udev_db.c

   1 /*
   2  * udev_db.c
   3  *
   4  * Userspace devfs
   5  *
   6  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
   7  * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
   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
  25 #include <stdlib.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <stddef.h>
  29 #include <fcntl.h>
  30 #include <string.h>
  31 #include <errno.h>
  32 #include <dirent.h>
  33
  34 #include "libsysfs/sysfs/libsysfs.h"
  35 #include "udev.h"
  36 #include "udev_utils.h"
  37 #include "logging.h"
  38 #include "udev_db.h"
  39
  40 #define PATH_TO_NAME_CHAR               '@'
  41
  42 static int get_db_filename(const char *devpath, char *filename, int len)
  43 {
  44         char temp[SYSFS_PATH_MAX];
  45         char *pos;
  46
  47         /* replace '/' to transform path into a filename */
  48         strfieldcpy(temp, devpath);
  49         pos = strchr(&temp[1], '/');
  50         while (pos) {
  51                 pos[0] = PATH_TO_NAME_CHAR;
  52                 pos = strchr(&pos[1], '/');
  53         }
  54         snprintf(filename, len, "%s%s", udev_db_path, temp);
  55         filename[len-1] = '\0';
  56
  57         return 0;
  58 }
  59
  60 int udev_db_add_device(struct udevice *udev)
  61 {
  62         char filename[SYSFS_PATH_MAX];
  63         struct name_entry *name_loop;
  64         FILE *f;
  65
  66         if (udev->test_run)
  67                 return 0;
  68
  69         get_db_filename(udev->devpath, filename, SYSFS_PATH_MAX);
  70
  71         create_path(filename);
  72
  73         f = fopen(filename, "w");
  74         if (f == NULL) {
  75                 dbg("unable to create db file '%s'", filename);
  76                 return -1;
  77         }
  78         dbg("storing data for device '%s' in '%s'", udev->devpath, filename);
  79
  80         fprintf(f, "P:%s\n", udev->devpath);
  81         fprintf(f, "N:%s\n", udev->name);
  82         list_for_each_entry(name_loop, &udev->symlink_list, node)
  83                 fprintf(f, "S:%s\n", name_loop->name);
  84         fprintf(f, "M:%u:%u\n", major(udev->devt), minor(udev->devt));
  85         fprintf(f, "A:%u\n", udev->partitions);
  86         fprintf(f, "R:%u\n", udev->ignore_remove);
  87
  88         fclose(f);
  89
  90         return 0;
  91 }
  92
  93 static int parse_db_file(struct udevice *udev, const char *filename)
  94 {
  95         char line[NAME_SIZE];
  96         char temp[NAME_SIZE];
  97         unsigned int major, minor;
  98         char *bufline;
  99         char *buf;
 100         size_t bufsize;
 101         size_t cur;
 102         size_t count;
 103
 104         if (file_map(filename, &buf, &bufsize) != 0) {
 105                 dbg("unable to read db file '%s'", filename);
 106                 return -1;
 107         }
 108
 109         cur = 0;
 110         while (cur < bufsize) {
 111                 count = buf_get_line(buf, bufsize, cur);
 112                 bufline = &buf[cur];
 113                 cur += count+1;
 114
 115                 switch(bufline[0]) {
 116                 case 'P':
 117                         if (count > DEVPATH_SIZE)
 118                                 count = DEVPATH_SIZE-1;
 119                         strncpy(udev->devpath, &bufline[2], count-2);
 120                         udev->devpath[count-2] = '\0';
 121                         break;
 122                 case 'N':
 123                         if (count > NAME_SIZE)
 124                                 count = NAME_SIZE-1;
 125                         strncpy(udev->name, &bufline[2], count-2);
 126                         udev->name[count-2] = '\0';
 127                         break;
 128                 case 'M':
 129                         if (count > NAME_SIZE)
 130                                 count = NAME_SIZE-1;
 131                         strncpy(temp, &bufline[2], count-2);
 132                         temp[count-2] = '\0';
 133                         sscanf(temp, "%u:%u", &major, &minor);
 134                         udev->devt = makedev(major, minor);
 135                         break;
 136                 case 'S':
 137                         if (count > NAME_SIZE)
 138                                 count = NAME_SIZE-1;
 139                         strncpy(temp, &bufline[2], count-2);
 140                         temp[count-2] = '\0';
 141                         name_list_add(&udev->symlink_list, temp, 0);
 142                         break;
 143                 case 'A':
 144                         if (count > NAME_SIZE)
 145                                 count = NAME_SIZE-1;
 146                         strncpy(line, &bufline[2], count-2);
 147                         line[count-2] = '\0';
 148                         udev->partitions = atoi(line);
 149                         break;
 150                 case 'R':
 151                         if (count > NAME_SIZE)
 152                                 count = NAME_SIZE-1;
 153                         strncpy(line, &bufline[2], count-2);
 154                         line[count-2] = '\0';
 155                         udev->ignore_remove = atoi(line);
 156                         break;
 157                 }
 158         }
 159         file_unmap(buf, bufsize);
 160
 161         if (udev->name[0] == '\0')
 162                 return -1;
 163
 164         return 0;
 165 }
 166
 167 int udev_db_delete_device(struct udevice *udev)
 168 {
 169         char filename[SYSFS_PATH_MAX];
 170
 171         get_db_filename(udev->devpath, filename, SYSFS_PATH_MAX);
 172         unlink(filename);
 173
 174         return 0;
 175 }
 176
 177 int udev_db_get_device(struct udevice *udev, const char *devpath)
 178 {
 179         char filename[SYSFS_PATH_MAX];
 180
 181         get_db_filename(devpath, filename, SYSFS_PATH_MAX);
 182
 183         if (parse_db_file(udev, filename) != 0)
 184                 return -1;
 185
 186         return 0;
 187 }
 188
 189 int udev_db_search_name(char *devpath, size_t len, const char *name)
 190 {
 191         struct dirent *ent;
 192         DIR *dir;
 193         char filename[NAME_SIZE];
 194
 195         dir = opendir(udev_db_path);
 196         if (dir == NULL) {
 197                 dbg("unable to udev db '%s'", udev_db_path);
 198                 return -1;
 199         }
 200
 201         while (1) {
 202                 char path[DEVPATH_SIZE];
 203                 char nodename[NAME_SIZE];
 204                 char *bufline;
 205                 char *buf;
 206                 size_t bufsize;
 207                 size_t cur;
 208                 size_t count;
 209
 210                 ent = readdir(dir);
 211                 if (ent == NULL || ent->d_name[0] == '\0')
 212                         break;
 213
 214                 if (ent->d_name[0] == '.')
 215                         continue;
 216
 217                 snprintf(filename, NAME_SIZE, "%s/%s", udev_db_path, ent->d_name);
 218                 filename[NAME_SIZE-1] = '\0';
 219                 dbg("looking at '%s'", filename);
 220
 221                 if (file_map(filename, &buf, &bufsize) != 0) {
 222                         dbg("unable to read db file '%s'", filename);
 223                         continue;
 224                 }
 225
 226                 cur = 0;
 227                 while (cur < bufsize) {
 228                         count = buf_get_line(buf, bufsize, cur);
 229                         bufline = &buf[cur];
 230                         cur += count+1;
 231
 232                         switch(bufline[0]) {
 233                         case 'P':
 234                                 if (count > DEVPATH_SIZE)
 235                                         count = DEVPATH_SIZE-1;
 236                                 strncpy(path, &bufline[2], count-2);
 237                                 path[count-2] = '\0';
 238                                 break;
 239                         case 'N':
 240                         case 'S':
 241                                 if (count > NAME_SIZE)
 242                                 count = NAME_SIZE-1;
 243                                 strncpy(nodename, &bufline[2], count-2);
 244                                 nodename[count-2] = '\0';
 245                                 dbg("compare '%s' '%s'", nodename, name);
 246                                 if (strcmp(nodename, name) == 0) {
 247                                         strncpy(devpath, path, len);
 248                                         devpath[len] = '\0';
 249                                         file_unmap(buf, bufsize);
 250                                         closedir(dir);
 251                                         return 0;
 252                                 }
 253                                 break;
 254                         default:
 255                                 continue;
 256                         }
 257                 }
 258                 file_unmap(buf, bufsize);
 259         }
 260
 261         closedir(dir);
 262         return -1;
 263 }
 264
 265 int udev_db_call_foreach(int (*handler_function)(struct udevice *udev))
 266 {
 267         struct dirent *ent;
 268         DIR *dir;
 269         char filename[NAME_SIZE];
 270         struct udevice db_udev;
 271
 272         dir = opendir(udev_db_path);
 273         if (dir == NULL) {
 274                 dbg("unable to udev db '%s'", udev_db_path);
 275                 return -1;
 276         }
 277
 278         while (1) {
 279                 ent = readdir(dir);
 280                 if (ent == NULL || ent->d_name[0] == '\0')
 281                         break;
 282
 283                 if (ent->d_name[0] == '.')
 284                         continue;
 285
 286                 snprintf(filename, NAME_SIZE, "%s/%s", udev_db_path, ent->d_name);
 287                 filename[NAME_SIZE-1] = '\0';
 288
 289                 dbg("found '%s'", filename);
 290
 291                 udev_init_device(&db_udev, NULL, NULL);
 292                 if (parse_db_file(&db_udev, filename) == 0) {
 293                         if (handler_function(&db_udev) != 0)
 294                                 break;
 295                 }
 296         }
 297
 298         closedir(dir);
 299         return 0;
 300 }