Merging upstream version 1.16~pre2.

Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>

1 files changed, 300 insertions, 0 deletions

diff --git a/mtester.h b/mtester.h
new file mode 100644
index 0000000..3ff3fcb
--- /dev/null
+++ b/mtester.h
@@ -0,0 +1,300 @@
+/*  Lziprecover - Data recovery tool for lzip files
+    Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014 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 3 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 buffer_size;
+  long pos;			// current pos in buffer
+  uint32_t code;
+  uint32_t range;
+  bool at_stream_end;
+
+  void operator=( const Range_mtester & );	// declared as private
+
+public:
+  Range_mtester( const uint8_t * const buf, const long buf_size )
+    :
+    buffer( buf ),
+    buffer_size( buf_size ),
+    pos( File_header::size ),
+    code( 0 ),
+    range( 0xFFFFFFFFU ),
+    at_stream_end( false )
+    {}
+
+  void load()
+    {
+    for( int i = 0; i < 5; ++i ) code = (code << 8) | get_byte();
+    code &= range;		// make sure that first byte is discarded
+    }
+
+  bool code_is_zero() const { return ( code == 0 ); }
+  bool finished() { return pos >= buffer_size; }
+  long member_position() const { return pos; }
+
+  const File_trailer * get_trailer()
+    {
+    if( buffer_size - pos < File_trailer::size ) return 0;
+    const File_trailer * const p = (File_trailer *)(buffer + pos);
+    pos += File_trailer::size;
+    return p;
+    }
+
+  uint8_t get_byte()
+    {
+    if( finished() ) return 0xAA;		// make code != 0
+    return buffer[pos++];
+    }
+
+  void normalize()
+    {
+    if( range <= 0x00FFFFFFU )
+      { range <<= 8; code = (code << 8) | get_byte(); }
+    }
+
+  int decode( const int num_bits )
+    {
+    int symbol = 0;
+    for( int i = num_bits; i > 0; --i )
+      {
+      normalize();
+      range >>= 1;
+//      symbol <<= 1;
+//      if( code >= range ) { code -= range; symbol |= 1; }
+      const uint32_t mask = 0U - (code < range);
+      code -= range;
+      code += range & mask;
+      symbol = (symbol << 1) + (mask + 1);
+      }
+    return symbol;
+    }
+
+  int 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
+      {
+      range -= bound;
+      code -= bound;
+      bm.probability -= bm.probability >> bit_model_move_bits;
+      return 1;
+      }
+    }
+
+  int decode_tree3( Bit_model bm[] )
+    {
+    int symbol = 1;
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    return symbol & 7;
+    }
+
+  int decode_tree6( Bit_model bm[] )
+    {
+    int symbol = 1;
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    return symbol & 0x3F;
+    }
+
+  int decode_tree8( Bit_model bm[] )
+    {
+    int symbol = 1;
+    while( symbol < 0x100 )
+      symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+    return symbol & 0xFF;
+    }
+
+  int decode_tree_reversed( Bit_model bm[], const int num_bits )
+    {
+    int model = 1;
+    int symbol = 0;
+    for( int i = 0; i < num_bits; ++i )
+      {
+      const bool bit = decode_bit( bm[model] );
+      model <<= 1;
+      if( bit ) { ++model; symbol |= (1 << i); }
+      }
+    return symbol;
+    }
+
+  int decode_tree_reversed4( Bit_model bm[] )
+    {
+    int model = 1;
+    int symbol = decode_bit( bm[model] );
+    model = (model << 1) + symbol;
+    int bit = decode_bit( bm[model] );
+    model = (model << 1) + bit; symbol |= (bit << 1);
+    bit = decode_bit( bm[model] );
+    model = (model << 1) + bit; symbol |= (bit << 2);
+    if( decode_bit( bm[model] ) ) symbol |= 8;
+    return symbol;
+    }
+
+  int decode_matched( Bit_model bm[], int match_byte )
+    {
+    Bit_model * const bm1 = bm + 0x100;
+    int symbol = 1;
+    while( symbol < 0x100 )
+      {
+      match_byte <<= 1;
+      const int match_bit = match_byte & 0x100;
+      const int bit = decode_bit( bm1[match_bit+symbol] );
+      symbol = ( symbol << 1 ) | bit;
+      if( match_bit != bit << 8 )
+        {
+        while( symbol < 0x100 )
+          symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
+        break;
+        }
+      }
+    return symbol & 0xFF;
+    }
+
+  int decode_len( Len_model & lm, const int pos_state )
+    {
+    if( decode_bit( lm.choice1 ) == 0 )
+      return decode_tree3( lm.bm_low[pos_state] );
+    if( decode_bit( lm.choice2 ) == 0 )
+      return len_low_symbols + decode_tree3( lm.bm_mid[pos_state] );
+    return len_low_symbols + len_mid_symbols + decode_tree8( lm.bm_high );
+    }
+  };
+
+
+class LZ_mtester
+  {
+  unsigned long long partial_data_pos;
+  Range_mtester rdec;
+  const unsigned dictionary_size;
+  const int buffer_size;
+  uint8_t * buffer;		// output buffer
+  int pos;			// current pos in buffer
+  int stream_pos;		// first byte not yet written to file
+  uint32_t crc_;
+  unsigned rep0;		// rep[0-3] latest four distances
+  unsigned rep1;		// used for efficient coding of
+  unsigned rep2;		// repeated distances
+  unsigned rep3;
+  State state;
+
+  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];
+  Bit_model bm_align[dis_align_size];
+
+  Len_model match_len_model;
+  Len_model rep_len_model;
+
+  unsigned long long stream_position() const
+    { return partial_data_pos + stream_pos; }
+  void flush_data();
+  bool verify_trailer();
+
+  uint8_t get_prev_byte() const
+    {
+    const int i = ( ( pos > 0 ) ? pos : buffer_size ) - 1;
+    return buffer[i];
+    }
+
+  uint8_t get_byte( const int distance ) const
+    {
+    int i = pos - distance - 1;
+    if( i < 0 ) i += buffer_size;
+    return buffer[i];
+    }
+
+  void put_byte( const uint8_t b )
+    {
+    buffer[pos] = b;
+    if( ++pos >= buffer_size ) flush_data();
+    }
+
+  void copy_block( const int distance, int len )
+    {
+    int i = pos - distance - 1;
+    if( i < 0 ) i += buffer_size;
+    if( len < buffer_size - std::max( pos, i ) && len <= std::abs( pos - i ) )
+      {
+      std::memcpy( buffer + pos, buffer + i, len );	// no wrap, no overlap
+      pos += len;
+      }
+    else for( ; len > 0; --len )
+      {
+      buffer[pos] = buffer[i];
+      if( ++pos >= buffer_size ) flush_data();
+      if( ++i >= buffer_size ) i = 0;
+      }
+    }
+
+  void operator=( const LZ_mtester & );		// declared as private
+
+public:
+  LZ_mtester( const uint8_t * const ibuf, const long ibuf_size,
+              const int dict_size )
+    :
+    partial_data_pos( 0 ),
+    rdec( ibuf, ibuf_size ),
+    dictionary_size( dict_size ),
+    buffer_size( std::max( 65536U, dictionary_size ) ),
+    buffer( new uint8_t[buffer_size] ),
+    pos( 0 ),
+    stream_pos( 0 ),
+    crc_( 0xFFFFFFFFU ),
+    rep0( 0 ),
+    rep1( 0 ),
+    rep2( 0 ),
+    rep3( 0 )
+    { buffer[buffer_size-1] = 0; }	// prev_byte of first byte
+
+  ~LZ_mtester() { delete[] buffer; }
+
+  unsigned crc() const { return crc_ ^ 0xFFFFFFFFU; }
+  unsigned long long data_position() const { return partial_data_pos + pos; }
+  bool finished() { return rdec.finished(); }
+  long member_position() const { return rdec.member_position(); }
+
+  void duplicate_buffer();
+  int test_member( const long pos_limit = LONG_MAX );
+  };
+
+
+uint8_t * read_member( const int infd, const long long mpos,
+                       const long long msize );
+const LZ_mtester * prepare_master( const uint8_t * const buffer,
+                                   const long buffer_size,
+                                   const long pos_limit );
+bool test_member_rest( const LZ_mtester & master, long * const failure_posp = 0 );