sys/modules/example/example.c

   1 /*      $NetBSD: example.c,v 1.4 2009/01/14 00:53:44 haad Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  26  * POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __KERNEL_RCSID(0, "$NetBSD: example.c,v 1.4 2009/01/14 00:53:44 haad Exp $");
  31
  32 #include <sys/param.h>
  33 #include <sys/kernel.h>
  34 #include <sys/module.h>
  35
  36 /*
  37  * Last parameter of MODULE macro is name of modules on
  38  * which defined module depends.
  39  */
  40
  41 MODULE(MODULE_CLASS_MISC, example, NULL);
  42
  43 static
  44 void
  45 handle_props(prop_dictionary_t props)
  46 {
  47         prop_string_t str;
  48
  49         if (props != NULL) {
  50                 str = prop_dictionary_get(props, "msg");
  51         } else {
  52                 str = NULL;
  53         }
  54         if (str == NULL)
  55                 printf("The 'msg' property was not given.\n");
  56         else if (prop_object_type(str) != PROP_TYPE_STRING)
  57                 printf("The 'msg' property is not a string.\n");
  58         else {
  59                 const char *msg = prop_string_cstring_nocopy(str);
  60                 if (msg == NULL)
  61                         printf("Failed to process the 'msg' property.\n");
  62                 else
  63                         printf("The 'msg' property is: %s\n", msg);
  64         }
  65 }
  66
  67 static int
  68 example_modcmd(modcmd_t cmd, void *arg)
  69 {
  70
  71         switch (cmd) {
  72         case MODULE_CMD_INIT:
  73                 printf("Example module loaded.\n");
  74                 handle_props(arg);
  75                 break;
  76
  77         case MODULE_CMD_FINI:
  78                 printf("Example module unloaded.\n");
  79                 break;
  80
  81         case MODULE_CMD_STAT:
  82                 printf("Example module status queried.\n");
  83                 return ENOTTY;
  84
  85         default:
  86                 return ENOTTY;
  87         }
  88
  89         return 0;
  90 }