diff options
author | Reinhard Kotucha <reinhard.kotucha@web.de> | 2008-02-21 22:07:42 +0000 |
---|---|---|
committer | Reinhard Kotucha <reinhard.kotucha@web.de> | 2008-02-21 22:07:42 +0000 |
commit | f90099230db6de68f2285dca3d08174bda872f7a (patch) | |
tree | 48fbfd44b5c240a4430dd4a54b286de5f1102583 /Master/tlpkg/tlgs/lib/pdf_base.ps | |
parent | 2deea5f17b0505ffeb480154ace47e0a72863c97 (diff) |
tlpkg/tlgs: Subset of Ghostscript added.
git-svn-id: svn://tug.org/texlive/trunk@6709 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/tlpkg/tlgs/lib/pdf_base.ps')
-rw-r--r-- | Master/tlpkg/tlgs/lib/pdf_base.ps | 1006 |
1 files changed, 1006 insertions, 0 deletions
diff --git a/Master/tlpkg/tlgs/lib/pdf_base.ps b/Master/tlpkg/tlgs/lib/pdf_base.ps new file mode 100644 index 00000000000..fa82ba31612 --- /dev/null +++ b/Master/tlpkg/tlgs/lib/pdf_base.ps @@ -0,0 +1,1006 @@ +% Copyright (C) 1994-2006 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: pdf_base.ps 8022 2007-06-05 22:23:38Z giles $
+% pdf_base.ps
+% Basic parser for PDF reader.
+
+% This handles basic parsing of the file (including the trailer
+% and cross-reference table), as well as objects, object references,
+% streams, and name/number trees; it doesn't include any facilities for
+% making marks on the page.
+
+/.setlanguagelevel where { pop 2 .setlanguagelevel } if
+.currentglobal true .setglobal
+/pdfdict where { pop } { /pdfdict 100 dict def } ifelse
+pdfdict begin
+
+% Define the name interpretation dictionary for reading values.
+/valueopdict mark
+ (<<) cvn { mark } bind % don't push an actual mark!
+ (>>) cvn { { .dicttomark } stopped {
+ ( **** File has an unbalanced >> \(close dictionary\).\n)
+ pdfformaterror
+ } if
+ } bind
+ ([) cvn { mark } bind % ditto
+ (]) cvn dup load
+% /true true % see .pdfexectoken below
+% /false false % ibid.
+% /null null % ibid.
+ /F dup cvx % see Objects section below
+ /R dup cvx % see Objects section below
+ /stream dup cvx % see Streams section below
+.dicttomark readonly def
+
+% ------ Utilities ------ %
+
+% Define a scratch string. The PDF language definition says that
+% no line in a PDF file can exceed 255 characters, but this string
+% is also used to search for %PDF-, which needs 1024 characters.
+/pdfstring 1024 string def
+
+% Read the previous line of a file. If we aren't at a line boundary,
+% read the line containing the current position.
+% Skip any blank lines.
+/prevline % - prevline <startpos> <substring>
+ { PDFfile fileposition dup () pdfstring
+ 2 index 257 sub 0 .max PDFfile exch setfileposition
+ { % Stack: initpos linepos line string
+ PDFfile fileposition
+ PDFfile 2 index readline pop
+ dup length 0 gt
+ { 3 2 roll 5 -2 roll pop pop 2 index }
+ { pop }
+ ifelse
+ % Stack: initpos linepos line string startpos
+ PDFfile fileposition 5 index ge { exit } if
+ pop
+ }
+ loop pop pop 3 -1 roll pop
+ } bind def
+
+% Handle the PDF 1.2 #nn escape convention when reading from a file.
+% This should eventually be done in C.
+/.pdffixname { % <execname> .pdffixname <execname'>
+ PDFversion 1.2 ge {
+ dup .namestring (#) search {
+ name#escape cvn exch pop
+ } {
+ pop
+ } ifelse
+ } if
+} bind def
+/name#escape % <post> <(#)> <pre> name#escape <string>
+{ exch pop
+ 1 index 2 () /SubFileDecode filter dup (x) readhexstring
+ % Stack: post pre stream char t/f
+ not { % tolerate, but complain about bad syntax
+ pop closefile (#) concatstrings exch
+ ( **** Warning: Invalid hex following '#' name escape, using literal '#' in name.\n)
+ pdfformaterror
+ } {
+ exch closefile concatstrings
+ exch 2 1 index length 2 sub getinterval
+ } ifelse
+ (#) search { name#escape } if concatstrings
+} bind def
+
+% Execute a file, interpreting its executable names in a given
+% dictionary. The name procedures may do whatever they want
+% to the operand stack.
+/.pdftokenerror { % <count> <opdict> <errtoken> .pdftokenerror -
+ BXlevel 0 le {
+ ( **** Unknown operator: ') pdfformaterror
+ dup =string cvs pdfformaterror
+ % Attempt a retry scan of the element after changing to PDFScanInvNum
+ << /PDFScanInvNum true >> setuserparams
+ =string cvs
+ token pop exch pop dup type
+ dup /integertype eq exch /realtype eq or {
+ exch pop exch pop
+ (', processed as number, value: ) pdfformaterror
+ dup =string cvs pdfformaterror (\n) pdfformaterror
+ << /PDFScanInvNum null >> setuserparams % reset to default scanning rules
+ false % suppress any stack cleanup
+ } {
+ % error was non-recoverable with modified scanning rules
+ ('\n) pdfformaterror
+ true
+ } ifelse
+ } {
+ true
+ } ifelse
+ { % clean up the operand stack if this was non-recoverable
+ pop pop count exch sub { pop } repeat % pop all the operands
+ } if
+} bind def
+/.pdfexectoken { % <count> <opdict> <exectoken> .pdfexectoken ?
+ PDFDEBUG {
+ pdfdict /PDFSTEPcount known not { pdfdict /PDFSTEPcount 1 .forceput } if
+ PDFSTEP {
+ pdfdict /PDFtokencount 2 copy .knownget { 1 add } { 1 } ifelse .forceput
+ PDFSTEPcount 1 gt {
+ pdfdict /PDFSTEPcount PDFSTEPcount 1 sub .forceput
+ } {
+ dup ==only
+ ( step # ) print PDFtokencount =only
+ ( ? ) print flush 1 false .outputpage
+ (%stdin) (r) file 255 string readline {
+ token {
+ exch pop pdfdict /PDFSTEPcount 3 -1 roll .forceput
+ } {
+ pdfdict /PDFSTEPcount 1 .forceput
+ } ifelse % token
+ } {
+ pop /PDFSTEP false def % EOF on stdin
+ } ifelse % readline
+ } ifelse % PDFSTEPcount > 1
+ } {
+ dup ==only () = flush
+ } ifelse % PDFSTEP
+ } if % PDFDEBUG
+ 2 copy .knownget {
+ exch pop exch pop exch pop exec
+ } {
+ % Normally, true, false, and null would appear in opdict
+ % and be treated as "operators". However, there is a
+ % special fast case in the PostScript interpreter for names
+ % that are defined in, and only in, systemdict and/or
+ % userdict: putting these three names in the PDF dictionaries
+ % destroys this property for them, slowing down their
+ % interpretation in all PostScript code. Therefore, we
+ % check for them explicitly here instead.
+ dup dup dup /true eq exch /false eq or exch /null eq or {
+ exch pop exch pop //systemdict exch get
+ } {
+ % Hackish fix to detect missing whitespace after "endobj". Yet another
+ % problem that (you guessed it!) Adobe Acrobat ignores silently
+ 256 string cvs (endobj) anchorsearch {
+ ( **** Missing whitespace after 'endobj'.\n) pdfformaterror
+ exch pop cvn get exch pop exec
+ } {
+ .pdftokenerror
+ } ifelse
+ } ifelse
+ } ifelse
+} bind def
+/.pdfrun { % <file> <opdict> .pdfrun -
+ % Construct a procedure with the stack depth, file and opdict
+ % bound into it.
+ 1 index cvlit count 2 sub 3 1 roll mark mark 5 2 roll
+ { % Stack: ..operands.. count opdict file
+ { token } stopped {
+ dup type /filetype eq { pop } if % pop the operand if it is restored
+ ( **** Error reading a content stream. The page may be incomplete.\n)
+ pdfformaterror
+ //false
+ } if {
+ dup type /nametype eq {
+ dup xcheck {
+ .pdfexectoken
+ } {
+ .pdffixname
+ exch pop exch pop PDFDEBUG {
+ PDFSTEPcount 1 le {
+ dup ==only ( ) print flush
+ } if
+ } if
+ } ifelse
+ } {
+ exch pop exch pop PDFDEBUG {
+ PDFSTEPcount 1 le {
+ dup ==only ( ) print flush
+ } if
+ } if
+ } ifelse
+ } {
+ (%%EOF) cvn cvx .pdfexectoken
+ } ifelse
+ }
+ aload pop .packtomark cvx
+ /loop cvx 2 packedarray cvx
+ { stopped /PDFsource } aload pop
+ PDFsource
+ { store { stop } if } aload pop .packtomark cvx
+ /PDFsource 3 -1 roll store exec
+} bind def
+
+% Execute a file, like .pdfrun, for a marking context.
+% This temporarily rebinds LocalResources and DefaultQstate.
+/.pdfruncontext { % <resdict> <file> <opdict> .pdfruncontext -
+ /.pdfrun load LocalResources DefaultQstate
+ /LocalResources 7 -1 roll store
+ /DefaultQstate qstate store
+ 3 .execn
+ /DefaultQstate exch store
+ /LocalResources exch store
+} bind def
+
+% Get the depth of the PDF operand stack. The caller sets pdfemptycount
+% before calling .pdfrun or .pdfruncontext. It is initially set by
+% pdf_main, and is also set by any routine which changes the operand
+% stack depth (currently .pdfpaintproc, although there are other callers
+% of .pdfrun{context} which have not been checked for opstack depth.
+/.pdfcount { % - .pdfcount <count>
+ count pdfemptycount sub
+} bind def
+
+% Read a token, but simply return false (no token read) in the case of an
+% error. This is messy because 'token' either may or may not pop its operand
+% if an error occurs, and because the return values are different depending
+% on whether the source is a file or a string.
+/token_nofail { % <file|string> token_nofail false
+ % <file> token_nofail <token> true
+ % <string> token_nofail <post> <token> true
+ null 1 index % stack: source null source
+ { token } .internalstopped { % stack: source null [source]
+ null ne { pop } if pop false
+ } { % stack: source null ([post] token true | false)
+ { 1 index null eq { 3 1 } { 4 2 } ifelse roll pop pop true }
+ { pop pop false }
+ ifelse
+ } ifelse
+} bind def
+
+% ================================ Objects ================================ %
+
+% Since we may have more than 64K objects, we have to use a 2-D array to
+% hold them (and the parallel Generations structure).
+/lshift 9 def
+/lnshift lshift neg def
+/lsubmask 1 lshift bitshift 1 sub def
+/lsublen lsubmask 1 add def
+/larray { % - larray <larray>
+ [ [] ]
+} bind def
+/lstring { % - lstring <lstring>
+ [ () ]
+} bind def
+/ltype { % <lseq> type <type>
+ 0 get type
+} bind def
+/lget { % <lseq> <index> lget <value>
+ dup //lsubmask and 3 1 roll //lnshift bitshift get exch get
+} bind def
+/lput { % <lseq> <index> <value> lput -
+ 3 1 roll
+ dup //lsubmask and 4 1 roll //lnshift bitshift get
+ 3 1 roll put
+} bind def
+/llength { % <lseq> llength <length>
+ dup length 1 sub dup //lshift bitshift
+ 3 1 roll get length add
+} bind def
+% lgrowto assumes newlength > llength(lseq)
+/growto { % <string/array> <length> growto <string'/array'>
+ 1 index type /stringtype eq { string } { array } ifelse
+ 2 copy copy pop exch pop
+} bind def
+/lgrowto { % <lseq> <newlength> lgrowto <lseq'>
+ dup //lsubmask add //lnshift bitshift dup 3 index length gt {
+ % Add more sub-arrays. Start by completing the last existing one.
+ % Stack: lseq newlen newtoplen
+ 3 -1 roll dup llength 1 sub //lsubmask or 1 add lgrowto
+ % Stack: newlen newtoplen lseq
+ [ exch aload pop
+ counttomark 2 add -1 roll % newtoplen
+ counttomark sub { dup 0 0 getinterval lsublen growto } repeat
+ dup 0 0 getinterval ] exch
+ } {
+ pop
+ } ifelse
+ % Expand the last sub-array.
+ 1 sub //lsubmask and 1 add
+ exch dup dup length 1 sub 2 copy
+ % Stack: newsublen lseq lseq len-1 lseq len-1
+ get 5 -1 roll growto put
+} bind def
+/lforall { % <lseq> <proc> lforall -
+ /forall cvx 2 packedarray cvx forall
+} bind def
+
+% We keep track of PDF objects using the following PostScript variables:
+%
+% Generations (lstring): Generations[N] holds 1+ the current
+% generation number for object number N. (As far as we can tell,
+% this is needed only for error checking.) For free objects,
+% Generations[N] is 0.
+%
+% Objects (larray): If object N is loaded, Objects[N] is the actual
+% object; otherwise, Objects[N] is an executable integer giving
+% the file offset of the object's location in the file. If
+% ObjectStream[N] is non-zero then Objects[N] contains the index
+% into the object stream instead of the file offset of the object.
+%
+% ObjectStream (larray): If object N is in an object stream then
+% ObjectStream[N] holds the object number of the object stream.
+% Otherwise ObjectStream[N] contains 0. If ObjectStream[N]
+% is non-zero then Objects[N] contains the index into the object
+% stream.
+%
+% GlobalObjects (dictionary): If object N has been resolved in
+% global VM, GlobalObjects[N] is the same as Objects[N]
+% (except that GlobalObjects itself is stored in global VM,
+% so the entry will not be deleted at the end of the page).
+%
+% IsGlobal (lstring): IsGlobal[N] = 1 iff object N was resolved in
+% global VM. This is an accelerator to avoid having to do a
+% dictionary lookup in GlobalObjects when resolving every object.
+
+% Initialize the PDF object tables.
+/initPDFobjects { % - initPDFobjects -
+ /ObjectStream larray def
+ /Objects larray def
+ /Generations lstring def
+ .currentglobal true .setglobal
+ /GlobalObjects 20 dict def
+ .setglobal
+ /IsGlobal lstring def
+} bind def
+
+% Grow the tables to a specified size.
+/growPDFobjects { % <minsize> growPDFobjects -
+ dup ObjectStream llength gt {
+ dup ObjectStream exch lgrowto /ObjectStream exch def
+ } if
+ dup Objects llength gt {
+ dup Objects exch lgrowto /Objects exch def
+ } if
+ dup Generations llength gt {
+ dup Generations exch lgrowto /Generations exch def
+ } if
+ dup IsGlobal llength gt {
+ dup IsGlobal exch lgrowto /IsGlobal exch def
+ } if
+ pop
+} bind def
+
+% We represent an unresolved object reference by a procedure of the form
+% {obj# gen# resolveR}. This is not a possible PDF object, because PDF has
+% no way to represent procedures. Since PDF in fact has no way to represent
+% any PostScript object that doesn't evaluate to itself, we can 'force'
+% a possibly indirect object painlessly with 'exec'.
+% Note that since we represent streams by executable dictionaries
+% (see below), we need both an xcheck and a type check to determine
+% whether an object has been resolved.
+/resolved? { % <object#> resolved? <value> true
+ % <object#> resolved? false
+ Objects 1 index lget dup xcheck { % Check if executable
+ dup type /integertype eq { % Check if an integer
+ % Check whether the object is in GlobalObjects.
+ pop IsGlobal 1 index lget 0 eq { % 0 --> Not in GlabalObjects
+ pop false % The object is not resolved
+ } { % The object is in GlobalObjects
+ % Update Objects from GlobalObjects
+ PDFDEBUG { (%Global=>local: ) print dup == } if
+ GlobalObjects 1 index get dup Objects 4 1 roll lput true
+ } ifelse
+ } { % Else object is executable but not integer
+ exch pop true % Therefore must be executable dict. (stream)
+ } ifelse
+ } { % Else object is not executable.
+ exch pop true % Therefore it must have been resolved.
+ } ifelse
+} bind def
+/oforce /exec load def
+/oget { % <array> <index> oget <object>
+ % <dict> <key> oget <object>
+ % Before release 6.20, this procedure stored the resolved
+ % object back into the referring slot. In order to support
+ % PDF linearization, we no longer do this.
+ get oforce
+} bind def
+/oforce_array { % <array> oforce_array <array>
+ [ exch { oforce } forall ]
+} bind def
+/oforce_elems { % <array> oforce_elems <first> ... <last>
+ { oforce } forall
+} bind def
+/oforce_recursive { % <any> oforce_recursive <any>
+ oforce dup type dup /arraytype eq {
+ pop [ exch { oforce_recursive } forall ]
+ } {
+ /dicttype eq {
+ << exch { oforce_recursive exch oforce exch } forall >>
+ } if
+ } ifelse
+} bind def
+
+% A null value in a dictionary is equivalent to an omitted key;
+% we must check for this specially.
+/knownoget { % <dict> <key> knownoget <value> true
+ % <dict> <key> knownoget false
+ % See oget above regarding this procedure.
+ .knownget {
+ oforce dup //null eq { pop //false } { //true } ifelse
+ } {
+ //false
+ } ifelse
+} bind def
+
+% PDF 1.1 defines a 'foreign file reference', but not its meaning.
+% Per the specification, we convert these to nulls.
+/F { % <file#> <object#> <generation#> F <object>
+ % Some PDF 1.1 files use F as a synonym for f!
+ .pdfcount 3 lt { f } { pop pop pop null } ifelse
+} bind def
+
+% Verify the generation number for a specified object
+% Note: The values in Generations is the generation number plus 1.
+% If the value in Generations is zero then the object is free.
+/checkgeneration { % <object#> <generation#> checkgeneration <object#> <OK>
+ Generations 2 index lget 1 sub 1 index eq { % If generation # match ...
+ pop true % Then return true
+ } { % Else not a match ...
+ QUIET not { % Create warning message if not QUIET
+ Generations 2 index lget 0 eq { % Check if object is free ...
+ ( **** Warning: reference to free object: )
+ 2 index =string cvs concatstrings ( ) concatstrings % put obj #
+ exch =string cvs concatstrings ( R\n) concatstrings % put gen #
+ } {
+ ( **** Warning: wrong generation: )
+ 2 index =string cvs concatstrings ( ) concatstrings % put obj #
+ exch =string cvs concatstrings % put gen #
+ (, xref gen#: ) concatstrings 1 index Generations % put xref gen #
+ exch lget 1 sub =string cvs concatstrings (\n) concatstrings
+ } ifelse
+ pdfformaterror % Output warning message
+ } { % Else QUIET ...
+ pop % Pop generation number
+ } ifelse
+ % We should return false for an incorrect generation number, however
+ % we are simply printing a warning and then returning true. This makes
+ % Ghostscript tolerant of of bad generation numbers.
+ true
+ } ifelse
+} bind def
+/R { % <object#> <generation#> R <object>
+ /resolveR cvx 3 packedarray cvx
+} bind def
+
+% If we encounter an object definition while reading sequentially,
+% we just store it away and keep going.
+/objopdict mark
+ valueopdict { } forall
+ /endobj dup cvx
+.dicttomark readonly def
+
+/obj { % <object#> <generation#> obj <object>
+ PDFfile objopdict .pdfrun
+} bind def
+
+/endobj { % <object#> <generation#> <object> endobj <object>
+ 3 1 roll
+ % Read the xref entry if we haven't yet done so.
+ % This is only needed for generation # checking.
+ 1 index resolved? {
+ pop
+ } if
+ checkgeneration {
+ % The only global objects we bother to save are
+ % (resource) dictionaries.
+ 1 index dup gcheck exch type /dicttype eq and {
+ PDFDEBUG { (%Local=>global: ) print dup == } if
+ GlobalObjects 1 index 3 index put
+ IsGlobal 1 index 1 put
+ } if
+ Objects exch 2 index lput
+ } {
+ pop pop null
+ } ifelse
+} bind def
+
+% When resolving an object reference in an object stream, we stop at
+% the end of file. Note: Objects in an object stream do not have either
+% a starting 'obj' or and ending 'endobj'.
+/resolveobjstreamopdict mark
+ valueopdict { } forall
+ (%%EOF) cvn { exit } bind
+.dicttomark readonly def
+
+% Note: This version of this function is not currently being used.
+% Resolve all objects in an object stream
+/resolveobjectstream { % <object stream #> resolveobjectstream -
+ PDFDEBUG { (%Resolving object stream: ) print } if
+ 0 resolveR % Get the objectstream dict, all objstrms use 0 as the gen #
+ dup /First get % Save location of first object onto the stack
+ 1 index /N get % Save number of objects onto the stack
+ 2 index false resolvestream % Convert stream dict into a stream
+ /ReusableStreamDecode filter % We need to be able to position stream
+ % Objectstreams begin with list of object numbers and locations
+ % Create two arrays to hold object numbers and stream location
+ 1 index array % Array for holding object number
+ 2 index array % Array for holding stream object location
+ % Get the object numbers and locations.
+ 0 1 5 index 1 sub { % Loop and collect obj # and locations
+ % Stack: objstreamdict First N objectstream [obj#] [loc] index
+ 2 index 1 index % Setup to put obj# into object number array
+ 5 index token pop put % Get stream, then get obj# and put into array
+ 1 index 1 index % Setup to put object loc into location array
+ 5 index token pop put % Get stream, get obj loc and put into array
+ pop % Remove loop index
+ } for
+ % Create a bytestring big enough for reading any object data
+ % Scan for the size of the largest object
+ 0 0 % Init max object size and previous location
+ 2 index { % Loop through all object locations
+ % Stack: ... maxsize prevloc currentloc
+ dup 4 1 roll % Save copy of object location into stack
+ exch sub % Object size = currentloc - prevloc
+ .max % Determine maximum object size
+ exch % Put max size under previous location
+ } forall
+ pop % Remove previous location
+ .bigstring % Create bytestring based upon max obj size
+ % Move to the start of the object data
+ 3 index 6 index % Get objectstream and start of first object
+ setfileposition % Move to the start of the data
+ % Read the data for all objects except the last. We do
+ % not know the size of the last object so we need to treat
+ % it as a special case.
+ 0 1 6 index 2 sub {
+ dup 4 index exch get % Get our current object number
+ % Stack: objstreamdict First N objectstream [obj#] [loc]
+ % bytestring loopindex object#
+ dup resolved? { % If we already have this object
+ (yyy) = pstack (yyy) = flush xxx
+ pop pop % Remove object and object number
+ 1 add 2 index exch get % Get location of next object
+ 6 index add 6 index exch % Form location of next object and get stream
+ setfileposition % Move to the start of the next object data
+ } { % Else this is a new object ...
+ % We are going to create a string for reading the object
+ 2 index 0 % use our working string
+ % Determine the size of the object
+ 5 index 4 index 1 add get % Get location of the next object
+ 6 index 5 index get % Get location of this object
+ sub % Size of object = next loc - this loc
+ getinterval % Create string for reading object
+ 6 index exch readstring pop % Read object
+ /ReusableStreamDecode filter % Convert string into a stream
+ resolveobjstreamopdict .pdfrun % Get PDF object
+ Objects exch 2 index exch lput % Put object into Objects array
+ pop pop % Remove object # and loop index
+ } ifelse
+ } for
+ pop pop % Remove our working string and loc array
+ % Now read the last object in the object stream. Since it
+ % is the last object, we can use the original stream and
+ % terminate when we hit the end of the stream
+ % Stack: objstreamdict First N objectstream [obj#]
+ 2 index 1 sub get % Get our current object number
+ dup resolved? not { % If we do not already have this object
+ exch % Get our object stream
+ resolveobjstreamopdict .pdfrun % Get PDF object
+ Objects exch 2 index exch lput % Put object into Objects array
+ } if
+ pop pop pop pop % Clear stack
+} bind def
+
+% Resolve all objects in an object stream
+/resolveobjectstream { % <object stream #> resolveobjectstream -
+ PDFDEBUG { (%Resolving object stream: ) print } if
+ 0 resolveR % Get the objectstream dict, all objstrms use 0 as the gen #
+ dup /Type get /ObjStm ne { % Verify type is object stream
+ ( **** Incorrect Type in object stream dictionary.\n) pdfformaterror
+ /resolveobjectstream cvx /typecheck signalerror
+ } if
+ dup /N get % Save number of objects onto the stack
+ 1 index false resolvestream % Convert stream dict into a stream
+ /ReusableStreamDecode filter % We need to be able to position stream
+ % Objectstreams begin with list of object numbers and locations
+ 1 index array % Create array for holding object number
+ % Get the object numbers
+ 0 1 4 index 1 sub { % Loop and collect obj numbers
+ % Stack: objstreamdict N PDFDEBUG objectstream [obj#] loopindex
+ 1 index 1 index % Setup to put obj# into object number array
+ 4 index token pop put % Get stream, then get obj# and put into array
+ 2 index token pop pop pop % Get stream, get obj loc and clear stack
+ } for
+ % Move to the start of the object data
+ 1 index 4 index /First get % Get objectstream and start of first object
+ setfileposition % Move to the start of the data
+ % We disable PDFDEBUG while reading the data stream. We will
+ % print the data later
+ PDFDEBUG /PDFDEBUG false def % Save PDFDEBUG and disable it while reading
+ % Read the data for all objects. We check to see if we get
+ % the number of objects that we expect.
+ % Stack: objstreamdict N objectstream [obj#] PDFDEBUG
+ mark 4 -1 roll % Get objectstream
+ count 5 index add % Determine stack depth with objects
+ /PDFObjectStkCount exch def
+ resolveobjstreamopdict .pdfrun % Get PDF objects
+ PDFObjectStkCount count ne { % Check stack depth
+ ( **** Incorrect object count in object stream.\n) pdfformaterror
+ /resolveobjectstream cvx /rangecheck signalerror
+ } if
+ % We have the object data
+ counttomark array astore % Put objects into an array
+ exch pop % Remove mark
+ exch /PDFDEBUG exch def % Restore PDFDEBUG flag
+ % Save the objects into Objects
+ 0 1 2 index length 1 sub { % Loop through all objects
+ % Stack: objstreamdict N [obj#] [objects] loopindex
+ dup 3 index exch get % Get our current object number
+ dup resolved? { % If we already have this object
+ pop pop % Remove object and object number
+ } { % Else if we do not have this object
+ PDFDEBUG { (%Resolving compressed object: [) print dup =only ( 0]) = } if
+ Objects exch 3 index % Put the object into Objects
+ 3 index get
+ PDFDEBUG { dup === flush } if
+ lput
+ } ifelse
+ pop % Remove loop index
+ } for
+ pop pop pop pop % Remove objstream, N, (obj#], and [objects]
+} bind def
+
+% When resolving an object reference, we stop at the endobj or endstream.
+/resolveopdict mark
+ valueopdict { } forall
+ /endstream { endobj exit } bind
+ /endobj { endobj exit } bind
+ % OmniForm generates PDF file with endobj missing in some
+ % objects. AR ignores this. So we have to do it too.
+ /obj { pop pop endobj exit } bind
+.dicttomark readonly def
+
+/resolveR { % <object#> <generation#> resolveR <object>
+ PDFDEBUG {
+ PDFSTEPcount 1 le {
+ (%Resolving: ) print 2 copy 2 array astore ==
+ } if
+ } if
+ 1 index resolved? { % If object has already been resolved ...
+ exch pop exch pop % then clear stack and return object
+ } { % Else if not resolved ...
+ PDFfile fileposition 3 1 roll % Save current file position
+ 1 index Objects exch lget % Get location of object from xref
+ 3 1 roll checkgeneration { % Verify the generation number
+ % Stack: savepos objpos obj#
+ ObjectStream 1 index lget dup 0 eq { % Check if obj in not an objstream
+ pop exch PDFoffset add PDFfile exch setfileposition
+ PDFfile token pop 2 copy ne
+ { ( **** Unrecoverable error in xref!\n) pdfformaterror
+ /resolveR cvx /rangecheck signalerror
+ }
+ if pop PDFfile token pop
+ PDFfile token pop /obj ne
+ { ( **** Unrecoverable error in xref!\n) pdfformaterror
+ /resolveR cvx /rangecheck signalerror
+ }
+ if
+ pdf_run_resolve % PDFfile resolveopdict .pdfrun
+ } { % Else the object is in an ObjectStream
+ % Process an objectstream object. We are going to resolve all
+ % of the objects in sthe stream and place them into the Objects
+ % array.
+ % Stack: savepos objpos obj# objectstream#
+ resolveobjectstream
+ resolved? { % If object has already been resolved ...
+ exch pop % Remove object pos from stack.
+ } {
+ pop pop null % Pop objpos and obj#, put null for object
+ } ifelse
+ } ifelse
+ } { % Else the generation number is wrong
+ % Don't cache if the generation # is wrong.
+ pop pop null % Pop objpos and obj#, put null for object
+ } ifelse % ifelse generation number is correct
+ exch PDFfile exch setfileposition % Return to original file position
+ } ifelse
+} bind def
+
+% ================================ Streams ================================ %
+
+% We represent a stream by an executable dictionary that contains,
+% in addition to the contents of the original stream dictionary:
+% /File - the file or string where the stream contents are stored,
+% if the stream is not an external one.
+% /FilePosition - iff File is a file, the position in the file
+% where the contents start.
+% /StreamKey - the key used to decrypt this stream, if any.
+% We do the real work of constructing the data stream only when the
+% contents are needed.
+
+% Construct a stream. The length is not reliable in the face of
+% different end-of-line conventions, but it's all we've got.
+%
+% PDF files are inconsistent about what may fall between the 'stream' keyword
+% and the actual stream data, and it appears that no one algorithm can
+% detect this reliably. We used to try to guess whether the file included
+% extraneous \r and/or \n characters, but we no longer attempt to do so,
+% especially since the PDF 1.2 specification states flatly that the only
+% legal terminators following the 'stream' keyword are \n or \r\n, both of
+% which are properly skipped and discarded by the token operator.
+% Unfortunately, this doesn't account for other whitespace characters that
+% may have preceded the EOL, such as spaces or tabs. Thus we back up one
+% character and scan until we find the \n terminator.
+/stream { % <dict> stream <modified_dict>
+ dup /Length oget 0 eq {
+ dup /Filter undef % don't confuse any filters that require data
+ } if
+ dup /F known dup PDFsource PDFfile eq or {
+ not {
+ dup /File PDFfile put
+ % make sure that we are just past the EOL \n character
+ PDFfile dup fileposition 1 sub setfileposition % back up one
+ { PDFfile read pop dup 13 eq {
+ % If there had been a \n, token would have advanced over it
+ % thus, if the terminator was \r, we have a format error!
+ ( **** Warning: stream operator not terminated by valid EOL.\n) pdfformaterror
+ pop exit % fileposition is OK (just past the \r).
+ } if
+ 10 eq { exit } if
+ } loop % scan past \n
+ dup /FilePosition PDFfile fileposition put
+ PDFDEBUG {
+ PDFSTEPcount 1 le {
+ (%FilePosition: ) print dup /FilePosition get ==
+ } if
+ } if
+ } if
+ % Some (bad) PDf files have invalid stream lengths. This causes problems
+ % if we reposition beyond the end of the file. So we compare the given
+ % length to number of bytes left in the file.
+ dup /Length oget
+ dup PDFfile bytesavailable lt { % compare to to bytes left in file
+ PDFfile fileposition % reposition to the end of stream
+ add PDFfile exch setfileposition
+ } {
+ pop % bad stream length - do not reposition.
+ % This will force a length warning below
+ } ifelse
+ } {
+ pop
+ % We're already reading from a stream, which we can't reposition.
+ % Capture the sub-stream contents in a string.
+ dup /Length oget string PDFsource exch readstring
+ not {
+ ( **** Warning: Unexpected EOF in stream!\n) pdfformaterror
+ /stream cvx /rangecheck signalerror
+ } if
+ 1 index exch /File exch put
+ } ifelse
+ PDFsource token_nofail not { null } if
+ dup /endobj eq {
+ % Another case that Acrobat Reader handles -- 'endobj' without 'endstream'.
+ ( **** Warning: stream missing 'endstream'.\n) pdfformaterror
+ pop /endstream % fake a valid endstream
+ } if
+ /endstream ne {
+ ( **** Warning: stream Length incorrect.\n) pdfformaterror
+ dup /Length undef % prevent the use of the incorrect length.
+ cvx endobj exit % exit from .pdfrun now.
+ } if
+ cvx
+} bind def
+/endstream {
+ exit
+} bind def
+
+% Contrary to the published PDF (1.3) specification, Acrobat Reader
+% accepts abbreviated filter names everywhere, not just for in-line images,
+% and some applications (notably htmldoc) rely on this.
+/unabbrevfilterdict mark
+ /AHx /ASCIIHexDecode /A85 /ASCII85Decode /CCF /CCITTFaxDecode
+ /DCT /DCTDecode /Fl /FlateDecode /LZW /LZWDecode /RL /RunLengthDecode
+.dicttomark readonly def
+
+% Extract and apply filters.
+/filterparms { % <dict> <DPkey> <Fkey> filterparms
+ % <dict> <parms> <filternames>
+ 2 index exch knownoget {
+ oforce_recursive
+ exch 2 index exch knownoget {
+ % Both filters and parameters.
+ oforce_recursive
+ exch dup type /nametype eq {
+ 1 array astore exch
+ dup type /arraytype ne { 1 array astore } if exch
+ } if
+ } {
+ % Filters, but no parameters.
+ //null exch
+ dup type /nametype eq { 1 array astore } if
+ } ifelse
+ } {
+ % No filters: ignore parameters, if any.
+ pop //null { }
+ } ifelse
+} bind def
+/filtername { % <filtername> filtername <filtername'>
+ //unabbrevfilterdict 1 index .knownget { exch pop } if
+ dup /Filter resourcestatus { pop pop } {
+ Repaired exch % this error is not the creator's fault
+ ( **** ERROR: Unable to process ) pdfformaterror
+ 64 string cvs pdfformaterror
+ ( data. Page will be missing data.\n) pdfformaterror
+ /Repaired exch store % restore the previous "Repaired" state
+ % provide a filter that returns EOF (no data)
+ /.EOFDecode
+ } ifelse
+} bind def
+/applyfilters { % <parms> <source> <filternames> applyfilters <stream>
+ 2 index null eq {
+ { filtername filter }
+ } {
+ { % Stack: parms source filtername
+ 2 index 0 oget dup null eq { pop } {
+ exch filtername dup /JBIG2Decode eq { exch jbig2cachectx exch } if
+ } ifelse filter
+ exch dup length 1 sub 1 exch getinterval exch
+ }
+ } ifelse forall exch pop
+} bind def
+
+% JBIG2 streams have an optional 'globals' stream obj for
+% sharing redundant data between page images. Here we resolve
+% that stream reference (if any) and run it through the decoder,
+% creating a special -jbig2globalctx- postscript object our
+% JBIG2Decode filter implementation looks for in the parm dict.
+/jbig2cachectx { % <parmdict> jbig2cachectx <parmdict>
+ dup /JBIG2Globals knownoget {
+ % make global ctx
+ PDFfile fileposition exch % resolvestream is not reentrant
+ true resolvestream % stack after: PDFfileposition -file-
+ % Read the data in a loop until EOF to so we can move the strings into a bytestring
+ [ { counttomark 1 add index 60000 string readstring not { exit } if } loop ]
+ exch pop 0 1 index { length add } forall % compute the total length
+ % now copy the data from the array of strings into a bytestring
+ .bytestring exch 0 exch { 3 copy putinterval length add } forall pop
+ .jbig2makeglobalctx
+ PDFfile 3 -1 roll setfileposition
+ 1 index exch
+ /.jbig2globalctx exch put
+ } if
+} bind def
+
+% When used with a PDF image dict, the JPXDecode filter needs to know
+% about any ColorSpace entries, since this overrides whatever is in
+% the image stream itself. We therefore propagate any such key into
+% a filter's DecodeParms.
+/jpxparmfix { % <streamdict> <readdata?> jpxparmfix <streamdict <readdata?>
+ 1 index /Filter .knownget
+ { /JPXDecode eq % we only need to do this for JPXDecode filters
+ % TODO: handle filter arrays
+ {
+ 1 index /ColorSpace knownoget {
+ 2 index /DecodeParms knownoget {
+ % insert in the existing DecodeParms dict
+ /ColorSpace 3 -1 roll put
+ }{
+ 1 dict % need to create a custom DecodeParms dict
+ dup /ColorSpace 4 -1 roll put
+ 2 index exch /DecodeParms exch put
+ } ifelse
+ } if
+ } if
+ } if
+} bind def
+
+% Resolve a stream dictionary to a PostScript stream.
+% Streams with no filters require special handling:
+% - Whether we are going to interpret the stream, or If we are just
+% going to read data from them, we impose a SubFileDecode filter
+% that reads just the requisite amount of data.
+% Note that, in general, resolving a stream repositions PDFfile.
+% Clients must save and restore the position of PDFfile themselves.
+/resolvestream { % <streamdict> <readdata?> resolvestream <stream>
+ jpxparmfix
+ 1 index /F knownoget {
+ % This stream is stored on an external file.
+ (r) file 3 -1 roll
+ /FDecodeParms /FFilter filterparms
+ % Stack: readdata? file dict parms filternames
+ 4 -1 roll exch
+ pdf_decrypt_stream
+ applyfilters
+ } {
+ exch
+ dup /Length knownoget { 0 eq } { //false } ifelse {
+ () 0 () /SubFileDecode filter
+ } {
+ dup /FilePosition .knownget {
+ 1 index /File get exch setfileposition
+ } if
+ % Stack: readdata? dict
+ /DecodeParms /Filter filterparms
+ % Stack: readdata? dict parms filternames
+ 2 index /File get exch
+ % Stack: readdata? dict parms file/string filternames
+ dup length 0 eq {
+ % All the PDF filters have EOD markers, but in this case
+ % there is no specified filter.
+ exch dup type /filetype eq 5 index or {
+ % Use length for any files or reading data from any source.
+ 3 index /Length knownoget not { 0 } if
+ } {
+ 0 % Otherwise length of 0 for whole string
+ } ifelse
+ 4 index /IDFlag known { pop } { () /SubFileDecode filter } ifelse
+ exch
+ pdf_decrypt_stream % add decryption if needed
+ pop exch pop
+ } {
+ % Stack: readdata? dict parms source filternames
+ exch 3 index /Length knownoget {
+ () /SubFileDecode filter
+ } if exch
+ pdf_decrypt_stream % add decryption if needed
+ applyfilters
+ } ifelse
+ } ifelse
+ } ifelse
+ % Stack: readdata? dict file
+ exch pop exch pop
+} bind def
+
+% ============================ Name/number trees ============================ %
+
+/nameoget { % <nametree> <key> nameoget <obj|null>
+ exch /Names exch .treeget
+} bind def
+
+/numoget { % <numtree> <key> numoget <obj|null>
+ exch /Nums exch .treeget
+} bind def
+
+/.treeget { % <key> <leafkey> <tree> .treeget <obj|null>
+ dup /Kids knownoget {
+ exch pop .branchget
+ } {
+ exch get .leafget
+ } ifelse
+} bind def
+
+/.branchget { % <key> <leafkey> <kids> .branchget <obj|null>
+ dup length 0 eq {
+ pop pop pop null
+ } {
+ dup length -1 bitshift 2 copy oget
+ % Stack: key leafkey kids mid kids[mid]
+ dup /Limits oget aload pop
+ % Stack: key leafkey kids mid kids[mid] min max
+ 6 index lt {
+ pop pop
+ 1 add 1 index length 1 index sub getinterval .branchget
+ } {
+ 5 index gt {
+ pop
+ 0 exch getinterval .branchget
+ } {
+ exch pop exch pop .treeget
+ } ifelse
+ } ifelse
+ } ifelse
+} bind def
+
+/.leafget { % <key> <pairs> .leafget <obj|null>
+ dup length 2 eq {
+ dup 0 get 2 index eq { 1 oget } { pop null } ifelse
+ exch pop
+ } {
+ dup length -1 bitshift -2 and 2 copy oget
+ % Stack: key pairs mid pairs[mid]
+ 3 index gt { 0 exch } { 1 index length 1 index sub } ifelse
+ getinterval .leafget
+ } ifelse
+} bind def
+
+end % pdfdict
+.setglobal
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