From a6a7510c0e0fd8c39ea776dcc2c1d16fc6d8a024 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 7 Nov 2015 15:06:24 +0100 Subject: Merging upstream version 1.7~pre1. Signed-off-by: Daniel Baumann --- fast_encoder.h | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 fast_encoder.h (limited to 'fast_encoder.h') diff --git a/fast_encoder.h b/fast_encoder.h new file mode 100644 index 0000000..7265739 --- /dev/null +++ b/fast_encoder.h @@ -0,0 +1,82 @@ +/* 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 . + + 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 FLZ_encoder + { + struct LZ_encoder_base eb; + int 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]; + } + +int FLZe_longest_match_len( struct FLZ_encoder * const fe, int * const distance ); + +static inline bool FLZe_update_and_move( struct FLZ_encoder * const fe, int n ) + { + while( --n >= 0 ) + { + if( Mb_available_bytes( &fe->eb.mb ) >= 4 ) + { + int newpos; + fe->key4 = ( ( fe->key4 << 4 ) ^ fe->eb.mb.buffer[fe->eb.mb.pos+3] ) & + fe->eb.mb.key4_mask; + newpos = fe->eb.mb.prev_positions[fe->key4]; + fe->eb.mb.prev_positions[fe->key4] = fe->eb.mb.pos + 1; + fe->eb.mb.pos_array[fe->eb.mb.cyclic_pos] = newpos; + } + else fe->eb.mb.pos_array[fe->eb.mb.cyclic_pos] = 0; + if( !Mb_move_pos( &fe->eb.mb ) ) return false; + } + return true; + } + +static inline bool FLZe_init( struct FLZ_encoder * const fe, + const unsigned long long member_size ) + { + enum { before = 0, + dict_size = 65536, + /* bytes to keep in buffer after pos */ + after_size = max_match_len, + dict_factor = 16, + num_prev_positions23 = 0, + pos_array_factor = 1, + min_free_bytes = max_marker_size }; + + return LZeb_init( &fe->eb, before, 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 ); } -- cgit v1.2.3