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 <unistd.h>
  30 #include <fcntl.h>
  31 #include <string.h>
  32 #include <errno.h>
  33 #include <dirent.h>
  34
  35 #include "libsysfs/sysfs/libsysfs.h"
  36 #include "udev.h"
  37 #include "udev_utils.h"
  38 #include "logging.h"
  39 #include "udev_db.h"
  40
  41 #define PATH_TO_NAME_CHAR               '@'
  42
  43 static int get_db_filename(const char *devpath, char *filename, int len)
  44 {
  45         char temp[SYSFS_PATH_MAX];
  46         char *pos;
  47
  48         /* replace '/' to transform path into a filename */
  49         strfieldcpy(temp, devpath);
  50         pos = strchr(&temp[1], '/');
  51         while (pos) {
  52                 pos[0] = PATH_TO_NAME_CHAR;
  53                 pos = strchr(&pos[1], '/');
  54         }
  55         snprintf(filename, len, "%s%s", udev_db_path, temp);
  56         filename[len-1] = '\0';
  57
  58         return 0;
  59 }
  60
  61 int udev_db_add_device(struct udevice *udev)
  62 {
  63         char filename[SYSFS_PATH_MAX];
  64         struct name_entry *name_loop;
  65         FILE *f;
  66
  67         if (udev->test_run)
  68                 return 0;
  69
  70         get_db_filename(udev->devpath, filename, SYSFS_PATH_MAX);
  71
  72         create_path(filename);
  73
  74         f = fopen(filename, "w");
  75         if (f == NULL) {
  76                 dbg("unable to create db file '%s'", filename);
  77                 return -1;
  78         }
  79         dbg("storing data for device '%s' in '%s'", udev->devpath, filename);
  80
  81         fprintf(f, "P:%s\n", udev->devpath);
  82         fprintf(f, "N:%s\n", udev->name);
  83         list_for_each_entry(name_loop, &udev->symlink_list, node)
  84                 fprintf(f, "S:%s\n", name_loop->name);
  85         fprintf(f, "M:%u:%u\n", major(udev->devt), minor(udev->devt));
  86         fprintf(f, "A:%u\n", udev->partitions);
  87         fprintf(f, "R:%u\n", udev->ignore_remove);
  88
  89         fclose(f);
  90
  91         return 0;
  92 }
  93
  94 static int parse_db_file(struct udevice *udev, const char *filename)
  95 {
  96         char line[NAME_SIZE];
  97         char temp[NAME_SIZE];
  98         unsigned int major, minor;
  99         char *bufline;
 100         char *buf;
 101         size_t bufsize;
 102         size_t cur;
 103         size_t count;
 104
 105         if (file_map(filename, &buf, &bufsize) != 0) {
 106                 dbg("unable to read db file '%s'", filename);
 107                 return -1;
 108         }
 109
 110         cur = 0;
 111         while (cur < bufsize) {
 112                 count = buf_get_line(buf, bufsize, cur);
 113                 bufline = &buf[cur];
 114                 cur += count+1;
 115
 116                 switch(bufline[0]) {
 117                 case 'P':
 118                         if (count > DEVPATH_SIZE)
 119                                 count = DEVPATH_SIZE-1;
 120                         strncpy(udev->devpath, &bufline[2], count-2);
 121                         udev->devpath[count-2] = '\0';
 122                         break;
 123                 case 'N':
 124                         if (count > NAME_SIZE)
 125                                 count = NAME_SIZE-1;
 126                         strncpy(udev->name, &bufline[2], count-2);
 127                         udev->name[count-2] = '\0';
 128                         break;
 129                 case 'M':
 130                         if (count > NAME_SIZE)
 131                                 count = NAME_SIZE-1;
 132                         strncpy(temp, &bufline[2], count-2);
 133                         temp[count-2] = '\0';
 134                         sscanf(temp, "%u:%u", &major, &minor);
 135                         udev->devt = makedev(major, minor);
 136                         break;
 137                 case 'S':
 138                         if (count > NAME_SIZE)
 139                                 count = NAME_SIZE-1;
 140                         strncpy(temp, &bufline[2], count-2);
 141                         temp[count-2] = '\0';
 142                         name_list_add(&udev->symlink_list, temp, 0);
 143                         break;
 144                 case 'A':
 145                         if (count > NAME_SIZE)
 146                                 count = NAME_SIZE-1;
 147                         strncpy(line, &bufline[2], count-2);
 148                         line[count-2] = '\0';
 149                         udev->partitions = atoi(line);
 150                         break;
 151                 case 'R':
 152                         if (count > NAME_SIZE)
 153                                 count = NAME_SIZE-1;
 154                         strncpy(line, &bufline[2], count-2);
 155                         line[count-2] = '\0';
 156                         udev->ignore_remove = atoi(line);
 157                         break;
 158                 }
 159         }
 160         file_unmap(buf, bufsize);
 161
 162         if (udev->name[0] == '\0')
 163                 return -1;
 164
 165         return 0;
 166 }
 167
 168 int udev_db_delete_device(struct udevice *udev)
 169 {
 170         char filename[SYSFS_PATH_MAX];
 171
 172         get_db_filename(udev->devpath, filename, SYSFS_PATH_MAX);
 173         unlink(filename);
 174
 175         return 0;
 176 }
 177
 178 int udev_db_get_device(struct udevice *udev, const char *devpath)
 179 {
 180         char filename[SYSFS_PATH_MAX];
 181
 182         get_db_filename(devpath, filename, SYSFS_PATH_MAX);
 183
 184         if (parse_db_file(udev, filename) != 0)
 185                 return -1;
 186
 187         return 0;
 188 }
 189
 190 int udev_db_search_name(char *devpath, size_t len, const char *name)
 191 {
 192         DIR *dir;
 193
 194         dir = opendir(udev_db_path);
 195         if (dir == NULL) {
 196                 dbg("unable to udev db '%s'", udev_db_path);
 197                 return -1;
 198         }
 199
 200         while (1) {
 201                 struct dirent *ent;
 202                 char filename[NAME_SIZE];
 203                 char path[DEVPATH_SIZE];
 204                 char nodename[NAME_SIZE];
 205                 char *bufline;
 206                 char *buf;
 207                 size_t bufsize;
 208                 size_t cur;
 209                 size_t count;
 210
 211                 ent = readdir(dir);
 212                 if (ent == NULL || ent->d_name[0] == '\0')
 213                         break;
 214
 215                 if (ent->d_name[0] == '.')
 216                         continue;
 217
 218                 snprintf(filename, NAME_SIZE, "%s/%s", udev_db_path, ent->d_name);
 219                 filename[NAME_SIZE-1] = '\0';
 220                 dbg("looking at '%s'", filename);
 221
 222                 if (file_map(filename, &buf, &bufsize) != 0) {
 223                         dbg("unable to read db file '%s'", filename);
 224                         continue;
 225                 }
 226
 227                 cur = 0;
 228                 while (cur < bufsize) {
 229                         count = buf_get_line(buf, bufsize, cur);
 230                         bufline = &buf[cur];
 231                         cur += count+1;
 232
 233                         switch(bufline[0]) {
 234                         case 'P':
 235                                 if (count > DEVPATH_SIZE)
 236                                         count = DEVPATH_SIZE-1;
 237                                 strncpy(path, &bufline[2], count-2);
 238                                 path[count-2] = '\0';
 239                                 break;
 240                         case 'N':
 241                         case 'S':
 242                                 if (count > NAME_SIZE)
 243                                 count = NAME_SIZE-1;
 244                                 strncpy(nodename, &bufline[2], count-2);
 245                                 nodename[count-2] = '\0';
 246                                 dbg("compare '%s' '%s'", nodename, name);
 247                                 if (strcmp(nodename, name) == 0) {
 248                                         strncpy(devpath, path, len);
 249                                         devpath[len] = '\0';
 250                                         file_unmap(buf, bufsize);
 251                                         closedir(dir);
 252                                         return 0;
 253                                 }
 254                                 break;
 255                         default:
 256                                 continue;
 257                         }
 258                 }
 259                 file_unmap(buf, bufsize);
 260         }
 261
 262         closedir(dir);
 263         return -1;
 264 }
 265
 266 int udev_db_dump_names(int (*handler_function)(const char *path, const char *name))
 267 {
 268         DIR *dir;
 269
 270         dir = opendir(udev_db_path);
 271         if (dir == NULL) {
 272                 dbg("unable to udev db '%s'", udev_db_path);
 273                 return -1;
 274         }
 275
 276         while (1) {
 277                 struct dirent *ent;
 278                 char filename[NAME_SIZE];
 279                 char path[DEVPATH_SIZE];
 280                 char nodename[NAME_SIZE];
 281                 char *bufline;
 282                 char *buf;
 283                 size_t bufsize;
 284                 size_t cur;
 285                 size_t count;
 286
 287                 ent = readdir(dir);
 288                 if (ent == NULL || ent->d_name[0] == '\0')
 289                         break;
 290
 291                 if (ent->d_name[0] == '.')
 292                         continue;
 293
 294                 snprintf(filename, NAME_SIZE, "%s/%s", udev_db_path, ent->d_name);
 295                 filename[NAME_SIZE-1] = '\0';
 296                 dbg("looking at '%s'", filename);
 297
 298                 if (file_map(filename, &buf, &bufsize) != 0) {
 299                         dbg("unable to read db file '%s'", filename);
 300                         continue;
 301                 }
 302
 303                 path[0] = '\0';
 304                 nodename[0] = '\0';
 305                 cur = 0;
 306                 while (cur < bufsize) {
 307                         count = buf_get_line(buf, bufsize, cur);
 308                         bufline = &buf[cur];
 309                         cur += count+1;
 310
 311                         switch(bufline[0]) {
 312                         case 'P':
 313                                 if (count > DEVPATH_SIZE)
 314                                         count = DEVPATH_SIZE-1;
 315                                 strncpy(path, &bufline[2], count-2);
 316                                 path[count-2] = '\0';
 317                                 break;
 318                         case 'N':
 319                                 if (count > NAME_SIZE)
 320                                 count = NAME_SIZE-1;
 321                                 strncpy(nodename, &bufline[2], count-2);
 322                                 nodename[count-2] = '\0';
 323                                 break;
 324                         default:
 325                                 continue;
 326                         }
 327                 }
 328                 file_unmap(buf, bufsize);
 329
 330                 if (path[0] == '\0' || nodename[0] == '\0')
 331                         continue;
 332
 333                 if (handler_function(path, nodename) != 0)
 334                         break;
 335         }
 336
 337         closedir(dir);
 338         return 0;
 339 }