| /* |
| * |
| * Copyright 2015-2016, 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. |
| * |
| */ |
| |
| #include "src/core/transport/chttp2/hpack_encoder.h" |
| |
| #include <assert.h> |
| #include <string.h> |
| |
| /* This is here for grpc_is_binary_header |
| * TODO(murgatroid99): Remove this |
| */ |
| #include <grpc/grpc.h> |
| |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/useful.h> |
| |
| #include "src/core/transport/chttp2/bin_encoder.h" |
| #include "src/core/transport/chttp2/hpack_table.h" |
| #include "src/core/transport/chttp2/timeout_encoding.h" |
| #include "src/core/transport/chttp2/varint.h" |
| #include "src/core/transport/static_metadata.h" |
| |
| #define HASH_FRAGMENT_1(x) ((x)&255) |
| #define HASH_FRAGMENT_2(x) ((x >> 8) & 255) |
| #define HASH_FRAGMENT_3(x) ((x >> 16) & 255) |
| #define HASH_FRAGMENT_4(x) ((x >> 24) & 255) |
| |
| /* if the probability of this item being seen again is < 1/x then don't add |
| it to the table */ |
| #define ONE_ON_ADD_PROBABILITY 128 |
| /* don't consider adding anything bigger than this to the hpack table */ |
| #define MAX_DECODER_SPACE_USAGE 512 |
| |
| typedef struct { |
| int is_first_frame; |
| /* number of bytes in 'output' when we started the frame - used to calculate |
| frame length */ |
| size_t output_length_at_start_of_frame; |
| /* index (in output) of the header for the current frame */ |
| size_t header_idx; |
| /* have we seen a regular (non-colon-prefixed) header yet? */ |
| uint8_t seen_regular_header; |
| /* output stream id */ |
| uint32_t stream_id; |
| gpr_slice_buffer *output; |
| } framer_state; |
| |
| /* fills p (which is expected to be 9 bytes long) with a data frame header */ |
| static void fill_header(uint8_t *p, uint8_t type, uint32_t id, size_t len, |
| uint8_t flags) { |
| GPR_ASSERT(len < 16777316); |
| *p++ = (uint8_t)(len >> 16); |
| *p++ = (uint8_t)(len >> 8); |
| *p++ = (uint8_t)(len); |
| *p++ = type; |
| *p++ = flags; |
| *p++ = (uint8_t)(id >> 24); |
| *p++ = (uint8_t)(id >> 16); |
| *p++ = (uint8_t)(id >> 8); |
| *p++ = (uint8_t)(id); |
| } |
| |
| /* finish a frame - fill in the previously reserved header */ |
| static void finish_frame(framer_state *st, int is_header_boundary, |
| int is_last_in_stream) { |
| uint8_t type = 0xff; |
| type = st->is_first_frame ? GRPC_CHTTP2_FRAME_HEADER |
| : GRPC_CHTTP2_FRAME_CONTINUATION; |
| fill_header( |
| GPR_SLICE_START_PTR(st->output->slices[st->header_idx]), type, |
| st->stream_id, st->output->length - st->output_length_at_start_of_frame, |
| (uint8_t)((is_last_in_stream ? GRPC_CHTTP2_DATA_FLAG_END_STREAM : 0) | |
| (is_header_boundary ? GRPC_CHTTP2_DATA_FLAG_END_HEADERS : 0))); |
| st->is_first_frame = 0; |
| } |
| |
| /* begin a new frame: reserve off header space, remember how many bytes we'd |
| output before beginning */ |
| static void begin_frame(framer_state *st) { |
| st->header_idx = |
| gpr_slice_buffer_add_indexed(st->output, gpr_slice_malloc(9)); |
| st->output_length_at_start_of_frame = st->output->length; |
| } |
| |
| /* make sure that the current frame is of the type desired, and has sufficient |
| space to add at least about_to_add bytes -- finishes the current frame if |
| needed */ |
| static void ensure_space(framer_state *st, size_t need_bytes) { |
| if (st->output->length - st->output_length_at_start_of_frame + need_bytes <= |
| GRPC_CHTTP2_MAX_PAYLOAD_LENGTH) { |
| return; |
| } |
| finish_frame(st, 0, 0); |
| begin_frame(st); |
| } |
| |
| /* increment a filter count, halve all counts if one element reaches max */ |
| static void inc_filter(uint8_t idx, uint32_t *sum, uint8_t *elems) { |
| elems[idx]++; |
| if (elems[idx] < 255) { |
| (*sum)++; |
| } else { |
| int i; |
| *sum = 0; |
| for (i = 0; i < GRPC_CHTTP2_HPACKC_NUM_FILTERS; i++) { |
| elems[i] /= 2; |
| (*sum) += elems[i]; |
| } |
| } |
| } |
| |
| static void add_header_data(framer_state *st, gpr_slice slice) { |
| size_t len = GPR_SLICE_LENGTH(slice); |
| size_t remaining; |
| if (len == 0) return; |
| remaining = GRPC_CHTTP2_MAX_PAYLOAD_LENGTH + |
| st->output_length_at_start_of_frame - st->output->length; |
| if (len <= remaining) { |
| gpr_slice_buffer_add(st->output, slice); |
| } else { |
| gpr_slice_buffer_add(st->output, gpr_slice_split_head(&slice, remaining)); |
| finish_frame(st, 0, 0); |
| begin_frame(st); |
| add_header_data(st, slice); |
| } |
| } |
| |
| static uint8_t *add_tiny_header_data(framer_state *st, size_t len) { |
| ensure_space(st, len); |
| return gpr_slice_buffer_tiny_add(st->output, len); |
| } |
| |
| static void evict_entry(grpc_chttp2_hpack_compressor *c) { |
| c->tail_remote_index++; |
| GPR_ASSERT(c->tail_remote_index > 0); |
| GPR_ASSERT(c->table_size >= |
| c->table_elem_size[c->tail_remote_index % c->cap_table_elems]); |
| GPR_ASSERT(c->table_elems > 0); |
| c->table_size = |
| (uint16_t)(c->table_size - |
| c->table_elem_size[c->tail_remote_index % c->cap_table_elems]); |
| c->table_elems--; |
| } |
| |
| /* add an element to the decoder table */ |
| static void add_elem(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem) { |
| uint32_t key_hash = elem->key->hash; |
| uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash); |
| uint32_t new_index = c->tail_remote_index + c->table_elems + 1; |
| size_t elem_size = 32 + GPR_SLICE_LENGTH(elem->key->slice) + |
| GPR_SLICE_LENGTH(elem->value->slice); |
| |
| GPR_ASSERT(elem_size < 65536); |
| |
| if (elem_size > c->max_table_size) { |
| while (c->table_size > 0) { |
| evict_entry(c); |
| } |
| return; |
| } |
| |
| /* Reserve space for this element in the remote table: if this overflows |
| the current table, drop elements until it fits, matching the decompressor |
| algorithm */ |
| while (c->table_size + elem_size > c->max_table_size) { |
| evict_entry(c); |
| } |
| GPR_ASSERT(c->table_elems < c->max_table_size); |
| c->table_elem_size[new_index % c->cap_table_elems] = (uint16_t)elem_size; |
| c->table_size = (uint16_t)(c->table_size + elem_size); |
| c->table_elems++; |
| |
| /* Store this element into {entries,indices}_elem */ |
| if (c->entries_elems[HASH_FRAGMENT_2(elem_hash)] == elem) { |
| /* already there: update with new index */ |
| c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index; |
| } else if (c->entries_elems[HASH_FRAGMENT_3(elem_hash)] == elem) { |
| /* already there (cuckoo): update with new index */ |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index; |
| } else if (c->entries_elems[HASH_FRAGMENT_2(elem_hash)] == NULL) { |
| /* not there, but a free element: add */ |
| c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem); |
| c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index; |
| } else if (c->entries_elems[HASH_FRAGMENT_3(elem_hash)] == NULL) { |
| /* not there (cuckoo), but a free element: add */ |
| c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem); |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index; |
| } else if (c->indices_elems[HASH_FRAGMENT_2(elem_hash)] < |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)]) { |
| /* not there: replace oldest */ |
| GRPC_MDELEM_UNREF(c->entries_elems[HASH_FRAGMENT_2(elem_hash)]); |
| c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = GRPC_MDELEM_REF(elem); |
| c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index; |
| } else { |
| /* not there: replace oldest */ |
| GRPC_MDELEM_UNREF(c->entries_elems[HASH_FRAGMENT_3(elem_hash)]); |
| c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = GRPC_MDELEM_REF(elem); |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index; |
| } |
| |
| /* do exactly the same for the key (so we can find by that again too) */ |
| |
| if (c->entries_keys[HASH_FRAGMENT_2(key_hash)] == elem->key) { |
| c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index; |
| } else if (c->entries_keys[HASH_FRAGMENT_3(key_hash)] == elem->key) { |
| c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index; |
| } else if (c->entries_keys[HASH_FRAGMENT_2(key_hash)] == NULL) { |
| c->entries_keys[HASH_FRAGMENT_2(key_hash)] = GRPC_MDSTR_REF(elem->key); |
| c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index; |
| } else if (c->entries_keys[HASH_FRAGMENT_3(key_hash)] == NULL) { |
| c->entries_keys[HASH_FRAGMENT_3(key_hash)] = GRPC_MDSTR_REF(elem->key); |
| c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index; |
| } else if (c->indices_keys[HASH_FRAGMENT_2(key_hash)] < |
| c->indices_keys[HASH_FRAGMENT_3(key_hash)]) { |
| GRPC_MDSTR_UNREF(c->entries_keys[HASH_FRAGMENT_2(key_hash)]); |
| c->entries_keys[HASH_FRAGMENT_2(key_hash)] = GRPC_MDSTR_REF(elem->key); |
| c->indices_keys[HASH_FRAGMENT_2(key_hash)] = new_index; |
| } else { |
| GRPC_MDSTR_UNREF(c->entries_keys[HASH_FRAGMENT_3(key_hash)]); |
| c->entries_keys[HASH_FRAGMENT_3(key_hash)] = GRPC_MDSTR_REF(elem->key); |
| c->indices_keys[HASH_FRAGMENT_3(key_hash)] = new_index; |
| } |
| } |
| |
| static void emit_indexed(grpc_chttp2_hpack_compressor *c, uint32_t elem_index, |
| framer_state *st) { |
| uint32_t len = GRPC_CHTTP2_VARINT_LENGTH(elem_index, 1); |
| GRPC_CHTTP2_WRITE_VARINT(elem_index, 1, 0x80, add_tiny_header_data(st, len), |
| len); |
| } |
| |
| static gpr_slice get_wire_value(grpc_mdelem *elem, uint8_t *huffman_prefix) { |
| if (grpc_is_binary_header((const char *)GPR_SLICE_START_PTR(elem->key->slice), |
| GPR_SLICE_LENGTH(elem->key->slice))) { |
| *huffman_prefix = 0x80; |
| return grpc_mdstr_as_base64_encoded_and_huffman_compressed(elem->value); |
| } |
| /* TODO(ctiller): opportunistically compress non-binary headers */ |
| *huffman_prefix = 0x00; |
| return elem->value->slice; |
| } |
| |
| static void emit_lithdr_incidx(grpc_chttp2_hpack_compressor *c, |
| uint32_t key_index, grpc_mdelem *elem, |
| framer_state *st) { |
| uint32_t len_pfx = GRPC_CHTTP2_VARINT_LENGTH(key_index, 2); |
| uint8_t huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| size_t len_val = GPR_SLICE_LENGTH(value_slice); |
| uint32_t len_val_len; |
| GPR_ASSERT(len_val <= UINT32_MAX); |
| len_val_len = GRPC_CHTTP2_VARINT_LENGTH((uint32_t)len_val, 1); |
| GRPC_CHTTP2_WRITE_VARINT(key_index, 2, 0x40, |
| add_tiny_header_data(st, len_pfx), len_pfx); |
| GRPC_CHTTP2_WRITE_VARINT((uint32_t)len_val, 1, 0x00, |
| add_tiny_header_data(st, len_val_len), len_val_len); |
| add_header_data(st, gpr_slice_ref(value_slice)); |
| } |
| |
| static void emit_lithdr_noidx(grpc_chttp2_hpack_compressor *c, |
| uint32_t key_index, grpc_mdelem *elem, |
| framer_state *st) { |
| uint32_t len_pfx = GRPC_CHTTP2_VARINT_LENGTH(key_index, 4); |
| uint8_t huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| size_t len_val = GPR_SLICE_LENGTH(value_slice); |
| uint32_t len_val_len; |
| GPR_ASSERT(len_val <= UINT32_MAX); |
| len_val_len = GRPC_CHTTP2_VARINT_LENGTH((uint32_t)len_val, 1); |
| GRPC_CHTTP2_WRITE_VARINT(key_index, 4, 0x00, |
| add_tiny_header_data(st, len_pfx), len_pfx); |
| GRPC_CHTTP2_WRITE_VARINT((uint32_t)len_val, 1, 0x00, |
| add_tiny_header_data(st, len_val_len), len_val_len); |
| add_header_data(st, gpr_slice_ref(value_slice)); |
| } |
| |
| static void emit_lithdr_incidx_v(grpc_chttp2_hpack_compressor *c, |
| grpc_mdelem *elem, framer_state *st) { |
| uint32_t len_key = (uint32_t)GPR_SLICE_LENGTH(elem->key->slice); |
| uint8_t huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| uint32_t len_val = (uint32_t)GPR_SLICE_LENGTH(value_slice); |
| uint32_t len_key_len = GRPC_CHTTP2_VARINT_LENGTH(len_key, 1); |
| uint32_t len_val_len = GRPC_CHTTP2_VARINT_LENGTH(len_val, 1); |
| GPR_ASSERT(len_key <= UINT32_MAX); |
| GPR_ASSERT(GPR_SLICE_LENGTH(value_slice) <= UINT32_MAX); |
| *add_tiny_header_data(st, 1) = 0x40; |
| GRPC_CHTTP2_WRITE_VARINT(len_key, 1, 0x00, |
| add_tiny_header_data(st, len_key_len), len_key_len); |
| add_header_data(st, gpr_slice_ref(elem->key->slice)); |
| GRPC_CHTTP2_WRITE_VARINT(len_val, 1, huffman_prefix, |
| add_tiny_header_data(st, len_val_len), len_val_len); |
| add_header_data(st, gpr_slice_ref(value_slice)); |
| } |
| |
| static void emit_lithdr_noidx_v(grpc_chttp2_hpack_compressor *c, |
| grpc_mdelem *elem, framer_state *st) { |
| uint32_t len_key = (uint32_t)GPR_SLICE_LENGTH(elem->key->slice); |
| uint8_t huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| uint32_t len_val = (uint32_t)GPR_SLICE_LENGTH(value_slice); |
| uint32_t len_key_len = GRPC_CHTTP2_VARINT_LENGTH(len_key, 1); |
| uint32_t len_val_len = GRPC_CHTTP2_VARINT_LENGTH(len_val, 1); |
| GPR_ASSERT(len_key <= UINT32_MAX); |
| GPR_ASSERT(GPR_SLICE_LENGTH(value_slice) <= UINT32_MAX); |
| *add_tiny_header_data(st, 1) = 0x00; |
| GRPC_CHTTP2_WRITE_VARINT(len_key, 1, 0x00, |
| add_tiny_header_data(st, len_key_len), len_key_len); |
| add_header_data(st, gpr_slice_ref(elem->key->slice)); |
| GRPC_CHTTP2_WRITE_VARINT(len_val, 1, huffman_prefix, |
| add_tiny_header_data(st, len_val_len), len_val_len); |
| add_header_data(st, gpr_slice_ref(value_slice)); |
| } |
| |
| static void emit_advertise_table_size_change(grpc_chttp2_hpack_compressor *c, |
| framer_state *st) { |
| uint32_t len = GRPC_CHTTP2_VARINT_LENGTH(c->max_table_size, 3); |
| GRPC_CHTTP2_WRITE_VARINT(c->max_table_size, 3, 0x20, |
| add_tiny_header_data(st, len), len); |
| c->advertise_table_size_change = 0; |
| } |
| |
| static uint32_t dynidx(grpc_chttp2_hpack_compressor *c, uint32_t elem_index) { |
| return 1 + GRPC_CHTTP2_LAST_STATIC_ENTRY + c->tail_remote_index + |
| c->table_elems - elem_index; |
| } |
| |
| /* encode an mdelem */ |
| static void hpack_enc(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem, |
| framer_state *st) { |
| uint32_t key_hash = elem->key->hash; |
| uint32_t elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash); |
| size_t decoder_space_usage; |
| uint32_t indices_key; |
| int should_add_elem; |
| |
| GPR_ASSERT(GPR_SLICE_LENGTH(elem->key->slice) > 0); |
| if (GPR_SLICE_START_PTR(elem->key->slice)[0] != ':') { /* regular header */ |
| st->seen_regular_header = 1; |
| } else { |
| GPR_ASSERT( |
| st->seen_regular_header == 0 && |
| "Reserved header (colon-prefixed) happening after regular ones."); |
| } |
| |
| inc_filter(HASH_FRAGMENT_1(elem_hash), &c->filter_elems_sum, c->filter_elems); |
| |
| /* is this elem currently in the decoders table? */ |
| |
| if (c->entries_elems[HASH_FRAGMENT_2(elem_hash)] == elem && |
| c->indices_elems[HASH_FRAGMENT_2(elem_hash)] > c->tail_remote_index) { |
| /* HIT: complete element (first cuckoo hash) */ |
| emit_indexed(c, dynidx(c, c->indices_elems[HASH_FRAGMENT_2(elem_hash)]), |
| st); |
| return; |
| } |
| |
| if (c->entries_elems[HASH_FRAGMENT_3(elem_hash)] == elem && |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)] > c->tail_remote_index) { |
| /* HIT: complete element (second cuckoo hash) */ |
| emit_indexed(c, dynidx(c, c->indices_elems[HASH_FRAGMENT_3(elem_hash)]), |
| st); |
| return; |
| } |
| |
| /* should this elem be in the table? */ |
| decoder_space_usage = 32 + GPR_SLICE_LENGTH(elem->key->slice) + |
| GPR_SLICE_LENGTH(elem->value->slice); |
| should_add_elem = decoder_space_usage < MAX_DECODER_SPACE_USAGE && |
| c->filter_elems[HASH_FRAGMENT_1(elem_hash)] >= |
| c->filter_elems_sum / ONE_ON_ADD_PROBABILITY; |
| |
| /* no hits for the elem... maybe there's a key? */ |
| |
| indices_key = c->indices_keys[HASH_FRAGMENT_2(key_hash)]; |
| if (c->entries_keys[HASH_FRAGMENT_2(key_hash)] == elem->key && |
| indices_key > c->tail_remote_index) { |
| /* HIT: key (first cuckoo hash) */ |
| if (should_add_elem) { |
| emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st); |
| add_elem(c, elem); |
| return; |
| } else { |
| emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st); |
| return; |
| } |
| GPR_UNREACHABLE_CODE(return ); |
| } |
| |
| indices_key = c->indices_keys[HASH_FRAGMENT_3(key_hash)]; |
| if (c->entries_keys[HASH_FRAGMENT_3(key_hash)] == elem->key && |
| indices_key > c->tail_remote_index) { |
| /* HIT: key (first cuckoo hash) */ |
| if (should_add_elem) { |
| emit_lithdr_incidx(c, dynidx(c, indices_key), elem, st); |
| add_elem(c, elem); |
| return; |
| } else { |
| emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st); |
| return; |
| } |
| GPR_UNREACHABLE_CODE(return ); |
| } |
| |
| /* no elem, key in the table... fall back to literal emission */ |
| |
| if (should_add_elem) { |
| emit_lithdr_incidx_v(c, elem, st); |
| add_elem(c, elem); |
| return; |
| } else { |
| emit_lithdr_noidx_v(c, elem, st); |
| return; |
| } |
| GPR_UNREACHABLE_CODE(return ); |
| } |
| |
| #define STRLEN_LIT(x) (sizeof(x) - 1) |
| #define TIMEOUT_KEY "grpc-timeout" |
| |
| static void deadline_enc(grpc_chttp2_hpack_compressor *c, gpr_timespec deadline, |
| framer_state *st) { |
| char timeout_str[GRPC_CHTTP2_TIMEOUT_ENCODE_MIN_BUFSIZE]; |
| grpc_mdelem *mdelem; |
| grpc_chttp2_encode_timeout( |
| gpr_time_sub(deadline, gpr_now(deadline.clock_type)), timeout_str); |
| mdelem = grpc_mdelem_from_metadata_strings( |
| GRPC_MDSTR_GRPC_TIMEOUT, grpc_mdstr_from_string(timeout_str)); |
| hpack_enc(c, mdelem, st); |
| GRPC_MDELEM_UNREF(mdelem); |
| } |
| |
| static uint32_t elems_for_bytes(uint32_t bytes) { return (bytes + 31) / 32; } |
| |
| void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c) { |
| memset(c, 0, sizeof(*c)); |
| c->max_table_size = GRPC_CHTTP2_HPACKC_INITIAL_TABLE_SIZE; |
| c->cap_table_elems = elems_for_bytes(c->max_table_size); |
| c->max_table_elems = c->cap_table_elems; |
| c->max_usable_size = GRPC_CHTTP2_HPACKC_INITIAL_TABLE_SIZE; |
| c->table_elem_size = |
| gpr_malloc(sizeof(*c->table_elem_size) * c->cap_table_elems); |
| memset(c->table_elem_size, 0, |
| sizeof(*c->table_elem_size) * c->cap_table_elems); |
| } |
| |
| void grpc_chttp2_hpack_compressor_destroy(grpc_chttp2_hpack_compressor *c) { |
| int i; |
| for (i = 0; i < GRPC_CHTTP2_HPACKC_NUM_VALUES; i++) { |
| if (c->entries_keys[i]) GRPC_MDSTR_UNREF(c->entries_keys[i]); |
| if (c->entries_elems[i]) GRPC_MDELEM_UNREF(c->entries_elems[i]); |
| } |
| gpr_free(c->table_elem_size); |
| } |
| |
| void grpc_chttp2_hpack_compressor_set_max_usable_size( |
| grpc_chttp2_hpack_compressor *c, uint32_t max_table_size) { |
| c->max_usable_size = max_table_size; |
| grpc_chttp2_hpack_compressor_set_max_table_size( |
| c, GPR_MIN(c->max_table_size, max_table_size)); |
| } |
| |
| static void rebuild_elems(grpc_chttp2_hpack_compressor *c, uint32_t new_cap) { |
| uint16_t *table_elem_size = gpr_malloc(sizeof(*table_elem_size) * new_cap); |
| uint32_t i; |
| |
| memset(table_elem_size, 0, sizeof(*table_elem_size) * new_cap); |
| GPR_ASSERT(c->table_elems <= new_cap); |
| |
| for (i = 0; i < c->table_elems; i++) { |
| uint32_t ofs = c->tail_remote_index + i + 1; |
| table_elem_size[ofs % new_cap] = |
| c->table_elem_size[ofs % c->cap_table_elems]; |
| } |
| |
| c->cap_table_elems = new_cap; |
| gpr_free(c->table_elem_size); |
| c->table_elem_size = table_elem_size; |
| } |
| |
| void grpc_chttp2_hpack_compressor_set_max_table_size( |
| grpc_chttp2_hpack_compressor *c, uint32_t max_table_size) { |
| max_table_size = GPR_MIN(max_table_size, c->max_usable_size); |
| if (max_table_size == c->max_table_size) { |
| return; |
| } |
| while (c->table_size > 0 && c->table_size > max_table_size) { |
| evict_entry(c); |
| } |
| c->max_table_size = max_table_size; |
| c->max_table_elems = elems_for_bytes(max_table_size); |
| if (c->max_table_elems > c->cap_table_elems) { |
| rebuild_elems(c, GPR_MAX(c->max_table_elems, 2 * c->cap_table_elems)); |
| } else if (c->max_table_elems < c->cap_table_elems / 3) { |
| uint32_t new_cap = GPR_MAX(c->max_table_elems, 16); |
| if (new_cap != c->cap_table_elems) { |
| rebuild_elems(c, new_cap); |
| } |
| } |
| c->advertise_table_size_change = 1; |
| gpr_log(GPR_DEBUG, "set max table size from encoder to %d", max_table_size); |
| } |
| |
| void grpc_chttp2_encode_header(grpc_chttp2_hpack_compressor *c, |
| uint32_t stream_id, |
| grpc_metadata_batch *metadata, int is_eof, |
| gpr_slice_buffer *outbuf) { |
| framer_state st; |
| grpc_linked_mdelem *l; |
| gpr_timespec deadline; |
| |
| GPR_ASSERT(stream_id != 0); |
| |
| st.seen_regular_header = 0; |
| st.stream_id = stream_id; |
| st.output = outbuf; |
| st.is_first_frame = 1; |
| |
| /* Encode a metadata batch; store the returned values, representing |
| a metadata element that needs to be unreffed back into the metadata |
| slot. THIS MAY NOT BE THE SAME ELEMENT (if a decoder table slot got |
| updated). After this loop, we'll do a batch unref of elements. */ |
| begin_frame(&st); |
| if (c->advertise_table_size_change != 0) { |
| emit_advertise_table_size_change(c, &st); |
| } |
| grpc_metadata_batch_assert_ok(metadata); |
| for (l = metadata->list.head; l; l = l->next) { |
| hpack_enc(c, l->md, &st); |
| } |
| deadline = metadata->deadline; |
| if (gpr_time_cmp(deadline, gpr_inf_future(deadline.clock_type)) != 0) { |
| deadline_enc(c, deadline, &st); |
| } |
| |
| finish_frame(&st, 1, is_eof); |
| } |