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_utils.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_path[PATH_MAX+NAME_MAX];
  46 char udev_rules_filename[PATH_MAX+NAME_MAX];
  47 char udev_config_filename[PATH_MAX+NAME_MAX];
  48 mode_t default_mode;
  49 char default_owner[USER_SIZE];
  50 char default_group[USER_SIZE];
  51 int udev_log;
  52 int udev_dev_d;
  53 int udev_hotplug_d;
  54
  55
  56 static int string_is_true(const 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         const char *env;
  70
  71         /* If any config values are specified, they will override these values. */
  72         strcpy(udev_root, UDEV_ROOT);
  73         strcpy(udev_db_path, UDEV_DB);
  74         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
  75         strcpy(udev_rules_filename, UDEV_RULES_FILE);
  76
  77         strcpy(default_owner, "root");
  78         strcpy(default_group, "root");
  79         default_mode = 0600;
  80
  81         udev_log = string_is_true(UDEV_LOG_DEFAULT);
  82
  83         udev_dev_d = 1;
  84         env = getenv("UDEV_NO_DEVD");
  85         if (env && string_is_true(env))
  86                 udev_dev_d = 0;
  87
  88         udev_hotplug_d = 1;
  89         env = getenv("UDEV_NO_HOTPLUGD");
  90         if (env && string_is_true(env))
  91                 udev_hotplug_d = 0;
  92 }
  93
  94 int parse_get_pair(char **orig_string, char **left, char **right)
  95 {
  96         char *temp;
  97         char *string = *orig_string;
  98
  99         if (!string)
 100                 return -ENODEV;
 101
 102         /* eat any whitespace */
 103         while (isspace(*string) || *string == ',')
 104                 ++string;
 105
 106         /* split based on '=' */
 107         temp = strsep(&string, "=");
 108         *left = temp;
 109         if (!string)
 110                 return -ENODEV;
 111
 112         /* take the right side and strip off the '"' */
 113         while (isspace(*string))
 114                 ++string;
 115         if (*string == '"')
 116                 ++string;
 117         else
 118                 return -ENODEV;
 119
 120         temp = strsep(&string, "\"");
 121         if (!string || *temp == '\0')
 122                 return -ENODEV;
 123         *right = temp;
 124         *orig_string = string;
 125
 126         return 0;
 127 }
 128
 129 static int parse_config_file(void)
 130 {
 131         char line[LINE_SIZE];
 132         char *bufline;
 133         char *temp;
 134         char *variable;
 135         char *value;
 136         char *buf;
 137         size_t bufsize;
 138         size_t cur;
 139         size_t count;
 140         int lineno;
 141         int retval = 0;
 142
 143         if (file_map(udev_config_filename, &buf, &bufsize) == 0) {
 144                 dbg("reading '%s' as config file", udev_config_filename);
 145         } else {
 146                 dbg("can't open '%s' as config file", udev_config_filename);
 147                 return -ENODEV;
 148         }
 149
 150         /* loop through the whole file */
 151         lineno = 0;
 152         cur = 0;
 153         while (cur < bufsize) {
 154                 count = buf_get_line(buf, bufsize, cur);
 155                 bufline = &buf[cur];
 156                 cur += count+1;
 157                 lineno++;
 158
 159                 if (count >= LINE_SIZE) {
 160                         info("line too long, conf line skipped %s, line %d",
 161                                         udev_config_filename, lineno);
 162                         continue;
 163                 }
 164
 165                 /* eat the whitespace */
 166                 while ((count > 0) && isspace(bufline[0])) {
 167                         bufline++;
 168                         count--;
 169                 }
 170                 if (count == 0)
 171                         continue;
 172
 173                 /* see if this is a comment */
 174                 if (bufline[0] == COMMENT_CHARACTER)
 175                         continue;
 176
 177                 strncpy(line, bufline, count);
 178                 line[count] = '\0';
 179                 temp = line;
 180                 dbg_parse("read '%s'", temp);
 181
 182                 retval = parse_get_pair(&temp, &variable, &value);
 183                 if (retval != 0)
 184                         info("%s:%d:%Zd: error parsing '%s'",
 185                              udev_config_filename, lineno, temp-line, temp);
 186
 187                 dbg_parse("variable='%s', value='%s'", variable, value);
 188
 189                 if (strcasecmp(variable, "udev_root") == 0) {
 190                         strfieldcpy(udev_root, value);
 191                         no_trailing_slash(udev_root);
 192                         continue;
 193                 }
 194
 195                 if (strcasecmp(variable, "udev_db") == 0) {
 196                         strfieldcpy(udev_db_path, value);
 197                         no_trailing_slash(udev_db_path);
 198                         continue;
 199                 }
 200
 201                 if (strcasecmp(variable, "udev_rules") == 0) {
 202                         strfieldcpy(udev_rules_filename, value);
 203                         no_trailing_slash(udev_rules_filename);
 204                         continue;
 205                 }
 206
 207                 if (strcasecmp(variable, "default_mode") == 0) {
 208                         default_mode = strtol(value, NULL, 8);
 209                         continue;
 210                 }
 211
 212                 if (strcasecmp(variable, "default_owner") == 0) {
 213                         strfieldcpy(default_owner, value);
 214                         continue;
 215                 }
 216
 217                 if (strcasecmp(variable, "default_group") == 0) {
 218                         strfieldcpy(default_group, 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_trailing_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_path = %s", udev_db_path);
 261         dbg_parse("udev_rules_filename = %s", udev_rules_filename);
 262         dbg_parse("udev_log = %d", udev_log);
 263
 264         parse_config_file();
 265
 266         dbg("udev_root = %s", udev_root);
 267         dbg("udev_config_filename = %s", udev_config_filename);
 268         dbg("udev_db_path = %s", udev_db_path);
 269         dbg("udev_rules_filename = %s", udev_rules_filename);
 270         dbg("udev_log = %d", udev_log);
 271 }
 272
 273 void udev_init_config(void)
 274 {
 275         init_variables();
 276         get_dirs();
 277 }