libudev-device-db-write.c revision 065db052211d3bf08d9b0f698a79a8798faf11d2
/*
* libudev - interface to udev device information
*
* Copyright (C) 2008 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 <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include "udev.h"
static size_t devpath_to_db_path(struct udev *udev, const char *devpath, char *filename, size_t len)
{
char *s;
size_t l;
s = filename;
l = util_strpcpyl(&s, len, udev_get_dev_path(udev), "/.udev/db/", NULL);
return util_path_encode(devpath, filename, l);
}
int udev_device_update_db(struct udev_device *udev_device)
{
struct udev *udev = udev_device_get_udev(udev_device);
char filename[UTIL_PATH_SIZE];
FILE *f;
char target[232]; /* on 64bit, tmpfs inlines up to 239 bytes */
size_t devlen = strlen(udev_get_dev_path(udev))+1;
char *s;
size_t l;
struct udev_list_entry *list_entry;
int ret;
devpath_to_db_path(udev, udev_device_get_devpath(udev_device), filename, sizeof(filename));
util_create_path(udev, filename);
unlink(filename);
udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device))
if (udev_list_entry_get_flag(list_entry))
goto file;
if (udev_device_get_num_fake_partitions(udev_device) != 0)
goto file;
if (udev_device_get_ignore_remove(udev_device))
goto file;
if (udev_device_get_devlink_priority(udev_device) != 0)
goto file;
if (udev_device_get_event_timeout(udev_device) >= 0)
goto file;
if (udev_device_get_watch_handle(udev_device) >= 0)
goto file;
if (udev_device_get_devnode(udev_device) == NULL)
goto out;
/*
* if we have only the node and symlinks to store, try not to waste
* tmpfs memory -- store values, if they fit, in a symlink target
*/
s = target;
l = util_strpcpy(&s, sizeof(target), &udev_device_get_devnode(udev_device)[devlen]);
udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(udev_device)) {
l = util_strpcpyl(&s, l, " ", &udev_list_entry_get_name(list_entry)[devlen], NULL);
if (l == 0) {
info(udev, "size of links too large, create file\n");
goto file;
}
}
info(udev, "create db link (%s)\n", target);
udev_selinux_setfscreatecon(udev, filename, S_IFLNK);
ret = symlink(target, filename);
udev_selinux_resetfscreatecon(udev);
if (ret == 0)
goto out;
file:
f = fopen(filename, "w");
if (f == NULL) {
err(udev, "unable to create db file '%s': %m\n", filename);
return -1;
}
info(udev, "created db file for '%s' in '%s'\n", udev_device_get_devpath(udev_device), filename);
if (udev_device_get_devnode(udev_device) != NULL) {
fprintf(f, "N:%s\n", &udev_device_get_devnode(udev_device)[devlen]);
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)[devlen]);
}
if (udev_device_get_devlink_priority(udev_device) != 0)
fprintf(f, "L:%u\n", udev_device_get_devlink_priority(udev_device));
if (udev_device_get_event_timeout(udev_device) >= 0)
fprintf(f, "T:%u\n", udev_device_get_event_timeout(udev_device));
if (udev_device_get_num_fake_partitions(udev_device) != 0)
fprintf(f, "A:%u\n", udev_device_get_num_fake_partitions(udev_device));
if (udev_device_get_ignore_remove(udev_device))
fprintf(f, "R:%u\n", udev_device_get_ignore_remove(udev_device));
if (udev_device_get_watch_handle(udev_device) >= 0)
fprintf(f, "W:%u\n", udev_device_get_watch_handle(udev_device));
udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
if (!udev_list_entry_get_flag(list_entry))
continue;
fprintf(f, "E:%s=%s\n",
udev_list_entry_get_name(list_entry),
udev_list_entry_get_value(list_entry));
}
fclose(f);
out:
return 0;
}
int udev_device_delete_db(struct udev_device *udev_device)
{
struct udev *udev = udev_device_get_udev(udev_device);
char filename[UTIL_PATH_SIZE];
devpath_to_db_path(udev, udev_device_get_devpath(udev_device), filename, sizeof(filename));
unlink(filename);
return 0;
}
int udev_device_rename_db(struct udev_device *udev_device, const char *devpath_old)
{
struct udev *udev = udev_device_get_udev(udev_device);
char filename_old[UTIL_PATH_SIZE];
char filename[UTIL_PATH_SIZE];
devpath_to_db_path(udev, devpath_old, filename_old, sizeof(filename_old));
devpath_to_db_path(udev, udev_device_get_devpath(udev_device), filename, sizeof(filename));
return rename(filename_old, filename);
}