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 int udev_log;
  49 int udev_dev_d;
  50 int udev_hotplug_d;
  51
  52
  53 static int string_is_true(const char *str)
  54 {
  55         if (strcasecmp(str, "true") == 0)
  56                 return 1;
  57         if (strcasecmp(str, "yes") == 0)
  58                 return 1;
  59         if (strcasecmp(str, "1") == 0)
  60                 return 1;
  61         return 0;
  62 }
  63
  64 static void init_variables(void)
  65 {
  66         const char *env;
  67
  68         /* If any config values are specified, they will override these values. */
  69         strcpy(udev_root, UDEV_ROOT);
  70         strcpy(udev_db_path, UDEV_DB);
  71         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
  72         strcpy(udev_rules_filename, UDEV_RULES_FILE);
  73
  74         udev_log = string_is_true(UDEV_LOG_DEFAULT);
  75
  76         udev_dev_d = 1;
  77         env = getenv("UDEV_NO_DEVD");
  78         if (env && string_is_true(env))
  79                 udev_dev_d = 0;
  80
  81         udev_hotplug_d = 1;
  82         env = getenv("UDEV_NO_HOTPLUGD");
  83         if (env && string_is_true(env))
  84                 udev_hotplug_d = 0;
  85 }
  86
  87 static int parse_config_file(void)
  88 {
  89         char line[LINE_SIZE];
  90         char *bufline;
  91         char *temp;
  92         char *variable;
  93         char *value;
  94         char *buf;
  95         size_t bufsize;
  96         size_t cur;
  97         size_t count;
  98         int lineno;
  99         int retval = 0;
 100
 101         if (file_map(udev_config_filename, &buf, &bufsize) == 0) {
 102                 dbg("reading '%s' as config file", udev_config_filename);
 103         } else {
 104                 dbg("can't open '%s' as config file", udev_config_filename);
 105                 return -ENODEV;
 106         }
 107
 108         /* loop through the whole file */
 109         lineno = 0;
 110         cur = 0;
 111         while (cur < bufsize) {
 112                 count = buf_get_line(buf, bufsize, cur);
 113                 bufline = &buf[cur];
 114                 cur += count+1;
 115                 lineno++;
 116
 117                 if (count >= LINE_SIZE) {
 118                         info("line too long, conf line skipped %s, line %d",
 119                                         udev_config_filename, lineno);
 120                         continue;
 121                 }
 122
 123                 /* eat the whitespace */
 124                 while ((count > 0) && isspace(bufline[0])) {
 125                         bufline++;
 126                         count--;
 127                 }
 128                 if (count == 0)
 129                         continue;
 130
 131                 /* see if this is a comment */
 132                 if (bufline[0] == COMMENT_CHARACTER)
 133                         continue;
 134
 135                 strncpy(line, bufline, count);
 136                 line[count] = '\0';
 137                 temp = line;
 138                 dbg_parse("read '%s'", temp);
 139
 140                 retval = parse_get_pair(&temp, &variable, &value);
 141                 if (retval != 0)
 142                         info("%s:%d:%Zd: error parsing '%s'",
 143                              udev_config_filename, lineno, temp-line, temp);
 144
 145                 dbg_parse("variable='%s', value='%s'", variable, value);
 146
 147                 if (strcasecmp(variable, "udev_root") == 0) {
 148                         strfieldcpy(udev_root, value);
 149                         no_trailing_slash(udev_root);
 150                         continue;
 151                 }
 152
 153                 if (strcasecmp(variable, "udev_db") == 0) {
 154                         strfieldcpy(udev_db_path, value);
 155                         no_trailing_slash(udev_db_path);
 156                         continue;
 157                 }
 158
 159                 if (strcasecmp(variable, "udev_rules") == 0) {
 160                         strfieldcpy(udev_rules_filename, value);
 161                         no_trailing_slash(udev_rules_filename);
 162                         continue;
 163                 }
 164
 165                 if (strcasecmp(variable, "udev_log") == 0) {
 166                         udev_log = string_is_true(value);
 167                         continue;
 168                 }
 169         }
 170
 171         file_unmap(buf, bufsize);
 172         return retval;
 173 }
 174
 175 static void get_dirs(void)
 176 {
 177         char *temp;
 178         int retval;
 179
 180         retval = sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX);
 181         if (retval)
 182                 dbg("sysfs_get_mnt_path failed");
 183
 184         /* see if we should try to override any of the default values */
 185         if (getenv("UDEV_TEST") != NULL) {
 186                 temp = getenv("SYSFS_PATH");
 187                 if (temp != NULL) {
 188                         strfieldcpy(sysfs_path, temp);
 189                         no_trailing_slash(sysfs_path);
 190                 }
 191
 192                 temp = getenv("UDEV_CONFIG_FILE");
 193                 if (temp != NULL)
 194                         strfieldcpy(udev_config_filename, temp);
 195         }
 196
 197         parse_config_file();
 198         dbg("sysfs_path='%s'", sysfs_path);
 199         dbg("udev_root='%s'", udev_root);
 200         dbg("udev_config_filename='%s'", udev_config_filename);
 201         dbg("udev_db_path='%s'", udev_db_path);
 202         dbg("udev_rules_filename='%s'", udev_rules_filename);
 203         dbg("udev_log=%d", udev_log);
 204 }
 205
 206 void udev_init_config(void)
 207 {
 208         init_variables();
 209         get_dirs();
 210 }