udev_config.c

   1 /*
   2  * udev_config.c
   3  *
   4  * Userspace devfs
   5  *
   6  * Copyright (C) 2003,2004 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 /* define this to enable parsing debugging */
  25 /* #define DEBUG_PARSER */
  26
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <stdio.h>
  30 #include <fcntl.h>
  31 #include <unistd.h>
  32 #include <errno.h>
  33 #include <ctype.h>
  34
  35 #include "libsysfs/sysfs/libsysfs.h"
  36 #include "udev.h"
  37 #include "udev_lib.h"
  38 #include "udev_version.h"
  39 #include "logging.h"
  40 #include "namedev.h"
  41
  42 /* global variables */
  43 char sysfs_path[SYSFS_PATH_MAX];
  44 char udev_root[PATH_MAX];
  45 char udev_db_filename[PATH_MAX+NAME_MAX];
  46 char udev_permissions_filename[PATH_MAX+NAME_MAX];
  47 char udev_rules_filename[PATH_MAX+NAME_MAX];
  48 char udev_config_filename[PATH_MAX+NAME_MAX];
  49 char default_mode_str[MODE_SIZE];
  50 char default_owner_str[OWNER_SIZE];
  51 char default_group_str[GROUP_SIZE];
  52 int udev_log;
  53 int udev_sleep;
  54 int udev_dev_d;
  55
  56
  57 static int string_is_true(char *str)
  58 {
  59         if (strcasecmp(str, "true") == 0)
  60                 return 1;
  61         if (strcasecmp(str, "yes") == 0)
  62                 return 1;
  63         if (strcasecmp(str, "1") == 0)
  64                 return 1;
  65         return 0;
  66 }
  67
  68 static void init_variables(void)
  69 {
  70         char *env;
  71
  72         /* fill up the defaults.
  73          * If any config values are specified, they will
  74          * override these values. */
  75         strfieldcpy(udev_root, UDEV_ROOT);
  76         strfieldcpy(udev_db_filename, UDEV_DB);
  77         strfieldcpy(udev_config_filename, UDEV_CONFIG_FILE);
  78         strfieldcpy(udev_rules_filename, UDEV_RULES_FILE);
  79         strfieldcpy(udev_permissions_filename, UDEV_PERMISSION_FILE);
  80         udev_log = string_is_true(UDEV_LOG_DEFAULT);
  81
  82         udev_sleep = 1;
  83         env = getenv("UDEV_NO_SLEEP");
  84         if (env && string_is_true(env))
  85                 udev_sleep = 0;
  86
  87         udev_dev_d = 1;
  88         env = getenv("UDEV_NO_DEVD");
  89         if (env && string_is_true(env))
  90                 udev_dev_d = 0;
  91 }
  92
  93 int parse_get_pair(char **orig_string, char **left, char **right)
  94 {
  95         char *temp;
  96         char *string = *orig_string;
  97
  98         if (!string)
  99                 return -ENODEV;
 100
 101         /* eat any whitespace */
 102         while (isspace(*string) || *string == ',')
 103                 ++string;
 104
 105         /* split based on '=' */
 106         temp = strsep(&string, "=");
 107         *left = temp;
 108         if (!string)
 109                 return -ENODEV;
 110
 111         /* take the right side and strip off the '"' */
 112         while (isspace(*string))
 113                 ++string;
 114         if (*string == '"')
 115                 ++string;
 116         else
 117                 return -ENODEV;
 118
 119         temp = strsep(&string, "\"");
 120         if (!string || *temp == '\0')
 121                 return -ENODEV;
 122         *right = temp;
 123         *orig_string = string;
 124
 125         return 0;
 126 }
 127
 128 static int parse_config_file(void)
 129 {
 130         char line[255];
 131         char *temp;
 132         char *variable;
 133         char *value;
 134         char *buf;
 135         size_t bufsize;
 136         size_t cur;
 137         size_t count;
 138         int lineno;
 139         int retval = 0;
 140
 141         if (file_map(udev_config_filename, &buf, &bufsize) == 0) {
 142                 dbg("reading '%s' as config file", udev_config_filename);
 143         } else {
 144                 dbg("can't open '%s' as config file", udev_config_filename);
 145                 return -ENODEV;
 146         }
 147
 148         /* loop through the whole file */
 149         lineno = 0;
 150         cur = 0;
 151         while (1) {
 152                 count = buf_get_line(buf, bufsize, cur);
 153
 154                 strncpy(line, buf + cur, count);
 155                 line[count] = '\0';
 156                 temp = line;
 157                 lineno++;
 158
 159                 cur += count+1;
 160                 if (cur > bufsize)
 161                         break;
 162
 163                 dbg_parse("read '%s'", temp);
 164
 165                 /* eat the whitespace at the beginning of the line */
 166                 while (isspace(*temp))
 167                         ++temp;
 168
 169                 /* empty line? */
 170                 if (*temp == 0x00)
 171                         continue;
 172
 173                 /* see if this is a comment */
 174                 if (*temp == COMMENT_CHARACTER)
 175                         continue;
 176
 177                 retval = parse_get_pair(&temp, &variable, &value);
 178                 if (retval != 0)
 179                         info("%s:%d:%Zd: error parsing '%s'",
 180                              udev_config_filename, lineno, temp-line, temp);
 181
 182                 dbg_parse("variable='%s', value='%s'", variable, value);
 183
 184                 if (strcasecmp(variable, "udev_root") == 0) {
 185                         strfieldcpy(udev_root, value);
 186                         leading_slash(udev_root);
 187                         continue;
 188                 }
 189
 190                 if (strcasecmp(variable, "udev_db") == 0) {
 191                         strfieldcpy(udev_db_filename, value);
 192                         continue;
 193                 }
 194
 195                 if (strcasecmp(variable, "udev_rules") == 0) {
 196                         strfieldcpy(udev_rules_filename, value);
 197                         no_leading_slash(udev_rules_filename);
 198                         continue;
 199                 }
 200
 201                 if (strcasecmp(variable, "udev_permissions") == 0) {
 202                         strfieldcpy(udev_permissions_filename, value);
 203                         no_leading_slash(udev_permissions_filename);
 204                         continue;
 205                 }
 206
 207                 if (strcasecmp(variable, "default_mode") == 0) {
 208                         strfieldcpy(default_mode_str, value);
 209                         continue;
 210                 }
 211
 212                 if (strcasecmp(variable, "default_owner") == 0) {
 213                         strfieldcpy(default_owner_str, value);
 214                         continue;
 215                 }
 216
 217                 if (strcasecmp(variable, "default_group") == 0) {
 218                         strfieldcpy(default_group_str, value);
 219                         continue;
 220                 }
 221
 222                 if (strcasecmp(variable, "udev_log") == 0) {
 223                         udev_log = string_is_true(value);
 224                         continue;
 225                 }
 226
 227                 info("%s:%d:%Zd: unknown key '%s'",
 228                      udev_config_filename, lineno, temp-line, temp);
 229         }
 230
 231         file_unmap(buf, bufsize);
 232         return retval;
 233 }
 234
 235 static void get_dirs(void)
 236 {
 237         char *temp;
 238         int retval;
 239
 240         retval = sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX);
 241         if (retval)
 242                 dbg("sysfs_get_mnt_path failed");
 243
 244         /* see if we should try to override any of the default values */
 245         if (getenv("UDEV_TEST") != NULL) {
 246                 temp = getenv("SYSFS_PATH");
 247                 if (temp != NULL) {
 248                         strfieldcpy(sysfs_path, temp);
 249                         no_leading_slash(sysfs_path);
 250                 }
 251
 252                 temp = getenv("UDEV_CONFIG_FILE");
 253                 if (temp != NULL)
 254                         strfieldcpy(udev_config_filename, temp);
 255         }
 256
 257         dbg("sysfs_path='%s'", sysfs_path);
 258         dbg_parse("udev_root = %s", udev_root);
 259         dbg_parse("udev_config_filename = %s", udev_config_filename);
 260         dbg_parse("udev_db_filename = %s", udev_db_filename);
 261         dbg_parse("udev_rules_filename = %s", udev_rules_filename);
 262         dbg_parse("udev_permissions_filename = %s", udev_permissions_filename);
 263         dbg_parse("udev_log = %d", udev_log);
 264
 265         parse_config_file();
 266
 267         dbg("udev_root = %s", udev_root);
 268         dbg("udev_config_filename = %s", udev_config_filename);
 269         dbg("udev_db_filename = %s", udev_db_filename);
 270         dbg("udev_rules_filename = %s", udev_rules_filename);
 271         dbg("udev_permissions_filename = %s", udev_permissions_filename);
 272         dbg("udev_log_str = %d", udev_log);
 273 }
 274
 275 void udev_init_config(void)
 276 {
 277         init_variables();
 278         get_dirs();
 279 }