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.h"
  34 #include "udev_utils.h"
  35 #include "udev_version.h"
  36 #include "namedev.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[NAME_SIZE];
  73         char partitionname[NAME_SIZE];
  74         int retval;
  75         int i;
  76         char *pos;
  77         int len;
  78         int num;
  79
  80         snprintf(filename, NAME_SIZE, "%s/%s", udev_root, udev->name);
  81         filename[NAME_SIZE-1] = '\0';
  82
  83         info("removing device node '%s'", filename);
  84         retval = unlink_secure(filename);
  85         if (retval)
  86                 return retval;
  87
  88         /* remove all_partitions nodes */
  89         num = udev->partitions;
  90         if (num > 0) {
  91                 info("removing all_partitions '%s[1-%i]'", filename, num);
  92                 if (num > PARTITIONS_COUNT) {
  93                         info("garbage from udev database, skip all_partitions removal");
  94                         return -1;
  95                 }
  96                 for (i = 1; i <= num; i++) {
  97                         strfieldcpy(partitionname, filename);
  98                         strintcat(partitionname, i);
  99                         unlink_secure(partitionname);
 100                 }
 101         }
 102
 103         /* remove subdirectories */
 104         if (strchr(udev->name, '/'))
 105                 delete_path(filename);
 106
 107         foreach_strpart(udev->symlink, " ", pos, len) {
 108                 char linkname[NAME_SIZE];
 109
 110                 strfieldcpymax(linkname, pos, len+1);
 111                 snprintf(filename, NAME_SIZE, "%s/%s", udev_root, linkname);
 112                 filename[NAME_SIZE-1] = '\0';
 113
 114                 dbg("unlinking symlink '%s'", filename);
 115                 retval = unlink(filename);
 116                 if (errno == ENOENT)
 117                         retval = 0;
 118                 if (retval) {
 119                         dbg("unlink(%s) failed with error '%s'",
 120                                 filename, strerror(errno));
 121                         return retval;
 122                 }
 123                 if (strchr(udev->symlink, '/')) {
 124                         delete_path(filename);
 125                 }
 126         }
 127
 128         return retval;
 129 }
 130
 131 /*
 132  * look up the sysfs path in the database to get the node name to remove
 133  * If we can't find it, use kernel name for lack of anything else to know to do
 134  */
 135 int udev_remove_device(struct udevice *udev)
 136 {
 137         const char *temp;
 138         int retval;
 139
 140         if (udev->type != 'b' && udev->type != 'c')
 141                 return 0;
 142
 143         retval = udev_db_get_device(udev);
 144         if (retval) {
 145                 /* fall back to kernel name */
 146                 temp = strrchr(udev->devpath, '/');
 147                 if (temp == NULL)
 148                         return -ENODEV;
 149                 strfieldcpy(udev->name, &temp[1]);
 150                 dbg("'%s' not found in database, falling back on default name", udev->name);
 151         }
 152
 153         if (udev->ignore_remove) {
 154                 dbg("remove event for '%s' requested to be ignored by rule", udev->name);
 155                 return 0;
 156         }
 157
 158         dbg("remove name='%s'", udev->name);
 159         udev_db_delete_device(udev);
 160
 161         /* use full path to the environment */
 162         snprintf(udev->devname, NAME_SIZE, "%s/%s", udev_root, udev->name);
 163
 164         return delete_node(udev);
 165 }