Move shared files in net/quic/ into net/quic/core/

net/quic/quic_stream_sequencer_buffer.cc

Index: net/quic/quic_stream_sequencer_buffer.cc
diff --git a/net/quic/quic_stream_sequencer_buffer.cc b/net/quic/quic_stream_sequencer_buffer.cc
deleted file mode 100644
index 352db230dc6fffa32c78fe00bf5aee0e9ecab3ba..0000000000000000000000000000000000000000
--- a/net/quic/quic_stream_sequencer_buffer.cc
+++ /dev/null
@@ -1,505 +0,0 @@
-// Copyright (c) 2015 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/quic/quic_stream_sequencer_buffer.h"
-
-#include "base/logging.h"
-#include "base/strings/string_number_conversions.h"
-#include "net/quic/quic_bug_tracker.h"
-
-using std::min;
-using std::string;
-
-namespace net {
-
-namespace {
-
-string RangeDebugString(QuicStreamOffset start, QuicStreamOffset end) {
-  return string("[") + base::Uint64ToString(start) + ", " +
-         base::Uint64ToString(end) + ") ";
-}
-
-}  // namespace
-
-QuicStreamSequencerBuffer::Gap::Gap(QuicStreamOffset begin_offset,
-                                    QuicStreamOffset end_offset)
-    : begin_offset(begin_offset), end_offset(end_offset) {}
-
-QuicStreamSequencerBuffer::FrameInfo::FrameInfo()
-    : length(1), timestamp(QuicTime::Zero()) {}
-
-QuicStreamSequencerBuffer::FrameInfo::FrameInfo(size_t length,
-                                                QuicTime timestamp)
-    : length(length), timestamp(timestamp) {}
-
-QuicStreamSequencerBuffer::QuicStreamSequencerBuffer(size_t max_capacity_bytes)
-    : max_buffer_capacity_bytes_(max_capacity_bytes),
-      blocks_count_(
-          ceil(static_cast<double>(max_capacity_bytes) / kBlockSizeBytes)),
-      total_bytes_read_(0),
-      blocks_(blocks_count_) {
-  Clear();
-}
-
-QuicStreamSequencerBuffer::~QuicStreamSequencerBuffer() {
-  Clear();
-}
-
-void QuicStreamSequencerBuffer::Clear() {
-  for (size_t i = 0; i < blocks_count_; ++i) {
-    if (blocks_[i] != nullptr) {
-      RetireBlock(i);
-    }
-  }
-  num_bytes_buffered_ = 0;
-  // Reset gaps_ so that buffer is in a state as if all data before
-  // total_bytes_read_ has been consumed, and those after total_bytes_read_
-  // has never arrived.
-  gaps_ = std::list<Gap>(
-      1, Gap(total_bytes_read_, std::numeric_limits<QuicStreamOffset>::max())),
-  frame_arrival_time_map_.clear();
-}
-
-void QuicStreamSequencerBuffer::RetireBlock(size_t idx) {
-  DCHECK(blocks_[idx] != nullptr);
-  delete blocks_[idx];
-  blocks_[idx] = nullptr;
-  DVLOG(1) << "Retired block with index: " << idx;
-}
-
-QuicErrorCode QuicStreamSequencerBuffer::OnStreamData(
-    QuicStreamOffset starting_offset,
-    base::StringPiece data,
-    QuicTime timestamp,
-    size_t* const bytes_buffered,
-    std::string* error_details) {
-  *bytes_buffered = 0;
-  QuicStreamOffset offset = starting_offset;
-  size_t size = data.size();
-  if (size == 0) {
-    *error_details = "Received empty stream frame without FIN.";
-    return QUIC_EMPTY_STREAM_FRAME_NO_FIN;
-  }
-
-  // Find the first gap not ending before |offset|. This gap maybe the gap to
-  // fill if the arriving frame doesn't overlaps with previous ones.
-  std::list<Gap>::iterator current_gap = gaps_.begin();
-  while (current_gap != gaps_.end() && current_gap->end_offset <= offset) {
-    ++current_gap;
-  }
-
-  DCHECK(current_gap != gaps_.end());
-
-  // "duplication": might duplicate with data alread filled,but also might
-  // overlap across different base::StringPiece objects already written.
-  // In both cases, don't write the data,
-  // and allow the caller of this method to handle the result.
-  if (offset < current_gap->begin_offset &&
-      offset + size <= current_gap->begin_offset) {
-    DVLOG(1) << "Duplicated data at offset: " << offset << " length: " << size;
-    return QUIC_NO_ERROR;
-  }
-  if (offset < current_gap->begin_offset &&
-      offset + size > current_gap->begin_offset) {
-    // Beginning of new data overlaps data before current gap.
-    *error_details =
-        string("Beginning of received data overlaps with buffered data.\n") +
-        "New frame range " + RangeDebugString(offset, offset + size) +
-        " with first 128 bytes: " +
-        string(data.data(), data.length() < 128 ? data.length() : 128) +
-        "\nCurrently received frames: " + ReceivedFramesDebugString() +
-        "\nCurrent gaps: " + GapsDebugString();
-    return QUIC_OVERLAPPING_STREAM_DATA;
-  }
-  if (offset + size > current_gap->end_offset) {
-    // End of new data overlaps with data after current gap.
-    *error_details =
-        string("End of received data overlaps with buffered data.\n") +
-        "New frame range " + RangeDebugString(offset, offset + size) +
-        " with first 128 bytes: " +
-        string(data.data(), data.length() < 128 ? data.length() : 128) +
-        "\nCurrently received frames: " + ReceivedFramesDebugString() +
-        "\nCurrent gaps: " + GapsDebugString();
-    return QUIC_OVERLAPPING_STREAM_DATA;
-  }
-
-  // Write beyond the current range this buffer is covering.
-  if (offset + size > total_bytes_read_ + max_buffer_capacity_bytes_) {
-    *error_details = "Received data beyond available range.";
-    return QUIC_INTERNAL_ERROR;
-  }
-
-  size_t total_written = 0;
-  size_t source_remaining = size;
-  const char* source = data.data();
-  // Write data block by block. If corresponding block has not created yet,
-  // create it first.
-  // Stop when all data are written or reaches the logical end of the buffer.
-  while (source_remaining > 0) {
-    const size_t write_block_num = GetBlockIndex(offset);
-    const size_t write_block_offset = GetInBlockOffset(offset);
-    DCHECK_GT(blocks_count_, write_block_num);
-
-    size_t block_capacity = GetBlockCapacity(write_block_num);
-    size_t bytes_avail = block_capacity - write_block_offset;
-
-    // If this write meets the upper boundary of the buffer,
-    // reduce the available free bytes.
-    if (offset + bytes_avail > total_bytes_read_ + max_buffer_capacity_bytes_) {
-      bytes_avail = total_bytes_read_ + max_buffer_capacity_bytes_ - offset;
-    }
-
-    if (blocks_[write_block_num] == nullptr) {
-      // TODO(danzh): Investigate if using a freelist would improve performance.
-      // Same as RetireBlock().
-      blocks_[write_block_num] = new BufferBlock();
-    }
-
-    const size_t bytes_to_copy = min<size_t>(bytes_avail, source_remaining);
-    char* dest = blocks_[write_block_num]->buffer + write_block_offset;
-    DVLOG(1) << "Write at offset: " << offset << " length: " << bytes_to_copy;
-    memcpy(dest, source, bytes_to_copy);
-    source += bytes_to_copy;
-    source_remaining -= bytes_to_copy;
-    offset += bytes_to_copy;
-    total_written += bytes_to_copy;
-  }
-
-  DCHECK_GT(total_written, 0u);
-  *bytes_buffered = total_written;
-  UpdateGapList(current_gap, starting_offset, total_written);
-
-  frame_arrival_time_map_.insert(
-      std::make_pair(starting_offset, FrameInfo(size, timestamp)));
-  num_bytes_buffered_ += total_written;
-  return QUIC_NO_ERROR;
-}
-
-inline void QuicStreamSequencerBuffer::UpdateGapList(
-    std::list<Gap>::iterator gap_with_new_data_written,
-    QuicStreamOffset start_offset,
-    size_t bytes_written) {
-  if (gap_with_new_data_written->begin_offset == start_offset &&
-      gap_with_new_data_written->end_offset > start_offset + bytes_written) {
-    // New data has been written into the left part of the buffer.
-    gap_with_new_data_written->begin_offset = start_offset + bytes_written;
-  } else if (gap_with_new_data_written->begin_offset < start_offset &&
-             gap_with_new_data_written->end_offset ==
-                 start_offset + bytes_written) {
-    // New data has been written into the right part of the buffer.
-    gap_with_new_data_written->end_offset = start_offset;
-  } else if (gap_with_new_data_written->begin_offset < start_offset &&
-             gap_with_new_data_written->end_offset >
-                 start_offset + bytes_written) {
-    // New data has been written into the middle of the buffer.
-    auto current = gap_with_new_data_written++;
-    QuicStreamOffset current_end = current->end_offset;
-    current->end_offset = start_offset;
-    gaps_.insert(gap_with_new_data_written,
-                 Gap(start_offset + bytes_written, current_end));
-  } else if (gap_with_new_data_written->begin_offset == start_offset &&
-             gap_with_new_data_written->end_offset ==
-                 start_offset + bytes_written) {
-    // This gap has been filled with new data. So it's no longer a gap.
-    gaps_.erase(gap_with_new_data_written);
-  }
-}
-
-size_t QuicStreamSequencerBuffer::Readv(const iovec* dest_iov,
-                                        size_t dest_count) {
-  size_t bytes_read = 0;
-  for (size_t i = 0; i < dest_count && ReadableBytes() > 0; ++i) {
-    char* dest = reinterpret_cast<char*>(dest_iov[i].iov_base);
-    size_t dest_remaining = dest_iov[i].iov_len;
-    while (dest_remaining > 0 && ReadableBytes() > 0) {
-      size_t block_idx = NextBlockToRead();
-      size_t start_offset_in_block = ReadOffset();
-      size_t block_capacity = GetBlockCapacity(block_idx);
-      size_t bytes_available_in_block =
-          min<size_t>(ReadableBytes(), block_capacity - start_offset_in_block);
-      size_t bytes_to_copy =
-          min<size_t>(bytes_available_in_block, dest_remaining);
-      DCHECK_GT(bytes_to_copy, 0u);
-      DCHECK_NE(static_cast<BufferBlock*>(nullptr), blocks_[block_idx]);
-      memcpy(dest, blocks_[block_idx]->buffer + start_offset_in_block,
-             bytes_to_copy);
-      dest += bytes_to_copy;
-      dest_remaining -= bytes_to_copy;
-      num_bytes_buffered_ -= bytes_to_copy;
-      total_bytes_read_ += bytes_to_copy;
-      bytes_read += bytes_to_copy;
-
-      // Retire the block if all the data is read out
-      // and no other data is stored in this block.
-      if (bytes_to_copy == bytes_available_in_block) {
-        RetireBlockIfEmpty(block_idx);
-      }
-    }
-  }
-
-  if (bytes_read > 0) {
-    UpdateFrameArrivalMap(total_bytes_read_);
-  }
-  return bytes_read;
-}
-
-int QuicStreamSequencerBuffer::GetReadableRegions(struct iovec* iov,
-                                                  int iov_count) const {
-  DCHECK(iov != nullptr);
-  DCHECK_GT(iov_count, 0);
-
-  if (ReadableBytes() == 0) {
-    iov[0].iov_base = nullptr;
-    iov[0].iov_len = 0;
-    return 0;
-  }
-
-  size_t start_block_idx = NextBlockToRead();
-  QuicStreamOffset readable_offset_end = gaps_.front().begin_offset - 1;
-  DCHECK_GE(readable_offset_end + 1, total_bytes_read_);
-  size_t end_block_offset = GetInBlockOffset(readable_offset_end);
-  size_t end_block_idx = GetBlockIndex(readable_offset_end);
-
-  // If readable region is within one block, deal with it seperately.
-  if (start_block_idx == end_block_idx && ReadOffset() <= end_block_offset) {
-    iov[0].iov_base = blocks_[start_block_idx]->buffer + ReadOffset();
-    iov[0].iov_len = ReadableBytes();
-    DVLOG(1) << "Got only a single block with index: " << start_block_idx;
-    return 1;
-  }
-
-  // Get first block
-  iov[0].iov_base = blocks_[start_block_idx]->buffer + ReadOffset();
-  iov[0].iov_len = GetBlockCapacity(start_block_idx) - ReadOffset();
-  DVLOG(1) << "Got first block " << start_block_idx << " with len "
-           << iov[0].iov_len;
-  DCHECK_GT(readable_offset_end + 1, total_bytes_read_ + iov[0].iov_len)
-      << "there should be more available data";
-
-  // Get readable regions of the rest blocks till either 2nd to last block
-  // before gap is met or |iov| is filled. For these blocks, one whole block is
-  // a region.
-  int iov_used = 1;
-  size_t block_idx = (start_block_idx + iov_used) % blocks_count_;
-  while (block_idx != end_block_idx && iov_used < iov_count) {
-    DCHECK_NE(static_cast<BufferBlock*>(nullptr), blocks_[block_idx]);
-    iov[iov_used].iov_base = blocks_[block_idx]->buffer;
-    iov[iov_used].iov_len = GetBlockCapacity(block_idx);
-    DVLOG(1) << "Got block with index: " << block_idx;
-    ++iov_used;
-    block_idx = (start_block_idx + iov_used) % blocks_count_;
-  }
-
-  // Deal with last block if |iov| can hold more.
-  if (iov_used < iov_count) {
-    DCHECK_NE(static_cast<BufferBlock*>(nullptr), blocks_[block_idx]);
-    iov[iov_used].iov_base = blocks_[end_block_idx]->buffer;
-    iov[iov_used].iov_len = end_block_offset + 1;
-    DVLOG(1) << "Got last block with index: " << end_block_idx;
-    ++iov_used;
-  }
-  return iov_used;
-}
-
-bool QuicStreamSequencerBuffer::GetReadableRegion(iovec* iov,
-                                                  QuicTime* timestamp) const {
-  if (ReadableBytes() == 0) {
-    iov[0].iov_base = nullptr;
-    iov[0].iov_len = 0;
-    return false;
-  }
-
-  size_t start_block_idx = NextBlockToRead();
-  iov->iov_base = blocks_[start_block_idx]->buffer + ReadOffset();
-  size_t readable_bytes_in_block = min<size_t>(
-      GetBlockCapacity(start_block_idx) - ReadOffset(), ReadableBytes());
-  size_t region_len = 0;
-  auto iter = frame_arrival_time_map_.begin();
-  *timestamp = iter->second.timestamp;
-  DVLOG(1) << "Readable bytes in block: " << readable_bytes_in_block;
-  for (; iter != frame_arrival_time_map_.end() &&
-         region_len + iter->second.length <= readable_bytes_in_block;
-       ++iter) {
-    if (iter->second.timestamp != *timestamp) {
-      // If reaches a frame arrive at another timestamp, stop expanding current
-      // region.
-      DVLOG(1) << "Meet frame with different timestamp.";
-      break;
-    }
-    region_len += iter->second.length;
-    DVLOG(1) << "Added bytes to region: " << iter->second.length;
-  }
-  if (iter == frame_arrival_time_map_.end() ||
-      iter->second.timestamp == *timestamp) {
-    // If encountered the end of readable bytes before reaching a different
-    // timestamp.
-    DVLOG(1) << "Got all readable bytes in first block.";
-    region_len = readable_bytes_in_block;
-  }
-  iov->iov_len = region_len;
-  return true;
-}
-
-bool QuicStreamSequencerBuffer::MarkConsumed(size_t bytes_used) {
-  if (bytes_used > ReadableBytes()) {
-    return false;
-  }
-  size_t bytes_to_consume = bytes_used;
-  while (bytes_to_consume > 0) {
-    size_t block_idx = NextBlockToRead();
-    size_t offset_in_block = ReadOffset();
-    size_t bytes_available = min<size_t>(
-        ReadableBytes(), GetBlockCapacity(block_idx) - offset_in_block);
-    size_t bytes_read = min<size_t>(bytes_to_consume, bytes_available);
-    total_bytes_read_ += bytes_read;
-    num_bytes_buffered_ -= bytes_read;
-    bytes_to_consume -= bytes_read;
-    // If advanced to the end of current block and end of buffer hasn't wrapped
-    // to this block yet.
-    if (bytes_available == bytes_read) {
-      RetireBlockIfEmpty(block_idx);
-    }
-  }
-  if (bytes_used > 0) {
-    UpdateFrameArrivalMap(total_bytes_read_);
-  }
-  return true;
-}
-
-size_t QuicStreamSequencerBuffer::FlushBufferedFrames() {
-  size_t prev_total_bytes_read = total_bytes_read_;
-  total_bytes_read_ = gaps_.back().begin_offset;
-  Clear();
-  return total_bytes_read_ - prev_total_bytes_read;
-}
-
-size_t QuicStreamSequencerBuffer::ReadableBytes() const {
-  return gaps_.front().begin_offset - total_bytes_read_;
-}
-
-bool QuicStreamSequencerBuffer::HasBytesToRead() const {
-  return ReadableBytes() > 0;
-}
-
-QuicStreamOffset QuicStreamSequencerBuffer::BytesConsumed() const {
-  return total_bytes_read_;
-}
-
-size_t QuicStreamSequencerBuffer::BytesBuffered() const {
-  return num_bytes_buffered_;
-}
-
-size_t QuicStreamSequencerBuffer::GetBlockIndex(QuicStreamOffset offset) const {
-  return (offset % max_buffer_capacity_bytes_) / kBlockSizeBytes;
-}
-
-size_t QuicStreamSequencerBuffer::GetInBlockOffset(
-    QuicStreamOffset offset) const {
-  return (offset % max_buffer_capacity_bytes_) % kBlockSizeBytes;
-}
-
-size_t QuicStreamSequencerBuffer::ReadOffset() const {
-  return GetInBlockOffset(total_bytes_read_);
-}
-
-size_t QuicStreamSequencerBuffer::NextBlockToRead() const {
-  return GetBlockIndex(total_bytes_read_);
-}
-
-void QuicStreamSequencerBuffer::RetireBlockIfEmpty(size_t block_index) {
-  DCHECK(ReadableBytes() == 0 || GetInBlockOffset(total_bytes_read_) == 0)
-      << "RetireBlockIfEmpty() should only be called when advancing to next "
-         "block"
-         " or a gap has been reached.";
-  // If the whole buffer becomes empty, the last piece of data has been read.
-  if (Empty()) {
-    RetireBlock(block_index);
-    return;
-  }
-
-  // Check where the logical end of this buffer is.
-  // Not empty if the end of circular buffer has been wrapped to this block.
-  if (GetBlockIndex(gaps_.back().begin_offset - 1) == block_index) {
-    return;
-  }
-
-  // Read index remains in this block, which means a gap has been reached.
-  if (NextBlockToRead() == block_index) {
-    Gap first_gap = gaps_.front();
-    DCHECK(first_gap.begin_offset == total_bytes_read_);
-    // Check where the next piece data is.
-    // Not empty if next piece of data is still in this chunk.
-    bool gap_extends_to_infinity =
-        (first_gap.end_offset != std::numeric_limits<QuicStreamOffset>::max());
-    bool gap_ends_in_this_block =
-        (GetBlockIndex(first_gap.end_offset) == block_index);
-    if (gap_extends_to_infinity || gap_ends_in_this_block) {
-      return;
-    }
-  }
-  RetireBlock(block_index);
-}
-
-bool QuicStreamSequencerBuffer::Empty() const {
-  return gaps_.size() == 1 && gaps_.front().begin_offset == total_bytes_read_;
-}
-
-size_t QuicStreamSequencerBuffer::GetBlockCapacity(size_t block_index) const {
-  if ((block_index + 1) == blocks_count_) {
-    size_t result = max_buffer_capacity_bytes_ % kBlockSizeBytes;
-    if (result == 0) {  // whole block
-      result = kBlockSizeBytes;
-    }
-    return result;
-  } else {
-    return kBlockSizeBytes;
-  }
-}
-
-void QuicStreamSequencerBuffer::UpdateFrameArrivalMap(QuicStreamOffset offset) {
-  // Get the frame before which all frames should be removed.
-  auto next_frame = frame_arrival_time_map_.upper_bound(offset);
-  DCHECK(next_frame != frame_arrival_time_map_.begin());
-  auto iter = frame_arrival_time_map_.begin();
-  while (iter != next_frame) {
-    auto erased = *iter;
-    iter = frame_arrival_time_map_.erase(iter);
-    DVLOG(1) << "Removed FrameInfo with offset: " << erased.first
-             << " and length: " << erased.second.length;
-    if (erased.first + erased.second.length > offset) {
-      // If last frame is partially read out, update this FrameInfo and insert
-      // it back.
-      auto updated = std::make_pair(
-          offset, FrameInfo(erased.first + erased.second.length - offset,
-                            erased.second.timestamp));
-      DVLOG(1) << "Inserted FrameInfo with offset: " << updated.first
-               << " and length: " << updated.second.length;
-      frame_arrival_time_map_.insert(updated);
-    }
-  }
-}
-
-string QuicStreamSequencerBuffer::GapsDebugString() {
-  string current_gaps_string;
-  for (const Gap& gap : gaps_) {
-    QuicStreamOffset current_gap_begin = gap.begin_offset;
-    QuicStreamOffset current_gap_end = gap.end_offset;
-    current_gaps_string += RangeDebugString(current_gap_begin, current_gap_end);
-  }
-  return current_gaps_string;
-}
-
-string QuicStreamSequencerBuffer::ReceivedFramesDebugString() {
-  string current_frames_string;
-  for (auto it : frame_arrival_time_map_) {
-    QuicStreamOffset current_frame_begin_offset = it.first;
-    QuicStreamOffset current_frame_end_offset =
-        it.second.length + current_frame_begin_offset;
-    current_frames_string +=
-        RangeDebugString(current_frame_begin_offset, current_frame_end_offset);
-  }
-  return current_frames_string;
-}
-
-}  //  namespace net