text: // Copyright 2014 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/spdy/core/hpack/hpack_output_stream.h"
  
  #include <cstddef>
  
  #include "testing/gtest/include/gtest/gtest.h"
  
  namespace net {
  
  namespace {
  
  // Make sure that AppendBits() appends bits starting from the most
  // significant bit, and that it can handle crossing a byte boundary.
  TEST(HpackOutputStreamTest, AppendBits) {
    HpackOutputStream output_stream;
    SpdyString expected_str;
  
    output_stream.AppendBits(0x1, 1);
    expected_str.append(1, 0x00);
    expected_str.back() |= (0x1 << 7);
  
    output_stream.AppendBits(0x0, 1);
  
    output_stream.AppendBits(0x3, 2);
    *expected_str.rbegin() |= (0x3 << 4);
  
    output_stream.AppendBits(0x0, 2);
  
    // Byte-crossing append.
    output_stream.AppendBits(0x7, 3);
    *expected_str.rbegin() |= (0x7 >> 1);
    expected_str.append(1, 0x00);
    expected_str.back() |= (0x7 << 7);
  
    output_stream.AppendBits(0x0, 7);
  
    SpdyString str;
    output_stream.TakeString(&str);
    EXPECT_EQ(expected_str, str);
  }
  
  // Utility function to return I as a string encoded with an N-bit
  // prefix.
  SpdyString EncodeUint32(uint8_t N, uint32_t I) {
    HpackOutputStream output_stream;
    if (N < 8) {
      output_stream.AppendBits(0x00, 8 - N);
    }
    output_stream.AppendUint32(I);
    SpdyString str;
    output_stream.TakeString(&str);
    return str;
  }
  
  // The {Number}ByteIntegersEightBitPrefix tests below test that
  // certain integers are encoded correctly with an 8-bit prefix in
  // exactly {Number} bytes.
  
  TEST(HpackOutputStreamTest, OneByteIntegersEightBitPrefix) {
    // Minimum.
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(8, 0x00));
    EXPECT_EQ("\x7f", EncodeUint32(8, 0x7f));
    // Maximum.
    EXPECT_EQ("\xfe", EncodeUint32(8, 0xfe));
  }
  
  TEST(HpackOutputStreamTest, TwoByteIntegersEightBitPrefix) {
    // Minimum.
    EXPECT_EQ(SpdyString("\xff\x00", 2), EncodeUint32(8, 0xff));
    EXPECT_EQ("\xff\x01", EncodeUint32(8, 0x0100));
    // Maximum.
    EXPECT_EQ("\xff\x7f", EncodeUint32(8, 0x017e));
  }
  
  TEST(HpackOutputStreamTest, ThreeByteIntegersEightBitPrefix) {
    // Minimum.
    EXPECT_EQ("\xff\x80\x01", EncodeUint32(8, 0x017f));
    EXPECT_EQ("\xff\x80\x1e", EncodeUint32(8, 0x0fff));
    // Maximum.
    EXPECT_EQ("\xff\xff\x7f", EncodeUint32(8, 0x40fe));
  }
  
  TEST(HpackOutputStreamTest, FourByteIntegersEightBitPrefix) {
    // Minimum.
    EXPECT_EQ("\xff\x80\x80\x01", EncodeUint32(8, 0x40ff));
    EXPECT_EQ("\xff\x80\xfe\x03", EncodeUint32(8, 0xffff));
    // Maximum.
    EXPECT_EQ("\xff\xff\xff\x7f", EncodeUint32(8, 0x002000fe));
  }
  
  TEST(HpackOutputStreamTest, FiveByteIntegersEightBitPrefix) {
    // Minimum.
    EXPECT_EQ("\xff\x80\x80\x80\x01", EncodeUint32(8, 0x002000ff));
    EXPECT_EQ("\xff\x80\xfe\xff\x07", EncodeUint32(8, 0x00ffffff));
    // Maximum.
    EXPECT_EQ("\xff\xff\xff\xff\x7f", EncodeUint32(8, 0x100000fe));
  }
  
  TEST(HpackOutputStreamTest, SixByteIntegersEightBitPrefix) {
    // Minimum.
    EXPECT_EQ("\xff\x80\x80\x80\x80\x01", EncodeUint32(8, 0x100000ff));
    // Maximum.
    EXPECT_EQ("\xff\x80\xfe\xff\xff\x0f", EncodeUint32(8, 0xffffffff));
  }
  
  // The {Number}ByteIntegersOneToSevenBitPrefix tests below test that
  // certain integers are encoded correctly with an N-bit prefix in
  // exactly {Number} bytes for N in {1, 2, ..., 7}.
  
  TEST(HpackOutputStreamTest, OneByteIntegersOneToSevenBitPrefixes) {
    // Minimums.
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(7, 0x00));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(6, 0x00));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(5, 0x00));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(4, 0x00));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(3, 0x00));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(2, 0x00));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(1, 0x00));
  
    // Maximums.
    EXPECT_EQ("\x7e", EncodeUint32(7, 0x7e));
    EXPECT_EQ("\x3e", EncodeUint32(6, 0x3e));
    EXPECT_EQ("\x1e", EncodeUint32(5, 0x1e));
    EXPECT_EQ("\x0e", EncodeUint32(4, 0x0e));
    EXPECT_EQ("\x06", EncodeUint32(3, 0x06));
    EXPECT_EQ("\x02", EncodeUint32(2, 0x02));
    EXPECT_EQ(SpdyString("\x00", 1), EncodeUint32(1, 0x00));
  }
  
  TEST(HpackOutputStreamTest, TwoByteIntegersOneToSevenBitPrefixes) {
    // Minimums.
    EXPECT_EQ(SpdyString("\x7f\x00", 2), EncodeUint32(7, 0x7f));
    EXPECT_EQ(SpdyString("\x3f\x00", 2), EncodeUint32(6, 0x3f));
    EXPECT_EQ(SpdyString("\x1f\x00", 2), EncodeUint32(5, 0x1f));
    EXPECT_EQ(SpdyString("\x0f\x00", 2), EncodeUint32(4, 0x0f));
    EXPECT_EQ(SpdyString("\x07\x00", 2), EncodeUint32(3, 0x07));
    EXPECT_EQ(SpdyString("\x03\x00", 2), EncodeUint32(2, 0x03));
    EXPECT_EQ(SpdyString("\x01\x00", 2), EncodeUint32(1, 0x01));
  
    // Maximums.
    EXPECT_EQ("\x7f\x7f", EncodeUint32(7, 0xfe));
    EXPECT_EQ("\x3f\x7f", EncodeUint32(6, 0xbe));
    EXPECT_EQ("\x1f\x7f", EncodeUint32(5, 0x9e));
    EXPECT_EQ("\x0f\x7f", EncodeUint32(4, 0x8e));
    EXPECT_EQ("\x07\x7f", EncodeUint32(3, 0x86));
    EXPECT_EQ("\x03\x7f", EncodeUint32(2, 0x82));
    EXPECT_EQ("\x01\x7f", EncodeUint32(1, 0x80));
  }
  
  TEST(HpackOutputStreamTest, ThreeByteIntegersOneToSevenBitPrefixes) {
    // Minimums.
    EXPECT_EQ("\x7f\x80\x01", EncodeUint32(7, 0xff));
    EXPECT_EQ("\x3f\x80\x01", EncodeUint32(6, 0xbf));
    EXPECT_EQ("\x1f\x80\x01", EncodeUint32(5, 0x9f));
    EXPECT_EQ("\x0f\x80\x01", EncodeUint32(4, 0x8f));
    EXPECT_EQ("\x07\x80\x01", EncodeUint32(3, 0x87));
    EXPECT_EQ("\x03\x80\x01", EncodeUint32(2, 0x83));
    EXPECT_EQ("\x01\x80\x01", EncodeUint32(1, 0x81));
  
    // Maximums.
    EXPECT_EQ("\x7f\xff\x7f", EncodeUint32(7, 0x407e));
    EXPECT_EQ("\x3f\xff\x7f", EncodeUint32(6, 0x403e));
    EXPECT_EQ("\x1f\xff\x7f", EncodeUint32(5, 0x401e));
    EXPECT_EQ("\x0f\xff\x7f", EncodeUint32(4, 0x400e));
    EXPECT_EQ("\x07\xff\x7f", EncodeUint32(3, 0x4006));
    EXPECT_EQ("\x03\xff\x7f", EncodeUint32(2, 0x4002));
    EXPECT_EQ("\x01\xff\x7f", EncodeUint32(1, 0x4000));
  }
  
  TEST(HpackOutputStreamTest, FourByteIntegersOneToSevenBitPrefixes) {
    // Minimums.
    EXPECT_EQ("\x7f\x80\x80\x01", EncodeUint32(7, 0x407f));
    EXPECT_EQ("\x3f\x80\x80\x01", EncodeUint32(6, 0x403f));
    EXPECT_EQ("\x1f\x80\x80\x01", EncodeUint32(5, 0x401f));
    EXPECT_EQ("\x0f\x80\x80\x01", EncodeUint32(4, 0x400f));
    EXPECT_EQ("\x07\x80\x80\x01", EncodeUint32(3, 0x4007));
    EXPECT_EQ("\x03\x80\x80\x01", EncodeUint32(2, 0x4003));
    EXPECT_EQ("\x01\x80\x80\x01", EncodeUint32(1, 0x4001));
  
    // Maximums.
    EXPECT_EQ("\x7f\xff\xff\x7f", EncodeUint32(7, 0x20007e));
    EXPECT_EQ("\x3f\xff\xff\x7f", EncodeUint32(6, 0x20003e));
    EXPECT_EQ("\x1f\xff\xff\x7f", EncodeUint32(5, 0x20001e));
    EXPECT_EQ("\x0f\xff\xff\x7f", EncodeUint32(4, 0x20000e));
    EXPECT_EQ("\x07\xff\xff\x7f", EncodeUint32(3, 0x200006));
    EXPECT_EQ("\x03\xff\xff\x7f", EncodeUint32(2, 0x200002));
    EXPECT_EQ("\x01\xff\xff\x7f", EncodeUint32(1, 0x200000));
  }
  
  TEST(HpackOutputStreamTest, FiveByteIntegersOneToSevenBitPrefixes) {
    // Minimums.
    EXPECT_EQ("\x7f\x80\x80\x80\x01", EncodeUint32(7, 0x20007f));
    EXPECT_EQ("\x3f\x80\x80\x80\x01", EncodeUint32(6, 0x20003f));
    EXPECT_EQ("\x1f\x80\x80\x80\x01", EncodeUint32(5, 0x20001f));
    EXPECT_EQ("\x0f\x80\x80\x80\x01", EncodeUint32(4, 0x20000f));
    EXPECT_EQ("\x07\x80\x80\x80\x01", EncodeUint32(3, 0x200007));
    EXPECT_EQ("\x03\x80\x80\x80\x01", EncodeUint32(2, 0x200003));
    EXPECT_EQ("\x01\x80\x80\x80\x01", EncodeUint32(1, 0x200001));
  
    // Maximums.
    EXPECT_EQ("\x7f\xff\xff\xff\x7f", EncodeUint32(7, 0x1000007e));
    EXPECT_EQ("\x3f\xff\xff\xff\x7f", EncodeUint32(6, 0x1000003e));
    EXPECT_EQ("\x1f\xff\xff\xff\x7f", EncodeUint32(5, 0x1000001e));
    EXPECT_EQ("\x0f\xff\xff\xff\x7f", EncodeUint32(4, 0x1000000e));
    EXPECT_EQ("\x07\xff\xff\xff\x7f", EncodeUint32(3, 0x10000006));
    EXPECT_EQ("\x03\xff\xff\xff\x7f", EncodeUint32(2, 0x10000002));
    EXPECT_EQ("\x01\xff\xff\xff\x7f", EncodeUint32(1, 0x10000000));
  }
  
  TEST(HpackOutputStreamTest, SixByteIntegersOneToSevenBitPrefixes) {
    // Minimums.
    EXPECT_EQ("\x7f\x80\x80\x80\x80\x01", EncodeUint32(7, 0x1000007f));
    EXPECT_EQ("\x3f\x80\x80\x80\x80\x01", EncodeUint32(6, 0x1000003f));
    EXPECT_EQ("\x1f\x80\x80\x80\x80\x01", EncodeUint32(5, 0x1000001f));
    EXPECT_EQ("\x0f\x80\x80\x80\x80\x01", EncodeUint32(4, 0x1000000f));
    EXPECT_EQ("\x07\x80\x80\x80\x80\x01", EncodeUint32(3, 0x10000007));
    EXPECT_EQ("\x03\x80\x80\x80\x80\x01", EncodeUint32(2, 0x10000003));
    EXPECT_EQ("\x01\x80\x80\x80\x80\x01", EncodeUint32(1, 0x10000001));
  
    // Maximums.
    EXPECT_EQ("\x7f\x80\xff\xff\xff\x0f", EncodeUint32(7, 0xffffffff));
    EXPECT_EQ("\x3f\xc0\xff\xff\xff\x0f", EncodeUint32(6, 0xffffffff));
    EXPECT_EQ("\x1f\xe0\xff\xff\xff\x0f", EncodeUint32(5, 0xffffffff));
    EXPECT_EQ("\x0f\xf0\xff\xff\xff\x0f", EncodeUint32(4, 0xffffffff));
    EXPECT_EQ("\x07\xf8\xff\xff\xff\x0f", EncodeUint32(3, 0xffffffff));
    EXPECT_EQ("\x03\xfc\xff\xff\xff\x0f", EncodeUint32(2, 0xffffffff));
    EXPECT_EQ("\x01\xfe\xff\xff\xff\x0f", EncodeUint32(1, 0xffffffff));
  }
  
  // Test that encoding an integer with an N-bit prefix preserves the
  // upper (8-N) bits of the first byte.
  TEST(HpackOutputStreamTest, AppendUint32PreservesUpperBits) {
    HpackOutputStream output_stream;
    output_stream.AppendBits(0x7f, 7);
    output_stream.AppendUint32(0x01);
    SpdyString str;
    output_stream.TakeString(&str);
    EXPECT_EQ(SpdyString("\xff\x00", 2), str);
  }
  
  TEST(HpackOutputStreamTest, AppendBytes) {
    HpackOutputStream output_stream;
  
    output_stream.AppendBytes("buffer1");
    output_stream.AppendBytes("buffer2");
  
    SpdyString str;
    output_stream.TakeString(&str);
    EXPECT_EQ("buffer1buffer2", str);
  }
  
  TEST(HpackOutputStreamTest, BoundedTakeString) {
    HpackOutputStream output_stream;
  
    output_stream.AppendBytes("buffer12");
    output_stream.AppendBytes("buffer456");
  
    SpdyString str;
    output_stream.BoundedTakeString(9, &str);
    EXPECT_EQ("buffer12b", str);
  
    output_stream.AppendBits(0x7f, 7);
    output_stream.AppendUint32(0x11);
    output_stream.BoundedTakeString(9, &str);
    EXPECT_EQ("uffer456\xff", str);
  
    output_stream.BoundedTakeString(9, &str);
    EXPECT_EQ("\x10", str);
  }
  
  }  // namespace
  
  }  // namespace net
  