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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 14:25:32 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 14:25:32 +0000
commit4e4f4b70c82887b4be905e55def870047fb0f4e7 (patch)
tree553f2f499192b3fa71f01f814120799aeab8a242 /mtester.h
parentInitial commit. (diff)
downloadlziprecover-3290bc7a8e8c653f309785a9dc997258effbab99.tar.xz
lziprecover-3290bc7a8e8c653f309785a9dc997258effbab99.zip
Adding upstream version 1.23.upstream/1.23upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'mtester.h')
-rw-r--r--mtester.h395
1 files changed, 395 insertions, 0 deletions
diff --git a/mtester.h b/mtester.h
new file mode 100644
index 0000000..12c7d2d
--- /dev/null
+++ b/mtester.h
@@ -0,0 +1,395 @@
+/* Lziprecover - Data recovery tool for the lzip format
+ Copyright (C) 2009-2022 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/>.
+*/
+
+class Range_mtester
+ {
+ const uint8_t * const buffer; // input buffer
+ const long long buffer_size;
+ long long pos; // current pos in buffer
+ uint32_t code;
+ uint32_t range;
+ bool at_stream_end;
+
+public:
+ Range_mtester( const uint8_t * const buf, const long long buf_size )
+ :
+ buffer( buf ),
+ buffer_size( buf_size ),
+ pos( Lzip_header::size ),
+ code( 0 ),
+ range( 0xFFFFFFFFU ),
+ at_stream_end( false )
+ {}
+
+ bool finished() { return pos >= buffer_size; }
+ unsigned long long member_position() const { return pos; }
+
+ uint8_t get_byte()
+ {
+ // 0xFF avoids decoder error if member is truncated at EOS marker
+ if( finished() ) return 0xFF;
+ return buffer[pos++];
+ }
+
+ const Lzip_trailer * get_trailer()
+ {
+ if( buffer_size - pos < Lzip_trailer::size ) return 0;
+ const Lzip_trailer * const p = (const Lzip_trailer *)( buffer + pos );
+ pos += Lzip_trailer::size;
+ return p;
+ }
+
+ void load()
+ {
+ code = 0;
+ for( int i = 0; i < 5; ++i ) code = ( code << 8 ) | get_byte();
+ range = 0xFFFFFFFFU;
+ code &= range; // make sure that first byte is discarded
+ }
+
+ void normalize()
+ {
+ if( range <= 0x00FFFFFFU )
+ { range <<= 8; code = ( code << 8 ) | get_byte(); }
+ }
+
+ unsigned decode( const int num_bits )
+ {
+ unsigned symbol = 0;
+ for( int i = num_bits; i > 0; --i )
+ {
+ normalize();
+ range >>= 1;
+// symbol <<= 1;
+// if( code >= range ) { code -= range; symbol |= 1; }
+ const bool bit = ( code >= range );
+ symbol <<= 1; symbol += bit;
+ code -= range & ( 0U - bit );
+ }
+ return symbol;
+ }
+
+ unsigned decode_bit( Bit_model & bm )
+ {
+ normalize();
+ const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
+ if( code < bound )
+ {
+ range = bound;
+ bm.probability +=
+ ( bit_model_total - bm.probability ) >> bit_model_move_bits;
+ return 0;
+ }
+ else
+ {
+ code -= bound;
+ range -= bound;
+ bm.probability -= bm.probability >> bit_model_move_bits;
+ return 1;
+ }
+ }
+
+ void decode_symbol_bit( Bit_model & bm, unsigned & symbol )
+ {
+ normalize();
+ symbol <<= 1;
+ const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
+ if( code < bound )
+ {
+ range = bound;
+ bm.probability +=
+ ( bit_model_total - bm.probability ) >> bit_model_move_bits;
+ }
+ else
+ {
+ code -= bound;
+ range -= bound;
+ bm.probability -= bm.probability >> bit_model_move_bits;
+ symbol |= 1;
+ }
+ }
+
+ void decode_symbol_bit_reversed( Bit_model & bm, unsigned & model,
+ unsigned & symbol, const int i )
+ {
+ normalize();
+ model <<= 1;
+ const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
+ if( code < bound )
+ {
+ range = bound;
+ bm.probability +=
+ ( bit_model_total - bm.probability ) >> bit_model_move_bits;
+ }
+ else
+ {
+ code -= bound;
+ range -= bound;
+ bm.probability -= bm.probability >> bit_model_move_bits;
+ model |= 1;
+ symbol |= 1 << i;
+ }
+ }
+
+ unsigned decode_tree6( Bit_model bm[] )
+ {
+ unsigned symbol = 1;
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ return symbol & 0x3F;
+ }
+
+ unsigned decode_tree8( Bit_model bm[] )
+ {
+ unsigned symbol = 1;
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ return symbol & 0xFF;
+ }
+
+ unsigned decode_tree_reversed( Bit_model bm[], const int num_bits )
+ {
+ unsigned model = 1;
+ unsigned symbol = 0;
+ for( int i = 0; i < num_bits; ++i )
+ decode_symbol_bit_reversed( bm[model], model, symbol, i );
+ return symbol;
+ }
+
+ unsigned decode_tree_reversed4( Bit_model bm[] )
+ {
+ unsigned model = 1;
+ unsigned symbol = 0;
+ decode_symbol_bit_reversed( bm[model], model, symbol, 0 );
+ decode_symbol_bit_reversed( bm[model], model, symbol, 1 );
+ decode_symbol_bit_reversed( bm[model], model, symbol, 2 );
+ decode_symbol_bit_reversed( bm[model], model, symbol, 3 );
+ return symbol;
+ }
+
+ unsigned decode_matched( Bit_model bm[], unsigned match_byte )
+ {
+ Bit_model * const bm1 = bm + 0x100;
+ unsigned symbol = 1;
+ while( symbol < 0x100 )
+ {
+ const unsigned match_bit = ( match_byte <<= 1 ) & 0x100;
+ const bool bit = decode_bit( bm1[symbol+match_bit] );
+ symbol <<= 1; symbol |= bit;
+ if( match_bit >> 8 != bit )
+ {
+ while( symbol < 0x100 ) decode_symbol_bit( bm[symbol], symbol );
+ break;
+ }
+ }
+ return symbol & 0xFF;
+ }
+
+ unsigned decode_len( Len_model & lm, const int pos_state )
+ {
+ Bit_model * bm;
+ unsigned mask, offset, symbol = 1;
+
+ if( decode_bit( lm.choice1 ) == 0 )
+ { bm = lm.bm_low[pos_state]; mask = 7; offset = 0; goto len3; }
+ if( decode_bit( lm.choice2 ) == 0 )
+ { bm = lm.bm_mid[pos_state]; mask = 7; offset = len_low_symbols; goto len3; }
+ bm = lm.bm_high; mask = 0xFF; offset = len_low_symbols + len_mid_symbols;
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+len3:
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ decode_symbol_bit( bm[symbol], symbol );
+ return ( symbol & mask ) + min_match_len + offset;
+ }
+ };
+
+class MD5SUM; // forward declaration
+
+class LZ_mtester
+ {
+ unsigned long long partial_data_pos;
+ Range_mtester rdec;
+ const unsigned dictionary_size;
+ uint8_t * buffer; // output buffer
+ unsigned pos; // current pos in buffer
+ unsigned stream_pos; // first byte not yet written to file
+ uint32_t crc_;
+ const int outfd; // output file descriptor
+ unsigned rep0; // rep[0-3] latest four distances
+ unsigned rep1; // used for efficient coding of
+ unsigned rep2; // repeated distances
+ unsigned rep3;
+ State state;
+ MD5SUM * const md5sum;
+ unsigned long long total_packets_; // total number of packets in member
+ unsigned long long max_rep0_pos; // file position of maximum distance
+ unsigned max_rep0; // maximum distance found
+ std::vector< unsigned long long > max_packet_posv_; // file pos of large packets
+ unsigned max_packet_size_; // maximum packet size found
+ unsigned max_marker_size_; // maximum marker size found
+ bool pos_wrapped;
+ bool buffer_is_external;
+
+ Bit_model bm_literal[1<<literal_context_bits][0x300];
+ Bit_model bm_match[State::states][pos_states];
+ Bit_model bm_rep[State::states];
+ Bit_model bm_rep0[State::states];
+ Bit_model bm_rep1[State::states];
+ Bit_model bm_rep2[State::states];
+ Bit_model bm_len[State::states][pos_states];
+ Bit_model bm_dis_slot[len_states][1<<dis_slot_bits];
+ Bit_model bm_dis[modeled_distances-end_dis_model+1];
+ Bit_model bm_align[dis_align_size];
+
+ Len_model match_len_model;
+ Len_model rep_len_model;
+
+ void print_block( const int len );
+ void flush_data();
+ bool verify_trailer( FILE * const f = 0, unsigned long long byte_pos = 0 );
+
+ uint8_t peek_prev() const
+ { return buffer[((pos > 0) ? pos : dictionary_size)-1]; }
+
+ uint8_t peek( const unsigned distance ) const
+ {
+ const unsigned i = ( ( pos > distance ) ? 0 : dictionary_size ) +
+ pos - distance - 1;
+ return buffer[i];
+ }
+
+ void put_byte( const uint8_t b )
+ {
+ buffer[pos] = b;
+ if( ++pos >= dictionary_size ) flush_data();
+ }
+
+ void copy_block( const unsigned distance, unsigned len )
+ {
+ unsigned lpos = pos, i = lpos - distance - 1;
+ bool fast, fast2;
+ if( lpos > distance )
+ {
+ fast = ( len < dictionary_size - lpos );
+ fast2 = ( fast && len <= lpos - i );
+ }
+ else
+ {
+ i += dictionary_size;
+ fast = ( len < dictionary_size - i ); // (i == pos) may happen
+ fast2 = ( fast && len <= i - lpos );
+ }
+ if( fast ) // no wrap
+ {
+ pos += len;
+ if( fast2 ) // no wrap, no overlap
+ std::memcpy( buffer + lpos, buffer + i, len );
+ else
+ for( ; len > 0; --len ) buffer[lpos++] = buffer[i++];
+ }
+ else for( ; len > 0; --len )
+ {
+ buffer[pos] = buffer[i];
+ if( ++pos >= dictionary_size ) flush_data();
+ if( ++i >= dictionary_size ) i = 0;
+ }
+ }
+
+void set_max_packet( const unsigned new_size, const unsigned long long pos )
+ {
+ if( max_packet_size_ > new_size || new_size == 0 ) return;
+ if( max_packet_size_ < new_size ) // new max size
+ { max_packet_size_ = new_size; max_packet_posv_.clear(); }
+ max_packet_posv_.push_back( pos - new_size ); // pos of first byte
+ }
+
+void set_max_marker( const unsigned new_size )
+ { if( max_marker_size_ < new_size ) max_marker_size_ = new_size; }
+
+public:
+ LZ_mtester( const uint8_t * const ibuf, const long long ibuf_size,
+ const unsigned dict_size, const int ofd = -1,
+ MD5SUM * const md5sum_ = 0 )
+ :
+ partial_data_pos( 0 ),
+ rdec( ibuf, ibuf_size ),
+ dictionary_size( dict_size ),
+ buffer( new uint8_t[dictionary_size] ),
+ pos( 0 ),
+ stream_pos( 0 ),
+ crc_( 0xFFFFFFFFU ),
+ outfd( ofd ),
+ rep0( 0 ),
+ rep1( 0 ),
+ rep2( 0 ),
+ rep3( 0 ),
+ md5sum( md5sum_ ),
+ total_packets_( -1ULL ), // don't count EOS marker
+ max_rep0_pos( 0 ),
+ max_rep0( 0 ),
+ max_packet_size_( 0 ),
+ max_marker_size_( 0 ),
+ pos_wrapped( false ), buffer_is_external( false )
+ // prev_byte of first byte; also for peek( 0 ) on corrupt file
+ { buffer[dictionary_size-1] = 0; }
+
+ ~LZ_mtester() { if( !buffer_is_external ) delete[] buffer; }
+
+ unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; }
+ unsigned long long data_position() const { return partial_data_pos + pos; }
+ bool finished() { return rdec.finished(); }
+ unsigned long long member_position() const { return rdec.member_position(); }
+ unsigned long long total_packets() const { return total_packets_; }
+ unsigned long long max_distance_pos() const { return max_rep0_pos; }
+ unsigned max_distance() const { return max_rep0 + 1; }
+ const std::vector< unsigned long long > & max_packet_posv() const
+ { return max_packet_posv_; }
+ unsigned max_packet_size() const { return max_packet_size_; }
+ unsigned max_marker_size() const { return max_marker_size_; }
+
+ const uint8_t * get_buffers( const uint8_t ** const prev_bufferp,
+ int * const sizep, int * const prev_sizep ) const
+ { *sizep = ( pos_wrapped && pos == 0 ) ? dictionary_size : pos;
+ *prev_sizep = ( pos_wrapped && pos > 0 ) ? dictionary_size - pos : 0;
+ *prev_bufferp = buffer + pos; return buffer; }
+
+ void duplicate_buffer( uint8_t * const buffer2 );
+
+ // these two functions set max_rep0
+ int test_member( const unsigned long long mpos_limit = LLONG_MAX,
+ const unsigned long long dpos_limit = LLONG_MAX,
+ FILE * const f = 0, const unsigned long long byte_pos = 0 );
+ /* this function also sets max_rep0_pos, total_packets_, max_packet_size_,
+ max_packet_posv_, and max_marker_size_ */
+ int debug_decode_member( const long long dpos, const long long mpos,
+ const bool show_packets );
+ };