// Copyright (c) 2005-2024 Jay Berkenbilt
//
// This file is part of qpdf.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Versions of qpdf prior to version 7 were released under the terms
// of version 2.0 of the Artistic License. At your option, you may
// continue to consider qpdf to be licensed under those terms. Please
// see the manual for additional information.
#ifndef QPDFOBJECTHANDLE_HH
#define QPDFOBJECTHANDLE_HH
#include <qpdf/Constants.h>
#include <qpdf/DLL.h>
#include <qpdf/Types.h>
#include <functional>
#include <map>
#include <memory>
#include <set>
#include <string>
#include <vector>
#include <qpdf/Buffer.hh>
#include <qpdf/InputSource.hh>
#include <qpdf/JSON.hh>
#include <qpdf/PointerHolder.hh> // unused -- remove in qpdf 12 (see #785)
#include <qpdf/QPDFObjGen.hh>
#include <qpdf/QPDFTokenizer.hh>
class Pipeline;
class QPDF;
class QPDF_Array;
class QPDF_Bool;
class QPDF_Dictionary;
class QPDF_InlineImage;
class QPDF_Integer;
class QPDF_Name;
class QPDF_Null;
class QPDF_Operator;
class QPDF_Real;
class QPDF_Reserved;
class QPDF_Stream;
class QPDF_String;
class QPDFObject;
class QPDFTokenizer;
class QPDFExc;
class Pl_QPDFTokenizer;
class QPDFMatrix;
class QPDFParser;
class QPDFObjectHandle
{
friend class QPDFParser;
public:
// This class is used by replaceStreamData. It provides an alternative way of associating
// stream data with a stream. See comments on replaceStreamData and newStream for additional
// details.
class QPDF_DLL_CLASS StreamDataProvider
{
public:
QPDF_DLL
StreamDataProvider(bool supports_retry = false);
QPDF_DLL
virtual ~StreamDataProvider();
// The implementation of this function must write stream data to the given pipeline. The
// stream data must conform to whatever filters are explicitly associated with the stream.
// QPDFWriter may, in some cases, add compression, but if it does, it will update the
// filters as needed. Every call to provideStreamData for a given stream must write the same
// data. Note that, when writing linearized files, qpdf will call your provideStreamData
// twice, and if it generates different output, you risk generating invalid output or having
// qpdf throw an exception. The object ID and generation passed to this method are those
// that belong to the stream on behalf of which the provider is called. They may be ignored
// or used by the implementation for indexing or other purposes. This information is made
// available just to make it more convenient to use a single StreamDataProvider object to
// provide data for multiple streams.
// A few things to keep in mind:
//
// * Stream data providers must not modify any objects since they may be called after some
// parts of the file have already been written.
//
// * Since qpdf may call provideStreamData multiple times when writing linearized files, if
// the work done by your stream data provider is slow or computationally intensive, you
// might want to implement your own cache.
//
// * Once you have called replaceStreamData, the original stream data is no longer directly
// accessible from the stream, but this is easy to work around by copying the stream to
// a separate QPDF object. The qpdf library implements this very efficiently without
// actually making a copy of the stream data. You can find examples of this pattern in
// some of the examples, including pdf-custom-filter.cc and pdf-invert-images.cc.
// Prior to qpdf 10.0.0, it was not possible to handle errors the way pipeStreamData does or
// to pass back success. Starting in qpdf 10.0.0, those capabilities have been added by
// allowing an alternative provideStreamData to be implemented. You must implement at least
// one of the versions of provideStreamData below. If you implement the version that
// supports retry and returns a value, you should pass true as the value of supports_retry
// in the base class constructor. This will cause the library to call that version of the
// method, which should also return a boolean indicating whether it ran without errors.
QPDF_DLL
virtual void provideStreamData(QPDFObjGen const& og, Pipeline* pipeline);
QPDF_DLL
virtual bool provideStreamData(
QPDFObjGen const& og, Pipeline* pipeline, bool suppress_warnings, bool will_retry);
QPDF_DLL virtual void provideStreamData(int objid, int generation, Pipeline* pipeline);
QPDF_DLL virtual bool provideStreamData(
int objid, int generation, Pipeline* pipeline, bool suppress_warnings, bool will_retry);
QPDF_DLL
bool supportsRetry();
private:
bool supports_retry;
};
// The TokenFilter class provides a way to filter content streams in a lexically aware fashion.
// TokenFilters can be attached to streams using the addTokenFilter or addContentTokenFilter
// methods or can be applied on the spot by filterPageContents. You may also use
// Pl_QPDFTokenizer directly if you need full control.
//
// The handleToken method is called for each token, including the eof token, and then handleEOF
// is called at the very end. Handlers may call write (or writeToken) to pass data downstream.
// Please see examples/pdf-filter-tokens.cc and examples/pdf-count-strings.cc for examples of
// using TokenFilters.
//
// Please note that when you call token.getValue() on a token of type tt_string or tt_name, you
// get the canonical, "parsed" representation of the token. For a string, this means that there
// are no delimiters, and for a name, it means that all escaping (# followed by two hex digits)
// has been resolved. qpdf's internal representation of a name includes the leading slash. As
// such, you can't write the value of token.getValue() directly to output that is supposed to be
// valid PDF syntax. If you want to do that, you need to call writeToken() instead, or you can
// retrieve the token as it appeared in the input with token.getRawValue(). To construct a new
// string or name token from a canonical representation, use
// QPDFTokenizer::Token(QPDFTokenizer::tt_string, "parsed-str") or
// QPDFTokenizer::Token(QPDFTokenizer::tt_name,
// "/Canonical-Name"). Tokens created this way won't have a PDF-syntax raw value, but you can
// still write them with writeToken(). Example:
// writeToken(QPDFTokenizer::Token(QPDFTokenizer::tt_name, "/text/plain"))
// would write `/text#2fplain`, and
// writeToken(QPDFTokenizer::Token(QPDFTokenizer::tt_string, "a\\(b")) would write `(a\(b)`.
class QPDF_DLL_CLASS TokenFilter
{
public:
QPDF_DLL
TokenFilter() = default;
QPDF_DLL
virtual ~TokenFilter() = default;
virtual void handleToken(QPDFTokenizer::Token const&) = 0;
QPDF_DLL
virtual void handleEOF();
class PipelineAccessor
{
friend class Pl_QPDFTokenizer;
private:
static void
setPipeline(TokenFilter* f, Pipeline* p)
{
f->setPipeline(p);
}
};
protected:
QPDF_DLL
void write(char const* data, size_t len);
QPDF_DLL
void write(std::string const& str);
QPDF_DLL
void writeToken(QPDFTokenizer::Token const&);
private:
QPDF_DLL_PRIVATE
void setPipeline(Pipeline*);
Pipeline* pipeline;
};
// This class is used by parse to decrypt strings when reading an object that contains encrypted
// strings.
class StringDecrypter
{
public:
QPDF_DLL
virtual ~StringDecrypter() = default;
virtual void decryptString(std::string& val) = 0;
};
// This class is used by parsePageContents. Callers must instantiate a subclass of this with
// handlers defined to accept QPDFObjectHandles that are parsed from the stream.
class QPDF_DLL_CLASS ParserCallbacks
{
public:
QPDF_DLL
virtual ~ParserCallbacks() = default;
// One of the handleObject methods must be overridden.
QPDF_DLL
virtual void handleObject(QPDFObjectHandle);
QPDF_DLL
virtual void handleObject(QPDFObjectHandle, size_t offset, size_t length);
virtual void handleEOF() = 0;
// Override this if you want to know the full size of the contents, possibly after
// concatenation of multiple streams. This is called before the first call to handleObject.
QPDF_DLL
virtual void contentSize(size_t);
protected:
// Implementors may call this method during parsing to terminate parsing early. This method
// throws an exception that is caught by parsePageContents, so its effect is immediate.
QPDF_DLL
void terminateParsing();
};
// Convenience object for rectangles
class Rectangle
{
public:
Rectangle() :
llx(0.0),
lly(0.0),
urx(0.0),
ury(0.0)
{
}
Rectangle(double llx, double lly, double urx, double ury) :
llx(llx),
lly(lly),
urx(urx),
ury(ury)
{
}
double llx;
double lly;
double urx;
double ury;
};
// Convenience object for transformation matrices. See also QPDFMatrix. Unfortunately we can't
// replace this with QPDFMatrix because QPDFMatrix's default constructor creates the identity
// transform matrix and this one is all zeroes.
class Matrix
{
public:
Matrix() :
a(0.0),
b(0.0),
c(0.0),
d(0.0),
e(0.0),
f(0.0)
{
}
Matrix(double a, double b, double c, double d, double e, double f) :
a(a),
b(b),
c(c),
d(d),
e(e),
f(f)
{
}
double a;
double b;
double c;
double d;
double e;
double f;
};
QPDF_DLL
QPDFObjectHandle() = default;
QPDF_DLL
QPDFObjectHandle(QPDFObjectHandle const&) = default;
QPDF_DLL
QPDFObjectHandle& operator=(QPDFObjectHandle const&) = default;
#ifdef QPDF_FUTURE
QPDF_DLL
QPDFObjectHandle(QPDFObjectHandle&&) = default;
QPDF_DLL
QPDFObjectHandle& operator=(QPDFObjectHandle&&) = default;
#endif
QPDF_DLL
inline bool isInitialized() const;
// This method returns true if the QPDFObjectHandle objects point to exactly the same underlying
// object, meaning that changes to one are reflected in the other, or "if you paint one, the
// other one changes color." This does not perform a structural comparison of the contents of
// the objects.
QPDF_DLL
bool isSameObjectAs(QPDFObjectHandle const&) const;
// Return type code and type name of underlying object. These are useful for doing rapid type
// tests (like switch statements) or for testing and debugging.
QPDF_DLL
qpdf_object_type_e getTypeCode();
QPDF_DLL
char const* getTypeName();
// Exactly one of these will return true for any initialized object. Operator and InlineImage
// are only allowed in content streams.
QPDF_DLL
bool isBool();
QPDF_DLL
bool isNull();
QPDF_DLL
bool isInteger();
QPDF_DLL
bool isReal();
QPDF_DLL
bool isName();
QPDF_DLL
bool isString();
QPDF_DLL
bool isOperator();
QPDF_DLL
bool isInlineImage();
QPDF_DLL
bool isArray();
QPDF_DLL
bool isDictionary();
QPDF_DLL
bool isStream();
QPDF_DLL
bool isReserved();
// True for objects that are direct nulls. Does not attempt to resolve objects. This is intended
// for internal use, but it can be used as an efficient way to check for nulls that are not
// indirect objects.
QPDF_DLL
bool isDirectNull() const;
// This returns true in addition to the query for the specific type for indirect objects.
QPDF_DLL
inline bool isIndirect() const;
// This returns true for indirect objects from a QPDF that has been destroyed. Trying unparse
// such an object will throw a logic_error.
QPDF_DLL
bool isDestroyed();
// True for everything except array, dictionary, stream, word, and inline image.
QPDF_DLL
bool isScalar();
// True if the object is a name object representing the provided name.
QPDF_DLL
bool isNameAndEquals(std::string const& name);
// True if the object is a dictionary of the specified type and subtype, if any.
QPDF_DLL
bool isDictionaryOfType(std::string const& type, std::string const& subtype = "");
// True if the object is a stream of the specified type and subtype, if any.
QPDF_DLL
bool isStreamOfType(std::string const& type, std::string const& subtype = "");
// Public factory methods
// Wrap an object in an array if it is not already an array. This is a helper for cases in which
// something in a PDF may either be a single item or an array of items, which is a common idiom.
QPDF_DLL
QPDFObjectHandle wrapInArray();
// Construct an object of any type from a string representation of the object. Throws QPDFExc
// with an empty filename and an offset into the string if there is an error. Any indirect
// object syntax (obj gen R) will cause a logic_error exception to be thrown. If
// object_description is provided, it will appear in the message of any QPDFExc exception thrown
// for invalid syntax. See also the global `operator ""_qpdf` defined below.
QPDF_DLL
static QPDFObjectHandle
parse(std::string const& object_str, std::string const& object_description = "");
// Construct an object of any type from a string representation of the object. Indirect object
// syntax (obj gen R) is allowed and will create indirect references within the passed-in
// context. If object_description is provided, it will appear in the message of any QPDFExc
// exception thrown for invalid syntax. Note that you can't parse an indirect object reference
// all by itself as parse will stop at the end of the first complete object, which will just be
// the first number and will report that there is trailing data at the end of the string.
QPDF_DLL
static QPDFObjectHandle
parse(QPDF* context, std::string const& object_str, std::string const& object_description = "");
// Construct an object as above by reading from the given InputSource at its current position
// and using the tokenizer you supply. Indirect objects and encrypted strings are permitted.
// This method was intended to be called by QPDF for parsing objects that are ready from the
// object's input stream.
QPDF_DLL
static QPDFObjectHandle parse(
std::shared_ptr<InputSource> input,
std::string const& object_description,
QPDFTokenizer&,
bool& empty,
StringDecrypter* decrypter,
QPDF* context);
// Return the offset where the object was found when parsed. A negative value means that the
// object was created without parsing. If the object is in a stream, the offset is from the
// beginning of the stream. Otherwise, the offset is from the beginning of the file.
QPDF_DLL
qpdf_offset_t getParsedOffset();
// Older method: stream_or_array should be the value of /Contents from a page object. It's more
// convenient to just call QPDFPageObjectHelper::parsePageContents on the page object, and error
// messages will also be more useful because the page object information will be known.
QPDF_DLL
static void parseContentStream(QPDFObjectHandle stream_or_array, ParserCallbacks* callbacks);
// When called on a stream or stream array that is some page's content streams, do the same as
// pipePageContents. This method is a lower level way to do what
// QPDFPageObjectHelper::pipePageContents does, but it allows you to perform this operation on a
// contents object that is disconnected from a page object. The description argument should
// describe the containing page and is used in error messages. The all_description argument is
// initialized to something that could be used to describe the result of the pipeline. It is the
// description amended with the identifiers of the underlying objects. Please note that if there
// is an array of content streams, p->finish() is called after each stream. If you pass a
// pipeline that doesn't allow write() to be called after finish(), you can wrap it in an
// instance of Pl_Concatenate and then call manualFinish() on the Pl_Concatenate pipeline at the
// end.
QPDF_DLL
void
pipeContentStreams(Pipeline* p, std::string const& description, std::string& all_description);
// As of qpdf 8, it is possible to add custom token filters to a stream. The tokenized stream
// data is passed through the token filter after all original filters but before content stream
// normalization if requested. This is a low-level interface to add it to a stream. You will
// usually want to call QPDFPageObjectHelper::addContentTokenFilter instead, which can be
// applied to a page object, and which will automatically handle the case of pages whose
// contents are split across multiple streams.
QPDF_DLL
void addTokenFilter(std::shared_ptr<TokenFilter> token_filter);
// Legacy helpers for parsing content streams. These methods are not going away, but newer code
// should call the correspond methods in QPDFPageObjectHelper instead. The specification and
// behavior of these methods are the same as the identically named methods in that class, but
// newer functionality will be added there.
QPDF_DLL
void parsePageContents(ParserCallbacks* callbacks);
QPDF_DLL
void filterPageContents(TokenFilter* filter, Pipeline* next = nullptr);
// See comments for QPDFPageObjectHelper::pipeContents.
QPDF_DLL
void pipePageContents(Pipeline* p);
QPDF_DLL
void addContentTokenFilter(std::shared_ptr<TokenFilter> token_filter);
// End legacy content stream helpers
// Called on a stream to filter the stream as if it were page contents. This can be used to
// apply a TokenFilter to a form XObject, whose data is in the same format as a content stream.
QPDF_DLL
void filterAsContents(TokenFilter* filter, Pipeline* next = nullptr);
// Called on a stream to parse the stream as page contents. This can be used to parse a form
// XObject.
QPDF_DLL
void parseAsContents(ParserCallbacks* callbacks);
// Type-specific factories
QPDF_DLL
static QPDFObjectHandle newNull();
QPDF_DLL
static QPDFObjectHandle newBool(bool value);
QPDF_DLL
static QPDFObjectHandle newInteger(long long value);
QPDF_DLL
static QPDFObjectHandle newReal(std::string const& value);
QPDF_DLL
static QPDFObjectHandle
newReal(double value, int decimal_places = 0, bool trim_trailing_zeroes = true);
// Note about name objects: qpdf's internal representation of a PDF name is a sequence of bytes,
// excluding the NUL character, and starting with a slash. Name objects as represented in the
// PDF specification can contain characters escaped with #, but such escaping is not of concern
// when calling QPDFObjectHandle methods not directly relating to parsing. For example,
// newName("/text/plain").getName() and parse("/text#2fplain").getName() both return
// "/text/plain", while newName("/text/plain").unparse() and parse("/text#2fplain").unparse()
// both return "/text#2fplain". When working with the qpdf API for creating, retrieving, and
// modifying objects, you want to work with the internal, canonical representation. For names
// containing alphanumeric characters, dashes, and underscores, there is no difference between
// the two representations. For a lengthy discussion, see
// https://github.com/qpdf/qpdf/discussions/625.
QPDF_DLL
static QPDFObjectHandle newName(std::string const& name);
QPDF_DLL
static QPDFObjectHandle newString(std::string const& str);
// Create a string encoded from the given utf8-encoded string appropriately encoded to appear in
// PDF files outside of content streams, such as in document metadata form field values, page
// labels, outlines, and similar locations. We try ASCII first, then PDFDocEncoding, then UTF-16
// as needed to successfully encode all the characters.
QPDF_DLL
static QPDFObjectHandle newUnicodeString(std::string const& utf8_str);
QPDF_DLL
static QPDFObjectHandle newOperator(std::string const&);
QPDF_DLL
static QPDFObjectHandle newInlineImage(std::string const&);
QPDF_DLL
static QPDFObjectHandle newArray();
QPDF_DLL
static QPDFObjectHandle newArray(std::vector<QPDFObjectHandle> const& items);
QPDF_DLL
static QPDFObjectHandle newArray(Rectangle const&);
QPDF_DLL
static QPDFObjectHandle newArray(Matrix const&);
QPDF_DLL
static QPDFObjectHandle newArray(QPDFMatrix const&);
QPDF_DLL
static QPDFObjectHandle newDictionary();
QPDF_DLL
static QPDFObjectHandle newDictionary(std::map<std::string, QPDFObjectHandle> const& items);
// Create an array from a rectangle. Equivalent to the rectangle form of newArray.
QPDF_DLL
static QPDFObjectHandle newFromRectangle(Rectangle const&);
// Create an array from a matrix. Equivalent to the matrix form of newArray.
QPDF_DLL
static QPDFObjectHandle newFromMatrix(Matrix const&);
QPDF_DLL
static QPDFObjectHandle newFromMatrix(QPDFMatrix const&);
// Note: new stream creation methods have were added to the QPDF class starting with
// version 11.2.0. The ones in this class are here for backward compatibility.
// Create a new stream and associate it with the given qpdf object. A subsequent call must be
// made to replaceStreamData() to provide data for the stream. The stream's dictionary may be
// retrieved by calling getDict(), and the resulting dictionary may be modified. Alternatively,
// you can create a new dictionary and call replaceDict to install it. From QPDF 11.2, you can
// call QPDF::newStream() instead.
QPDF_DLL
static QPDFObjectHandle newStream(QPDF* qpdf);
// Create a new stream and associate it with the given qpdf object. Use the given buffer as the
// stream data. The stream dictionary's /Length key will automatically be set to the size of the
// data buffer. If additional keys are required, the stream's dictionary may be retrieved by
// calling getDict(), and the resulting dictionary may be modified. This method is just a
// convenient wrapper around the newStream() and replaceStreamData(). It is a convenience
// methods for streams that require no parameters beyond the stream length. Note that you don't
// have to deal with compression yourself if you use QPDFWriter. By default, QPDFWriter will
// automatically compress uncompressed stream data. Example programs are provided that
// illustrate this. From QPDF 11.2, you can call QPDF::newStream()
// instead.
QPDF_DLL
static QPDFObjectHandle newStream(QPDF* qpdf, std::shared_ptr<Buffer> data);
// Create new stream with data from string. This method will create a copy of the data rather
// than using the user-provided buffer as in the std::shared_ptr<Buffer> version of newStream.
// From QPDF 11.2, you can call QPDF::newStream() instead.
QPDF_DLL
static QPDFObjectHandle newStream(QPDF* qpdf, std::string const& data);
// A reserved object is a special sentinel used for qpdf to reserve a spot for an object that is
// going to be added to the QPDF object. Normally you don't have to use this type since you can
// just call QPDF::makeIndirectObject. However, in some cases, if you have to create objects
// with circular references, you may need to create a reserved object so that you can have a
// reference to it and then replace the object later. Reserved objects have the special
// property that they can't be resolved to direct objects. This makes it possible to replace a
// reserved object with a new object while preserving existing references to them. When you are
// ready to replace a reserved object with its replacement, use QPDF::replaceReserved for this
// purpose rather than the more general QPDF::replaceObject. It is an error to try to write a
// QPDF with QPDFWriter if it has any reserved objects in it. From QPDF 11.4, you can call
// QPDF::newReserved() instead.
QPDF_DLL
static QPDFObjectHandle newReserved(QPDF* qpdf);
// Provide an owning qpdf and object description. The library does this automatically with
// objects that are read from the input PDF and with objects that are created programmatically
// and inserted into the QPDF as a new indirect object. Most end user code will not need to call
// this. If an object has an owning qpdf and object description, it enables qpdf to give
// warnings with proper context in some cases where it would otherwise raise exceptions. It is
// okay to add objects without an owning_qpdf to objects that have one, but it is an error to
// have a QPDF contain objects with owning_qpdf set to something else. To add objects from
// another qpdf, use copyForeignObject instead.
QPDF_DLL
void setObjectDescription(QPDF* owning_qpdf, std::string const& object_description);
QPDF_DLL
bool hasObjectDescription();
// Accessor methods
//
// (Note: this comment is referenced in qpdf-c.h and the manual.)
//
// In PDF files, objects have specific types, but there is nothing that prevents PDF files from
// containing objects of types that aren't expected by the specification.
//
// There are two flavors of accessor methods:
//
// * getSomethingValue() returns the value and issues a type warning if the type is incorrect.
//
// * getValueAsSomething() returns false if the value is the wrong type. Otherwise, it returns
// true and initializes a reference of the appropriate type. These methods never issue type
// warnings.
//
// The getSomethingValue() accessors and some of the other methods expect objects of a
// particular type. Prior to qpdf 8, calling an accessor on a method of the wrong type, such as
// trying to get a dictionary key from an array, trying to get the string value of a number,
// etc., would throw an exception, but since qpdf 8, qpdf issues a warning and recovers using
// the following behavior:
//
// * Requesting a value of the wrong type (int value from string, array item from a scalar or
// dictionary, etc.) will return a zero-like value for that type: false for boolean, 0 for
// number, the empty string for string, or the null object for an object handle.
//
// * Accessing an array item that is out of bounds will return a null object.
//
// * Attempts to mutate an object of the wrong type (e.g., attempting to add a dictionary key to
// a scalar or array) will be ignored.
//
// When any of these fallback behaviors are used, qpdf issues a warning. Starting in qpdf 10.5,
// these warnings have the error code qpdf_e_object. Prior to 10.5, they had the error code
// qpdf_e_damaged_pdf. If the QPDFObjectHandle is associated with a QPDF object (as is the case
// for all objects whose origin was a PDF file), the warning is issued using the normal warning
// mechanism (as described in QPDF.hh), making it possible to suppress or otherwise detect them.
// If the QPDFObjectHandle is not associated with a QPDF object (meaning it was created
// programmatically), an exception will be thrown.
//
// The way to avoid getting any type warnings or exceptions, even when working with malformed
// PDF files, is to always check the type of a QPDFObjectHandle before accessing it (for
// example, make sure that isString() returns true before calling getStringValue()) and to
// always be sure that any array indices are in bounds.
//
// For additional discussion and rationale for this behavior, see the section in the QPDF manual
// entitled "Object Accessor Methods".
// Methods for bool objects
QPDF_DLL
bool getBoolValue();
QPDF_DLL
bool getValueAsBool(bool&);
// Methods for integer objects. Note: if an integer value is too big (too far away from zero in
// either direction) to fit in the requested return type, the maximum or minimum value for that
// return type may be returned. For example, on a system with 32-bit int, a numeric object with
// a value of 2^40 (or anything too big for 32 bits) will be returned as INT_MAX.
QPDF_DLL
long long getIntValue();
QPDF_DLL
bool getValueAsInt(long long&);
QPDF_DLL
int getIntValueAsInt();
QPDF_DLL
bool getValueAsInt(int&);
QPDF_DLL
unsigned long long getUIntValue();
QPDF_DLL
bool getValueAsUInt(unsigned long long&);
QPDF_DLL
unsigned int getUIntValueAsUInt();
QPDF_DLL
bool getValueAsUInt(unsigned int&);
// Methods for real objects
QPDF_DLL
std::string getRealValue();
QPDF_DLL
bool getValueAsReal(std::string&);
// Methods that work for both integer and real objects
QPDF_DLL
bool isNumber();
QPDF_DLL
double getNumericValue();
QPDF_DLL
bool getValueAsNumber(double&);
// Methods for name objects. The returned name value is in qpdf's canonical form with all
// escaping resolved. See comments for newName() for details.
QPDF_DLL
std::string getName();
QPDF_DLL
bool getValueAsName(std::string&);
// Methods for string objects
QPDF_DLL
std::string getStringValue();
QPDF_DLL
bool getValueAsString(std::string&);
// If a string starts with the UTF-16 marker, it is converted from UTF-16 to UTF-8. Otherwise,
// it is treated as a string encoded with PDF Doc Encoding. PDF Doc Encoding is identical to
// ISO-8859-1 except in the range from 0200 through 0240, where there is a mapping of characters
// to Unicode. QPDF versions prior to version 8.0.0 erroneously left characters in that range
// unmapped.
QPDF_DLL
std::string getUTF8Value();
QPDF_DLL
bool getValueAsUTF8(std::string&);
// Methods for content stream objects
QPDF_DLL
std::string getOperatorValue();
QPDF_DLL
bool getValueAsOperator(std::string&);
QPDF_DLL
std::string getInlineImageValue();
QPDF_DLL
bool getValueAsInlineImage(std::string&);
// Methods for array objects; see also name and array objects.
// Return an object that enables iteration over members. You can do
//
// for (auto iter: obj.aitems())
// {
// // iter is an array element
// }
class QPDFArrayItems;
QPDF_DLL
QPDFArrayItems aitems();
QPDF_DLL
int getArrayNItems();
QPDF_DLL
QPDFObjectHandle getArrayItem(int n);
// Note: QPDF arrays internally optimize memory for arrays containing lots of nulls. Calling
// getArrayAsVector may cause a lot of memory to be allocated for very large arrays with lots of
// nulls.
QPDF_DLL
std::vector<QPDFObjectHandle> getArrayAsVector();
QPDF_DLL
bool isRectangle();
// If the array is an array of four numeric values, return as a rectangle. Otherwise, return the
// rectangle [0, 0, 0, 0]
QPDF_DLL
Rectangle getArrayAsRectangle();
QPDF_DLL
bool isMatrix();
// If the array is an array of six numeric values, return as a matrix. Otherwise, return the
// matrix [1, 0, 0, 1, 0, 0]
QPDF_DLL
Matrix getArrayAsMatrix();
// Methods for dictionary objects. In all dictionary methods, keys are specified/represented as
// canonical name strings starting with a leading slash and not containing any PDF syntax
// escaping. See comments for getName() for details.
// Return an object that enables iteration over members. You can do
//
// for (auto iter: obj.ditems())
// {
// // iter.first is the key
// // iter.second is the value
// }
class QPDFDictItems;
QPDF_DLL
QPDFDictItems ditems();
// Return true if key is present. Keys with null values are treated as if they are not present.
// This is as per the PDF spec.
QPDF_DLL
bool hasKey(std::string const&);
// Return the value for the key. If the key is not present, null is returned.
QPDF_DLL
QPDFObjectHandle getKey(std::string const&);
// If the object is null, return null. Otherwise, call getKey(). This makes it easier to access
// lower-level dictionaries, as in
// auto font = page.getKeyIfDict("/Resources").getKeyIfDict("/Font");
QPDF_DLL
QPDFObjectHandle getKeyIfDict(std::string const&);
// Return all keys. Keys with null values are treated as if they are not present. This is as
// per the PDF spec.
QPDF_DLL
std::set<std::string> getKeys();
// Return dictionary as a map. Entries with null values are included.
QPDF_DLL
std::map<std::string, QPDFObjectHandle> getDictAsMap();
// Methods for name and array objects. The name value is in qpdf's canonical form with all
// escaping resolved. See comments for newName() for details.
QPDF_DLL
bool isOrHasName(std::string const&);
// Make all resources in a resource dictionary indirect. This just goes through all entries of
// top-level subdictionaries and converts any direct objects to indirect objects. This can be
// useful to call before mergeResources if it is going to be called multiple times to prevent
// resources from being copied multiple times.
QPDF_DLL
void makeResourcesIndirect(QPDF& owning_qpdf);
// Merge resource dictionaries. If the "conflicts" parameter is provided, conflicts in
// dictionary subitems are resolved, and "conflicts" is initialized to a map such that
// conflicts[resource_type][old_key] == [new_key]
//
// See also makeResourcesIndirect, which can be useful to call before calling this.
//
// This method does nothing if both this object and the other object are not dictionaries.
// Otherwise, it has following behavior, where "object" refers to the object whose method is
// invoked, and "other" refers to the argument:
//
// * For each key in "other" whose value is an array:
// * If "object" does not have that entry, shallow copy it.
// * Otherwise, if "object" has an array in the same place, append to that array any objects
// in "other"'s array that are not already present.
// * For each key in "other" whose value is a dictionary:
// * If "object" does not have that entry, shallow copy it.
// * Otherwise, for each key in the subdictionary:
// * If key is not present in "object"'s entry, shallow copy it if direct or just add it if
// indirect.
// * Otherwise, if conflicts are being detected:
// * If there is a key (oldkey) already in the dictionary that points to the same indirect
// destination as key, indicate that key was replaced by oldkey. This would happen if
// these two resource dictionaries have previously been merged.
// * Otherwise pick a new key (newkey) that is unique within the resource dictionary,
// store that in the resource dictionary with key's destination as its destination, and
// indicate that key was replaced by newkey.
//
// The primary purpose of this method is to facilitate merging of resource dictionaries that are
// supposed to have the same scope as each other. For example, this can be used to merge a form
// XObject's /Resources dictionary with a form field's /DR or to merge two /DR dictionaries. The
// "conflicts" parameter may be previously initialized. This method adds to whatever is already
// there, which can be useful when merging with multiple things.
QPDF_DLL
void mergeResources(
QPDFObjectHandle other,
std::map<std::string, std::map<std::string, std::string>>* conflicts = nullptr);
// Get all resource names from a resource dictionary. If this object is a dictionary, this
// method returns a set of all the keys in all top-level subdictionaries. For resources
// dictionaries, this is the collection of names that may be referenced in the content stream.
QPDF_DLL
std::set<std::string> getResourceNames();
// Find a unique name within a resource dictionary starting with a given prefix. This method
// works by appending a number to the given prefix. It searches starting with min_suffix and
// sets min_suffix to selected value upon return. This can be used to increase efficiency if
// adding multiple items with the same prefix. (Why doesn't it set min_suffix to the next
// number? Well, maybe you aren't going to actually use the name it returns.) If you are calling
// this multiple times on the same resource dictionary, you can initialize resource_names by
// calling getResourceNames(), incrementally update it as you add resources, and keep passing it
// in so that getUniqueResourceName doesn't have to traverse the resource dictionary each time
// it's called.
QPDF_DLL
std::string getUniqueResourceName(
std::string const& prefix,
int& min_suffix,
std::set<std::string>* resource_names = nullptr);
// A QPDFObjectHandle has an owning QPDF if it is associated with ("owned by") a specific QPDF
// object. Indirect objects always have an owning QPDF. Direct objects that are read from the
// input source will also have an owning QPDF. Programmatically created objects will only have
// one if setObjectDescription was called.
//
// When the QPDF object that owns an object is destroyed, the object is changed into a null, and
// its owner is cleared. Therefore you should not retain the value of an owning QPDF beyond the
// life of the QPDF. If in doubt, ask for it each time you need it.
// getOwningQPDF returns a pointer to the owning QPDF is the object has one. Otherwise, it
// returns a null pointer. Use this when you are able to handle the case of an object that
// doesn't have an owning QPDF.
QPDF_DLL
QPDF* getOwningQPDF() const;
// getQPDF, new in qpdf 11, returns a reference owning QPDF. If there is none, it throws a
// runtime_error. Use this when you know the object has to have an owning QPDF, such as when
// it's a known indirect object. Since streams are always indirect objects, this method can be
// used safely for streams. If error_msg is specified, it will be used at the contents of the
// runtime_error if there is now owner.
QPDF_DLL
QPDF& getQPDF(std::string const& error_msg = "") const;
// Create a shallow copy of an object as a direct object, but do not traverse across indirect
// object boundaries. That means that, for dictionaries and arrays, any keys or items that were
// indirect objects will still be indirect objects that point to the same place. In the
// strictest sense, this is not a shallow copy because it recursively descends arrays and
// dictionaries; it just doesn't cross over indirect objects. See also unsafeShallowCopy(). You
// can't copy a stream this way. See copyStream() instead.
QPDF_DLL
QPDFObjectHandle shallowCopy();
// Create a true shallow copy of an array or dictionary, just copying the immediate items
// (array) or keys (dictionary). This is "unsafe" because, if you *modify* any of the items in
// the copy, you are modifying the original, which is almost never what you want. However, if
// your intention is merely to *replace* top-level items or keys and not to modify lower-level
// items in the copy, this method is much faster than shallowCopy().
QPDF_DLL
QPDFObjectHandle unsafeShallowCopy();
// Create a copy of this stream. The new stream and the old stream are independent: after the
// copy, either the original or the copy's dictionary or data can be modified without affecting
// the other. This uses StreamDataProvider internally, so no unnecessary copies of the stream's
// data are made. If the source stream's data is already being provided by a StreamDataProvider,
// the new stream will use the same one, so you have to make sure your StreamDataProvider can
// handle that case. But if you're already using a StreamDataProvider, you probably don't need
// to call this method.
QPDF_DLL
QPDFObjectHandle copyStream();
// Mutator methods.
// Since qpdf 11: for mutators that may add or remove an item, there are additional versions
// whose names contain "AndGet" that return the added or removed item. For example:
//
// auto new_dict = dict.replaceKeyAndGetNew(
// "/New", QPDFObjectHandle::newDictionary());
//
// auto old_value = dict.replaceKeyAndGetOld(
// "/New", "(something)"_qpdf);
// Recursively copy this object, making it direct. An exception is thrown if a loop is detected.
// With allow_streams true, keep indirect object references to streams. Otherwise, throw an
// exception if any sub-object is a stream. Note that, when allow_streams is true and a stream
// is found, the resulting object is still associated with the containing qpdf. When
// allow_streams is false, the object will no longer be connected to the original QPDF object
// after this call completes successfully.
QPDF_DLL
void makeDirect(bool allow_streams = false);
// Mutator methods for array objects
QPDF_DLL
void setArrayItem(int, QPDFObjectHandle const&);
QPDF_DLL
void setArrayFromVector(std::vector<QPDFObjectHandle> const& items);
// Insert an item before the item at the given position ("at") so that it has that position
// after insertion. If "at" is equal to the size of the array, insert the item at the end.
QPDF_DLL
void insertItem(int at, QPDFObjectHandle const& item);
// Like insertItem but return the item that was inserted.
QPDF_DLL
QPDFObjectHandle insertItemAndGetNew(int at, QPDFObjectHandle const& item);
// Append an item to an array.
QPDF_DLL
void appendItem(QPDFObjectHandle const& item);
// Append an item, and return the newly added item.
QPDF_DLL
QPDFObjectHandle appendItemAndGetNew(QPDFObjectHandle const& item);
// Remove the item at that position, reducing the size of the array by one.
QPDF_DLL
void eraseItem(int at);
// Erase and item and return the item that was removed.
QPDF_DLL
QPDFObjectHandle eraseItemAndGetOld(int at);
// Mutator methods for dictionary objects
// Replace value of key, adding it if it does not exist. If value is null, remove the key.
QPDF_DLL
void replaceKey(std::string const& key, QPDFObjectHandle const& value);
// Replace value of key and return the value.
QPDF_DLL
QPDFObjectHandle replaceKeyAndGetNew(std::string const& key, QPDFObjectHandle const& value);
// Replace value of key and return the old value, or null if the key was previously not present.
QPDF_DLL
QPDFObjectHandle replaceKeyAndGetOld(std::string const& key, QPDFObjectHandle const& value);
// Remove key, doing nothing if key does not exist.
QPDF_DLL
void removeKey(std::string const& key);
// Remove key and return the old value. If the old value didn't exist, return a null object.
QPDF_DLL
QPDFObjectHandle removeKeyAndGetOld(std::string const& key);
// ABI: Remove in qpdf 12
[[deprecated("use replaceKey -- it does the same thing")]] QPDF_DLL void
replaceOrRemoveKey(std::string const& key, QPDFObjectHandle const&);
// Methods for stream objects
QPDF_DLL
QPDFObjectHandle getDict();
// By default, or if true passed, QPDFWriter will attempt to filter a stream based on decode
// level, whether compression is enabled, and its ability to filter. Passing false will prevent
// QPDFWriter from attempting to filter the stream even if it can. This includes both decoding
// and compressing. This makes it possible for you to prevent QPDFWriter from uncompressing and
// recompressing a stream that it knows how to operate on for any application-specific reason,
// such as that you have already optimized its filtering. Note that this doesn't affect any
// other ways to get the stream's data, such as pipeStreamData or getStreamData.
QPDF_DLL
void setFilterOnWrite(bool);
QPDF_DLL
bool getFilterOnWrite();
// If addTokenFilter has been called for this stream, then the original data should be
// considered to be modified. This means we should avoid optimizations such as not filtering a
// stream that is already compressed.
QPDF_DLL
bool isDataModified();
// Returns filtered (uncompressed) stream data. Throws an exception if the stream is filtered
// and we can't decode it.
QPDF_DLL
std::shared_ptr<Buffer> getStreamData(qpdf_stream_decode_level_e level = qpdf_dl_generalized);
// Returns unfiltered (raw) stream data.
QPDF_DLL
std::shared_ptr<Buffer> getRawStreamData();
// Write stream data through the given pipeline. A null pipeline value may be used if all you
// want to do is determine whether a stream is filterable and would be filtered based on the
// provided flags. If flags is 0, write raw stream data and return false. Otherwise, the flags
// alter the behavior in the following way:
//
// encode_flags:
//
// qpdf_sf_compress -- compress data with /FlateDecode if no other compression filters are
// applied.
//
// qpdf_sf_normalize -- tokenize as content stream and normalize tokens
//
// decode_level:
//
// qpdf_dl_none -- do not decode any streams.
//
// qpdf_dl_generalized -- decode supported general-purpose filters. This includes
// /ASCIIHexDecode, /ASCII85Decode, /LZWDecode, and /FlateDecode.
//
// qpdf_dl_specialized -- in addition to generalized filters, also decode supported non-lossy
// specialized filters. This includes /RunLengthDecode.
//
// qpdf_dl_all -- in addition to generalized and non-lossy specialized filters, decode supported
// lossy filters. This includes /DCTDecode.
//
// If, based on the flags and the filters and decode parameters, we determine that we know how
// to apply all requested filters, do so and return true if we are successful.
//
// The exact meaning of the return value differs the different versions of this function, but
// for any version, the meaning has been the same. For the main version, added in qpdf 10, the
// return value indicates whether the overall operation succeeded. The filter parameter, if
// specified, will be set to whether or not filtering was attempted. If filtering was not
// requested, this value will be false even if the overall operation succeeded.
//
// If filtering is requested but this method returns false, it means there was some error in the
// filtering, in which case the resulting data is likely partially filtered and/or incomplete
// and may not be consistent with the configured filters. QPDFWriter handles this by attempting
// to get the stream data without filtering, but callers should consider a false return value
// when decode_level is not qpdf_dl_none to be a potential loss of data. If you intend to retry
// in that case, pass true as the value of will_retry. This changes the warning issued by the
// library to indicate that the operation will be retried without filtering to avoid data loss.
// Return value is overall success, even if filtering is not requested.
QPDF_DLL
bool pipeStreamData(
Pipeline*,
bool* filtering_attempted,
int encode_flags,
qpdf_stream_decode_level_e decode_level,
bool suppress_warnings = false,
bool will_retry = false);
// Legacy version. Return value is whether filtering was attempted. There is no way to determine
// success if filtering was not attempted.
QPDF_DLL
bool pipeStreamData(
Pipeline*,
int encode_flags,
qpdf_stream_decode_level_e decode_level,
bool suppress_warnings = false,
bool will_retry = false);
// Legacy pipeStreamData. This maps to the the flags-based pipeStreamData as follows:
// filter = false -> encode_flags = 0
// filter = true -> decode_level = qpdf_dl_generalized
// normalize = true -> encode_flags |= qpdf_sf_normalize
// compress = true -> encode_flags |= qpdf_sf_compress
// Return value is whether filtering was attempted.
QPDF_DLL
bool pipeStreamData(Pipeline*, bool filter, bool normalize, bool compress);
// Replace a stream's dictionary. The new dictionary must be consistent with the stream's data.
// This is most appropriately used when creating streams from scratch that will use a stream
// data provider and therefore start with an empty dictionary. It may be more convenient in
// this case than calling getDict and modifying it for each key. The pdf-create example does
// this.
QPDF_DLL
void replaceDict(QPDFObjectHandle const&);
// REPLACING STREAM DATA
// Note about all replaceStreamData methods: whatever values are passed as filter and
// decode_parms will overwrite /Filter and /DecodeParms in the stream. Passing a null object
// (QPDFObjectHandle::newNull()) will remove those values from the stream dictionary. From qpdf
// 11, passing an *uninitialized* QPDFObjectHandle (QPDFObjectHandle()) will leave any existing
// values untouched.
// Replace this stream's stream data with the given data buffer. The stream's /Length key is
// replaced with the length of the data buffer. The stream is interpreted as if the data read
// from the file, after any decryption filters have been applied, is as presented.
QPDF_DLL
void replaceStreamData(
std::shared_ptr<Buffer> data,
QPDFObjectHandle const& filter,
QPDFObjectHandle const& decode_parms);
// Replace the stream's stream data with the given string. This method will create a copy of the
// data rather than using the user-provided buffer as in the std::shared_ptr<Buffer> version of
// replaceStreamData.
QPDF_DLL
void replaceStreamData(
std::string const& data,
QPDFObjectHandle const& filter,
QPDFObjectHandle const& decode_parms);
// As above, replace this stream's stream data. Instead of directly providing a buffer with the
// stream data, call the given provider's provideStreamData method. See comments on the
// StreamDataProvider class (defined above) for details on the method. The data must be
// consistent with filter and decode_parms as provided. Although it is more complex to use this
// form of replaceStreamData than the one that takes a buffer, it makes it possible to avoid
// allocating memory for the stream data. Example programs are provided that use both forms of
// replaceStreamData.
// Note about stream length: for any given stream, the provider must provide the same amount of
// data each time it is called. This is critical for making linearization work properly.
// Versions of qpdf before 3.0.0 required a length to be specified here. Starting with
// version 3.0.0, this is no longer necessary (or permitted). The first time the stream data
// provider is invoked for a given stream, the actual length is stored. Subsequent times, it is
// enforced that the length be the same as the first time.
// If you have gotten a compile error here while building code that worked with older versions
// of qpdf, just omit the length parameter. You can also simplify your code by not having to
// compute the length in advance.
QPDF_DLL
void replaceStreamData(
std::shared_ptr<StreamDataProvider> provider,
QPDFObjectHandle const& filter,
QPDFObjectHandle const& decode_parms);
// Starting in qpdf 10.2, you can use C++-11 function objects instead of StreamDataProvider.
// The provider should write the stream data to the pipeline. For a one-liner to replace stream
// data with the contents of a file, pass QUtil::file_provider(filename) as provider.
QPDF_DLL
void replaceStreamData(
std::function<void(Pipeline*)> provider,
QPDFObjectHandle const& filter,
QPDFObjectHandle const& decode_parms);
// The provider should write the stream data to the pipeline, returning true if it succeeded
// without errors.
QPDF_DLL
void replaceStreamData(
std::function<bool(Pipeline*, bool suppress_warnings, bool will_retry)> provider,
QPDFObjectHandle const& filter,
QPDFObjectHandle const& decode_parms);
// Access object ID and generation. For direct objects, return object ID 0.
// NOTE: Be careful about calling getObjectID() and getGeneration() directly as this can lead to
// the pattern of depending on object ID or generation without the other. In general, when
// keeping track of object IDs, it's better to use QPDFObjGen instead.
QPDF_DLL
QPDFObjGen getObjGen() const;
QPDF_DLL
inline int getObjectID() const;
QPDF_DLL
inline int getGeneration() const;
QPDF_DLL
std::string unparse();
QPDF_DLL
std::string unparseResolved();
// For strings only, force binary representation. Otherwise, same as unparse.
QPDF_DLL
std::string unparseBinary();
// Return encoded as JSON. The constant JSON::LATEST can be used to specify the latest available
// JSON version. The JSON is generated as follows:
// * Arrays, dictionaries, booleans, nulls, integers, and real numbers are represented by their
// native JSON types.
// * Names are encoded as strings representing the canonical representation (after parsing #xx)
// and preceded by a slash, just as unparse() returns. For example, the JSON for the
// PDF-syntax name /Text#2fPlain would be "/Text/Plain".
// * Indirect references are encoded as strings containing "obj gen R"
// * Strings
// * JSON v1: Strings are encoded as UTF-8 strings with unrepresentable binary characters
// encoded as \uHHHH. Characters in PDF Doc encoding that don't have bidirectional unicode
// mappings are not reversible. There is no way to tell the difference between a string that
// looks like a name or indirect object from an actual name or indirect object.
// * JSON v2:
// * Unicode strings and strings encoded with PDF Doc encoding that can be bidirectionally
// mapped to Unicode (which is all strings without undefined characters) are represented
// as "u:" followed by the UTF-8 encoded string. Example:
// "u:potato".
// * All other strings are represented as "b:" followed by a hexadecimal encoding of the
// string. Example: "b:0102cacb"
// * Streams
// * JSON v1: Only the stream's dictionary is encoded. There is no way to tell a stream from a
// dictionary other than context.
// * JSON v2: A stream is encoded as {"dict": {...}} with the value being the encoding of the
// stream's dictionary. Since "dict" does not otherwise represent anything, this is
// unambiguous. The getStreamJSON() call can be used to add encoding of the stream's data.
// * Object types that are only valid in content streams (inline image, operator) are serialized
// as "null". Attempting to serialize a "reserved" object is an error.
// If dereference_indirect is true and this is an indirect object, show the actual contents of
// the object. The effect of dereference_indirect applies only to this object. It is not
// recursive.
QPDF_DLL
JSON getJSON(int json_version, bool dereference_indirect = false);
// Write the object encoded as JSON to a pipeline. This is equivalent to, but more efficient
// than, calling getJSON(json_version, dereference_indirect).write(p, depth). See the
// documentation for getJSON and JSON::write for further detail.
QPDF_DLL
void
writeJSON(int json_version, Pipeline* p, bool dereference_indirect = false, size_t depth = 0);
// Deprecated version uses v1 for backward compatibility.
// ABI: remove for qpdf 12
[[deprecated("Use getJSON(int version)")]] QPDF_DLL JSON
getJSON(bool dereference_indirect = false);
// This method can be called on a stream to get a more extended JSON representation of the
// stream that includes the stream's data. The JSON object returned is always a dictionary whose
// "dict" key is an encoding of the stream's dictionary. The representation of the data is
// determined by the json_data field.
//
// The json_data field may have the value qpdf_sj_none, qpdf_sj_inline, or qpdf_sj_file.
//
// If json_data is qpdf_sj_none, stream data is not represented.
//
// If json_data is qpdf_sj_inline or qpdf_sj_file, then stream data is filtered or not based on
// the value of decode_level, which has the same meaning as with pipeStreamData.
//
// If json_data is qpdf_sj_inline, the base64-encoded stream data is included in the "data"
// field of the dictionary that is returned.
//
// If json_data is qpdf_sj_file, then the Pipeline ("p") and data_filename argument must be
// supplied. The value of data_filename is stored in the resulting json in the "datafile" key
// but is not otherwise use. The stream data itself (raw or filtered depending on decode level),
// is written to the pipeline via pipeStreamData().
//
// NOTE: When json_data is qpdf_sj_inline, the QPDF object from which the stream originates must
// remain valid until after the JSON object is written.
QPDF_DLL
JSON getStreamJSON(
int json_version,
qpdf_json_stream_data_e json_data,
qpdf_stream_decode_level_e decode_level,
Pipeline* p,
std::string const& data_filename);
// Legacy helper methods for commonly performed operations on pages. Newer code should use
// QPDFPageObjectHelper instead. The specification and behavior of these methods are the same as
// the identically named methods in that class, but newer functionality will be added there.
QPDF_DLL
std::map<std::string, QPDFObjectHandle> getPageImages();
QPDF_DLL
std::vector<QPDFObjectHandle> getPageContents();
QPDF_DLL
void addPageContents(QPDFObjectHandle contents, bool first);
QPDF_DLL
void rotatePage(int angle, bool relative);
QPDF_DLL
void coalesceContentStreams();
// End legacy page helpers
// Issue a warning about this object if possible. If the object has a description, a warning
// will be issued using the owning QPDF as context. Otherwise, a message will be written to the
// default logger's error stream, which is standard error if not overridden. Objects read
// normally from the file have descriptions. See comments on setObjectDescription for additional
// details.
QPDF_DLL
void warnIfPossible(std::string const& warning);
// Provide access to specific classes for recursive disconnected().
class DisconnectAccess
{
friend class QPDF_Dictionary;
friend class QPDF_Stream;
private:
static void
disconnect(QPDFObjectHandle o)
{
o.disconnect();
}
};
// Convenience routine: Throws if the assumption is violated. Your code will be better if you
// call one of the isType methods and handle the case of the type being wrong, but these can be
// convenient if you have already verified the type.
QPDF_DLL
void assertInitialized() const;
QPDF_DLL
void assertNull();
QPDF_DLL
void assertBool();
QPDF_DLL
void assertInteger();
QPDF_DLL
void assertReal();
QPDF_DLL
void assertName();
QPDF_DLL
void assertString();
QPDF_DLL
void assertOperator();
QPDF_DLL
void assertInlineImage();
QPDF_DLL
void assertArray();
QPDF_DLL
void assertDictionary();
QPDF_DLL
void assertStream();
QPDF_DLL
void assertReserved();
QPDF_DLL
void assertIndirect();
QPDF_DLL
void assertScalar();
QPDF_DLL
void assertNumber();
// The isPageObject method checks the /Type key of the object. This is not completely reliable
// as there are some otherwise valid files whose /Type is wrong for page objects. qpdf is
// slightly more accepting but may still return false here when treating the object as a page
// would work. Use this sparingly.
QPDF_DLL
bool isPageObject();
QPDF_DLL
bool isPagesObject();
QPDF_DLL
void assertPageObject();
QPDF_DLL
bool isFormXObject();
// Indicate if this is an image. If exclude_imagemask is true, don't count image masks as
// images.
QPDF_DLL
bool isImage(bool exclude_imagemask = true);
// The following methods do not form part of the public API and are for internal use only.
QPDFObjectHandle(std::shared_ptr<QPDFObject> const& obj) :
obj(obj)
{
}
std::shared_ptr<QPDFObject>
getObj()
{
return obj;
}
std::shared_ptr<QPDFObject>
getObj() const
{
return obj;
}
QPDFObject*
getObjectPtr()
{
return obj.get();
}
QPDFObject* const
getObjectPtr() const
{
return obj.get();
}
void writeJSON(int json_version, JSON::Writer& p, bool dereference_indirect = false);
private:
QPDF_Array* asArray();
QPDF_Bool* asBool();
QPDF_Dictionary* asDictionary();
QPDF_InlineImage* asInlineImage();
QPDF_Integer* asInteger();
QPDF_Name* asName();
QPDF_Null* asNull();
QPDF_Operator* asOperator();
QPDF_Real* asReal();
QPDF_Reserved* asReserved();
QPDF_Stream* asStream();
QPDF_Stream* asStreamWithAssert();
QPDF_String* asString();
void typeWarning(char const* expected_type, std::string const& warning);
void objectWarning(std::string const& warning);
void assertType(char const* type_name, bool istype);
inline bool dereference();
void makeDirect(QPDFObjGen::set& visited, bool stop_at_streams);
void disconnect();
void setParsedOffset(qpdf_offset_t offset);
void parseContentStream_internal(std::string const& description, ParserCallbacks* callbacks);
static void parseContentStream_data(
std::shared_ptr<Buffer>,
std::string const& description,
ParserCallbacks* callbacks,
QPDF* context);
std::vector<QPDFObjectHandle>
arrayOrStreamToStreamArray(std::string const& description, std::string& all_description);
static void warn(QPDF*, QPDFExc const&);
void checkOwnership(QPDFObjectHandle const&) const;
// Moving members of QPDFObjectHandle into a smart pointer incurs a substantial performance
// penalty since QPDFObjectHandle objects are copied around so frequently.
std::shared_ptr<QPDFObject> obj;
};
#ifndef QPDF_NO_QPDF_STRING
// This is short for QPDFObjectHandle::parse, so you can do
// auto oh = "<< /Key (value) >>"_qpdf;
// If this is causing problems in your code, define QPDF_NO_QPDF_STRING to prevent the declaration
// from being here.
/* clang-format off */
// Disable formatting for this declaration: emacs font-lock in cc-mode (as of 28.1) treats the rest
// of the file as a string if clang-format removes the space after "operator", and as of
// clang-format 15, there's no way to prevent it from doing so.
QPDF_DLL
QPDFObjectHandle operator ""_qpdf(char const* v, size_t len);
/* clang-format on */
#endif // QPDF_NO_QPDF_STRING
class QPDFObjectHandle::QPDFDictItems
{
// This class allows C++-style iteration, including range-for iteration, around dictionaries.
// You can write
// for (auto iter: QPDFDictItems(dictionary_obj))
// {
// // iter.first is a string
// // iter.second is a QPDFObjectHandle
// }
// See examples/pdf-name-number-tree.cc for a demonstration of using this API.
public:
QPDF_DLL
QPDFDictItems(QPDFObjectHandle const& oh);
class iterator
{
friend class QPDFDictItems;
public:
typedef std::pair<std::string, QPDFObjectHandle> T;
using iterator_category = std::bidirectional_iterator_tag;
using value_type = T;
using difference_type = long;
using pointer = T*;
using reference = T&;
QPDF_DLL
virtual ~iterator() = default;
QPDF_DLL
iterator& operator++();
QPDF_DLL
iterator
operator++(int)
{
iterator t = *this;
++(*this);
return t;
}
QPDF_DLL
iterator& operator--();
QPDF_DLL
iterator
operator--(int)
{
iterator t = *this;
--(*this);
return t;
}
QPDF_DLL
reference operator*();
QPDF_DLL
pointer operator->();
QPDF_DLL
bool operator==(iterator const& other) const;
QPDF_DLL
bool
operator!=(iterator const& other) const
{
return !operator==(other);
}
private:
iterator(QPDFObjectHandle& oh, bool for_begin);
void updateIValue();
class Members
{
friend class QPDFDictItems::iterator;
public:
QPDF_DLL
~Members() = default;
private:
Members(QPDFObjectHandle& oh, bool for_begin);
Members() = delete;
Members(Members const&) = delete;
QPDFObjectHandle& oh;
std::set<std::string> keys;
std::set<std::string>::iterator iter;
bool is_end;
};
std::shared_ptr<Members> m;
value_type ivalue;
};
QPDF_DLL
iterator begin();
QPDF_DLL
iterator end();
private:
QPDFObjectHandle oh;
};
class QPDFObjectHandle::QPDFArrayItems
{
// This class allows C++-style iteration, including range-for iteration, around arrays. You can
// write
// for (auto iter: QPDFArrayItems(array_obj))
// {
// // iter is a QPDFObjectHandle
// }
// See examples/pdf-name-number-tree.cc for a demonstration of using this API.
public:
QPDF_DLL
QPDFArrayItems(QPDFObjectHandle const& oh);
class iterator
{
friend class QPDFArrayItems;
public:
typedef QPDFObjectHandle T;
using iterator_category = std::bidirectional_iterator_tag;
using value_type = T;
using difference_type = long;
using pointer = T*;
using reference = T&;
QPDF_DLL
virtual ~iterator() = default;
QPDF_DLL
iterator& operator++();
QPDF_DLL
iterator
operator++(int)
{
iterator t = *this;
++(*this);
return t;
}
QPDF_DLL
iterator& operator--();
QPDF_DLL
iterator
operator--(int)
{
iterator t = *this;
--(*this);
return t;
}
QPDF_DLL
reference operator*();
QPDF_DLL
pointer operator->();
QPDF_DLL
bool operator==(iterator const& other) const;
QPDF_DLL
bool
operator!=(iterator const& other) const
{
return !operator==(other);
}
private:
iterator(QPDFObjectHandle& oh, bool for_begin);
void updateIValue();
class Members
{
friend class QPDFArrayItems::iterator;
public:
QPDF_DLL
~Members() = default;
private:
Members(QPDFObjectHandle& oh, bool for_begin);
Members() = delete;
Members(Members const&) = delete;
QPDFObjectHandle& oh;
int item_number;
bool is_end;
};
std::shared_ptr<Members> m;
value_type ivalue;
};
QPDF_DLL
iterator begin();
QPDF_DLL
iterator end();
private:
QPDFObjectHandle oh;
};
inline int
QPDFObjectHandle::getObjectID() const
{
return getObjGen().getObj();
}
inline int
QPDFObjectHandle::getGeneration() const
{
return getObjGen().getGen();
}
inline bool
QPDFObjectHandle::isIndirect() const
{
return (obj != nullptr) && (getObjectID() != 0);
}
inline bool
QPDFObjectHandle::isInitialized() const
{
return obj != nullptr;
}
#endif // QPDFOBJECTHANDLE_HH
