1 /* 2 * services/outbound_list.h - keep list of outbound serviced queries. 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains functions to help a module keep track of the 40 * queries it has outstanding to authoritative servers. 41 */ 42 #ifndef SERVICES_OUTBOUND_LIST_H 43 #define SERVICES_OUTBOUND_LIST_H 44 struct outbound_entry; 45 struct serviced_query; 46 struct module_qstate; 47 48 /** 49 * The outbound list. This structure is part of the module specific query 50 * state. 51 */ 52 struct outbound_list { 53 /** The linked list of outbound query entries. */ 54 struct outbound_entry* first; 55 }; 56 57 /** 58 * Outbound list entry. A serviced query sent by a module processing the 59 * query from the qstate. Double linked list to aid removal. 60 */ 61 struct outbound_entry { 62 /** next in list */ 63 struct outbound_entry* next; 64 /** prev in list */ 65 struct outbound_entry* prev; 66 /** The query that was sent out */ 67 struct serviced_query* qsent; 68 /** the module query state that sent it */ 69 struct module_qstate* qstate; 70 }; 71 72 /** 73 * Init the user allocated outbound list structure 74 * @param list: the list structure. 75 */ 76 void outbound_list_init(struct outbound_list* list); 77 78 /** 79 * Clear the user owner outbound list structure. 80 * Deletes serviced queries. 81 * @param list: the list structure. It is cleared, but the list struct itself 82 * is callers responsibility to delete. 83 */ 84 void outbound_list_clear(struct outbound_list* list); 85 86 /** 87 * Insert new entry into the list. Caller must allocate the entry with malloc. 88 * qstate and qsent are set by caller. 89 * @param list: the list to add to. 90 * @param e: entry to add, it is only half initialised at call start, fully 91 * initialised at call end. 92 */ 93 void outbound_list_insert(struct outbound_list* list, 94 struct outbound_entry* e); 95 96 /** 97 * Remove an entry from the list, and deletes it. 98 * Deletes serviced query in the entry. 99 * @param list: the list to remove from. 100 * @param e: the entry to remove. 101 */ 102 void outbound_list_remove(struct outbound_list* list, 103 struct outbound_entry* e); 104 105 #endif /* SERVICES_OUTBOUND_LIST_H */ 106