1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
/*
*
* Copyright 2015-2016, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifndef GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_VARINT_H
#define GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_VARINT_H
#include <grpc/support/port_platform.h>
/* Helpers for hpack varint encoding */
/* length of a value that needs varint tail encoding (it's bigger than can be
bitpacked into the opcode byte) - returned value includes the length of the
opcode byte */
uint32_t grpc_chttp2_hpack_varint_length(uint32_t tail_value);
void grpc_chttp2_hpack_write_varint_tail(uint32_t tail_value, uint8_t* target,
uint32_t tail_length);
/* maximum value that can be bitpacked with the opcode if the opcode has a
prefix
of length prefix_bits */
#define GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits) \
((uint32_t)((1 << (8 - (prefix_bits))) - 1))
/* length required to bitpack a value */
#define GRPC_CHTTP2_VARINT_LENGTH(n, prefix_bits) \
((n) < GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits) \
? 1u \
: grpc_chttp2_hpack_varint_length( \
(n)-GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits)))
#define GRPC_CHTTP2_WRITE_VARINT(n, prefix_bits, prefix_or, target, length) \
do { \
uint8_t* tgt = target; \
if ((length) == 1u) { \
(tgt)[0] = (uint8_t)((prefix_or) | (n)); \
} else { \
(tgt)[0] = \
(prefix_or) | (uint8_t)GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits); \
grpc_chttp2_hpack_write_varint_tail( \
(n)-GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits), (tgt) + 1, (length)-1); \
} \
} while (0)
#endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_VARINT_H */
|
