Merging upstream version 1.10.

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

1 files changed, 40 insertions, 58 deletions

diff --git a/decoder.h b/decoder.h
index 212c62f..36090c5 100644
--- a/decoder.h
+++ b/decoder.h
@@ -15,74 +15,57 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-class Input_buffer
+class Range_decoder
   {
-  enum { buffer_size = 65536 };
-  uint8_t * const buffer;
+  enum { buffer_size = 16384 };
+  long long partial_member_pos;
+  uint8_t * const buffer;	// input buffer
   int pos;
   int stream_pos;		// when reached, a new block must be read
-  const int ides_;		// input file descriptor
+  uint32_t code;
+  uint32_t range;
+  const int infd_;		// input file descriptor
   bool at_stream_end;
 
   bool read_block();
 
 public:
-  Input_buffer( const int ides )
+  Range_decoder( const int infd )
     :
+    partial_member_pos( 0 ),
     buffer( new uint8_t[buffer_size] ),
     pos( 0 ),
     stream_pos( 0 ),
-    ides_( ides ),
+    code( 0 ),
+    range( 0xFFFFFFFFU ),
+    infd_( infd ),
     at_stream_end( false ) {}
 
-  ~Input_buffer() { delete[] buffer; }
+  ~Range_decoder() { delete[] buffer; }
 
+  bool code_is_zero() const throw() { return ( code == 0 ); }
   bool finished() const throw() { return at_stream_end && pos >= stream_pos; }
+  long long member_position() const throw()
+    { return partial_member_pos + pos; }
+  void reset_member_position() throw()
+    { partial_member_pos = -pos; }
 
   uint8_t get_byte()
     {
     if( pos >= stream_pos && !read_block() ) return 0;
     return buffer[pos++];
     }
-  };
-
-
-class Range_decoder
-  {
-  mutable long long member_pos;
-  uint32_t code;
-  uint32_t range;
-  Input_buffer & ibuf;
-
-public:
-  Range_decoder( const int header_size, Input_buffer & buf )
-    :
-    member_pos( header_size ),
-    code( 0 ),
-    range( 0xFFFFFFFF ),
-    ibuf( buf )
-    { for( int i = 0; i < 5; ++i ) code = (code << 8) | get_byte(); }
-
-  bool code_is_zero() const throw() { return ( code == 0 ); }
-  bool finished() const throw() { return ibuf.finished(); }
-  long long member_position() const throw() { return member_pos; }
-
-  uint8_t get_byte() const
-    {
-    ++member_pos;
-    return ibuf.get_byte();
-    }
 
-  void reload() throw()
+  void load() throw()
     {
     code = 0;
-    range = 0xFFFFFFFF;
+    range = 0xFFFFFFFFU;
     for( int i = 0; i < 5; ++i ) code = (code << 8) | get_byte();
     }
 
   void normalize()
     {
-    if( range <= 0x00FFFFFF )
+    if( range <= 0x00FFFFFFU )
       { range <<= 8; code = (code << 8) | get_byte(); }
     }
 
@@ -92,7 +75,7 @@ public:
     for( int i = num_bits; i > 0; --i )
       {
       symbol <<= 1;
-      if( range <= 0x00FFFFFF )
+      if( range <= 0x00FFFFFFU )
         {
         range <<= 7; code = (code << 8) | get_byte();
         if( code >= range ) { code -= range; symbol |= 1; }
@@ -148,16 +131,16 @@ public:
 
   int decode_matched( Bit_model bm[], const int match_byte )
     {
-    Bit_model *bm1 = bm + 0x100;
+    Bit_model * const bm1 = bm + 0x100;
     int symbol = 1;
-    for( int i = 1; i <= 8; ++i )
+    for( int i = 7; i >= 0; --i )
       {
-      const int match_bit = ( match_byte << i ) & 0x100;
-      const int bit = decode_bit( bm1[match_bit+symbol] );
+      const int match_bit = ( match_byte >> i ) & 1;
+      const int bit = decode_bit( bm1[(match_bit<<8)+symbol] );
       symbol = ( symbol << 1 ) | bit;
-      if( ( match_bit && !bit ) || ( !match_bit && bit ) )
+      if( match_bit != bit )
         {
-        while( ++i <= 8 )
+        while( --i >= 0 )
           symbol = ( symbol << 1 ) | decode_bit( bm[symbol] );
         break;
         }
@@ -193,30 +176,30 @@ class Literal_decoder
   {
   Bit_model bm_literal[1<<literal_context_bits][0x300];
 
-  int state( const int prev_byte ) const throw()
+  int lstate( const int prev_byte ) const throw()
     { return ( prev_byte >> ( 8 - literal_context_bits ) ); }
 
 public:
   uint8_t decode( Range_decoder & range_decoder, const uint8_t prev_byte )
-    { return range_decoder.decode_tree( bm_literal[state(prev_byte)], 8 ); }
+    { return range_decoder.decode_tree( bm_literal[lstate(prev_byte)], 8 ); }
 
   uint8_t decode_matched( Range_decoder & range_decoder,
                           const uint8_t prev_byte, const uint8_t match_byte )
-    { return range_decoder.decode_matched( bm_literal[state(prev_byte)], match_byte ); }
+    { return range_decoder.decode_matched( bm_literal[lstate(prev_byte)], match_byte ); }
   };
 
 
 class LZ_decoder
   {
   long long partial_data_pos;
-  const int format_version;
+  const int member_version;
   const int dictionary_size;
   const int buffer_size;
   uint8_t * const buffer;
   int pos;
   int stream_pos;		// first byte not yet written to file
   uint32_t crc_;
-  const int odes_;		// output file descriptor
+  const int outfd_;		// output file descriptor
 
   Bit_model bm_match[State::states][pos_states];
   Bit_model bm_rep[State::states];
@@ -228,7 +211,7 @@ class LZ_decoder
   Bit_model bm_dis[modeled_distances-end_dis_model];
   Bit_model bm_align[dis_align_size];
 
-  Range_decoder range_decoder;
+  Range_decoder & range_decoder;
   Len_decoder len_decoder;
   Len_decoder rep_match_len_decoder;
   Literal_decoder literal_decoder;
@@ -267,24 +250,23 @@ class LZ_decoder
   bool verify_trailer( const Pretty_print & pp ) const;
 
 public:
-  LZ_decoder( const File_header & header, Input_buffer & ibuf, const int odes )
+  LZ_decoder( const File_header & header, Range_decoder & rdec, const int outfd )
     :
     partial_data_pos( 0 ),
-    format_version( header.version ),
+    member_version( header.version() ),
     dictionary_size( header.dictionary_size() ),
     buffer_size( std::max( 65536, dictionary_size ) ),
     buffer( new uint8_t[buffer_size] ),
     pos( 0 ),
     stream_pos( 0 ),
-    crc_( 0xFFFFFFFF ),
-    odes_( odes ),
-    range_decoder( sizeof header, ibuf ),
-    literal_decoder()
+    crc_( 0xFFFFFFFFU ),
+    outfd_( outfd ),
+    range_decoder( rdec )
     { buffer[buffer_size-1] = 0; }	// prev_byte of first_byte
 
   ~LZ_decoder() { delete[] buffer; }
 
-  uint32_t crc() const throw() { return crc_ ^ 0xFFFFFFFF; }
+  uint32_t crc() const throw() { return crc_ ^ 0xFFFFFFFFU; }
   int decode_member( const Pretty_print & pp );
 
   long long member_position() const throw()