udev_remove.c

   1 /*
   2  * udev-remove.c
   3  *
   4  * Userspace devfs
   5  *
   6  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
   7  *
   8  *
   9  *      This program is free software; you can redistribute it and/or modify it
  10  *      under the terms of the GNU General Public License as published by the
  11  *      Free Software Foundation version 2 of the License.
  12  *
  13  *      This program is distributed in the hope that it will be useful, but
  14  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *      General Public License for more details.
  17  *
  18  *      You should have received a copy of the GNU General Public License along
  19  *      with this program; if not, write to the Free Software Foundation, Inc.,
  20  *      675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  */
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <stddef.h>
  27 #include <stdio.h>
  28 #include <fcntl.h>
  29 #include <unistd.h>
  30 #include <errno.h>
  31 #include <sys/stat.h>
  32
  33 #include "udev_libc_wrapper.h"
  34 #include "udev.h"
  35 #include "udev_utils.h"
  36 #include "udev_version.h"
  37 #include "udev_db.h"
  38 #include "logging.h"
  39
  40 static int delete_path(const char *path)
  41 {
  42         char *pos;
  43         int retval;
  44
  45         pos = strrchr(path, '/');
  46         while (1) {
  47                 *pos = '\0';
  48                 pos = strrchr(path, '/');
  49
  50                 /* don't remove the last one */
  51                 if ((pos == path) || (pos == NULL))
  52                         break;
  53
  54                 /* remove if empty */
  55                 retval = rmdir(path);
  56                 if (errno == ENOENT)
  57                         retval = 0;
  58                 if (retval) {
  59                         if (errno == ENOTEMPTY)
  60                                 return 0;
  61                         dbg("rmdir(%s) failed with error '%s'",
  62                             path, strerror(errno));
  63                         break;
  64                 }
  65                 dbg("removed '%s'", path);
  66         }
  67         return 0;
  68 }
  69
  70 static int delete_node(struct udevice *udev)
  71 {
  72         char filename[PATH_SIZE];
  73         char partitionname[PATH_SIZE];
  74         struct name_entry *name_loop;
  75         struct stat stats;
  76         int retval;
  77         int i;
  78         int num;
  79
  80         list_for_each_entry(name_loop, &udev->symlink_list, node) {
  81                 snprintf(filename, sizeof(filename), "%s/%s", udev_root, name_loop->name);
  82                 filename[sizeof(filename)-1] = '\0';
  83
  84                 if (stat(filename, &stats) != 0) {
  85                         dbg("symlink '%s' not found", filename);
  86                         continue;
  87                 }
  88                 if (udev->devt && stats.st_rdev != udev->devt) {
  89                         info("symlink '%s' points to a different device, skip removal", filename);
  90                         continue;;
  91                 }
  92
  93                 dbg("removing symlink '%s'", filename);
  94                 unlink(filename);
  95
  96                 if (strchr(filename, '/'))
  97                         delete_path(filename);
  98         }
  99
 100         snprintf(filename, sizeof(filename), "%s/%s", udev_root, udev->name);
 101         filename[sizeof(filename)-1] = '\0';
 102
 103         if (stat(filename, &stats) != 0) {
 104                 dbg("device node '%s' not found", filename);
 105                 return -1;
 106         }
 107         if (udev->devt && stats.st_rdev != udev->devt) {
 108                 info("device node '%s' points to a different device, skip removal", filename);
 109                 return -1;
 110         }
 111
 112         info("removing device node '%s'", filename);
 113         retval = unlink_secure(filename);
 114         if (retval)
 115                 return retval;
 116
 117         num = udev->partitions;
 118         if (num > 0) {
 119                 info("removing all_partitions '%s[1-%i]'", filename, num);
 120                 if (num > 255) {
 121                         info("garbage from udev database, skip all_partitions removal");
 122                         return -1;
 123                 }
 124                 for (i = 1; i <= num; i++) {
 125                         snprintf(partitionname, sizeof(partitionname), "%s%d", filename, i);
 126                         partitionname[sizeof(partitionname)-1] = '\0';
 127                         unlink_secure(partitionname);
 128                 }
 129         }
 130
 131         if (strchr(udev->name, '/'))
 132                 delete_path(filename);
 133
 134         return retval;
 135 }
 136
 137 /*
 138  * look up the sysfs path in the database to get the node name to remove
 139  * If we can't find it, use kernel name for lack of anything else to know to do
 140  */
 141 int udev_remove_device(struct udevice *udev)
 142 {
 143         if (udev->type != DEV_BLOCK && udev->type != DEV_CLASS)
 144                 return 0;
 145
 146         if (udev_db_get_device(udev, udev->devpath) == 0) {
 147                 if (udev->ignore_remove) {
 148                         dbg("remove event for '%s' requested to be ignored by rule", udev->name);
 149                         return 0;
 150                 }
 151                 dbg("remove name='%s'", udev->name);
 152                 udev_db_delete_device(udev);
 153         } else {
 154                 dbg("'%s' not found in database, using kernel name '%s'", udev->devpath, udev->kernel_name);
 155                 strlcpy(udev->name, udev->kernel_name, sizeof(udev->name));
 156         }
 157         /* use full path to the environment */
 158         snprintf(udev->devname, sizeof(udev->devname), "%s/%s", udev_root, udev->name);
 159         udev->devname[sizeof(udev->devname)-1] = '\0';
 160
 161         return delete_node(udev);
 162 }