deimos.event2.tag source code

1 /*
2  * Copyright (c) 2000-2007 Niels Provos <provos@citi.umich.edu>
3  * Copyright (c) 2007-2011 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 
28 /** @file event2/tag.h
29 
30   Helper functions for reading and writing tagged data onto buffers.
31 
32  */
33 module deimos.event2.tag;
34 
35 extern (C):
36 nothrow:
37 
38 
39 /* For int types. */
40 public import deimos.event2.util;
41 import deimos.event2._d_util;
42 
43 static import deimos.event2._opaque_structs;
44 
45 alias evbuffer = deimos.event2._opaque_structs.evbuffer;
46 
47 /*
48  * Marshaling tagged data - We assume that all tags are inserted in their
49  * numeric order - so that unknown tags will always be higher than the
50  * known ones - and we can just ignore the end of an event buffer.
51  */
52 
53 void evtag_init();
54 
55 /**
56    Unmarshals the header and returns the length of the payload
57 
58    @param evbuf the buffer from which to unmarshal data
59    @param ptag a pointer in which the tag id is being stored
60    @returns -1 on failure or the number of bytes in the remaining payload.
61 */
62 int evtag_unmarshal_header(evbuffer* evbuf, ev_uint32_t* ptag);
63 
64 void evtag_marshal(evbuffer* evbuf, ev_uint32_t tag, const(void)* data,
65     ev_uint32_t len);
66 void evtag_marshal_buffer(evbuffer* evbuf, ev_uint32_t tag,
67     evbuffer* data);
68 
69 /**
70   Encode an integer and store it in an evbuffer.
71 
72   We encode integers by nybbles; the first nibble contains the number
73   of significant nibbles - 1;  this allows us to encode up to 64-bit
74   integers.  This function is byte-order independent.
75 
76   @param evbuf evbuffer to store the encoded number
77   @param number a 32-bit integer
78  */
79 void evtag_encode_int(evbuffer* evbuf, ev_uint32_t number);
80 void evtag_encode_int64(evbuffer* evbuf, ev_uint64_t number);
81 
82 void evtag_marshal_int(evbuffer* evbuf, ev_uint32_t tag,
83     ev_uint32_t integer);
84 void evtag_marshal_int64(evbuffer* evbuf, ev_uint32_t tag,
85     ev_uint64_t integer);
86 
87 void evtag_marshal_string(evbuffer* buf, ev_uint32_t tag,
88     const(char)* string);
89 
90 void evtag_marshal_timeval(evbuffer* evbuf, ev_uint32_t tag,
91     timeval* tv);
92 
93 int evtag_unmarshal(evbuffer* src, ev_uint32_t* ptag,
94     evbuffer* dst);
95 int evtag_peek(evbuffer* evbuf, ev_uint32_t* ptag);
96 int evtag_peek_length(evbuffer* evbuf, ev_uint32_t* plength);
97 int evtag_payload_length(evbuffer* evbuf, ev_uint32_t* plength);
98 int evtag_consume(evbuffer* evbuf);
99 
100 int evtag_unmarshal_int(evbuffer* evbuf, ev_uint32_t need_tag,
101     ev_uint32_t* pinteger);
102 int evtag_unmarshal_int64(evbuffer* evbuf, ev_uint32_t need_tag,
103     ev_uint64_t* pinteger);
104 
105 int evtag_unmarshal_fixed(evbuffer* src, ev_uint32_t need_tag,
106     void* data, size_t len);
107 
108 int evtag_unmarshal_string(evbuffer* evbuf, ev_uint32_t need_tag,
109     char* *pstring);
110 
111 int evtag_unmarshal_timeval(evbuffer* evbuf, ev_uint32_t need_tag,
112     timeval* ptv);