1 files changed, 70 insertions, 0 deletions
diff --git a/fast_encoder.h b/fast_encoder.h
new file mode 100644
index 0000000..54756bd
--- /dev/null
+++ b/fast_encoder.h
@@ -0,0 +1,70 @@
+/* Lzlib - Compression library for the lzip format
+   Copyright (C) 2009-2022 Antonio Diaz Diaz.
+
+   This library is free software. Redistribution and use in source and
+   binary forms, with or without modification, are permitted provided
+   that the following conditions are met:
+
+   1. Redistributions of source code must retain the above copyright
+   notice, this list of conditions, and the following disclaimer.
+
+   2. Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions, and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+   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.
+*/
+
+struct FLZ_encoder
+  {
+  struct LZ_encoder_base eb;
+  unsigned key4;			/* key made from latest 4 bytes */
+  };
+
+static inline void FLZe_reset_key4( struct FLZ_encoder * const fe )
+  {
+  int i;
+  fe->key4 = 0;
+  for( i = 0; i < 3 && i < Mb_available_bytes( &fe->eb.mb ); ++i )
+    fe->key4 = ( fe->key4 << 4 ) ^ fe->eb.mb.buffer[i];
+  }
+
+static inline bool FLZe_update_and_move( struct FLZ_encoder * const fe, int n )
+  {
+  struct Matchfinder_base * const mb = &fe->eb.mb;
+  while( --n >= 0 )
+    {
+    if( Mb_available_bytes( mb ) >= 4 )
+      {
+      fe->key4 = ( ( fe->key4 << 4 ) ^ mb->buffer[mb->pos+3] ) & mb->key4_mask;
+      mb->pos_array[mb->cyclic_pos] = mb->prev_positions[fe->key4];
+      mb->prev_positions[fe->key4] = mb->pos + 1;
+      }
+    else mb->pos_array[mb->cyclic_pos] = 0;
+    if( !Mb_move_pos( mb ) ) return false;
+    }
+  return true;
+  }
+
+static inline bool FLZe_init( struct FLZ_encoder * const fe,
+                              const unsigned long long member_size )
+  {
+  enum { before_size = 0,
+         dict_size = 65536,
+         /* bytes to keep in buffer after pos */
+         after_size = max_match_len,
+         dict_factor = 16,
+         min_free_bytes = max_marker_size,
+         num_prev_positions23 = 0,
+         pos_array_factor = 1 };
+
+  return LZeb_init( &fe->eb, before_size, dict_size, after_size, dict_factor,
+                    num_prev_positions23, pos_array_factor, min_free_bytes,
+                    member_size );
+  }
+
+static inline void FLZe_reset( struct FLZ_encoder * const fe,
+                               const unsigned long long member_size )
+  { LZeb_reset( &fe->eb, member_size ); }