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