replicant-frameworks_native/include/utils/BackupHelpers.h
Joe Onorato 9cda3e02c6 Helper API cleanup. Allows multiple helpers to function,
because they'll always go in the same order, and this lets
us not have to write headers to keep them paired.
2009-06-22 13:02:24 -07:00

157 lines
3.6 KiB
C++

/*
* Copyright (C) 2009 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.
*/
#ifndef _UTILS_BACKUP_HELPERS_H
#define _UTILS_BACKUP_HELPERS_H
#include <utils/Errors.h>
#include <utils/String8.h>
#include <utils/KeyedVector.h>
namespace android {
enum {
BACKUP_HEADER_ENTITY_V1 = 0x61746144, // Data (little endian)
};
typedef struct {
int type; // BACKUP_HEADER_ENTITY_V1
int keyLen; // length of the key name, not including the null terminator
int dataSize; // size of the data, not including the padding, -1 means delete
} entity_header_v1;
struct SnapshotHeader {
int magic0;
int fileCount;
int magic1;
int totalSize;
};
struct FileState {
int modTime_sec;
int modTime_nsec;
int size;
int crc32;
int nameLen;
};
struct FileRec {
String8 file;
bool deleted;
FileState s;
};
/**
* Writes the data.
*
* If an error occurs, it poisons this object and all write calls will fail
* with the error that occurred.
*/
class BackupDataWriter
{
public:
BackupDataWriter(int fd);
// does not close fd
~BackupDataWriter();
status_t WriteEntityHeader(const String8& key, size_t dataSize);
status_t WriteEntityData(const void* data, size_t size);
void SetKeyPrefix(const String8& keyPrefix);
private:
explicit BackupDataWriter();
status_t write_padding_for(int n);
int m_fd;
status_t m_status;
ssize_t m_pos;
int m_entityCount;
String8 m_keyPrefix;
};
/**
* Reads the data.
*
* If an error occurs, it poisons this object and all write calls will fail
* with the error that occurred.
*/
class BackupDataReader
{
public:
BackupDataReader(int fd);
// does not close fd
~BackupDataReader();
status_t Status();
status_t ReadNextHeader(bool* done, int* type);
bool HasEntities();
status_t ReadEntityHeader(String8* key, size_t* dataSize);
status_t SkipEntityData(); // must be called with the pointer at the begining of the data.
ssize_t ReadEntityData(void* data, size_t size);
private:
explicit BackupDataReader();
status_t skip_padding();
int m_fd;
bool m_done;
status_t m_status;
ssize_t m_pos;
ssize_t m_dataEndPos;
int m_entityCount;
union {
int type;
entity_header_v1 entity;
} m_header;
String8 m_key;
};
int back_up_files(int oldSnapshotFD, BackupDataWriter* dataStream, int newSnapshotFD,
char const* const* files, char const* const *keys, int fileCount);
class RestoreHelperBase
{
public:
RestoreHelperBase();
~RestoreHelperBase();
status_t WriteFile(const String8& filename, BackupDataReader* in);
status_t WriteSnapshot(int fd);
private:
void* m_buf;
KeyedVector<String8,FileRec> m_files;
};
#define TEST_BACKUP_HELPERS 1
#if TEST_BACKUP_HELPERS
int backup_helper_test_empty();
int backup_helper_test_four();
int backup_helper_test_files();
int backup_helper_test_null_base();
int backup_helper_test_missing_file();
int backup_helper_test_data_writer();
int backup_helper_test_data_reader();
#endif
} // namespace android
#endif // _UTILS_BACKUP_HELPERS_H