ref: 8561a843070582d48ef7f99e1138941c3509975f
dir: /sys/lib/ghostscript/gs_frsd.ps/
% Copyright (C) 2000 Aladdin Enterprises. All rights reserved.
%
% This software is provided AS-IS with no warranty, either express or
% implied.
%
% This software is distributed under license and may not be copied,
% modified or distributed except as expressly authorized under the terms
% of the license contained in the file LICENSE in this distribution.
%
% For more information about licensing, please refer to
% http://www.ghostscript.com/licensing/. For information on
% commercial licensing, go to http://www.artifex.com/licensing/ or
% contact Artifex Software, Inc., 101 Lucas Valley Road #110,
% San Rafael, CA 94903, U.S.A., +1(415)492-9861.
% $Id: gs_frsd.ps,v 1.9 2005/08/25 15:34:08 ray Exp $
% 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
10 dict exch {
% Stack: dict filters parms CloseSource contdict file
dup 64000 string readstring
3 index dup length 4 -1 roll put not { exit } if
} loop pop
% Concatenate the contents into one big string.
% Stack: dict filters parms CloseSource contdict
0 1 index { length exch pop add } forall
dup 65400 gt { .bytestring } { string } ifelse exch {
% Stack: dict filters parms CloseSource string index substring
exch 64000 mul exch 2 index 3 1 roll putinterval
} forall
% Now create the stream on the string.
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