Merging upstream version 1.7~pre1.

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

1 files changed, 203 insertions, 0 deletions

diff --git a/fast_encoder.c b/fast_encoder.c
new file mode 100644
index 0000000..6172b1a
--- /dev/null
+++ b/fast_encoder.c
@@ -0,0 +1,203 @@
+/*  Lzlib - Compression library for the lzip format
+    Copyright (C) 2009-2015 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 2 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 library.  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.
+*/
+
+int FLZe_longest_match_len( struct FLZ_encoder * const fe, int * const distance )
+  {
+  enum { len_limit = 16 };
+  const uint8_t * const data = Mb_ptr_to_current_pos( &fe->eb.mb );
+  int32_t * ptr0 = fe->eb.mb.pos_array + fe->eb.mb.cyclic_pos;
+  int32_t * newptr;
+  const int pos1 = fe->eb.mb.pos + 1;
+  int maxlen = 0;
+  int count, delta, newpos;
+  if( len_limit > Mb_available_bytes( &fe->eb.mb ) ) { *ptr0 = 0; return 0; }
+
+  fe->key4 = ( ( fe->key4 << 4 ) ^ data[3] ) & fe->eb.mb.key4_mask;
+  newpos = fe->eb.mb.prev_positions[fe->key4];
+  fe->eb.mb.prev_positions[fe->key4] = pos1;
+
+
+  for( count = 4; ; )
+    {
+    if( --count < 0 || newpos <= 0 ) { *ptr0 = 0; break; }
+    delta = pos1 - newpos;
+    if( delta > fe->eb.mb.dictionary_size ) { *ptr0 = 0; break; }
+    newptr = fe->eb.mb.pos_array +
+      ( fe->eb.mb.cyclic_pos - delta +
+        ( ( fe->eb.mb.cyclic_pos >= delta ) ? 0 : fe->eb.mb.dictionary_size + 1 ) );
+
+    if( data[maxlen-delta] == data[maxlen] )
+      {
+      int len = 0;
+      while( len < len_limit && data[len-delta] == data[len] ) ++len;
+      if( maxlen < len ) { maxlen = len; *distance = delta - 1; }
+      }
+
+    if( maxlen < len_limit )
+      {
+      *ptr0 = newpos;
+      ptr0 = newptr;
+      newpos = *ptr0;
+      }
+    else
+      {
+      *ptr0 = *newptr;
+      maxlen += Mb_true_match_len( &fe->eb.mb, maxlen, *distance + 1,
+                                   max_match_len - maxlen );
+      break;
+      }
+    }
+  return maxlen;
+  }
+
+
+bool FLZe_encode_member( struct FLZ_encoder * const fe )
+  {
+  int rep = 0, i;
+  State * const state = &fe->eb.state;
+
+  if( fe->eb.member_finished ) return true;
+  if( Re_member_position( &fe->eb.renc ) >= fe->eb.member_size_limit )
+    {
+    if( LZeb_full_flush( &fe->eb ) ) fe->eb.member_finished = true;
+    return true;
+    }
+
+  if( Mb_data_position( &fe->eb.mb ) == 0 &&
+      !Mb_data_finished( &fe->eb.mb ) )		/* encode first byte */
+    {
+    const uint8_t prev_byte = 0;
+    uint8_t cur_byte;
+    if( !Mb_enough_available_bytes( &fe->eb.mb ) ||
+        !Re_enough_free_bytes( &fe->eb.renc ) ) return true;
+    cur_byte = Mb_peek( &fe->eb.mb, 0 );
+    Re_encode_bit( &fe->eb.renc, &fe->eb.bm_match[*state][0], 0 );
+    LZeb_encode_literal( &fe->eb, prev_byte, cur_byte );
+    CRC32_update_byte( &fe->eb.crc, cur_byte );
+    FLZe_reset_key4( fe );
+    if( !FLZe_update_and_move( fe, 1 ) ) return false;
+    }
+
+  while( !Mb_data_finished( &fe->eb.mb ) &&
+         Re_member_position( &fe->eb.renc ) < fe->eb.member_size_limit )
+    {
+    int match_distance;
+    int main_len, pos_state, len;
+    if( !Mb_enough_available_bytes( &fe->eb.mb ) ||
+        !Re_enough_free_bytes( &fe->eb.renc ) ) return true;
+    main_len = FLZe_longest_match_len( fe, &match_distance );
+    pos_state = Mb_data_position( &fe->eb.mb ) & pos_state_mask;
+    len = 0;
+
+    for( i = 0; i < num_rep_distances; ++i )
+      {
+      const int tlen = Mb_true_match_len( &fe->eb.mb, 0,
+                                          fe->eb.reps[i] + 1, max_match_len );
+      if( tlen > len ) { len = tlen; rep = i; }
+      }
+    if( len > min_match_len && len + 3 > main_len )
+      {
+      CRC32_update_buf( &fe->eb.crc, Mb_ptr_to_current_pos( &fe->eb.mb ), len );
+      Re_encode_bit( &fe->eb.renc, &fe->eb.bm_match[*state][pos_state], 1 );
+      Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep[*state], 1 );
+      Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep0[*state], rep != 0 );
+      if( rep == 0 )
+        Re_encode_bit( &fe->eb.renc, &fe->eb.bm_len[*state][pos_state], 1 );
+      else
+        {
+        int distance;
+        Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep1[*state], rep > 1 );
+        if( rep > 1 )
+          Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep2[*state], rep > 2 );
+        distance = fe->eb.reps[rep];
+        for( i = rep; i > 0; --i ) fe->eb.reps[i] = fe->eb.reps[i-1];
+        fe->eb.reps[0] = distance;
+        }
+      *state = St_set_rep( *state );
+      Re_encode_len( &fe->eb.renc, &fe->eb.rep_len_model, len, pos_state );
+      if( !Mb_move_pos( &fe->eb.mb ) ) return false;
+      if( !FLZe_update_and_move( fe, len - 1 ) ) return false;
+      continue;
+      }
+
+    if( main_len > min_match_len )
+      {
+      CRC32_update_buf( &fe->eb.crc, Mb_ptr_to_current_pos( &fe->eb.mb ), main_len );
+      Re_encode_bit( &fe->eb.renc, &fe->eb.bm_match[*state][pos_state], 1 );
+      Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep[*state], 0 );
+      *state = St_set_match( *state );
+      for( i = num_rep_distances - 1; i > 0; --i ) fe->eb.reps[i] = fe->eb.reps[i-1];
+      fe->eb.reps[0] = match_distance;
+      LZeb_encode_pair( &fe->eb, match_distance, main_len, pos_state );
+      if( !Mb_move_pos( &fe->eb.mb ) ) return false;
+      if( !FLZe_update_and_move( fe, main_len - 1 ) ) return false;
+      continue;
+      }
+
+    {
+    const uint8_t prev_byte = Mb_peek( &fe->eb.mb, 1 );
+    const uint8_t cur_byte = Mb_peek( &fe->eb.mb, 0 );
+    const uint8_t match_byte = Mb_peek( &fe->eb.mb, fe->eb.reps[0] + 1 );
+    if( !Mb_move_pos( &fe->eb.mb ) ) return false;
+    CRC32_update_byte( &fe->eb.crc, cur_byte );
+
+    if( match_byte == cur_byte )
+      {
+      int price = price0( fe->eb.bm_match[*state][pos_state] );
+      int short_rep_price;
+      if( St_is_char( *state ) )
+        price += LZeb_price_literal( &fe->eb, prev_byte, cur_byte );
+      else
+        price += LZeb_price_matched( &fe->eb, prev_byte, cur_byte, match_byte );
+      short_rep_price = price1( fe->eb.bm_match[*state][pos_state] ) +
+                        price1( fe->eb.bm_rep[*state] ) +
+                        price0( fe->eb.bm_rep0[*state] ) +
+                        price0( fe->eb.bm_len[*state][pos_state] );
+      if( short_rep_price < price )
+        {
+        Re_encode_bit( &fe->eb.renc, &fe->eb.bm_match[*state][pos_state], 1 );
+        Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep[*state], 1 );
+        Re_encode_bit( &fe->eb.renc, &fe->eb.bm_rep0[*state], 0 );
+        Re_encode_bit( &fe->eb.renc, &fe->eb.bm_len[*state][pos_state], 0 );
+        *state = St_set_short_rep( *state );
+        continue;
+        }
+      }
+
+    /* literal byte */
+    Re_encode_bit( &fe->eb.renc, &fe->eb.bm_match[*state][pos_state], 0 );
+    if( St_is_char( *state ) )
+      LZeb_encode_literal( &fe->eb, prev_byte, cur_byte );
+    else
+      LZeb_encode_matched( &fe->eb, prev_byte, cur_byte, match_byte );
+    *state = St_set_char( *state );
+    }
+    }
+
+  if( LZeb_full_flush( &fe->eb ) ) fe->eb.member_finished = true;
+  return true;
+  }