1 /*- 2 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/ 3 * Authors: Doug Rabson <dfr@rabson.org> 4 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org> 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 AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #ifndef _RPC_REPLAY_H 31 #define _RPC_REPLAY_H 32 33 enum replay_state { 34 RS_NEW, /* new request - caller should execute */ 35 RS_DONE, /* request was executed and reply sent */ 36 RS_INPROGRESS, /* request is being executed now */ 37 RS_ERROR /* allocation or other failure */ 38 }; 39 40 struct replay_cache; 41 42 /* 43 * Create a new replay cache. 44 */ 45 struct replay_cache *replay_newcache(size_t); 46 47 /* 48 * Set the replay cache size. 49 */ 50 void replay_setsize(struct replay_cache *, size_t); 51 52 /* 53 * Free a replay cache. Caller must ensure that no cache entries are 54 * in-progress. 55 */ 56 void replay_freecache(struct replay_cache *rc); 57 58 /* 59 * Check a replay cache for a message from a given address. 60 * 61 * If this is a new request, RS_NEW is returned. Caller should call 62 * replay_setreply with the results of the request. 63 * 64 * If this is a request which is currently executing 65 * (i.e. replay_setreply hasn't been called for it yet), RS_INPROGRESS 66 * is returned. The caller should silently drop the request. 67 * 68 * If a reply to this message already exists, *repmsg and *mp are set 69 * to point at the reply and, RS_DONE is returned. The caller should 70 * re-send this reply. 71 * 72 * If the attempt to update the replay cache or copy a replay failed 73 * for some reason (typically memory shortage), RS_ERROR is returned. 74 */ 75 enum replay_state replay_find(struct replay_cache *rc, 76 struct rpc_msg *msg, struct sockaddr *addr, 77 struct rpc_msg *repmsg, struct mbuf **mp); 78 79 /* 80 * Call this after executing a request to record the reply. 81 */ 82 void replay_setreply(struct replay_cache *rc, 83 struct rpc_msg *repmsg, struct sockaddr *addr, struct mbuf *m); 84 85 #endif /* !_RPC_REPLAY_H */ 86