xref: /freebsd/contrib/libevent/include/event2/rpc_struct.h (revision b50261e21f39a6c7249a49e7b60aa878c98512a8)
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 EVENT2_RPC_STRUCT_H_INCLUDED_
28 #define EVENT2_RPC_STRUCT_H_INCLUDED_
29 
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33 
34 /** @file event2/rpc_struct.h
35 
36   Structures used by rpc.h.  Using these structures directly may harm
37   forward compatibility: be careful!
38 
39  */
40 
41 /* Fix so that people don't have to run with <sys/queue.h> */
42 #ifndef TAILQ_ENTRY
43 #define EVENT_DEFINED_TQENTRY_
44 #define TAILQ_ENTRY(type)						\
45 struct {								\
46 	struct type *tqe_next;	/* next element */			\
47 	struct type **tqe_prev;	/* address of previous next element */	\
48 }
49 #endif /* !TAILQ_ENTRY */
50 
51 /**
52  * provides information about the completed RPC request.
53  */
54 struct evrpc_status {
55 #define EVRPC_STATUS_ERR_NONE		0
56 #define EVRPC_STATUS_ERR_TIMEOUT	1
57 #define EVRPC_STATUS_ERR_BADPAYLOAD	2
58 #define EVRPC_STATUS_ERR_UNSTARTED	3
59 #define EVRPC_STATUS_ERR_HOOKABORTED	4
60 	int error;
61 
62 	/* for looking at headers or other information */
63 	struct evhttp_request *http_req;
64 };
65 
66 /* the structure below needs to be synchronized with evrpc_req_generic */
67 
68 /* Encapsulates a request */
69 struct evrpc {
70 	TAILQ_ENTRY(evrpc) next;
71 
72 	/* the URI at which the request handler lives */
73 	const char* uri;
74 
75 	/* creates a new request structure */
76 	void *(*request_new)(void *);
77 	void *request_new_arg;
78 
79 	/* frees the request structure */
80 	void (*request_free)(void *);
81 
82 	/* unmarshals the buffer into the proper request structure */
83 	int (*request_unmarshal)(void *, struct evbuffer *);
84 
85 	/* creates a new reply structure */
86 	void *(*reply_new)(void *);
87 	void *reply_new_arg;
88 
89 	/* frees the reply structure */
90 	void (*reply_free)(void *);
91 
92 	/* verifies that the reply is valid */
93 	int (*reply_complete)(void *);
94 
95 	/* marshals the reply into a buffer */
96 	void (*reply_marshal)(struct evbuffer*, void *);
97 
98 	/* the callback invoked for each received rpc */
99 	void (*cb)(struct evrpc_req_generic *, void *);
100 	void *cb_arg;
101 
102 	/* reference for further configuration */
103 	struct evrpc_base *base;
104 };
105 
106 #ifdef EVENT_DEFINED_TQENTRY_
107 #undef TAILQ_ENTRY
108 #endif
109 
110 #ifdef __cplusplus
111 }
112 #endif
113 
114 #endif /* EVENT2_RPC_STRUCT_H_INCLUDED_ */
115