udev_db.c revision 1cec1c241600fc11121f9504bc9e95836c03bd9c
/*
* udev_db.c
*
* Userspace devfs
*
* Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2004 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 <string.h>
#include <stddef.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <dirent.h>
#include "libsysfs/sysfs/libsysfs.h"
#include "udev.h"
#include "udev_utils.h"
#include "logging.h"
#include "udev_db.h"
#define PATH_TO_NAME_CHAR '@'
static int get_db_filename(struct udevice *udev, char *filename, int len)
{
char devpath[SYSFS_PATH_MAX];
char *pos;
/* replace '/' to transform path into a filename */
strfieldcpy(devpath, udev->devpath);
pos = strchr(&devpath[1], '/');
while (pos) {
pos[0] = PATH_TO_NAME_CHAR;
pos = strchr(&pos[1], '/');
}
snprintf(filename, len, "%s%s", udev_db_path, devpath);
filename[len-1] = '\0';
return 0;
}
int udev_db_add_device(struct udevice *udev)
{
char filename[SYSFS_PATH_MAX];
FILE *f;
if (udev->test_run)
return 0;
get_db_filename(udev, filename, SYSFS_PATH_MAX);
create_path(filename);
f = fopen(filename, "w");
if (f == NULL) {
dbg("unable to create db file '%s'", filename);
return -1;
}
dbg("storing data for device '%s' in '%s'", udev->devpath, filename);
fprintf(f, "P:%s\n", udev->devpath);
fprintf(f, "N:%s\n", udev->name);
fprintf(f, "S:%s\n", udev->symlink);
fprintf(f, "M:%u:%u\n", udev->major, udev->minor);
fprintf(f, "A:%u\n", udev->partitions);
fprintf(f, "R:%u\n", udev->ignore_remove);
fclose(f);
return 0;
}
static int parse_db_file(struct udevice *udev, const char *filename)
{
char line[NAME_SIZE];
char temp[NAME_SIZE];
char *bufline;
char *buf;
size_t bufsize;
size_t cur;
size_t count;
if (file_map(filename, &buf, &bufsize) != 0) {
dbg("unable to read db file '%s'", filename);
return -1;
}
cur = 0;
while (cur < bufsize) {
count = buf_get_line(buf, bufsize, cur);
bufline = &buf[cur];
cur += count+1;
switch(bufline[0]) {
case 'P':
if (count > DEVPATH_SIZE)
count = DEVPATH_SIZE-1;
strncpy(udev->devpath, &bufline[2], count-2);
udev->devpath[count-2] = '\0';
break;
case 'N':
if (count > NAME_SIZE)
count = NAME_SIZE-1;
strncpy(udev->name, &bufline[2], count-2);
udev->name[count-2] = '\0';
break;
case 'M':
if (count > NAME_SIZE)
count = NAME_SIZE-1;
strncpy(temp, &bufline[2], count-2);
temp[count-2] = '\0';
sscanf(temp, "%u:%u", &udev->major, &udev->minor);
break;
case 'S':
if (count > NAME_SIZE)
count = NAME_SIZE-1;
strncpy(udev->symlink, &bufline[2], count-2);
udev->symlink[count-2] = '\0';
break;
case 'A':
if (count > NAME_SIZE)
count = NAME_SIZE-1;
strncpy(line, &bufline[2], count-2);
line[count-2] = '\0';
udev->partitions = atoi(line);
break;
case 'R':
if (count > NAME_SIZE)
count = NAME_SIZE-1;
strncpy(line, &bufline[2], count-2);
line[count-2] = '\0';
udev->ignore_remove = atoi(line);
break;
}
}
if (udev->name[0] == '\0')
return -1;
return 0;
}
int udev_db_get_device(struct udevice *udev)
{
char filename[SYSFS_PATH_MAX];
get_db_filename(udev, filename, SYSFS_PATH_MAX);
return parse_db_file(udev, filename);
}
int udev_db_delete_device(struct udevice *udev)
{
char filename[SYSFS_PATH_MAX];
get_db_filename(udev, filename, SYSFS_PATH_MAX);
unlink(filename);
return 0;
}
int udev_db_get_device_byname(struct udevice *udev, const char *name)
{
struct dirent *ent;
DIR *dir;
char filename[NAME_SIZE];
struct udevice db_udev;
dir = opendir(udev_db_path);
if (dir == NULL) {
dbg("unable to udev db '%s'", udev_db_path);
return -1;
}
while (1) {
ent = readdir(dir);
if (ent == NULL || ent->d_name[0] == '\0')
break;
if (ent->d_name[0] == '.')
continue;
snprintf(filename, NAME_SIZE, "%s/%s", udev_db_path, ent->d_name);
filename[NAME_SIZE-1] = '\0';
memset(&db_udev, 0x00, sizeof(struct udevice));
if (parse_db_file(&db_udev, filename) == 0) {
char *pos;
unsigned int len;
if (strncmp(name, db_udev.name, NAME_SIZE) == 0) {
goto found;
}
foreach_strpart(db_udev.symlink, " ", pos, len) {
if (strncmp(name, pos, len) != 0)
continue;
if (len == strlen(name))
goto found;
}
}
}
closedir(dir);
return -1;
found:
closedir(dir);
strfieldcpy(udev->devpath, db_udev.devpath);
strfieldcpy(udev->name, db_udev.name);
strfieldcpy(udev->symlink, db_udev.symlink);
udev->partitions = db_udev.partitions;
return 0;
}