| /* |
| * |
| * Copyright 2015, 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_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_ENCODER_H |
| #define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_ENCODER_H |
| |
| #include "src/core/transport/chttp2/frame.h" |
| #include "src/core/transport/metadata.h" |
| #include "src/core/transport/metadata_batch.h" |
| #include <grpc/support/port_platform.h> |
| #include <grpc/support/slice.h> |
| #include <grpc/support/slice_buffer.h> |
| |
| #define GRPC_CHTTP2_HPACKC_NUM_FILTERS 256 |
| #define GRPC_CHTTP2_HPACKC_NUM_VALUES 256 |
| /* initial table size, per spec */ |
| #define GRPC_CHTTP2_HPACKC_INITIAL_TABLE_SIZE 4096 |
| /* maximum table size we'll actually use */ |
| #define GRPC_CHTTP2_HPACKC_MAX_TABLE_SIZE (1024 * 1024) |
| |
| typedef struct { |
| uint32_t filter_elems_sum; |
| uint32_t max_table_size; |
| uint32_t max_table_elems; |
| uint32_t cap_table_elems; |
| /** if non-zero, advertise to the decoder that we'll start using a table |
| of this size */ |
| uint8_t advertise_table_size_change; |
| /** maximum number of bytes we'll use for the decode table (to guard against |
| peers ooming us by setting decode table size high) */ |
| uint32_t max_usable_size; |
| /* one before the lowest usable table index */ |
| uint32_t tail_remote_index; |
| uint32_t table_size; |
| uint32_t table_elems; |
| |
| /* filter tables for elems: this tables provides an approximate |
| popularity count for particular hashes, and are used to determine whether |
| a new literal should be added to the compression table or not. |
| They track a single integer that counts how often a particular value has |
| been seen. When that count reaches max (255), all values are halved. */ |
| uint8_t filter_elems[GRPC_CHTTP2_HPACKC_NUM_FILTERS]; |
| |
| /* entry tables for keys & elems: these tables track values that have been |
| seen and *may* be in the decompressor table */ |
| grpc_mdstr *entries_keys[GRPC_CHTTP2_HPACKC_NUM_VALUES]; |
| grpc_mdelem *entries_elems[GRPC_CHTTP2_HPACKC_NUM_VALUES]; |
| uint32_t indices_keys[GRPC_CHTTP2_HPACKC_NUM_VALUES]; |
| uint32_t indices_elems[GRPC_CHTTP2_HPACKC_NUM_VALUES]; |
| |
| uint16_t *table_elem_size; |
| } grpc_chttp2_hpack_compressor; |
| |
| void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c); |
| void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c); |
| void grpc_chttp2_hpack_compressor_set_max_table_size( |
| grpc_chttp2_hpack_compressor *c, uint32_t max_table_size); |
| void grpc_chttp2_hpack_compressor_set_max_usable_size( |
| grpc_chttp2_hpack_compressor *c, uint32_t max_table_size); |
| |
| void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c, uint32_t id, |
| grpc_metadata_batch *metadata, int is_eof, |
| gpr_slice_buffer *outbuf); |
| |
| #endif /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_ENCODER_H */ |