| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "quiche/quic/core/quic_stream_sequencer.h" |
| |
| #include <algorithm> |
| #include <cstddef> |
| #include <limits> |
| #include <string> |
| #include <utility> |
| |
| #include "absl/strings/str_cat.h" |
| #include "absl/strings/string_view.h" |
| #include "quiche/quic/core/quic_clock.h" |
| #include "quiche/quic/core/quic_error_codes.h" |
| #include "quiche/quic/core/quic_packets.h" |
| #include "quiche/quic/core/quic_stream.h" |
| #include "quiche/quic/core/quic_stream_sequencer_buffer.h" |
| #include "quiche/quic/core/quic_types.h" |
| #include "quiche/quic/core/quic_utils.h" |
| #include "quiche/quic/platform/api/quic_bug_tracker.h" |
| #include "quiche/quic/platform/api/quic_flag_utils.h" |
| #include "quiche/quic/platform/api/quic_flags.h" |
| #include "quiche/quic/platform/api/quic_logging.h" |
| #include "quiche/quic/platform/api/quic_stack_trace.h" |
| |
| namespace quic { |
| |
| QuicStreamSequencer::QuicStreamSequencer(StreamInterface* quic_stream) |
| : stream_(quic_stream), |
| buffered_frames_(kStreamReceiveWindowLimit), |
| highest_offset_(0), |
| close_offset_(std::numeric_limits<QuicStreamOffset>::max()), |
| blocked_(false), |
| num_frames_received_(0), |
| num_duplicate_frames_received_(0), |
| ignore_read_data_(false), |
| level_triggered_(false) {} |
| |
| QuicStreamSequencer::~QuicStreamSequencer() { |
| if (stream_ == nullptr) { |
| QUIC_BUG(quic_bug_10858_1) << "Double free'ing QuicStreamSequencer at " |
| << this << ". " << QuicStackTrace(); |
| } |
| stream_ = nullptr; |
| } |
| |
| void QuicStreamSequencer::OnStreamFrame(const QuicStreamFrame& frame) { |
| QUICHE_DCHECK_LE(frame.offset + frame.data_length, close_offset_); |
| ++num_frames_received_; |
| const QuicStreamOffset byte_offset = frame.offset; |
| const size_t data_len = frame.data_length; |
| |
| if (frame.fin && |
| (!CloseStreamAtOffset(frame.offset + data_len) || data_len == 0)) { |
| return; |
| } |
| if (stream_->version().HasIetfQuicFrames() && data_len == 0) { |
| QUICHE_DCHECK(!frame.fin); |
| // Ignore empty frame with no fin. |
| return; |
| } |
| OnFrameData(byte_offset, data_len, frame.data_buffer); |
| } |
| |
| void QuicStreamSequencer::OnCryptoFrame(const QuicCryptoFrame& frame) { |
| ++num_frames_received_; |
| if (frame.data_length == 0) { |
| // Ignore empty crypto frame. |
| return; |
| } |
| OnFrameData(frame.offset, frame.data_length, frame.data_buffer); |
| } |
| |
| void QuicStreamSequencer::OnFrameData(QuicStreamOffset byte_offset, |
| size_t data_len, |
| const char* data_buffer) { |
| highest_offset_ = std::max(highest_offset_, byte_offset + data_len); |
| const size_t previous_readable_bytes = buffered_frames_.ReadableBytes(); |
| size_t bytes_written; |
| std::string error_details; |
| QuicErrorCode result = buffered_frames_.OnStreamData( |
| byte_offset, absl::string_view(data_buffer, data_len), &bytes_written, |
| &error_details); |
| if (result != QUIC_NO_ERROR) { |
| std::string details = |
| absl::StrCat("Stream ", stream_->id(), ": ", |
| QuicErrorCodeToString(result), ": ", error_details); |
| QUIC_LOG_FIRST_N(WARNING, 50) << QuicErrorCodeToString(result); |
| QUIC_LOG_FIRST_N(WARNING, 50) << details; |
| stream_->OnUnrecoverableError(result, details); |
| return; |
| } |
| |
| if (bytes_written == 0) { |
| ++num_duplicate_frames_received_; |
| // Silently ignore duplicates. |
| return; |
| } |
| |
| if (blocked_) { |
| return; |
| } |
| |
| if (level_triggered_) { |
| if (buffered_frames_.ReadableBytes() > previous_readable_bytes) { |
| // Readable bytes has changed, let stream decide if to inform application |
| // or not. |
| if (ignore_read_data_) { |
| FlushBufferedFrames(); |
| } else { |
| stream_->OnDataAvailable(); |
| } |
| } |
| return; |
| } |
| const bool stream_unblocked = |
| previous_readable_bytes == 0 && buffered_frames_.ReadableBytes() > 0; |
| if (stream_unblocked) { |
| if (ignore_read_data_) { |
| FlushBufferedFrames(); |
| } else { |
| stream_->OnDataAvailable(); |
| } |
| } |
| } |
| |
| bool QuicStreamSequencer::CloseStreamAtOffset(QuicStreamOffset offset) { |
| const QuicStreamOffset kMaxOffset = |
| std::numeric_limits<QuicStreamOffset>::max(); |
| |
| // If there is a scheduled close, the new offset should match it. |
| if (close_offset_ != kMaxOffset && offset != close_offset_) { |
| stream_->OnUnrecoverableError( |
| QUIC_STREAM_SEQUENCER_INVALID_STATE, |
| absl::StrCat( |
| "Stream ", stream_->id(), " received new final offset: ", offset, |
| ", which is different from close offset: ", close_offset_)); |
| return false; |
| } |
| |
| // The final offset should be no less than the highest offset that is |
| // received. |
| if (offset < highest_offset_) { |
| stream_->OnUnrecoverableError( |
| QUIC_STREAM_SEQUENCER_INVALID_STATE, |
| absl::StrCat( |
| "Stream ", stream_->id(), " received fin with offset: ", offset, |
| ", which reduces current highest offset: ", highest_offset_)); |
| return false; |
| } |
| |
| close_offset_ = offset; |
| |
| MaybeCloseStream(); |
| return true; |
| } |
| |
| void QuicStreamSequencer::MaybeCloseStream() { |
| if (blocked_ || !IsClosed()) { |
| return; |
| } |
| |
| QUIC_DVLOG(1) << "Passing up termination, as we've processed " |
| << buffered_frames_.BytesConsumed() << " of " << close_offset_ |
| << " bytes."; |
| // This will cause the stream to consume the FIN. |
| // Technically it's an error if |num_bytes_consumed| isn't exactly |
| // equal to |close_offset|, but error handling seems silly at this point. |
| if (ignore_read_data_) { |
| // The sequencer is discarding stream data and must notify the stream on |
| // receipt of a FIN because the consumer won't. |
| stream_->OnFinRead(); |
| } else { |
| stream_->OnDataAvailable(); |
| } |
| buffered_frames_.Clear(); |
| } |
| |
| int QuicStreamSequencer::GetReadableRegions(iovec* iov, size_t iov_len) const { |
| QUICHE_DCHECK(!blocked_); |
| return buffered_frames_.GetReadableRegions(iov, iov_len); |
| } |
| |
| bool QuicStreamSequencer::GetReadableRegion(iovec* iov) const { |
| QUICHE_DCHECK(!blocked_); |
| return buffered_frames_.GetReadableRegion(iov); |
| } |
| |
| bool QuicStreamSequencer::PeekRegion(QuicStreamOffset offset, |
| iovec* iov) const { |
| QUICHE_DCHECK(!blocked_); |
| return buffered_frames_.PeekRegion(offset, iov); |
| } |
| |
| void QuicStreamSequencer::Read(std::string* buffer) { |
| QUICHE_DCHECK(!blocked_); |
| buffer->resize(buffer->size() + ReadableBytes()); |
| iovec iov; |
| iov.iov_len = ReadableBytes(); |
| iov.iov_base = &(*buffer)[buffer->size() - iov.iov_len]; |
| Readv(&iov, 1); |
| } |
| |
| size_t QuicStreamSequencer::Readv(const struct iovec* iov, size_t iov_len) { |
| QUICHE_DCHECK(!blocked_); |
| std::string error_details; |
| size_t bytes_read; |
| QuicErrorCode read_error = |
| buffered_frames_.Readv(iov, iov_len, &bytes_read, &error_details); |
| if (read_error != QUIC_NO_ERROR) { |
| std::string details = |
| absl::StrCat("Stream ", stream_->id(), ": ", error_details); |
| stream_->OnUnrecoverableError(read_error, details); |
| return bytes_read; |
| } |
| |
| stream_->AddBytesConsumed(bytes_read); |
| return bytes_read; |
| } |
| |
| bool QuicStreamSequencer::HasBytesToRead() const { |
| return buffered_frames_.HasBytesToRead(); |
| } |
| |
| size_t QuicStreamSequencer::ReadableBytes() const { |
| return buffered_frames_.ReadableBytes(); |
| } |
| |
| bool QuicStreamSequencer::IsClosed() const { |
| return buffered_frames_.BytesConsumed() >= close_offset_; |
| } |
| |
| void QuicStreamSequencer::MarkConsumed(size_t num_bytes_consumed) { |
| QUICHE_DCHECK(!blocked_); |
| bool result = buffered_frames_.MarkConsumed(num_bytes_consumed); |
| if (!result) { |
| QUIC_BUG(quic_bug_10858_2) |
| << "Invalid argument to MarkConsumed." |
| << " expect to consume: " << num_bytes_consumed |
| << ", but not enough bytes available. " << DebugString(); |
| stream_->ResetWithError( |
| QuicResetStreamError::FromInternal(QUIC_ERROR_PROCESSING_STREAM)); |
| return; |
| } |
| stream_->AddBytesConsumed(num_bytes_consumed); |
| } |
| |
| void QuicStreamSequencer::SetBlockedUntilFlush() { blocked_ = true; } |
| |
| void QuicStreamSequencer::SetUnblocked() { |
| blocked_ = false; |
| if (IsClosed() || HasBytesToRead()) { |
| stream_->OnDataAvailable(); |
| } |
| } |
| |
| void QuicStreamSequencer::StopReading() { |
| if (ignore_read_data_) { |
| return; |
| } |
| ignore_read_data_ = true; |
| FlushBufferedFrames(); |
| } |
| |
| void QuicStreamSequencer::ReleaseBuffer() { |
| buffered_frames_.ReleaseWholeBuffer(); |
| } |
| |
| void QuicStreamSequencer::ReleaseBufferIfEmpty() { |
| if (buffered_frames_.Empty()) { |
| buffered_frames_.ReleaseWholeBuffer(); |
| } |
| } |
| |
| void QuicStreamSequencer::FlushBufferedFrames() { |
| QUICHE_DCHECK(ignore_read_data_); |
| size_t bytes_flushed = buffered_frames_.FlushBufferedFrames(); |
| QUIC_DVLOG(1) << "Flushing buffered data at offset " |
| << buffered_frames_.BytesConsumed() << " length " |
| << bytes_flushed << " for stream " << stream_->id(); |
| stream_->AddBytesConsumed(bytes_flushed); |
| MaybeCloseStream(); |
| } |
| |
| size_t QuicStreamSequencer::NumBytesBuffered() const { |
| return buffered_frames_.BytesBuffered(); |
| } |
| |
| QuicStreamOffset QuicStreamSequencer::NumBytesConsumed() const { |
| return buffered_frames_.BytesConsumed(); |
| } |
| |
| bool QuicStreamSequencer::IsAllDataAvailable() const { |
| QUICHE_DCHECK_LE(NumBytesConsumed() + NumBytesBuffered(), close_offset_); |
| return NumBytesConsumed() + NumBytesBuffered() >= close_offset_; |
| } |
| |
| std::string QuicStreamSequencer::DebugString() const { |
| // clang-format off |
| return absl::StrCat( |
| "QuicStreamSequencer: bytes buffered: ", NumBytesBuffered(), |
| "\n bytes consumed: ", NumBytesConsumed(), |
| "\n first missing byte: ", buffered_frames_.FirstMissingByte(), |
| "\n next expected byte: ", buffered_frames_.NextExpectedByte(), |
| "\n received frames: ", buffered_frames_.ReceivedFramesDebugString(), |
| "\n has bytes to read: ", HasBytesToRead() ? "true" : "false", |
| "\n frames received: ", num_frames_received(), |
| "\n close offset bytes: ", close_offset_, |
| "\n is closed: ", IsClosed() ? "true" : "false"); |
| // clang-format on |
| } |
| |
| } // namespace quic |