Remove obsolete fields in quic_protocol and their current usage in QUIC. Reorders QuicAckFrame fie…

net/quic/quic_fec_group.cc

-// 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/quic/quic_fec_group.h"
-
-#include <limits>
-
-#include "base/logging.h"
-#include "base/stl_util.h"
-
-using base::StringPiece;
-using std::numeric_limits;
-using std::set;
-
-namespace net {
-
-QuicFecGroup::QuicFecGroup(QuicPacketNumber fec_group_number)
-    : QuicFecGroupInterface(),
-      min_protected_packet_(fec_group_number),
-      max_protected_packet_(kInvalidPacketNumber),
-      payload_parity_len_(0),
-      effective_encryption_level_(NUM_ENCRYPTION_LEVELS) {}
-
-QuicFecGroup::~QuicFecGroup() {}
-
-bool QuicFecGroup::Update(EncryptionLevel encryption_level,
-                          const QuicPacketHeader& header,
-                          StringPiece decrypted_payload) {
-  DCHECK_EQ(min_protected_packet_, header.fec_group);
-  DCHECK_NE(kInvalidPacketNumber, header.packet_number);
-  if (ContainsKey(received_packets_, header.packet_number)) {
-    return false;
-  }
-  if (header.packet_number < min_protected_packet_ ||
-      (has_received_fec_packet() &&
-       header.packet_number > max_protected_packet_)) {
-    DLOG(ERROR) << "FEC group does not cover received packet: "
-                << header.packet_number;
-    return false;
-  }
-  if (!UpdateParity(decrypted_payload)) {
-    return false;
-  }
-  received_packets_.insert(header.packet_number);
-  if (encryption_level < effective_encryption_level_) {
-    effective_encryption_level_ = encryption_level;
-  }
-  return true;
-}
-
-bool QuicFecGroup::UpdateFec(EncryptionLevel encryption_level,
-                             const QuicPacketHeader& header,
-                             StringPiece redundancy) {
-  DCHECK_EQ(min_protected_packet_, header.fec_group);
-  DCHECK_NE(kInvalidPacketNumber, header.packet_number);
-  if (has_received_fec_packet()) {
-    return false;
-  }
-  for (QuicPacketNumber packet : received_packets_) {
-    if (packet >= header.packet_number) {
-      DLOG(ERROR) << "FEC group does not cover received packet: " << packet;
-      return false;
-    }
-  }
-  if (!UpdateParity(redundancy)) {
-    return false;
-  }
-  max_protected_packet_ = header.packet_number - 1;
-  if (encryption_level < effective_encryption_level_) {
-    effective_encryption_level_ = encryption_level;
-  }
-  return true;
-}
-
-bool QuicFecGroup::CanRevive() const {
-  // We can revive if we're missing exactly 1 packet.
-  return NumMissingPackets() == 1;
-}
-
-bool QuicFecGroup::IsFinished() const {
-  // We are finished if we are not missing any packets.
-  return NumMissingPackets() == 0;
-}
-
-size_t QuicFecGroup::Revive(QuicPacketHeader* header,
-                            char* decrypted_payload,
-                            size_t decrypted_payload_len) {
-  if (!CanRevive()) {
-    return 0;
-  }
-
-  // Identify the packet number to be resurrected.
-  QuicPacketNumber missing = kInvalidPacketNumber;
-  for (QuicPacketNumber i = min_protected_packet_; i <= max_protected_packet_;
-       ++i) {
-    // Is this packet missing?
-    if (received_packets_.count(i) == 0) {
-      missing = i;
-      break;
-    }
-  }
-  DCHECK_NE(kInvalidPacketNumber, missing);
-
-  DCHECK_LE(payload_parity_len_, decrypted_payload_len);
-  if (payload_parity_len_ > decrypted_payload_len) {
-    return 0;
-  }
-  for (size_t i = 0; i < payload_parity_len_; ++i) {
-    decrypted_payload[i] = payload_parity_[i];
-  }
-
-  header->packet_number = missing;
-  header->entropy_flag = false;  // Unknown entropy.
-
-  received_packets_.insert(missing);
-  return payload_parity_len_;
-}
-
-bool QuicFecGroup::IsWaitingForPacketBefore(QuicPacketNumber num) const {
-  // Entire range is larger than the threshold.
-  if (min_protected_packet_ >= num) {
-    return false;
-  }
-
-  // Entire range is smaller than the threshold.
-  if (received_packets_.size() > 0 ? *received_packets_.rbegin() + 1 < num
-                                   : min_protected_packet_ < num) {
-    return true;
-  }
-
-  // Range spans the threshold so look for a missing packet below the threshold.
-  QuicPacketNumber target = min_protected_packet_;
-  for (QuicPacketNumber packet : received_packets_) {
-    if (target++ != packet) {
-      return true;
-    }
-    if (target >= num) {
-      return false;
-    }
-  }
-
-  // No missing packets below the threshold.
-  return false;
-}
-
-bool QuicFecGroup::UpdateParity(StringPiece payload) {
-  DCHECK_GE(kMaxPacketSize, payload.size());
-  if (payload.size() > kMaxPacketSize) {
-    DLOG(ERROR) << "Illegal payload size: " << payload.size();
-    return false;
-  }
-  if (payload_parity_len_ < payload.size()) {
-    payload_parity_len_ = payload.size();
-  }
-  if (received_packets_.empty() && !has_received_fec_packet()) {
-    // Initialize the parity to the value of this payload
-    memcpy(payload_parity_, payload.data(), payload.size());
-    if (payload.size() < kMaxPacketSize) {
-      // TODO(rch): expand as needed.
-      memset(payload_parity_ + payload.size(), 0,
-             kMaxPacketSize - payload.size());
-    }
-    return true;
-  }
-  // Update the parity by XORing in the data (padding with 0s if necessary).
-  XorBuffers(payload.data(), payload.size(), payload_parity_);
-  return true;
-}
-
-QuicPacketCount QuicFecGroup::NumMissingPackets() const {
-  if (!has_received_fec_packet()) {
-    return numeric_limits<QuicPacketCount>::max();
-  }
-  return static_cast<QuicPacketCount>(
-      (max_protected_packet_ - min_protected_packet_ + 1) -
-      received_packets_.size());
-}
-
-const StringPiece QuicFecGroup::PayloadParity() const {
-  return StringPiece(payload_parity_, payload_parity_len_);
-}
-
-QuicPacketCount QuicFecGroup::NumReceivedPackets() const {
-  return received_packets_.size();
-}
-
-EncryptionLevel QuicFecGroup::EffectiveEncryptionLevel() const {
-  return effective_encryption_level_;
-}
-
-QuicFecGroupNumber QuicFecGroup::FecGroupNumber() const {
-  return min_protected_packet_;
-}
-
-}  // namespace net