/*- * Copyright (c) 2000 Andrzej Bialecki * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: src/share/examples/kld/dyn_sysctl/dyn_sysctl.c,v 1.1.2.2 2002/03/27 20:45:11 abial Exp $ * $DragonFly: src/share/examples/kld/dyn_sysctl/dyn_sysctl.c,v 1.2 2003/06/17 04:36:57 dillon Exp $ */ #include #include #include #include #include #include /* Some example data */ static long a = 100; static int b = 200; static char *c = "hi there from dyn_sysctl"; static struct sysctl_oid *a_root, *a_root1, *b_root; static struct sysctl_ctx_list clist, clist1, clist2; static int sysctl_dyn_sysctl_test (SYSCTL_HANDLER_ARGS) { char *buf = "let's produce some text..."; return (sysctl_handle_string(oidp, buf, strlen(buf), req)); } /* * The function called at load/unload. */ static int load (module_t mod, int cmd, void *arg) { int error; error = 0; switch (cmd) { case MOD_LOAD : /* Initialize the contexts */ kprintf("Initializing contexts and creating subtrees.\n\n"); sysctl_ctx_init(&clist); sysctl_ctx_init(&clist1); sysctl_ctx_init(&clist2); /* * Create two partially overlapping subtrees, belonging * to different contexts. */ kprintf("TREE ROOT NAME\n"); a_root = SYSCTL_ADD_NODE(&clist, SYSCTL_STATIC_CHILDREN(/* top of sysctl tree */), OID_AUTO, "dyn_sysctl", CTLFLAG_RW, 0, "dyn_sysctl root node"); a_root = SYSCTL_ADD_NODE(&clist1, SYSCTL_STATIC_CHILDREN(/* top of sysctl tree */), OID_AUTO, "dyn_sysctl", CTLFLAG_RW, 0, "dyn_sysctl root node"); if(a_root == NULL) { kprintf("SYSCTL_ADD_NODE failed!\n"); return (EINVAL); } SYSCTL_ADD_LONG(&clist, SYSCTL_CHILDREN(a_root), OID_AUTO, "long_a", CTLFLAG_RW, &a, "just to try"); SYSCTL_ADD_INT(&clist, SYSCTL_CHILDREN(a_root), OID_AUTO, "int_b", CTLFLAG_RW, &b, 0, "just to try 1"); a_root1=SYSCTL_ADD_NODE(&clist, SYSCTL_CHILDREN(a_root), OID_AUTO, "nextlevel", CTLFLAG_RD, 0, "one level down"); SYSCTL_ADD_STRING(&clist, SYSCTL_CHILDREN(a_root1), OID_AUTO, "string_c", CTLFLAG_RD, c, 0, "just to try 2"); kprintf("1. (%p) / dyn_sysctl\n", &clist); /* Add a subtree under already existing category */ a_root1 = SYSCTL_ADD_NODE(&clist, SYSCTL_STATIC_CHILDREN(_kern), OID_AUTO, "dyn_sysctl", CTLFLAG_RW, 0, "dyn_sysctl root node"); if(a_root1 == NULL) { kprintf("SYSCTL_ADD_NODE failed!\n"); return (EINVAL); } SYSCTL_ADD_PROC(&clist, SYSCTL_CHILDREN(a_root1), OID_AUTO, "procedure", CTLFLAG_RD, 0, 0, sysctl_dyn_sysctl_test, "A", "I can be here, too"); kprintf(" (%p) /kern dyn_sysctl\n", &clist); /* Overlap second tree with the first. */ b_root = SYSCTL_ADD_NODE(&clist1, SYSCTL_CHILDREN(a_root), OID_AUTO, "nextlevel", CTLFLAG_RD, 0, "one level down"); SYSCTL_ADD_STRING(&clist1, SYSCTL_CHILDREN(b_root), OID_AUTO, "string_c1", CTLFLAG_RD, c, 0, "just to try 2"); kprintf("2. (%p) / dyn_sysctl (overlapping #1)\n", &clist1); /* * And now do something stupid. Connect another subtree to * dynamic oid. * WARNING: this is an example of WRONG use of dynamic sysctls. */ b_root=SYSCTL_ADD_NODE(&clist2, SYSCTL_CHILDREN(a_root1), OID_AUTO, "bad", CTLFLAG_RW, 0, "dependent node"); SYSCTL_ADD_STRING(&clist2, SYSCTL_CHILDREN(b_root), OID_AUTO, "string_c", CTLFLAG_RD, c, 0, "shouldn't panic"); kprintf("3. (%p) /kern/dyn_sysctl bad (WRONG!)\n", &clist2); break; case MOD_UNLOAD : kprintf("1. Try to free ctx1 (%p): ", &clist); if(sysctl_ctx_free(&clist)) kprintf("failed: expected. Need to remove ctx3 first.\n"); else kprintf("HELP! sysctl_ctx_free(%p) succeeded. EXPECT PANIC!!!\n", &clist); kprintf("2. Try to free ctx3 (%p): ", &clist2); if(sysctl_ctx_free(&clist2)) { kprintf("sysctl_ctx_free(%p) failed!\n", &clist2); /* Remove subtree forcefully... */ sysctl_remove_oid(b_root, 1, 1); kprintf("sysctl_remove_oid(%p) succeeded\n", b_root); } else kprintf("Ok\n"); kprintf("3. Try to free ctx1 (%p) again: ", &clist); if(sysctl_ctx_free(&clist)) { kprintf("sysctl_ctx_free(%p) failed!\n", &clist); /* Remove subtree forcefully... */ sysctl_remove_oid(a_root1, 1, 1); kprintf("sysctl_remove_oid(%p) succeeded\n", a_root1); } else kprintf("Ok\n"); kprintf("4. Try to free ctx2 (%p): ", &clist1); if(sysctl_ctx_free(&clist1)) { kprintf("sysctl_ctx_free(%p) failed!\n", &clist1); /* Remove subtree forcefully... */ sysctl_remove_oid(a_root, 1, 1); } else kprintf("Ok\n"); break; default : error = EINVAL; break; } return error; } static moduledata_t mod_data= { "dyn_sysctl", load, 0 }; DECLARE_MODULE(dyn_sysctl, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);