Systemd/udev.c

185 lines
3.5 KiB
C

/*
* udev.c
*
* Userspace devfs
*
* Copyright (C) 2003,2004 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 <errno.h>
#include <ctype.h>
#include <signal.h>
#include "udev.h"
#include "udev_version.h"
#include "udev_dbus.h"
#include "logging.h"
#include "namedev.h"
#include "udevdb.h"
#include "libsysfs/libsysfs.h"
/* global variables */
char **main_argv;
char **main_envp;
unsigned char logname[42];
static void sig_handler(int signum)
{
dbg("caught signal %d", signum);
switch (signum) {
case SIGINT:
case SIGTERM:
sysbus_disconnect();
udevdb_exit();
exit(20 + signum);
break;
default:
dbg("unhandled signal");
}
}
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;
}
static char *subsystem_blacklist[] = {
"net",
"scsi_host",
"scsi_device",
"usb_host",
"pci_bus",
"",
};
static int udev_hotplug(int argc, char **argv)
{
char *action;
char *devpath;
char *subsystem;
int retval = -EINVAL;
int i;
action = get_action();
if (!action) {
dbg ("no action?");
goto exit;
}
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;
}
/* skip blacklisted subsystems */
subsystem = argv[1];
i = 0;
while (subsystem_blacklist[i][0] != '\0') {
if (strcmp(subsystem, subsystem_blacklist[i]) == 0) {
dbg("don't care about '%s' devices", subsystem);
goto exit;
}
i++;
}
/* connect to the system message bus */
sysbus_connect();
/* initialize our configuration */
udev_init_config();
/* initialize udev database */
retval = udevdb_init(UDEVDB_DEFAULT);
if (retval != 0) {
dbg("unable to initialize database");
goto exit_sysbus;
}
/* set up a default signal handler for now */
signal(SIGINT, sig_handler);
signal(SIGTERM, sig_handler);
/* 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();
exit_sysbus:
/* disconnect from the system message bus */
sysbus_disconnect();
exit:
if (retval > 0)
retval = 0;
return -retval;
}
int main(int argc, char **argv, char **envp)
{
main_argv = argv;
main_envp = envp;
init_logging("udev");
dbg("version %s", UDEV_VERSION);
return udev_hotplug(argc, argv);
}