xref: /netbsd-src/sys/modules/examples/ddbping/ddbping.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: ddbping.c,v 1.2 2021/02/23 07:13:53 mrg Exp $ */
2 /*
3  * Copyright (c) 2020 Valery Ushakov
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 /*
28  * Example of a kernel module that registers DDB commands.
29  */
30 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: ddbping.c,v 1.2 2021/02/23 07:13:53 mrg Exp $");
32 
33 #include <sys/param.h>
34 #include <sys/module.h>
35 
36 #include <ddb/ddb.h>
37 
38 
39 static unsigned int ping_count;
40 static unsigned int ping_count_modif;
41 static unsigned int ping_count_addr;
42 static unsigned int ping_count_count;
43 
44 static void
45 db_ping(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
46 {
47 	db_printf("pong");
48 	++ping_count;
49 
50 	if (modif != NULL && *modif != '\0') {
51 		db_printf("/%s", modif);
52 		++ping_count_modif;
53 	}
54 
55 	if (have_addr) {
56 		db_printf(" 0x%zx", (size_t)addr);
57 		++ping_count_addr;
58 	}
59 
60 	if (count > 0) {
61 		db_printf(", 0t%zu", (size_t)count);
62 		++ping_count_count;
63 	}
64 
65 	db_printf("\n");
66 }
67 
68 
69 static void
70 db_show_ping(db_expr_t addr, bool have_addr, db_expr_t count, const char *modif)
71 {
72 	db_printf("total\t\t%u\n", ping_count);
73 	db_printf("with modifiers\t%u\n", ping_count_modif);
74 	db_printf("with address\t%u\n", ping_count_addr);
75 	db_printf("with count\t%u\n", ping_count_count);
76 }
77 
78 static const struct db_command db_ping_base_tbl[] = {
79 	{ DDB_ADD_CMD("ping", db_ping, 0,
80 		      "Example command",
81 		      NULL, NULL) },
82 	{ DDB_END_CMD },
83 };
84 
85 static const struct db_command db_ping_show_tbl[] = {
86 	{ DDB_ADD_CMD("ping", db_show_ping, 0,
87 		      "Example command stats",
88 		      NULL, NULL) },
89 	{ DDB_END_CMD },
90 };
91 
92 
93 MODULE(MODULE_CLASS_MISC, ddbping, NULL);
94 
95 static int
96 ddbping_modcmd(modcmd_t cmd, void *arg __unused)
97 {
98 	switch (cmd) {
99 	case MODULE_CMD_INIT:
100 		db_register_tbl(DDB_BASE_CMD, db_ping_base_tbl);
101 		db_register_tbl(DDB_SHOW_CMD, db_ping_show_tbl);
102 		break;
103 
104 	case MODULE_CMD_FINI:
105 		db_unregister_tbl(DDB_BASE_CMD, db_ping_base_tbl);
106 		db_unregister_tbl(DDB_SHOW_CMD, db_ping_show_tbl);
107 		break;
108 
109 	case MODULE_CMD_STAT:	/* FALLTHROUGH */
110 	default:
111 		return ENOTTY;
112 	}
113 
114 	return 0;
115 }
116