|  | // 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 "net/third_party/quiche/src/quic/core/quic_stream.h" | 
|  |  | 
|  | #include <string> | 
|  |  | 
|  | #include "net/third_party/quiche/src/quic/core/quic_error_codes.h" | 
|  | #include "net/third_party/quiche/src/quic/core/quic_flow_controller.h" | 
|  | #include "net/third_party/quiche/src/quic/core/quic_session.h" | 
|  | #include "net/third_party/quiche/src/quic/core/quic_types.h" | 
|  | #include "net/third_party/quiche/src/quic/core/quic_utils.h" | 
|  | #include "net/third_party/quiche/src/quic/platform/api/quic_bug_tracker.h" | 
|  | #include "net/third_party/quiche/src/quic/platform/api/quic_flag_utils.h" | 
|  | #include "net/third_party/quiche/src/quic/platform/api/quic_flags.h" | 
|  | #include "net/third_party/quiche/src/quic/platform/api/quic_logging.h" | 
|  | #include "net/third_party/quiche/src/quic/platform/api/quic_str_cat.h" | 
|  |  | 
|  | using spdy::SpdyPriority; | 
|  |  | 
|  | namespace quic { | 
|  |  | 
|  | #define ENDPOINT \ | 
|  | (session_->perspective() == Perspective::IS_SERVER ? "Server: " : "Client: ") | 
|  |  | 
|  | namespace { | 
|  |  | 
|  | size_t DefaultFlowControlWindow(ParsedQuicVersion version) { | 
|  | if (!version.AllowsLowFlowControlLimits()) { | 
|  | return kDefaultFlowControlSendWindow; | 
|  | } | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | size_t GetInitialStreamFlowControlWindowToSend(QuicSession* session, | 
|  | QuicStreamId stream_id) { | 
|  | ParsedQuicVersion version = session->connection()->version(); | 
|  | if (version.handshake_protocol != PROTOCOL_TLS1_3) { | 
|  | return session->config()->GetInitialStreamFlowControlWindowToSend(); | 
|  | } | 
|  |  | 
|  | // Unidirectional streams (v99 only). | 
|  | if (VersionHasIetfQuicFrames(version.transport_version) && | 
|  | !QuicUtils::IsBidirectionalStreamId(stream_id)) { | 
|  | return session->config() | 
|  | ->GetInitialMaxStreamDataBytesUnidirectionalToSend(); | 
|  | } | 
|  |  | 
|  | if (QuicUtils::IsOutgoingStreamId(version, stream_id, | 
|  | session->perspective())) { | 
|  | return session->config() | 
|  | ->GetInitialMaxStreamDataBytesOutgoingBidirectionalToSend(); | 
|  | } | 
|  |  | 
|  | return session->config() | 
|  | ->GetInitialMaxStreamDataBytesIncomingBidirectionalToSend(); | 
|  | } | 
|  |  | 
|  | size_t GetReceivedFlowControlWindow(QuicSession* session, | 
|  | QuicStreamId stream_id) { | 
|  | ParsedQuicVersion version = session->connection()->version(); | 
|  | if (version.handshake_protocol != PROTOCOL_TLS1_3) { | 
|  | if (session->config()->HasReceivedInitialStreamFlowControlWindowBytes()) { | 
|  | return session->config()->ReceivedInitialStreamFlowControlWindowBytes(); | 
|  | } | 
|  |  | 
|  | return DefaultFlowControlWindow(version); | 
|  | } | 
|  |  | 
|  | // Unidirectional streams (v99 only). | 
|  | if (VersionHasIetfQuicFrames(version.transport_version) && | 
|  | !QuicUtils::IsBidirectionalStreamId(stream_id)) { | 
|  | if (session->config() | 
|  | ->HasReceivedInitialMaxStreamDataBytesUnidirectional()) { | 
|  | return session->config() | 
|  | ->ReceivedInitialMaxStreamDataBytesUnidirectional(); | 
|  | } | 
|  |  | 
|  | return DefaultFlowControlWindow(version); | 
|  | } | 
|  |  | 
|  | if (QuicUtils::IsOutgoingStreamId(version, stream_id, | 
|  | session->perspective())) { | 
|  | if (session->config() | 
|  | ->HasReceivedInitialMaxStreamDataBytesOutgoingBidirectional()) { | 
|  | return session->config() | 
|  | ->ReceivedInitialMaxStreamDataBytesOutgoingBidirectional(); | 
|  | } | 
|  |  | 
|  | return DefaultFlowControlWindow(version); | 
|  | } | 
|  |  | 
|  | if (session->config() | 
|  | ->HasReceivedInitialMaxStreamDataBytesIncomingBidirectional()) { | 
|  | return session->config() | 
|  | ->ReceivedInitialMaxStreamDataBytesIncomingBidirectional(); | 
|  | } | 
|  |  | 
|  | return DefaultFlowControlWindow(version); | 
|  | } | 
|  |  | 
|  | }  // namespace | 
|  |  | 
|  | // static | 
|  | const SpdyPriority QuicStream::kDefaultPriority; | 
|  |  | 
|  | PendingStream::PendingStream(QuicStreamId id, QuicSession* session) | 
|  | : id_(id), | 
|  | session_(session), | 
|  | stream_bytes_read_(0), | 
|  | fin_received_(false), | 
|  | connection_flow_controller_(session->flow_controller()), | 
|  | flow_controller_(session, | 
|  | id, | 
|  | /*is_connection_flow_controller*/ false, | 
|  | GetReceivedFlowControlWindow(session, id), | 
|  | GetInitialStreamFlowControlWindowToSend(session, id), | 
|  | kStreamReceiveWindowLimit, | 
|  | session_->flow_controller()->auto_tune_receive_window(), | 
|  | session_->flow_controller()), | 
|  | sequencer_(this) {} | 
|  |  | 
|  | void PendingStream::OnDataAvailable() { | 
|  | // Data should be kept in the sequencer so that | 
|  | // QuicSession::ProcessPendingStream() can read it. | 
|  | } | 
|  |  | 
|  | void PendingStream::OnFinRead() { | 
|  | DCHECK(sequencer_.IsClosed()); | 
|  | } | 
|  |  | 
|  | void PendingStream::AddBytesConsumed(QuicByteCount bytes) { | 
|  | // It will be called when the metadata of the stream is consumed. | 
|  | flow_controller_.AddBytesConsumed(bytes); | 
|  | connection_flow_controller_->AddBytesConsumed(bytes); | 
|  | } | 
|  |  | 
|  | void PendingStream::Reset(QuicRstStreamErrorCode /*error*/) { | 
|  | // Currently PendingStream is only read-unidirectional. It shouldn't send | 
|  | // Reset. | 
|  | DCHECK_EQ(READ_UNIDIRECTIONAL, | 
|  | QuicUtils::GetStreamType(id_, session_->perspective(), | 
|  | /*peer_initiated = */ true)); | 
|  | QUIC_NOTREACHED(); | 
|  | } | 
|  |  | 
|  | void PendingStream::CloseConnectionWithDetails(QuicErrorCode error, | 
|  | const std::string& details) { | 
|  | session_->connection()->CloseConnection( | 
|  | error, details, ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET); | 
|  | } | 
|  |  | 
|  | QuicStreamId PendingStream::id() const { | 
|  | return id_; | 
|  | } | 
|  |  | 
|  | const QuicSocketAddress& PendingStream::PeerAddressOfLatestPacket() const { | 
|  | return session_->connection()->last_packet_source_address(); | 
|  | } | 
|  |  | 
|  | void PendingStream::OnStreamFrame(const QuicStreamFrame& frame) { | 
|  | DCHECK_EQ(frame.stream_id, id_); | 
|  |  | 
|  | bool is_stream_too_long = | 
|  | (frame.offset > kMaxStreamLength) || | 
|  | (kMaxStreamLength - frame.offset < frame.data_length); | 
|  | if (is_stream_too_long) { | 
|  | // Close connection if stream becomes too long. | 
|  | QUIC_PEER_BUG | 
|  | << "Receive stream frame reaches max stream length. frame offset " | 
|  | << frame.offset << " length " << frame.data_length; | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_LENGTH_OVERFLOW, | 
|  | "Peer sends more data than allowed on this stream."); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (frame.offset + frame.data_length > sequencer_.close_offset()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_DATA_BEYOND_CLOSE_OFFSET, | 
|  | QuicStrCat( | 
|  | "Stream ", id_, | 
|  | " received data with offset: ", frame.offset + frame.data_length, | 
|  | ", which is beyond close offset: ", sequencer()->close_offset())); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (frame.fin) { | 
|  | fin_received_ = true; | 
|  | } | 
|  |  | 
|  | // This count includes duplicate data received. | 
|  | size_t frame_payload_size = frame.data_length; | 
|  | stream_bytes_read_ += frame_payload_size; | 
|  |  | 
|  | // Flow control is interested in tracking highest received offset. | 
|  | // Only interested in received frames that carry data. | 
|  | if (frame_payload_size > 0 && | 
|  | MaybeIncreaseHighestReceivedOffset(frame.offset + frame_payload_size)) { | 
|  | // As the highest received offset has changed, check to see if this is a | 
|  | // violation of flow control. | 
|  | if (flow_controller_.FlowControlViolation() || | 
|  | connection_flow_controller_->FlowControlViolation()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA, | 
|  | "Flow control violation after increasing offset"); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | sequencer_.OnStreamFrame(frame); | 
|  | } | 
|  |  | 
|  | void PendingStream::OnRstStreamFrame(const QuicRstStreamFrame& frame) { | 
|  | DCHECK_EQ(frame.stream_id, id_); | 
|  |  | 
|  | if (frame.byte_offset > kMaxStreamLength) { | 
|  | // Peer are not suppose to write bytes more than maxium allowed. | 
|  | CloseConnectionWithDetails(QUIC_STREAM_LENGTH_OVERFLOW, | 
|  | "Reset frame stream offset overflow."); | 
|  | return; | 
|  | } | 
|  |  | 
|  | const QuicStreamOffset kMaxOffset = | 
|  | std::numeric_limits<QuicStreamOffset>::max(); | 
|  | if (sequencer()->close_offset() != kMaxOffset && | 
|  | frame.byte_offset != sequencer()->close_offset()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_MULTIPLE_OFFSET, | 
|  | QuicStrCat("Stream ", id_, | 
|  | " received new final offset: ", frame.byte_offset, | 
|  | ", which is different from close offset: ", | 
|  | sequencer()->close_offset())); | 
|  | return; | 
|  | } | 
|  |  | 
|  | MaybeIncreaseHighestReceivedOffset(frame.byte_offset); | 
|  | if (flow_controller_.FlowControlViolation() || | 
|  | connection_flow_controller_->FlowControlViolation()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA, | 
|  | "Flow control violation after increasing offset"); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | bool PendingStream::MaybeIncreaseHighestReceivedOffset( | 
|  | QuicStreamOffset new_offset) { | 
|  | uint64_t increment = | 
|  | new_offset - flow_controller_.highest_received_byte_offset(); | 
|  | if (!flow_controller_.UpdateHighestReceivedOffset(new_offset)) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | // If |new_offset| increased the stream flow controller's highest received | 
|  | // offset, increase the connection flow controller's value by the incremental | 
|  | // difference. | 
|  | connection_flow_controller_->UpdateHighestReceivedOffset( | 
|  | connection_flow_controller_->highest_received_byte_offset() + increment); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | void PendingStream::MarkConsumed(size_t num_bytes) { | 
|  | sequencer_.MarkConsumed(num_bytes); | 
|  | } | 
|  |  | 
|  | void PendingStream::StopReading() { | 
|  | QUIC_DVLOG(1) << "Stop reading from pending stream " << id(); | 
|  | sequencer_.StopReading(); | 
|  | } | 
|  |  | 
|  | QuicStream::QuicStream(PendingStream* pending, StreamType type, bool is_static) | 
|  | : QuicStream(pending->id_, | 
|  | pending->session_, | 
|  | std::move(pending->sequencer_), | 
|  | is_static, | 
|  | type, | 
|  | pending->stream_bytes_read_, | 
|  | pending->fin_received_, | 
|  | std::move(pending->flow_controller_), | 
|  | pending->connection_flow_controller_) { | 
|  | sequencer_.set_stream(this); | 
|  | } | 
|  |  | 
|  | namespace { | 
|  |  | 
|  | QuicOptional<QuicFlowController> FlowController(QuicStreamId id, | 
|  | QuicSession* session, | 
|  | StreamType type) { | 
|  | if (type == CRYPTO) { | 
|  | // The only QuicStream with a StreamType of CRYPTO is QuicCryptoStream, when | 
|  | // it is using crypto frames instead of stream frames. The QuicCryptoStream | 
|  | // doesn't have any flow control in that case, so we don't create a | 
|  | // QuicFlowController for it. | 
|  | return QuicOptional<QuicFlowController>(); | 
|  | } | 
|  | return QuicFlowController( | 
|  | session, id, | 
|  | /*is_connection_flow_controller*/ false, | 
|  | GetReceivedFlowControlWindow(session, id), | 
|  | GetInitialStreamFlowControlWindowToSend(session, id), | 
|  | kStreamReceiveWindowLimit, | 
|  | session->flow_controller()->auto_tune_receive_window(), | 
|  | session->flow_controller()); | 
|  | } | 
|  |  | 
|  | }  // namespace | 
|  |  | 
|  | QuicStream::QuicStream(QuicStreamId id, | 
|  | QuicSession* session, | 
|  | bool is_static, | 
|  | StreamType type) | 
|  | : QuicStream(id, | 
|  | session, | 
|  | QuicStreamSequencer(this), | 
|  | is_static, | 
|  | type, | 
|  | 0, | 
|  | false, | 
|  | FlowController(id, session, type), | 
|  | session->flow_controller()) {} | 
|  |  | 
|  | QuicStream::QuicStream(QuicStreamId id, | 
|  | QuicSession* session, | 
|  | QuicStreamSequencer sequencer, | 
|  | bool is_static, | 
|  | StreamType type, | 
|  | uint64_t stream_bytes_read, | 
|  | bool fin_received, | 
|  | QuicOptional<QuicFlowController> flow_controller, | 
|  | QuicFlowController* connection_flow_controller) | 
|  | : sequencer_(std::move(sequencer)), | 
|  | id_(id), | 
|  | session_(session), | 
|  | precedence_( | 
|  | session->use_http2_priority_write_scheduler() | 
|  | ? spdy::SpdyStreamPrecedence(0, | 
|  | spdy::kHttp2DefaultStreamWeight, | 
|  | false) | 
|  | : spdy::SpdyStreamPrecedence(kDefaultPriority)), | 
|  | stream_bytes_read_(stream_bytes_read), | 
|  | stream_error_(QUIC_STREAM_NO_ERROR), | 
|  | connection_error_(QUIC_NO_ERROR), | 
|  | read_side_closed_(false), | 
|  | write_side_closed_(false), | 
|  | fin_buffered_(false), | 
|  | fin_sent_(false), | 
|  | fin_outstanding_(false), | 
|  | fin_lost_(false), | 
|  | fin_received_(fin_received), | 
|  | rst_sent_(false), | 
|  | rst_received_(false), | 
|  | flow_controller_(std::move(flow_controller)), | 
|  | connection_flow_controller_(connection_flow_controller), | 
|  | stream_contributes_to_connection_flow_control_(true), | 
|  | busy_counter_(0), | 
|  | add_random_padding_after_fin_(false), | 
|  | send_buffer_( | 
|  | session->connection()->helper()->GetStreamSendBufferAllocator()), | 
|  | buffered_data_threshold_(GetQuicFlag(FLAGS_quic_buffered_data_threshold)), | 
|  | is_static_(is_static), | 
|  | deadline_(QuicTime::Zero()), | 
|  | type_(VersionHasIetfQuicFrames(session->transport_version()) && | 
|  | type != CRYPTO | 
|  | ? QuicUtils::GetStreamType(id_, | 
|  | session->perspective(), | 
|  | session->IsIncomingStream(id_)) | 
|  | : type) { | 
|  | if (type_ == WRITE_UNIDIRECTIONAL) { | 
|  | set_fin_received(true); | 
|  | CloseReadSide(); | 
|  | } else if (type_ == READ_UNIDIRECTIONAL) { | 
|  | set_fin_sent(true); | 
|  | CloseWriteSide(); | 
|  | } | 
|  | if (type_ != CRYPTO) { | 
|  | session_->RegisterStreamPriority(id, is_static_, precedence_); | 
|  | } | 
|  | } | 
|  |  | 
|  | QuicStream::~QuicStream() { | 
|  | if (session_ != nullptr && IsWaitingForAcks()) { | 
|  | QUIC_DVLOG(1) | 
|  | << ENDPOINT << "Stream " << id_ | 
|  | << " gets destroyed while waiting for acks. stream_bytes_outstanding = " | 
|  | << send_buffer_.stream_bytes_outstanding() | 
|  | << ", fin_outstanding: " << fin_outstanding_; | 
|  | } | 
|  | if (session_ != nullptr && type_ != CRYPTO) { | 
|  | session_->UnregisterStreamPriority(id(), is_static_); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::OnStreamFrame(const QuicStreamFrame& frame) { | 
|  | DCHECK_EQ(frame.stream_id, id_); | 
|  |  | 
|  | DCHECK(!(read_side_closed_ && write_side_closed_)); | 
|  |  | 
|  | if (type_ == WRITE_UNIDIRECTIONAL) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_DATA_RECEIVED_ON_WRITE_UNIDIRECTIONAL_STREAM, | 
|  | "Data received on write unidirectional stream"); | 
|  | return; | 
|  | } | 
|  |  | 
|  | bool is_stream_too_long = | 
|  | (frame.offset > kMaxStreamLength) || | 
|  | (kMaxStreamLength - frame.offset < frame.data_length); | 
|  | if (is_stream_too_long) { | 
|  | // Close connection if stream becomes too long. | 
|  | QUIC_PEER_BUG << "Receive stream frame on stream " << id_ | 
|  | << " reaches max stream length. frame offset " << frame.offset | 
|  | << " length " << frame.data_length << ". " | 
|  | << sequencer_.DebugString(); | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_LENGTH_OVERFLOW, | 
|  | QuicStrCat("Peer sends more data than allowed on stream ", id_, | 
|  | ". frame: offset = ", frame.offset, ", length = ", | 
|  | frame.data_length, ". ", sequencer_.DebugString())); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (frame.offset + frame.data_length > sequencer_.close_offset()) { | 
|  | if (!GetQuicReloadableFlag(quic_close_connection_on_wrong_offset)) { | 
|  | Reset(QUIC_DATA_AFTER_CLOSE_OFFSET); | 
|  | return; | 
|  | } | 
|  | QUIC_RELOADABLE_FLAG_COUNT_N(quic_close_connection_on_wrong_offset, 1, 2); | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_DATA_BEYOND_CLOSE_OFFSET, | 
|  | QuicStrCat( | 
|  | "Stream ", id_, | 
|  | " received data with offset: ", frame.offset + frame.data_length, | 
|  | ", which is beyond close offset: ", sequencer_.close_offset())); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (frame.fin) { | 
|  | fin_received_ = true; | 
|  | if (fin_sent_) { | 
|  | session_->StreamDraining(id_); | 
|  | } | 
|  | } | 
|  |  | 
|  | if (read_side_closed_) { | 
|  | QUIC_DLOG(INFO) | 
|  | << ENDPOINT << "Stream " << frame.stream_id | 
|  | << " is closed for reading. Ignoring newly received stream data."; | 
|  | // The subclass does not want to read data:  blackhole the data. | 
|  | return; | 
|  | } | 
|  |  | 
|  | // This count includes duplicate data received. | 
|  | size_t frame_payload_size = frame.data_length; | 
|  | stream_bytes_read_ += frame_payload_size; | 
|  |  | 
|  | // Flow control is interested in tracking highest received offset. | 
|  | // Only interested in received frames that carry data. | 
|  | if (frame_payload_size > 0 && | 
|  | MaybeIncreaseHighestReceivedOffset(frame.offset + frame_payload_size)) { | 
|  | // As the highest received offset has changed, check to see if this is a | 
|  | // violation of flow control. | 
|  | if (flow_controller_->FlowControlViolation() || | 
|  | connection_flow_controller_->FlowControlViolation()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA, | 
|  | "Flow control violation after increasing offset"); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | sequencer_.OnStreamFrame(frame); | 
|  | } | 
|  |  | 
|  | int QuicStream::num_frames_received() const { | 
|  | return sequencer_.num_frames_received(); | 
|  | } | 
|  |  | 
|  | int QuicStream::num_duplicate_frames_received() const { | 
|  | return sequencer_.num_duplicate_frames_received(); | 
|  | } | 
|  |  | 
|  | void QuicStream::OnStreamReset(const QuicRstStreamFrame& frame) { | 
|  | rst_received_ = true; | 
|  | if (frame.byte_offset > kMaxStreamLength) { | 
|  | // Peer are not suppose to write bytes more than maxium allowed. | 
|  | CloseConnectionWithDetails(QUIC_STREAM_LENGTH_OVERFLOW, | 
|  | "Reset frame stream offset overflow."); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (GetQuicReloadableFlag(quic_close_connection_on_wrong_offset)) { | 
|  | QUIC_RELOADABLE_FLAG_COUNT_N(quic_close_connection_on_wrong_offset, 2, 2); | 
|  | const QuicStreamOffset kMaxOffset = | 
|  | std::numeric_limits<QuicStreamOffset>::max(); | 
|  | if (sequencer()->close_offset() != kMaxOffset && | 
|  | frame.byte_offset != sequencer()->close_offset()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_MULTIPLE_OFFSET, | 
|  | QuicStrCat("Stream ", id_, | 
|  | " received new final offset: ", frame.byte_offset, | 
|  | ", which is different from close offset: ", | 
|  | sequencer_.close_offset())); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | MaybeIncreaseHighestReceivedOffset(frame.byte_offset); | 
|  | if (flow_controller_->FlowControlViolation() || | 
|  | connection_flow_controller_->FlowControlViolation()) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA, | 
|  | "Flow control violation after increasing offset"); | 
|  | return; | 
|  | } | 
|  |  | 
|  | stream_error_ = frame.error_code; | 
|  | // Google QUIC closes both sides of the stream in response to a | 
|  | // RESET_STREAM, IETF QUIC closes only the read side. | 
|  | if (!VersionHasIetfQuicFrames(transport_version())) { | 
|  | CloseWriteSide(); | 
|  | } | 
|  | CloseReadSide(); | 
|  | } | 
|  |  | 
|  | void QuicStream::OnConnectionClosed(QuicErrorCode error, | 
|  | ConnectionCloseSource /*source*/) { | 
|  | if (read_side_closed_ && write_side_closed_) { | 
|  | return; | 
|  | } | 
|  | if (error != QUIC_NO_ERROR) { | 
|  | stream_error_ = QUIC_STREAM_CONNECTION_ERROR; | 
|  | connection_error_ = error; | 
|  | } | 
|  |  | 
|  | CloseWriteSide(); | 
|  | CloseReadSide(); | 
|  | } | 
|  |  | 
|  | void QuicStream::OnFinRead() { | 
|  | DCHECK(sequencer_.IsClosed()); | 
|  | // OnFinRead can be called due to a FIN flag in a headers block, so there may | 
|  | // have been no OnStreamFrame call with a FIN in the frame. | 
|  | fin_received_ = true; | 
|  | // If fin_sent_ is true, then CloseWriteSide has already been called, and the | 
|  | // stream will be destroyed by CloseReadSide, so don't need to call | 
|  | // StreamDraining. | 
|  | CloseReadSide(); | 
|  | } | 
|  |  | 
|  | void QuicStream::Reset(QuicRstStreamErrorCode error) { | 
|  | stream_error_ = error; | 
|  | // Sending a RstStream results in calling CloseStream. | 
|  | session()->SendRstStream(id(), error, stream_bytes_written()); | 
|  | rst_sent_ = true; | 
|  | } | 
|  |  | 
|  | void QuicStream::CloseConnectionWithDetails(QuicErrorCode error, | 
|  | const std::string& details) { | 
|  | session()->connection()->CloseConnection( | 
|  | error, details, ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET); | 
|  | } | 
|  |  | 
|  | const spdy::SpdyStreamPrecedence& QuicStream::precedence() const { | 
|  | return precedence_; | 
|  | } | 
|  |  | 
|  | void QuicStream::SetPriority(const spdy::SpdyStreamPrecedence& precedence) { | 
|  | precedence_ = precedence; | 
|  | session_->UpdateStreamPriority(id(), precedence); | 
|  | } | 
|  |  | 
|  | void QuicStream::WriteOrBufferData( | 
|  | QuicStringPiece data, | 
|  | bool fin, | 
|  | QuicReferenceCountedPointer<QuicAckListenerInterface> ack_listener) { | 
|  | if (data.empty() && !fin) { | 
|  | QUIC_BUG << "data.empty() && !fin"; | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (fin_buffered_) { | 
|  | QUIC_BUG << "Fin already buffered"; | 
|  | return; | 
|  | } | 
|  | if (write_side_closed_) { | 
|  | QUIC_DLOG(ERROR) << ENDPOINT | 
|  | << "Attempt to write when the write side is closed"; | 
|  | if (type_ == READ_UNIDIRECTIONAL) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_TRY_TO_WRITE_DATA_ON_READ_UNIDIRECTIONAL_STREAM, | 
|  | "Try to send data on read unidirectional stream"); | 
|  | } | 
|  | return; | 
|  | } | 
|  |  | 
|  | fin_buffered_ = fin; | 
|  |  | 
|  | bool had_buffered_data = HasBufferedData(); | 
|  | // Do not respect buffered data upper limit as WriteOrBufferData guarantees | 
|  | // all data to be consumed. | 
|  | if (data.length() > 0) { | 
|  | struct iovec iov(QuicUtils::MakeIovec(data)); | 
|  | QuicStreamOffset offset = send_buffer_.stream_offset(); | 
|  | if (kMaxStreamLength - offset < data.length()) { | 
|  | QUIC_BUG << "Write too many data via stream " << id_; | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_LENGTH_OVERFLOW, | 
|  | QuicStrCat("Write too many data via stream ", id_)); | 
|  | return; | 
|  | } | 
|  | send_buffer_.SaveStreamData(&iov, 1, 0, data.length()); | 
|  | OnDataBuffered(offset, data.length(), ack_listener); | 
|  | } | 
|  | if (!had_buffered_data && (HasBufferedData() || fin_buffered_)) { | 
|  | // Write data if there is no buffered data before. | 
|  | WriteBufferedData(); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::OnCanWrite() { | 
|  | if (HasDeadlinePassed()) { | 
|  | OnDeadlinePassed(); | 
|  | return; | 
|  | } | 
|  | if (HasPendingRetransmission()) { | 
|  | WritePendingRetransmission(); | 
|  | // Exit early to allow other streams to write pending retransmissions if | 
|  | // any. | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (write_side_closed_) { | 
|  | QUIC_DLOG(ERROR) | 
|  | << ENDPOINT << "Stream " << id() | 
|  | << " attempting to write new data when the write side is closed"; | 
|  | return; | 
|  | } | 
|  | if (HasBufferedData() || (fin_buffered_ && !fin_sent_)) { | 
|  | WriteBufferedData(); | 
|  | } | 
|  | if (!fin_buffered_ && !fin_sent_ && CanWriteNewData()) { | 
|  | // Notify upper layer to write new data when buffered data size is below | 
|  | // low water mark. | 
|  | OnCanWriteNewData(); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::MaybeSendBlocked() { | 
|  | if (flow_controller_->ShouldSendBlocked()) { | 
|  | session_->SendBlocked(id_); | 
|  | } | 
|  | if (!stream_contributes_to_connection_flow_control_) { | 
|  | return; | 
|  | } | 
|  | if (connection_flow_controller_->ShouldSendBlocked()) { | 
|  | session_->SendBlocked(QuicUtils::GetInvalidStreamId(transport_version())); | 
|  | } | 
|  | // If the stream is blocked by connection-level flow control but not by | 
|  | // stream-level flow control, add the stream to the write blocked list so that | 
|  | // the stream will be given a chance to write when a connection-level | 
|  | // WINDOW_UPDATE arrives. | 
|  | if (connection_flow_controller_->IsBlocked() && | 
|  | !flow_controller_->IsBlocked()) { | 
|  | session_->MarkConnectionLevelWriteBlocked(id()); | 
|  | } | 
|  | } | 
|  |  | 
|  | QuicConsumedData QuicStream::WriteMemSlices(QuicMemSliceSpan span, bool fin) { | 
|  | QuicConsumedData consumed_data(0, false); | 
|  | if (span.empty() && !fin) { | 
|  | QUIC_BUG << "span.empty() && !fin"; | 
|  | return consumed_data; | 
|  | } | 
|  |  | 
|  | if (fin_buffered_) { | 
|  | QUIC_BUG << "Fin already buffered"; | 
|  | return consumed_data; | 
|  | } | 
|  |  | 
|  | if (write_side_closed_) { | 
|  | QUIC_DLOG(ERROR) << ENDPOINT << "Stream " << id() | 
|  | << " attempting to write when the write side is closed"; | 
|  | if (type_ == READ_UNIDIRECTIONAL) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_TRY_TO_WRITE_DATA_ON_READ_UNIDIRECTIONAL_STREAM, | 
|  | "Try to send data on read unidirectional stream"); | 
|  | } | 
|  | return consumed_data; | 
|  | } | 
|  |  | 
|  | bool had_buffered_data = HasBufferedData(); | 
|  | if (CanWriteNewData() || span.empty()) { | 
|  | consumed_data.fin_consumed = fin; | 
|  | if (!span.empty()) { | 
|  | // Buffer all data if buffered data size is below limit. | 
|  | QuicStreamOffset offset = send_buffer_.stream_offset(); | 
|  | consumed_data.bytes_consumed = send_buffer_.SaveMemSliceSpan(span); | 
|  | if (offset > send_buffer_.stream_offset() || | 
|  | kMaxStreamLength < send_buffer_.stream_offset()) { | 
|  | QUIC_BUG << "Write too many data via stream " << id_; | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_STREAM_LENGTH_OVERFLOW, | 
|  | QuicStrCat("Write too many data via stream ", id_)); | 
|  | return consumed_data; | 
|  | } | 
|  | OnDataBuffered(offset, consumed_data.bytes_consumed, nullptr); | 
|  | } | 
|  | } | 
|  | fin_buffered_ = consumed_data.fin_consumed; | 
|  |  | 
|  | if (!had_buffered_data && (HasBufferedData() || fin_buffered_)) { | 
|  | // Write data if there is no buffered data before. | 
|  | WriteBufferedData(); | 
|  | } | 
|  |  | 
|  | return consumed_data; | 
|  | } | 
|  |  | 
|  | bool QuicStream::HasPendingRetransmission() const { | 
|  | return send_buffer_.HasPendingRetransmission() || fin_lost_; | 
|  | } | 
|  |  | 
|  | bool QuicStream::IsStreamFrameOutstanding(QuicStreamOffset offset, | 
|  | QuicByteCount data_length, | 
|  | bool fin) const { | 
|  | return send_buffer_.IsStreamDataOutstanding(offset, data_length) || | 
|  | (fin && fin_outstanding_); | 
|  | } | 
|  |  | 
|  | void QuicStream::CloseReadSide() { | 
|  | if (read_side_closed_) { | 
|  | return; | 
|  | } | 
|  | QUIC_DVLOG(1) << ENDPOINT << "Done reading from stream " << id(); | 
|  |  | 
|  | read_side_closed_ = true; | 
|  | sequencer_.ReleaseBuffer(); | 
|  |  | 
|  | if (write_side_closed_) { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "Closing stream " << id(); | 
|  | session_->CloseStream(id()); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::CloseWriteSide() { | 
|  | if (write_side_closed_) { | 
|  | return; | 
|  | } | 
|  | QUIC_DVLOG(1) << ENDPOINT << "Done writing to stream " << id(); | 
|  |  | 
|  | write_side_closed_ = true; | 
|  | if (read_side_closed_) { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "Closing stream " << id(); | 
|  | session_->CloseStream(id()); | 
|  | } | 
|  | } | 
|  |  | 
|  | bool QuicStream::HasBufferedData() const { | 
|  | DCHECK_GE(send_buffer_.stream_offset(), stream_bytes_written()); | 
|  | return send_buffer_.stream_offset() > stream_bytes_written(); | 
|  | } | 
|  |  | 
|  | QuicTransportVersion QuicStream::transport_version() const { | 
|  | return session_->transport_version(); | 
|  | } | 
|  |  | 
|  | HandshakeProtocol QuicStream::handshake_protocol() const { | 
|  | return session_->connection()->version().handshake_protocol; | 
|  | } | 
|  |  | 
|  | void QuicStream::StopReading() { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "Stop reading from stream " << id(); | 
|  | sequencer_.StopReading(); | 
|  | } | 
|  |  | 
|  | const QuicSocketAddress& QuicStream::PeerAddressOfLatestPacket() const { | 
|  | return session_->connection()->last_packet_source_address(); | 
|  | } | 
|  |  | 
|  | void QuicStream::OnClose() { | 
|  | CloseReadSide(); | 
|  | CloseWriteSide(); | 
|  |  | 
|  | if (!fin_sent_ && !rst_sent_) { | 
|  | // For flow control accounting, tell the peer how many bytes have been | 
|  | // written on this stream before termination. Done here if needed, using a | 
|  | // RST_STREAM frame. | 
|  | QUIC_DLOG(INFO) << ENDPOINT << "Sending RST_STREAM in OnClose: " << id(); | 
|  | session_->SendRstStream(id(), QUIC_RST_ACKNOWLEDGEMENT, | 
|  | stream_bytes_written()); | 
|  | session_->OnStreamDoneWaitingForAcks(id_); | 
|  | rst_sent_ = true; | 
|  | } | 
|  |  | 
|  | if (flow_controller_->FlowControlViolation() || | 
|  | connection_flow_controller_->FlowControlViolation()) { | 
|  | return; | 
|  | } | 
|  | // The stream is being closed and will not process any further incoming bytes. | 
|  | // As there may be more bytes in flight, to ensure that both endpoints have | 
|  | // the same connection level flow control state, mark all unreceived or | 
|  | // buffered bytes as consumed. | 
|  | QuicByteCount bytes_to_consume = | 
|  | flow_controller_->highest_received_byte_offset() - | 
|  | flow_controller_->bytes_consumed(); | 
|  | AddBytesConsumed(bytes_to_consume); | 
|  | } | 
|  |  | 
|  | void QuicStream::OnWindowUpdateFrame(const QuicWindowUpdateFrame& frame) { | 
|  | if (type_ == READ_UNIDIRECTIONAL) { | 
|  | CloseConnectionWithDetails( | 
|  | QUIC_WINDOW_UPDATE_RECEIVED_ON_READ_UNIDIRECTIONAL_STREAM, | 
|  | "WindowUpdateFrame received on READ_UNIDIRECTIONAL stream."); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (flow_controller_->UpdateSendWindowOffset(frame.byte_offset)) { | 
|  | // Let session unblock this stream. | 
|  | session_->MarkConnectionLevelWriteBlocked(id_); | 
|  | } | 
|  | } | 
|  |  | 
|  | bool QuicStream::MaybeIncreaseHighestReceivedOffset( | 
|  | QuicStreamOffset new_offset) { | 
|  | uint64_t increment = | 
|  | new_offset - flow_controller_->highest_received_byte_offset(); | 
|  | if (!flow_controller_->UpdateHighestReceivedOffset(new_offset)) { | 
|  | return false; | 
|  | } | 
|  |  | 
|  | // If |new_offset| increased the stream flow controller's highest received | 
|  | // offset, increase the connection flow controller's value by the incremental | 
|  | // difference. | 
|  | if (stream_contributes_to_connection_flow_control_) { | 
|  | connection_flow_controller_->UpdateHighestReceivedOffset( | 
|  | connection_flow_controller_->highest_received_byte_offset() + | 
|  | increment); | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | void QuicStream::AddBytesSent(QuicByteCount bytes) { | 
|  | flow_controller_->AddBytesSent(bytes); | 
|  | if (stream_contributes_to_connection_flow_control_) { | 
|  | connection_flow_controller_->AddBytesSent(bytes); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::AddBytesConsumed(QuicByteCount bytes) { | 
|  | if (type_ == CRYPTO) { | 
|  | // A stream with type CRYPTO has no flow control, so there's nothing this | 
|  | // function needs to do. This function still gets called by the | 
|  | // QuicStreamSequencers used by QuicCryptoStream. | 
|  | return; | 
|  | } | 
|  | // Only adjust stream level flow controller if still reading. | 
|  | if (!read_side_closed_) { | 
|  | flow_controller_->AddBytesConsumed(bytes); | 
|  | } | 
|  |  | 
|  | if (stream_contributes_to_connection_flow_control_) { | 
|  | connection_flow_controller_->AddBytesConsumed(bytes); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::UpdateSendWindowOffset(QuicStreamOffset new_window) { | 
|  | if (flow_controller_->UpdateSendWindowOffset(new_window)) { | 
|  | // Let session unblock this stream. | 
|  | session_->MarkConnectionLevelWriteBlocked(id_); | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::AddRandomPaddingAfterFin() { | 
|  | add_random_padding_after_fin_ = true; | 
|  | } | 
|  |  | 
|  | bool QuicStream::OnStreamFrameAcked(QuicStreamOffset offset, | 
|  | QuicByteCount data_length, | 
|  | bool fin_acked, | 
|  | QuicTime::Delta /*ack_delay_time*/, | 
|  | QuicByteCount* newly_acked_length) { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ << " Acking " | 
|  | << "[" << offset << ", " << offset + data_length << "]" | 
|  | << " fin = " << fin_acked; | 
|  | *newly_acked_length = 0; | 
|  | if (!send_buffer_.OnStreamDataAcked(offset, data_length, | 
|  | newly_acked_length)) { | 
|  | CloseConnectionWithDetails(QUIC_INTERNAL_ERROR, | 
|  | "Trying to ack unsent data."); | 
|  | return false; | 
|  | } | 
|  | if (!fin_sent_ && fin_acked) { | 
|  | CloseConnectionWithDetails(QUIC_INTERNAL_ERROR, | 
|  | "Trying to ack unsent fin."); | 
|  | return false; | 
|  | } | 
|  | // Indicates whether ack listener's OnPacketAcked should be called. | 
|  | const bool new_data_acked = | 
|  | *newly_acked_length > 0 || (fin_acked && fin_outstanding_); | 
|  | if (fin_acked) { | 
|  | fin_outstanding_ = false; | 
|  | fin_lost_ = false; | 
|  | } | 
|  | if (!IsWaitingForAcks()) { | 
|  | session_->OnStreamDoneWaitingForAcks(id_); | 
|  | } | 
|  | return new_data_acked; | 
|  | } | 
|  |  | 
|  | void QuicStream::OnStreamFrameRetransmitted(QuicStreamOffset offset, | 
|  | QuicByteCount data_length, | 
|  | bool fin_retransmitted) { | 
|  | send_buffer_.OnStreamDataRetransmitted(offset, data_length); | 
|  | if (fin_retransmitted) { | 
|  | fin_lost_ = false; | 
|  | } | 
|  | } | 
|  |  | 
|  | void QuicStream::OnStreamFrameLost(QuicStreamOffset offset, | 
|  | QuicByteCount data_length, | 
|  | bool fin_lost) { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ << " Losting " | 
|  | << "[" << offset << ", " << offset + data_length << "]" | 
|  | << " fin = " << fin_lost; | 
|  | if (data_length > 0) { | 
|  | send_buffer_.OnStreamDataLost(offset, data_length); | 
|  | } | 
|  | if (fin_lost && fin_outstanding_) { | 
|  | fin_lost_ = true; | 
|  | } | 
|  | } | 
|  |  | 
|  | bool QuicStream::RetransmitStreamData(QuicStreamOffset offset, | 
|  | QuicByteCount data_length, | 
|  | bool fin) { | 
|  | if (HasDeadlinePassed()) { | 
|  | OnDeadlinePassed(); | 
|  | return true; | 
|  | } | 
|  | QuicIntervalSet<QuicStreamOffset> retransmission(offset, | 
|  | offset + data_length); | 
|  | retransmission.Difference(bytes_acked()); | 
|  | bool retransmit_fin = fin && fin_outstanding_; | 
|  | if (retransmission.Empty() && !retransmit_fin) { | 
|  | return true; | 
|  | } | 
|  | QuicConsumedData consumed(0, false); | 
|  | for (const auto& interval : retransmission) { | 
|  | QuicStreamOffset retransmission_offset = interval.min(); | 
|  | QuicByteCount retransmission_length = interval.max() - interval.min(); | 
|  | const bool can_bundle_fin = | 
|  | retransmit_fin && (retransmission_offset + retransmission_length == | 
|  | stream_bytes_written()); | 
|  | consumed = session()->WritevData(this, id_, retransmission_length, | 
|  | retransmission_offset, | 
|  | can_bundle_fin ? FIN : NO_FIN); | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ | 
|  | << " is forced to retransmit stream data [" | 
|  | << retransmission_offset << ", " | 
|  | << retransmission_offset + retransmission_length | 
|  | << ") and fin: " << can_bundle_fin | 
|  | << ", consumed: " << consumed; | 
|  | OnStreamFrameRetransmitted(retransmission_offset, consumed.bytes_consumed, | 
|  | consumed.fin_consumed); | 
|  | if (can_bundle_fin) { | 
|  | retransmit_fin = !consumed.fin_consumed; | 
|  | } | 
|  | if (consumed.bytes_consumed < retransmission_length || | 
|  | (can_bundle_fin && !consumed.fin_consumed)) { | 
|  | // Connection is write blocked. | 
|  | return false; | 
|  | } | 
|  | } | 
|  | if (retransmit_fin) { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ | 
|  | << " retransmits fin only frame."; | 
|  | consumed = session()->WritevData(this, id_, 0, stream_bytes_written(), FIN); | 
|  | if (!consumed.fin_consumed) { | 
|  | return false; | 
|  | } | 
|  | } | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool QuicStream::IsWaitingForAcks() const { | 
|  | return (!rst_sent_ || stream_error_ == QUIC_STREAM_NO_ERROR) && | 
|  | (send_buffer_.stream_bytes_outstanding() || fin_outstanding_); | 
|  | } | 
|  |  | 
|  | size_t QuicStream::ReadableBytes() const { | 
|  | return sequencer_.ReadableBytes(); | 
|  | } | 
|  |  | 
|  | bool QuicStream::WriteStreamData(QuicStreamOffset offset, | 
|  | QuicByteCount data_length, | 
|  | QuicDataWriter* writer) { | 
|  | DCHECK_LT(0u, data_length); | 
|  | QUIC_DVLOG(2) << ENDPOINT << "Write stream " << id_ << " data from offset " | 
|  | << offset << " length " << data_length; | 
|  | return send_buffer_.WriteStreamData(offset, data_length, writer); | 
|  | } | 
|  |  | 
|  | void QuicStream::WriteBufferedData() { | 
|  | DCHECK(!write_side_closed_ && (HasBufferedData() || fin_buffered_)); | 
|  |  | 
|  | if (session_->ShouldYield(id())) { | 
|  | session_->MarkConnectionLevelWriteBlocked(id()); | 
|  | return; | 
|  | } | 
|  |  | 
|  | // Size of buffered data. | 
|  | size_t write_length = BufferedDataBytes(); | 
|  |  | 
|  | // A FIN with zero data payload should not be flow control blocked. | 
|  | bool fin_with_zero_data = (fin_buffered_ && write_length == 0); | 
|  |  | 
|  | bool fin = fin_buffered_; | 
|  |  | 
|  | // How much data flow control permits to be written. | 
|  | QuicByteCount send_window = flow_controller_->SendWindowSize(); | 
|  | if (stream_contributes_to_connection_flow_control_) { | 
|  | send_window = | 
|  | std::min(send_window, connection_flow_controller_->SendWindowSize()); | 
|  | } | 
|  |  | 
|  | if (send_window == 0 && !fin_with_zero_data) { | 
|  | // Quick return if nothing can be sent. | 
|  | MaybeSendBlocked(); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (write_length > send_window) { | 
|  | // Don't send the FIN unless all the data will be sent. | 
|  | fin = false; | 
|  |  | 
|  | // Writing more data would be a violation of flow control. | 
|  | write_length = static_cast<size_t>(send_window); | 
|  | QUIC_DVLOG(1) << "stream " << id() << " shortens write length to " | 
|  | << write_length << " due to flow control"; | 
|  | } | 
|  | session_->SetTransmissionType(NOT_RETRANSMISSION); | 
|  |  | 
|  | StreamSendingState state = fin ? FIN : NO_FIN; | 
|  | if (fin && add_random_padding_after_fin_) { | 
|  | state = FIN_AND_PADDING; | 
|  | } | 
|  | QuicConsumedData consumed_data = session_->WritevData( | 
|  | this, id(), write_length, stream_bytes_written(), state); | 
|  |  | 
|  | OnStreamDataConsumed(consumed_data.bytes_consumed); | 
|  |  | 
|  | AddBytesSent(consumed_data.bytes_consumed); | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ << " sends " | 
|  | << stream_bytes_written() << " bytes " | 
|  | << " and has buffered data " << BufferedDataBytes() << " bytes." | 
|  | << " fin is sent: " << consumed_data.fin_consumed | 
|  | << " fin is buffered: " << fin_buffered_; | 
|  |  | 
|  | // The write may have generated a write error causing this stream to be | 
|  | // closed. If so, simply return without marking the stream write blocked. | 
|  | if (write_side_closed_) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (consumed_data.bytes_consumed == write_length) { | 
|  | if (!fin_with_zero_data) { | 
|  | MaybeSendBlocked(); | 
|  | } | 
|  | if (fin && consumed_data.fin_consumed) { | 
|  | fin_sent_ = true; | 
|  | fin_outstanding_ = true; | 
|  | if (fin_received_) { | 
|  | session_->StreamDraining(id_); | 
|  | } | 
|  | CloseWriteSide(); | 
|  | } else if (fin && !consumed_data.fin_consumed) { | 
|  | session_->MarkConnectionLevelWriteBlocked(id()); | 
|  | } | 
|  | } else { | 
|  | session_->MarkConnectionLevelWriteBlocked(id()); | 
|  | } | 
|  | if (consumed_data.bytes_consumed > 0 || consumed_data.fin_consumed) { | 
|  | busy_counter_ = 0; | 
|  | } | 
|  |  | 
|  | if (IsWaitingForAcks()) { | 
|  | session_->OnStreamWaitingForAcks(id_); | 
|  | } | 
|  | } | 
|  |  | 
|  | uint64_t QuicStream::BufferedDataBytes() const { | 
|  | DCHECK_GE(send_buffer_.stream_offset(), stream_bytes_written()); | 
|  | return send_buffer_.stream_offset() - stream_bytes_written(); | 
|  | } | 
|  |  | 
|  | bool QuicStream::CanWriteNewData() const { | 
|  | return BufferedDataBytes() < buffered_data_threshold_; | 
|  | } | 
|  |  | 
|  | bool QuicStream::CanWriteNewDataAfterData(QuicByteCount length) const { | 
|  | return (BufferedDataBytes() + length) < buffered_data_threshold_; | 
|  | } | 
|  |  | 
|  | uint64_t QuicStream::stream_bytes_written() const { | 
|  | return send_buffer_.stream_bytes_written(); | 
|  | } | 
|  |  | 
|  | const QuicIntervalSet<QuicStreamOffset>& QuicStream::bytes_acked() const { | 
|  | return send_buffer_.bytes_acked(); | 
|  | } | 
|  |  | 
|  | void QuicStream::OnStreamDataConsumed(size_t bytes_consumed) { | 
|  | send_buffer_.OnStreamDataConsumed(bytes_consumed); | 
|  | } | 
|  |  | 
|  | void QuicStream::WritePendingRetransmission() { | 
|  | while (HasPendingRetransmission()) { | 
|  | QuicConsumedData consumed(0, false); | 
|  | if (!send_buffer_.HasPendingRetransmission()) { | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ | 
|  | << " retransmits fin only frame."; | 
|  | consumed = | 
|  | session()->WritevData(this, id_, 0, stream_bytes_written(), FIN); | 
|  | fin_lost_ = !consumed.fin_consumed; | 
|  | if (fin_lost_) { | 
|  | // Connection is write blocked. | 
|  | return; | 
|  | } | 
|  | } else { | 
|  | StreamPendingRetransmission pending = | 
|  | send_buffer_.NextPendingRetransmission(); | 
|  | // Determine whether the lost fin can be bundled with the data. | 
|  | const bool can_bundle_fin = | 
|  | fin_lost_ && | 
|  | (pending.offset + pending.length == stream_bytes_written()); | 
|  | consumed = | 
|  | session()->WritevData(this, id_, pending.length, pending.offset, | 
|  | can_bundle_fin ? FIN : NO_FIN); | 
|  | QUIC_DVLOG(1) << ENDPOINT << "stream " << id_ | 
|  | << " tries to retransmit stream data [" << pending.offset | 
|  | << ", " << pending.offset + pending.length | 
|  | << ") and fin: " << can_bundle_fin | 
|  | << ", consumed: " << consumed; | 
|  | OnStreamFrameRetransmitted(pending.offset, consumed.bytes_consumed, | 
|  | consumed.fin_consumed); | 
|  | if (consumed.bytes_consumed < pending.length || | 
|  | (can_bundle_fin && !consumed.fin_consumed)) { | 
|  | // Connection is write blocked. | 
|  | return; | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | bool QuicStream::MaybeSetTtl(QuicTime::Delta ttl) { | 
|  | if (is_static_) { | 
|  | QUIC_BUG << "Cannot set TTL of a static stream."; | 
|  | return false; | 
|  | } | 
|  | if (deadline_.IsInitialized()) { | 
|  | QUIC_DLOG(WARNING) << "Deadline has already been set."; | 
|  | return false; | 
|  | } | 
|  | QuicTime now = session()->connection()->clock()->ApproximateNow(); | 
|  | deadline_ = now + ttl; | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool QuicStream::HasDeadlinePassed() const { | 
|  | if (!deadline_.IsInitialized()) { | 
|  | // No deadline has been set. | 
|  | return false; | 
|  | } | 
|  | QuicTime now = session()->connection()->clock()->ApproximateNow(); | 
|  | if (now < deadline_) { | 
|  | return false; | 
|  | } | 
|  | // TTL expired. | 
|  | QUIC_DVLOG(1) << "stream " << id() << " deadline has passed"; | 
|  | return true; | 
|  | } | 
|  |  | 
|  | void QuicStream::OnDeadlinePassed() { | 
|  | Reset(QUIC_STREAM_TTL_EXPIRED); | 
|  | } | 
|  |  | 
|  | void QuicStream::SendStopSending(uint16_t code) { | 
|  | if (!VersionHasIetfQuicFrames(transport_version())) { | 
|  | // If the connection is not version 99, do nothing. | 
|  | // Do not QUIC_BUG or anything; the application really does not need to know | 
|  | // what version the connection is in. | 
|  | return; | 
|  | } | 
|  | session_->SendStopSending(code, id_); | 
|  | } | 
|  |  | 
|  | }  // namespace quic |