mirror of
https://github.com/moparisthebest/Simba
synced 2024-12-23 07:48:50 -05:00
76 lines
1.7 KiB
ObjectPascal
76 lines
1.7 KiB
ObjectPascal
unit bzip2comn;
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interface
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const
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max_groups = 6;
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max_alpha_size = 258;
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max_code_len = 23;
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group_size = 50;
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iter_count = 4;
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max_selectors = 2+(900000 div group_size);
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mtfa_size = 4096;
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mtfl_size = 16;
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type
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TCardinal_array = array [0..899999] of Cardinal;
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PCardinal_array = ^TCardinal_array;
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PCardinal = ^Cardinal;
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Thuffarray = array[0..max_alpha_size] of Cardinal;
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Phuffarray = ^Thuffarray;
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{A bzip2 stream starts with this:}
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const bzip2_stream_magic='BZh';
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{Error codes for stream errorinfo.}
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const
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bzip2_bad_header_magic = 1;
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bzip2_bad_block_magic = 2;
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bzip2_endoffile = 3;
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bzip2_data_error = 4;
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procedure hb_create_decode_tables(var limit,base,perm:array of cardinal;
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var length:array of byte;
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minlen,maxlen:byte;alphasize:cardinal);
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implementation
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procedure hb_create_decode_tables(var limit,base,perm:array of cardinal;
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var length:array of byte;
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minlen,maxlen:byte;alphasize:cardinal);
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var pp,i,j,vec:cardinal;
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begin
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pp:=0;
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for i:=minlen to maxlen do
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for j:=0 to alphasize-1 do
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if length[j]=i then
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begin
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perm[pp]:=j;
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inc(pp);
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end;
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for i:=0 to max_code_len-1 do
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begin
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base[i]:=0;
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limit[i]:=0;
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end;
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for i:=0 to alphasize-1 do
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inc(base[length[i]+1]);
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for i:=1 to max_code_len-1 do
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inc(base[i],base[i-1]);
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vec:=0;
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for i:=minlen to maxlen do
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begin
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inc(vec,base[i+1]-base[i]);
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limit[i]:=vec-1;
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vec:=vec shl 1;
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end;
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for i:=minlen+1 to maxlen do
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base[i]:=((limit[i-1]+1) shl 1)-base[i];
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end;
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end. |