xref: /openbmc/linux/samples/kdb/kdb_hello.c (revision 588b48ca)
1 /*
2  * Created by: Jason Wessel <jason.wessel@windriver.com>
3  *
4  * Copyright (c) 2010 Wind River Systems, Inc.  All Rights Reserved.
5  *
6  * This file is licensed under the terms of the GNU General Public
7  * License version 2. This program is licensed "as is" without any
8  * warranty of any kind, whether express or implied.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/kdb.h>
13 
14 /*
15  * All kdb shell command call backs receive argc and argv, where
16  * argv[0] is the command the end user typed
17  */
18 static int kdb_hello_cmd(int argc, const char **argv)
19 {
20 	if (argc > 1)
21 		return KDB_ARGCOUNT;
22 
23 	if (argc)
24 		kdb_printf("Hello %s.\n", argv[1]);
25 	else
26 		kdb_printf("Hello world!\n");
27 
28 	return 0;
29 }
30 
31 
32 static int __init kdb_hello_cmd_init(void)
33 {
34 	/*
35 	 * Registration of a dynamically added kdb command is done with
36 	 * kdb_register() with the arguments being:
37 	 *   1: The name of the shell command
38 	 *   2: The function that processes the command
39 	 *   3: Description of the usage of any arguments
40 	 *   4: Descriptive text when you run help
41 	 *   5: Number of characters to complete the command
42 	 *      0 == type the whole command
43 	 *      1 == match both "g" and "go" for example
44 	 */
45 	kdb_register("hello", kdb_hello_cmd, "[string]",
46 		     "Say Hello World or Hello [string]", 0);
47 	return 0;
48 }
49 
50 static void __exit kdb_hello_cmd_exit(void)
51 {
52 	kdb_unregister("hello");
53 }
54 
55 module_init(kdb_hello_cmd_init);
56 module_exit(kdb_hello_cmd_exit);
57 
58 MODULE_AUTHOR("WindRiver");
59 MODULE_DESCRIPTION("KDB example to add a hello command");
60 MODULE_LICENSE("GPL");
61