udev_device.c revision ff9a488d8c559a2ee40e522cdc68b750670711e4
/*
* udev_device.c - main udev data object
*
* Copyright (C) 2004-2006 Kay Sievers <kay.sievers@vrfy.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <stropts.h>
#include <net/if.h>
#include <linux/sockios.h>
#include "udev.h"
#include "udev_rules.h"
struct udevice *udev_device_init(void)
{
struct udevice *udev;
udev = malloc(sizeof(struct udevice));
if (udev == NULL)
return NULL;
memset(udev, 0x00, sizeof(struct udevice));
INIT_LIST_HEAD(&udev->symlink_list);
INIT_LIST_HEAD(&udev->run_list);
INIT_LIST_HEAD(&udev->env_list);
/* set sysfs device to local storage, can be overridden if needed */
udev->dev = &udev->dev_local;
/* default node permissions */
udev->mode = 0660;
strcpy(udev->owner, "root");
strcpy(udev->group, "root");
return udev;
}
void udev_device_cleanup(struct udevice *udev)
{
name_list_cleanup(&udev->symlink_list);
name_list_cleanup(&udev->run_list);
name_list_cleanup(&udev->env_list);
free(udev);
}
dev_t udev_device_get_devt(struct udevice *udev)
{
const char *attr;
unsigned int major, minor;
/* read it from sysfs */
attr = sysfs_attr_get_value(udev->dev->devpath, "dev");
if (attr != NULL) {
if (sscanf(attr, "%u:%u", &major, &minor) == 2)
return makedev(major, minor);
}
return makedev(0, 0);
}
static int rename_net_if(struct udevice *udev)
{
int sk;
struct ifreq ifr;
int retval;
info("changing net interface name from '%s' to '%s'", udev->dev->kernel_name, udev->name);
if (udev->test_run)
return 0;
sk = socket(PF_INET, SOCK_DGRAM, 0);
if (sk < 0) {
err("error opening socket: %s", strerror(errno));
return -1;
}
memset(&ifr, 0x00, sizeof(struct ifreq));
strlcpy(ifr.ifr_name, udev->dev->kernel_name, IFNAMSIZ);
strlcpy(ifr.ifr_newname, udev->name, IFNAMSIZ);
retval = ioctl(sk, SIOCSIFNAME, &ifr);
if (retval != 0)
err("error changing net interface name: %s", strerror(errno));
close(sk);
return retval;
}
int udev_device_event(struct udev_rules *rules, struct udevice *udev)
{
int retval = 0;
/* add device node */
if (major(udev->devt) != 0 && strcmp(udev->action, "add") == 0) {
struct udevice *udev_old;
dbg("device node add '%s'", udev->dev->devpath);
udev_rules_get_name(rules, udev);
if (udev->ignore_device) {
info("device event will be ignored");
goto exit;
}
if (udev->name[0] == '\0') {
info("device node creation supressed");
goto exit;
}
/* read current database entry, we may want to cleanup symlinks */
udev_old = udev_device_init();
if (udev_old != NULL) {
if (udev_db_get_device(udev_old, udev->dev->devpath) == 0) {
info("device '%s' already known, remove possible symlinks", udev->dev->devpath);
udev_node_remove_symlinks(udev_old);
}
udev_device_cleanup(udev_old);
}
/* create node and symlinks, store record in database */
retval = udev_node_add(udev, udev_old);
if (retval == 0)
udev_db_add_device(udev);
goto exit;
}
/* add netif */
if (strcmp(udev->dev->subsystem, "net") == 0 && strcmp(udev->action, "add") == 0) {
dbg("netif add '%s'", udev->dev->devpath);
udev_rules_get_name(rules, udev);
if (udev->ignore_device) {
info("device event will be ignored");
goto exit;
}
/* look if we want to change the name of the netif */
if (strcmp(udev->name, udev->dev->kernel_name) != 0) {
char *pos;
retval = rename_net_if(udev);
if (retval != 0)
goto exit;
info("renamed netif to '%s'", udev->name);
/* export old name */
setenv("INTERFACE_OLD", udev->dev->kernel_name, 1);
/* now fake the devpath, because the kernel name changed silently */
pos = strrchr(udev->dev->devpath, '/');
if (pos != NULL) {
pos[1] = '\0';
strlcat(udev->dev->devpath, udev->name, sizeof(udev->dev->devpath));
strlcpy(udev->dev->kernel_name, udev->name, sizeof(udev->dev->kernel_name));
setenv("DEVPATH", udev->dev->devpath, 1);
setenv("INTERFACE", udev->name, 1);
}
}
goto exit;
}
/* remove device node */
if (major(udev->devt) != 0 && strcmp(udev->action, "remove") == 0) {
struct name_entry *name_loop;
/* import and delete database entry */
if (udev_db_get_device(udev, udev->dev->devpath) == 0) {
udev_db_delete_device(udev);
if (udev->ignore_remove) {
dbg("remove event for '%s' requested to be ignored by rule", udev->name);
return 0;
}
/* restore stored persistent data */
list_for_each_entry(name_loop, &udev->env_list, node)
putenv(name_loop->name);
} else {
dbg("'%s' not found in database, using kernel name '%s'", udev->dev->devpath, udev->dev->kernel_name);
strlcpy(udev->name, udev->dev->kernel_name, sizeof(udev->name));
}
udev_rules_get_run(rules, udev);
if (udev->ignore_device) {
info("device event will be ignored");
goto exit;
}
retval = udev_node_remove(udev);
goto exit;
}
/* default devices */
udev_rules_get_run(rules, udev);
if (udev->ignore_device)
info("device event will be ignored");
exit:
return retval;
}