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 #include <syslog.h>
  32
  33 #include "libsysfs/sysfs/libsysfs.h"
  34 #include "udev_libc_wrapper.h"
  35 #include "udev.h"
  36 #include "udev_utils.h"
  37 #include "udev_version.h"
  38 #include "logging.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_config_filename[PATH_SIZE];
  45 char udev_rules_filename[PATH_SIZE];
  46 int udev_log_priority;
  47 int udev_run;
  48 int udev_hotplug_d;
  49
  50 static int get_key(char **line, char **key, char **value)
  51 {
  52         char *linepos;
  53         char *temp;
  54
  55         linepos = *line;
  56         if (!linepos)
  57                 return -1;
  58
  59         /* skip whitespace */
  60         while (isspace(linepos[0]))
  61                 linepos++;
  62
  63         /* get the key */
  64         *key = linepos;
  65         while (1) {
  66                 linepos++;
  67                 if (linepos[0] == '\0')
  68                         return -1;
  69                 if (isspace(linepos[0]))
  70                         break;
  71                 if (linepos[0] == '=')
  72                         break;
  73         }
  74
  75         /* terminate key */
  76         linepos[0] = '\0';
  77         linepos++;
  78
  79         /* skip whitespace */
  80         while (isspace(linepos[0]))
  81                 linepos++;
  82
  83         /* get the value*/
  84         if (linepos[0] == '"')
  85                 linepos++;
  86         else
  87                 return -1;
  88         *value = linepos;
  89
  90         temp = strchr(linepos, '"');
  91         if (!temp)
  92                 return -1;
  93         temp[0] = '\0';
  94
  95         return 0;
  96 }
  97
  98 static int parse_config_file(void)
  99 {
 100         char line[LINE_SIZE];
 101         char *bufline;
 102         char *linepos;
 103         char *variable;
 104         char *value;
 105         char *buf;
 106         size_t bufsize;
 107         size_t cur;
 108         size_t count;
 109         int lineno;
 110         int retval = 0;
 111
 112         if (file_map(udev_config_filename, &buf, &bufsize) != 0) {
 113                 err("can't open '%s' as config file", udev_config_filename);
 114                 return -ENODEV;
 115         }
 116
 117         /* loop through the whole file */
 118         lineno = 0;
 119         cur = 0;
 120         while (cur < bufsize) {
 121                 count = buf_get_line(buf, bufsize, cur);
 122                 bufline = &buf[cur];
 123                 cur += count+1;
 124                 lineno++;
 125
 126                 if (count >= sizeof(line)) {
 127                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
 128                         continue;
 129                 }
 130
 131                 /* eat the whitespace */
 132                 while ((count > 0) && isspace(bufline[0])) {
 133                         bufline++;
 134                         count--;
 135                 }
 136                 if (count == 0)
 137                         continue;
 138
 139                 /* see if this is a comment */
 140                 if (bufline[0] == COMMENT_CHARACTER)
 141                         continue;
 142
 143                 strlcpy(line, bufline, count+1);
 144
 145                 linepos = line;
 146                 retval = get_key(&linepos, &variable, &value);
 147                 if (retval != 0) {
 148                         err("error parsing %s, line %d:%d", udev_config_filename, lineno, (int) (linepos-line));
 149                         continue;
 150                 }
 151
 152                 if (strcasecmp(variable, "udev_root") == 0) {
 153                         strlcpy(udev_root, value, sizeof(udev_root));
 154                         remove_trailing_char(udev_root, '/');
 155                         continue;
 156                 }
 157
 158                 if (strcasecmp(variable, "udev_db") == 0) {
 159                         strlcpy(udev_db_path, value, sizeof(udev_db_path));
 160                         remove_trailing_char(udev_db_path, '/');
 161                         continue;
 162                 }
 163
 164                 if (strcasecmp(variable, "udev_rules") == 0) {
 165                         strlcpy(udev_rules_filename, value, sizeof(udev_rules_filename));
 166                         remove_trailing_char(udev_rules_filename, '/');
 167                         continue;
 168                 }
 169
 170                 if (strcasecmp(variable, "udev_log") == 0) {
 171                         udev_log_priority = log_priority(value);
 172                         continue;
 173                 }
 174         }
 175
 176         file_unmap(buf, bufsize);
 177         return retval;
 178 }
 179
 180 void udev_init_config(void)
 181 {
 182         const char *env;
 183
 184         strcpy(udev_root, UDEV_ROOT);
 185         strcpy(udev_db_path, UDEV_DB);
 186         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
 187         strcpy(udev_rules_filename, UDEV_RULES_FILE);
 188         udev_log_priority = LOG_ERR;
 189         udev_run = 1;
 190         udev_hotplug_d = 1;
 191         sysfs_get_mnt_path(sysfs_path, sizeof(sysfs_path));
 192
 193         /* disable RUN key execution */
 194         env = getenv("UDEV_RUN");
 195         if (env && !string_is_true(env))
 196                 udev_run = 0;
 197
 198         env = getenv("UDEV_NO_HOTPLUGD");
 199         if (env && string_is_true(env))
 200                 udev_hotplug_d = 0;
 201
 202         env = getenv("UDEV_CONFIG_FILE");
 203         if (env) {
 204                 strlcpy(udev_config_filename, env, sizeof(udev_config_filename));
 205                 remove_trailing_char(udev_config_filename, '/');
 206         }
 207
 208         parse_config_file();
 209
 210         env = getenv("UDEV_LOG");
 211         if (env)
 212                 udev_log_priority = log_priority(env);
 213
 214         dbg("sysfs_path='%s'", sysfs_path);
 215         dbg("UDEV_CONFIG_FILE='%s'", udev_config_filename);
 216         dbg("udev_root='%s'", udev_root);
 217         dbg("udev_db='%s'", udev_db_path);
 218         dbg("udev_rules='%s'", udev_rules_filename);
 219         dbg("udev_log=%d", udev_log_priority);
 220 }