udev.c

   1 /*
   2  * udev.c
   3  *
   4  * Userspace devfs
   5  *
   6  * Copyright (C) 2003 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
  32 #include "udev.h"
  33 #include "udev_version.h"
  34 #include "namedev.h"
  35 #include "udevdb.h"
  36 #include "libsysfs/libsysfs.h"
  37
  38 /* global variables */
  39 char **main_argv;
  40 char **main_envp;
  41
  42 static inline char *get_action(void)
  43 {
  44         char *action;
  45
  46         action = getenv("ACTION");
  47         return action;
  48 }
  49
  50 static inline char *get_devpath(void)
  51 {
  52         char *devpath;
  53
  54         devpath = getenv("DEVPATH");
  55         return devpath;
  56 }
  57
  58 static inline char *get_seqnum(void)
  59 {
  60         char *seqnum;
  61
  62         seqnum = getenv("SEQNUM");
  63         return seqnum;
  64 }
  65
  66 int main(int argc, char **argv, char **envp)
  67 {
  68         char *action;
  69         char *devpath;
  70         char *subsystem;
  71         int retval = -EINVAL;
  72
  73         main_argv = argv;
  74         main_envp = envp;
  75
  76         dbg("version %s", UDEV_VERSION);
  77
  78         if (argc != 2) {
  79                 dbg ("unknown number of arguments");
  80                 goto exit;
  81         }
  82
  83         subsystem = argv[1];
  84
  85         devpath = get_devpath();
  86         if (!devpath) {
  87                 dbg ("no devpath?");
  88                 goto exit;
  89         }
  90         dbg("looking at '%s'", devpath);
  91
  92         /* we only care about class devices and block stuff */
  93         if (!strstr(devpath, "class") &&
  94             !strstr(devpath, "block")) {
  95                 dbg("not a block or class device");
  96                 goto exit;
  97         }
  98
  99         /* but we don't care about net class devices */
 100         if (strcmp(subsystem, "net") == 0) {
 101                 dbg("don't care about net devices");
 102                 goto exit;
 103         }
 104
 105         action = get_action();
 106         if (!action) {
 107                 dbg ("no action?");
 108                 goto exit;
 109         }
 110
 111         /* initialize our configuration */
 112         udev_init_config();
 113
 114         /* initialize udev database */
 115         retval = udevdb_init(UDEVDB_DEFAULT);
 116         if (retval != 0) {
 117                 dbg("unable to initialize database");
 118                 goto exit;
 119         }
 120
 121         /* initialize the naming deamon */
 122         namedev_init();
 123
 124         if (strcmp(action, "add") == 0)
 125                 retval = udev_add_device(devpath, subsystem);
 126
 127         else if (strcmp(action, "remove") == 0)
 128                 retval = udev_remove_device(devpath, subsystem);
 129
 130         else {
 131                 dbg("unknown action '%s'", action);
 132                 retval = -EINVAL;
 133         }
 134         udevdb_exit();
 135
 136 exit:
 137         return retval;
 138 }