diff options
Diffstat (limited to 'common/memory.c')
| -rw-r--r-- | common/memory.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/common/memory.c b/common/memory.c new file mode 100644 index 0000000..0e74159 --- /dev/null +++ b/common/memory.c @@ -0,0 +1,154 @@ +/* memory.c + + Memory-resident database... */ + +/* + * Copyright (c) 2004,2007,2009 by Internet Systems Consortium, Inc. ("ISC") + * Copyright (c) 1995-2003 by Internet Software Consortium + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT + * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + * Internet Systems Consortium, Inc. + * 950 Charter Street + * Redwood City, CA 94063 + * <info@isc.org> + * https://www.isc.org/ + * + * This software has been written for Internet Systems Consortium + * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc. + * To learn more about Internet Systems Consortium, see + * ``https://www.isc.org/''. To learn more about Vixie Enterprises, + * see ``http://www.vix.com''. To learn more about Nominum, Inc., see + * ``http://www.nominum.com''. + */ + +#include "dhcpd.h" + +struct group *root_group; +group_hash_t *group_name_hash; +int (*group_write_hook) (struct group_object *); + +isc_result_t delete_group (struct group_object *group, int writep) +{ + struct group_object *d; + + /* The group should exist and be hashed - if not, it's invalid. */ + if (group_name_hash) { + d = (struct group_object *)0; + group_hash_lookup (&d, group_name_hash, group -> name, + strlen (group -> name), MDL); + } else + return DHCP_R_INVALIDARG; + if (!d) + return DHCP_R_INVALIDARG; + + /* Also not okay to delete a group that's not the one in + the hash table. */ + if (d != group) + return DHCP_R_INVALIDARG; + + /* If it's dynamic, and we're deleting it, we can just blow away the + hash table entry. */ + if ((group -> flags & GROUP_OBJECT_DYNAMIC) && + !(group -> flags & GROUP_OBJECT_STATIC)) { + group_hash_delete (group_name_hash, + group -> name, strlen (group -> name), MDL); + } else { + group -> flags |= GROUP_OBJECT_DELETED; + if (group -> group) + group_dereference (&group -> group, MDL); + } + + /* Store the group declaration in the lease file. */ + if (writep && group_write_hook) { + if (!(*group_write_hook) (group)) + return ISC_R_IOERROR; + } + return ISC_R_SUCCESS; +} + +isc_result_t supersede_group (struct group_object *group, int writep) +{ + struct group_object *t; + + /* Register the group in the group name hash table, + so we can look it up later. */ + if (group_name_hash) { + t = (struct group_object *)0; + group_hash_lookup (&t, group_name_hash, + group -> name, + strlen (group -> name), MDL); + if (t && t != group) { + /* If this isn't a dynamic entry, then we need to flag + the replacement as not dynamic either - otherwise, + if the dynamic entry is deleted later, the static + entry will come back next time the server is stopped + and restarted. */ + if (!(t -> flags & GROUP_OBJECT_DYNAMIC)) + group -> flags |= GROUP_OBJECT_STATIC; + + /* Delete the old object if it hasn't already been + deleted. If it has already been deleted, get rid of + the hash table entry. This is a legitimate + situation - a deleted static object needs to be kept + around so we remember it's deleted. */ + if (!(t -> flags & GROUP_OBJECT_DELETED)) + delete_group (t, 0); + else { + group_hash_delete (group_name_hash, + group -> name, + strlen (group -> name), + MDL); + group_object_dereference (&t, MDL); + } + } + } else { + group_new_hash(&group_name_hash, GROUP_HASH_SIZE, MDL); + t = (struct group_object *)0; + } + + /* Add the group to the group name hash if it's not + already there, and also thread it into the list of + dynamic groups if appropriate. */ + if (!t) { + group_hash_add (group_name_hash, group -> name, + strlen (group -> name), group, MDL); + } + + /* Store the group declaration in the lease file. */ + if (writep && group_write_hook) { + if (!(*group_write_hook) (group)) + return ISC_R_IOERROR; + } + return ISC_R_SUCCESS; +} + +int clone_group (struct group **gp, struct group *group, + const char *file, int line) +{ + struct group *g = (struct group *)0; + + /* Normally gp should contain the null pointer, but for convenience + it's permissible to clone a group into itself. */ + if (*gp && *gp != group) + return 0; + if (!group_allocate (&g, file, line)) + return 0; + if (group == *gp) + *gp = (struct group *)0; + group_reference (gp, g, file, line); + g -> authoritative = group -> authoritative; + group_reference (&g -> next, group, file, line); + group_dereference (&g, file, line); + return 1; +} |