src/net/quic/core/quic_data_writer_test.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/core/quic_data_writer.h"

#include <cstdint>

#include "net/quic/core/quic_data_reader.h"
#include "net/quic/core/quic_utils.h"
#include "net/quic/platform/api/quic_flags.h"
#include "net/quic/platform/api/quic_test.h"
#include "net/quic/test_tools/quic_test_utils.h"

namespace net {
namespace test {
namespace {

char* AsChars(unsigned char* data) {
  return reinterpret_cast<char*>(data);
}

struct TestParams {
  TestParams(Perspective perspective, Endianness endianness)
      : perspective(perspective), endianness(endianness) {}

  Perspective perspective;
  Endianness endianness;
};

std::vector<TestParams> GetTestParams() {
  std::vector<TestParams> params;
  for (Perspective perspective :
       {Perspective::IS_CLIENT, Perspective::IS_SERVER}) {
    for (Endianness endianness : {NETWORK_BYTE_ORDER, HOST_BYTE_ORDER}) {
      params.push_back(TestParams(perspective, endianness));
    }
  }
  return params;
}

class QuicDataWriterTest : public QuicTestWithParam<TestParams> {};

INSTANTIATE_TEST_CASE_P(QuicDataWriterTests,
                        QuicDataWriterTest,
                        ::testing::ValuesIn(GetTestParams()));

TEST_P(QuicDataWriterTest, SanityCheckUFloat16Consts) {
  // Check the arithmetic on the constants - otherwise the values below make
  // no sense.
  EXPECT_EQ(30, kUFloat16MaxExponent);
  EXPECT_EQ(11, kUFloat16MantissaBits);
  EXPECT_EQ(12, kUFloat16MantissaEffectiveBits);
  EXPECT_EQ(UINT64_C(0x3FFC0000000), kUFloat16MaxValue);
}

TEST_P(QuicDataWriterTest, WriteUFloat16) {
  struct TestCase {
    uint64_t decoded;
    uint16_t encoded;
  };
  TestCase test_cases[] = {
      // Small numbers represent themselves.
      {0, 0},
      {1, 1},
      {2, 2},
      {3, 3},
      {4, 4},
      {5, 5},
      {6, 6},
      {7, 7},
      {15, 15},
      {31, 31},
      {42, 42},
      {123, 123},
      {1234, 1234},
      // Check transition through 2^11.
      {2046, 2046},
      {2047, 2047},
      {2048, 2048},
      {2049, 2049},
      // Running out of mantissa at 2^12.
      {4094, 4094},
      {4095, 4095},
      {4096, 4096},
      {4097, 4096},
      {4098, 4097},
      {4099, 4097},
      {4100, 4098},
      {4101, 4098},
      // Check transition through 2^13.
      {8190, 6143},
      {8191, 6143},
      {8192, 6144},
      {8193, 6144},
      {8194, 6144},
      {8195, 6144},
      {8196, 6145},
      {8197, 6145},
      // Half-way through the exponents.
      {0x7FF8000, 0x87FF},
      {0x7FFFFFF, 0x87FF},
      {0x8000000, 0x8800},
      {0xFFF0000, 0x8FFF},
      {0xFFFFFFF, 0x8FFF},
      {0x10000000, 0x9000},
      // Transition into the largest exponent.
      {0x1FFFFFFFFFE, 0xF7FF},
      {0x1FFFFFFFFFF, 0xF7FF},
      {0x20000000000, 0xF800},
      {0x20000000001, 0xF800},
      {0x2003FFFFFFE, 0xF800},
      {0x2003FFFFFFF, 0xF800},
      {0x20040000000, 0xF801},
      {0x20040000001, 0xF801},
      // Transition into the max value and clamping.
      {0x3FF80000000, 0xFFFE},
      {0x3FFBFFFFFFF, 0xFFFE},
      {0x3FFC0000000, 0xFFFF},
      {0x3FFC0000001, 0xFFFF},
      {0x3FFFFFFFFFF, 0xFFFF},
      {0x40000000000, 0xFFFF},
      {0xFFFFFFFFFFFFFFFF, 0xFFFF},
  };
  int num_test_cases = sizeof(test_cases) / sizeof(test_cases[0]);

  for (int i = 0; i < num_test_cases; ++i) {
    char buffer[2];
    QuicDataWriter writer(2, buffer, GetParam().perspective,
                          GetParam().endianness);
    EXPECT_TRUE(writer.WriteUFloat16(test_cases[i].decoded));
    uint16_t result = *reinterpret_cast<uint16_t*>(writer.data());
    if (GetParam().endianness == NETWORK_BYTE_ORDER) {
      result = QuicEndian::HostToNet16(result);
    }
    EXPECT_EQ(test_cases[i].encoded, result);
  }
}

TEST_P(QuicDataWriterTest, ReadUFloat16) {
  struct TestCase {
    uint64_t decoded;
    uint16_t encoded;
  };
  TestCase test_cases[] = {
      // There are fewer decoding test cases because encoding truncates, and
      // decoding returns the smallest expansion.
      // Small numbers represent themselves.
      {0, 0},
      {1, 1},
      {2, 2},
      {3, 3},
      {4, 4},
      {5, 5},
      {6, 6},
      {7, 7},
      {15, 15},
      {31, 31},
      {42, 42},
      {123, 123},
      {1234, 1234},
      // Check transition through 2^11.
      {2046, 2046},
      {2047, 2047},
      {2048, 2048},
      {2049, 2049},
      // Running out of mantissa at 2^12.
      {4094, 4094},
      {4095, 4095},
      {4096, 4096},
      {4098, 4097},
      {4100, 4098},
      // Check transition through 2^13.
      {8190, 6143},
      {8192, 6144},
      {8196, 6145},
      // Half-way through the exponents.
      {0x7FF8000, 0x87FF},
      {0x8000000, 0x8800},
      {0xFFF0000, 0x8FFF},
      {0x10000000, 0x9000},
      // Transition into the largest exponent.
      {0x1FFE0000000, 0xF7FF},
      {0x20000000000, 0xF800},
      {0x20040000000, 0xF801},
      // Transition into the max value.
      {0x3FF80000000, 0xFFFE},
      {0x3FFC0000000, 0xFFFF},
  };
  int num_test_cases = sizeof(test_cases) / sizeof(test_cases[0]);

  for (int i = 0; i < num_test_cases; ++i) {
    uint16_t encoded_ufloat = test_cases[i].encoded;
    if (GetParam().endianness == NETWORK_BYTE_ORDER) {
      encoded_ufloat = QuicEndian::HostToNet16(encoded_ufloat);
    }
    QuicDataReader reader(reinterpret_cast<char*>(&encoded_ufloat), 2,
                          GetParam().perspective, GetParam().endianness);
    uint64_t value;
    EXPECT_TRUE(reader.ReadUFloat16(&value));
    EXPECT_EQ(test_cases[i].decoded, value);
  }
}

TEST_P(QuicDataWriterTest, RoundTripUFloat16) {
  // Just test all 16-bit encoded values. 0 and max already tested above.
  uint64_t previous_value = 0;
  for (uint16_t i = 1; i < 0xFFFF; ++i) {
    // Read the two bytes.
    uint16_t read_number = i;
    if (GetParam().endianness == NETWORK_BYTE_ORDER) {
      read_number = QuicEndian::HostToNet16(read_number);
    }
    QuicDataReader reader(reinterpret_cast<char*>(&read_number), 2,
                          GetParam().perspective, GetParam().endianness);
    uint64_t value;
    // All values must be decodable.
    EXPECT_TRUE(reader.ReadUFloat16(&value));
    // Check that small numbers represent themselves
    if (i < 4097) {
      EXPECT_EQ(i, value);
    }
    // Check there's monotonic growth.
    EXPECT_LT(previous_value, value);
    // Check that precision is within 0.5% away from the denormals.
    if (i > 2000) {
      EXPECT_GT(previous_value * 1005, value * 1000);
    }
    // Check we're always within the promised range.
    EXPECT_LT(value, UINT64_C(0x3FFC0000000));
    previous_value = value;
    char buffer[6];
    QuicDataWriter writer(6, buffer, GetParam().perspective,
                          GetParam().endianness);
    EXPECT_TRUE(writer.WriteUFloat16(value - 1));
    EXPECT_TRUE(writer.WriteUFloat16(value));
    EXPECT_TRUE(writer.WriteUFloat16(value + 1));
    // Check minimal decoding (previous decoding has previous encoding).
    uint16_t encoded1 = *reinterpret_cast<uint16_t*>(writer.data());
    uint16_t encoded2 = *reinterpret_cast<uint16_t*>(writer.data() + 2);
    uint16_t encoded3 = *reinterpret_cast<uint16_t*>(writer.data() + 4);
    if (GetParam().endianness == NETWORK_BYTE_ORDER) {
      encoded1 = QuicEndian::NetToHost16(encoded1);
      encoded2 = QuicEndian::NetToHost16(encoded2);
      encoded3 = QuicEndian::NetToHost16(encoded3);
    }
    EXPECT_EQ(i - 1, encoded1);
    // Check roundtrip.
    EXPECT_EQ(i, encoded2);
    // Check next decoding.
    EXPECT_EQ(i < 4096 ? i + 1 : i, encoded3);
  }
}

TEST_P(QuicDataWriterTest, WriteConnectionId) {
  uint64_t connection_id = 0x0011223344556677;
  char big_endian[] = {
      0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
  };
  const int kBufferLength = sizeof(connection_id);
  char buffer[kBufferLength];
  QuicDataWriter writer(kBufferLength, buffer, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteConnectionId(connection_id);
  test::CompareCharArraysWithHexError("connection_id", buffer, kBufferLength,
                                      big_endian, kBufferLength);

  uint64_t read_connection_id;
  QuicDataReader reader(buffer, kBufferLength, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadConnectionId(&read_connection_id);
  EXPECT_EQ(connection_id, read_connection_id);
}

TEST_P(QuicDataWriterTest, WriteTag) {
  char CHLO[] = {
      'C', 'H', 'L', 'O',
  };
  const int kBufferLength = sizeof(QuicTag);
  char buffer[kBufferLength];
  QuicDataWriter writer(kBufferLength, buffer, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteTag(kCHLO);
  test::CompareCharArraysWithHexError("CHLO", buffer, kBufferLength, CHLO,
                                      kBufferLength);

  QuicTag read_chlo;
  QuicDataReader reader(buffer, kBufferLength, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadTag(&read_chlo);
  EXPECT_EQ(kCHLO, read_chlo);
}

TEST_P(QuicDataWriterTest, Write16BitUnsignedIntegers) {
  char little_endian16[] = {0x22, 0x11};
  char big_endian16[] = {0x11, 0x22};
  char buffer16[2];
  {
    uint16_t in_memory16 = 0x1122;
    QuicDataWriter writer(2, buffer16, GetParam().perspective,
                          GetParam().endianness);
    writer.WriteUInt16(in_memory16);
    test::CompareCharArraysWithHexError(
        "uint16_t", buffer16, 2,
        GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian16
                                                    : little_endian16,
        2);

    uint16_t read_number16;
    QuicDataReader reader(buffer16, 2, GetParam().perspective,
                          GetParam().endianness);
    reader.ReadUInt16(&read_number16);
    EXPECT_EQ(in_memory16, read_number16);
  }

  {
    uint64_t in_memory16 = 0x0000000000001122;
    QuicDataWriter writer(2, buffer16, GetParam().perspective,
                          GetParam().endianness);
    writer.WriteBytesToUInt64(2, in_memory16);
    test::CompareCharArraysWithHexError(
        "uint16_t", buffer16, 2,
        GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian16
                                                    : little_endian16,
        2);

    uint64_t read_number16 = 0u;
    QuicDataReader reader(buffer16, 2, GetParam().perspective,
                          GetParam().endianness);
    reader.ReadBytesToUInt64(2, &read_number16);
    EXPECT_EQ(in_memory16, read_number16);
  }
}

TEST_P(QuicDataWriterTest, Write24BitUnsignedIntegers) {
  char little_endian24[] = {0x33, 0x22, 0x11};
  char big_endian24[] = {0x11, 0x22, 0x33};
  char buffer24[3];
  uint64_t in_memory24 = 0x0000000000112233;
  QuicDataWriter writer(3, buffer24, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteBytesToUInt64(3, in_memory24);
  test::CompareCharArraysWithHexError(
      "uint24", buffer24, 3,
      GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian24
                                                  : little_endian24,
      3);

  uint64_t read_number24 = 0u;
  QuicDataReader reader(buffer24, 3, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadBytesToUInt64(3, &read_number24);
  EXPECT_EQ(in_memory24, read_number24);
}

TEST_P(QuicDataWriterTest, Write32BitUnsignedIntegers) {
  char little_endian32[] = {0x44, 0x33, 0x22, 0x11};
  char big_endian32[] = {0x11, 0x22, 0x33, 0x44};
  char buffer32[4];
  {
    uint32_t in_memory32 = 0x11223344;
    QuicDataWriter writer(4, buffer32, GetParam().perspective,
                          GetParam().endianness);
    writer.WriteUInt32(in_memory32);
    test::CompareCharArraysWithHexError(
        "uint32_t", buffer32, 4,
        GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian32
                                                    : little_endian32,
        4);

    uint32_t read_number32;
    QuicDataReader reader(buffer32, 4, GetParam().perspective,
                          GetParam().endianness);
    reader.ReadUInt32(&read_number32);
    EXPECT_EQ(in_memory32, read_number32);
  }

  {
    uint64_t in_memory32 = 0x11223344;
    QuicDataWriter writer(4, buffer32, GetParam().perspective,
                          GetParam().endianness);
    writer.WriteBytesToUInt64(4, in_memory32);
    test::CompareCharArraysWithHexError(
        "uint32_t", buffer32, 4,
        GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian32
                                                    : little_endian32,
        4);

    uint64_t read_number32 = 0u;
    QuicDataReader reader(buffer32, 4, GetParam().perspective,
                          GetParam().endianness);
    reader.ReadBytesToUInt64(4, &read_number32);
    EXPECT_EQ(in_memory32, read_number32);
  }
}

TEST_P(QuicDataWriterTest, Write40BitUnsignedIntegers) {
  uint64_t in_memory40 = 0x0000001122334455;
  char little_endian40[] = {0x55, 0x44, 0x33, 0x22, 0x11};
  char big_endian40[] = {0x11, 0x22, 0x33, 0x44, 0x55};
  char buffer40[5];
  QuicDataWriter writer(5, buffer40, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteBytesToUInt64(5, in_memory40);
  test::CompareCharArraysWithHexError(
      "uint40", buffer40, 5,
      GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian40
                                                  : little_endian40,
      5);

  uint64_t read_number40 = 0u;
  QuicDataReader reader(buffer40, 5, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadBytesToUInt64(5, &read_number40);
  EXPECT_EQ(in_memory40, read_number40);
}

TEST_P(QuicDataWriterTest, Write48BitUnsignedIntegers) {
  uint64_t in_memory48 = 0x0000112233445566;
  char little_endian48[] = {0x66, 0x55, 0x44, 0x33, 0x22, 0x11};
  char big_endian48[] = {0x11, 0x22, 0x33, 0x44, 0x55, 0x66};
  char buffer48[6];
  QuicDataWriter writer(6, buffer48, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteBytesToUInt64(6, in_memory48);
  test::CompareCharArraysWithHexError(
      "uint48", buffer48, 6,
      GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian48
                                                  : little_endian48,
      6);

  uint64_t read_number48 = 0u;
  QuicDataReader reader(buffer48, 6, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadBytesToUInt64(6., &read_number48);
  EXPECT_EQ(in_memory48, read_number48);
}

TEST_P(QuicDataWriterTest, Write56BitUnsignedIntegers) {
  uint64_t in_memory56 = 0x0011223344556677;
  char little_endian56[] = {0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11};
  char big_endian56[] = {0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77};
  char buffer56[7];
  QuicDataWriter writer(7, buffer56, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteBytesToUInt64(7, in_memory56);
  test::CompareCharArraysWithHexError(
      "uint56", buffer56, 7,
      GetParam().endianness == NETWORK_BYTE_ORDER ? big_endian56
                                                  : little_endian56,
      7);

  uint64_t read_number56 = 0u;
  QuicDataReader reader(buffer56, 7, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadBytesToUInt64(7, &read_number56);
  EXPECT_EQ(in_memory56, read_number56);
}

TEST_P(QuicDataWriterTest, Write64BitUnsignedIntegers) {
  uint64_t in_memory64 = 0x1122334455667788;
  unsigned char little_endian64[] = {0x88, 0x77, 0x66, 0x55,
                                     0x44, 0x33, 0x22, 0x11};
  unsigned char big_endian64[] = {0x11, 0x22, 0x33, 0x44,
                                  0x55, 0x66, 0x77, 0x88};
  char buffer64[8];
  QuicDataWriter writer(8, buffer64, GetParam().perspective,
                        GetParam().endianness);
  writer.WriteBytesToUInt64(8, in_memory64);
  test::CompareCharArraysWithHexError(
      "uint64_t", buffer64, 8,
      GetParam().endianness == NETWORK_BYTE_ORDER ? AsChars(big_endian64)
                                                  : AsChars(little_endian64),
      8);

  uint64_t read_number64 = 0u;
  QuicDataReader reader(buffer64, 8, GetParam().perspective,
                        GetParam().endianness);
  reader.ReadBytesToUInt64(8, &read_number64);
  EXPECT_EQ(in_memory64, read_number64);

  QuicDataWriter writer2(8, buffer64, GetParam().perspective,
                         GetParam().endianness);
  writer2.WriteUInt64(in_memory64);
  test::CompareCharArraysWithHexError(
      "uint64_t", buffer64, 8,
      GetParam().endianness == NETWORK_BYTE_ORDER ? AsChars(big_endian64)
                                                  : AsChars(little_endian64),
      8);
  read_number64 = 0u;
  QuicDataReader reader2(buffer64, 8, GetParam().perspective,
                         GetParam().endianness);
  reader2.ReadUInt64(&read_number64);
  EXPECT_EQ(in_memory64, read_number64);
}

TEST_P(QuicDataWriterTest, WriteIntegers) {
  char buf[43];
  uint8_t i8 = 0x01;
  uint16_t i16 = 0x0123;
  uint32_t i32 = 0x01234567;
  uint64_t i64 = 0x0123456789ABCDEF;
  QuicDataWriter writer(46, buf, GetParam().perspective, GetParam().endianness);
  for (size_t i = 0; i < 10; ++i) {
    switch (i) {
      case 0u:
        EXPECT_TRUE(writer.WriteBytesToUInt64(i, i64));
        break;
      case 1u:
        EXPECT_TRUE(writer.WriteUInt8(i8));
        EXPECT_TRUE(writer.WriteBytesToUInt64(i, i64));
        break;
      case 2u:
        EXPECT_TRUE(writer.WriteUInt16(i16));
        EXPECT_TRUE(writer.WriteBytesToUInt64(i, i64));
        break;
      case 3u:
        EXPECT_TRUE(writer.WriteBytesToUInt64(i, i64));
        break;
      case 4u:
        EXPECT_TRUE(writer.WriteUInt32(i32));
        EXPECT_TRUE(writer.WriteBytesToUInt64(i, i64));
        break;
      case 5u:
      case 6u:
      case 7u:
      case 8u:
        EXPECT_TRUE(writer.WriteBytesToUInt64(i, i64));
        break;
      default:
        EXPECT_FALSE(writer.WriteBytesToUInt64(i, i64));
    }
  }

  QuicDataReader reader(buf, 46, GetParam().perspective, GetParam().endianness);
  for (size_t i = 0; i < 10; ++i) {
    uint8_t read8;
    uint16_t read16;
    uint32_t read32;
    uint64_t read64 = 0u;
    switch (i) {
      case 0u:
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(0u, read64);
        break;
      case 1u:
        EXPECT_TRUE(reader.ReadUInt8(&read8));
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(i8, read8);
        EXPECT_EQ(0xEFu, read64);
        break;
      case 2u:
        EXPECT_TRUE(reader.ReadUInt16(&read16));
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(i16, read16);
        EXPECT_EQ(0xCDEFu, read64);
        break;
      case 3u:
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(0xABCDEFu, read64);
        break;
      case 4u:
        EXPECT_TRUE(reader.ReadUInt32(&read32));
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(i32, read32);
        EXPECT_EQ(0x89ABCDEFu, read64);
        break;
      case 5u:
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(0x6789ABCDEFu, read64);
        break;
      case 6u:
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(0x456789ABCDEFu, read64);
        break;
      case 7u:
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(0x23456789ABCDEFu, read64);
        break;
      case 8u:
        EXPECT_TRUE(reader.ReadBytesToUInt64(i, &read64));
        EXPECT_EQ(0x0123456789ABCDEFu, read64);
        break;
      default:
        EXPECT_FALSE(reader.ReadBytesToUInt64(i, &read64));
    }
  }
}

TEST_P(QuicDataWriterTest, WriteBytes) {
  char bytes[] = {0, 1, 2, 3, 4, 5, 6, 7, 8};
  char buf[arraysize(bytes)];
  QuicDataWriter writer(arraysize(buf), buf, GetParam().perspective,
                        GetParam().endianness);
  EXPECT_TRUE(writer.WriteBytes(bytes, arraysize(bytes)));
  for (unsigned int i = 0; i < arraysize(bytes); ++i) {
    EXPECT_EQ(bytes[i], buf[i]);
  }
}

TEST_P(QuicDataWriterTest, WriteUInt8AtOffset) {
  char bytes[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H'};
  char buf[arraysize(bytes)];
  for (unsigned int i = 0; i < arraysize(bytes); ++i) {
    QuicDataWriter writer(arraysize(buf), buf, GetParam().perspective,
                          GetParam().endianness);
    EXPECT_TRUE(writer.WriteBytes(bytes, arraysize(bytes)));
    EXPECT_TRUE(writer.WriteUInt8AtOffset('I', i));
    for (unsigned int j = 0; j < arraysize(bytes); ++j) {
      if (j == i) {
        EXPECT_EQ('I', buf[j]);
      } else {
        EXPECT_EQ(bytes[j], buf[j]);
      }
    }
  }
}

}  // namespace
}  // namespace test
}  // namespace net