Add missing third_party/quic_trace/src files

These files got omitted because there was a stray .gitmodules file in
the directory which put git into a weird limbo state where it had no
_normal_ record (.gitmodules, .git/config, .git/modules) of that
directory being a module, but it also ignored any files put there.

TBR=mfoltz@chromium.org

Change-Id: I1d46db197e8dc9f0f01f02fbc5a4cc5f02f04eda
diff --git a/third_party/quic_trace/src b/third_party/quic_trace/src
deleted file mode 160000
index c902890..0000000
--- a/third_party/quic_trace/src
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit c9028909ba2356e073de4ea963b56fd81417a46d
diff --git a/third_party/quic_trace/src/CONTRIBUTING.md b/third_party/quic_trace/src/CONTRIBUTING.md
new file mode 100644
index 0000000..939e534
--- /dev/null
+++ b/third_party/quic_trace/src/CONTRIBUTING.md
@@ -0,0 +1,28 @@
+# How to Contribute
+
+We'd love to accept your patches and contributions to this project. There are
+just a few small guidelines you need to follow.
+
+## Contributor License Agreement
+
+Contributions to this project must be accompanied by a Contributor License
+Agreement. You (or your employer) retain the copyright to your contribution;
+this simply gives us permission to use and redistribute your contributions as
+part of the project. Head over to <https://cla.developers.google.com/> to see
+your current agreements on file or to sign a new one.
+
+You generally only need to submit a CLA once, so if you've already submitted one
+(even if it was for a different project), you probably don't need to do it
+again.
+
+## Code reviews
+
+All submissions, including submissions by project members, require review. We
+use GitHub pull requests for this purpose. Consult
+[GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
+information on using pull requests.
+
+## Community Guidelines
+
+This project follows [Google's Open Source Community
+Guidelines](https://opensource.google.com/conduct/).
diff --git a/third_party/quic_trace/src/LICENSE b/third_party/quic_trace/src/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/third_party/quic_trace/src/LICENSE
@@ -0,0 +1,202 @@
+
+                                 Apache License
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+      the terms of any separate license agreement you may have executed
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+   Unless required by applicable law or agreed to in writing, software
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diff --git a/third_party/quic_trace/src/README.md b/third_party/quic_trace/src/README.md
new file mode 100644
index 0000000..8fce490
--- /dev/null
+++ b/third_party/quic_trace/src/README.md
@@ -0,0 +1,26 @@
+# QUIC trace utilities
+
+This repository contains a format for recording a trace of QUIC connection,
+together with the tools for analyzing the resulting traces.  This format of
+traces is currently partially supported by Chromium, and we hope for more
+implementations to adopt it in the future.
+
+The primary focus of this format is debugging congestion-control related
+issues, but other transport aspects (e.g. flow control) and transport-related
+aspects of the application (e.g. annotations for the types of data carried by
+the streams) are also within the scope.
+
+## How to record this format
+
+The traces are represented as a Protocol Buffer, which is completely described
+in `lib/quic_trace.proto`.  Projects that use Bazel can embed this repository
+directly and use the provided Bazel rules.
+
+## How to render the resulting trace
+
+Currently, we only support a simple visualization that uses gnuplot.
+
+1. Build the helper tool by running `bazel build
+   //tools/quic_trace_to_time_sequence_gnuplot`.
+1. Generate the graph by running `tools/time_sequence_gnuplot.sh trace_file
+   trace.png`.
diff --git a/third_party/quic_trace/src/WORKSPACE b/third_party/quic_trace/src/WORKSPACE
new file mode 100644
index 0000000..a4a632f
--- /dev/null
+++ b/third_party/quic_trace/src/WORKSPACE
@@ -0,0 +1,20 @@
+workspace(name = "com_google_quic_trace")
+
+http_archive(
+    name = "com_google_protobuf",
+    sha256 = "1b666f3990f66890ade9faa77d134f0369c19d3721dc8111643b56685a717319",
+    strip_prefix = "protobuf-3.5.1",
+    urls = ["https://github.com/google/protobuf/releases/download/v3.5.1/protobuf-all-3.5.1.zip"],
+)
+
+http_archive(
+    name = "com_github_gflags_gflags",
+    sha256 = "4e44b69e709c826734dbbbd5208f61888a2faf63f239d73d8ba0011b2dccc97a",
+    strip_prefix = "gflags-2.2.1",
+    urls = ["https://github.com/gflags/gflags/archive/v2.2.1.zip"],
+)
+
+bind(
+    name = "gflags",
+    actual = "@com_github_gflags_gflags//:gflags",
+)
diff --git a/third_party/quic_trace/src/lib/BUILD b/third_party/quic_trace/src/lib/BUILD
new file mode 100644
index 0000000..d2b47e1
--- /dev/null
+++ b/third_party/quic_trace/src/lib/BUILD
@@ -0,0 +1,27 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+licenses(["notice"])  # Apache 2.0
+
+proto_library(
+    name = "quic_trace_proto",
+    srcs = ["quic_trace.proto"],
+    visibility = ["//visibility:public"],
+)
+
+cc_proto_library(
+    name = "quic_trace_cc_proto",
+    visibility = ["//visibility:public"],
+    deps = [":quic_trace_proto"],
+)
diff --git a/third_party/quic_trace/src/lib/quic_trace.proto b/third_party/quic_trace/src/lib/quic_trace.proto
new file mode 100644
index 0000000..a13f9b3
--- /dev/null
+++ b/third_party/quic_trace/src/lib/quic_trace.proto
@@ -0,0 +1,143 @@
+// Copyright 2018 Google LLC
+// 
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// 
+//     https://www.apache.org/licenses/LICENSE-2.0
+// 
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto2";
+
+package quic_trace;
+
+enum FrameType {
+  UNKNOWN_FRAME = 0;
+
+  STREAM = 1;
+  ACK = 2;
+  RESET_STREAM = 3;
+  CONNECTION_CLOSE = 4;
+  MAX_DATA = 5;
+  MAX_STREAM_DATA = 6;
+  PING = 7;
+  BLOCKED = 8;
+  STREAM_BLOCKED = 9;
+  PADDING = 10;
+};
+
+// Metadata for STREAM frames.
+message StreamFrameInfo {
+  optional uint64 stream_id = 1;
+  optional bool fin = 2;
+  optional uint64 length = 3;
+  optional uint64 offset = 4;
+};
+
+// The intervals are closed, i.e. the interval represented here is
+// [first_packet, last_packet].
+message AckBlock {
+  optional uint64 first_packet = 1;
+  optional uint64 last_packet = 2;
+};
+
+// Metadata for ACK frames.
+message AckInfo {
+  repeated AckBlock acked_packets = 1;
+  optional uint64 ack_delay_us = 2;
+};
+
+// Metadata for RST_STREAM frames.
+message ResetStreamInfo {
+  optional uint64 stream_id = 1;
+  optional uint32 application_error_code = 2;
+  optional uint64 final_offset = 3;
+};
+
+// Metadata for CONNECTION_CLOSE/APPLICATION_CLOSE frames.
+message CloseInfo {
+  optional uint32 error_code = 1;
+  optional string reason_phrase = 2;
+};
+
+// Metadata for MAX_DATA/MAX_STREAM_DATA frames.
+message FlowControlInfo {
+  optional uint64 max_data = 1;
+  optional uint64 stream_id = 2;
+};
+
+// A message representing a frame, either sent or received.
+message Frame {
+  optional FrameType frame_type = 1;
+
+  optional StreamFrameInfo stream_frame_info = 2;
+  optional AckInfo ack_info = 3;
+  optional ResetStreamInfo reset_stream_info = 4;
+  optional CloseInfo close_info = 5;
+  optional FlowControlInfo flow_control_info = 6;
+};
+
+// Metadata that represents transport stack's understanding of the current state
+// of the transport channel.
+message TransportState {
+  optional uint64 min_rtt_us = 1;
+  // Smoothed RTT, usually computed using EWMA.
+  optional uint64 smoothed_rtt_us = 2;
+  // The latest RTT measureent available.
+  optional uint64 last_rtt_us = 3;
+
+  optional uint64 in_flight_bytes = 4;
+  optional uint64 cwnd_bytes = 5;
+  // Pacing rate, in bits per second.
+  optional uint64 pacing_rate_bps = 6;
+
+  // Any arbitrary information about congestion control state that is not
+  // representable via parameters above.
+  optional string congestion_control_state = 7;
+};
+
+enum EncryptionLevel {
+  ENCRYPTION_UNKNOWN = 0;
+
+  ENCRYPTION_INITIAL = 1;
+  ENCRYPTION_0RTT = 2;
+  ENCRYPTION_1RTT = 3;
+};
+
+enum EventType {
+  UNKNOWN_EVENT = 0;
+
+  PACKET_SENT = 1;
+  PACKET_RECEIVED = 2;
+  PACKET_LOST = 3;
+};
+
+// An event that has occurred over duration of the connection.
+message Event {
+  optional uint64 time_us = 1;
+  optional EventType event_type = 2;
+
+  optional uint64 packet_number = 3;
+  repeated Frame frames = 4;
+  optional uint64 packet_size = 5;
+  optional EncryptionLevel encryption_level = 6;
+  // State of the transport stack after the event has happened.
+  optional TransportState transport_state = 7;
+};
+
+message Trace {
+  // QUIC version tag, as represented on wire.  Should be always 4 bytes long.
+  optional bytes protocol_version = 1;
+
+  // Source and destination connection ID.  If multiple connection IDs are used,
+  // record the first one used with short-form header.
+  optional bytes source_connection_id = 2;
+  optional bytes destination_connection_id = 3;
+
+  repeated Event events = 4;
+};
diff --git a/third_party/quic_trace/src/tools/BUILD b/third_party/quic_trace/src/tools/BUILD
new file mode 100644
index 0000000..78bed69
--- /dev/null
+++ b/third_party/quic_trace/src/tools/BUILD
@@ -0,0 +1,30 @@
+# Copyright 2018 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+licenses(["notice"])  # Apache 2.0
+
+cc_binary(
+    name = "quic_trace_to_time_sequence_gnuplot",
+    srcs = ["quic_trace_to_time_sequence_gnuplot.cc"],
+    deps = [
+        "//external:gflags",
+        "//lib:quic_trace_cc_proto",
+    ],
+)
+
+sh_binary(
+    name = "time_sequence_gnuplot",
+    srcs = ["time_sequence_gnuplot.sh"],
+    data = [":quic_trace_to_time_sequence_gnuplot"],
+)
diff --git a/third_party/quic_trace/src/tools/quic_trace_to_time_sequence_gnuplot.cc b/third_party/quic_trace/src/tools/quic_trace_to_time_sequence_gnuplot.cc
new file mode 100644
index 0000000..76d5279
--- /dev/null
+++ b/third_party/quic_trace/src/tools/quic_trace_to_time_sequence_gnuplot.cc
@@ -0,0 +1,143 @@
+// Copyright 2018 Google LLC
+// 
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// 
+//     https://www.apache.org/licenses/LICENSE-2.0
+// 
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Helper script to generate time sequence plot using gnuplot.
+// Accepts the trace on stdin, and outputs the gnuplot-consumable time series
+// file into stdout.
+
+#include <iostream>
+
+#include "gflags/gflags.h"
+#include "lib/quic_trace.pb.h"
+
+DEFINE_string(sequence, "Which time sequence to plot: send, ack or loss.", "");
+DEFINE_bool(filter_old_acks,
+            true,
+            "Do not show an ack for a packet if it was already previously "
+            "acknowledged");
+
+namespace quic_trace {
+namespace {
+
+// Calculates the amount of actual data in the packet.
+size_t FrameDataInSentPacket(const Event& packet) {
+  if (packet.event_type() != PACKET_SENT) {
+    return 0;
+  }
+
+  size_t sent_in_packet = 0;
+  for (const Frame& frame : packet.frames()) {
+    if (frame.frame_type() != STREAM || !frame.has_stream_frame_info()) {
+      continue;
+    }
+    sent_in_packet += frame.stream_frame_info().length();
+  }
+  return sent_in_packet;
+}
+
+struct SentPacket {
+  // Offset of the stream data sent in the frame with respect to the beginning
+  // of the connection.
+  size_t offset;
+  // Size of frame data in the packet.
+  size_t size;
+};
+// Map of the sent packets, keyed by packet number.
+using SentPacketMap = std::unordered_map<uint64_t, SentPacket>;
+
+void PrintSentPacket(const SentPacketMap& packet_map,
+                     uint64_t packet_number,
+                     uint64_t time) {
+  auto original_packet_it = packet_map.find(packet_number);
+  if (original_packet_it == packet_map.end()) {
+    return;
+  }
+
+  const SentPacket& original_packet = original_packet_it->second;
+
+  std::cout << time << " " << original_packet.offset << std::endl;
+  std::cout << time << " " << (original_packet.offset + original_packet.size)
+            << std::endl;
+  std::cout << std::endl;
+}
+
+void PrintTimeSequence(std::istream* trace_source) {
+  Trace trace;
+  trace.ParseFromIstream(trace_source);
+
+  size_t total_sent = 0;
+  SentPacketMap packet_map;
+  std::unordered_set<uint64_t> already_acknowledged;
+  // In a single pass, compute |packet_map| and output the requested sequence.
+  for (const Event& event : trace.events()) {
+    // Track all sent packets and their offsets in the plot.
+    size_t sent_in_packet = FrameDataInSentPacket(event);
+    if (sent_in_packet != 0) {
+      packet_map.emplace(event.packet_number(),
+                         SentPacket{total_sent, sent_in_packet});
+    }
+    total_sent += sent_in_packet;
+
+    // Output sent packets.
+    if (sent_in_packet != 0 && FLAGS_sequence == "send") {
+      std::cout << event.time_us() << " " << (total_sent - sent_in_packet)
+                << std::endl;
+      std::cout << event.time_us() << " " << total_sent << std::endl;
+      std::cout << std::endl;
+    }
+
+    // Output loss events.
+    if (event.event_type() == PACKET_LOST && FLAGS_sequence == "loss") {
+      PrintSentPacket(packet_map, event.packet_number(), event.time_us());
+    }
+
+    // Output acks.
+    if (event.event_type() == PACKET_RECEIVED) {
+      for (const Frame& frame : event.frames()) {
+        if (frame.frame_type() == ACK && FLAGS_sequence == "ack") {
+          for (const AckBlock& block : frame.ack_info().acked_packets()) {
+            for (uint64_t packet = block.first_packet();
+                 packet <= block.last_packet(); packet++) {
+              if (FLAGS_filter_old_acks) {
+                if (already_acknowledged.count(packet) > 0) {
+                  continue;
+                }
+                already_acknowledged.insert(packet);
+              }
+              PrintSentPacket(packet_map, packet, event.time_us());
+            }
+          }
+        }
+      }
+    }
+  }
+}
+
+}  // namespace
+}  // namespace quic_trace
+
+int main(int argc, char* argv[]) {
+  gflags::ParseCommandLineFlags(&argc, &argv, true);
+
+  if (FLAGS_sequence != "send" && FLAGS_sequence != "ack" &&
+      FLAGS_sequence != "loss") {
+    std::cerr << "The --type parameter has to be set to either 'send', 'ack' "
+                 "or 'loss'."
+              << std::endl;
+    return 1;
+  }
+
+  quic_trace::PrintTimeSequence(&std::cin);
+  return 0;
+}
diff --git a/third_party/quic_trace/src/tools/time_sequence_gnuplot.sh b/third_party/quic_trace/src/tools/time_sequence_gnuplot.sh
new file mode 100755
index 0000000..da9302f
--- /dev/null
+++ b/third_party/quic_trace/src/tools/time_sequence_gnuplot.sh
@@ -0,0 +1,67 @@
+#!/bin/bash
+
+# Copyright 2018 Google LLC
+# 
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#     https://www.apache.org/licenses/LICENSE-2.0
+# 
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+#
+# Render a trace using gnuplot into a png file.
+#
+
+if [ -z "$1" ]; then
+  echo "Usage: time_sequence_gnuplot.sh path/to/trace output.png"
+  exit 1
+fi
+
+if [ ! -f "$1" ]; then
+  echo "File $1 does not exist or is not a file"
+  exit 1
+fi
+
+if [ -z "$2" ]; then
+  echo "Output file not specified"
+  exit 1
+fi
+
+if [ ! -x "$QUIC_TRACE_CONV_BIN" ]; then
+  QUIC_TRACE_CONV_BIN="$0.runfiles/com_google_quic_trace/tools/quic_trace_to_time_sequence_gnuplot"
+fi
+
+if [ ! -x "$QUIC_TRACE_CONV_BIN" ]; then
+  echo "Cannot find conversion tool binary"
+  exit 1
+fi
+
+TMPDIR="$(mktemp -d)"
+for event_type in send ack loss; do
+  "$QUIC_TRACE_CONV_BIN" --sequence=$event_type < "$1" > "$TMPDIR/$event_type.txt"
+done
+
+if [ -z "$GNUPLOT_SIZE" ]; then
+  GNUPLOT_SIZE="7680,4320"
+fi
+if [ -z "$GNUPLOT_TERMINAL" ]; then
+  GNUPLOT_TERMINAL="png size $GNUPLOT_SIZE"
+fi
+
+
+gnuplot <<EOF
+set terminal $GNUPLOT_TERMINAL
+set output "$2"
+plot \
+   "$TMPDIR/send.txt" with lines lt rgb "blue" title "Sent", \
+   "$TMPDIR/ack.txt" with lines lt rgb "green" title "Ack", \
+   "$TMPDIR/loss.txt" with lines lt rgb "red" title "Loss"
+EOF
+
+rm -rf "$TMPDIR"