PDXTable

PDF XRef (cross reference) table. More...

Files
file	PDXTable.h

Data Structures
struct	PDXTable

Macros
#define	PDXTableGetTypeForID(table, id)   (PDXType)((table->xrefs)[id*table->width])
#define	PDXTableSetTypeForID(table, id, t)   *(PDXType*)&((table->xrefs)[id*table->width]) = t
#define	PDXTableIsIDFree(xtable, id)   (PDXTypeFreed == PDXTableGetTypeForID(xtable, id))

Typedefs
typedef unsigned char	PDXType
	The type representation of an XREF entry.

Enumerations
enum	PDXFormat { PDXTableFormatText = 0, PDXTableFormatBinary = 1 }
enum	{ PDXTypeFreed = 0, PDXTypeUsed = 1, PDXTypeComp = 2 }

Functions
PDOffset	PDXTableGetOffsetForID (PDXTableRef table, PDInteger obid)
void	PDXTableSetOffsetForID (PDXTableRef table, PDInteger obid, PDOffset offset)
PDInteger	PDXTableGetGenForID (PDXTableRef table, PDInteger obid)
void	PDXTableSetGenForID (PDXTableRef table, PDInteger obid, PDInteger gen)
PDBool	PDXTableFetchXRefs (PDParserRef parser)
PDBool	PDXTablePassoverXRefEntry (PDParserRef parser, pd_stack stack, PDBool includeTrailer)
PDBool	PDXTableInsert (PDParserRef parser)
PDArrayRef	PDXTableWEntry (PDXTableRef table)
void	PDXTableSetSizes (PDXTableRef table, unsigned char typeSize, unsigned char offsSize, unsigned char genSize)
void	PDXTableGrow (PDXTableRef table, PDSize cap)
PDSize	PDXTableDetermineObjectSize (PDXTableRef table, PDInteger obid)

Parser
typedef struct PDXTable *	PDXTableRef

Detailed Description

PDF XRef (cross reference) table.

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Data Structure Documentation

struct PDXTable

PDF XRef (cross reference) table

Data Fields
PDInteger	allocx
PDInteger	obid
	object containing this XRef, if binary (text XRefs are not proper objects)
char *	xrefs
	XRef entries stored as a chunk of memory.
PDXFormat	format
	Original format of this entry, which can be text (PDF 1.4-) or binary (PDF 1.5+). Internally, there is no difference to how the data is maintained, but Pajdeg will use the same format used in the original in its own output.
PDBool	linearized
	If set, unexpected XREF entries in the PDF are silently ignored by the parser.
PDSize	cap
	Capacity of the table's xrefs buffer, in entries.
PDSize	count
	Number of objects held by the XRef.
PDSize	pos
	Byte-wise position in the PDF where the XRef (and subsequent trailer, if text format) begins; reaching this point means the XRef ceases to apply.
PDXTableRef	prev
	previous (older) table (mostly debug related)
PDXTableRef	next
	next (newer) table (mostly debug related)
PDOffset	offsCap
	threshold for offsets using current offsSize
PDArrayRef	w
	The W entry, if set.
PDInteger *	nextOb
	Array of object id's succeeding the object for the given array index. I.e. if the file has 4 0 obj ... endobj 10 0 obj ... endobj, then next[4] == 10 because object 10 is directly below object 4. This array is NULL until the first call to PDXTableDetermineObjectSize is made.
unsigned char	typeSize
	type size, current implementation requires this to be 1
unsigned char	offsSize
	offset size
unsigned char	genSize
	gen ID size
unsigned char	typeAlign
	type align
unsigned char	offsAlign
	offset align
unsigned char	genAlign
	gen ID align
unsigned char	width
	width of table entry

Macro Definition Documentation

#define PDXTableGetTypeForID	(		table,
			id
	)		(PDXType)((table->xrefs)[id*table->width])

Get the type for the given object.

Parameters

xrefs	The XREF buffer
id	The object ID.

#define PDXTableIsIDFree	(		xtable,
			id
	)		(PDXTypeFreed == PDXTableGetTypeForID(xtable, id))

Get the type for the given object in the table.

Parameters

xtable	The PDXTableRef instance
id	The object ID. Set the type for the given object in the table.
xtable	The PDXTableRef instance
id	The object ID.
t	The new type. Get the offset for the given object in the table.
xtable	The PDXTableRef instance
id	The object ID. Get the generation number or object stream index for the given object in the table.
xtable	The PDXTableRef instance
id	The object ID. Determine if the object with given ID is free.
xtable	The PDXTableRef instance
id	The object ID.

#define PDXTableSetTypeForID	(		table,
			id,
			t
	)		*(PDXType*)&((table->xrefs)[id*table->width]) = t

Set the type for the given object.

Parameters

xrefs	The XREF buffer
id	The object ID.
t	The new type.

Typedef Documentation

typedef struct PDXTable* PDXTableRef

PDXTable

Enumeration Type Documentation

anonymous enum

An XREF entry's type, which is one of freed (unused), used, or compressed.

Compressed objects are located inside of an object stream.

Enumerator
PDXTypeFreed	Freed object ('f' for text format entries)
PDXTypeUsed	Used object ('n' for text format entries)
PDXTypeComp	Compressed object (no text format equivalent)

enum PDXFormat

The XREF format, which can be one of text or binary.

Text XREFs have the appearance

xref 3 0
000000029 00000 n
000000142 00000 n
000013023 65535 f

while binary XREFs are binary values stored in an object with /Type /XRefStm.

Enumerator
PDXTableFormatText	PDF-1.4 and below, using 20-byte leading zero space delimited entries.
PDXTableFormatBinary	PDX-1.5 and forward, using variable width object stream format.

Function Documentation

PDSize PDXTableDetermineObjectSize	(	PDXTableRef	table,
		PDInteger	obid
	)

Determine the number of bytes between the first character in "<num> <num> obj" of the given object until the first character in the "<num> <num> obj" of the succeeding object in the file.

Parameters

table	PDX table
obid	Object whose size should be determined

Returns

Size of object in bytes

PDBool PDXTableFetchXRefs

(

PDParserRef

parser

)

Set the offset for the object with the given ID to the given offset in the XREF table.

Parameters

xtable	The PDX table instance.
id	The object ID.
offs	The new offset. Read a PDFs XREF data by jumping to the end of the file, reading in the startxref value and jumping to every XREF defined via e.g. /Prev, reading the XREFs in as a series with defined domains (by byte).

Note

The master XREF (the one pointed to by the startxref offset) defines whether the output PDF uses text or binary format, regardless of what other entries happen to be formatted as.

Takes into account linearized PDFs.

Parameters

parser

The parser.

PDInteger PDXTableGetGenForID	(	PDXTableRef	table,
		PDInteger	obid
	)

Get the generation number or object stream index for the given object.

Parameters

xrefs	The XREF buffer
id	The object ID.

PDOffset PDXTableGetOffsetForID	(	PDXTableRef	table,
		PDInteger	obid
	)

Get the offset for the object with the given ID in the XREF table.

Parameters

table	The PDXTable instance.
obid	The object ID.

void PDXTableGrow	(	PDXTableRef	table,
		PDSize	cap
	)

Grow the xref table to accomodate the given cap.

PDBool PDXTableInsert

(

PDParserRef

parser

)

Insert the one and only XREF table.

Note

Pajdeg does not support multiple XREF tables in a single PDF. The only downside to this is that linearized PDFs are delinearized in Pajdeg. Support for linearized PDFs is planned.

Parameters

parser

The parser.

Returns

true if the insertion was successful.

PDBool PDXTablePassoverXRefEntry	(	PDParserRef	parser,
		pd_stack	stack,
		PDBool	includeTrailer
	)

Pass over an XREF entry in the input PDF.

Note

This is only called for text formatted XREF tables; binary XREF tables appear as regular objects with streams

Parameters

parser	The parser.
stack	The XREF header stack scanned in from the PDScanner.
includeTrailer	Whether the trailer should also be consumed, or whether scanning should end after the XREF offsets.

void PDXTableSetGenForID	(	PDXTableRef	table,
		PDInteger	obid,
		PDInteger	gen
	)

Debug Set the generation number / object stream index for the given object.

Parameters

xrefs	The XREF buffer
id	The object ID.
gen	The new value.

void PDXTableSetOffsetForID	(	PDXTableRef	table,
		PDInteger	obid,
		PDOffset	offset
	)

Set the offset for the object with the given ID to the given offset in the XREF table.

Parameters

table	The PDXTable instance.
obid	The object ID.
offset	The new offset.

void PDXTableSetSizes	(	PDXTableRef	table,
		unsigned char	typeSize,
		unsigned char	offsSize,
		unsigned char	genSize
	)

Set the type, offset, and gen sizes for the table.

PDArrayRef PDXTableWEntry

(

PDXTableRef

table

)

Get the W entry for the table.