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#ifndef PACKAGE_H
#define PACKAGE_H
#define USE_ZLIB
#include <string>
#include <map>
#include <vector>
#ifdef USE_ZLIB
#include <zlib.h>
#endif
#define MAX_CHUNK_NAME_LENGTH 255
typedef uint32_t plen_t;
class package;
class chunk_writer
{
private:
package *pkg;
string name;
plen_t first_block;
plen_t cur_block;
plen_t block_len;
#ifdef USE_ZLIB
z_stream zs;
Bytef *z_buffer;
#endif
void raw_write(const void *data, plen_t len);
void finish_block(plen_t next);
public:
chunk_writer(package *parent, const string _name);
~chunk_writer();
void write(const void *data, plen_t len);
friend class package;
};
class chunk_reader
{
private:
chunk_reader(package *parent, plen_t start);
void init(plen_t start);
package *pkg;
plen_t first_block, next_block;
plen_t off, block_left;
#ifdef USE_ZLIB
bool eof;
z_stream zs;
Bytef z_buffer[32768];
#endif
plen_t raw_read(void *data, plen_t len);
public:
chunk_reader(package *parent, const string _name);
~chunk_reader();
plen_t read(void *data, plen_t len);
void read_all(vector<char> &data);
friend class package;
};
class package
{
public:
package(const char* file, bool writeable, bool empty = false);
package();
~package();
chunk_writer* writer(const string name);
chunk_reader* reader(const string name);
void commit();
void delete_chunk(const string name);
bool has_chunk(const string name);
vector<string> list_chunks();
void abort();
void unlink();
// statistics
plen_t get_slack();
plen_t get_size() const { return file_len; };
plen_t get_chunk_fragmentation(const string name);
plen_t get_chunk_compressed_length(const string name);
private:
string filename;
bool rw;
int fd;
plen_t file_len;
int n_users;
bool dirty;
bool aborted;
bool tmp;
map<string, plen_t> directory;
map<plen_t, plen_t> free_blocks;
vector<plen_t> unlinked_blocks;
map<plen_t, pair<plen_t, plen_t> > block_map;
set<plen_t> new_chunks;
map<plen_t, uint32_t> reader_count;
plen_t extend_block(plen_t at, plen_t size, plen_t by);
plen_t alloc_block(plen_t &size);
void finish_chunk(const string name, plen_t at);
void free_chunk(const string name);
plen_t write_directory();
void collect_blocks();
void free_block_chain(plen_t at);
void free_block(plen_t at, plen_t size);
void seek(plen_t to);
void fsck();
void read_directory(plen_t start, uint8_t version);
void trace_chunk(plen_t start);
void load();
void load_traces();
friend class chunk_writer;
friend class chunk_reader;
};
#endif
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