2 * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu>
3 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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.
27 #ifndef _EVENT2_TAG_H_
28 #define _EVENT2_TAG_H_
30 /** @file event2/tag.h
32 Helper functions for reading and writing tagged data onto buffers.
40 #include <event2/event-config.h>
41 #ifdef _EVENT_HAVE_SYS_TYPES_H
42 #include <sys/types.h>
44 #ifdef _EVENT_HAVE_SYS_TIME_H
49 #include <event2/util.h>
54 * Marshaling tagged data - We assume that all tags are inserted in their
55 * numeric order - so that unknown tags will always be higher than the
56 * known ones - and we can just ignore the end of an event buffer.
59 void evtag_init(void);
62 Unmarshals the header and returns the length of the payload
64 @param evbuf the buffer from which to unmarshal data
65 @param ptag a pointer in which the tag id is being stored
66 @returns -1 on failure or the number of bytes in the remaining payload.
68 int evtag_unmarshal_header(struct evbuffer
*evbuf
, ev_uint32_t
*ptag
);
70 void evtag_marshal(struct evbuffer
*evbuf
, ev_uint32_t tag
, const void *data
,
72 void evtag_marshal_buffer(struct evbuffer
*evbuf
, ev_uint32_t tag
,
73 struct evbuffer
*data
);
76 Encode an integer and store it in an evbuffer.
78 We encode integers by nybbles; the first nibble contains the number
79 of significant nibbles - 1; this allows us to encode up to 64-bit
80 integers. This function is byte-order independent.
82 @param evbuf evbuffer to store the encoded number
83 @param number a 32-bit integer
85 void evtag_encode_int(struct evbuffer
*evbuf
, ev_uint32_t number
);
86 void evtag_encode_int64(struct evbuffer
*evbuf
, ev_uint64_t number
);
88 void evtag_marshal_int(struct evbuffer
*evbuf
, ev_uint32_t tag
,
90 void evtag_marshal_int64(struct evbuffer
*evbuf
, ev_uint32_t tag
,
93 void evtag_marshal_string(struct evbuffer
*buf
, ev_uint32_t tag
,
96 void evtag_marshal_timeval(struct evbuffer
*evbuf
, ev_uint32_t tag
,
99 int evtag_unmarshal(struct evbuffer
*src
, ev_uint32_t
*ptag
,
100 struct evbuffer
*dst
);
101 int evtag_peek(struct evbuffer
*evbuf
, ev_uint32_t
*ptag
);
102 int evtag_peek_length(struct evbuffer
*evbuf
, ev_uint32_t
*plength
);
103 int evtag_payload_length(struct evbuffer
*evbuf
, ev_uint32_t
*plength
);
104 int evtag_consume(struct evbuffer
*evbuf
);
106 int evtag_unmarshal_int(struct evbuffer
*evbuf
, ev_uint32_t need_tag
,
107 ev_uint32_t
*pinteger
);
108 int evtag_unmarshal_int64(struct evbuffer
*evbuf
, ev_uint32_t need_tag
,
109 ev_uint64_t
*pinteger
);
111 int evtag_unmarshal_fixed(struct evbuffer
*src
, ev_uint32_t need_tag
,
112 void *data
, size_t len
);
114 int evtag_unmarshal_string(struct evbuffer
*evbuf
, ev_uint32_t need_tag
,
117 int evtag_unmarshal_timeval(struct evbuffer
*evbuf
, ev_uint32_t need_tag
,
118 struct timeval
*ptv
);
124 #endif /* _EVENT2_TAG_H_ */