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/*
* udev.c
*
* Userspace devfs
*
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
*
*
* 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 <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <ctype.h>
#include "udev.h"
#include "udev_version.h"
#include "namedev.h"
#include "udevdb.h"
#include "libsysfs/libsysfs.h"
/* global variables */
char **main_argv;
char **main_envp;
static inline char *get_action(void)
{
char *action;
action = getenv("ACTION");
return action;
}
static inline char *get_devpath(void)
{
char *devpath;
devpath = getenv("DEVPATH");
return devpath;
}
static inline char *get_seqnum(void)
{
char *seqnum;
seqnum = getenv("SEQNUM");
return seqnum;
}
#ifdef USE_DBUS
/** Global variable for the connection the to system message bus or #NULL
* if we cannot connect or acquire the org.kernel.udev service
*/
DBusConnection* sysbus_connection;
/** Disconnect from the system message bus */
static void sysbus_disconnect()
{
if (sysbus_connection == NULL)
return;
dbus_connection_disconnect(sysbus_connection);
sysbus_connection = NULL;
}
/** Connect to the system message bus */
static void sysbus_connect()
{
DBusError error;
/* Connect to a well-known bus instance, the system bus */
dbus_error_init(&error);
sysbus_connection = dbus_bus_get(DBUS_BUS_SYSTEM, &error);
if (sysbus_connection == NULL) {
dbg("cannot connect to system message bus, error %s: %s",
error.name, error.message);
dbus_error_free(&error);
return;
}
/* Acquire the org.kernel.udev service such that listeners
* know that the message is really from us and not from a
* random attacker. See the file udev_sysbus_policy.conf for
* details.
*
* Note that a service can have multiple owners (though there
* is a concept of a primary owner for reception of messages)
* so no race is introduced if two copies of udev is running
* at the same time.
*/
dbus_bus_acquire_service(sysbus_connection, "org.kernel.udev", 0,
&error);
if (dbus_error_is_set(&error)) {
printf("cannot acquire org.kernel.udev service, error %s: %s'",
error.name, error.message);
sysbus_disconnect();
return;
}
}
#endif /* USE_DBUS */
int main(int argc, char **argv, char **envp)
{
char *action;
char *devpath;
char *subsystem;
int retval = -EINVAL;
main_argv = argv;
main_envp = envp;
dbg("version %s", UDEV_VERSION);
if (argc != 2) {
dbg ("unknown number of arguments");
goto exit;
}
subsystem = argv[1];
devpath = get_devpath();
if (!devpath) {
dbg ("no devpath?");
goto exit;
}
dbg("looking at '%s'", devpath);
/* we only care about class devices and block stuff */
if (!strstr(devpath, "class") &&
!strstr(devpath, "block")) {
dbg("not a block or class device");
goto exit;
}
/* but we don't care about net class devices */
if (strcmp(subsystem, "net") == 0) {
dbg("don't care about net devices");
goto exit;
}
action = get_action();
if (!action) {
dbg ("no action?");
goto exit;
}
/* initialize our configuration */
udev_init_config();
#ifdef USE_DBUS
/* connect to the system message bus */
sysbus_connect();
#endif /* USE_DBUS */
/* initialize udev database */
retval = udevdb_init(UDEVDB_DEFAULT);
if (retval != 0) {
dbg("unable to initialize database");
goto exit;
}
/* initialize the naming deamon */
namedev_init();
if (strcmp(action, "add") == 0)
retval = udev_add_device(devpath, subsystem);
else if (strcmp(action, "remove") == 0)
retval = udev_remove_device(devpath, subsystem);
else {
dbg("unknown action '%s'", action);
retval = -EINVAL;
}
udevdb_exit();
#ifdef USE_DBUS
/* disconnect from the system message bus */
sysbus_disconnect();
#endif /* USE_DBUS */
exit:
return retval;
}
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