| /* |
| * |
| * 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. |
| * |
| */ |
| |
| #include "src/core/transport/chttp2/stream_encoder.h" |
| |
| #include <assert.h> |
| #include <string.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" |
| |
| #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 |
| |
| /* what kind of frame our we encoding? */ |
| typedef enum { HEADER, DATA, NONE } frame_type; |
| |
| typedef struct { |
| frame_type cur_frame_type; |
| /* 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; |
| /* was the last frame emitted a header? (if yes, we'll need a CONTINUATION */ |
| gpr_uint8 last_was_header; |
| /* output stream id */ |
| gpr_uint32 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(gpr_uint8 *p, gpr_uint8 type, gpr_uint32 id, |
| gpr_uint32 len, gpr_uint8 flags) { |
| *p++ = len >> 16; |
| *p++ = len >> 8; |
| *p++ = len; |
| *p++ = type; |
| *p++ = flags; |
| *p++ = id >> 24; |
| *p++ = id >> 16; |
| *p++ = id >> 8; |
| *p++ = 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) { |
| gpr_uint8 type = 0xff; |
| switch (st->cur_frame_type) { |
| case HEADER: |
| type = st->last_was_header ? GRPC_CHTTP2_FRAME_CONTINUATION |
| : GRPC_CHTTP2_FRAME_HEADER; |
| st->last_was_header = 1; |
| break; |
| case DATA: |
| type = GRPC_CHTTP2_FRAME_DATA; |
| st->last_was_header = 0; |
| is_header_boundary = 0; |
| break; |
| case NONE: |
| return; |
| } |
| 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, |
| (is_last_in_stream ? GRPC_CHTTP2_DATA_FLAG_END_STREAM : 0) | |
| (is_header_boundary ? GRPC_CHTTP2_DATA_FLAG_END_HEADERS : 0)); |
| st->cur_frame_type = NONE; |
| } |
| |
| /* begin a new frame: reserve off header space, remember how many bytes we'd |
| output before beginning */ |
| static void begin_frame(framer_state *st, frame_type type) { |
| GPR_ASSERT(type != NONE); |
| GPR_ASSERT(st->cur_frame_type == NONE); |
| st->cur_frame_type = type; |
| 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_frame_type(framer_state *st, frame_type type, |
| int need_bytes) { |
| if (st->cur_frame_type == type && |
| st->output->length - st->output_length_at_start_of_frame + need_bytes <= |
| GRPC_CHTTP2_MAX_PAYLOAD_LENGTH) { |
| return; |
| } |
| finish_frame(st, type != HEADER, 0); |
| begin_frame(st, type); |
| } |
| |
| /* increment a filter count, halve all counts if one element reaches max */ |
| static void inc_filter(gpr_uint8 idx, gpr_uint32 *sum, gpr_uint8 *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; |
| ensure_frame_type(st, HEADER, 1); |
| 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)); |
| add_header_data(st, slice); |
| } |
| } |
| |
| static gpr_uint8 *add_tiny_header_data(framer_state *st, int len) { |
| ensure_frame_type(st, HEADER, len); |
| return gpr_slice_buffer_tiny_add(st->output, len); |
| } |
| |
| /* add an element to the decoder table: returns metadata element to unref */ |
| static grpc_mdelem *add_elem(grpc_chttp2_hpack_compressor *c, |
| grpc_mdelem *elem) { |
| gpr_uint32 key_hash = elem->key->hash; |
| gpr_uint32 elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash); |
| gpr_uint32 new_index = c->tail_remote_index + c->table_elems + 1; |
| gpr_uint32 elem_size = 32 + GPR_SLICE_LENGTH(elem->key->slice) + |
| GPR_SLICE_LENGTH(elem->value->slice); |
| grpc_mdelem *elem_to_unref; |
| |
| /* Reserve space for this element in the remote table: if this overflows |
| the current table, drop elements until it fits, matching the decompressor |
| algorithm */ |
| /* TODO(ctiller): constant */ |
| while (c->table_size + elem_size > 4096) { |
| c->tail_remote_index++; |
| GPR_ASSERT(c->tail_remote_index > 0); |
| GPR_ASSERT(c->table_size >= |
| c->table_elem_size[c->tail_remote_index % |
| GRPC_CHTTP2_HPACKC_MAX_TABLE_ELEMS]); |
| GPR_ASSERT(c->table_elems > 0); |
| c->table_size -= c->table_elem_size[c->tail_remote_index % |
| GRPC_CHTTP2_HPACKC_MAX_TABLE_ELEMS]; |
| c->table_elems--; |
| } |
| GPR_ASSERT(c->table_elems < GRPC_CHTTP2_HPACKC_MAX_TABLE_ELEMS); |
| c->table_elem_size[new_index % GRPC_CHTTP2_HPACKC_MAX_TABLE_ELEMS] = |
| elem_size; |
| 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; |
| elem_to_unref = elem; |
| } 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; |
| elem_to_unref = elem; |
| } 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)] = elem; |
| c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index; |
| elem_to_unref = NULL; |
| } 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)] = elem; |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)] = new_index; |
| elem_to_unref = NULL; |
| } else if (c->indices_elems[HASH_FRAGMENT_2(elem_hash)] < |
| c->indices_elems[HASH_FRAGMENT_3(elem_hash)]) { |
| /* not there: replace oldest */ |
| elem_to_unref = c->entries_elems[HASH_FRAGMENT_2(elem_hash)]; |
| c->entries_elems[HASH_FRAGMENT_2(elem_hash)] = elem; |
| c->indices_elems[HASH_FRAGMENT_2(elem_hash)] = new_index; |
| } else { |
| /* not there: replace oldest */ |
| elem_to_unref = c->entries_elems[HASH_FRAGMENT_3(elem_hash)]; |
| c->entries_elems[HASH_FRAGMENT_3(elem_hash)] = 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; |
| } |
| |
| return elem_to_unref; |
| } |
| |
| static void emit_indexed(grpc_chttp2_hpack_compressor *c, gpr_uint32 index, |
| framer_state *st) { |
| int len = GRPC_CHTTP2_VARINT_LENGTH(index, 1); |
| GRPC_CHTTP2_WRITE_VARINT(index, 1, 0x80, add_tiny_header_data(st, len), len); |
| } |
| |
| static gpr_slice get_wire_value(grpc_mdelem *elem, gpr_uint8 *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, |
| gpr_uint32 key_index, grpc_mdelem *elem, |
| framer_state *st) { |
| int len_pfx = GRPC_CHTTP2_VARINT_LENGTH(key_index, 2); |
| gpr_uint8 huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| int len_val = GPR_SLICE_LENGTH(value_slice); |
| int len_val_len = GRPC_CHTTP2_VARINT_LENGTH(len_val, 1); |
| GRPC_CHTTP2_WRITE_VARINT(key_index, 2, 0x40, |
| add_tiny_header_data(st, len_pfx), len_pfx); |
| GRPC_CHTTP2_WRITE_VARINT(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, |
| gpr_uint32 key_index, grpc_mdelem *elem, |
| framer_state *st) { |
| int len_pfx = GRPC_CHTTP2_VARINT_LENGTH(key_index, 4); |
| gpr_uint8 huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| int len_val = GPR_SLICE_LENGTH(value_slice); |
| int len_val_len = GRPC_CHTTP2_VARINT_LENGTH(len_val, 1); |
| GRPC_CHTTP2_WRITE_VARINT(key_index, 4, 0x00, |
| add_tiny_header_data(st, len_pfx), len_pfx); |
| GRPC_CHTTP2_WRITE_VARINT(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) { |
| int len_key = GPR_SLICE_LENGTH(elem->key->slice); |
| gpr_uint8 huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| int len_val = GPR_SLICE_LENGTH(value_slice); |
| int len_key_len = GRPC_CHTTP2_VARINT_LENGTH(len_key, 1); |
| int len_val_len = GRPC_CHTTP2_VARINT_LENGTH(len_val, 1); |
| *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) { |
| int len_key = GPR_SLICE_LENGTH(elem->key->slice); |
| gpr_uint8 huffman_prefix; |
| gpr_slice value_slice = get_wire_value(elem, &huffman_prefix); |
| int len_val = GPR_SLICE_LENGTH(value_slice); |
| int len_key_len = GRPC_CHTTP2_VARINT_LENGTH(len_key, 1); |
| int len_val_len = GRPC_CHTTP2_VARINT_LENGTH(len_val, 1); |
| *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 gpr_uint32 dynidx(grpc_chttp2_hpack_compressor *c, gpr_uint32 index) { |
| return 1 + GRPC_CHTTP2_LAST_STATIC_ENTRY + c->tail_remote_index + |
| c->table_elems - index; |
| } |
| |
| /* encode an mdelem; returns metadata element to unref */ |
| static grpc_mdelem *hpack_enc(grpc_chttp2_hpack_compressor *c, |
| grpc_mdelem *elem, framer_state *st) { |
| gpr_uint32 key_hash = elem->key->hash; |
| gpr_uint32 elem_hash = GRPC_MDSTR_KV_HASH(key_hash, elem->value->hash); |
| size_t decoder_space_usage; |
| gpr_uint32 indices_key; |
| int should_add_elem; |
| |
| 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 elem; |
| } |
| |
| 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 elem; |
| } |
| |
| /* 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); |
| return add_elem(c, elem); |
| } else { |
| emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st); |
| return elem; |
| } |
| abort(); |
| } |
| |
| 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); |
| return add_elem(c, elem); |
| } else { |
| emit_lithdr_noidx(c, dynidx(c, indices_key), elem, st); |
| return elem; |
| } |
| abort(); |
| } |
| |
| /* no elem, key in the table... fall back to literal emission */ |
| |
| if (should_add_elem) { |
| emit_lithdr_incidx_v(c, elem, st); |
| return add_elem(c, elem); |
| } else { |
| emit_lithdr_noidx_v(c, elem, st); |
| return elem; |
| } |
| abort(); |
| } |
| |
| #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()), timeout_str); |
| mdelem = grpc_mdelem_from_metadata_strings( |
| c->mdctx, grpc_mdstr_ref(c->timeout_key_str), |
| grpc_mdstr_from_string(c->mdctx, timeout_str)); |
| mdelem = hpack_enc(c, mdelem, st); |
| if (mdelem) grpc_mdelem_unref(mdelem); |
| } |
| |
| gpr_slice grpc_chttp2_data_frame_create_empty_close(gpr_uint32 id) { |
| gpr_slice slice = gpr_slice_malloc(9); |
| fill_header(GPR_SLICE_START_PTR(slice), GRPC_CHTTP2_FRAME_DATA, id, 0, 1); |
| return slice; |
| } |
| |
| void grpc_chttp2_hpack_compressor_init(grpc_chttp2_hpack_compressor *c, |
| grpc_mdctx *ctx) { |
| memset(c, 0, sizeof(*c)); |
| c->mdctx = ctx; |
| c->timeout_key_str = grpc_mdstr_from_string(ctx, "grpc-timeout"); |
| } |
| |
| 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]); |
| } |
| grpc_mdstr_unref(c->timeout_key_str); |
| } |
| |
| gpr_uint32 grpc_chttp2_preencode(grpc_stream_op *inops, size_t *inops_count, |
| gpr_uint32 max_flow_controlled_bytes, |
| grpc_stream_op_buffer *outops) { |
| gpr_slice slice; |
| grpc_stream_op *op; |
| gpr_uint32 max_take_size; |
| gpr_uint32 flow_controlled_bytes_taken = 0; |
| gpr_uint32 curop = 0; |
| gpr_uint8 *p; |
| |
| while (curop < *inops_count) { |
| GPR_ASSERT(flow_controlled_bytes_taken <= max_flow_controlled_bytes); |
| op = &inops[curop]; |
| switch (op->type) { |
| case GRPC_NO_OP: |
| /* skip */ |
| curop++; |
| break; |
| case GRPC_OP_METADATA: |
| grpc_metadata_batch_assert_ok(&op->data.metadata); |
| case GRPC_OP_FLOW_CTL_CB: |
| /* these just get copied as they don't impact the number of flow |
| controlled bytes */ |
| grpc_sopb_append(outops, op, 1); |
| curop++; |
| break; |
| case GRPC_OP_BEGIN_MESSAGE: |
| /* begin op: for now we just convert the op to a slice and fall |
| through - this lets us reuse the slice framing code below */ |
| slice = gpr_slice_malloc(5); |
| p = GPR_SLICE_START_PTR(slice); |
| p[0] = 0; |
| p[1] = op->data.begin_message.length >> 24; |
| p[2] = op->data.begin_message.length >> 16; |
| p[3] = op->data.begin_message.length >> 8; |
| p[4] = op->data.begin_message.length; |
| op->type = GRPC_OP_SLICE; |
| op->data.slice = slice; |
| /* fallthrough */ |
| case GRPC_OP_SLICE: |
| slice = op->data.slice; |
| if (!GPR_SLICE_LENGTH(slice)) { |
| /* skip zero length slices */ |
| gpr_slice_unref(slice); |
| curop++; |
| break; |
| } |
| max_take_size = max_flow_controlled_bytes - flow_controlled_bytes_taken; |
| if (max_take_size == 0) { |
| goto exit_loop; |
| } |
| if (GPR_SLICE_LENGTH(slice) > max_take_size) { |
| slice = gpr_slice_split_head(&op->data.slice, max_take_size); |
| grpc_sopb_add_slice(outops, slice); |
| } else { |
| /* consume this op immediately */ |
| grpc_sopb_append(outops, op, 1); |
| curop++; |
| } |
| flow_controlled_bytes_taken += GPR_SLICE_LENGTH(slice); |
| break; |
| } |
| } |
| exit_loop: |
| *inops_count -= curop; |
| memmove(inops, inops + curop, *inops_count * sizeof(grpc_stream_op)); |
| |
| for (curop = 0; curop < *inops_count; curop++) { |
| if (inops[curop].type == GRPC_OP_METADATA) { |
| grpc_metadata_batch_assert_ok(&inops[curop].data.metadata); |
| } |
| } |
| |
| return flow_controlled_bytes_taken; |
| } |
| |
| void grpc_chttp2_encode(grpc_stream_op *ops, size_t ops_count, int eof, |
| gpr_uint32 stream_id, |
| grpc_chttp2_hpack_compressor *compressor, |
| gpr_slice_buffer *output) { |
| framer_state st; |
| gpr_slice slice; |
| grpc_stream_op *op; |
| gpr_uint32 max_take_size; |
| gpr_uint32 curop = 0; |
| gpr_uint32 unref_op; |
| grpc_mdctx *mdctx = compressor->mdctx; |
| grpc_linked_mdelem *l; |
| int need_unref = 0; |
| |
| GPR_ASSERT(stream_id != 0); |
| |
| st.cur_frame_type = NONE; |
| st.last_was_header = 0; |
| st.stream_id = stream_id; |
| st.output = output; |
| |
| while (curop < ops_count) { |
| op = &ops[curop]; |
| switch (op->type) { |
| case GRPC_NO_OP: |
| case GRPC_OP_BEGIN_MESSAGE: |
| gpr_log( |
| GPR_ERROR, |
| "These stream ops should be filtered out by grpc_chttp2_preencode"); |
| abort(); |
| case GRPC_OP_FLOW_CTL_CB: |
| op->data.flow_ctl_cb.cb(op->data.flow_ctl_cb.arg, GRPC_OP_OK); |
| curop++; |
| break; |
| case GRPC_OP_METADATA: |
| /* 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. */ |
| need_unref |= op->data.metadata.garbage.head != NULL; |
| grpc_metadata_batch_assert_ok(&op->data.metadata); |
| for (l = op->data.metadata.list.head; l; l = l->next) { |
| l->md = hpack_enc(compressor, l->md, &st); |
| need_unref |= l->md != NULL; |
| } |
| if (gpr_time_cmp(op->data.metadata.deadline, gpr_inf_future) != 0) { |
| deadline_enc(compressor, op->data.metadata.deadline, &st); |
| } |
| ensure_frame_type(&st, HEADER, 0); |
| finish_frame(&st, 1, 0); |
| st.last_was_header = 0; /* force a new header frame */ |
| curop++; |
| break; |
| case GRPC_OP_SLICE: |
| slice = op->data.slice; |
| if (st.cur_frame_type == DATA && |
| st.output->length - st.output_length_at_start_of_frame == |
| GRPC_CHTTP2_MAX_PAYLOAD_LENGTH) { |
| finish_frame(&st, 0, 0); |
| } |
| ensure_frame_type(&st, DATA, 1); |
| max_take_size = GRPC_CHTTP2_MAX_PAYLOAD_LENGTH + |
| st.output_length_at_start_of_frame - st.output->length; |
| if (GPR_SLICE_LENGTH(slice) > max_take_size) { |
| slice = gpr_slice_split_head(&op->data.slice, max_take_size); |
| } else { |
| /* consume this op immediately */ |
| curop++; |
| } |
| gpr_slice_buffer_add(output, slice); |
| break; |
| } |
| } |
| if (eof && st.cur_frame_type == NONE) { |
| begin_frame(&st, DATA); |
| } |
| finish_frame(&st, 1, eof); |
| |
| if (need_unref) { |
| grpc_mdctx_lock(mdctx); |
| for (unref_op = 0; unref_op < curop; unref_op++) { |
| op = &ops[unref_op]; |
| if (op->type != GRPC_OP_METADATA) continue; |
| for (l = op->data.metadata.list.head; l; l = l->next) { |
| if (l->md) grpc_mdctx_locked_mdelem_unref(mdctx, l->md); |
| } |
| for (l = op->data.metadata.garbage.head; l; l = l->next) { |
| grpc_mdctx_locked_mdelem_unref(mdctx, l->md); |
| } |
| } |
| grpc_mdctx_unlock(mdctx); |
| } |
| } |