udevstart.c revision 821d0ec803a72841f173739f5b713fe847edab75
/*
* udevstart.c
*
* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
*
* Quick and dirty way to populate a /dev with udev if your system
* does not have access to a shell. Based originally on a patch to udev
* from Harald Hoyer <harald@redhat.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 <stddef.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <ctype.h>
#include <dirent.h>
#include <signal.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/types.h>
#include "libsysfs/sysfs/libsysfs.h"
#include "udev_libc_wrapper.h"
#include "udev.h"
#include "udev_version.h"
#include "logging.h"
#include "udev_rules.h"
#include "udev_utils.h"
#include "list.h"
#ifdef USE_LOG
void log_message(int priority, const char *format, ...)
{
va_list args;
if (priority > udev_log_priority)
return;
va_start(args, format);
vsyslog(priority, format, args);
va_end(args);
}
#endif
struct device {
struct list_head node;
char path[PATH_SIZE];
char subsys[NAME_SIZE];
};
/* sort files in lexical order */
static int device_list_insert(const char *path, char *subsystem, struct list_head *device_list)
{
struct device *loop_device;
struct device *new_device;
dbg("insert: '%s'\n", path);
list_for_each_entry(loop_device, device_list, node) {
if (strcmp(loop_device->path, path) > 0) {
break;
}
}
new_device = malloc(sizeof(struct device));
if (new_device == NULL) {
dbg("error malloc");
return -ENOMEM;
}
strlcpy(new_device->path, path, sizeof(new_device->path));
strlcpy(new_device->subsys, subsystem, sizeof(new_device->subsys));
list_add_tail(&new_device->node, &loop_device->node);
dbg("add '%s' from subsys '%s'", new_device->path, new_device->subsys);
return 0;
}
/* list of devices that we should run last due to any one of a number of reasons */
static char *last_list[] = {
"/block/dm", /* on here because dm wants to have the block devices around before it */
NULL,
};
/* list of devices that we should run first due to any one of a number of reasons */
static char *first_list[] = {
"/class/mem", /* people tend to like their memory devices around first... */
NULL,
};
static int add_device(const char *path, const char *subsystem)
{
struct udevice udev;
struct sysfs_class_device *class_dev;
const char *devpath;
devpath = &path[strlen(sysfs_path)];
/* set environment for callouts and dev.d/ */
setenv("DEVPATH", devpath, 1);
setenv("SUBSYSTEM", subsystem, 1);
dbg("exec: '%s' (%s)\n", devpath, path);
class_dev = sysfs_open_class_device_path(path);
if (class_dev == NULL) {
dbg ("sysfs_open_class_device_path failed");
return -ENODEV;
}
udev_init_device(&udev, devpath, subsystem, "add");
udev_add_device(&udev, class_dev);
if (udev_run && !list_empty(&udev.run_list)) {
struct name_entry *name_loop;
dbg("executing run list");
list_for_each_entry(name_loop, &udev.run_list, node)
execute_command(name_loop->name, udev.subsystem);
}
/* run dev.d/ scripts if we created a node or changed a netif name */
if (udev_dev_d && udev.devname[0] != '\0') {
setenv("DEVNAME", udev.devname, 1);
udev_multiplex_directory(&udev, DEVD_DIR, DEVD_SUFFIX);
}
sysfs_close_class_device(class_dev);
udev_cleanup_device(&udev);
return 0;
}
static void exec_list(struct list_head *device_list)
{
struct device *loop_device;
struct device *tmp_device;
int i;
/* handle the "first" type devices first */
list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
for (i = 0; first_list[i] != NULL; i++) {
if (strncmp(loop_device->path, first_list[i], strlen(first_list[i])) == 0) {
add_device(loop_device->path, loop_device->subsys);
list_del(&loop_device->node);
free(loop_device);
break;
}
}
}
/* handle the devices we are allowed to, excluding the "last" type devices */
list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
int found = 0;
for (i = 0; last_list[i] != NULL; i++) {
if (strncmp(loop_device->path, last_list[i], strlen(last_list[i])) == 0) {
found = 1;
break;
}
}
if (found)
continue;
add_device(loop_device->path, loop_device->subsys);
list_del(&loop_device->node);
free(loop_device);
}
/* handle the rest of the devices left over, if any */
list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
add_device(loop_device->path, loop_device->subsys);
list_del(&loop_device->node);
free(loop_device);
}
}
static int has_devt(const char *directory)
{
char filename[PATH_SIZE];
struct stat statbuf;
snprintf(filename, sizeof(filename), "%s/dev", directory);
filename[sizeof(filename)-1] = '\0';
if (stat(filename, &statbuf) == 0)
return 1;
return 0;
}
static void udev_scan_block(void)
{
char base[PATH_SIZE];
DIR *dir;
struct dirent *dent;
LIST_HEAD(device_list);
snprintf(base, sizeof(base), "%s/block", sysfs_path);
base[sizeof(base)-1] = '\0';
dir = opendir(base);
if (dir != NULL) {
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char dirname[PATH_SIZE];
DIR *dir2;
struct dirent *dent2;
if (dent->d_name[0] == '.')
continue;
snprintf(dirname, sizeof(dirname), "%s/%s", base, dent->d_name);
dirname[sizeof(dirname)-1] = '\0';
if (has_devt(dirname))
device_list_insert(dirname, "block", &device_list);
else
continue;
/* look for partitions */
dir2 = opendir(dirname);
if (dir2 != NULL) {
for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
char dirname2[PATH_SIZE];
if (dent2->d_name[0] == '.')
continue;
snprintf(dirname2, sizeof(dirname2), "%s/%s", dirname, dent2->d_name);
dirname2[sizeof(dirname2)-1] = '\0';
if (has_devt(dirname2))
device_list_insert(dirname2, "block", &device_list);
}
closedir(dir2);
}
}
closedir(dir);
}
exec_list(&device_list);
}
static void udev_scan_class(void)
{
char base[PATH_SIZE];
DIR *dir;
struct dirent *dent;
LIST_HEAD(device_list);
snprintf(base, sizeof(base), "%s/class", sysfs_path);
base[sizeof(base)-1] = '\0';
dir = opendir(base);
if (dir != NULL) {
for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
char dirname[PATH_SIZE];
DIR *dir2;
struct dirent *dent2;
if (dent->d_name[0] == '.')
continue;
snprintf(dirname, sizeof(dirname), "%s/%s", base, dent->d_name);
dirname[sizeof(dirname)-1] = '\0';
dir2 = opendir(dirname);
if (dir2 != NULL) {
for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
char dirname2[PATH_SIZE];
if (dent2->d_name[0] == '.')
continue;
snprintf(dirname2, sizeof(dirname2), "%s/%s", dirname, dent2->d_name);
dirname2[sizeof(dirname2)-1] = '\0';
/* pass the net class as it is */
if (strcmp(dent->d_name, "net") == 0)
device_list_insert(dirname2, "net", &device_list);
else if (has_devt(dirname2))
device_list_insert(dirname2, dent->d_name, &device_list);
}
closedir(dir2);
}
}
closedir(dir);
}
exec_list(&device_list);
}
static void asmlinkage sig_handler(int signum)
{
switch (signum) {
case SIGALRM:
exit(1);
case SIGINT:
case SIGTERM:
exit(20 + signum);
}
}
int main(int argc, char *argv[], char *envp[])
{
struct sigaction act;
logging_init("udev");
udev_init_config();
/* disable all logging if not explicitely requested */
if (getenv("UDEV_LOG") == NULL)
udev_log_priority = 0;
dbg("version %s", UDEV_VERSION);
/* set signal handlers */
memset(&act, 0x00, sizeof(act));
act.sa_handler = (void (*) (int))sig_handler;
sigemptyset (&act.sa_mask);
act.sa_flags = 0;
sigaction(SIGALRM, &act, NULL);
sigaction(SIGINT, &act, NULL);
sigaction(SIGTERM, &act, NULL);
/* trigger timeout to prevent hanging processes */
alarm(ALARM_TIMEOUT);
/* set environment for executed programs */
setenv("ACTION", "add", 1);
setenv("UDEV_START", "1", 1);
udev_rules_init();
udev_scan_block();
udev_scan_class();
logging_close();
return 0;
}