libudev-device-private.c revision c8f8394a9309d4390daac70b736b34d0b6734f95
/*
* libudev - interface to udev device information
*
* Copyright (C) 2008-2010 Kay Sievers <kay.sievers@vrfy.org>
*
* This library 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.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stddef.h>
#include <stdbool.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include "libudev.h"
#include "libudev-private.h"
static void udev_device_tag(struct udev_device *dev, const char *tag, bool add)
{
const char *id;
char filename[UTIL_PATH_SIZE];
id = udev_device_get_id_filename(dev);
if (id == NULL)
return;
util_strscpyl(filename, sizeof(filename), TEST_PREFIX "/run/udev/tags/", tag, "/", id, NULL);
if (add) {
int fd;
mkdir_parents(filename, 0755);
fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
if (fd >= 0)
close(fd);
} else {
unlink(filename);
}
}
int udev_device_tag_index(struct udev_device *dev, struct udev_device *dev_old, bool add)
{
struct udev_list_entry *list_entry;
bool found;
if (add && dev_old != NULL) {
/* delete possible left-over tags */
udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(dev_old)) {
const char *tag_old = udev_list_entry_get_name(list_entry);
struct udev_list_entry *list_entry_current;
found = false;
udev_list_entry_foreach(list_entry_current, udev_device_get_tags_list_entry(dev)) {
const char *tag = udev_list_entry_get_name(list_entry_current);
if (streq(tag, tag_old)) {
found = true;
break;
}
}
if (!found)
udev_device_tag(dev_old, tag_old, false);
}
}
udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(dev))
udev_device_tag(dev, udev_list_entry_get_name(list_entry), add);
return 0;
}
static bool device_has_info(struct udev_device *udev_device)
{
struct udev_list_entry *list_entry;
if (udev_device_get_devlinks_list_entry(udev_device) != NULL)
return true;
if (udev_device_get_devlink_priority(udev_device) != 0)
return true;
udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device))
if (udev_list_entry_get_num(list_entry))
return true;
if (udev_device_get_tags_list_entry(udev_device) != NULL)
return true;
if (udev_device_get_watch_handle(udev_device) >= 0)
return true;
return false;
}
int udev_device_update_db(struct udev_device *udev_device)
{
struct udev *udev = udev_device_get_udev(udev_device);
bool has_info;
const char *id;
char filename[UTIL_PATH_SIZE];
char filename_tmp[UTIL_PATH_SIZE];
FILE *f;
id = udev_device_get_id_filename(udev_device);
if (id == NULL)
return -1;
has_info = device_has_info(udev_device);
util_strscpyl(filename, sizeof(filename), TEST_PREFIX "/run/udev/data/", id, NULL);
/* do not store anything for otherwise empty devices */
if (!has_info &&
major(udev_device_get_devnum(udev_device)) == 0 &&
udev_device_get_ifindex(udev_device) == 0) {
unlink(filename);
return 0;
}
/* write a database file */
util_strscpyl(filename_tmp, sizeof(filename_tmp), filename, ".tmp", NULL);
mkdir_parents(filename_tmp, 0755);
f = fopen(filename_tmp, "we");
if (f == NULL) {
udev_err(udev, "unable to create temporary db file '%s': %m\n", filename_tmp);
return -1;
}
/*
* set 'sticky' bit to indicate that we should not clean the
* database when we transition from initramfs to the real root
*/
if (udev_device_get_db_persist(udev_device))
fchmod(fileno(f), 01644);
if (has_info) {
struct udev_list_entry *list_entry;
if (major(udev_device_get_devnum(udev_device)) > 0) {
udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(udev_device))
fprintf(f, "S:%s\n", udev_list_entry_get_name(list_entry) + strlen(TEST_PREFIX "/dev/"));
if (udev_device_get_devlink_priority(udev_device) != 0)
fprintf(f, "L:%i\n", udev_device_get_devlink_priority(udev_device));
if (udev_device_get_watch_handle(udev_device) >= 0)
fprintf(f, "W:%i\n", udev_device_get_watch_handle(udev_device));
}
if (udev_device_get_usec_initialized(udev_device) > 0)
fprintf(f, "I:%llu\n", udev_device_get_usec_initialized(udev_device));
udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
if (!udev_list_entry_get_num(list_entry))
continue;
fprintf(f, "E:%s=%s\n",
udev_list_entry_get_name(list_entry),
udev_list_entry_get_value(list_entry));
}
udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
fprintf(f, "G:%s\n", udev_list_entry_get_name(list_entry));
}
fclose(f);
rename(filename_tmp, filename);
udev_dbg(udev, "created %s file '%s' for '%s'\n", has_info ? "db" : "empty",
filename, udev_device_get_devpath(udev_device));
return 0;
}
int udev_device_delete_db(struct udev_device *udev_device)
{
const char *id;
char filename[UTIL_PATH_SIZE];
id = udev_device_get_id_filename(udev_device);
if (id == NULL)
return -1;
util_strscpyl(filename, sizeof(filename), TEST_PREFIX "/run/udev/data/", id, NULL);
unlink(filename);
return 0;
}