evrpc-internal.h (5711B)
1 /* 2 * Copyright (c) 2006-2007 Niels Provos <provos@citi.umich.edu> 3 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #ifndef EVRPC_INTERNAL_H_INCLUDED_ 28 #define EVRPC_INTERNAL_H_INCLUDED_ 29 30 #include "event2/http.h" 31 #include "http-internal.h" 32 33 struct evrpc; 34 struct evrpc_request_wrapper; 35 36 #define EVRPC_URI_PREFIX "/.rpc." 37 38 struct evrpc_hook { 39 TAILQ_ENTRY(evrpc_hook) next; 40 41 /* returns EVRPC_TERMINATE; if the rpc should be aborted. 42 * a hook is is allowed to rewrite the evbuffer 43 */ 44 int (*process)(void *, struct evhttp_request *, 45 struct evbuffer *, void *); 46 void *process_arg; 47 }; 48 49 TAILQ_HEAD(evrpc_hook_list, evrpc_hook); 50 51 /* 52 * this is shared between the base and the pool, so that we can reuse 53 * the hook adding functions; we alias both evrpc_pool and evrpc_base 54 * to this common structure. 55 */ 56 57 struct evrpc_hook_ctx; 58 TAILQ_HEAD(evrpc_pause_list, evrpc_hook_ctx); 59 60 struct evrpc_hooks_ { 61 /* hooks for processing outbound and inbound rpcs */ 62 struct evrpc_hook_list in_hooks; 63 struct evrpc_hook_list out_hooks; 64 65 struct evrpc_pause_list pause_requests; 66 }; 67 68 #define input_hooks common.in_hooks 69 #define output_hooks common.out_hooks 70 #define paused_requests common.pause_requests 71 72 struct evrpc_base { 73 struct evrpc_hooks_ common; 74 75 /* the HTTP server under which we register our RPC calls */ 76 struct evhttp* http_server; 77 78 /* a list of all RPCs registered with us */ 79 TAILQ_HEAD(evrpc_list, evrpc) registered_rpcs; 80 }; 81 82 struct evrpc_req_generic; 83 void evrpc_reqstate_free_(struct evrpc_req_generic* rpc_state); 84 85 /* A pool for holding evhttp_connection objects */ 86 struct evrpc_pool { 87 struct evrpc_hooks_ common; 88 89 struct event_base *base; 90 91 struct evconq connections; 92 93 int timeout; 94 95 TAILQ_HEAD(evrpc_requestq, evrpc_request_wrapper) (requests); 96 }; 97 98 struct evrpc_hook_ctx { 99 TAILQ_ENTRY(evrpc_hook_ctx) next; 100 101 void *ctx; 102 void (*cb)(void *, enum EVRPC_HOOK_RESULT); 103 }; 104 105 struct evrpc_meta { 106 TAILQ_ENTRY(evrpc_meta) next; 107 char *key; 108 109 void *data; 110 size_t data_size; 111 }; 112 113 TAILQ_HEAD(evrpc_meta_list, evrpc_meta); 114 115 struct evrpc_hook_meta { 116 struct evrpc_meta_list meta_data; 117 struct evhttp_connection *evcon; 118 }; 119 120 /* allows association of meta data with a request */ 121 static void evrpc_hook_associate_meta_(struct evrpc_hook_meta **pctx, 122 struct evhttp_connection *evcon); 123 124 /* creates a new meta data store */ 125 static struct evrpc_hook_meta *evrpc_hook_meta_new_(void); 126 127 /* frees the meta data associated with a request */ 128 static void evrpc_hook_context_free_(struct evrpc_hook_meta *ctx); 129 130 /* the server side of an rpc */ 131 132 /* We alias the RPC specific structs to this voided one */ 133 struct evrpc_req_generic { 134 /* 135 * allows association of meta data via hooks - needs to be 136 * synchronized with evrpc_request_wrapper 137 */ 138 struct evrpc_hook_meta *hook_meta; 139 140 /* the unmarshaled request object */ 141 void *request; 142 143 /* the empty reply object that needs to be filled in */ 144 void *reply; 145 146 /* 147 * the static structure for this rpc; that can be used to 148 * automatically unmarshal and marshal the http buffers. 149 */ 150 struct evrpc *rpc; 151 152 /* 153 * the http request structure on which we need to answer. 154 */ 155 struct evhttp_request* http_req; 156 157 /* 158 * Temporary data store for marshaled data 159 */ 160 struct evbuffer* rpc_data; 161 }; 162 163 /* the client side of an rpc request */ 164 struct evrpc_request_wrapper { 165 /* 166 * allows association of meta data via hooks - needs to be 167 * synchronized with evrpc_req_generic. 168 */ 169 struct evrpc_hook_meta *hook_meta; 170 171 TAILQ_ENTRY(evrpc_request_wrapper) next; 172 173 /* pool on which this rpc request is being made */ 174 struct evrpc_pool *pool; 175 176 /* connection on which the request is being sent */ 177 struct evhttp_connection *evcon; 178 179 /* the actual request */ 180 struct evhttp_request *req; 181 182 /* event for implementing request timeouts */ 183 struct event ev_timeout; 184 185 /* the name of the rpc */ 186 char *name; 187 188 /* callback */ 189 void (*cb)(struct evrpc_status*, void *request, void *reply, void *arg); 190 void *cb_arg; 191 192 void *request; 193 void *reply; 194 195 /* unmarshals the buffer into the proper request structure */ 196 void (*request_marshal)(struct evbuffer *, void *); 197 198 /* removes all stored state in the reply */ 199 void (*reply_clear)(void *); 200 201 /* marshals the reply into a buffer */ 202 int (*reply_unmarshal)(void *, struct evbuffer*); 203 }; 204 205 #endif /* EVRPC_INTERNAL_H_INCLUDED_ */