Merging upstream version 1.4~rc2.

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

1 files changed, 30 insertions, 593 deletions

diff --git a/decoder.c b/decoder.c
index d3ea0d6..1f4cbf1 100644
--- a/decoder.c
+++ b/decoder.c
@@ -1,5 +1,5 @@
 /*  Lzlib - A compression library for lzip files
-    Copyright (C) 2009, 2010, 2011, 2012 Antonio Diaz Diaz.
+    Copyright (C) 2009, 2010, 2011, 2012, 2013 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
@@ -25,593 +25,23 @@
     Public License.
 */
 
-struct Circular_buffer
-  {
-  uint8_t * buffer;
-  int buffer_size;		/* capacity == buffer_size - 1 */
-  int get;			/* buffer is empty when get == put */
-  int put;
-  };
-
-static inline void Cb_reset( struct Circular_buffer * const cb )
-  { cb->get = 0; cb->put = 0; }
-
-static inline bool Cb_init( struct Circular_buffer * const cb,
-                            const int buf_size )
-  {
-  cb->buffer = (uint8_t *)malloc( buf_size + 1 );
-  cb->buffer_size = buf_size + 1;
-  cb->get = 0;
-  cb->put = 0;
-  return ( cb->buffer != 0 );
-  }
-
-static inline void Cb_free( struct Circular_buffer * const cb )
-  { free( cb->buffer ); cb->buffer = 0; }
-
-static inline int Cb_used_bytes( const struct Circular_buffer * const cb )
-    { return ( (cb->get <= cb->put) ? 0 : cb->buffer_size ) + cb->put - cb->get; }
-
-static inline int Cb_free_bytes( const struct Circular_buffer * const cb )
-    { return ( (cb->get <= cb->put) ? cb->buffer_size : 0 ) - cb->put + cb->get - 1; }
-
-static inline uint8_t Cb_get_byte( struct Circular_buffer * const cb )
-    {
-    const uint8_t b = cb->buffer[cb->get];
-    if( ++cb->get >= cb->buffer_size ) cb->get = 0;
-    return b;
-    }
-
-static inline void Cb_put_byte( struct Circular_buffer * const cb,
-                                const uint8_t b )
-    {
-    cb->buffer[cb->put] = b;
-    if( ++cb->put >= cb->buffer_size ) cb->put = 0;
-    }
-
-
-/* Copies up to 'out_size' bytes to 'out_buffer' and updates 'get'.
-   Returns the number of bytes copied.
-*/
-static int Cb_read_data( struct Circular_buffer * const cb,
-                         uint8_t * const out_buffer, const int out_size )
-  {
-  if( out_size < 0 ) return 0;
-  int size = 0;
-  if( cb->get > cb->put )
-    {
-    size = min( cb->buffer_size - cb->get, out_size );
-    if( size > 0 )
-      {
-      memcpy( out_buffer, cb->buffer + cb->get, size );
-      cb->get += size;
-      if( cb->get >= cb->buffer_size ) cb->get = 0;
-      }
-    }
-  if( cb->get < cb->put )
-    {
-    const int size2 = min( cb->put - cb->get, out_size - size );
-    if( size2 > 0 )
-      {
-      memcpy( out_buffer + size, cb->buffer + cb->get, size2 );
-      cb->get += size2;
-      size += size2;
-      }
-    }
-  return size;
-  }
-
-
-/* Copies up to 'in_size' bytes from 'in_buffer' and updates 'put'.
-   Returns the number of bytes copied.
-*/
-static int Cb_write_data( struct Circular_buffer * const cb,
-                          const uint8_t * const in_buffer, const int in_size )
-  {
-  if( in_size < 0 ) return 0;
-  int size = 0;
-  if( cb->put >= cb->get )
-    {
-    size = min( cb->buffer_size - cb->put - (cb->get == 0), in_size );
-    if( size > 0 )
-      {
-      memcpy( cb->buffer + cb->put, in_buffer, size );
-      cb->put += size;
-      if( cb->put >= cb->buffer_size ) cb->put = 0;
-      }
-    }
-  if( cb->put < cb->get )
-    {
-    const int size2 = min( cb->get - cb->put - 1, in_size - size );
-    if( size2 > 0 )
-      {
-      memcpy( cb->buffer + cb->put, in_buffer + size, size2 );
-      cb->put += size2;
-      size += size2;
-      }
-    }
-  return size;
-  }
-
-
-enum { rd_min_available_bytes = 8 };
-
-struct Range_decoder
-  {
-  struct Circular_buffer cb;
-  long long member_position;
-  uint32_t code;
-  uint32_t range;
-  bool reload_pending;
-  bool at_stream_end;
-  };
-
-static inline bool Rd_init( struct Range_decoder * const rdec )
-  {
-  if( !Cb_init( &rdec->cb, 65536 + rd_min_available_bytes ) ) return false;
-  rdec->member_position = 0;
-  rdec->code = 0;
-  rdec->range = 0xFFFFFFFFU;
-  rdec->reload_pending = false;
-  rdec->at_stream_end = false;
-  return true;
-  }
-
-static inline void Rd_free( struct Range_decoder * const rdec )
-  { Cb_free( &rdec->cb ); }
-
-static inline int Rd_available_bytes( const struct Range_decoder * const rdec )
-  { return Cb_used_bytes( &rdec->cb ); }
-
-static inline void Rd_finish( struct Range_decoder * const rdec )
-  { rdec->at_stream_end = true; }
-
-static inline bool Rd_finished( const struct Range_decoder * const rdec )
-  { return rdec->at_stream_end && !Cb_used_bytes( &rdec->cb ); }
-
-static inline int Rd_free_bytes( const struct Range_decoder * const rdec )
-  { if( rdec->at_stream_end ) return 0; return Cb_free_bytes( &rdec->cb ); }
-
-static inline void Rd_purge( struct Range_decoder * const rdec )
-  { rdec->at_stream_end = true; Cb_reset( &rdec->cb ); }
-
-static inline void Rd_reset( struct Range_decoder * const rdec )
-  { rdec->at_stream_end = false; Cb_reset( &rdec->cb ); }
-
-
-/* Seeks a member header and updates 'get'.
-   Returns true if it finds a valid header.
-*/
-static bool Rd_find_header( struct Range_decoder * const rdec )
-  {
-  while( rdec->cb.get != rdec->cb.put )
-    {
-    if( rdec->cb.buffer[rdec->cb.get] == magic_string[0] )
-      {
-      int g = rdec->cb.get;
-      int i;
-      File_header header;
-      for( i = 0; i < Fh_size; ++i )
-        {
-        if( g == rdec->cb.put ) return false;	/* not enough data */
-        header[i] = rdec->cb.buffer[g];
-        if( ++g >= rdec->cb.buffer_size ) g = 0;
-        }
-      if( Fh_verify( header ) ) return true;
-      }
-    if( ++rdec->cb.get >= rdec->cb.buffer_size ) rdec->cb.get = 0;
-    }
-  return false;
-  }
-
-
-/* Returns true, fills 'header', and updates 'get' if 'get' points to a
-   valid header.
-   Else returns false and leaves 'get' unmodified.
-*/
-static bool Rd_read_header( struct Range_decoder * const rdec,
-                            File_header header )
-  {
-  int g = rdec->cb.get;
-  int i;
-  for( i = 0; i < Fh_size; ++i )
-    {
-    if( g == rdec->cb.put ) return false;	/* not enough data */
-    header[i] = rdec->cb.buffer[g];
-    if( ++g >= rdec->cb.buffer_size ) g = 0;
-    }
-  if( Fh_verify( header ) )
-    {
-    rdec->cb.get = g;
-    rdec->member_position = Fh_size;
-    rdec->reload_pending = true;
-    return true;
-    }
-  return false;
-  }
-
-
-static inline int Rd_write_data( struct Range_decoder * const rdec,
-                                 const uint8_t * const inbuf, const int size )
-  {
-  if( rdec->at_stream_end || size <= 0 ) return 0;
-  return Cb_write_data( &rdec->cb, inbuf, size );
-  }
-
-static inline uint8_t Rd_get_byte( struct Range_decoder * const rdec )
-  {
-  ++rdec->member_position;
-  return Cb_get_byte( &rdec->cb );
-  }
-
-
-static bool Rd_try_reload( struct Range_decoder * const rdec, const bool force )
-  {
-  if( force ) rdec->reload_pending = true;
-  if( rdec->reload_pending && Rd_available_bytes( rdec ) >= 5 )
-    {
-    int i;
-    rdec->reload_pending = false;
-    rdec->code = 0;
-    rdec->range = 0xFFFFFFFFU;
-    for( i = 0; i < 5; ++i )
-      rdec->code = (rdec->code << 8) | Rd_get_byte( rdec );
-    }
-  return !rdec->reload_pending;
-  }
-
-
-static inline int Rd_decode( struct Range_decoder * const rdec,
-                             const int num_bits )
-  {
-  int symbol = 0;
-  int i;
-  for( i = num_bits; i > 0; --i )
-    {
-    symbol <<= 1;
-    if( rdec->range <= 0x00FFFFFFU )
-      {
-      rdec->range <<= 7;
-      rdec->code = (rdec->code << 8) | Rd_get_byte( rdec );
-      if( rdec->code >= rdec->range )
-        { rdec->code -= rdec->range; symbol |= 1; }
-      }
-    else
-      {
-      rdec->range >>= 1;
-      if( rdec->code >= rdec->range )
-        { rdec->code -= rdec->range; symbol |= 1; }
-      }
-    }
-  return symbol;
-  }
-
-
-static inline void Rd_normalize( struct Range_decoder * const rdec )
-  {
-  if( rdec->range <= 0x00FFFFFFU )
-    {
-    rdec->range <<= 8;
-    rdec->code = (rdec->code << 8) | Rd_get_byte( rdec );
-    }
-  }
-
-
-static inline int Rd_decode_bit( struct Range_decoder * const rdec,
-                                 Bit_model * const probability )
-  {
-  uint32_t bound;
-  Rd_normalize( rdec );
-  bound = ( rdec->range >> bit_model_total_bits ) * *probability;
-  if( rdec->code < bound )
-    {
-    rdec->range = bound;
-    *probability += (bit_model_total - *probability) >> bit_model_move_bits;
-    return 0;
-    }
-  else
-    {
-    rdec->range -= bound;
-    rdec->code -= bound;
-    *probability -= *probability >> bit_model_move_bits;
-    return 1;
-    }
-  }
-
-
-static inline int Rd_decode_tree( struct Range_decoder * const rdec,
-                                  Bit_model bm[], const int num_bits )
-  {
-  int model = 1;
-  int i;
-  for( i = num_bits; i > 0; --i )
-    model = ( model << 1 ) | Rd_decode_bit( rdec, &bm[model] );
-  return model - (1 << num_bits);
-  }
-
-
-static inline int Rd_decode_matched( struct Range_decoder * const rdec,
-                                     Bit_model bm[], const int match_byte )
-  {
-  Bit_model * const bm1 = bm + 0x100;
-  int symbol = 1;
-  int i;
-  for( i = 7; i >= 0; --i )
-    {
-    const int match_bit = ( match_byte >> i ) & 1;
-    const int bit = Rd_decode_bit( rdec, &bm1[(match_bit<<8)+symbol] );
-    symbol = ( symbol << 1 ) | bit;
-    if( match_bit != bit )
-      {
-      while( --i >= 0 )
-        symbol = ( symbol << 1 ) | Rd_decode_bit( rdec, &bm[symbol] );
-      break;
-      }
-    }
-  return symbol & 0xFF;
-  }
-
-
-static inline int Rd_decode_tree_reversed( struct Range_decoder * const rdec,
-                                           Bit_model bm[], const int num_bits )
-  {
-  int model = 1;
-  int symbol = 0;
-  int i;
-  for( i = 0; i < num_bits; ++i )
-    {
-    const int bit = Rd_decode_bit( rdec, &bm[model] );
-    model <<= 1;
-    if( bit ) { model |= 1; symbol |= (1 << i); }
-    }
-  return symbol;
-  }
-
-
-static inline bool Rd_enough_available_bytes( const struct Range_decoder * const rdec )
-  {
-  return ( Cb_used_bytes( &rdec->cb ) >= rd_min_available_bytes ||
-           ( rdec->at_stream_end && Cb_used_bytes( &rdec->cb ) > 0 ) );
-  }
-
-
-static inline int Rd_read_data( struct Range_decoder * const rdec,
-                                uint8_t * const outbuf, const int size )
-  {
-  const int sz = Cb_read_data( &rdec->cb, outbuf, size );
-  if( sz > 0 ) rdec->member_position += sz;
-  return sz;
-  }
-
-
-struct Len_decoder
-  {
-  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];
-  };
-
-static inline void Led_init( struct Len_decoder * const len_decoder )
-  {
-  int i, j;
-  Bm_init( &len_decoder->choice1 );
-  Bm_init( &len_decoder->choice2 );
-  for( i = 0; i < pos_states; ++i )
-    for( j = 0; j < len_low_symbols; ++j )
-      Bm_init( &len_decoder->bm_low[i][j] );
-  for( i = 0; i < pos_states; ++i )
-    for( j = 0; j < len_mid_symbols; ++j )
-      Bm_init( &len_decoder->bm_mid[i][j] );
-  for( i = 0; i < len_high_symbols; ++i )
-    Bm_init( &len_decoder->bm_high[i] );
-  }
-
-static inline int Led_decode( struct Len_decoder * const len_decoder,
-                              struct Range_decoder * const rdec,
-                              const int pos_state )
-  {
-  if( Rd_decode_bit( rdec, &len_decoder->choice1 ) == 0 )
-    return Rd_decode_tree( rdec, len_decoder->bm_low[pos_state], len_low_bits );
-  if( Rd_decode_bit( rdec, &len_decoder->choice2 ) == 0 )
-    return len_low_symbols +
-           Rd_decode_tree( rdec, len_decoder->bm_mid[pos_state], len_mid_bits );
-  return len_low_symbols + len_mid_symbols +
-         Rd_decode_tree( rdec, len_decoder->bm_high, len_high_bits );
-  }
-
-
-struct Literal_decoder
-  {
-  Bit_model bm_literal[1<<literal_context_bits][0x300];
-  };
-
-static inline void Lid_init( struct Literal_decoder * const lidec )
-  {
-  int i, j;
-  for( i = 0; i < 1<<literal_context_bits; ++i )
-    for( j = 0; j < 0x300; ++j )
-      Bm_init( &lidec->bm_literal[i][j] );
-  }
-
-static inline int Lid_state( const uint8_t prev_byte )
-  { return ( prev_byte >> ( 8 - literal_context_bits ) ); }
-
-static inline uint8_t Lid_decode( struct Literal_decoder * const lidec,
-                                  struct Range_decoder * const rdec,
-                                  const uint8_t prev_byte )
-  { return Rd_decode_tree( rdec, lidec->bm_literal[Lid_state(prev_byte)], 8 ); }
-
-static inline uint8_t Lid_decode_matched( struct Literal_decoder * const lidec,
-                                          struct Range_decoder * const rdec,
-                                          const uint8_t prev_byte,
-                                          const uint8_t match_byte )
-  { return Rd_decode_matched( rdec, lidec->bm_literal[Lid_state(prev_byte)], match_byte ); }
-
-
-enum { lzd_min_free_bytes = max_match_len };
-
-struct LZ_decoder
-  {
-  struct Circular_buffer cb;
-  long long partial_data_pos;
-  int dictionary_size;
-  uint32_t crc;
-  int member_version;
-  bool member_finished;
-  bool verify_trailer_pending;
-  unsigned int rep0;		/* rep[0-3] latest four distances */
-  unsigned int rep1;		/* used for efficient coding of */
-  unsigned int rep2;		/* repeated distances */
-  unsigned int rep3;
-  State state;
-
-  Bit_model bm_match[states][pos_states];
-  Bit_model bm_rep[states];
-  Bit_model bm_rep0[states];
-  Bit_model bm_rep1[states];
-  Bit_model bm_rep2[states];
-  Bit_model bm_len[states][pos_states];
-  Bit_model bm_dis_slot[max_dis_states][1<<dis_slot_bits];
-  Bit_model bm_dis[modeled_distances-end_dis_model+1];
-  Bit_model bm_align[dis_align_size];
-
-  struct Range_decoder * range_decoder;
-  struct Len_decoder len_decoder;
-  struct Len_decoder rep_match_len_decoder;
-  struct Literal_decoder literal_decoder;
-  };
-
-static inline bool LZd_init( struct LZ_decoder * const decoder,
-                             const File_header header,
-                             struct Range_decoder * const rdec )
-  {
-  int i, j;
-  if( !Cb_init( &decoder->cb, max( 65536, Fh_get_dictionary_size( header ) ) + lzd_min_free_bytes ) )
-    return false;
-  decoder->partial_data_pos = 0;
-  decoder->dictionary_size = Fh_get_dictionary_size( header );
-  decoder->crc = 0xFFFFFFFFU;
-  decoder->member_version = Fh_version( header );
-  decoder->member_finished = false;
-  decoder->verify_trailer_pending = false;
-  decoder->rep0 = 0;
-  decoder->rep1 = 0;
-  decoder->rep2 = 0;
-  decoder->rep3 = 0;
-  decoder->state = 0;
-
-  for( i = 0; i < states; ++i )
-    {
-    for( j = 0; j < pos_states; ++j )
-      {
-      Bm_init( &decoder->bm_match[i][j] );
-      Bm_init( &decoder->bm_len[i][j] );
-      }
-    Bm_init( &decoder->bm_rep[i] );
-    Bm_init( &decoder->bm_rep0[i] );
-    Bm_init( &decoder->bm_rep1[i] );
-    Bm_init( &decoder->bm_rep2[i] );
-    }
-  for( i = 0; i < max_dis_states; ++i )
-    for( j = 0; j < 1<<dis_slot_bits; ++j )
-      Bm_init( &decoder->bm_dis_slot[i][j] );
-  for( i = 0; i < modeled_distances-end_dis_model+1; ++i )
-    Bm_init( &decoder->bm_dis[i] );
-  for( i = 0; i < dis_align_size; ++i )
-    Bm_init( &decoder->bm_align[i] );
-
-  decoder->range_decoder = rdec;
-  Led_init( &decoder->len_decoder );
-  Led_init( &decoder->rep_match_len_decoder );
-  Lid_init( &decoder->literal_decoder );
-  decoder->cb.buffer[decoder->cb.buffer_size-1] = 0; /* prev_byte of first_byte */
-  return true;
-  }
-
-static inline void LZd_free( struct LZ_decoder * const decoder )
-  { Cb_free( &decoder->cb ); }
-
-static inline bool LZd_member_finished( const struct LZ_decoder * const decoder )
-  { return ( decoder->member_finished && !Cb_used_bytes( &decoder->cb ) ); }
-
-static inline uint32_t LZd_crc( const struct LZ_decoder * const decoder )
-  { return decoder->crc ^ 0xFFFFFFFFU; }
-
-static inline long long LZd_data_position( const struct LZ_decoder * const decoder )
-  { return decoder->partial_data_pos + decoder->cb.put; }
-
-
 static bool LZd_verify_trailer( struct LZ_decoder * const decoder )
   {
   File_trailer trailer;
   const int trailer_size = Ft_versioned_size( decoder->member_version );
-  const long long member_size =
+  const unsigned long long member_size =
     decoder->range_decoder->member_position + trailer_size;
 
   int size = Rd_read_data( decoder->range_decoder, trailer, trailer_size );
-  if( size < trailer_size ) return false;
+  if( size < trailer_size )
+    return false;
 
   if( decoder->member_version == 0 ) Ft_set_member_size( trailer, member_size );
 
-  if( decoder->range_decoder->code != 0 ||
-      Ft_get_data_crc( trailer ) != LZd_crc( decoder ) ||
-      Ft_get_data_size( trailer ) != LZd_data_position( decoder ) ||
-      Ft_get_member_size( trailer ) != member_size ) return false;
-  return true;
-  }
-
-
-static inline void LZd_copy_block( struct LZ_decoder * const decoder,
-                                   const int distance, int len )
-  {
-  int i = decoder->cb.put - distance - 1;
-  if( i < 0 ) i += decoder->cb.buffer_size;
-  if( len < decoder->cb.buffer_size - max( decoder->cb.put, i ) &&
-      len <= abs( decoder->cb.put - i ) )
-    {
-    CRC32_update_buf( &decoder->crc, decoder->cb.buffer + i, len );
-    memcpy( decoder->cb.buffer + decoder->cb.put, decoder->cb.buffer + i, len );
-    decoder->cb.put += len;
-    }
-  else for( ; len > 0; --len )
-    {
-    CRC32_update_byte( &decoder->crc, decoder->cb.buffer[i] );
-    decoder->cb.buffer[decoder->cb.put] = decoder->cb.buffer[i];
-    if( ++decoder->cb.put >= decoder->cb.buffer_size )
-      { decoder->partial_data_pos += decoder->cb.put; decoder->cb.put = 0; }
-    if( ++i >= decoder->cb.buffer_size ) i = 0;
-    }
-  }
-
-
-static inline bool LZd_enough_free_bytes( const struct LZ_decoder * const decoder )
-  { return Cb_free_bytes( &decoder->cb ) >= lzd_min_free_bytes; }
-
-
-static inline uint8_t LZd_get_byte( const struct LZ_decoder * const decoder,
-                                    const int distance )
-  {
-  int i = decoder->cb.put - distance - 1;
-  if( i < 0 ) i += decoder->cb.buffer_size;
-  return decoder->cb.buffer[i];
-  }
-
-static inline uint8_t LZd_get_prev_byte( const struct LZ_decoder * const decoder )
-  {
-  const int i =
-    ( ( decoder->cb.put > 0 ) ? decoder->cb.put : decoder->cb.buffer_size ) - 1;
-  return decoder->cb.buffer[i];
-  }
-
-static inline void LZd_put_byte( struct LZ_decoder * const decoder,
-                                 const uint8_t b )
-  {
-  CRC32_update_byte( &decoder->crc, b );
-  decoder->cb.buffer[decoder->cb.put] = b;
-  if( ++decoder->cb.put >= decoder->cb.buffer_size )
-    { decoder->partial_data_pos += decoder->cb.put; decoder->cb.put = 0; }
+  return ( decoder->range_decoder->code == 0 &&
+           Ft_get_data_crc( trailer ) == LZd_crc( decoder ) &&
+           Ft_get_data_size( trailer ) == LZd_data_position( decoder ) &&
+           Ft_get_member_size( trailer ) == member_size );
   }
 
 
@@ -642,12 +72,17 @@ static int LZd_decode_member( struct LZ_decoder * const decoder )
       {
       const uint8_t prev_byte = LZd_get_prev_byte( decoder );
       if( St_is_char( *state ) )
-        LZd_put_byte( decoder, Lid_decode( &decoder->literal_decoder,
-          decoder->range_decoder, prev_byte ) );
+        {
+        *state -= ( *state < 4 ) ? *state : 3;
+        LZd_put_byte( decoder, Rd_decode_tree( decoder->range_decoder,
+                      decoder->bm_literal[get_lit_state(prev_byte)], 8 ) );
+        }
       else
-        LZd_put_byte( decoder, Lid_decode_matched( &decoder->literal_decoder,
-          decoder->range_decoder, prev_byte, LZd_get_byte( decoder, decoder->rep0 ) ) );
-      St_set_char( state );
+        {
+        *state -= ( *state < 10 ) ? 3 : 6;
+        LZd_put_byte( decoder, Rd_decode_matched( decoder->range_decoder,
+          decoder->bm_literal[get_lit_state(prev_byte)], LZd_get_byte( decoder, decoder->rep0 ) ) );
+        }
       }
     else
       {
@@ -657,7 +92,7 @@ static int LZd_decode_member( struct LZ_decoder * const decoder )
         len = 0;
         if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_rep0[*state] ) == 1 )
           {
-          unsigned int distance;
+          unsigned distance;
           if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_rep1[*state] ) == 0 )
             distance = decoder->rep1;
           else
@@ -673,31 +108,33 @@ static int LZd_decode_member( struct LZ_decoder * const decoder )
         else
           {
           if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_len[*state][pos_state] ) == 0 )
-            { St_set_short_rep( state ); len = 1; }
+            { *state = St_set_short_rep( *state ); len = 1; }
           }
         if( len == 0 )
           {
-          St_set_rep( state );
+          *state = St_set_rep( *state );
           len = min_match_len + Led_decode( &decoder->rep_match_len_decoder, decoder->range_decoder, pos_state );
           }
         }
       else
         {
         int dis_slot;
-        const unsigned int rep0_saved = decoder->rep0;
+        const unsigned rep0_saved = decoder->rep0;
         len = min_match_len + Led_decode( &decoder->len_decoder, decoder->range_decoder, pos_state );
-        dis_slot = Rd_decode_tree( decoder->range_decoder, decoder->bm_dis_slot[get_dis_state(len)], dis_slot_bits );
+        dis_slot = Rd_decode_tree6( decoder->range_decoder, decoder->bm_dis_slot[get_dis_state(len)] );
         if( dis_slot < start_dis_model ) decoder->rep0 = dis_slot;
         else
           {
           const int direct_bits = ( dis_slot >> 1 ) - 1;
           decoder->rep0 = ( 2 | ( dis_slot & 1 ) ) << direct_bits;
           if( dis_slot < end_dis_model )
-            decoder->rep0 += Rd_decode_tree_reversed( decoder->range_decoder, decoder->bm_dis + decoder->rep0 - dis_slot, direct_bits );
+            decoder->rep0 += Rd_decode_tree_reversed( decoder->range_decoder,
+                             decoder->bm_dis + decoder->rep0 - dis_slot - 1,
+                             direct_bits );
           else
             {
             decoder->rep0 += Rd_decode( decoder->range_decoder, direct_bits - dis_align_bits ) << dis_align_bits;
-            decoder->rep0 += Rd_decode_tree_reversed( decoder->range_decoder, decoder->bm_align, dis_align_bits );
+            decoder->rep0 += Rd_decode_tree_reversed4( decoder->range_decoder, decoder->bm_align );
             if( decoder->rep0 == 0xFFFFFFFFU )		/* Marker found */
               {
               decoder->rep0 = rep0_saved;
@@ -721,9 +158,9 @@ static int LZd_decode_member( struct LZ_decoder * const decoder )
           }
         decoder->rep3 = decoder->rep2;
         decoder->rep2 = decoder->rep1; decoder->rep1 = rep0_saved;
-        St_set_match( state );
-        if( decoder->rep0 >= (unsigned int)decoder->dictionary_size ||
-            ( decoder->rep0 >= (unsigned int)decoder->cb.put &&
+        *state = St_set_match( *state );
+        if( decoder->rep0 >= (unsigned)decoder->dictionary_size ||
+            ( decoder->rep0 >= (unsigned)decoder->cb.put &&
               !decoder->partial_data_pos ) )
           return 1;
         }