reloc_win32_unittest.cc - chromium/src/components/zucchini - Git at Google

 // Copyright 2017 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 "components/zucchini/reloc_win32.h"

 #include <stdint.h>

 #include <algorithm>
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>

 #include "base/numerics/safe_conversions.h"
 #include "base/test/gtest_util.h"
 #include "components/zucchini/address_translator.h"
 #include "components/zucchini/algorithm.h"
 #include "components/zucchini/image_utils.h"
 #include "components/zucchini/test_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"

 namespace zucchini {

 class RelocUtilsWin32Test : public testing::Test {
  protected:
   using Units = std::vector<RelocUnitWin32>;

   RelocUtilsWin32Test() {}

   // Resets all tester data, calls RelocRvaReaderWin32::FindRelocBlocks(), and
   // returns its results.
   bool Initialize(const std::vector<uint8_t>& image_raw,
                   BufferRegion reloc_region) {
     image_ = BufferSource(image_raw.data(), image_raw.size());
     reloc_region_ = reloc_region;
     return RelocRvaReaderWin32::FindRelocBlocks(image_, reloc_region_,
                                                 &reloc_block_offsets_);
   }

   // Uses RelocRvaReaderWin32 to get all relocs, returned as Units.
   Units EmitAll(offset_t lo, offset_t hi) {
     RelocRvaReaderWin32 reader(image_, reloc_region_, reloc_block_offsets_, lo,
                                hi);
     Units units;
     for (auto unit = reader.GetNext(); unit.has_value();
          unit = reader.GetNext()) {
       units.push_back(unit.value());
     }
     return units;
   }

   ConstBufferView image_;
   BufferRegion reloc_region_;
   std::vector<uint32_t> reloc_block_offsets_;
 };

 TEST_F(RelocUtilsWin32Test, RvaReaderEmpty) {
   {
     std::vector<uint8_t> image_raw = ParseHexString("");
     EXPECT_TRUE(Initialize(image_raw, {0U, 0U}));
     EXPECT_EQ(std::vector<uint32_t>(), reloc_block_offsets_);  // Nothing.
     EXPECT_EQ(Units(), EmitAll(0U, 0U));
   }
   {
     std::vector<uint8_t> image_raw = ParseHexString("AA BB CC DD EE FF");
     EXPECT_TRUE(Initialize(image_raw, {2U, 0U}));
     EXPECT_EQ(std::vector<uint32_t>(), reloc_block_offsets_);  // Nothing.
     EXPECT_EQ(Units(), EmitAll(2U, 2U));
   }
   {
     std::vector<uint8_t> image_raw = ParseHexString("00 C0 00 00 08 00 00 00");
     EXPECT_TRUE(Initialize(image_raw, {0U, image_raw.size()}));
     EXPECT_EQ(std::vector<uint32_t>({0U}),
               reloc_block_offsets_);  // Empty block.
     EXPECT_EQ(Units(), EmitAll(0U, 8U));
   }
 }

 TEST_F(RelocUtilsWin32Test, RvaReaderBad) {
   std::string test_cases[] = {
       "00 C0 00 00 07 00 00",           // Header too small.
       "00 C0 00 00 08 00 00",           // Header too small, lies about size.
       "00 C0 00 00 0A 00 00 00 66 31",  // Odd number of units.
       "00 C0 00 00 0C 00 00 00 66 31 88 31 FF",  // Trailing data.
   };
   for (const std::string& test_case : test_cases) {
     std::vector<uint8_t> image_raw = ParseHexString(test_case);
     EXPECT_FALSE(Initialize(image_raw, {0U, image_raw.size()}));
   }
 }

 TEST_F(RelocUtilsWin32Test, RvaReaderSingle) {
   // Block 0: All type 0x3: {0xC166, 0xC288, 0xC342, (padding) 0xCFFF}.
   std::vector<uint8_t> image_raw = ParseHexString(
       "FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF "
       "00 C0 00 00 10 00 00 00 66 31 88 32 42 33 FF 0F "
       "FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF");
   constexpr offset_t kBlock0 = 16U;
   Units exp0 = {{3, kBlock0 + 8U, 0xC166U},
                 {3, kBlock0 + 10U, 0xC288U},
                 {3, kBlock0 + 12U, 0xC342U},
                 {0, kBlock0 + 14U, 0xCFFFU}};

   EXPECT_TRUE(Initialize(image_raw, {16U, 16U}));
   EXPECT_EQ(exp0, EmitAll(kBlock0, kBlock0 + 16U));
   EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0));
   EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0 + 8U));
   EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0 + 9U));
   EXPECT_EQ(Sub(exp0, 0, 1), EmitAll(kBlock0, kBlock0 + 10U));
   EXPECT_EQ(Sub(exp0, 0, 1), EmitAll(kBlock0 + 8U, kBlock0 + 10U));
   EXPECT_EQ(Units(), EmitAll(kBlock0 + 9U, kBlock0 + 10U));
   EXPECT_EQ(Sub(exp0, 0, 3), EmitAll(kBlock0, kBlock0 + 15U));
   EXPECT_EQ(Sub(exp0, 2, 3), EmitAll(kBlock0 + 11U, kBlock0 + 15U));
 }

 TEST_F(RelocUtilsWin32Test, RvaReaderMulti) {
   // The sample image encodes 3 reloc blocks:
   // Block 0: All type 0x3: {0xC166, 0xC288, 0xC344, (padding) 0xCFFF}.
   // Block 1: All type 0x3: {0x12166, 0x12288}.
   // Block 2: All type 0xA: {0x24000, 0x24010, 0x24020, 0x24028, 0x24A3C,
   //                         0x24170}.
   std::vector<uint8_t> image_raw = ParseHexString(
       "FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF "
       "00 C0 00 00 10 00 00 00 66 31 88 32 42 33 FF 0F "
       "00 20 01 00 0C 00 00 00 66 31 88 32 "
       "00 40 02 00 14 00 00 00 00 A0 10 A0 20 A0 28 A0 3C A0 70 A1 "
       "FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF");
   offset_t image_size = base::checked_cast<offset_t>(image_raw.size());
   constexpr offset_t kBlock0 = 16U;
   constexpr offset_t kBlock1 = kBlock0 + 16U;
   constexpr offset_t kBlock2 = kBlock1 + 12U;
   constexpr offset_t kBlockEnd = kBlock2 + 20U;
   Units exp0 = {{3, kBlock0 + 8U, 0xC166U},
                 {3, kBlock0 + 10U, 0xC288U},
                 {3, kBlock0 + 12U, 0xC342U},
                 {0, kBlock0 + 14U, 0xCFFFU}};
   Units exp1 = {{3, kBlock0 + 24U, 0x12166U}, {3, kBlock0 + 26U, 0x12288U}};
   Units exp2 = {{10, kBlock0 + 36U, 0x24000U}, {10, kBlock0 + 38U, 0x24010U},
                 {10, kBlock0 + 40U, 0x24020U}, {10, kBlock0 + 42U, 0x24028U},
                 {10, kBlock0 + 44U, 0x2403CU}, {10, kBlock0 + 46U, 0x24170U}};

   EXPECT_TRUE(Initialize(image_raw, {kBlock0, kBlockEnd - kBlock0}));
   EXPECT_EQ(std::vector<uint32_t>({kBlock0, kBlock1, kBlock2}),
             reloc_block_offsets_);

   // Everything.
   EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(kBlock0, kBlockEnd));
   EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(0, image_size));
   // Entire blocks.
   EXPECT_EQ(exp0, EmitAll(kBlock0, kBlock1));
   EXPECT_EQ(exp1, EmitAll(kBlock1, kBlock2));
   EXPECT_EQ(exp2, EmitAll(kBlock2, kBlockEnd));
   EXPECT_EQ(Units(), EmitAll(0, kBlock0));
   EXPECT_EQ(Units(), EmitAll(kBlockEnd, image_size));
   // Within blocks, clipped at boundaries.
   EXPECT_EQ(exp0, EmitAll(kBlock0 + 5U, kBlock1));
   EXPECT_EQ(exp0, EmitAll(kBlock0 + 8U, kBlock1));
   EXPECT_EQ(Sub(exp0, 1, 4), EmitAll(kBlock0 + 9U, kBlock1));
   EXPECT_EQ(Sub(exp0, 0, 3), EmitAll(kBlock0, kBlock0 + 15U));
   EXPECT_EQ(Sub(exp0, 0, 3), EmitAll(kBlock0, kBlock0 + 14U));
   EXPECT_EQ(Sub(exp0, 0, 1), EmitAll(kBlock0 + 8U, kBlock0 + 10U));
   EXPECT_EQ(Sub(exp1, 1, 2), EmitAll(kBlock1 + 10U, kBlock1 + 12U));
   EXPECT_EQ(Sub(exp2, 2, 4), EmitAll(kBlock2 + 12U, kBlock2 + 16U));
   EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0));
   EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0 + 8U));
   EXPECT_EQ(Units(), EmitAll(kBlock2 + 10U, kBlock2 + 11U));
   EXPECT_EQ(Units(), EmitAll(kBlock2 + 11U, kBlock2 + 12U));
   // Across blocks.
   EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(kBlock0 - 5U, kBlockEnd));
   EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(kBlock0 + 6U, kBlockEnd));
   EXPECT_EQ(Cat(Cat(exp0, exp1), Sub(exp2, 0, 5)),
             EmitAll(kBlock0 + 6U, kBlock2 + 18U));
   EXPECT_EQ(Cat(Sub(exp0, 2, 4), Sub(exp1, 0, 1)),
             EmitAll(kBlock0 + 12U, kBlock1 + 10U));
   EXPECT_EQ(Cat(Sub(exp0, 2, 4), Sub(exp1, 0, 1)),
             EmitAll(kBlock0 + 11U, kBlock1 + 10U));
   EXPECT_EQ(Cat(Sub(exp0, 2, 4), Sub(exp1, 0, 1)),
             EmitAll(kBlock0 + 12U, kBlock1 + 11U));
   EXPECT_EQ(Sub(exp1, 1, 2), EmitAll(kBlock1 + 10U, kBlock2 + 5U));
   EXPECT_EQ(Cat(Sub(exp1, 1, 2), exp2), EmitAll(kBlock1 + 10U, kBlockEnd + 5));
   EXPECT_EQ(Units(), EmitAll(kBlock0 + 15, kBlock1 + 9));
 }

 TEST_F(RelocUtilsWin32Test, ReadWrite) {
   // Set up mock image: Size = 0x3000, .reloc at 0x600. RVA is 0x40000 + offset.
   constexpr rva_t kBaseRva = 0x40000;
   std::vector<uint8_t> image_data(0x3000, 0xFF);
   // 4 x86 relocs (xx 3x), 3 x64 relocs (xx Ax), 1 padding (xx 0X).
   std::vector<uint8_t> reloc_data = ParseHexString(
       "00 10 04 00 10 00 00 00 C0 32 18 A3 F8 A7 FF 0F "
       "00 20 04 00 10 00 00 00 80 A0 65 31 F8 37 BC 3A");
   reloc_region_ = {0x600, reloc_data.size()};
   std::copy(reloc_data.begin(), reloc_data.end(),
             image_data.begin() + reloc_region_.lo());
   image_ = {image_data.data(), image_data.size()};
   offset_t image_size = base::checked_cast<offset_t>(image_.size());

   AddressTranslator translator;
   translator.Initialize({{0, image_size, kBaseRva, image_size}});

   // Precompute |reloc_block_offsets_|.
   EXPECT_TRUE(RelocRvaReaderWin32::FindRelocBlocks(image_, reloc_region_,
                                                    &reloc_block_offsets_));
   EXPECT_EQ(std::vector<uint32_t>({0x600U, 0x610U}), reloc_block_offsets_);

   // Focus on x86.
   constexpr uint16_t kRelocTypeX86 = 3;
   constexpr offset_t kVAWidthX86 = 4;

   // Make RelocRvaReaderWin32.
   RelocRvaReaderWin32 reloc_rva_reader(image_, reloc_region_,
                                        reloc_block_offsets_, 0, image_size);
   offset_t offset_bound = image_size - kVAWidthX86 + 1;

   // Make RelocReaderWin32 that wraps |reloc_rva_reader|.
   auto reader = std::make_unique<RelocReaderWin32>(
       std::move(reloc_rva_reader), kRelocTypeX86, offset_bound, translator);

   // Read all references and check.
   std::vector<Reference> refs;
   for (absl::optional<Reference> ref = reader->GetNext(); ref.has_value();
        ref = reader->GetNext()) {
     refs.push_back(ref.value());
   }
   std::vector<Reference> exp_refs{
       {0x608, 0x12C0}, {0x61A, 0x2165}, {0x61C, 0x27F8}, {0x61E, 0x2ABC}};
   EXPECT_EQ(exp_refs, refs);

   // Write reference, extract bytes and check.
   MutableBufferView mutable_image(&image_data[0], image_data.size());
   auto writer = std::make_unique<RelocWriterWin32>(
       kRelocTypeX86, mutable_image, reloc_region_, reloc_block_offsets_,
       translator);

   writer->PutNext({0x608, 0x1F83});
   std::vector<uint8_t> exp_reloc_data1 = ParseHexString(
       "00 10 04 00 10 00 00 00 83 3F 18 A3 F8 A7 FF 0F "
       "00 20 04 00 10 00 00 00 80 A0 65 31 F8 37 BC 3A");
   EXPECT_EQ(exp_reloc_data1,
             Sub(image_data, reloc_region_.lo(), reloc_region_.hi()));

   writer->PutNext({0x61C, 0x2950});
   std::vector<uint8_t> exp_reloc_data2 = ParseHexString(
       "00 10 04 00 10 00 00 00 83 3F 18 A3 F8 A7 FF 0F "
       "00 20 04 00 10 00 00 00 80 A0 65 31 50 39 BC 3A");
   EXPECT_EQ(exp_reloc_data2,
             Sub(image_data, reloc_region_.lo(), reloc_region_.hi()));
 }

 }  // namespace zucchini
	// Copyright 2017 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 "components/zucchini/reloc_win32.h"

	#include <stdint.h>

	#include <algorithm>
	#include <memory>
	#include <string>
	#include <utility>
	#include <vector>

	#include "base/numerics/safe_conversions.h"
	#include "base/test/gtest_util.h"
	#include "components/zucchini/address_translator.h"
	#include "components/zucchini/algorithm.h"
	#include "components/zucchini/image_utils.h"
	#include "components/zucchini/test_utils.h"
	#include "testing/gtest/include/gtest/gtest.h"

	namespace zucchini {

	class RelocUtilsWin32Test : public testing::Test {
	protected:
	using Units = std::vector<RelocUnitWin32>;

	RelocUtilsWin32Test() {}

	// Resets all tester data, calls RelocRvaReaderWin32::FindRelocBlocks(), and
	// returns its results.
	bool Initialize(const std::vector<uint8_t>& image_raw,
	BufferRegion reloc_region) {
	image_ = BufferSource(image_raw.data(), image_raw.size());
	reloc_region_ = reloc_region;
	return RelocRvaReaderWin32::FindRelocBlocks(image_, reloc_region_,
	&reloc_block_offsets_);
	}

	// Uses RelocRvaReaderWin32 to get all relocs, returned as Units.
	Units EmitAll(offset_t lo, offset_t hi) {
	RelocRvaReaderWin32 reader(image_, reloc_region_, reloc_block_offsets_, lo,
	hi);
	Units units;
	for (auto unit = reader.GetNext(); unit.has_value();
	unit = reader.GetNext()) {
	units.push_back(unit.value());
	}
	return units;
	}

	ConstBufferView image_;
	BufferRegion reloc_region_;
	std::vector<uint32_t> reloc_block_offsets_;
	};

	TEST_F(RelocUtilsWin32Test, RvaReaderEmpty) {
	{
	std::vector<uint8_t> image_raw = ParseHexString("");
	EXPECT_TRUE(Initialize(image_raw, {0U, 0U}));
	EXPECT_EQ(std::vector<uint32_t>(), reloc_block_offsets_); // Nothing.
	EXPECT_EQ(Units(), EmitAll(0U, 0U));
	}
	{
	std::vector<uint8_t> image_raw = ParseHexString("AA BB CC DD EE FF");
	EXPECT_TRUE(Initialize(image_raw, {2U, 0U}));
	EXPECT_EQ(std::vector<uint32_t>(), reloc_block_offsets_); // Nothing.
	EXPECT_EQ(Units(), EmitAll(2U, 2U));
	}
	{
	std::vector<uint8_t> image_raw = ParseHexString("00 C0 00 00 08 00 00 00");
	EXPECT_TRUE(Initialize(image_raw, {0U, image_raw.size()}));
	EXPECT_EQ(std::vector<uint32_t>({0U}),
	reloc_block_offsets_); // Empty block.
	EXPECT_EQ(Units(), EmitAll(0U, 8U));
	}
	}

	TEST_F(RelocUtilsWin32Test, RvaReaderBad) {
	std::string test_cases[] = {
	"00 C0 00 00 07 00 00", // Header too small.
	"00 C0 00 00 08 00 00", // Header too small, lies about size.
	"00 C0 00 00 0A 00 00 00 66 31", // Odd number of units.
	"00 C0 00 00 0C 00 00 00 66 31 88 31 FF", // Trailing data.
	};
	for (const std::string& test_case : test_cases) {
	std::vector<uint8_t> image_raw = ParseHexString(test_case);
	EXPECT_FALSE(Initialize(image_raw, {0U, image_raw.size()}));
	}
	}

	TEST_F(RelocUtilsWin32Test, RvaReaderSingle) {
	// Block 0: All type 0x3: {0xC166, 0xC288, 0xC342, (padding) 0xCFFF}.
	std::vector<uint8_t> image_raw = ParseHexString(
	"FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF "
	"00 C0 00 00 10 00 00 00 66 31 88 32 42 33 FF 0F "
	"FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF");
	constexpr offset_t kBlock0 = 16U;
	Units exp0 = {{3, kBlock0 + 8U, 0xC166U},
	{3, kBlock0 + 10U, 0xC288U},
	{3, kBlock0 + 12U, 0xC342U},
	{0, kBlock0 + 14U, 0xCFFFU}};

	EXPECT_TRUE(Initialize(image_raw, {16U, 16U}));
	EXPECT_EQ(exp0, EmitAll(kBlock0, kBlock0 + 16U));
	EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0));
	EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0 + 8U));
	EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0 + 9U));
	EXPECT_EQ(Sub(exp0, 0, 1), EmitAll(kBlock0, kBlock0 + 10U));
	EXPECT_EQ(Sub(exp0, 0, 1), EmitAll(kBlock0 + 8U, kBlock0 + 10U));
	EXPECT_EQ(Units(), EmitAll(kBlock0 + 9U, kBlock0 + 10U));
	EXPECT_EQ(Sub(exp0, 0, 3), EmitAll(kBlock0, kBlock0 + 15U));
	EXPECT_EQ(Sub(exp0, 2, 3), EmitAll(kBlock0 + 11U, kBlock0 + 15U));
	}

	TEST_F(RelocUtilsWin32Test, RvaReaderMulti) {
	// The sample image encodes 3 reloc blocks:
	// Block 0: All type 0x3: {0xC166, 0xC288, 0xC344, (padding) 0xCFFF}.
	// Block 1: All type 0x3: {0x12166, 0x12288}.
	// Block 2: All type 0xA: {0x24000, 0x24010, 0x24020, 0x24028, 0x24A3C,
	// 0x24170}.
	std::vector<uint8_t> image_raw = ParseHexString(
	"FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF "
	"00 C0 00 00 10 00 00 00 66 31 88 32 42 33 FF 0F "
	"00 20 01 00 0C 00 00 00 66 31 88 32 "
	"00 40 02 00 14 00 00 00 00 A0 10 A0 20 A0 28 A0 3C A0 70 A1 "
	"FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF");
	offset_t image_size = base::checked_cast<offset_t>(image_raw.size());
	constexpr offset_t kBlock0 = 16U;
	constexpr offset_t kBlock1 = kBlock0 + 16U;
	constexpr offset_t kBlock2 = kBlock1 + 12U;
	constexpr offset_t kBlockEnd = kBlock2 + 20U;
	Units exp0 = {{3, kBlock0 + 8U, 0xC166U},
	{3, kBlock0 + 10U, 0xC288U},
	{3, kBlock0 + 12U, 0xC342U},
	{0, kBlock0 + 14U, 0xCFFFU}};
	Units exp1 = {{3, kBlock0 + 24U, 0x12166U}, {3, kBlock0 + 26U, 0x12288U}};
	Units exp2 = {{10, kBlock0 + 36U, 0x24000U}, {10, kBlock0 + 38U, 0x24010U},
	{10, kBlock0 + 40U, 0x24020U}, {10, kBlock0 + 42U, 0x24028U},
	{10, kBlock0 + 44U, 0x2403CU}, {10, kBlock0 + 46U, 0x24170U}};

	EXPECT_TRUE(Initialize(image_raw, {kBlock0, kBlockEnd - kBlock0}));
	EXPECT_EQ(std::vector<uint32_t>({kBlock0, kBlock1, kBlock2}),
	reloc_block_offsets_);

	// Everything.
	EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(kBlock0, kBlockEnd));
	EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(0, image_size));
	// Entire blocks.
	EXPECT_EQ(exp0, EmitAll(kBlock0, kBlock1));
	EXPECT_EQ(exp1, EmitAll(kBlock1, kBlock2));
	EXPECT_EQ(exp2, EmitAll(kBlock2, kBlockEnd));
	EXPECT_EQ(Units(), EmitAll(0, kBlock0));
	EXPECT_EQ(Units(), EmitAll(kBlockEnd, image_size));
	// Within blocks, clipped at boundaries.
	EXPECT_EQ(exp0, EmitAll(kBlock0 + 5U, kBlock1));
	EXPECT_EQ(exp0, EmitAll(kBlock0 + 8U, kBlock1));
	EXPECT_EQ(Sub(exp0, 1, 4), EmitAll(kBlock0 + 9U, kBlock1));
	EXPECT_EQ(Sub(exp0, 0, 3), EmitAll(kBlock0, kBlock0 + 15U));
	EXPECT_EQ(Sub(exp0, 0, 3), EmitAll(kBlock0, kBlock0 + 14U));
	EXPECT_EQ(Sub(exp0, 0, 1), EmitAll(kBlock0 + 8U, kBlock0 + 10U));
	EXPECT_EQ(Sub(exp1, 1, 2), EmitAll(kBlock1 + 10U, kBlock1 + 12U));
	EXPECT_EQ(Sub(exp2, 2, 4), EmitAll(kBlock2 + 12U, kBlock2 + 16U));
	EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0));
	EXPECT_EQ(Units(), EmitAll(kBlock0, kBlock0 + 8U));
	EXPECT_EQ(Units(), EmitAll(kBlock2 + 10U, kBlock2 + 11U));
	EXPECT_EQ(Units(), EmitAll(kBlock2 + 11U, kBlock2 + 12U));
	// Across blocks.
	EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(kBlock0 - 5U, kBlockEnd));
	EXPECT_EQ(Cat(Cat(exp0, exp1), exp2), EmitAll(kBlock0 + 6U, kBlockEnd));
	EXPECT_EQ(Cat(Cat(exp0, exp1), Sub(exp2, 0, 5)),
	EmitAll(kBlock0 + 6U, kBlock2 + 18U));
	EXPECT_EQ(Cat(Sub(exp0, 2, 4), Sub(exp1, 0, 1)),
	EmitAll(kBlock0 + 12U, kBlock1 + 10U));
	EXPECT_EQ(Cat(Sub(exp0, 2, 4), Sub(exp1, 0, 1)),
	EmitAll(kBlock0 + 11U, kBlock1 + 10U));
	EXPECT_EQ(Cat(Sub(exp0, 2, 4), Sub(exp1, 0, 1)),
	EmitAll(kBlock0 + 12U, kBlock1 + 11U));
	EXPECT_EQ(Sub(exp1, 1, 2), EmitAll(kBlock1 + 10U, kBlock2 + 5U));
	EXPECT_EQ(Cat(Sub(exp1, 1, 2), exp2), EmitAll(kBlock1 + 10U, kBlockEnd + 5));
	EXPECT_EQ(Units(), EmitAll(kBlock0 + 15, kBlock1 + 9));
	}

	TEST_F(RelocUtilsWin32Test, ReadWrite) {
	// Set up mock image: Size = 0x3000, .reloc at 0x600. RVA is 0x40000 + offset.
	constexpr rva_t kBaseRva = 0x40000;
	std::vector<uint8_t> image_data(0x3000, 0xFF);
	// 4 x86 relocs (xx 3x), 3 x64 relocs (xx Ax), 1 padding (xx 0X).
	std::vector<uint8_t> reloc_data = ParseHexString(
	"00 10 04 00 10 00 00 00 C0 32 18 A3 F8 A7 FF 0F "
	"00 20 04 00 10 00 00 00 80 A0 65 31 F8 37 BC 3A");
	reloc_region_ = {0x600, reloc_data.size()};
	std::copy(reloc_data.begin(), reloc_data.end(),
	image_data.begin() + reloc_region_.lo());
	image_ = {image_data.data(), image_data.size()};
	offset_t image_size = base::checked_cast<offset_t>(image_.size());

	AddressTranslator translator;
	translator.Initialize({{0, image_size, kBaseRva, image_size}});

	// Precompute \|reloc_block_offsets_\|.
	EXPECT_TRUE(RelocRvaReaderWin32::FindRelocBlocks(image_, reloc_region_,
	&reloc_block_offsets_));
	EXPECT_EQ(std::vector<uint32_t>({0x600U, 0x610U}), reloc_block_offsets_);

	// Focus on x86.
	constexpr uint16_t kRelocTypeX86 = 3;
	constexpr offset_t kVAWidthX86 = 4;

	// Make RelocRvaReaderWin32.
	RelocRvaReaderWin32 reloc_rva_reader(image_, reloc_region_,
	reloc_block_offsets_, 0, image_size);
	offset_t offset_bound = image_size - kVAWidthX86 + 1;

	// Make RelocReaderWin32 that wraps \|reloc_rva_reader\|.
	auto reader = std::make_unique<RelocReaderWin32>(
	std::move(reloc_rva_reader), kRelocTypeX86, offset_bound, translator);

	// Read all references and check.
	std::vector<Reference> refs;
	for (absl::optional<Reference> ref = reader->GetNext(); ref.has_value();
	ref = reader->GetNext()) {
	refs.push_back(ref.value());
	}
	std::vector<Reference> exp_refs{
	{0x608, 0x12C0}, {0x61A, 0x2165}, {0x61C, 0x27F8}, {0x61E, 0x2ABC}};
	EXPECT_EQ(exp_refs, refs);

	// Write reference, extract bytes and check.
	MutableBufferView mutable_image(&image_data[0], image_data.size());
	auto writer = std::make_unique<RelocWriterWin32>(
	kRelocTypeX86, mutable_image, reloc_region_, reloc_block_offsets_,
	translator);

	writer->PutNext({0x608, 0x1F83});
	std::vector<uint8_t> exp_reloc_data1 = ParseHexString(
	"00 10 04 00 10 00 00 00 83 3F 18 A3 F8 A7 FF 0F "
	"00 20 04 00 10 00 00 00 80 A0 65 31 F8 37 BC 3A");
	EXPECT_EQ(exp_reloc_data1,
	Sub(image_data, reloc_region_.lo(), reloc_region_.hi()));

	writer->PutNext({0x61C, 0x2950});
	std::vector<uint8_t> exp_reloc_data2 = ParseHexString(
	"00 10 04 00 10 00 00 00 83 3F 18 A3 F8 A7 FF 0F "
	"00 20 04 00 10 00 00 00 80 A0 65 31 50 39 BC 3A");
	EXPECT_EQ(exp_reloc_data2,
	Sub(image_data, reloc_region_.lo(), reloc_region_.hi()));
	}

	} // namespace zucchini