Merging upstream version 1.3.

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

1 files changed, 734 insertions, 0 deletions

diff --git a/decoder.c b/decoder.c
new file mode 100644
index 0000000..d3ea0d6
--- /dev/null
+++ b/decoder.c
@@ -0,0 +1,734 @@
+/*  Lzlib - A compression library for lzip files
+    Copyright (C) 2009, 2010, 2011, 2012 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 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.
+*/
+
+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 =
+    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( 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 value: 0 = OK, 1 = decoder error, 2 = unexpected EOF,
+                 3 = trailer error, 4 = unknown marker found. */
+static int LZd_decode_member( struct LZ_decoder * const decoder )
+  {
+  State * const state = &decoder->state;
+  if( decoder->member_finished ) return 0;
+  if( !Rd_try_reload( decoder->range_decoder, false ) ) return 0;
+  if( decoder->verify_trailer_pending )
+    {
+    if( Rd_available_bytes( decoder->range_decoder ) < Ft_versioned_size( decoder->member_version ) &&
+        !decoder->range_decoder->at_stream_end )
+      return 0;
+    decoder->verify_trailer_pending = false;
+    decoder->member_finished = true;
+    if( LZd_verify_trailer( decoder ) ) return 0; else return 3;
+    }
+
+  while( !Rd_finished( decoder->range_decoder ) )
+    {
+    const int pos_state = LZd_data_position( decoder ) & pos_state_mask;
+    if( !Rd_enough_available_bytes( decoder->range_decoder ) ||
+        !LZd_enough_free_bytes( decoder ) )
+      return 0;
+    if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_match[*state][pos_state] ) == 0 )
+      {
+      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 ) );
+      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 );
+      }
+    else
+      {
+      int len;
+      if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_rep[*state] ) == 1 )
+        {
+        len = 0;
+        if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_rep0[*state] ) == 1 )
+          {
+          unsigned int distance;
+          if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_rep1[*state] ) == 0 )
+            distance = decoder->rep1;
+          else
+            {
+            if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_rep2[*state] ) == 0 )
+              distance = decoder->rep2;
+            else { distance = decoder->rep3; decoder->rep3 = decoder->rep2; }
+            decoder->rep2 = decoder->rep1;
+            }
+          decoder->rep1 = decoder->rep0;
+          decoder->rep0 = distance;
+          }
+        else
+          {
+          if( Rd_decode_bit( decoder->range_decoder, &decoder->bm_len[*state][pos_state] ) == 0 )
+            { St_set_short_rep( state ); len = 1; }
+          }
+        if( len == 0 )
+          {
+          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;
+        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 );
+        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 );
+          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 );
+            if( decoder->rep0 == 0xFFFFFFFFU )		/* Marker found */
+              {
+              decoder->rep0 = rep0_saved;
+              Rd_normalize( decoder->range_decoder );
+              if( len == min_match_len )	/* End Of Stream marker */
+                {
+                if( Rd_available_bytes( decoder->range_decoder ) < Ft_versioned_size( decoder->member_version ) &&
+                    !decoder->range_decoder->at_stream_end )
+                  { decoder->verify_trailer_pending = true; return 0; }
+                decoder->member_finished = true;
+                if( LZd_verify_trailer( decoder ) ) return 0; else return 3;
+                }
+              if( len == min_match_len + 1 )	/* Sync Flush marker */
+                {
+                if( Rd_try_reload( decoder->range_decoder, true ) ) continue;
+                else return 0;
+                }
+              return 4;
+              }
+            }
+          }
+        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 &&
+              !decoder->partial_data_pos ) )
+          return 1;
+        }
+      LZd_copy_block( decoder, decoder->rep0, len );
+      }
+    }
+  return 2;
+  }