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Diffstat (limited to 'src/core/lib/channel/compress_filter.c')
| -rw-r--r-- | src/core/lib/channel/compress_filter.c | 304 |
1 files changed, 304 insertions, 0 deletions
diff --git a/src/core/lib/channel/compress_filter.c b/src/core/lib/channel/compress_filter.c new file mode 100644 index 0000000000..6f5a9740ad --- /dev/null +++ b/src/core/lib/channel/compress_filter.c @@ -0,0 +1,304 @@ +/* + * + * 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 <assert.h> +#include <string.h> + +#include <grpc/compression.h> +#include <grpc/support/alloc.h> +#include <grpc/support/log.h> +#include <grpc/support/slice_buffer.h> + +#include "src/core/channel/channel_args.h" +#include "src/core/channel/compress_filter.h" +#include "src/core/compression/algorithm_metadata.h" +#include "src/core/compression/message_compress.h" +#include "src/core/profiling/timers.h" +#include "src/core/support/string.h" +#include "src/core/transport/static_metadata.h" + +typedef struct call_data { + gpr_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; + /** If true, contents of \a compression_algorithm are authoritative */ + int has_compression_algorithm; + + grpc_transport_stream_op send_op; + uint32_t send_length; + uint32_t send_flags; + gpr_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; + /** Compression options for the channel */ + grpc_compression_options compression_options; + /** Supported compression algorithms */ + uint32_t supported_compression_algorithms; +} channel_data; + +/** For each \a md element from the incoming metadata, filter out the entry for + * "grpc-encoding", using its value to populate the call data's + * compression_algorithm field. */ +static grpc_mdelem *compression_md_filter(void *user_data, grpc_mdelem *md) { + grpc_call_element *elem = user_data; + call_data *calld = elem->call_data; + channel_data *channeld = elem->channel_data; + + if (md->key == GRPC_MDSTR_GRPC_INTERNAL_ENCODING_REQUEST) { + const char *md_c_str = grpc_mdstr_as_c_string(md->value); + if (!grpc_compression_algorithm_parse(md_c_str, strlen(md_c_str), + &calld->compression_algorithm)) { + gpr_log(GPR_ERROR, + "Invalid compression algorithm: '%s' (unknown). Ignoring.", + md_c_str); + calld->compression_algorithm = GRPC_COMPRESS_NONE; + } + if (grpc_compression_options_is_algorithm_enabled( + &channeld->compression_options, calld->compression_algorithm) == + 0) { + gpr_log(GPR_ERROR, + "Invalid compression algorithm: '%s' (previously disabled). " + "Ignoring.", + md_c_str); + calld->compression_algorithm = GRPC_COMPRESS_NONE; + } + calld->has_compression_algorithm = 1; + return NULL; + } + + return md; +} + +static int skip_compression(grpc_call_element *elem) { + call_data *calld = elem->call_data; + channel_data *channeld = elem->channel_data; + if (calld->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 void process_send_initial_metadata( + grpc_call_element *elem, grpc_metadata_batch *initial_metadata) { + call_data *calld = elem->call_data; + channel_data *channeld = elem->channel_data; + /* Parse incoming request for compression. If any, it'll be available + * at calld->compression_algorithm */ + grpc_metadata_batch_filter(initial_metadata, compression_md_filter, elem); + if (!calld->has_compression_algorithm) { + /* 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; + calld->has_compression_algorithm = 1; /* GPR_TRUE */ + } + /* hint compression algorithm */ + grpc_metadata_batch_add_tail( + initial_metadata, &calld->compression_algorithm_storage, + grpc_compression_encoding_mdelem(calld->compression_algorithm)); + + /* convey supported compression algorithms */ + grpc_metadata_batch_add_tail(initial_metadata, + &calld->accept_encoding_storage, + GRPC_MDELEM_ACCEPT_ENCODING_FOR_ALGORITHMS( + channeld->supported_compression_algorithms)); +} + +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, bool success) { + grpc_call_element *elem = elemp; + call_data *calld = elem->call_data; + gpr_slice_buffer_reset_and_unref(&calld->slices); + calld->post_send->cb(exec_ctx, calld->post_send->cb_arg, success); +} + +static void finish_send_message(grpc_exec_ctx *exec_ctx, + grpc_call_element *elem) { + call_data *calld = elem->call_data; + int did_compress; + gpr_slice_buffer tmp; + gpr_slice_buffer_init(&tmp); + did_compress = + grpc_msg_compress(calld->compression_algorithm, &calld->slices, &tmp); + if (did_compress) { + gpr_slice_buffer_swap(&calld->slices, &tmp); + calld->send_flags |= GRPC_WRITE_INTERNAL_COMPRESS; + } + gpr_slice_buffer_destroy(&tmp); + + grpc_slice_buffer_stream_init(&calld->replacement_stream, &calld->slices, + calld->send_flags); + calld->send_op.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, bool success) { + grpc_call_element *elem = elemp; + call_data *calld = elem->call_data; + gpr_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.send_message, + &calld->incoming_slice, ~(size_t)0, + &calld->got_slice)) { + gpr_slice_buffer_add(&calld->slices, calld->incoming_slice); + if (calld->send_length == calld->slices.length) { + finish_send_message(exec_ctx, elem); + break; + } + } +} + +static void compress_start_transport_stream_op(grpc_exec_ctx *exec_ctx, + grpc_call_element *elem, + grpc_transport_stream_op *op) { + call_data *calld = elem->call_data; + + GPR_TIMER_BEGIN("compress_start_transport_stream_op", 0); + + if (op->send_initial_metadata) { + process_send_initial_metadata(elem, op->send_initial_metadata); + } + if (op->send_message != NULL && !skip_compression(elem) && + 0 == (op->send_message->flags & GRPC_WRITE_NO_COMPRESS)) { + calld->send_op = *op; + calld->send_length = op->send_message->length; + calld->send_flags = op->send_message->flags; + continue_send_message(exec_ctx, elem); + } else { + /* pass control down the stack */ + grpc_call_next_op(exec_ctx, elem, op); + } + + GPR_TIMER_END("compress_start_transport_stream_op", 0); +} + +/* Constructor for call_data */ +static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem, + grpc_call_element_args *args) { + /* grab pointers to our data from the call element */ + call_data *calld = elem->call_data; + + /* initialize members */ + gpr_slice_buffer_init(&calld->slices); + calld->has_compression_algorithm = 0; + grpc_closure_init(&calld->got_slice, got_slice, elem); + grpc_closure_init(&calld->send_done, send_done, elem); +} + +/* Destructor for call_data */ +static void destroy_call_elem(grpc_exec_ctx *exec_ctx, + grpc_call_element *elem) { + /* grab pointers to our data from the call element */ + call_data *calld = elem->call_data; + gpr_slice_buffer_destroy(&calld->slices); +} + +/* Constructor for channel_data */ +static void init_channel_elem(grpc_exec_ctx *exec_ctx, + grpc_channel_element *elem, + grpc_channel_element_args *args) { + channel_data *channeld = elem->channel_data; + grpc_compression_algorithm algo_idx; + + grpc_compression_options_init(&channeld->compression_options); + channeld->compression_options.enabled_algorithms_bitset = + (uint32_t)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. */ + GPR_ASSERT(grpc_compression_options_is_algorithm_enabled( + &channeld->compression_options, channeld->default_compression_algorithm)); + channeld->compression_options.default_compression_algorithm = + channeld->default_compression_algorithm; + + channeld->supported_compression_algorithms = 0; + for (algo_idx = 0; algo_idx < GRPC_COMPRESS_ALGORITHMS_COUNT; ++algo_idx) { + /* skip disabled algorithms */ + if (grpc_compression_options_is_algorithm_enabled( + &channeld->compression_options, algo_idx) == 0) { + continue; + } + channeld->supported_compression_algorithms |= 1u << algo_idx; + } + + GPR_ASSERT(!args->is_last); +} + +/* Destructor for channel data */ +static void destroy_channel_elem(grpc_exec_ctx *exec_ctx, + grpc_channel_element *elem) {} + +const grpc_channel_filter grpc_compress_filter = { + compress_start_transport_stream_op, + grpc_channel_next_op, + sizeof(call_data), + init_call_elem, + grpc_call_stack_ignore_set_pollset, + destroy_call_elem, + sizeof(channel_data), + init_channel_elem, + destroy_channel_elem, + grpc_call_next_get_peer, + "compress"}; |