src/core/lib/compression/stream_compression.cc

   1 /*
   2  *
   3  * Copyright 2017 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 #include <grpc/support/port_platform.h>
  20
  21 #include <grpc/support/log.h>
  22
  23 #include "src/core/lib/compression/stream_compression.h"
  24 #include "src/core/lib/compression/stream_compression_gzip.h"
  25 #include "src/core/lib/slice/slice_utils.h"
  26
  27 extern const grpc_stream_compression_vtable
  28     grpc_stream_compression_identity_vtable;
  29
  30 bool grpc_stream_compress(grpc_stream_compression_context* ctx,
  31                           grpc_slice_buffer* in, grpc_slice_buffer* out,
  32                           size_t* output_size, size_t max_output_size,
  33                           grpc_stream_compression_flush flush) {
  34   return ctx->vtable->compress(ctx, in, out, output_size, max_output_size,
  35                                flush);
  36 }
  37
  38 bool grpc_stream_decompress(grpc_stream_compression_context* ctx,
  39                             grpc_slice_buffer* in, grpc_slice_buffer* out,
  40                             size_t* output_size, size_t max_output_size,
  41                             bool* end_of_context) {
  42   return ctx->vtable->decompress(ctx, in, out, output_size, max_output_size,
  43                                  end_of_context);
  44 }
  45
  46 grpc_stream_compression_context* grpc_stream_compression_context_create(
  47     grpc_stream_compression_method method) {
  48   switch (method) {
  49     case GRPC_STREAM_COMPRESSION_IDENTITY_COMPRESS:
  50     case GRPC_STREAM_COMPRESSION_IDENTITY_DECOMPRESS:
  51       return grpc_stream_compression_identity_vtable.context_create(method);
  52     case GRPC_STREAM_COMPRESSION_GZIP_COMPRESS:
  53     case GRPC_STREAM_COMPRESSION_GZIP_DECOMPRESS:
  54       return grpc_stream_compression_gzip_vtable.context_create(method);
  55     default:
  56       gpr_log(GPR_ERROR, "Unknown stream compression method: %d", method);
  57       return nullptr;
  58   }
  59 }
  60
  61 void grpc_stream_compression_context_destroy(
  62     grpc_stream_compression_context* ctx) {
  63   ctx->vtable->context_destroy(ctx);
  64 }
  65
  66 int grpc_stream_compression_method_parse(
  67     grpc_slice value, bool is_compress,
  68     grpc_stream_compression_method* method) {
  69   if (grpc_slice_eq_static_interned(value, GRPC_MDSTR_IDENTITY)) {
  70     *method = is_compress ? GRPC_STREAM_COMPRESSION_IDENTITY_COMPRESS
  71                           : GRPC_STREAM_COMPRESSION_IDENTITY_DECOMPRESS;
  72     return 1;
  73   } else if (grpc_slice_eq_static_interned(value, GRPC_MDSTR_GZIP)) {
  74     *method = is_compress ? GRPC_STREAM_COMPRESSION_GZIP_COMPRESS
  75                           : GRPC_STREAM_COMPRESSION_GZIP_DECOMPRESS;
  76     return 1;
  77   } else {
  78     return 0;
  79   }
  80 }