2 * SPDX-License-Identifier: BSD-2-Clause-NetBSD
4 * Copyright (c) 2000 Andrzej Bialecki <abial@freebsd.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <sys/types.h>
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/module.h>
35 #include <sys/sysctl.h>
36 #include <sys/kernel.h>
39 /* Some example data */
42 static char *c = "hi there from dyn_sysctl";
43 static struct sysctl_oid *a_root, *a_root1, *b_root;
44 static struct sysctl_ctx_list clist, clist1, clist2;
47 sysctl_dyn_sysctl_test(SYSCTL_HANDLER_ARGS)
49 char *buf = "let's produce some text...";
51 return (sysctl_handle_string(oidp, buf, strlen(buf), req));
55 * The function called at load/unload.
58 load(module_t mod, int cmd, void *arg)
65 /* Initialize the contexts */
66 printf("Initializing contexts and creating subtrees.\n\n");
67 sysctl_ctx_init(&clist);
68 sysctl_ctx_init(&clist1);
69 sysctl_ctx_init(&clist2);
71 * Create two partially overlapping subtrees, belonging
72 * to different contexts.
74 printf("TREE ROOT NAME\n");
75 a_root = SYSCTL_ADD_NODE(&clist,
76 SYSCTL_STATIC_CHILDREN(/* top of sysctl tree */),
77 OID_AUTO, "dyn_sysctl", CTLFLAG_RW, 0,
78 "dyn_sysctl root node");
79 a_root = SYSCTL_ADD_NODE(&clist1,
80 SYSCTL_STATIC_CHILDREN(/* top of sysctl tree */),
81 OID_AUTO, "dyn_sysctl", CTLFLAG_RW, 0,
82 "dyn_sysctl root node");
84 printf("SYSCTL_ADD_NODE failed!\n");
87 SYSCTL_ADD_LONG(&clist, SYSCTL_CHILDREN(a_root),
88 OID_AUTO, "long_a", CTLFLAG_RW, &a, "just to try");
89 SYSCTL_ADD_INT(&clist, SYSCTL_CHILDREN(a_root),
90 OID_AUTO, "int_b", CTLFLAG_RW, &b, 0, "just to try 1");
91 a_root1 = SYSCTL_ADD_NODE(&clist, SYSCTL_CHILDREN(a_root),
92 OID_AUTO, "nextlevel", CTLFLAG_RD, 0, "one level down");
93 SYSCTL_ADD_STRING(&clist, SYSCTL_CHILDREN(a_root1),
94 OID_AUTO, "string_c", CTLFLAG_RD, c, 0, "just to try 2");
95 printf("1. (%p) / dyn_sysctl\n", &clist);
97 /* Add a subtree under already existing category */
98 a_root1 = SYSCTL_ADD_NODE(&clist, SYSCTL_STATIC_CHILDREN(_kern),
99 OID_AUTO, "dyn_sysctl", CTLFLAG_RW, 0, "dyn_sysctl root node");
100 if (a_root1 == NULL) {
101 printf("SYSCTL_ADD_NODE failed!\n");
104 SYSCTL_ADD_PROC(&clist, SYSCTL_CHILDREN(a_root1),
105 OID_AUTO, "procedure", CTLTYPE_STRING | CTLFLAG_RD,
106 NULL, 0, sysctl_dyn_sysctl_test, "A",
107 "I can be here, too");
108 printf(" (%p) /kern dyn_sysctl\n", &clist);
110 /* Overlap second tree with the first. */
111 b_root = SYSCTL_ADD_NODE(&clist1, SYSCTL_CHILDREN(a_root),
112 OID_AUTO, "nextlevel", CTLFLAG_RD, 0, "one level down");
113 SYSCTL_ADD_STRING(&clist1, SYSCTL_CHILDREN(b_root),
114 OID_AUTO, "string_c1", CTLFLAG_RD, c, 0, "just to try 2");
115 printf("2. (%p) / dyn_sysctl (overlapping #1)\n", &clist1);
118 * And now do something stupid. Connect another subtree to
120 * WARNING: this is an example of WRONG use of dynamic sysctls.
122 b_root=SYSCTL_ADD_NODE(&clist2, SYSCTL_CHILDREN(a_root1),
123 OID_AUTO, "bad", CTLFLAG_RW, 0, "dependent node");
124 SYSCTL_ADD_STRING(&clist2, SYSCTL_CHILDREN(b_root),
125 OID_AUTO, "string_c", CTLFLAG_RD, c, 0, "shouldn't panic");
126 printf("3. (%p) /kern/dyn_sysctl bad (WRONG!)\n", &clist2);
129 printf("1. Try to free ctx1 (%p): ", &clist);
130 if (sysctl_ctx_free(&clist) != 0)
131 printf("failed: expected. Need to remove ctx3 first.\n");
133 printf("HELP! sysctl_ctx_free(%p) succeeded. EXPECT PANIC!!!\n", &clist);
134 printf("2. Try to free ctx3 (%p): ", &clist2);
135 if (sysctl_ctx_free(&clist2) != 0) {
136 printf("sysctl_ctx_free(%p) failed!\n", &clist2);
137 /* Remove subtree forcefully... */
138 sysctl_remove_oid(b_root, 1, 1);
139 printf("sysctl_remove_oid(%p) succeeded\n", b_root);
142 printf("3. Try to free ctx1 (%p) again: ", &clist);
143 if (sysctl_ctx_free(&clist) != 0) {
144 printf("sysctl_ctx_free(%p) failed!\n", &clist);
145 /* Remove subtree forcefully... */
146 sysctl_remove_oid(a_root1, 1, 1);
147 printf("sysctl_remove_oid(%p) succeeded\n", a_root1);
150 printf("4. Try to free ctx2 (%p): ", &clist1);
151 if (sysctl_ctx_free(&clist1) != 0) {
152 printf("sysctl_ctx_free(%p) failed!\n", &clist1);
153 /* Remove subtree forcefully... */
154 sysctl_remove_oid(a_root, 1, 1);
165 static moduledata_t mod_data = {
171 DECLARE_MODULE(dyn_sysctl, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);