diff options
Diffstat (limited to 'src/core/lib/compression/compression_internal.cc')
| -rw-r--r-- | src/core/lib/compression/compression_internal.cc | 313 |
1 files changed, 313 insertions, 0 deletions
diff --git a/src/core/lib/compression/compression_internal.cc b/src/core/lib/compression/compression_internal.cc new file mode 100644 index 0000000000..e31eb830f1 --- /dev/null +++ b/src/core/lib/compression/compression_internal.cc @@ -0,0 +1,313 @@ +/* + * + * Copyright 2015 gRPC authors. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + */ + +#include <stdlib.h> +#include <string.h> + +#include <grpc/compression.h> +#include <grpc/support/useful.h> + +#include "src/core/lib/compression/algorithm_metadata.h" +#include "src/core/lib/compression/compression_internal.h" +#include "src/core/lib/surface/api_trace.h" +#include "src/core/lib/transport/static_metadata.h" + +/* Interfaces related to MD */ + +grpc_message_compression_algorithm +grpc_message_compression_algorithm_from_slice(grpc_slice str) { + if (grpc_slice_eq(str, GRPC_MDSTR_IDENTITY)) + return GRPC_MESSAGE_COMPRESS_NONE; + if (grpc_slice_eq(str, GRPC_MDSTR_DEFLATE)) + return GRPC_MESSAGE_COMPRESS_DEFLATE; + if (grpc_slice_eq(str, GRPC_MDSTR_GZIP)) return GRPC_MESSAGE_COMPRESS_GZIP; + return GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT; +} + +grpc_stream_compression_algorithm grpc_stream_compression_algorithm_from_slice( + grpc_slice str) { + if (grpc_slice_eq(str, GRPC_MDSTR_IDENTITY)) return GRPC_STREAM_COMPRESS_NONE; + if (grpc_slice_eq(str, GRPC_MDSTR_GZIP)) return GRPC_STREAM_COMPRESS_GZIP; + return GRPC_STREAM_COMPRESS_ALGORITHMS_COUNT; +} + +grpc_mdelem grpc_message_compression_encoding_mdelem( + grpc_message_compression_algorithm algorithm) { + switch (algorithm) { + case GRPC_MESSAGE_COMPRESS_NONE: + return GRPC_MDELEM_GRPC_ENCODING_IDENTITY; + case GRPC_MESSAGE_COMPRESS_DEFLATE: + return GRPC_MDELEM_GRPC_ENCODING_DEFLATE; + case GRPC_MESSAGE_COMPRESS_GZIP: + return GRPC_MDELEM_GRPC_ENCODING_GZIP; + default: + break; + } + return GRPC_MDNULL; +} + +grpc_mdelem grpc_stream_compression_encoding_mdelem( + grpc_stream_compression_algorithm algorithm) { + switch (algorithm) { + case GRPC_STREAM_COMPRESS_NONE: + return GRPC_MDELEM_CONTENT_ENCODING_IDENTITY; + case GRPC_STREAM_COMPRESS_GZIP: + return GRPC_MDELEM_CONTENT_ENCODING_GZIP; + default: + break; + } + return GRPC_MDNULL; +} + +/* Interfaces performing transformation between compression algorithms and + * levels. */ +grpc_message_compression_level +grpc_compression_level_to_message_compression_level( + grpc_compression_level level) { + if (level >= GRPC_COMPRESS_LEVEL_COUNT) { + return GRPC_MESSAGE_COMPRESS_LEVEL_NONE; + } + return (grpc_message_compression_level)( + (uint32_t)(level - GRPC_COMPRESS_LEVEL_NONE) + + (uint32_t)GRPC_MESSAGE_COMPRESS_LEVEL_NONE); +} + +grpc_stream_compression_level +grpc_compression_level_to_stream_compression_level( + grpc_compression_level level) { + if (level >= GRPC_COMPRESS_LEVEL_COUNT) { + return GRPC_STREAM_COMPRESS_LEVEL_NONE; + } + return (grpc_stream_compression_level)( + (uint32_t)(level - (GRPC_MESSAGE_COMPRESS_LEVEL_COUNT - 1) - + GRPC_COMPRESS_LEVEL_NONE) + + (uint32_t)GRPC_STREAM_COMPRESS_LEVEL_NONE); +} + +grpc_message_compression_algorithm +grpc_compression_algorithm_to_message_compression_algorithm( + grpc_compression_algorithm algo) { + switch (algo) { + case GRPC_COMPRESS_MESSAGE_DEFLATE: + return GRPC_MESSAGE_COMPRESS_DEFLATE; + case GRPC_COMPRESS_MESSAGE_GZIP: + return GRPC_MESSAGE_COMPRESS_GZIP; + default: + return GRPC_MESSAGE_COMPRESS_NONE; + } +} + +grpc_stream_compression_algorithm +grpc_compression_algorithm_to_stream_compression_algorithm( + grpc_compression_algorithm algo) { + switch (algo) { + case GRPC_COMPRESS_STREAM_GZIP: + return GRPC_STREAM_COMPRESS_GZIP; + default: + return GRPC_STREAM_COMPRESS_NONE; + } +} + +uint32_t grpc_compression_bitset_to_message_bitset(uint32_t bitset) { + return bitset & ((1u << GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT) - 1); +} + +uint32_t grpc_compression_bitset_to_stream_bitset(uint32_t bitset) { + uint32_t identity = (bitset & 1u); + uint32_t other_bits = + (bitset >> (GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT - 1)) & + ((1u << GRPC_STREAM_COMPRESS_ALGORITHMS_COUNT) - 2); + return identity | other_bits; +} + +uint32_t grpc_compression_bitset_from_message_stream_compression_bitset( + uint32_t message_bitset, uint32_t stream_bitset) { + uint32_t offset_stream_bitset = + (stream_bitset & 1u) | + ((stream_bitset & (~1u)) << (GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT - 1)); + return message_bitset | offset_stream_bitset; +} + +int grpc_compression_algorithm_from_message_stream_compression_algorithm( + grpc_compression_algorithm *algorithm, + grpc_message_compression_algorithm message_algorithm, + grpc_stream_compression_algorithm stream_algorithm) { + if (message_algorithm != GRPC_MESSAGE_COMPRESS_NONE && + stream_algorithm != GRPC_STREAM_COMPRESS_NONE) { + *algorithm = GRPC_COMPRESS_NONE; + return 0; + } + if (message_algorithm == GRPC_MESSAGE_COMPRESS_NONE) { + switch (stream_algorithm) { + case GRPC_STREAM_COMPRESS_NONE: + *algorithm = GRPC_COMPRESS_NONE; + return 1; + case GRPC_STREAM_COMPRESS_GZIP: + *algorithm = GRPC_COMPRESS_STREAM_GZIP; + return 1; + default: + *algorithm = GRPC_COMPRESS_NONE; + return 0; + } + } else { + switch (message_algorithm) { + case GRPC_MESSAGE_COMPRESS_NONE: + *algorithm = GRPC_COMPRESS_NONE; + return 1; + case GRPC_MESSAGE_COMPRESS_DEFLATE: + *algorithm = GRPC_COMPRESS_MESSAGE_DEFLATE; + return 1; + case GRPC_MESSAGE_COMPRESS_GZIP: + *algorithm = GRPC_COMPRESS_MESSAGE_GZIP; + return 1; + default: + *algorithm = GRPC_COMPRESS_NONE; + return 0; + } + } + return 0; +} + +/* Interfaces for message compression. */ + +int grpc_message_compression_algorithm_name( + grpc_message_compression_algorithm algorithm, const char **name) { + GRPC_API_TRACE( + "grpc_message_compression_algorithm_parse(algorithm=%d, name=%p)", 2, + ((int)algorithm, name)); + switch (algorithm) { + case GRPC_MESSAGE_COMPRESS_NONE: + *name = "identity"; + return 1; + case GRPC_MESSAGE_COMPRESS_DEFLATE: + *name = "deflate"; + return 1; + case GRPC_MESSAGE_COMPRESS_GZIP: + *name = "gzip"; + return 1; + case GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT: + return 0; + } + return 0; +} + +/* TODO(dgq): Add the ability to specify parameters to the individual + * compression algorithms */ +grpc_message_compression_algorithm grpc_message_compression_algorithm_for_level( + grpc_message_compression_level level, uint32_t accepted_encodings) { + GRPC_API_TRACE("grpc_message_compression_algorithm_for_level(level=%d)", 1, + ((int)level)); + if (level > GRPC_MESSAGE_COMPRESS_LEVEL_HIGH) { + gpr_log(GPR_ERROR, "Unknown message compression level %d.", (int)level); + abort(); + } + + const size_t num_supported = + GPR_BITCOUNT(accepted_encodings) - 1; /* discard NONE */ + if (level == GRPC_MESSAGE_COMPRESS_LEVEL_NONE || num_supported == 0) { + return GRPC_MESSAGE_COMPRESS_NONE; + } + + GPR_ASSERT(level > 0); + + /* Establish a "ranking" or compression algorithms in increasing order of + * compression. + * This is simplistic and we will probably want to introduce other dimensions + * in the future (cpu/memory cost, etc). */ + const grpc_message_compression_algorithm algos_ranking[] = { + GRPC_MESSAGE_COMPRESS_GZIP, GRPC_MESSAGE_COMPRESS_DEFLATE}; + + /* intersect algos_ranking with the supported ones keeping the ranked order */ + grpc_message_compression_algorithm + sorted_supported_algos[GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT]; + size_t algos_supported_idx = 0; + for (size_t i = 0; i < GPR_ARRAY_SIZE(algos_ranking); i++) { + const grpc_message_compression_algorithm alg = algos_ranking[i]; + for (size_t j = 0; j < num_supported; j++) { + if (GPR_BITGET(accepted_encodings, alg) == 1) { + /* if \a alg in supported */ + sorted_supported_algos[algos_supported_idx++] = alg; + break; + } + } + if (algos_supported_idx == num_supported) break; + } + + switch (level) { + case GRPC_MESSAGE_COMPRESS_LEVEL_NONE: + abort(); /* should have been handled already */ + case GRPC_MESSAGE_COMPRESS_LEVEL_LOW: + return sorted_supported_algos[0]; + case GRPC_MESSAGE_COMPRESS_LEVEL_MED: + return sorted_supported_algos[num_supported / 2]; + case GRPC_MESSAGE_COMPRESS_LEVEL_HIGH: + return sorted_supported_algos[num_supported - 1]; + default: + abort(); + }; +} + +int grpc_message_compression_algorithm_parse( + grpc_slice value, grpc_message_compression_algorithm *algorithm) { + if (grpc_slice_eq(value, GRPC_MDSTR_IDENTITY)) { + *algorithm = GRPC_MESSAGE_COMPRESS_NONE; + return 1; + } else if (grpc_slice_eq(value, GRPC_MDSTR_DEFLATE)) { + *algorithm = GRPC_MESSAGE_COMPRESS_DEFLATE; + return 1; + } else if (grpc_slice_eq(value, GRPC_MDSTR_GZIP)) { + *algorithm = GRPC_MESSAGE_COMPRESS_GZIP; + return 1; + } else { + return 0; + } + return 0; +} + +/* Interfaces for stream compression. */ + +grpc_stream_compression_algorithm grpc_stream_compression_algorithm_for_level( + grpc_stream_compression_level level, uint32_t accepted_encodings) { + GRPC_API_TRACE("grpc_stream_compression_algorithm_for_level(level=%d)", 1, + ((int)level)); + if (level > GRPC_STREAM_COMPRESS_LEVEL_HIGH) { + gpr_log(GPR_ERROR, "Unknown stream compression level %d.", (int)level); + abort(); + } + + /* TODO(mxyan): Use more sophisticated scheme when more algorithms added. */ + if (level != GRPC_STREAM_COMPRESS_LEVEL_NONE && + GPR_BITGET(accepted_encodings, GRPC_STREAM_COMPRESS_GZIP)) { + return GRPC_STREAM_COMPRESS_GZIP; + } + return GRPC_STREAM_COMPRESS_NONE; +} + +int grpc_stream_compression_algorithm_parse( + grpc_slice value, grpc_stream_compression_algorithm *algorithm) { + if (grpc_slice_eq(value, GRPC_MDSTR_IDENTITY)) { + *algorithm = GRPC_STREAM_COMPRESS_NONE; + return 1; + } else if (grpc_slice_eq(value, GRPC_MDSTR_GZIP)) { + *algorithm = GRPC_STREAM_COMPRESS_GZIP; + return 1; + } else { + return 0; + } + return 0; +} |