| /* |
| * |
| * 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 <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/compression/message_compress.h" |
| |
| #include <string.h> |
| |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| |
| #include <zlib.h> |
| |
| #include "src/core/lib/slice/slice_internal.h" |
| |
| #define OUTPUT_BLOCK_SIZE 1024 |
| |
| static int zlib_body(z_stream* zs, grpc_slice_buffer* input, |
| grpc_slice_buffer* output, |
| int (*flate)(z_stream* zs, int flush)) { |
| int r; |
| int flush; |
| size_t i; |
| grpc_slice outbuf = GRPC_SLICE_MALLOC(OUTPUT_BLOCK_SIZE); |
| const uInt uint_max = ~static_cast<uInt>(0); |
| |
| GPR_ASSERT(GRPC_SLICE_LENGTH(outbuf) <= uint_max); |
| zs->avail_out = static_cast<uInt> GRPC_SLICE_LENGTH(outbuf); |
| zs->next_out = GRPC_SLICE_START_PTR(outbuf); |
| flush = Z_NO_FLUSH; |
| for (i = 0; i < input->count; i++) { |
| if (i == input->count - 1) flush = Z_FINISH; |
| GPR_ASSERT(GRPC_SLICE_LENGTH(input->slices[i]) <= uint_max); |
| zs->avail_in = static_cast<uInt> GRPC_SLICE_LENGTH(input->slices[i]); |
| zs->next_in = GRPC_SLICE_START_PTR(input->slices[i]); |
| do { |
| if (zs->avail_out == 0) { |
| grpc_slice_buffer_add_indexed(output, outbuf); |
| outbuf = GRPC_SLICE_MALLOC(OUTPUT_BLOCK_SIZE); |
| GPR_ASSERT(GRPC_SLICE_LENGTH(outbuf) <= uint_max); |
| zs->avail_out = static_cast<uInt> GRPC_SLICE_LENGTH(outbuf); |
| zs->next_out = GRPC_SLICE_START_PTR(outbuf); |
| } |
| r = flate(zs, flush); |
| if (r < 0 && r != Z_BUF_ERROR /* not fatal */) { |
| gpr_log(GPR_INFO, "zlib error (%d)", r); |
| goto error; |
| } |
| } while (zs->avail_out == 0); |
| if (zs->avail_in) { |
| gpr_log(GPR_INFO, "zlib: not all input consumed"); |
| goto error; |
| } |
| } |
| |
| GPR_ASSERT(outbuf.refcount); |
| outbuf.data.refcounted.length -= zs->avail_out; |
| grpc_slice_buffer_add_indexed(output, outbuf); |
| |
| return 1; |
| |
| error: |
| grpc_slice_unref_internal(outbuf); |
| return 0; |
| } |
| |
| static void* zalloc_gpr(void* opaque, unsigned int items, unsigned int size) { |
| return gpr_malloc(items * size); |
| } |
| |
| static void zfree_gpr(void* opaque, void* address) { gpr_free(address); } |
| |
| static int zlib_compress(grpc_slice_buffer* input, grpc_slice_buffer* output, |
| int gzip) { |
| z_stream zs; |
| int r; |
| size_t i; |
| size_t count_before = output->count; |
| size_t length_before = output->length; |
| memset(&zs, 0, sizeof(zs)); |
| zs.zalloc = zalloc_gpr; |
| zs.zfree = zfree_gpr; |
| r = deflateInit2(&zs, Z_DEFAULT_COMPRESSION, Z_DEFLATED, 15 | (gzip ? 16 : 0), |
| 8, Z_DEFAULT_STRATEGY); |
| GPR_ASSERT(r == Z_OK); |
| r = zlib_body(&zs, input, output, deflate) && output->length < input->length; |
| if (!r) { |
| for (i = count_before; i < output->count; i++) { |
| grpc_slice_unref_internal(output->slices[i]); |
| } |
| output->count = count_before; |
| output->length = length_before; |
| } |
| deflateEnd(&zs); |
| return r; |
| } |
| |
| static int zlib_decompress(grpc_slice_buffer* input, grpc_slice_buffer* output, |
| int gzip) { |
| z_stream zs; |
| int r; |
| size_t i; |
| size_t count_before = output->count; |
| size_t length_before = output->length; |
| memset(&zs, 0, sizeof(zs)); |
| zs.zalloc = zalloc_gpr; |
| zs.zfree = zfree_gpr; |
| r = inflateInit2(&zs, 15 | (gzip ? 16 : 0)); |
| GPR_ASSERT(r == Z_OK); |
| r = zlib_body(&zs, input, output, inflate); |
| if (!r) { |
| for (i = count_before; i < output->count; i++) { |
| grpc_slice_unref_internal(output->slices[i]); |
| } |
| output->count = count_before; |
| output->length = length_before; |
| } |
| inflateEnd(&zs); |
| return r; |
| } |
| |
| static int copy(grpc_slice_buffer* input, grpc_slice_buffer* output) { |
| size_t i; |
| for (i = 0; i < input->count; i++) { |
| grpc_slice_buffer_add(output, grpc_slice_ref_internal(input->slices[i])); |
| } |
| return 1; |
| } |
| |
| static int compress_inner(grpc_message_compression_algorithm algorithm, |
| grpc_slice_buffer* input, grpc_slice_buffer* output) { |
| switch (algorithm) { |
| case GRPC_MESSAGE_COMPRESS_NONE: |
| /* the fallback path always needs to be send uncompressed: we simply |
| rely on that here */ |
| return 0; |
| case GRPC_MESSAGE_COMPRESS_DEFLATE: |
| return zlib_compress(input, output, 0); |
| case GRPC_MESSAGE_COMPRESS_GZIP: |
| return zlib_compress(input, output, 1); |
| case GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT: |
| break; |
| } |
| gpr_log(GPR_ERROR, "invalid compression algorithm %d", algorithm); |
| return 0; |
| } |
| |
| int grpc_msg_compress(grpc_message_compression_algorithm algorithm, |
| grpc_slice_buffer* input, grpc_slice_buffer* output) { |
| if (!compress_inner(algorithm, input, output)) { |
| copy(input, output); |
| return 0; |
| } |
| return 1; |
| } |
| |
| int grpc_msg_decompress(grpc_message_compression_algorithm algorithm, |
| grpc_slice_buffer* input, grpc_slice_buffer* output) { |
| switch (algorithm) { |
| case GRPC_MESSAGE_COMPRESS_NONE: |
| return copy(input, output); |
| case GRPC_MESSAGE_COMPRESS_DEFLATE: |
| return zlib_decompress(input, output, 0); |
| case GRPC_MESSAGE_COMPRESS_GZIP: |
| return zlib_decompress(input, output, 1); |
| case GRPC_MESSAGE_COMPRESS_ALGORITHMS_COUNT: |
| break; |
| } |
| gpr_log(GPR_ERROR, "invalid compression algorithm %d", algorithm); |
| return 0; |
| } |