xref: /freebsd/contrib/ntp/sntp/libevent/include/event2/bufferevent_struct.h (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
1 /*
2  * Copyright (c) 2000-2007 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_BUFFEREVENT_STRUCT_H_INCLUDED_
28 #define EVENT2_BUFFEREVENT_STRUCT_H_INCLUDED_
29 
30 /** @file event2/bufferevent_struct.h
31 
32   Data structures for bufferevents.  Using these structures may hurt forward
33   compatibility with later versions of Libevent: be careful!
34 
35   @deprecated Use of bufferevent_struct.h is completely deprecated; these
36     structures are only exposed for backward compatibility with programs
37     written before Libevent 2.0 that used them.
38  */
39 
40 #ifdef __cplusplus
41 extern "C" {
42 #endif
43 
44 #include <event2/event-config.h>
45 #ifdef EVENT__HAVE_SYS_TYPES_H
46 #include <sys/types.h>
47 #endif
48 #ifdef EVENT__HAVE_SYS_TIME_H
49 #include <sys/time.h>
50 #endif
51 
52 /* For int types. */
53 #include <event2/util.h>
54 /* For struct event */
55 #include <event2/event_struct.h>
56 
57 struct event_watermark {
58 	size_t low;
59 	size_t high;
60 };
61 
62 /**
63   Shared implementation of a bufferevent.
64 
65   This type is exposed only because it was exposed in previous versions,
66   and some people's code may rely on manipulating it.  Otherwise, you
67   should really not rely on the layout, size, or contents of this structure:
68   it is fairly volatile, and WILL change in future versions of the code.
69 **/
70 struct bufferevent {
71 	/** Event base for which this bufferevent was created. */
72 	struct event_base *ev_base;
73 	/** Pointer to a table of function pointers to set up how this
74 	    bufferevent behaves. */
75 	const struct bufferevent_ops *be_ops;
76 
77 	/** A read event that triggers when a timeout has happened or a socket
78 	    is ready to read data.  Only used by some subtypes of
79 	    bufferevent. */
80 	struct event ev_read;
81 	/** A write event that triggers when a timeout has happened or a socket
82 	    is ready to write data.  Only used by some subtypes of
83 	    bufferevent. */
84 	struct event ev_write;
85 
86 	/** An input buffer. Only the bufferevent is allowed to add data to
87 	    this buffer, though the user is allowed to drain it. */
88 	struct evbuffer *input;
89 
90 	/** An input buffer. Only the bufferevent is allowed to drain data
91 	    from this buffer, though the user is allowed to add it. */
92 	struct evbuffer *output;
93 
94 	struct event_watermark wm_read;
95 	struct event_watermark wm_write;
96 
97 	bufferevent_data_cb readcb;
98 	bufferevent_data_cb writecb;
99 	/* This should be called 'eventcb', but renaming it would break
100 	 * backward compatibility */
101 	bufferevent_event_cb errorcb;
102 	void *cbarg;
103 
104 	struct timeval timeout_read;
105 	struct timeval timeout_write;
106 
107 	/** Events that are currently enabled: currently EV_READ and EV_WRITE
108 	    are supported. */
109 	short enabled;
110 };
111 
112 #ifdef __cplusplus
113 }
114 #endif
115 
116 #endif /* EVENT2_BUFFEREVENT_STRUCT_H_INCLUDED_ */
117