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 <stdio.h>
  27 #include <fcntl.h>
  28 #include <unistd.h>
  29 #include <errno.h>
  30
  31 #include "udev.h"
  32 #include "udev_version.h"
  33 #include "namedev.h"
  34 #include "udevdb.h"
  35 #include "libsysfs/libsysfs.h"
  36
  37
  38 /*
  39  * Look up the sysfs path in the database to see if we have named this device
  40  * something different from the kernel name.  If we have, us it.  If not, use
  41  * the default kernel name for lack of anything else to know to do.
  42  */
  43 static char *get_name(char *path, int major, int minor)
  44 {
  45         static char name[100];
  46         struct udevice *dev;
  47         char *temp;
  48
  49         dev = udevdb_get_dev(path);
  50         if (dev != NULL) {
  51                 strcpy(name, dev->name);
  52                 goto exit;
  53         }
  54
  55         dbg("'%s' not found in database, falling back on default name", path);
  56         temp = strrchr(path, '/');
  57         if (temp == NULL)
  58                 return NULL;
  59         strncpy(name, &temp[1], sizeof(name));
  60
  61 exit:
  62         dbg("name is '%s'", name);
  63         return &name[0];
  64 }
  65
  66 /*
  67  * We also want to clean up any symlinks that were created in create_node()
  68  */
  69 static int delete_node(char *name)
  70 {
  71         char filename[255];
  72         int retval;
  73
  74         strncpy(filename, udev_root, sizeof(filename));
  75         strncat(filename, name, sizeof(filename));
  76
  77         dbg("unlinking '%s'", filename);
  78         retval = unlink(filename);
  79         if (retval) {
  80                 dbg("unlink(%s) failed with error '%s'",
  81                         filename, strerror(errno));
  82                 return retval;
  83         }
  84
  85         /* remove subdirectories */
  86         if (strchr(name, '/')) {
  87                 char *pos;
  88
  89                 pos = strrchr(filename, '/');
  90                 while (1) {
  91                         *pos = 0x00;
  92                         pos = strrchr(filename, '/');
  93
  94                         /* don't remove the last one */
  95                         if ((pos == filename) || (pos == NULL))
  96                                 break;
  97
  98                         /* remove if empty */
  99                         retval = rmdir(filename);
 100                         if (retval) {
 101                                 if (errno == ENOTEMPTY)
 102                                         return 0;
 103                                 dbg("rmdir(%s) failed with error '%s'",
 104                                     filename, strerror(errno));
 105                                 break;
 106                         }
 107                         dbg("removed '%s'", filename);
 108                 }
 109         }
 110         return retval;
 111 }
 112
 113 int udev_remove_device(char *device, char *subsystem)
 114 {
 115         char *name;
 116         int retval = 0;
 117
 118         name = get_name(device, 0, 0);
 119         if (name == NULL) {
 120                 dbg ("get_name failed");
 121                 retval = -ENODEV;
 122                 goto exit;
 123         }
 124
 125         udevdb_delete_dev(device);
 126
 127         return delete_node(name);
 128
 129 exit:
 130         return retval;
 131 }