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