err = node_add_child(trie, node, child, c);

if (err)

goto out;

return trie_node_add_value(trie, child, key, value);

}

node = child;

i++;

}

out:

return err;

}

struct trie_f {

FILE *f;

struct trie *trie;

uint64_t strings_off;

uint64_t nodes_count;

uint64_t children_count;

uint64_t values_count;

};

static void trie_store_nodes_size(struct trie_f *trie, struct trie_node *node) {

uint64_t i;

for (i = 0; i < node->children_count; i++)

trie_store_nodes_size(trie, node->children[i].child);

trie->strings_off += sizeof(struct trie_node_f);

for (i = 0; i < node->children_count; i++)

trie->strings_off += sizeof(struct trie_child_entry_f);

for (i = 0; i < node->values_count; i++)

trie->strings_off += sizeof(struct trie_value_entry_f);

}

static int64_t trie_store_nodes(struct trie_f *trie, struct trie_node *node) {

uint64_t i;

struct trie_node_f n = {

.prefix_off = htole64(trie->strings_off + node->prefix_off),

.children_count = node->children_count,

.values_count = htole64(node->values_count),

};

struct trie_child_entry_f *children;

int64_t node_off;

if (node->children_count) {

children = new0(struct trie_child_entry_f, node->children_count);

if (!children)

return -ENOMEM;

}

/* post-order recursion */

for (i = 0; i < node->children_count; i++) {

int64_t child_off;

child_off = trie_store_nodes(trie, node->children[i].child);

if (child_off < 0)

return child_off;

children[i].c = node->children[i].c;

children[i].child_off = htole64(child_off);

}

/* write node */

node_off = ftello(trie->f);

fwrite(&n, sizeof(struct trie_node_f), 1, trie->f);

trie->nodes_count++;

/* append children array */

if (node->children_count) {

fwrite(children, sizeof(struct trie_child_entry_f), node->children_count, trie->f);

trie->children_count += node->children_count;

free(children);

}

/* append values array */

for (i = 0; i < node->values_count; i++) {

struct trie_value_entry_f v = {

.key_off = htole64(trie->strings_off + node->values[i].key_off),

.value_off = htole64(trie->strings_off + node->values[i].value_off),

};

fwrite(&v, sizeof(struct trie_value_entry_f), 1, trie->f);

trie->values_count++;

}

return node_off;

}

static int trie_store(struct trie *trie, const char *filename) {

struct trie_f t = {

.trie = trie,

};

char *filename_tmp;

int64_t pos;

int64_t root_off;

int64_t size;

struct trie_header_f h = {

.signature = HWDB_SIG,

.tool_version = htole64(atoi(VERSION)),

.header_size = htole64(sizeof(struct trie_header_f)),

.node_size = htole64(sizeof(struct trie_node_f)),

.child_entry_size = htole64(sizeof(struct trie_child_entry_f)),

.value_entry_size = htole64(sizeof(struct trie_value_entry_f)),

};

int err;

/* calculate size of header, nodes, children entries, value entries */

t.strings_off = sizeof(struct trie_header_f);

trie_store_nodes_size(&t, trie->root);

err = fopen_temporary(filename , &t.f, &filename_tmp);

if (err < 0)

return err;

fchmod(fileno(t.f), 0444);

/* write nodes */

fseeko(t.f, sizeof(struct trie_header_f), SEEK_SET);

root_off = trie_store_nodes(&t, trie->root);

h.nodes_root_off = htole64(root_off);

pos = ftello(t.f);

h.nodes_len = htole64(pos - sizeof(struct trie_header_f));

/* write string buffer */

fwrite(trie->strings->buf, trie->strings->len, 1, t.f);

h.strings_len = htole64(trie->strings->len);

/* write header */

size = ftello(t.f);

h.file_size = htole64(size);

fseeko(t.f, 0, SEEK_SET);

fwrite(&h, sizeof(struct trie_header_f), 1, t.f);

err = ferror(t.f);

if (err)

err = -errno;

fclose(t.f);

if (err < 0 || rename(filename_tmp, filename) < 0) {

unlink(filename_tmp);

goto out;

}

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

log_debug("size: %8zi bytes\n", size);

log_debug("header: %8zu bytes\n", sizeof(struct trie_header_f));

log_debug("nodes: %8zu bytes (%8zi)\n", t.nodes_count * sizeof(struct trie_node_f), t.nodes_count);

log_debug("child pointers: %8zu bytes (%8zi)\n", t.children_count * sizeof(struct trie_child_entry_f), t.children_count);

log_debug("value pointers: %8zu bytes (%8zi)\n", t.values_count * sizeof(struct trie_value_entry_f), t.values_count);

log_debug("string store: %8zu bytes\n", trie->strings->len);

log_debug("strings start: %8llu\n", (unsigned long long) t.strings_off);

out:

free(filename_tmp);

return err;

}

static int import_file(struct trie *trie, const char *filename) {

FILE *f;

char line[LINE_MAX];

char match[LINE_MAX];

f = fopen(filename, "re");

if (f == NULL)

return -errno;

match[0] = '\0';

while (fgets(line, sizeof(line), f)) {

size_t len;

if (line[0] == '#')

continue;

/* new line, new record */

if (line[0] == '\n') {

match[0] = '\0';

continue;

}

/* remove newline */

len = strlen(line);

if (len < 2)

continue;

line[len-1] = '\0';

/* start of new record */

if (match[0] == '\0') {

strcpy(match, line);

continue;

}

/* value lines */

if (line[0] == ' ') {

char *value;

value = strchr(line, '=');

if (!value)

continue;

value[0] = '\0';

value++;

trie_insert(trie, trie->root, match, line, value);

}

}

fclose(f);

return 0;

}

static void help(void) {

printf("Usage: udevadm hwdb [--create] [--help]\n"

" --update update the hardware database\n"

" --help\n\n");

}

static int adm_hwdb(struct udev *udev, int argc, char *argv[]) {

static const struct option options[] = {

{ "update", no_argument, NULL, 'u' },

{ "help", no_argument, NULL, 'h' },

{}

};

bool update = false;

struct trie *trie;

char **files, **f;

int err;

int rc = EXIT_SUCCESS;

for (;;) {

int option;

option = getopt_long(argc, argv, "ch", options, NULL);

if (option == -1)

break;

switch (option) {

case 'u':

update = true;

break;

case 'h':

help();

return EXIT_SUCCESS;

}

}

if (!update) {

help();

return EXIT_SUCCESS;

}

trie = calloc(sizeof(struct trie), 1);

if (!trie) {

rc = EXIT_FAILURE;

goto out;

}

/* string store */

trie->strings = strbuf_new();

if (!trie->strings) {

rc = EXIT_FAILURE;

goto out;

}

/* index */

trie->root = calloc(sizeof(struct trie_node), 1);

if (!trie->root) {

rc = EXIT_FAILURE;

goto out;

}

trie->nodes_count++;

err = conf_files_list_strv(&files, ".hwdb", (const char **)conf_file_dirs);

if (err < 0) {

log_error("failed to enumerate hwdb files: %s\n", strerror(-err));

rc = EXIT_FAILURE;

goto out;

}

STRV_FOREACH(f, files) {

log_debug("reading file '%s'", *f);

import_file(trie, *f);

}

strv_free(files);

strbuf_complete(trie->strings);

log_debug("=== trie in-memory ===\n");

log_debug("nodes: %8zu bytes (%8zu)\n", trie->nodes_count * sizeof(struct trie_node), trie->nodes_count);

log_debug("children arrays: %8zu bytes (%8zu)\n", trie->children_count * sizeof(struct trie_child_entry), trie->children_count);

log_debug("values arrays: %8zu bytes (%8zu)\n", trie->values_count * sizeof(struct trie_value_entry), trie->values_count);

log_debug("strings: %8zu bytes\n", trie->strings->len);

log_debug("strings incoming: %8zu bytes (%8zu)\n", trie->strings->in_len, trie->strings->in_count);

log_debug("strings dedup'ed: %8zu bytes (%8zu)\n", trie->strings->dedup_len, trie->strings->dedup_count);

mkdir_parents(SYSCONFDIR "/udev/hwdb.bin", 0755);

err = trie_store(trie, SYSCONFDIR "/udev/hwdb.bin");

if (err < 0) {

log_error("Failure writing hardware database '%s': %s", SYSCONFDIR "/udev/hwdb.bin", strerror(-err));

rc = EXIT_FAILURE;

}

out:

if (trie->root)

trie_node_cleanup(trie->root);

strbuf_cleanup(trie->strings);

free(trie);

return rc;

}

const struct udevadm_cmd udevadm_hwdb = {

.name = "hwdb",

.cmd = adm_hwdb,

.help = "maintain the hardware database index",

};