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_dev_d;
  49 int udev_hotplug_d;
  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 int log_priority(const char *priority)
  63 {
  64         char *endptr;
  65         int prio;
  66
  67         prio = strtol(priority, &endptr, 10);
  68         if (endptr[0] == '\0')
  69                 return prio;
  70         if (strncasecmp(priority, "err", 3) == 0)
  71                 return LOG_ERR;
  72         if (strcasecmp(priority, "info") == 0)
  73                 return LOG_INFO;
  74         if (strcasecmp(priority, "debug") == 0)
  75                 return LOG_DEBUG;
  76         if (string_is_true(priority))
  77                 return LOG_ERR;
  78
  79         return 0;
  80 }
  81
  82 static int get_key(char **line, char **key, char **value)
  83 {
  84         char *linepos;
  85         char *temp;
  86
  87         linepos = *line;
  88         if (!linepos)
  89                 return -1;
  90
  91         /* skip whitespace */
  92         while (isspace(linepos[0]))
  93                 linepos++;
  94
  95         /* get the key */
  96         *key = linepos;
  97         while (1) {
  98                 linepos++;
  99                 if (linepos[0] == '\0')
 100                         return -1;
 101                 if (isspace(linepos[0]))
 102                         break;
 103                 if (linepos[0] == '=')
 104                         break;
 105         }
 106
 107         /* terminate key */
 108         linepos[0] = '\0';
 109         linepos++;
 110
 111         /* skip whitespace */
 112         while (isspace(linepos[0]))
 113                 linepos++;
 114
 115         /* get the value*/
 116         if (linepos[0] == '"')
 117                 linepos++;
 118         else
 119                 return -1;
 120         *value = linepos;
 121
 122         temp = strchr(linepos, '"');
 123         if (!temp)
 124                 return -1;
 125         temp[0] = '\0';
 126
 127         return 0;
 128 }
 129
 130 static int parse_config_file(void)
 131 {
 132         char line[LINE_SIZE];
 133         char *bufline;
 134         char *linepos;
 135         char *variable;
 136         char *value;
 137         char *buf;
 138         size_t bufsize;
 139         size_t cur;
 140         size_t count;
 141         int lineno;
 142         int retval = 0;
 143
 144         if (file_map(udev_config_filename, &buf, &bufsize) != 0) {
 145                 err("can't open '%s' as config file", udev_config_filename);
 146                 return -ENODEV;
 147         }
 148
 149         /* loop through the whole file */
 150         lineno = 0;
 151         cur = 0;
 152         while (cur < bufsize) {
 153                 count = buf_get_line(buf, bufsize, cur);
 154                 bufline = &buf[cur];
 155                 cur += count+1;
 156                 lineno++;
 157
 158                 if (count >= sizeof(line)) {
 159                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
 160                         continue;
 161                 }
 162
 163                 /* eat the whitespace */
 164                 while ((count > 0) && isspace(bufline[0])) {
 165                         bufline++;
 166                         count--;
 167                 }
 168                 if (count == 0)
 169                         continue;
 170
 171                 /* see if this is a comment */
 172                 if (bufline[0] == COMMENT_CHARACTER)
 173                         continue;
 174
 175                 strlcpy(line, bufline, count+1);
 176
 177                 linepos = line;
 178                 retval = get_key(&linepos, &variable, &value);
 179                 if (retval != 0) {
 180                         err("error parsing %s, line %d:%d", udev_config_filename, lineno, (int) (linepos-line));
 181                         continue;
 182                 }
 183
 184                 if (strcasecmp(variable, "udev_root") == 0) {
 185                         strlcpy(udev_root, value, sizeof(udev_root));
 186                         remove_trailing_char(udev_root, '/');
 187                         continue;
 188                 }
 189
 190                 if (strcasecmp(variable, "udev_db") == 0) {
 191                         strlcpy(udev_db_path, value, sizeof(udev_db_path));
 192                         remove_trailing_char(udev_db_path, '/');
 193                         continue;
 194                 }
 195
 196                 if (strcasecmp(variable, "udev_rules") == 0) {
 197                         strlcpy(udev_rules_filename, value, sizeof(udev_rules_filename));
 198                         remove_trailing_char(udev_rules_filename, '/');
 199                         continue;
 200                 }
 201
 202                 if (strcasecmp(variable, "udev_log") == 0) {
 203                         udev_log_priority = log_priority(value);
 204                         continue;
 205                 }
 206         }
 207
 208         file_unmap(buf, bufsize);
 209         return retval;
 210 }
 211
 212 void udev_init_config(void)
 213 {
 214         const char *env;
 215
 216         strcpy(udev_root, UDEV_ROOT);
 217         strcpy(udev_db_path, UDEV_DB);
 218         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
 219         strcpy(udev_rules_filename, UDEV_RULES_FILE);
 220         udev_log_priority = LOG_ERR;
 221         udev_run = 1;
 222         udev_dev_d = 1;
 223         udev_hotplug_d = 1;
 224         sysfs_get_mnt_path(sysfs_path, sizeof(sysfs_path));
 225
 226         /* disable RUN key execution */
 227         env = getenv("UDEV_RUN");
 228         if (env && !string_is_true(env))
 229                 udev_run = 0;
 230
 231         env = getenv("UDEV_NO_DEVD");
 232         if (env && string_is_true(env))
 233                 udev_dev_d = 0;
 234
 235         env = getenv("UDEV_NO_HOTPLUGD");
 236         if (env && string_is_true(env))
 237                 udev_hotplug_d = 0;
 238
 239         env = getenv("UDEV_CONFIG_FILE");
 240         if (env) {
 241                 strlcpy(udev_config_filename, env, sizeof(udev_config_filename));
 242                 remove_trailing_char(udev_config_filename, '/');
 243         }
 244
 245         parse_config_file();
 246
 247         env = getenv("UDEV_LOG");
 248         if (env)
 249                 udev_log_priority = log_priority(env);
 250
 251         dbg("sysfs_path='%s'", sysfs_path);
 252         dbg("UDEV_CONFIG_FILE='%s'", udev_config_filename);
 253         dbg("udev_root='%s'", udev_root);
 254         dbg("udev_db='%s'", udev_db_path);
 255         dbg("udev_rules='%s'", udev_rules_filename);
 256         dbg("udev_log=%d", udev_log_priority);
 257 }