udev_config.c

   1 /*
   2  * Copyright (C) 2003-2004 Greg Kroah-Hartman <greg@kroah.com>
   3  * Copyright (C) 2004-2005 Kay Sievers <kay.sievers@vrfy.org>
   4  *
   5  *      This program is free software; you can redistribute it and/or modify it
   6  *      under the terms of the GNU General Public License as published by the
   7  *      Free Software Foundation version 2 of the License.
   8  *
   9  *      This program is distributed in the hope that it will be useful, but
  10  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *      General Public License for more details.
  13  *
  14  *      You should have received a copy of the GNU General Public License along
  15  *      with this program; if not, write to the Free Software Foundation, Inc.,
  16  *      51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  *
  18  */
  19
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <stdio.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <ctype.h>
  27 #include <syslog.h>
  28
  29 #include "udev.h"
  30
  31 /* global variables */
  32 char udev_root[PATH_SIZE];
  33 char udev_config_filename[PATH_SIZE];
  34 char udev_rules_dir[PATH_SIZE];
  35 int udev_log_priority;
  36 int udev_run;
  37
  38 static int get_key(char **line, char **key, char **value)
  39 {
  40         char *linepos;
  41         char *temp;
  42
  43         linepos = *line;
  44         if (!linepos)
  45                 return -1;
  46
  47         /* skip whitespace */
  48         while (isspace(linepos[0]))
  49                 linepos++;
  50
  51         /* get the key */
  52         *key = linepos;
  53         while (1) {
  54                 linepos++;
  55                 if (linepos[0] == '\0')
  56                         return -1;
  57                 if (isspace(linepos[0]))
  58                         break;
  59                 if (linepos[0] == '=')
  60                         break;
  61         }
  62
  63         /* terminate key */
  64         linepos[0] = '\0';
  65         linepos++;
  66
  67         /* skip whitespace */
  68         while (isspace(linepos[0]))
  69                 linepos++;
  70
  71         /* get the value*/
  72         if (linepos[0] == '"')
  73                 linepos++;
  74         else
  75                 return -1;
  76         *value = linepos;
  77
  78         temp = strchr(linepos, '"');
  79         if (!temp)
  80                 return -1;
  81         temp[0] = '\0';
  82
  83         return 0;
  84 }
  85
  86 static int parse_config_file(void)
  87 {
  88         char line[LINE_SIZE];
  89         char *bufline;
  90         char *linepos;
  91         char *variable;
  92         char *value;
  93         char *buf;
  94         size_t bufsize;
  95         size_t cur;
  96         size_t count;
  97         int lineno;
  98         int retval = 0;
  99
 100         if (file_map(udev_config_filename, &buf, &bufsize) != 0) {
 101                 err("can't open '%s' as config file: %s", udev_config_filename, strerror(errno));
 102                 return -ENODEV;
 103         }
 104
 105         /* loop through the whole file */
 106         lineno = 0;
 107         cur = 0;
 108         while (cur < bufsize) {
 109                 count = buf_get_line(buf, bufsize, cur);
 110                 bufline = &buf[cur];
 111                 cur += count+1;
 112                 lineno++;
 113
 114                 if (count >= sizeof(line)) {
 115                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
 116                         continue;
 117                 }
 118
 119                 /* eat the whitespace */
 120                 while ((count > 0) && isspace(bufline[0])) {
 121                         bufline++;
 122                         count--;
 123                 }
 124                 if (count == 0)
 125                         continue;
 126
 127                 /* see if this is a comment */
 128                 if (bufline[0] == COMMENT_CHARACTER)
 129                         continue;
 130
 131                 memcpy(line, bufline, count);
 132                 line[count] = '\0';
 133
 134                 linepos = line;
 135                 retval = get_key(&linepos, &variable, &value);
 136                 if (retval != 0) {
 137                         err("error parsing %s, line %d:%d", udev_config_filename, lineno, (int)(linepos-line));
 138                         continue;
 139                 }
 140
 141                 if (strcasecmp(variable, "udev_root") == 0) {
 142                         strlcpy(udev_root, value, sizeof(udev_root));
 143                         remove_trailing_chars(udev_root, '/');
 144                         continue;
 145                 }
 146
 147                 if (strcasecmp(variable, "udev_rules") == 0) {
 148                         strlcpy(udev_rules_dir, value, sizeof(udev_rules_dir));
 149                         remove_trailing_chars(udev_rules_dir, '/');
 150                         continue;
 151                 }
 152
 153                 if (strcasecmp(variable, "udev_log") == 0) {
 154                         udev_log_priority = log_priority(value);
 155                         continue;
 156                 }
 157         }
 158
 159         file_unmap(buf, bufsize);
 160         return retval;
 161 }
 162
 163 void udev_config_init(void)
 164 {
 165         const char *env;
 166
 167         strcpy(udev_root, UDEV_ROOT);
 168         strcpy(udev_config_filename, UDEV_CONFIG_FILE);
 169         strcpy(udev_rules_dir, UDEV_RULES_DIR);
 170         udev_log_priority = LOG_ERR;
 171         udev_run = 1;
 172
 173         /* disable RUN key execution */
 174         env = getenv("UDEV_RUN");
 175         if (env && !string_is_true(env))
 176                 udev_run = 0;
 177
 178         env = getenv("UDEV_CONFIG_FILE");
 179         if (env) {
 180                 strlcpy(udev_config_filename, env, sizeof(udev_config_filename));
 181                 remove_trailing_chars(udev_config_filename, '/');
 182         }
 183
 184         parse_config_file();
 185
 186         env = getenv("UDEV_ROOT");
 187         if (env) {
 188                 strlcpy(udev_root, env, sizeof(udev_root));
 189                 remove_trailing_chars(udev_root, '/');
 190         }
 191
 192         env = getenv("UDEV_LOG");
 193         if (env)
 194                 udev_log_priority = log_priority(env);
 195
 196         dbg("UDEV_CONFIG_FILE='%s'", udev_config_filename);
 197         dbg("udev_root='%s'", udev_root);
 198         dbg("udev_rules='%s'", udev_rules_dir);
 199         dbg("udev_log=%d", udev_log_priority);
 200 }