lzip/lzip_index.h

94 lines
3.1 KiB
C++

/* Lzip - LZMA lossless data compressor
Copyright (C) 2008-2024 Antonio Diaz Diaz.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef INT64_MAX
#define INT64_MAX 0x7FFFFFFFFFFFFFFFLL
#endif
class Block
{
long long pos_, size_; // pos >= 0, size >= 0, pos + size <= INT64_MAX
public:
Block( const long long p, const long long s ) : pos_( p ), size_( s ) {}
long long pos() const { return pos_; }
long long size() const { return size_; }
long long end() const { return pos_ + size_; }
void pos( const long long p ) { pos_ = p; }
void size( const long long s ) { size_ = s; }
};
class Lzip_index
{
struct Member
{
Block dblock, mblock; // data block, member block
unsigned dictionary_size;
Member( const long long dpos, const long long dsize,
const long long mpos, const long long msize,
const unsigned dict_size )
: dblock( dpos, dsize ), mblock( mpos, msize ),
dictionary_size( dict_size ) {}
};
std::vector< Member > member_vector;
std::string error_;
const long long insize;
int retval_;
unsigned dictionary_size_; // largest dictionary size in the file
bool check_header( const Lzip_header & header );
void set_errno_error( const char * const msg );
void set_num_error( const char * const msg, unsigned long long num );
bool read_header( const int fd, Lzip_header & header, const long long pos,
const bool ignore_marking );
bool skip_trailing_data( const int fd, unsigned long long & pos,
const Cl_options & cl_opts );
public:
Lzip_index( const int infd, const Cl_options & cl_opts );
long members() const { return member_vector.size(); }
const std::string & error() const { return error_; }
int retval() const { return retval_; }
unsigned dictionary_size() const { return dictionary_size_; }
long long udata_size() const
{ if( member_vector.empty() ) return 0;
return member_vector.back().dblock.end(); }
long long cdata_size() const
{ if( member_vector.empty() ) return 0;
return member_vector.back().mblock.end(); }
// total size including trailing data (if any)
long long file_size() const
{ if( insize >= 0 ) return insize; else return 0; }
const Block & dblock( const long i ) const
{ return member_vector[i].dblock; }
const Block & mblock( const long i ) const
{ return member_vector[i].mblock; }
unsigned dictionary_size( const long i ) const
{ return member_vector[i].dictionary_size; }
};