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_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 mode_t default_mode;
  50 char default_owner[USER_SIZE];
  51 char default_group[USER_SIZE];
  52 int udev_log;
  53 int udev_dev_d;
  54 int udev_hotplug_d;
  55
  56
  57 static int string_is_true(const 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         const char *env;
  71
  72         /* If any config values are specified, they will override these values. */
  73         strcpy(udev_root, UDEV_ROOT);
  74         strcpy(udev_db_path, UDEV_DB);
  75         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
  76         strcpy(udev_rules_filename, UDEV_RULES_FILE);
  77         strcpy(udev_permissions_filename, UDEV_PERMISSION_FILE);
  78
  79         strcpy(default_owner, "root");
  80         strcpy(default_group, "root");
  81         default_mode = 0600;
  82
  83         udev_log = string_is_true(UDEV_LOG_DEFAULT);
  84
  85         udev_dev_d = 1;
  86         env = getenv("UDEV_NO_DEVD");
  87         if (env && string_is_true(env))
  88                 udev_dev_d = 0;
  89
  90         udev_hotplug_d = 1;
  91         env = getenv("UDEV_NO_HOTPLUGD");
  92         if (env && string_is_true(env))
  93                 udev_hotplug_d = 0;
  94 }
  95
  96 int parse_get_pair(char **orig_string, char **left, char **right)
  97 {
  98         char *temp;
  99         char *string = *orig_string;
 100
 101         if (!string)
 102                 return -ENODEV;
 103
 104         /* eat any whitespace */
 105         while (isspace(*string) || *string == ',')
 106                 ++string;
 107
 108         /* split based on '=' */
 109         temp = strsep(&string, "=");
 110         *left = temp;
 111         if (!string)
 112                 return -ENODEV;
 113
 114         /* take the right side and strip off the '"' */
 115         while (isspace(*string))
 116                 ++string;
 117         if (*string == '"')
 118                 ++string;
 119         else
 120                 return -ENODEV;
 121
 122         temp = strsep(&string, "\"");
 123         if (!string || *temp == '\0')
 124                 return -ENODEV;
 125         *right = temp;
 126         *orig_string = string;
 127
 128         return 0;
 129 }
 130
 131 static int parse_config_file(void)
 132 {
 133         char line[LINE_SIZE];
 134         char *bufline;
 135         char *temp;
 136         char *variable;
 137         char *value;
 138         char *buf;
 139         size_t bufsize;
 140         size_t cur;
 141         size_t count;
 142         int lineno;
 143         int retval = 0;
 144
 145         if (file_map(udev_config_filename, &buf, &bufsize) == 0) {
 146                 dbg("reading '%s' as config file", udev_config_filename);
 147         } else {
 148                 dbg("can't open '%s' as config file", udev_config_filename);
 149                 return -ENODEV;
 150         }
 151
 152         /* loop through the whole file */
 153         lineno = 0;
 154         cur = 0;
 155         while (cur < bufsize) {
 156                 count = buf_get_line(buf, bufsize, cur);
 157                 bufline = &buf[cur];
 158                 cur += count+1;
 159                 lineno++;
 160
 161                 if (count >= LINE_SIZE) {
 162                         info("line too long, conf line skipped %s, line %d",
 163                                         udev_config_filename, lineno);
 164                         continue;
 165                 }
 166
 167                 /* eat the whitespace */
 168                 while ((count > 0) && isspace(bufline[0])) {
 169                         bufline++;
 170                         count--;
 171                 }
 172                 if (count == 0)
 173                         continue;
 174
 175                 /* see if this is a comment */
 176                 if (bufline[0] == COMMENT_CHARACTER)
 177                         continue;
 178
 179                 strncpy(line, bufline, count);
 180                 line[count] = '\0';
 181                 temp = line;
 182                 dbg_parse("read '%s'", temp);
 183
 184                 retval = parse_get_pair(&temp, &variable, &value);
 185                 if (retval != 0)
 186                         info("%s:%d:%Zd: error parsing '%s'",
 187                              udev_config_filename, lineno, temp-line, temp);
 188
 189                 dbg_parse("variable='%s', value='%s'", variable, value);
 190
 191                 if (strcasecmp(variable, "udev_root") == 0) {
 192                         strfieldcpy(udev_root, value);
 193                         no_trailing_slash(udev_root);
 194                         continue;
 195                 }
 196
 197                 if (strcasecmp(variable, "udev_db") == 0) {
 198                         strfieldcpy(udev_db_path, value);
 199                         no_trailing_slash(udev_db_path);
 200                         continue;
 201                 }
 202
 203                 if (strcasecmp(variable, "udev_rules") == 0) {
 204                         strfieldcpy(udev_rules_filename, value);
 205                         no_trailing_slash(udev_rules_filename);
 206                         continue;
 207                 }
 208
 209                 if (strcasecmp(variable, "udev_permissions") == 0) {
 210                         strfieldcpy(udev_permissions_filename, value);
 211                         no_trailing_slash(udev_permissions_filename);
 212                         continue;
 213                 }
 214
 215                 if (strcasecmp(variable, "default_mode") == 0) {
 216                         default_mode = strtol(value, NULL, 8);
 217                         continue;
 218                 }
 219
 220                 if (strcasecmp(variable, "default_owner") == 0) {
 221                         strfieldcpy(default_owner, value);
 222                         continue;
 223                 }
 224
 225                 if (strcasecmp(variable, "default_group") == 0) {
 226                         strfieldcpy(default_group, value);
 227                         continue;
 228                 }
 229
 230                 if (strcasecmp(variable, "udev_log") == 0) {
 231                         udev_log = string_is_true(value);
 232                         continue;
 233                 }
 234
 235                 info("%s:%d:%Zd: unknown key '%s'",
 236                      udev_config_filename, lineno, temp-line, temp);
 237         }
 238
 239         file_unmap(buf, bufsize);
 240         return retval;
 241 }
 242
 243 static void get_dirs(void)
 244 {
 245         char *temp;
 246         int retval;
 247
 248         retval = sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX);
 249         if (retval)
 250                 dbg("sysfs_get_mnt_path failed");
 251
 252         /* see if we should try to override any of the default values */
 253         if (getenv("UDEV_TEST") != NULL) {
 254                 temp = getenv("SYSFS_PATH");
 255                 if (temp != NULL) {
 256                         strfieldcpy(sysfs_path, temp);
 257                         no_trailing_slash(sysfs_path);
 258                 }
 259
 260                 temp = getenv("UDEV_CONFIG_FILE");
 261                 if (temp != NULL)
 262                         strfieldcpy(udev_config_filename, temp);
 263         }
 264
 265         dbg("sysfs_path='%s'", sysfs_path);
 266         dbg_parse("udev_root = %s", udev_root);
 267         dbg_parse("udev_config_filename = %s", udev_config_filename);
 268         dbg_parse("udev_db_path = %s", udev_db_path);
 269         dbg_parse("udev_rules_filename = %s", udev_rules_filename);
 270         dbg_parse("udev_permissions_filename = %s", udev_permissions_filename);
 271         dbg_parse("udev_log = %d", udev_log);
 272
 273         parse_config_file();
 274
 275         dbg("udev_root = %s", udev_root);
 276         dbg("udev_config_filename = %s", udev_config_filename);
 277         dbg("udev_db_path = %s", udev_db_path);
 278         dbg("udev_rules_filename = %s", udev_rules_filename);
 279         dbg("udev_permissions_filename = %s", udev_permissions_filename);
 280         dbg("udev_log = %d", udev_log);
 281 }
 282
 283 void udev_init_config(void)
 284 {
 285         init_variables();
 286         get_dirs();
 287 }