Adding upstream version 0.3.upstream/0.3

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

1 files changed, 608 insertions, 0 deletions

diff --git a/encoder.h b/encoder.h
new file mode 100644
index 0000000..af8c441
--- /dev/null
+++ b/encoder.h
@@ -0,0 +1,608 @@
+/*  Lzlib - A compression library for lzip files
+    Copyright (C) 2009 Antonio Diaz Diaz.
+
+    This library 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 library 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/>.
+
+    As a special exception, you may use this file as part of a free
+    software library without restriction.  Specifically, if other files
+    instantiate templates or use macros or inline functions from this
+    file, or you compile this file and link it with other files to
+    produce an executable, this file does not by itself cause the
+    resulting executable to be covered by the GNU General Public
+    License.  This exception does not however invalidate any other
+    reasons why the executable file might be covered by the GNU General
+    Public License.
+*/
+
+const int max_num_trials = 1 << 12;
+const int price_shift = 6;
+
+class Dis_slots
+  {
+  unsigned char data[1<<12];
+
+public:
+  Dis_slots()
+    {
+    for( int slot = 0; slot < 4; ++slot ) data[slot] = slot;
+    for( int i = 4, size = 2, slot = 4; slot < 24; slot += 2 )
+      {
+      std::memset( &data[i], slot, size );
+      std::memset( &data[i+size], slot + 1, size );
+      size <<= 1;
+      i += size;
+      }
+    }
+
+  int operator[]( const uint32_t dis ) const throw()
+    {
+    if( dis < (1 << 12) ) return data[dis];
+    if( dis < (1 << 23) ) return data[dis>>11] + 22;
+    return data[dis>>22] + 44;
+    }
+  };
+
+extern const Dis_slots dis_slots;
+
+class Prob_prices
+  {
+  int data[bit_model_total >> 2];
+
+public:
+  Prob_prices()
+    {
+    const int num_bits = ( bit_model_total_bits - 2 );
+    for( int i = num_bits - 1; i >= 0; --i )
+      {
+      int start = 1 << ( num_bits - i - 1 );
+      int end = 1 << ( num_bits - i);
+      for( int j = start; j < end; ++j )
+        data[j] = (i << price_shift) +
+            ( ((end - j) << price_shift) >> (num_bits - i - 1) );
+      }
+    }
+
+  int operator[]( const int symbol ) const throw()
+    { return data[symbol >> 2]; }
+  };
+
+extern const Prob_prices prob_prices;
+
+inline int price0( const Bit_model & bm ) throw()
+  { return prob_prices[bm.probability]; }
+
+inline int price1( const Bit_model & bm ) throw()
+  { return prob_prices[bit_model_total-bm.probability]; }
+
+inline int price_bit( const Bit_model & bm, const int bit ) throw()
+  { if( bit ) return price1( bm ); else return price0( bm ); }
+
+inline int price_symbol( const Bit_model bm[], int symbol, const int num_bits ) throw()
+  {
+  symbol |= ( 1 << num_bits );
+  int price = 0;
+  while( symbol > 1 )
+    {
+    const int bit = symbol & 1;
+    symbol >>= 1;
+    price += price_bit( bm[symbol-1], bit );
+    }
+  return price;
+  }
+
+inline int price_symbol_reversed( const Bit_model bm[], int symbol,
+                                  const int num_bits ) throw()
+  {
+  int price = 0;
+  int model = 1;
+  for( int i = num_bits; i > 0; --i )
+    {
+    const int bit = symbol & 1;
+    symbol >>= 1;
+    price += price_bit( bm[model-1], bit );
+    model = ( model << 1 ) | bit;
+    }
+  return price;
+  }
+
+inline int price_matched( const Bit_model bm[], const int symbol,
+                          const int match_byte ) throw()
+  {
+  int price = 0;
+  int model = 1;
+
+  for( int i = 7; i >= 0; --i )
+    {
+    const int match_bit = ( match_byte >> i ) & 1;
+    const int bit = ( symbol >> i ) & 1;
+    price += price_bit( bm[(match_bit<<8)+model+0xFF], bit );
+    model = ( model << 1 ) | bit;
+    if( match_bit != bit )
+      {
+      while( --i >= 0 )
+        {
+        const int bit = ( symbol >> i ) & 1;
+        price += price_bit( bm[model-1], bit );
+        model = ( model << 1 ) | bit;
+        }
+      break;
+      }
+    }
+  return price;
+  }
+
+
+class Matchfinder
+  {
+  enum { num_prev_positions4 = 1 << 20,
+         num_prev_positions3 = 1 << 18,
+         num_prev_positions2 = 1 << 16,
+         num_prev_positions = num_prev_positions4 + num_prev_positions3 +
+                              num_prev_positions2 };
+
+  long long partial_data_pos;
+  const int dictionary_size_;	// bytes to keep in buffer before pos
+  const int after_size;		// bytes to keep in buffer after pos
+  const int buffer_size;
+  uint8_t * const buffer;
+  int pos;
+  int cyclic_pos;
+  int stream_pos;		// first byte not yet read from file
+  const int pos_limit;		// when reached, a new block must be read
+  const int match_len_limit_;
+  int32_t * const prev_positions;	// last seen position of key
+  int32_t * prev_pos_tree;
+  bool at_stream_end_;		// stream_pos shows real end of file
+
+public:
+  Matchfinder( const int dict_size, const int len_limit )
+    :
+    partial_data_pos( 0 ),
+    dictionary_size_( dict_size ),
+    after_size( max_num_trials + max_match_len ),
+    buffer_size( ( 2 * std::max( 65536, dictionary_size_ ) ) +
+                 max_num_trials + after_size ),
+    buffer( new( std::nothrow ) uint8_t[buffer_size] ),
+    pos( 0 ),
+    cyclic_pos( 0 ),
+    stream_pos( 0 ),
+    pos_limit( buffer_size - after_size ),
+    match_len_limit_( len_limit ),
+    prev_positions( new( std::nothrow ) int32_t[num_prev_positions] ),
+    at_stream_end_( false )
+    {
+    prev_pos_tree = new( std::nothrow ) int32_t[2*dictionary_size_];
+    if( !buffer || !prev_positions || !prev_pos_tree )
+      {
+      if( prev_pos_tree ) delete[] prev_pos_tree;
+      if( prev_positions ) delete[] prev_positions;
+      if( buffer ) delete[] buffer;
+      throw std::bad_alloc();
+      }
+    for( int i = 0; i < num_prev_positions; ++i ) prev_positions[i] = -1;
+    }
+
+  ~Matchfinder()
+    { delete[] prev_pos_tree; delete[] prev_positions; delete[] buffer; }
+
+  uint8_t operator[]( const int i ) const throw() { return buffer[pos+i]; }
+  bool at_stream_end() const throw() { return at_stream_end_; }
+  int available_bytes() const throw() { return stream_pos - pos; }
+  long long data_position() const throw() { return partial_data_pos + pos; }
+  int dictionary_size() const throw() { return dictionary_size_; }
+  void finish() throw() { at_stream_end_ = true; }
+  bool finished() const throw() { return at_stream_end_ && pos >= stream_pos; }
+  int match_len_limit() const throw() { return match_len_limit_; }
+  const uint8_t * ptr_to_current_pos() const throw() { return buffer + pos; }
+
+  bool dec_pos( const int ahead ) throw()
+    {
+    if( ahead < 0 || pos < ahead ) return false;
+    pos -= ahead;
+    cyclic_pos -= ahead;
+    if( cyclic_pos < 0 ) cyclic_pos += dictionary_size_;
+    return true;
+    }
+
+  int true_match_len( const int index, const int distance, int len_limit ) const throw()
+    {
+    if( index + len_limit > available_bytes() )
+      len_limit = available_bytes() - index;
+    const uint8_t * const data = buffer + pos + index - distance;
+    int i = 0;
+    while( i < len_limit && data[i] == data[i+distance] ) ++i;
+    return i;
+    }
+
+  int write_data( uint8_t * const in_buffer, const int in_size ) throw();
+  bool reset() throw();
+  bool move_pos() throw();
+  int longest_match_len( int * const distances = 0 ) throw();
+  };
+
+
+class Range_encoder : public Circular_buffer
+  {
+  uint64_t low;
+  long long partial_member_pos;
+  uint32_t range;
+  int ff_count;
+  uint8_t cache;
+
+  void shift_low()
+    {
+    const uint32_t carry = low >> 32;
+    if( low < 0xFF000000 || carry == 1 )
+      {
+      put_byte( cache + carry );
+      for( ; ff_count > 0; --ff_count ) put_byte( 0xFF + carry );
+      cache = low >> 24;
+      }
+    else ++ff_count;
+    low = ( low & 0x00FFFFFF ) << 8;
+    }
+
+public:
+  Range_encoder()
+    :
+    Circular_buffer( 65536 + (2 * max_num_trials) ),
+    low( 0 ),
+    partial_member_pos( 0 ),
+    range( 0xFFFFFFFF ),
+    ff_count( 0 ),
+    cache( 0 ) {}
+
+  int read_data( uint8_t * const out_buffer, const int out_size ) throw()
+    {
+    const int size = Circular_buffer::read_data( out_buffer, out_size );
+    if( size > 0 ) partial_member_pos += size;
+    return size;
+    }
+
+  void flush() { for( int i = 0; i < 5; ++i ) shift_low(); }
+
+  long long member_position() const throw()
+    { return partial_member_pos + used_bytes() + ff_count; }
+
+  void encode( const int symbol, const int num_bits )
+    {
+    for( int i = num_bits - 1; i >= 0; --i )
+      {
+      range >>= 1;
+      if( (symbol >> i) & 1 ) low += range;
+      if( range <= 0x00FFFFFF ) { range <<= 8; shift_low(); }
+      }
+    }
+
+  void encode_bit( Bit_model & bm, const int bit )
+    {
+    const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability;
+    if( !bit )
+      {
+      range = bound;
+      bm.probability += (bit_model_total - bm.probability) >> bit_model_move_bits;
+      }
+    else
+      {
+      low += bound;
+      range -= bound;
+      bm.probability -= bm.probability >> bit_model_move_bits;
+      }
+    if( range <= 0x00FFFFFF ) { range <<= 8; shift_low(); }
+    }
+
+  void encode_tree( Bit_model bm[], const int symbol, const int num_bits )
+    {
+    int mask = ( 1 << ( num_bits - 1 ) );
+    int model = 1;
+    for( int i = num_bits; i > 0; --i, mask >>= 1 )
+      {
+      const int bit = ( symbol & mask );
+      encode_bit( bm[model-1], bit );
+      model <<= 1;
+      if( bit ) model |= 1;
+      }
+    }
+
+  void encode_tree_reversed( Bit_model bm[], int symbol, const int num_bits )
+    {
+    int model = 1;
+    for( int i = num_bits; i > 0; --i )
+      {
+      const int bit = symbol & 1;
+      encode_bit( bm[model-1], bit );
+      model = ( model << 1 ) | bit;
+      symbol >>= 1;
+      }
+    }
+
+  void encode_matched( Bit_model bm[], int symbol, int match_byte )
+    {
+    int model = 1;
+    for( int i = 7; i >= 0; --i )
+      {
+      const int bit = ( symbol >> i ) & 1;
+      const int match_bit = ( match_byte >> i ) & 1;
+      encode_bit( bm[(match_bit<<8)+model+0xFF], bit );
+      model = ( model << 1 ) | bit;
+      if( match_bit != bit )
+        {
+        while( --i >= 0 )
+          {
+          const int bit = ( symbol >> i ) & 1;
+          encode_bit( bm[model-1], bit );
+          model = ( model << 1 ) | bit;
+          }
+        break;
+        }
+      }
+    }
+  };
+
+
+class Len_encoder
+  {
+  Bit_model choice1;
+  Bit_model choice2;
+  Bit_model bm_low[pos_states][len_low_symbols];
+  Bit_model bm_mid[pos_states][len_mid_symbols];
+  Bit_model bm_high[len_high_symbols];
+  int prices[pos_states][max_len_symbols];
+  const int len_symbols;
+  int counters[pos_states];
+
+  void update_prices( const int pos_state ) throw()
+    {
+    int * const pps = prices[pos_state];
+    int price = price0( choice1 );
+    int len = 0;
+    for( ; len < len_low_symbols && len < len_symbols; ++len )
+      pps[len] = price +
+                 price_symbol( bm_low[pos_state], len, len_low_bits );
+    price = price1( choice1 );
+    for( ; len < len_low_symbols + len_mid_symbols && len < len_symbols; ++len )
+      pps[len] = price + price0( choice2 ) +
+                 price_symbol( bm_mid[pos_state], len - len_low_symbols, len_mid_bits );
+    for( ; len < len_symbols; ++len )
+      pps[len] = price + price1( choice2 ) +
+                 price_symbol( bm_high, len - len_low_symbols - len_mid_symbols, len_high_bits );
+    counters[pos_state] = len_symbols;
+    }
+
+public:
+  Len_encoder( const int len_limit )
+    : len_symbols( len_limit + 1 - min_match_len )
+    {
+    for( int i = 0; i < pos_states; ++i ) update_prices( i );
+    }
+
+  void encode( Range_encoder & range_encoder, int symbol,
+               const int pos_state );
+
+  int price( const int symbol, const int pos_state ) const throw()
+    { return prices[pos_state][symbol - min_match_len]; }
+  };
+
+
+class Literal_encoder
+  {
+  Bit_model bm_literal[1<<literal_context_bits][0x300];
+
+  int state( const int prev_byte ) const throw()
+    { return ( prev_byte >> ( 8 - literal_context_bits ) ); }
+
+public:
+  void encode( Range_encoder & range_encoder, uint8_t prev_byte, uint8_t symbol )
+    { range_encoder.encode_tree( bm_literal[state(prev_byte)], symbol, 8 ); }
+
+  void encode_matched( Range_encoder & range_encoder, uint8_t prev_byte, uint8_t match_byte, uint8_t symbol )
+    { range_encoder.encode_matched( bm_literal[state(prev_byte)], symbol, match_byte ); }
+
+  int price_matched( uint8_t prev_byte, uint8_t symbol, uint8_t match_byte ) const throw()
+    { return ::price_matched( bm_literal[state(prev_byte)], symbol, match_byte ); }
+
+  int price_symbol( uint8_t prev_byte, uint8_t symbol ) const throw()
+    { return ::price_symbol( bm_literal[state(prev_byte)], symbol, 8 ); }
+  };
+
+
+class LZ_encoder
+  {
+  enum { dis_align_mask = dis_align_size - 1,
+         infinite_price = 0x0FFFFFFF,
+         num_rep_distances = 4 };	// must be 4
+
+  struct Trial
+    {
+    State state;
+    int dis;
+    int prev_index;
+    int price;		// dual use var; cumulative price, match length
+    int reps[num_rep_distances];
+    void update( const int d, const int p_i, const int pr ) throw()
+      { if( pr < price ) { dis = d; prev_index = p_i; price = pr; } }
+    };
+
+  const long long member_size_limit;
+  int longest_match_found;
+  uint32_t crc_;
+
+  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[max_dis_states][1<<dis_slot_bits];
+  Bit_model bm_dis[modeled_distances-end_dis_model];
+  Bit_model bm_align[dis_align_size];
+
+  Matchfinder & matchfinder;
+  Range_encoder range_encoder;
+  Len_encoder len_encoder;
+  Len_encoder rep_match_len_encoder;
+  Literal_encoder literal_encoder;
+
+  const int num_dis_slots;
+  int rep_distances[num_rep_distances];
+  int match_distances[max_match_len+1];
+  Trial trials[max_num_trials];
+
+  int dis_slot_prices[max_dis_states][2*max_dictionary_bits];
+  int dis_prices[max_dis_states][modeled_distances];
+  int align_prices[dis_align_size];
+  int align_price_count;
+  int fill_counter;
+  State state;
+  uint8_t prev_byte;
+  bool member_finished_;
+
+  void fill_align_prices() throw();
+  void fill_distance_prices() throw();
+
+  uint32_t crc() const throw() { return crc_ ^ 0xFFFFFFFF; }
+
+  void mtf_reps( const int dis, int reps[num_rep_distances] ) throw()
+    {
+    if( dis >= num_rep_distances )
+      {
+      for( int i = num_rep_distances - 1; i > 0; --i ) reps[i] = reps[i-1];
+      reps[0] = dis - num_rep_distances;
+      }
+    else if( dis > 0 )
+      {
+      const int distance = reps[dis];
+      for( int i = dis; i > 0; --i ) reps[i] = reps[i-1];
+      reps[0] = distance;
+      }
+    }
+
+  int price_rep_len1( const State & state, const int pos_state ) const throw()
+    {
+    return price0( bm_rep0[state()] ) + price0( bm_len[state()][pos_state] );
+    }
+
+  int price_rep( const int rep, const int len, const State & state,
+                 const int pos_state ) const throw()
+    {
+    int price = rep_match_len_encoder.price( len, pos_state );
+    if( rep == 0 )
+      {
+      price += price0( bm_rep0[state()] );
+      price += price1( bm_len[state()][pos_state] );
+      }
+    else
+      {
+      price += price1( bm_rep0[state()] );
+      if( rep == 1 )
+        price += price0( bm_rep1[state()] );
+      else
+        {
+        price += price1( bm_rep1[state()] );
+        price += price_bit( bm_rep2[state()], rep - 2 );
+        }
+      }
+    return price;
+    }
+
+  int price_pair( const int dis, const int len, const int pos_state ) const throw()
+    {
+    if( len <= min_match_len && dis >= modeled_distances )
+      return infinite_price;
+    int price = len_encoder.price( len, pos_state );
+    const int dis_state = get_dis_state( len );
+    if( dis < modeled_distances )
+      price += dis_prices[dis_state][dis];
+    else
+      price += dis_slot_prices[dis_state][dis_slots[dis]] +
+               align_prices[dis & dis_align_mask];
+    return price;
+    }
+
+  void encode_pair( const uint32_t dis, const int len, const int pos_state ) throw()
+    {
+    len_encoder.encode( range_encoder, len, pos_state );
+    const int dis_slot = dis_slots[dis];
+    range_encoder.encode_tree( bm_dis_slot[get_dis_state(len)], dis_slot, dis_slot_bits );
+
+    if( dis_slot >= start_dis_model )
+      {
+      const int direct_bits = ( dis_slot >> 1 ) - 1;
+      const uint32_t base = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
+      const uint32_t direct_dis = dis - base;
+
+      if( dis_slot < end_dis_model )
+        range_encoder.encode_tree_reversed( bm_dis + base - dis_slot,
+                                            direct_dis, direct_bits );
+      else
+        {
+        range_encoder.encode( direct_dis >> dis_align_bits, direct_bits - dis_align_bits );
+        range_encoder.encode_tree_reversed( bm_align, direct_dis, dis_align_bits );
+        if( --align_price_count <= 0 ) fill_align_prices();
+        }
+      }
+    }
+
+  int read_match_distances() throw()
+    {
+    int len = matchfinder.longest_match_len( match_distances );
+    if( len == matchfinder.match_len_limit() )
+      len += matchfinder.true_match_len( len, match_distances[len] + 1, max_match_len - len );
+    return len;
+    }
+
+  bool move_pos( int n, bool skip = false ) throw()
+    {
+    while( --n >= 0 )
+      {
+      if( skip ) skip = false;
+      else matchfinder.longest_match_len();
+      if( !matchfinder.move_pos() ) return false;
+      }
+    return true;
+    }
+
+  void backward( int cur )
+    {
+    int & dis = trials[cur].dis;
+    while( cur > 0 )
+      {
+      const int prev_index = trials[cur].prev_index;
+      Trial & prev_trial = trials[prev_index];
+      std::swap( dis, prev_trial.dis );
+      prev_trial.price = cur - prev_index;		// len
+      cur = prev_index;
+      }
+    }
+
+  int best_pair_sequence( const int reps[num_rep_distances],
+                          const State & state );
+
+  void flush( const State & state );
+
+public:
+  LZ_encoder( Matchfinder & mf, const File_header & header,
+              const long long member_size );
+
+  bool encode_member();
+  void finish_member()
+    { if( !member_finished_ ) { flush( state ); member_finished_ = true; } }
+  bool member_finished() const throw()
+    { return member_finished_ && !range_encoder.used_bytes(); }
+  int read_data( uint8_t * const buffer, const int size ) throw()
+    { return range_encoder.read_data( buffer, size ); }
+
+  long long member_position() const throw()
+    { return range_encoder.member_position(); }
+  };