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% 
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% implied.
% 
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% 
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% http://www.ghostscript.com/licensing/. For information on
% commercial licensing, go to http://www.artifex.com/licensing/ or
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% San Rafael, CA  94903, U.S.A., +1(415)492-9861.

% $Id: gs_frsd.ps 8954 2008-08-08 04:22:38Z ray $
% Implementation of ReusableStreamDecode filter.
% This file must be loaded after gs_lev2.ps and gs_res.ps.

level2dict begin

% ------ ReusableStreamDecode filter ------ %

/.reusablestreamdecode {	% <source> <dict> .reusablestreamdecode <file>
				% <source> .reusablestreamdecode <file>
		% Collect the filter parameters.
  dup type /dicttype eq { 2 copy } { dup 0 dict } ifelse
  dup .rsdparams
		% Construct the filter pipeline.
		% The very first filter should use the value of CloseSource
		% from the RSD dictionary; all the others should have
		% CloseSource = true.
		% Stack: source dict filters parms
  2 index /CloseSource .knownget not { //false } if 5 -1 roll
		% Stack: dict filters parms CloseSource source
  0 1 5 index length 1 sub {
    4 index 1 index get
		% Stack: dict filters parms CloseSource source index filtname
    4 index //null eq {
      0 dict
    } {
      4 index 2 index get dup //null eq { pop } if
    } ifelse
    3 -1 roll pop exch filter
    exch pop //true exch		% set CloseSource for further filters
  } for
		% If AsyncRead is true, try to create the filter directly.
		% Stack: dict filters parms CloseSource source
  4 index /AsyncRead .knownget not { //false } if {
    1 index { .reusablestream } .internalstopped
  } {
    //null //true
  } ifelse {
    pop
		% No luck.  Read the entire contents of the stream now.
    dup type /filetype ne {
		% Make a stream from a procedure or string data source.
      0 () .subfiledecode
    } if
		% We must allocate the string in the same VM space as its
		% source, since the reusable stream must be allocated there.

    .currentglobal 1 index gcheck .setglobal exch
    currentpacking //false setpacking exch
       		% Stack: dict filters parms CloseSource oldglobal oldpacking file
    [ exch { dup 40000 string readstring not { exit } if exch } loop
      exch pop
    ]
              		% Stack: dict filters parms CloseSource oldglobal oldpacking [()...]
    3 1 roll setpacking setglobal
              		% Stack: dict filters parms CloseSource [()...]
    1 index .reusablestream
  } if
		% We created the stream successfully: clean up.
  4 { exch pop } repeat
  1 index type /dicttype eq { exch pop } if exch pop
} odef

filterdict /ReusableStreamDecode /.reusablestreamdecode load put

end			% level2dict