libs/androidfw/tests/BackupData_test.cpp - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * 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
  *
  *      http://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.
  */

 #define LOG_TAG "ObbFile_test"
 #include <androidfw/BackupHelpers.h>
 #include <utils/Log.h>
 #include <utils/String8.h>

 #include <gtest/gtest.h>

 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
 #include <string.h>

 namespace android {

 #define TEST_FILENAME "/test.bd"

 // keys of different lengths to test padding
 #define KEY1 "key1"
 #define KEY2 "key2a"
 #define KEY3 "key3bc"
 #define KEY4 "key4def"

 // payloads of different lengths to test padding
 #define DATA1 "abcdefg"
 #define DATA2 "hijklmnopq"
 #define DATA3 "rstuvwxyz"
 // KEY4 is only ever deleted

 class BackupDataTest : public testing::Test {
 protected:
     char* m_external_storage;
     String8 mFilename;
     String8 mKey1;
     String8 mKey2;
     String8 mKey3;
     String8 mKey4;

     virtual void SetUp() {
         m_external_storage = getenv("EXTERNAL_STORAGE");
         mFilename.append(m_external_storage);
         mFilename.append(TEST_FILENAME);

         ::unlink(mFilename.string());
         int fd = ::open(mFilename.string(), O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
         if (fd < 0) {
             FAIL() << "Couldn't create " << mFilename.string() << " for writing";
         }
         mKey1 = String8(KEY1);
         mKey2 = String8(KEY2);
         mKey3 = String8(KEY3);
         mKey4 = String8(KEY4);
    }

     virtual void TearDown() {
     }
 };

 TEST_F(BackupDataTest, WriteAndReadSingle) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);

   EXPECT_EQ(NO_ERROR, writer->WriteEntityHeader(mKey1, sizeof(DATA1)))
           << "WriteEntityHeader returned an error";
   EXPECT_EQ(NO_ERROR, writer->WriteEntityData(DATA1, sizeof(DATA1)))
           << "WriteEntityData returned an error";

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);
   EXPECT_EQ(NO_ERROR, reader->Status())
           << "Reader ctor failed";

   bool done;
   int type;
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader";

   String8 key;
   size_t dataSize;
   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error";
   EXPECT_EQ(mKey1, key)
           << "wrong key from ReadEntityHeader";
   EXPECT_EQ(sizeof(DATA1), dataSize)
           << "wrong size from ReadEntityHeader";

   char* dataBytes = new char[dataSize];
   EXPECT_EQ((int) dataSize, reader->ReadEntityData(dataBytes, dataSize))
           << "ReadEntityData returned an error";
   for (unsigned int i = 0; i < sizeof(DATA1); i++) {
     EXPECT_EQ(DATA1[i], dataBytes[i])
              << "data character " << i << " should be equal";
   }
   delete[] dataBytes;
   delete writer;
   delete reader;
 }

 TEST_F(BackupDataTest, WriteAndReadMultiple) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);
   writer->WriteEntityHeader(mKey1, sizeof(DATA1));
   writer->WriteEntityData(DATA1, sizeof(DATA1));
   writer->WriteEntityHeader(mKey2, sizeof(DATA2));
   writer->WriteEntityData(DATA2, sizeof(DATA2));

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);

   bool done;
   int type;
   String8 key;
   size_t dataSize;
   char* dataBytes;
   // read first entity
   reader->ReadNextHeader(&done, &type);
   reader->ReadEntityHeader(&key, &dataSize);
   dataBytes = new char[dataSize];
   reader->ReadEntityData(dataBytes, dataSize);
   delete dataBytes;

   // read and verify second entity
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on second entity";
   EXPECT_EQ(mKey2, key)
           << "wrong key from ReadEntityHeader on second entity";
   EXPECT_EQ(sizeof(DATA2), dataSize)
           << "wrong size from ReadEntityHeader on second entity";

   dataBytes = new char[dataSize];
   EXPECT_EQ((int)dataSize, reader->ReadEntityData(dataBytes, dataSize))
           << "ReadEntityData returned an error on second entity";
   for (unsigned int i = 0; i < sizeof(DATA2); i++) {
     EXPECT_EQ(DATA2[i], dataBytes[i])
              << "data character " << i << " should be equal";
   }
   delete dataBytes;
   delete writer;
   delete reader;
 }

 TEST_F(BackupDataTest, SkipEntity) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);
   writer->WriteEntityHeader(mKey1, sizeof(DATA1));
   writer->WriteEntityData(DATA1, sizeof(DATA1));
   writer->WriteEntityHeader(mKey2, sizeof(DATA2));
   writer->WriteEntityData(DATA2, sizeof(DATA2));
   writer->WriteEntityHeader(mKey3, sizeof(DATA3));
   writer->WriteEntityData(DATA3, sizeof(DATA3));

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);

   bool done;
   int type;
   String8 key;
   size_t dataSize;
   char* dataBytes;
   // read first entity
   reader->ReadNextHeader(&done, &type);
   reader->ReadEntityHeader(&key, &dataSize);
   dataBytes = new char[dataSize];
   reader->ReadEntityData(dataBytes, dataSize);
   delete dataBytes;

   // skip second entity
   reader->ReadNextHeader(&done, &type);
   reader->ReadEntityHeader(&key, &dataSize);
   reader->SkipEntityData();

   // read and verify third entity
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader after skip";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on third entity";
   EXPECT_EQ(mKey3, key)
           << "wrong key from ReadEntityHeader on third entity";
   EXPECT_EQ(sizeof(DATA3), dataSize)
           << "wrong size from ReadEntityHeader on third entity";

   dataBytes = new char[dataSize];
   EXPECT_EQ((int) dataSize, reader->ReadEntityData(dataBytes, dataSize))
           << "ReadEntityData returned an error on third entity";
   for (unsigned int i = 0; i < sizeof(DATA3); i++) {
     EXPECT_EQ(DATA3[i], dataBytes[i])
              << "data character " << i << " should be equal";
   }
   delete dataBytes;
   delete writer;
   delete reader;
 }

 TEST_F(BackupDataTest, DeleteEntity) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);
   writer->WriteEntityHeader(mKey1, sizeof(DATA1));
   writer->WriteEntityData(DATA1, sizeof(DATA1));
   writer->WriteEntityHeader(mKey2, -1);

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);

   bool done;
   int type;
   String8 key;
   size_t dataSize;
   char* dataBytes;
   // read first entity
   reader->ReadNextHeader(&done, &type);
   reader->ReadEntityHeader(&key, &dataSize);
   dataBytes = new char[dataSize];
   reader->ReadEntityData(dataBytes, dataSize);
   delete dataBytes;

   // read and verify deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader on deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on second entity";
   EXPECT_EQ(mKey2, key)
           << "wrong key from ReadEntityHeader on second entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on second entity";

   delete writer;
   delete reader;
 }

 TEST_F(BackupDataTest, EneityAfterDelete) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);
   writer->WriteEntityHeader(mKey1, sizeof(DATA1));
   writer->WriteEntityData(DATA1, sizeof(DATA1));
   writer->WriteEntityHeader(mKey2, -1);
   writer->WriteEntityHeader(mKey3, sizeof(DATA3));
   writer->WriteEntityData(DATA3, sizeof(DATA3));

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);

   bool done;
   int type;
   String8 key;
   size_t dataSize;
   char* dataBytes;
   // read first entity
   reader->ReadNextHeader(&done, &type);
   reader->ReadEntityHeader(&key, &dataSize);
   dataBytes = new char[dataSize];
   reader->ReadEntityData(dataBytes, dataSize);
   delete dataBytes;

   // read and verify deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader on deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on second entity";
   EXPECT_EQ(mKey2, key)
           << "wrong key from ReadEntityHeader on second entity";
   EXPECT_EQ(-1, (int)dataSize)
           << "not recognizing deletion on second entity";

   // read and verify third entity
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader after deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on third entity";
   EXPECT_EQ(mKey3, key)
           << "wrong key from ReadEntityHeader on third entity";
   EXPECT_EQ(sizeof(DATA3), dataSize)
           << "wrong size from ReadEntityHeader on third entity";

   dataBytes = new char[dataSize];
   EXPECT_EQ((int) dataSize, reader->ReadEntityData(dataBytes, dataSize))
           << "ReadEntityData returned an error on third entity";
   for (unsigned int i = 0; i < sizeof(DATA3); i++) {
     EXPECT_EQ(DATA3[i], dataBytes[i])
              << "data character " << i << " should be equal";
   }
   delete dataBytes;
   delete writer;
   delete reader;
 }

 TEST_F(BackupDataTest, OnlyDeleteEntities) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);
   writer->WriteEntityHeader(mKey1, -1);
   writer->WriteEntityHeader(mKey2, -1);
   writer->WriteEntityHeader(mKey3, -1);
   writer->WriteEntityHeader(mKey4, -1);

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);

   bool done;
   int type;
   String8 key;
   size_t dataSize;
   // read and verify first deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader first deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on first entity";
   EXPECT_EQ(mKey1, key)
           << "wrong key from ReadEntityHeader on first entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on first entity";

   // read and verify second deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader second deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on second entity";
   EXPECT_EQ(mKey2, key)
           << "wrong key from ReadEntityHeader on second entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on second entity";

   // read and verify third deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader third deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on third entity";
   EXPECT_EQ(mKey3, key)
           << "wrong key from ReadEntityHeader on third entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on third entity";

   // read and verify fourth deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader fourth deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on fourth entity";
   EXPECT_EQ(mKey4, key)
           << "wrong key from ReadEntityHeader on fourth entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on fourth entity";

   delete writer;
   delete reader;
 }

 TEST_F(BackupDataTest, ReadDeletedEntityData) {
   int fd = ::open(mFilename.string(), O_WRONLY);
   BackupDataWriter* writer = new BackupDataWriter(fd);
   writer->WriteEntityHeader(mKey1, -1);
   writer->WriteEntityHeader(mKey2, -1);

   ::close(fd);
   fd = ::open(mFilename.string(), O_RDONLY);
   BackupDataReader* reader = new BackupDataReader(fd);

   bool done;
   int type;
   String8 key;
   size_t dataSize;
   // read and verify first deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader first deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on first entity";
   EXPECT_EQ(mKey1, key)
           << "wrong key from ReadEntityHeader on first entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on first entity";

   // erroneously try to read first entity data
   char* dataBytes = new char[10];
   dataBytes[0] = 'A';
   EXPECT_EQ(NO_ERROR, reader->ReadEntityData(dataBytes, dataSize));
   // expect dataBytes to be unmodofied
   EXPECT_EQ('A', dataBytes[0]);

   // read and verify second deletion
   reader->ReadNextHeader(&done, &type);
   EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
           << "wrong type from ReadNextHeader second deletion";

   EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
           << "ReadEntityHeader returned an error on second entity";
   EXPECT_EQ(mKey2, key)
           << "wrong key from ReadEntityHeader on second entity";
   EXPECT_EQ(-1, (int) dataSize)
           << "not recognizing deletion on second entity";

   delete[] dataBytes;
   delete writer;
   delete reader;
 }

 }
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* 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
	*
	* http://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.
	*/

	#define LOG_TAG "ObbFile_test"
	#include <androidfw/BackupHelpers.h>
	#include <utils/Log.h>
	#include <utils/String8.h>

	#include <gtest/gtest.h>

	#include <sys/types.h>
	#include <sys/stat.h>
	#include <fcntl.h>
	#include <string.h>

	namespace android {

	#define TEST_FILENAME "/test.bd"

	// keys of different lengths to test padding
	#define KEY1 "key1"
	#define KEY2 "key2a"
	#define KEY3 "key3bc"
	#define KEY4 "key4def"

	// payloads of different lengths to test padding
	#define DATA1 "abcdefg"
	#define DATA2 "hijklmnopq"
	#define DATA3 "rstuvwxyz"
	// KEY4 is only ever deleted

	class BackupDataTest : public testing::Test {
	protected:
	char* m_external_storage;
	String8 mFilename;
	String8 mKey1;
	String8 mKey2;
	String8 mKey3;
	String8 mKey4;

	virtual void SetUp() {
	m_external_storage = getenv("EXTERNAL_STORAGE");
	mFilename.append(m_external_storage);
	mFilename.append(TEST_FILENAME);

	::unlink(mFilename.string());
	int fd = ::open(mFilename.string(), O_CREAT \| O_TRUNC, S_IRUSR \| S_IWUSR);
	if (fd < 0) {
	FAIL() << "Couldn't create " << mFilename.string() << " for writing";
	}
	mKey1 = String8(KEY1);
	mKey2 = String8(KEY2);
	mKey3 = String8(KEY3);
	mKey4 = String8(KEY4);
	}

	virtual void TearDown() {
	}
	};

	TEST_F(BackupDataTest, WriteAndReadSingle) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);

	EXPECT_EQ(NO_ERROR, writer->WriteEntityHeader(mKey1, sizeof(DATA1)))
	<< "WriteEntityHeader returned an error";
	EXPECT_EQ(NO_ERROR, writer->WriteEntityData(DATA1, sizeof(DATA1)))
	<< "WriteEntityData returned an error";

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);
	EXPECT_EQ(NO_ERROR, reader->Status())
	<< "Reader ctor failed";

	bool done;
	int type;
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader";

	String8 key;
	size_t dataSize;
	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error";
	EXPECT_EQ(mKey1, key)
	<< "wrong key from ReadEntityHeader";
	EXPECT_EQ(sizeof(DATA1), dataSize)
	<< "wrong size from ReadEntityHeader";

	char* dataBytes = new char[dataSize];
	EXPECT_EQ((int) dataSize, reader->ReadEntityData(dataBytes, dataSize))
	<< "ReadEntityData returned an error";
	for (unsigned int i = 0; i < sizeof(DATA1); i++) {
	EXPECT_EQ(DATA1[i], dataBytes[i])
	<< "data character " << i << " should be equal";
	}
	delete[] dataBytes;
	delete writer;
	delete reader;
	}

	TEST_F(BackupDataTest, WriteAndReadMultiple) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);
	writer->WriteEntityHeader(mKey1, sizeof(DATA1));
	writer->WriteEntityData(DATA1, sizeof(DATA1));
	writer->WriteEntityHeader(mKey2, sizeof(DATA2));
	writer->WriteEntityData(DATA2, sizeof(DATA2));

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);

	bool done;
	int type;
	String8 key;
	size_t dataSize;
	char* dataBytes;
	// read first entity
	reader->ReadNextHeader(&done, &type);
	reader->ReadEntityHeader(&key, &dataSize);
	dataBytes = new char[dataSize];
	reader->ReadEntityData(dataBytes, dataSize);
	delete dataBytes;

	// read and verify second entity
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on second entity";
	EXPECT_EQ(mKey2, key)
	<< "wrong key from ReadEntityHeader on second entity";
	EXPECT_EQ(sizeof(DATA2), dataSize)
	<< "wrong size from ReadEntityHeader on second entity";

	dataBytes = new char[dataSize];
	EXPECT_EQ((int)dataSize, reader->ReadEntityData(dataBytes, dataSize))
	<< "ReadEntityData returned an error on second entity";
	for (unsigned int i = 0; i < sizeof(DATA2); i++) {
	EXPECT_EQ(DATA2[i], dataBytes[i])
	<< "data character " << i << " should be equal";
	}
	delete dataBytes;
	delete writer;
	delete reader;
	}

	TEST_F(BackupDataTest, SkipEntity) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);
	writer->WriteEntityHeader(mKey1, sizeof(DATA1));
	writer->WriteEntityData(DATA1, sizeof(DATA1));
	writer->WriteEntityHeader(mKey2, sizeof(DATA2));
	writer->WriteEntityData(DATA2, sizeof(DATA2));
	writer->WriteEntityHeader(mKey3, sizeof(DATA3));
	writer->WriteEntityData(DATA3, sizeof(DATA3));

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);

	bool done;
	int type;
	String8 key;
	size_t dataSize;
	char* dataBytes;
	// read first entity
	reader->ReadNextHeader(&done, &type);
	reader->ReadEntityHeader(&key, &dataSize);
	dataBytes = new char[dataSize];
	reader->ReadEntityData(dataBytes, dataSize);
	delete dataBytes;

	// skip second entity
	reader->ReadNextHeader(&done, &type);
	reader->ReadEntityHeader(&key, &dataSize);
	reader->SkipEntityData();

	// read and verify third entity
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader after skip";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on third entity";
	EXPECT_EQ(mKey3, key)
	<< "wrong key from ReadEntityHeader on third entity";
	EXPECT_EQ(sizeof(DATA3), dataSize)
	<< "wrong size from ReadEntityHeader on third entity";

	dataBytes = new char[dataSize];
	EXPECT_EQ((int) dataSize, reader->ReadEntityData(dataBytes, dataSize))
	<< "ReadEntityData returned an error on third entity";
	for (unsigned int i = 0; i < sizeof(DATA3); i++) {
	EXPECT_EQ(DATA3[i], dataBytes[i])
	<< "data character " << i << " should be equal";
	}
	delete dataBytes;
	delete writer;
	delete reader;
	}

	TEST_F(BackupDataTest, DeleteEntity) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);
	writer->WriteEntityHeader(mKey1, sizeof(DATA1));
	writer->WriteEntityData(DATA1, sizeof(DATA1));
	writer->WriteEntityHeader(mKey2, -1);

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);

	bool done;
	int type;
	String8 key;
	size_t dataSize;
	char* dataBytes;
	// read first entity
	reader->ReadNextHeader(&done, &type);
	reader->ReadEntityHeader(&key, &dataSize);
	dataBytes = new char[dataSize];
	reader->ReadEntityData(dataBytes, dataSize);
	delete dataBytes;

	// read and verify deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader on deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on second entity";
	EXPECT_EQ(mKey2, key)
	<< "wrong key from ReadEntityHeader on second entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on second entity";

	delete writer;
	delete reader;
	}

	TEST_F(BackupDataTest, EneityAfterDelete) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);
	writer->WriteEntityHeader(mKey1, sizeof(DATA1));
	writer->WriteEntityData(DATA1, sizeof(DATA1));
	writer->WriteEntityHeader(mKey2, -1);
	writer->WriteEntityHeader(mKey3, sizeof(DATA3));
	writer->WriteEntityData(DATA3, sizeof(DATA3));

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);

	bool done;
	int type;
	String8 key;
	size_t dataSize;
	char* dataBytes;
	// read first entity
	reader->ReadNextHeader(&done, &type);
	reader->ReadEntityHeader(&key, &dataSize);
	dataBytes = new char[dataSize];
	reader->ReadEntityData(dataBytes, dataSize);
	delete dataBytes;

	// read and verify deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader on deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on second entity";
	EXPECT_EQ(mKey2, key)
	<< "wrong key from ReadEntityHeader on second entity";
	EXPECT_EQ(-1, (int)dataSize)
	<< "not recognizing deletion on second entity";

	// read and verify third entity
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader after deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on third entity";
	EXPECT_EQ(mKey3, key)
	<< "wrong key from ReadEntityHeader on third entity";
	EXPECT_EQ(sizeof(DATA3), dataSize)
	<< "wrong size from ReadEntityHeader on third entity";

	dataBytes = new char[dataSize];
	EXPECT_EQ((int) dataSize, reader->ReadEntityData(dataBytes, dataSize))
	<< "ReadEntityData returned an error on third entity";
	for (unsigned int i = 0; i < sizeof(DATA3); i++) {
	EXPECT_EQ(DATA3[i], dataBytes[i])
	<< "data character " << i << " should be equal";
	}
	delete dataBytes;
	delete writer;
	delete reader;
	}

	TEST_F(BackupDataTest, OnlyDeleteEntities) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);
	writer->WriteEntityHeader(mKey1, -1);
	writer->WriteEntityHeader(mKey2, -1);
	writer->WriteEntityHeader(mKey3, -1);
	writer->WriteEntityHeader(mKey4, -1);

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);

	bool done;
	int type;
	String8 key;
	size_t dataSize;
	// read and verify first deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader first deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on first entity";
	EXPECT_EQ(mKey1, key)
	<< "wrong key from ReadEntityHeader on first entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on first entity";

	// read and verify second deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader second deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on second entity";
	EXPECT_EQ(mKey2, key)
	<< "wrong key from ReadEntityHeader on second entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on second entity";

	// read and verify third deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader third deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on third entity";
	EXPECT_EQ(mKey3, key)
	<< "wrong key from ReadEntityHeader on third entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on third entity";

	// read and verify fourth deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader fourth deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on fourth entity";
	EXPECT_EQ(mKey4, key)
	<< "wrong key from ReadEntityHeader on fourth entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on fourth entity";

	delete writer;
	delete reader;
	}

	TEST_F(BackupDataTest, ReadDeletedEntityData) {
	int fd = ::open(mFilename.string(), O_WRONLY);
	BackupDataWriter* writer = new BackupDataWriter(fd);
	writer->WriteEntityHeader(mKey1, -1);
	writer->WriteEntityHeader(mKey2, -1);

	::close(fd);
	fd = ::open(mFilename.string(), O_RDONLY);
	BackupDataReader* reader = new BackupDataReader(fd);

	bool done;
	int type;
	String8 key;
	size_t dataSize;
	// read and verify first deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader first deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on first entity";
	EXPECT_EQ(mKey1, key)
	<< "wrong key from ReadEntityHeader on first entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on first entity";

	// erroneously try to read first entity data
	char* dataBytes = new char[10];
	dataBytes[0] = 'A';
	EXPECT_EQ(NO_ERROR, reader->ReadEntityData(dataBytes, dataSize));
	// expect dataBytes to be unmodofied
	EXPECT_EQ('A', dataBytes[0]);

	// read and verify second deletion
	reader->ReadNextHeader(&done, &type);
	EXPECT_EQ(BACKUP_HEADER_ENTITY_V1, type)
	<< "wrong type from ReadNextHeader second deletion";

	EXPECT_EQ(NO_ERROR, reader->ReadEntityHeader(&key, &dataSize))
	<< "ReadEntityHeader returned an error on second entity";
	EXPECT_EQ(mKey2, key)
	<< "wrong key from ReadEntityHeader on second entity";
	EXPECT_EQ(-1, (int) dataSize)
	<< "not recognizing deletion on second entity";

	delete[] dataBytes;
	delete writer;
	delete reader;
	}

	}