1/*
2 *
3 * Copyright 2016 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19#ifndef GRPC_IMPL_CODEGEN_COMPRESSION_TYPES_H
20#define GRPC_IMPL_CODEGEN_COMPRESSION_TYPES_H
21
22#include <grpc/impl/codegen/port_platform.h>
23
24#ifdef __cplusplus
25extern "C" {
26#endif
27
28/** To be used as initial metadata key for the request of a concrete compression
29 * algorithm */
30#define GRPC_COMPRESSION_REQUEST_ALGORITHM_MD_KEY \
31 "grpc-internal-encoding-request"
32
33/** To be used in channel arguments.
34 *
35 * \addtogroup grpc_arg_keys
36 * \{ */
37/** Default compression algorithm for the channel.
38 * Its value is an int from the \a grpc_compression_algorithm enum. */
39#define GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM \
40 "grpc.default_compression_algorithm"
41/** Default compression level for the channel.
42 * Its value is an int from the \a grpc_compression_level enum. */
43#define GRPC_COMPRESSION_CHANNEL_DEFAULT_LEVEL "grpc.default_compression_level"
44/** Compression algorithms supported by the channel.
45 * Its value is a bitset (an int). Bits correspond to algorithms in \a
46 * grpc_compression_algorithm. For example, its LSB corresponds to
47 * GRPC_COMPRESS_NONE, the next bit to GRPC_COMPRESS_DEFLATE, etc.
48 * Unset bits disable support for the algorithm. By default all algorithms are
49 * supported. It's not possible to disable GRPC_COMPRESS_NONE (the attempt will
50 * be ignored). */
51#define GRPC_COMPRESSION_CHANNEL_ENABLED_ALGORITHMS_BITSET \
52 "grpc.compression_enabled_algorithms_bitset"
53/** \} */
54
55/** The various compression algorithms supported by gRPC (not sorted by
56 * compression level) */
57typedef enum {
58 GRPC_COMPRESS_NONE = 0,
59 GRPC_COMPRESS_DEFLATE,
60 GRPC_COMPRESS_GZIP,
61 /* EXPERIMENTAL: Stream compression is currently experimental. */
62 GRPC_COMPRESS_STREAM_GZIP,
63 /* TODO(ctiller): snappy */
64 GRPC_COMPRESS_ALGORITHMS_COUNT
65} grpc_compression_algorithm;
66
67/** Compression levels allow a party with knowledge of its peer's accepted
68 * encodings to request compression in an abstract way. The level-algorithm
69 * mapping is performed internally and depends on the peer's supported
70 * compression algorithms. */
71typedef enum {
72 GRPC_COMPRESS_LEVEL_NONE = 0,
73 GRPC_COMPRESS_LEVEL_LOW,
74 GRPC_COMPRESS_LEVEL_MED,
75 GRPC_COMPRESS_LEVEL_HIGH,
76 GRPC_COMPRESS_LEVEL_COUNT
77} grpc_compression_level;
78
79typedef struct grpc_compression_options {
80 /** All algs are enabled by default. This option corresponds to the channel
81 * argument key behind \a GRPC_COMPRESSION_CHANNEL_ENABLED_ALGORITHMS_BITSET
82 */
83 uint32_t enabled_algorithms_bitset;
84
85 /** The default compression level. It'll be used in the absence of call
86 * specific settings. This option corresponds to the channel
87 * argument key behind \a GRPC_COMPRESSION_CHANNEL_DEFAULT_LEVEL. If present,
88 * takes precedence over \a default_algorithm.
89 * TODO(dgq): currently only available for server channels. */
90 struct grpc_compression_options_default_level {
91 int is_set;
92 grpc_compression_level level;
93 } default_level;
94
95 /** The default message compression algorithm. It'll be used in the absence of
96 * call specific settings. This option corresponds to the channel argument key
97 * behind \a GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM. */
98 struct grpc_compression_options_default_algorithm {
99 int is_set;
100 grpc_compression_algorithm algorithm;
101 } default_algorithm;
102} grpc_compression_options;
103
104#ifdef __cplusplus
105}
106#endif
107
108#endif /* GRPC_IMPL_CODEGEN_COMPRESSION_TYPES_H */
109

source code of include/grpc/impl/codegen/compression_types.h