| /* |
| * |
| * 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 <assert.h> |
| #include <string.h> |
| |
| #include <grpc/compression.h> |
| #include <grpc/slice_buffer.h> |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| |
| #include "src/core/ext/filters/http/message_compress/message_compress_filter.h" |
| #include "src/core/lib/channel/channel_args.h" |
| #include "src/core/lib/compression/algorithm_metadata.h" |
| #include "src/core/lib/compression/message_compress.h" |
| #include "src/core/lib/profiling/timers.h" |
| #include "src/core/lib/slice/slice_internal.h" |
| #include "src/core/lib/slice/slice_string_helpers.h" |
| #include "src/core/lib/support/string.h" |
| #include "src/core/lib/surface/call.h" |
| #include "src/core/lib/transport/static_metadata.h" |
| |
| #define INITIAL_METADATA_UNSEEN 0 |
| #define HAS_COMPRESSION_ALGORITHM 2 |
| #define NO_COMPRESSION_ALGORITHM 4 |
| |
| #define CANCELLED_BIT ((gpr_atm)1) |
| |
| typedef struct call_data { |
| grpc_slice_buffer slices; /**< Buffers up input slices to be compressed */ |
| grpc_linked_mdelem compression_algorithm_storage; |
| grpc_linked_mdelem accept_encoding_storage; |
| uint32_t remaining_slice_bytes; |
| /** Compression algorithm we'll try to use. It may be given by incoming |
| * metadata, or by the channel's default compression settings. */ |
| grpc_compression_algorithm compression_algorithm; |
| |
| /* Atomic recording the state of initial metadata; allowed values: |
| INITIAL_METADATA_UNSEEN - initial metadata op not seen |
| HAS_COMPRESSION_ALGORITHM - initial metadata seen; compression algorithm |
| set |
| NO_COMPRESSION_ALGORITHM - initial metadata seen; no compression algorithm |
| set |
| pointer - a stalled op containing a send_message that's waiting on initial |
| metadata |
| pointer | CANCELLED_BIT - request was cancelled with error pointed to */ |
| gpr_atm send_initial_metadata_state; |
| |
| grpc_transport_stream_op_batch *send_op; |
| uint32_t send_length; |
| uint32_t send_flags; |
| grpc_slice incoming_slice; |
| grpc_slice_buffer_stream replacement_stream; |
| grpc_closure *post_send; |
| grpc_closure send_done; |
| grpc_closure got_slice; |
| } call_data; |
| |
| typedef struct channel_data { |
| /** The default, channel-level, compression algorithm */ |
| grpc_compression_algorithm default_compression_algorithm; |
| /** Bitset of enabled algorithms */ |
| uint32_t enabled_algorithms_bitset; |
| /** Supported compression algorithms */ |
| uint32_t supported_compression_algorithms; |
| } channel_data; |
| |
| static bool skip_compression(grpc_call_element *elem, uint32_t flags, |
| bool has_compression_algorithm) { |
| call_data *calld = elem->call_data; |
| channel_data *channeld = elem->channel_data; |
| |
| if (flags & (GRPC_WRITE_NO_COMPRESS | GRPC_WRITE_INTERNAL_COMPRESS)) { |
| return 1; |
| } |
| if (has_compression_algorithm) { |
| if (calld->compression_algorithm == GRPC_COMPRESS_NONE) { |
| return 1; |
| } |
| return 0; /* we have an actual call-specific algorithm */ |
| } |
| /* no per-call compression override */ |
| return channeld->default_compression_algorithm == GRPC_COMPRESS_NONE; |
| } |
| |
| /** Filter initial metadata */ |
| static grpc_error *process_send_initial_metadata( |
| grpc_exec_ctx *exec_ctx, grpc_call_element *elem, |
| grpc_metadata_batch *initial_metadata, |
| bool *has_compression_algorithm) GRPC_MUST_USE_RESULT; |
| static grpc_error *process_send_initial_metadata( |
| grpc_exec_ctx *exec_ctx, grpc_call_element *elem, |
| grpc_metadata_batch *initial_metadata, bool *has_compression_algorithm) { |
| call_data *calld = elem->call_data; |
| channel_data *channeld = elem->channel_data; |
| *has_compression_algorithm = false; |
| /* Parse incoming request for compression. If any, it'll be available |
| * at calld->compression_algorithm */ |
| if (initial_metadata->idx.named.grpc_internal_encoding_request != NULL) { |
| grpc_mdelem md = |
| initial_metadata->idx.named.grpc_internal_encoding_request->md; |
| if (!grpc_compression_algorithm_parse(GRPC_MDVALUE(md), |
| &calld->compression_algorithm)) { |
| char *val = grpc_slice_to_c_string(GRPC_MDVALUE(md)); |
| gpr_log(GPR_ERROR, |
| "Invalid compression algorithm: '%s' (unknown). Ignoring.", val); |
| gpr_free(val); |
| calld->compression_algorithm = GRPC_COMPRESS_NONE; |
| } |
| if (!GPR_BITGET(channeld->enabled_algorithms_bitset, |
| calld->compression_algorithm)) { |
| char *val = grpc_slice_to_c_string(GRPC_MDVALUE(md)); |
| gpr_log(GPR_ERROR, |
| "Invalid compression algorithm: '%s' (previously disabled). " |
| "Ignoring.", |
| val); |
| gpr_free(val); |
| calld->compression_algorithm = GRPC_COMPRESS_NONE; |
| } |
| *has_compression_algorithm = true; |
| |
| grpc_metadata_batch_remove( |
| exec_ctx, initial_metadata, |
| initial_metadata->idx.named.grpc_internal_encoding_request); |
| } else { |
| /* If no algorithm was found in the metadata and we aren't |
| * exceptionally skipping compression, fall back to the channel |
| * default */ |
| calld->compression_algorithm = channeld->default_compression_algorithm; |
| *has_compression_algorithm = true; |
| } |
| |
| grpc_error *error = GRPC_ERROR_NONE; |
| /* hint compression algorithm */ |
| if (calld->compression_algorithm != GRPC_COMPRESS_NONE) { |
| error = grpc_metadata_batch_add_tail( |
| exec_ctx, initial_metadata, &calld->compression_algorithm_storage, |
| grpc_compression_encoding_mdelem(calld->compression_algorithm)); |
| } |
| |
| if (error != GRPC_ERROR_NONE) return error; |
| |
| /* convey supported compression algorithms */ |
| error = grpc_metadata_batch_add_tail( |
| exec_ctx, initial_metadata, &calld->accept_encoding_storage, |
| GRPC_MDELEM_ACCEPT_ENCODING_FOR_ALGORITHMS( |
| channeld->supported_compression_algorithms)); |
| |
| return error; |
| } |
| |
| static void continue_send_message(grpc_exec_ctx *exec_ctx, |
| grpc_call_element *elem); |
| |
| static void send_done(grpc_exec_ctx *exec_ctx, void *elemp, grpc_error *error) { |
| grpc_call_element *elem = elemp; |
| call_data *calld = elem->call_data; |
| grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &calld->slices); |
| calld->post_send->cb(exec_ctx, calld->post_send->cb_arg, error); |
| } |
| |
| static void finish_send_message(grpc_exec_ctx *exec_ctx, |
| grpc_call_element *elem) { |
| call_data *calld = elem->call_data; |
| int did_compress; |
| grpc_slice_buffer tmp; |
| grpc_slice_buffer_init(&tmp); |
| did_compress = grpc_msg_compress(exec_ctx, calld->compression_algorithm, |
| &calld->slices, &tmp); |
| if (did_compress) { |
| if (GRPC_TRACER_ON(grpc_compression_trace)) { |
| char *algo_name; |
| const size_t before_size = calld->slices.length; |
| const size_t after_size = tmp.length; |
| const float savings_ratio = 1.0f - (float)after_size / (float)before_size; |
| GPR_ASSERT(grpc_compression_algorithm_name(calld->compression_algorithm, |
| &algo_name)); |
| gpr_log(GPR_DEBUG, "Compressed[%s] %" PRIuPTR " bytes vs. %" PRIuPTR |
| " bytes (%.2f%% savings)", |
| algo_name, before_size, after_size, 100 * savings_ratio); |
| } |
| grpc_slice_buffer_swap(&calld->slices, &tmp); |
| calld->send_flags |= GRPC_WRITE_INTERNAL_COMPRESS; |
| } else { |
| if (GRPC_TRACER_ON(grpc_compression_trace)) { |
| char *algo_name; |
| GPR_ASSERT(grpc_compression_algorithm_name(calld->compression_algorithm, |
| &algo_name)); |
| gpr_log(GPR_DEBUG, |
| "Algorithm '%s' enabled but decided not to compress. Input size: " |
| "%" PRIuPTR, |
| algo_name, calld->slices.length); |
| } |
| } |
| |
| grpc_slice_buffer_destroy_internal(exec_ctx, &tmp); |
| |
| grpc_slice_buffer_stream_init(&calld->replacement_stream, &calld->slices, |
| calld->send_flags); |
| calld->send_op->payload->send_message.send_message = |
| &calld->replacement_stream.base; |
| calld->post_send = calld->send_op->on_complete; |
| calld->send_op->on_complete = &calld->send_done; |
| |
| grpc_call_next_op(exec_ctx, elem, calld->send_op); |
| } |
| |
| static void got_slice(grpc_exec_ctx *exec_ctx, void *elemp, grpc_error *error) { |
| grpc_call_element *elem = elemp; |
| call_data *calld = elem->call_data; |
| if (GRPC_ERROR_NONE != |
| grpc_byte_stream_pull(exec_ctx, |
| calld->send_op->payload->send_message.send_message, |
| &calld->incoming_slice)) { |
| /* Should never reach here */ |
| abort(); |
| } |
| grpc_slice_buffer_add(&calld->slices, calld->incoming_slice); |
| if (calld->send_length == calld->slices.length) { |
| finish_send_message(exec_ctx, elem); |
| } else { |
| continue_send_message(exec_ctx, elem); |
| } |
| } |
| |
| static void continue_send_message(grpc_exec_ctx *exec_ctx, |
| grpc_call_element *elem) { |
| call_data *calld = elem->call_data; |
| while (grpc_byte_stream_next( |
| exec_ctx, calld->send_op->payload->send_message.send_message, ~(size_t)0, |
| &calld->got_slice)) { |
| grpc_byte_stream_pull(exec_ctx, |
| calld->send_op->payload->send_message.send_message, |
| &calld->incoming_slice); |
| grpc_slice_buffer_add(&calld->slices, calld->incoming_slice); |
| if (calld->send_length == calld->slices.length) { |
| finish_send_message(exec_ctx, elem); |
| break; |
| } |
| } |
| } |
| |
| static void handle_send_message_batch(grpc_exec_ctx *exec_ctx, |
| grpc_call_element *elem, |
| grpc_transport_stream_op_batch *op, |
| bool has_compression_algorithm) { |
| call_data *calld = elem->call_data; |
| if (!skip_compression(elem, op->payload->send_message.send_message->flags, |
| has_compression_algorithm)) { |
| calld->send_op = op; |
| calld->send_length = op->payload->send_message.send_message->length; |
| calld->send_flags = op->payload->send_message.send_message->flags; |
| continue_send_message(exec_ctx, elem); |
| } else { |
| /* pass control down the stack */ |
| grpc_call_next_op(exec_ctx, elem, op); |
| } |
| } |
| |
| static void compress_start_transport_stream_op_batch( |
| grpc_exec_ctx *exec_ctx, grpc_call_element *elem, |
| grpc_transport_stream_op_batch *op) { |
| call_data *calld = elem->call_data; |
| |
| GPR_TIMER_BEGIN("compress_start_transport_stream_op_batch", 0); |
| |
| if (op->cancel_stream) { |
| GRPC_ERROR_REF(op->payload->cancel_stream.cancel_error); |
| gpr_atm cur = gpr_atm_full_xchg( |
| &calld->send_initial_metadata_state, |
| CANCELLED_BIT | (gpr_atm)op->payload->cancel_stream.cancel_error); |
| switch (cur) { |
| case HAS_COMPRESSION_ALGORITHM: |
| case NO_COMPRESSION_ALGORITHM: |
| case INITIAL_METADATA_UNSEEN: |
| break; |
| default: |
| if ((cur & CANCELLED_BIT) == 0) { |
| grpc_transport_stream_op_batch_finish_with_failure( |
| exec_ctx, (grpc_transport_stream_op_batch *)cur, |
| GRPC_ERROR_REF(op->payload->cancel_stream.cancel_error)); |
| } else { |
| GRPC_ERROR_UNREF((grpc_error *)(cur & ~CANCELLED_BIT)); |
| } |
| break; |
| } |
| } |
| |
| if (op->send_initial_metadata) { |
| bool has_compression_algorithm; |
| grpc_error *error = process_send_initial_metadata( |
| exec_ctx, elem, |
| op->payload->send_initial_metadata.send_initial_metadata, |
| &has_compression_algorithm); |
| if (error != GRPC_ERROR_NONE) { |
| grpc_transport_stream_op_batch_finish_with_failure(exec_ctx, op, error); |
| return; |
| } |
| gpr_atm cur; |
| retry_send_im: |
| cur = gpr_atm_acq_load(&calld->send_initial_metadata_state); |
| GPR_ASSERT(cur != HAS_COMPRESSION_ALGORITHM && |
| cur != NO_COMPRESSION_ALGORITHM); |
| if ((cur & CANCELLED_BIT) == 0) { |
| if (!gpr_atm_rel_cas(&calld->send_initial_metadata_state, cur, |
| has_compression_algorithm |
| ? HAS_COMPRESSION_ALGORITHM |
| : NO_COMPRESSION_ALGORITHM)) { |
| goto retry_send_im; |
| } |
| if (cur != INITIAL_METADATA_UNSEEN) { |
| handle_send_message_batch(exec_ctx, elem, |
| (grpc_transport_stream_op_batch *)cur, |
| has_compression_algorithm); |
| } |
| } |
| } |
| if (op->send_message) { |
| gpr_atm cur; |
| retry_send: |
| cur = gpr_atm_acq_load(&calld->send_initial_metadata_state); |
| switch (cur) { |
| case INITIAL_METADATA_UNSEEN: |
| if (!gpr_atm_rel_cas(&calld->send_initial_metadata_state, cur, |
| (gpr_atm)op)) { |
| goto retry_send; |
| } |
| break; |
| case HAS_COMPRESSION_ALGORITHM: |
| case NO_COMPRESSION_ALGORITHM: |
| handle_send_message_batch(exec_ctx, elem, op, |
| cur == HAS_COMPRESSION_ALGORITHM); |
| break; |
| default: |
| if (cur & CANCELLED_BIT) { |
| grpc_transport_stream_op_batch_finish_with_failure( |
| exec_ctx, op, |
| GRPC_ERROR_REF((grpc_error *)(cur & ~CANCELLED_BIT))); |
| } else { |
| /* >1 send_message concurrently */ |
| GPR_UNREACHABLE_CODE(break); |
| } |
| } |
| } else { |
| /* pass control down the stack */ |
| grpc_call_next_op(exec_ctx, elem, op); |
| } |
| |
| GPR_TIMER_END("compress_start_transport_stream_op_batch", 0); |
| } |
| |
| /* Constructor for call_data */ |
| static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx, |
| grpc_call_element *elem, |
| const grpc_call_element_args *args) { |
| /* grab pointers to our data from the call element */ |
| call_data *calld = elem->call_data; |
| |
| /* initialize members */ |
| grpc_slice_buffer_init(&calld->slices); |
| GRPC_CLOSURE_INIT(&calld->got_slice, got_slice, elem, |
| grpc_schedule_on_exec_ctx); |
| GRPC_CLOSURE_INIT(&calld->send_done, send_done, elem, |
| grpc_schedule_on_exec_ctx); |
| |
| return GRPC_ERROR_NONE; |
| } |
| |
| /* Destructor for call_data */ |
| static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem, |
| const grpc_call_final_info *final_info, |
| grpc_closure *ignored) { |
| /* grab pointers to our data from the call element */ |
| call_data *calld = elem->call_data; |
| grpc_slice_buffer_destroy_internal(exec_ctx, &calld->slices); |
| gpr_atm imstate = |
| gpr_atm_no_barrier_load(&calld->send_initial_metadata_state); |
| if (imstate & CANCELLED_BIT) { |
| GRPC_ERROR_UNREF((grpc_error *)(imstate & ~CANCELLED_BIT)); |
| } |
| } |
| |
| /* Constructor for channel_data */ |
| static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx, |
| grpc_channel_element *elem, |
| grpc_channel_element_args *args) { |
| channel_data *channeld = elem->channel_data; |
| |
| channeld->enabled_algorithms_bitset = |
| grpc_channel_args_compression_algorithm_get_states(args->channel_args); |
| |
| channeld->default_compression_algorithm = |
| grpc_channel_args_get_compression_algorithm(args->channel_args); |
| /* Make sure the default isn't disabled. */ |
| if (!GPR_BITGET(channeld->enabled_algorithms_bitset, |
| channeld->default_compression_algorithm)) { |
| gpr_log(GPR_DEBUG, |
| "compression algorithm %d not enabled: switching to none", |
| channeld->default_compression_algorithm); |
| channeld->default_compression_algorithm = GRPC_COMPRESS_NONE; |
| } |
| |
| channeld->supported_compression_algorithms = 1; /* always support identity */ |
| for (grpc_compression_algorithm algo_idx = 1; |
| algo_idx < GRPC_COMPRESS_ALGORITHMS_COUNT; ++algo_idx) { |
| /* skip disabled algorithms */ |
| if (!GPR_BITGET(channeld->enabled_algorithms_bitset, algo_idx)) { |
| continue; |
| } |
| channeld->supported_compression_algorithms |= 1u << algo_idx; |
| } |
| |
| GPR_ASSERT(!args->is_last); |
| return GRPC_ERROR_NONE; |
| } |
| |
| /* Destructor for channel data */ |
| static void destroy_channel_elem(grpc_exec_ctx *exec_ctx, |
| grpc_channel_element *elem) {} |
| |
| const grpc_channel_filter grpc_message_compress_filter = { |
| compress_start_transport_stream_op_batch, |
| grpc_channel_next_op, |
| sizeof(call_data), |
| init_call_elem, |
| grpc_call_stack_ignore_set_pollset_or_pollset_set, |
| destroy_call_elem, |
| sizeof(channel_data), |
| init_channel_elem, |
| destroy_channel_elem, |
| grpc_call_next_get_peer, |
| grpc_channel_next_get_info, |
| "compress"}; |