plan9fox/sys/lib/ghostscript/gs_dscp.ps
2011-03-30 19:35:09 +03:00

119 lines
3.8 KiB
PostScript

% Copyright (C) 2000 Artifex Software Inc. 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_dscp.ps,v 1.6 2002/02/21 21:49:28 giles Exp $
% Postscript interface routines to DSC parser
/send_orientation { % <orientation> send_orientation -
% .parse_dsc_comments returns -1 for an Orientation key with an
% unrecognized value.
dup 0 ge {
<< /Orientation 2 index >> setpagedevice
} if pop
} bind def
% This dictionary contains local handlers for DSC comments.
% See header in zdscpars.c for more information.
% <dsc_dict> handler <dsc_dict>
/DSCparseprocs mark
/Orientation { dup /Orientation get send_orientation } bind
/PageOrientation { dup /PageOrientation .knownget { send_orientation }
{ dup /Orientation .knownget { send_orientation } if }
ifelse } bind
/Page { dup /Orientation .knownget { send_orientation } if } bind
/NOP { } bind
.dicttomark readonly def
% This procedure is called whenever a DSC comment is found by the interpreter
/do_parse_dsc false def
/parse_dsc { % <file> <DSC string> [<prev proc>]
% parse_dsc -
% Run any previously installed parser.
0 get dup null eq { pop } { 3 copy exec pop } ifelse
do_parse_dsc { % Check if this parser is enabled
currentglobal true setglobal % Go to global VM, save old state
3 1 roll % Put old VM state under <file> <string>
dsc_dict exch % <VM state> <file> <dict> <string>
.parse_dsc_comments % <VM state> <file> <dict> <DSC name>
4 -1 roll % Get old VM state from under <file> <dict> <DSC name>
setglobal % restore previous VM state
//DSCparseprocs exch .knownget { % Check DSC name against local handler list
exec % execute any local handler
} if
} if
pop pop % remove file, dict
} bind def
% Check whether the currently installed parser is the one defined in this file.
/.using_parse_dsc { % - .using_parse_dsc <proc> <using?>
currentuserparams /ProcessDSCComment get
dup null eq { pop {{//null} //parse_dsc exec} } if
dup length 3 eq {
dup dup length 1 sub get /parse_dsc load eq
} {
false
} ifelse
} bind def
% Establish a binding for dsc_dict.
userdict /dsc_dict null put
% - dsc_init -
/dsc_init { % Initialize DSC parser
currentglobal true setglobal
/dsc_dict 50 dict store % Size must be large enough for all DSC values
dsc_dict .initialize_dsc_parser
.using_parse_dsc {
% Already using this parser.
pop
} {
% Encapsulate the previous parser. We know it is in global VM:
% allocate the new one in global VM as well.
1 array astore
/parse_dsc load /exec load 3 array astore cvx readonly
<< /ProcessDSCComment 3 -1 roll >>
setuserparams
} ifelse
setglobal
/do_parse_dsc true def
} bind def
% Enable the DSC parser defined in this file.
% - enable_dsc -
/enable_dsc {
dsc_init
} bind def
% Disable the DSC parser defined in this file.
% - disable_dsc -
/disable_dsc {
% There might be another parser installed: if so, restore it.
% (If it has encapsulated our parser, we can't.)
.using_parse_dsc {
% Restore the parser we encapsulated.
0 get 0 get
currentglobal true setglobal exch
<< /ProcessDSCComment 3 -1 roll >>
exch setglobal setuserparams
} {
pop
} ifelse
% If we couldn't restore the old parser, at least disable ours.
/do_parse_dsc false def
} bind def