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 #include <stdlib.h>
  25 #include <string.h>
  26 #include <stdio.h>
  27 #include <fcntl.h>
  28 #include <unistd.h>
  29 #include <errno.h>
  30 #include <ctype.h>
  31
  32 #include "libsysfs/sysfs/libsysfs.h"
  33 #include "udev_libc_wrapper.h"
  34 #include "udev.h"
  35 #include "udev_utils.h"
  36 #include "udev_version.h"
  37 #include "logging.h"
  38 #include "udev_rules.h"
  39
  40 /* global variables */
  41 char sysfs_path[PATH_SIZE];
  42 char udev_root[PATH_SIZE];
  43 char udev_db_path[PATH_SIZE];
  44 char udev_rules_filename[PATH_SIZE];
  45 char udev_config_filename[PATH_SIZE];
  46 int udev_log;
  47 int udev_dev_d;
  48 int udev_hotplug_d;
  49
  50
  51 static int string_is_true(const char *str)
  52 {
  53         if (strcasecmp(str, "true") == 0)
  54                 return 1;
  55         if (strcasecmp(str, "yes") == 0)
  56                 return 1;
  57         if (strcasecmp(str, "1") == 0)
  58                 return 1;
  59         return 0;
  60 }
  61
  62 static void init_variables(void)
  63 {
  64         const char *env;
  65
  66         /* If any config values are specified, they will override these values. */
  67         strcpy(udev_root, UDEV_ROOT);
  68         strcpy(udev_db_path, UDEV_DB);
  69         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
  70         strcpy(udev_rules_filename, UDEV_RULES_FILE);
  71
  72         udev_log = string_is_true(UDEV_LOG_DEFAULT);
  73
  74         udev_dev_d = 1;
  75         env = getenv("UDEV_NO_DEVD");
  76         if (env && string_is_true(env))
  77                 udev_dev_d = 0;
  78
  79         udev_hotplug_d = 1;
  80         env = getenv("UDEV_NO_HOTPLUGD");
  81         if (env && string_is_true(env))
  82                 udev_hotplug_d = 0;
  83 }
  84
  85 static int parse_config_file(void)
  86 {
  87         char line[LINE_SIZE];
  88         char *bufline;
  89         char *temp;
  90         char *variable;
  91         char *value;
  92         char *buf;
  93         size_t bufsize;
  94         size_t cur;
  95         size_t count;
  96         int lineno;
  97         int retval = 0;
  98
  99         if (file_map(udev_config_filename, &buf, &bufsize) != 0) {
 100                 dbg("can't open '%s' as config file", udev_config_filename);
 101                 return -ENODEV;
 102         }
 103         dbg("reading '%s' as config file", udev_config_filename);
 104
 105         /* loop through the whole file */
 106         lineno = 0;
 107         cur = 0;
 108         while (cur < bufsize) {
 109                 count = buf_get_line(buf, bufsize, cur);
 110                 bufline = &buf[cur];
 111                 cur += count+1;
 112                 lineno++;
 113
 114                 if (count >= sizeof(line)) {
 115                         info("line too long, conf line skipped %s, line %d",
 116                                         udev_config_filename, lineno);
 117                         continue;
 118                 }
 119
 120                 /* eat the whitespace */
 121                 while ((count > 0) && isspace(bufline[0])) {
 122                         bufline++;
 123                         count--;
 124                 }
 125                 if (count == 0)
 126                         continue;
 127
 128                 /* see if this is a comment */
 129                 if (bufline[0] == COMMENT_CHARACTER)
 130                         continue;
 131
 132                 strlcpy(line, bufline, count);
 133                 temp = line;
 134                 dbg("read '%s'", temp);
 135
 136                 retval = parse_get_pair(&temp, &variable, &value);
 137                 if (retval != 0)
 138                         info("%s:%d:%Zd: error parsing '%s'",
 139                              udev_config_filename, lineno, temp-line, temp);
 140
 141                 dbg("variable='%s', value='%s'", variable, value);
 142
 143                 if (strcasecmp(variable, "udev_root") == 0) {
 144                         strlcpy(udev_root, value, sizeof(udev_root));
 145                         no_trailing_slash(udev_root);
 146                         continue;
 147                 }
 148
 149                 if (strcasecmp(variable, "udev_db") == 0) {
 150                         strlcpy(udev_db_path, value, sizeof(udev_db_path));
 151                         no_trailing_slash(udev_db_path);
 152                         continue;
 153                 }
 154
 155                 if (strcasecmp(variable, "udev_rules") == 0) {
 156                         strlcpy(udev_rules_filename, value, sizeof(udev_rules_filename));
 157                         no_trailing_slash(udev_rules_filename);
 158                         continue;
 159                 }
 160
 161                 if (strcasecmp(variable, "udev_log") == 0) {
 162                         udev_log = string_is_true(value);
 163                         continue;
 164                 }
 165         }
 166
 167         file_unmap(buf, bufsize);
 168         return retval;
 169 }
 170
 171 static void get_dirs(void)
 172 {
 173         char *temp;
 174         int retval;
 175
 176         retval = sysfs_get_mnt_path(sysfs_path, sizeof(sysfs_path));
 177         if (retval)
 178                 dbg("sysfs_get_mnt_path failed");
 179
 180         /* see if we should try to override any of the default values */
 181         if (getenv("UDEV_TEST") != NULL) {
 182                 temp = getenv("SYSFS_PATH");
 183                 if (temp != NULL) {
 184                         strlcpy(sysfs_path, temp, sizeof(sysfs_path));
 185                         no_trailing_slash(sysfs_path);
 186                 }
 187
 188                 temp = getenv("UDEV_CONFIG_FILE");
 189                 if (temp != NULL)
 190                         strlcpy(udev_config_filename, temp, sizeof(udev_config_filename));
 191         }
 192
 193         parse_config_file();
 194         dbg("sysfs_path='%s'", sysfs_path);
 195         dbg("udev_root='%s'", udev_root);
 196         dbg("udev_config_filename='%s'", udev_config_filename);
 197         dbg("udev_db_path='%s'", udev_db_path);
 198         dbg("udev_rules_filename='%s'", udev_rules_filename);
 199         dbg("udev_log=%d", udev_log);
 200 }
 201
 202 void udev_init_config(void)
 203 {
 204         init_variables();
 205         get_dirs();
 206 }