udev_config.c

   1 /*
   2  * udev_config.c
   3  *
   4  * Copyright (C) 2003,2004 Greg Kroah-Hartman <greg@kroah.com>
   5  * Copyright (C) 2004, 2005 Kay Sievers <kay.sievers@vrfy.org>
   6  *
   7  *      This program is free software; you can redistribute it and/or modify it
   8  *      under the terms of the GNU General Public License as published by the
   9  *      Free Software Foundation version 2 of the License.
  10  *
  11  *      This program is distributed in the hope that it will be useful, but
  12  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *      General Public License for more details.
  15  *
  16  *      You should have received a copy of the GNU General Public License along
  17  *      with this program; if not, write to the Free Software Foundation, Inc.,
  18  *      675 Mass Ave, Cambridge, MA 02139, USA.
  19  *
  20  */
  21
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <stdio.h>
  25 #include <fcntl.h>
  26 #include <unistd.h>
  27 #include <errno.h>
  28 #include <ctype.h>
  29 #include <syslog.h>
  30
  31 #include "libsysfs/sysfs/libsysfs.h"
  32 #include "udev_libc_wrapper.h"
  33 #include "udev.h"
  34 #include "udev_utils.h"
  35 #include "udev_version.h"
  36 #include "logging.h"
  37
  38 /* global variables */
  39 char sysfs_path[PATH_SIZE];
  40 char udev_root[PATH_SIZE];
  41 char udev_db_path[PATH_SIZE];
  42 char udev_config_filename[PATH_SIZE];
  43 char udev_rules_filename[PATH_SIZE];
  44 int udev_log_priority;
  45 int udev_run;
  46
  47 static int get_key(char **line, char **key, char **value)
  48 {
  49         char *linepos;
  50         char *temp;
  51
  52         linepos = *line;
  53         if (!linepos)
  54                 return -1;
  55
  56         /* skip whitespace */
  57         while (isspace(linepos[0]))
  58                 linepos++;
  59
  60         /* get the key */
  61         *key = linepos;
  62         while (1) {
  63                 linepos++;
  64                 if (linepos[0] == '\0')
  65                         return -1;
  66                 if (isspace(linepos[0]))
  67                         break;
  68                 if (linepos[0] == '=')
  69                         break;
  70         }
  71
  72         /* terminate key */
  73         linepos[0] = '\0';
  74         linepos++;
  75
  76         /* skip whitespace */
  77         while (isspace(linepos[0]))
  78                 linepos++;
  79
  80         /* get the value*/
  81         if (linepos[0] == '"')
  82                 linepos++;
  83         else
  84                 return -1;
  85         *value = linepos;
  86
  87         temp = strchr(linepos, '"');
  88         if (!temp)
  89                 return -1;
  90         temp[0] = '\0';
  91
  92         return 0;
  93 }
  94
  95 static int parse_config_file(void)
  96 {
  97         char line[LINE_SIZE];
  98         char *bufline;
  99         char *linepos;
 100         char *variable;
 101         char *value;
 102         char *buf;
 103         size_t bufsize;
 104         size_t cur;
 105         size_t count;
 106         int lineno;
 107         int retval = 0;
 108
 109         if (file_map(udev_config_filename, &buf, &bufsize) != 0) {
 110                 err("can't open '%s' as config file", udev_config_filename);
 111                 return -ENODEV;
 112         }
 113
 114         /* loop through the whole file */
 115         lineno = 0;
 116         cur = 0;
 117         while (cur < bufsize) {
 118                 count = buf_get_line(buf, bufsize, cur);
 119                 bufline = &buf[cur];
 120                 cur += count+1;
 121                 lineno++;
 122
 123                 if (count >= sizeof(line)) {
 124                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
 125                         continue;
 126                 }
 127
 128                 /* eat the whitespace */
 129                 while ((count > 0) && isspace(bufline[0])) {
 130                         bufline++;
 131                         count--;
 132                 }
 133                 if (count == 0)
 134                         continue;
 135
 136                 /* see if this is a comment */
 137                 if (bufline[0] == COMMENT_CHARACTER)
 138                         continue;
 139
 140                 memcpy(line, bufline, count);
 141                 line[count] = '\0';
 142
 143                 linepos = line;
 144                 retval = get_key(&linepos, &variable, &value);
 145                 if (retval != 0) {
 146                         err("error parsing %s, line %d:%d", udev_config_filename, lineno, (int) (linepos-line));
 147                         continue;
 148                 }
 149
 150                 if (strcasecmp(variable, "udev_root") == 0) {
 151                         strlcpy(udev_root, value, sizeof(udev_root));
 152                         remove_trailing_chars(udev_root, '/');
 153                         continue;
 154                 }
 155
 156                 if (strcasecmp(variable, "udev_db") == 0) {
 157                         strlcpy(udev_db_path, value, sizeof(udev_db_path));
 158                         remove_trailing_chars(udev_db_path, '/');
 159                         continue;
 160                 }
 161
 162                 if (strcasecmp(variable, "udev_rules") == 0) {
 163                         strlcpy(udev_rules_filename, value, sizeof(udev_rules_filename));
 164                         remove_trailing_chars(udev_rules_filename, '/');
 165                         continue;
 166                 }
 167
 168                 if (strcasecmp(variable, "udev_log") == 0) {
 169                         udev_log_priority = log_priority(value);
 170                         continue;
 171                 }
 172         }
 173
 174         file_unmap(buf, bufsize);
 175         return retval;
 176 }
 177
 178 void udev_init_config(void)
 179 {
 180         const char *env;
 181
 182         strcpy(udev_root, UDEV_ROOT);
 183         strcpy(udev_db_path, UDEV_DB);
 184         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
 185         strcpy(udev_rules_filename, UDEV_RULES_FILE);
 186         udev_log_priority = LOG_ERR;
 187         udev_run = 1;
 188         sysfs_get_mnt_path(sysfs_path, sizeof(sysfs_path));
 189
 190         /* disable RUN key execution */
 191         env = getenv("UDEV_RUN");
 192         if (env && !string_is_true(env))
 193                 udev_run = 0;
 194
 195         env = getenv("UDEV_CONFIG_FILE");
 196         if (env) {
 197                 strlcpy(udev_config_filename, env, sizeof(udev_config_filename));
 198                 remove_trailing_chars(udev_config_filename, '/');
 199         }
 200
 201         parse_config_file();
 202
 203         env = getenv("UDEV_LOG");
 204         if (env)
 205                 udev_log_priority = log_priority(env);
 206
 207         dbg("sysfs_path='%s'", sysfs_path);
 208         dbg("UDEV_CONFIG_FILE='%s'", udev_config_filename);
 209         dbg("udev_root='%s'", udev_root);
 210         dbg("udev_db='%s'", udev_db_path);
 211         dbg("udev_rules='%s'", udev_rules_filename);
 212         dbg("udev_log=%d", udev_log_priority);
 213 }