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