1 /* $NetBSD: evrpc-internal.h,v 1.6 2020/05/25 20:47:33 christos Exp $ */ 2 3 /* 4 * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> 5 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 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. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 #ifndef EVRPC_INTERNAL_H_INCLUDED_ 30 #define EVRPC_INTERNAL_H_INCLUDED_ 31 32 #include "event2/http.h" 33 #include "http-internal.h" 34 35 struct evrpc; 36 struct evrpc_request_wrapper; 37 38 #define EVRPC_URI_PREFIX "/.rpc." 39 40 struct evrpc_hook { 41 TAILQ_ENTRY(evrpc_hook) next; 42 43 /* returns EVRPC_TERMINATE; if the rpc should be aborted. 44 * a hook is is allowed to rewrite the evbuffer 45 */ 46 int (*process)(void *, struct evhttp_request *, 47 struct evbuffer *, void *); 48 void *process_arg; 49 }; 50 51 TAILQ_HEAD(evrpc_hook_list, evrpc_hook); 52 53 /* 54 * this is shared between the base and the pool, so that we can reuse 55 * the hook adding functions; we alias both evrpc_pool and evrpc_base 56 * to this common structure. 57 */ 58 59 struct evrpc_hook_ctx; 60 TAILQ_HEAD(evrpc_pause_list, evrpc_hook_ctx); 61 62 struct evrpc_hooks_ { 63 /* hooks for processing outbound and inbound rpcs */ 64 struct evrpc_hook_list in_hooks; 65 struct evrpc_hook_list out_hooks; 66 67 struct evrpc_pause_list pause_requests; 68 }; 69 70 #define input_hooks common.in_hooks 71 #define output_hooks common.out_hooks 72 #define paused_requests common.pause_requests 73 74 struct evrpc_base { 75 struct evrpc_hooks_ common; 76 77 /* the HTTP server under which we register our RPC calls */ 78 struct evhttp* http_server; 79 80 /* a list of all RPCs registered with us */ 81 TAILQ_HEAD(evrpc_list, evrpc) registered_rpcs; 82 }; 83 84 struct evrpc_req_generic; 85 void evrpc_reqstate_free_(struct evrpc_req_generic* rpc_state); 86 87 /* A pool for holding evhttp_connection objects */ 88 struct evrpc_pool { 89 struct evrpc_hooks_ common; 90 91 struct event_base *base; 92 93 struct evconq connections; 94 95 int timeout; 96 97 TAILQ_HEAD(evrpc_requestq, evrpc_request_wrapper) (requests); 98 }; 99 100 struct evrpc_hook_ctx { 101 TAILQ_ENTRY(evrpc_hook_ctx) next; 102 103 void *ctx; 104 void (*cb)(void *, enum EVRPC_HOOK_RESULT); 105 }; 106 107 struct evrpc_meta { 108 TAILQ_ENTRY(evrpc_meta) next; 109 char *key; 110 111 void *data; 112 size_t data_size; 113 }; 114 115 TAILQ_HEAD(evrpc_meta_list, evrpc_meta); 116 117 struct evrpc_hook_meta { 118 struct evrpc_meta_list meta_data; 119 struct evhttp_connection *evcon; 120 }; 121 122 /* allows association of meta data with a request */ 123 static void evrpc_hook_associate_meta_(struct evrpc_hook_meta **pctx, 124 struct evhttp_connection *evcon); 125 126 /* creates a new meta data store */ 127 static struct evrpc_hook_meta *evrpc_hook_meta_new_(void); 128 129 /* frees the meta data associated with a request */ 130 static void evrpc_hook_context_free_(struct evrpc_hook_meta *ctx); 131 132 /* the server side of an rpc */ 133 134 /* We alias the RPC specific structs to this voided one */ 135 struct evrpc_req_generic { 136 /* 137 * allows association of meta data via hooks - needs to be 138 * synchronized with evrpc_request_wrapper 139 */ 140 struct evrpc_hook_meta *hook_meta; 141 142 /* the unmarshaled request object */ 143 void *request; 144 145 /* the empty reply object that needs to be filled in */ 146 void *reply; 147 148 /* 149 * the static structure for this rpc; that can be used to 150 * automatically unmarshal and marshal the http buffers. 151 */ 152 struct evrpc *rpc; 153 154 /* 155 * the http request structure on which we need to answer. 156 */ 157 struct evhttp_request* http_req; 158 159 /* 160 * Temporary data store for marshaled data 161 */ 162 struct evbuffer* rpc_data; 163 }; 164 165 /* the client side of an rpc request */ 166 struct evrpc_request_wrapper { 167 /* 168 * allows association of meta data via hooks - needs to be 169 * synchronized with evrpc_req_generic. 170 */ 171 struct evrpc_hook_meta *hook_meta; 172 173 TAILQ_ENTRY(evrpc_request_wrapper) next; 174 175 /* pool on which this rpc request is being made */ 176 struct evrpc_pool *pool; 177 178 /* connection on which the request is being sent */ 179 struct evhttp_connection *evcon; 180 181 /* the actual request */ 182 struct evhttp_request *req; 183 184 /* event for implementing request timeouts */ 185 struct event ev_timeout; 186 187 /* the name of the rpc */ 188 char *name; 189 190 /* callback */ 191 void (*cb)(struct evrpc_status*, void *request, void *reply, void *arg); 192 void *cb_arg; 193 194 void *request; 195 void *reply; 196 197 /* unmarshals the buffer into the proper request structure */ 198 void (*request_marshal)(struct evbuffer *, void *); 199 200 /* removes all stored state in the reply */ 201 void (*reply_clear)(void *); 202 203 /* marshals the reply into a buffer */ 204 int (*reply_unmarshal)(void *, struct evbuffer*); 205 }; 206 207 #endif /* EVRPC_INTERNAL_H_INCLUDED_ */ 208