Add a merely pass-through QuicMultipathSentPacketManager. Protected behind blocked flag FLAGS_quic_…

net/quic/quic_multipath_sent_packet_manager.cc

Index: net/quic/quic_multipath_sent_packet_manager.cc
diff --git a/net/quic/quic_multipath_sent_packet_manager.cc b/net/quic/quic_multipath_sent_packet_manager.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0e5e296d80592abdb99831846a50de1972ee35e6
--- /dev/null
+++ b/net/quic/quic_multipath_sent_packet_manager.cc
@@ -0,0 +1,520 @@
+#include "net/quic/quic_multipath_sent_packet_manager.h"

[Zhongyi Shi, 2016/07/25 22:30:34]

ditto

+
+#include <cstdint>
+
+#include "base/strings/string_number_conversions.h"
+#include "net/quic/quic_bug_tracker.h"
+
+using std::string;
+using std::max;
+
+namespace net {
+
+QuicMultipathSentPacketManager::QuicMultipathSentPacketManager(
+    QuicSentPacketManagerInterface* manager,
+    QuicConnectionCloseDelegateInterface* delegate)
+    : delegate_(delegate) {
+  path_managers_info_.push_back(PathSentPacketManagerInfo(manager, ACTIVE));
+}
+
+QuicMultipathSentPacketManager::~QuicMultipathSentPacketManager() {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    delete path_manager_info.manager;
+  }
+}
+
+void QuicMultipathSentPacketManager::SetFromConfig(const QuicConfig& config) {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager != nullptr) {
+      path_manager_info.manager->SetFromConfig(config);
+    }
+  }
+}
+
+void QuicMultipathSentPacketManager::ResumeConnectionState(
+    const CachedNetworkParameters& cached_network_params,
+    bool max_bandwidth_resumption) {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(kDefaultPathId);
+    return;
+  }
+  path_manager->ResumeConnectionState(cached_network_params,
+                                      max_bandwidth_resumption);
+}
+
+void QuicMultipathSentPacketManager::SetNumOpenStreams(size_t num_streams) {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager != nullptr) {
+      path_manager_info.manager->SetNumOpenStreams(num_streams);
+    }
+  }
+}
+
+void QuicMultipathSentPacketManager::SetMaxPacingRate(
+    QuicBandwidth max_pacing_rate) {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(kDefaultPathId);
+    return;
+  }
+  path_manager->SetMaxPacingRate(max_pacing_rate);
+}
+
+void QuicMultipathSentPacketManager::SetHandshakeConfirmed() {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(kDefaultPathId);
+    return;
+  }
+  path_manager->SetHandshakeConfirmed();
+}
+
+void QuicMultipathSentPacketManager::OnIncomingAck(
+    const QuicAckFrame& ack_frame,
+    QuicTime ack_receive_time) {
+  if (ack_frame.path_id >= path_managers_info_.size() ||
+      path_managers_info_[ack_frame.path_id].state != ACTIVE) {
+    return;
+  }
+  path_managers_info_[ack_frame.path_id].manager->OnIncomingAck(
+      ack_frame, ack_receive_time);
+}
+
+bool QuicMultipathSentPacketManager::IsUnacked(
+    QuicPathId path_id,
+    QuicPacketNumber packet_number) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  return path_manager != nullptr &&
+         path_manager->IsUnacked(path_id, packet_number);
+}
+
+bool QuicMultipathSentPacketManager::HasRetransmittableFrames(
+    QuicPathId path_id,
+    QuicPacketNumber packet_number) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  return path_manager != nullptr &&
+         path_manager->HasRetransmittableFrames(path_id, packet_number);
+}
+
+void QuicMultipathSentPacketManager::RetransmitUnackedPackets(
+    TransmissionType retransmission_type) {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(kDefaultPathId);
+    return;
+  }
+  path_manager->RetransmitUnackedPackets(retransmission_type);
+}
+
+bool QuicMultipathSentPacketManager::MaybeRetransmitTailLossProbe() {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager != nullptr &&
+        path_manager_info.state == ACTIVE) {
+      if (path_manager_info.manager->MaybeRetransmitTailLossProbe()) {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+void QuicMultipathSentPacketManager::NeuterUnencryptedPackets() {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(kDefaultPathId);
+    return;
+  }
+  path_manager->NeuterUnencryptedPackets();
+}
+
+bool QuicMultipathSentPacketManager::HasPendingRetransmissions() const {
+  // TODO(fayang): Move pending_retransmissions_ from path sent packet manager
+  // to multipath sent packet manager.
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  return path_manager != nullptr && path_manager->HasPendingRetransmissions();
+}
+
+PendingRetransmission
+QuicMultipathSentPacketManager::NextPendingRetransmission() {
+  // TODO(fayang): Move pending_retransmissions_ from path sent packet manager
+  // to multipath sent packet manager.
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(kDefaultPathId);
+    QuicFrames retransmittable_frames;
+    return PendingRetransmission(kInvalidPathId, 0u, NOT_RETRANSMISSION,
+                                 retransmittable_frames, false, 0,
+                                 ENCRYPTION_NONE, PACKET_1BYTE_PACKET_NUMBER);
+  }
+  return path_manager->NextPendingRetransmission();
+}
+
+bool QuicMultipathSentPacketManager::HasUnackedPackets() const {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager != nullptr &&
+        path_manager_info.state == ACTIVE &&
+        path_manager_info.manager->HasUnackedPackets()) {
+      return true;
+    }
+  }
+  return false;
+}
+
+QuicPacketNumber QuicMultipathSentPacketManager::GetLeastUnacked(
+    QuicPathId path_id) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetLeastUnacked(path_id);
+}
+
+bool QuicMultipathSentPacketManager::OnPacketSent(
+    SerializedPacket* serialized_packet,
+    QuicPathId original_path_id,
+    QuicPacketNumber original_packet_number,
+    QuicTime sent_time,
+    TransmissionType transmission_type,
+    HasRetransmittableData has_retransmittable_data) {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(serialized_packet->path_id);
+  // TODO(fayang): Handle packets retransmitted on different path.
+  DCHECK(original_packet_number == 0 ||
+         original_path_id == serialized_packet->path_id);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(serialized_packet->path_id);
+    return false;
+  }
+
+  return path_manager->OnPacketSent(
+      serialized_packet, original_path_id, original_packet_number, sent_time,
+      transmission_type, has_retransmittable_data);
+}
+
+void QuicMultipathSentPacketManager::OnRetransmissionTimeout() {
+  QuicPathId rto_path = DetermineRetransmissionTimeoutPath();
+  DCHECK_NE(kInvalidPathId, rto_path);
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(rto_path);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(rto_path);
+    return;
+  }
+  path_manager->OnRetransmissionTimeout();
+}
+
+QuicTime::Delta QuicMultipathSentPacketManager::TimeUntilSend(
+    QuicTime now,
+    HasRetransmittableData retransmittable,
+    QuicPathId* path_id) {
+  QuicTime::Delta delay = QuicTime::Delta::Infinite();
+  *path_id = kInvalidPathId;
+  for (size_t i = 0; i < path_managers_info_.size(); ++i) {
+    if (path_managers_info_[i].manager == nullptr ||
+        path_managers_info_[i].state != ACTIVE) {
+      continue;
+    }
+
+    QuicTime::Delta path_delay = path_managers_info_[i].manager->TimeUntilSend(
+        now, retransmittable, path_id);
+    if (!path_delay.IsInfinite() && path_delay < delay) {
+      delay = path_delay;
+      *path_id = i;
+    }
+  }
+  DCHECK(*path_id == kInvalidPathId || !delay.IsInfinite());
+  return delay;
+}
+
+const QuicTime QuicMultipathSentPacketManager::GetRetransmissionTime() const {
+  QuicTime retransmission_time = QuicTime::Zero();
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager == nullptr ||
+        path_manager_info.state != ACTIVE) {
+      continue;
+    }
+    QuicTime path_retransmission_time =
+        path_manager_info.manager->GetRetransmissionTime();
+    if (!path_retransmission_time.IsInitialized()) {
+      continue;
+    }
+    if (!retransmission_time.IsInitialized() ||
+        path_retransmission_time < retransmission_time) {
+      retransmission_time = path_retransmission_time;
+    }
+  }
+
+  return retransmission_time;
+}
+
+const RttStats* QuicMultipathSentPacketManager::GetRttStats() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return nullptr;
+  }
+  return path_manager->GetRttStats();
+}
+
+QuicBandwidth QuicMultipathSentPacketManager::BandwidthEstimate() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return QuicBandwidth::Zero();
+  }
+  return path_manager->BandwidthEstimate();
+}
+
+const QuicSustainedBandwidthRecorder*
+QuicMultipathSentPacketManager::SustainedBandwidthRecorder() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return nullptr;
+  }
+  return path_manager->SustainedBandwidthRecorder();
+}
+
+QuicPacketCount QuicMultipathSentPacketManager::GetCongestionWindowInTcpMss()
+    const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetCongestionWindowInTcpMss();
+}
+
+QuicPacketCount QuicMultipathSentPacketManager::EstimateMaxPacketsInFlight(
+    QuicByteCount max_packet_length) const {
+  QuicPacketCount max_packets_in_flight = 0;
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager != nullptr) {
+      max_packets_in_flight =
+          max(max_packets_in_flight,
+              path_manager_info.manager->EstimateMaxPacketsInFlight(
+                  max_packet_length));
+    }
+  }
+  DCHECK_LT(0u, max_packets_in_flight);
+  return max_packets_in_flight;
+}
+
+QuicByteCount QuicMultipathSentPacketManager::GetCongestionWindowInBytes()
+    const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetCongestionWindowInBytes();
+}
+
+QuicPacketCount QuicMultipathSentPacketManager::GetSlowStartThresholdInTcpMss()
+    const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetSlowStartThresholdInTcpMss();
+}
+
+void QuicMultipathSentPacketManager::CancelRetransmissionsForStream(
+    QuicStreamId stream_id) {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager != nullptr) {
+      path_manager_info.manager->CancelRetransmissionsForStream(stream_id);
+    }
+  }
+}
+
+void QuicMultipathSentPacketManager::OnConnectionMigration(
+    QuicPathId path_id,
+    PeerAddressChangeType type) {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(path_id);
+  if (path_manager == nullptr) {
+    OnUnrecoverablePathError(path_id);
+    return;
+  }
+  path_manager->OnConnectionMigration(path_id, type);
+}
+
+bool QuicMultipathSentPacketManager::IsHandshakeConfirmed() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  return path_manager != nullptr && path_manager->IsHandshakeConfirmed();
+}
+
+void QuicMultipathSentPacketManager::SetDebugDelegate(
+    DebugDelegate* debug_delegate) {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager == nullptr) {
+      continue;
+    }
+    path_manager_info.manager->SetDebugDelegate(debug_delegate);
+  }
+}
+
+QuicPacketNumber QuicMultipathSentPacketManager::GetLargestObserved(
+    QuicPathId path_id) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetLargestObserved(path_id);
+}
+
+QuicPacketNumber QuicMultipathSentPacketManager::GetLargestSentPacket(
+    QuicPathId path_id) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetLargestSentPacket(path_id);
+}
+
+QuicPacketNumber QuicMultipathSentPacketManager::GetLeastPacketAwaitedByPeer(
+    QuicPathId path_id) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetLeastPacketAwaitedByPeer(path_id);
+}
+
+void QuicMultipathSentPacketManager::SetNetworkChangeVisitor(
+    NetworkChangeVisitor* visitor) {
+  for (PathSentPacketManagerInfo path_manager_info : path_managers_info_) {
+    if (path_manager_info.manager == nullptr ||
+        path_manager_info.state != ACTIVE) {
+      continue;
+    }
+    path_manager_info.manager->SetNetworkChangeVisitor(visitor);
+  }
+}
+
+bool QuicMultipathSentPacketManager::InSlowStart() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  return path_manager != nullptr && path_manager->InSlowStart();
+}
+
+size_t QuicMultipathSentPacketManager::GetConsecutiveRtoCount() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetConsecutiveRtoCount();
+}
+size_t QuicMultipathSentPacketManager::GetConsecutiveTlpCount() const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForActivePath(kDefaultPathId);
+  if (path_manager == nullptr) {
+    return 0;
+  }
+  return path_manager->GetConsecutiveTlpCount();
+}
+
+QuicMultipathSentPacketManager::PathSentPacketManagerInfo::
+    PathSentPacketManagerInfo()
+    : manager(nullptr), state(CLOSING) {}
+
+QuicMultipathSentPacketManager::PathSentPacketManagerInfo::
+    PathSentPacketManagerInfo(QuicSentPacketManagerInterface* manager,
+                              PathSentPacketManagerState state)
+    : manager(manager), state(state) {}
+
+QuicMultipathSentPacketManager::PathSentPacketManagerInfo::
+    PathSentPacketManagerInfo(const PathSentPacketManagerInfo& other) = default;
+
+QuicSentPacketManagerInterface*
+QuicMultipathSentPacketManager::MaybeGetSentPacketManagerForPath(
+    QuicPathId path_id) const {
+  if (path_id >= path_managers_info_.size() ||
+      path_managers_info_[path_id].manager == nullptr) {
+    QUIC_BUG << "Sent packet manager of path: ("
+             << base::IntToString(path_id)
+             << ") must exist but does not.";
+    return nullptr;
+  }
+
+  return path_managers_info_[path_id].manager;
+}
+
+QuicSentPacketManagerInterface*
+QuicMultipathSentPacketManager::MaybeGetSentPacketManagerForActivePath(
+    QuicPathId path_id) const {
+  QuicSentPacketManagerInterface* path_manager =
+      MaybeGetSentPacketManagerForPath(path_id);
+  if (path_manager == nullptr) {
+    return nullptr;
+  }
+  if (path_managers_info_[path_id].state != ACTIVE) {
+    QUIC_BUG << "Sent packet manager of path: ("
+             << base::IntToString(path_id)
+             << ") must be active but is not.";
+    return nullptr;
+  }
+
+  return path_manager;
+}
+
+QuicPathId QuicMultipathSentPacketManager::DetermineRetransmissionTimeoutPath()
+    const {
+  QuicTime retransmission_time = QuicTime::Zero();
+  QuicPathId rto_path = kInvalidPathId;
+  for (size_t i = 0; i < path_managers_info_.size(); ++i) {
+    if (path_managers_info_[i].manager == nullptr ||
+        path_managers_info_[i].state != ACTIVE) {
+      continue;
+    }
+    QuicTime path_retransmission_time =
+        path_managers_info_[i].manager->GetRetransmissionTime();
+    if (!path_retransmission_time.IsInitialized()) {
+      continue;
+    }
+    if (!retransmission_time.IsInitialized() ||
+        path_retransmission_time < retransmission_time) {
+      retransmission_time = path_retransmission_time;
+      rto_path = i;
+    }
+  }
+  return rto_path;
+}
+
+void QuicMultipathSentPacketManager::OnUnrecoverablePathError(
+    QuicPathId path_id) {
+  if (MaybeGetSentPacketManagerForPath(path_id) == nullptr) {
+    const string error_details =
+        "Sent packet manager of path: (" + base::IntToString(path_id) +
+        ") must exist but does not.";
+    delegate_->OnUnrecoverableError(QUIC_MULTIPATH_PATH_DOES_NOT_EXIST,
+                                    error_details,
+                                    ConnectionCloseSource::FROM_SELF);
+    return;
+  }
+  const string error_details =
+      "Sent packet manager of path: (" + base::IntToString(path_id) +
+      ") must be active but is not.";
+  delegate_->OnUnrecoverableError(QUIC_MULTIPATH_PATH_NOT_ACTIVE, error_details,
+                                  ConnectionCloseSource::FROM_SELF);
+}
+
+}  // namespace net