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
  90         fclose(f);
  91
  92         return 0;
  93 }
  94
  95 static int parse_db_file(struct udevice *udev, const char *filename)
  96 {
  97         char line[PATH_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                 err("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 > sizeof(udev->devpath))
 119                                 count = sizeof(udev->devpath);
 120                         strlcpy(udev->devpath, &bufline[2], count-1);
 121                         break;
 122                 case 'N':
 123                         if (count > sizeof(udev->name))
 124                                 count = sizeof(udev->name);
 125                         strlcpy(udev->name, &bufline[2], count-1);
 126                         break;
 127                 case 'M':
 128                         if (count > sizeof(line))
 129                                 count = sizeof(line);
 130                         strlcpy(line, &bufline[2], count-1);
 131                         sscanf(line, "%u:%u", &major, &minor);
 132                         udev->devt = makedev(major, minor);
 133                         break;
 134                 case 'S':
 135                         if (count > sizeof(line))
 136                                 count =  sizeof(line);
 137                         strlcpy(line, &bufline[2], count-1);
 138                         name_list_add(&udev->symlink_list, line, 0);
 139                         break;
 140                 case 'A':
 141                         if (count > sizeof(line))
 142                                 count =  sizeof(line);
 143                         strlcpy(line, &bufline[2], count-1);
 144                         udev->partitions = atoi(line);
 145                         break;
 146                 case 'R':
 147                         if (count > sizeof(line))
 148                                 count =  sizeof(line);
 149                         strlcpy(line, &bufline[2], count-1);
 150                         udev->ignore_remove = atoi(line);
 151                         break;
 152                 }
 153         }
 154         file_unmap(buf, bufsize);
 155
 156         if (udev->name[0] == '\0')
 157                 return -1;
 158
 159         return 0;
 160 }
 161
 162 int udev_db_delete_device(struct udevice *udev)
 163 {
 164         char filename[PATH_SIZE];
 165
 166         get_db_filename(udev->devpath, filename, sizeof(filename));
 167         unlink(filename);
 168
 169         return 0;
 170 }
 171
 172 int udev_db_get_device(struct udevice *udev, const char *devpath)
 173 {
 174         char filename[PATH_SIZE];
 175
 176         get_db_filename(devpath, filename, sizeof(filename));
 177
 178         if (parse_db_file(udev, filename) != 0)
 179                 return -1;
 180
 181         return 0;
 182 }
 183
 184 int udev_db_search_name(char *devpath, size_t len, const char *name)
 185 {
 186         DIR *dir;
 187
 188         dir = opendir(udev_db_path);
 189         if (dir == NULL) {
 190                 err("unable to open udev_db '%s'", udev_db_path);
 191                 return -1;
 192         }
 193
 194         while (1) {
 195                 struct dirent *ent;
 196                 char filename[PATH_SIZE];
 197                 char path[PATH_SIZE];
 198                 char nodename[PATH_SIZE];
 199                 char *bufline;
 200                 char *buf;
 201                 size_t bufsize;
 202                 size_t cur;
 203                 size_t count;
 204
 205                 ent = readdir(dir);
 206                 if (ent == NULL || ent->d_name[0] == '\0')
 207                         break;
 208
 209                 if (ent->d_name[0] == '.')
 210                         continue;
 211
 212                 snprintf(filename, sizeof(filename), "%s/%s", udev_db_path, ent->d_name);
 213                 filename[sizeof(filename)-1] = '\0';
 214                 dbg("looking at '%s'", filename);
 215
 216                 if (file_map(filename, &buf, &bufsize) != 0) {
 217                         err("unable to read db file '%s'", filename);
 218                         continue;
 219                 }
 220
 221                 cur = 0;
 222                 while (cur < bufsize) {
 223                         count = buf_get_line(buf, bufsize, cur);
 224                         bufline = &buf[cur];
 225                         cur += count+1;
 226
 227                         switch(bufline[0]) {
 228                         case 'P':
 229                                 if (count > sizeof(path))
 230                                         count = sizeof(path);
 231                                 strlcpy(path, &bufline[2], count-1);
 232                                 break;
 233                         case 'N':
 234                         case 'S':
 235                                 if (count > sizeof(nodename))
 236                                         count = sizeof(nodename);
 237                                 strlcpy(nodename, &bufline[2], count-1);
 238                                 dbg("compare '%s' '%s'", nodename, name);
 239                                 if (strcmp(nodename, name) == 0) {
 240                                         strlcpy(devpath, path, len);
 241                                         file_unmap(buf, bufsize);
 242                                         closedir(dir);
 243                                         return 0;
 244                                 }
 245                                 break;
 246                         default:
 247                                 continue;
 248                         }
 249                 }
 250                 file_unmap(buf, bufsize);
 251         }
 252
 253         closedir(dir);
 254         return -1;
 255 }
 256
 257 int udev_db_dump_names(int (*handler_function)(const char *path, const char *name))
 258 {
 259         DIR *dir;
 260
 261         dir = opendir(udev_db_path);
 262         if (dir == NULL) {
 263                 err("unable to open udev_db '%s'", udev_db_path);
 264                 return -1;
 265         }
 266
 267         while (1) {
 268                 struct dirent *ent;
 269                 char filename[PATH_SIZE];
 270                 char path[PATH_SIZE];
 271                 char nodename[PATH_SIZE];
 272                 char *bufline;
 273                 char *buf;
 274                 size_t bufsize;
 275                 size_t cur;
 276                 size_t count;
 277
 278                 ent = readdir(dir);
 279                 if (ent == NULL || ent->d_name[0] == '\0')
 280                         break;
 281
 282                 if (ent->d_name[0] == '.')
 283                         continue;
 284
 285                 snprintf(filename, sizeof(filename), "%s/%s", udev_db_path, ent->d_name);
 286                 filename[sizeof(filename)-1] = '\0';
 287                 dbg("looking at '%s'", filename);
 288
 289                 if (file_map(filename, &buf, &bufsize) != 0) {
 290                         err("unable to read db file '%s'", filename);
 291                         continue;
 292                 }
 293
 294                 path[0] = '\0';
 295                 nodename[0] = '\0';
 296                 cur = 0;
 297                 while (cur < bufsize) {
 298                         count = buf_get_line(buf, bufsize, cur);
 299                         bufline = &buf[cur];
 300                         cur += count+1;
 301
 302                         switch(bufline[0]) {
 303                         case 'P':
 304                                 if (count > sizeof(path))
 305                                         count = sizeof(path);
 306                                 strlcpy(path, &bufline[2], count-1);
 307                                 break;
 308                         case 'N':
 309                                 if (count > sizeof(nodename))
 310                                         count = sizeof(nodename);
 311                                 strlcpy(nodename, &bufline[2], count-1);
 312                                 break;
 313                         default:
 314                                 continue;
 315                         }
 316                 }
 317                 file_unmap(buf, bufsize);
 318
 319                 if (path[0] == '\0' || nodename[0] == '\0')
 320                         continue;
 321
 322                 if (handler_function(path, nodename) != 0)
 323                         break;
 324         }
 325
 326         closedir(dir);
 327         return 0;
 328 }