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_dev_d;
  48 int udev_hotplug_d;
  49
  50 static int string_is_true(const char *str)
  51 {
  52         if (strcasecmp(str, "true") == 0)
  53                 return 1;
  54         if (strcasecmp(str, "yes") == 0)
  55                 return 1;
  56         if (strcasecmp(str, "1") == 0)
  57                 return 1;
  58         return 0;
  59 }
  60
  61 static int log_priority(const char *priority)
  62 {
  63         char *endptr;
  64         int prio;
  65
  66         prio = strtol(priority, &endptr, 10);
  67         if (endptr[0] == '\0')
  68                 return prio;
  69         if (strncasecmp(priority, "err", 3) == 0)
  70                 return LOG_ERR;
  71         if (strcasecmp(priority, "info") == 0)
  72                 return LOG_INFO;
  73         if (strcasecmp(priority, "debug") == 0)
  74                 return LOG_DEBUG;
  75         if (string_is_true(priority))
  76                 return LOG_ERR;
  77
  78         return 0;
  79 }
  80
  81 static int get_key(char **line, char **key, char **value)
  82 {
  83         char *linepos;
  84         char *temp;
  85
  86         linepos = *line;
  87         if (!linepos)
  88                 return -1;
  89
  90         /* skip whitespace */
  91         while (isspace(linepos[0]))
  92                 linepos++;
  93
  94         /* get the key */
  95         *key = linepos;
  96         while (1) {
  97                 linepos++;
  98                 if (linepos[0] == '\0')
  99                         return -1;
 100                 if (isspace(linepos[0]))
 101                         break;
 102                 if (linepos[0] == '=')
 103                         break;
 104         }
 105
 106         /* terminate key */
 107         linepos[0] = '\0';
 108         linepos++;
 109
 110         /* skip whitespace */
 111         while (isspace(linepos[0]))
 112                 linepos++;
 113
 114         /* get the value*/
 115         if (linepos[0] == '"')
 116                 linepos++;
 117         else
 118                 return -1;
 119         *value = linepos;
 120
 121         temp = strchr(linepos, '"');
 122         if (!temp)
 123                 return -1;
 124         temp[0] = '\0';
 125
 126         return 0;
 127 }
 128
 129 static int parse_config_file(void)
 130 {
 131         char line[LINE_SIZE];
 132         char *bufline;
 133         char *linepos;
 134         char *variable;
 135         char *value;
 136         char *buf;
 137         size_t bufsize;
 138         size_t cur;
 139         size_t count;
 140         int lineno;
 141         int retval = 0;
 142
 143         if (file_map(udev_config_filename, &buf, &bufsize) != 0) {
 144                 err("can't open '%s' as config file", udev_config_filename);
 145                 return -ENODEV;
 146         }
 147
 148         /* loop through the whole file */
 149         lineno = 0;
 150         cur = 0;
 151         while (cur < bufsize) {
 152                 count = buf_get_line(buf, bufsize, cur);
 153                 bufline = &buf[cur];
 154                 cur += count+1;
 155                 lineno++;
 156
 157                 if (count >= sizeof(line)) {
 158                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
 159                         continue;
 160                 }
 161
 162                 /* eat the whitespace */
 163                 while ((count > 0) && isspace(bufline[0])) {
 164                         bufline++;
 165                         count--;
 166                 }
 167                 if (count == 0)
 168                         continue;
 169
 170                 /* see if this is a comment */
 171                 if (bufline[0] == COMMENT_CHARACTER)
 172                         continue;
 173
 174                 strlcpy(line, bufline, count+1);
 175
 176                 linepos = line;
 177                 retval = get_key(&linepos, &variable, &value);
 178                 if (retval != 0) {
 179                         err("error parsing %s, line %d:%d", udev_config_filename, lineno, (int) (linepos-line));
 180                         continue;
 181                 }
 182
 183                 if (strcasecmp(variable, "udev_root") == 0) {
 184                         strlcpy(udev_root, value, sizeof(udev_root));
 185                         remove_trailing_char(udev_root, '/');
 186                         continue;
 187                 }
 188
 189                 if (strcasecmp(variable, "udev_db") == 0) {
 190                         strlcpy(udev_db_path, value, sizeof(udev_db_path));
 191                         remove_trailing_char(udev_db_path, '/');
 192                         continue;
 193                 }
 194
 195                 if (strcasecmp(variable, "udev_rules") == 0) {
 196                         strlcpy(udev_rules_filename, value, sizeof(udev_rules_filename));
 197                         remove_trailing_char(udev_rules_filename, '/');
 198                         continue;
 199                 }
 200
 201                 if (strcasecmp(variable, "udev_log") == 0) {
 202                         udev_log_priority = log_priority(value);
 203                         continue;
 204                 }
 205         }
 206
 207         file_unmap(buf, bufsize);
 208         return retval;
 209 }
 210
 211 void udev_init_config(void)
 212 {
 213         const char *env;
 214
 215         strcpy(udev_root, UDEV_ROOT);
 216         strcpy(udev_db_path, UDEV_DB);
 217         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
 218         strcpy(udev_rules_filename, UDEV_RULES_FILE);
 219         udev_log_priority = LOG_ERR;
 220         udev_dev_d = 1;
 221         udev_hotplug_d = 1;
 222         sysfs_get_mnt_path(sysfs_path, sizeof(sysfs_path));
 223
 224         env = getenv("UDEV_NO_DEVD");
 225         if (env && string_is_true(env))
 226                 udev_dev_d = 0;
 227
 228         env = getenv("UDEV_NO_HOTPLUGD");
 229         if (env && string_is_true(env))
 230                 udev_hotplug_d = 0;
 231
 232         env = getenv("UDEV_CONFIG_FILE");
 233         if (env) {
 234                 strlcpy(udev_config_filename, env, sizeof(udev_config_filename));
 235                 remove_trailing_char(udev_config_filename, '/');
 236         }
 237
 238         parse_config_file();
 239
 240         env = getenv("UDEV_LOG");
 241         if (env)
 242                 udev_log_priority = log_priority(env);
 243
 244         dbg("sysfs_path='%s'", sysfs_path);
 245         dbg("UDEV_CONFIG_FILE='%s'", udev_config_filename);
 246         dbg("udev_root='%s'", udev_root);
 247         dbg("udev_db='%s'", udev_db_path);
 248         dbg("udev_rules='%s'", udev_rules_filename);
 249         dbg("udev_log=%d", udev_log_priority);
 250 }