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mirror of https://github.com/qpdf/qpdf.git synced 2024-12-22 02:49:00 +00:00

Refactor resolving of objects

This commit is contained in:
m-holger 2024-03-10 15:34:58 +00:00
parent ce5b864c53
commit 9641626cae
9 changed files with 111 additions and 118 deletions

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@ -792,12 +792,13 @@ class QPDF
class Resolver
{
friend class QPDFObject;
friend class QPDF_Unresolved;
private:
static void
resolve(QPDF* qpdf, QPDFObjGen const& og)
static QPDFObject*
resolved(QPDF* qpdf, QPDFObjGen og)
{
qpdf->resolve(og);
return qpdf->resolve(og);
}
};
@ -1056,7 +1057,7 @@ class QPDF
QPDFObjGen exp_og,
QPDFObjGen& og,
bool skip_cache_if_in_xref);
void resolve(QPDFObjGen og);
QPDFObject* resolve(QPDFObjGen og);
void resolveObjectsInStream(int obj_stream_number);
void stopOnError(std::string const& message);
QPDFObjectHandle reserveObjectIfNotExists(QPDFObjGen const& og);

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@ -1363,24 +1363,23 @@ class QPDFObjectHandle
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_Array* asArray() const;
QPDF_Bool* asBool() const;
QPDF_Dictionary* asDictionary() const;
QPDF_InlineImage* asInlineImage() const;
QPDF_Integer* asInteger() const;
QPDF_Name* asName() const;
QPDF_Null* asNull() const;
QPDF_Operator* asOperator() const;
QPDF_Real* asReal() const;
QPDF_Reserved* asReserved() const;
QPDF_Stream* asStream() const;
QPDF_Stream* asStreamWithAssert();
QPDF_String* asString();
QPDF_String* asString() const;
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);

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@ -1728,11 +1728,11 @@ QPDF::readObjectAtOffset(
return oh;
}
void
QPDFObject*
QPDF::resolve(QPDFObjGen og)
{
if (!isUnresolved(og)) {
return;
return m->obj_cache[og].object.get();
}
if (m->resolving.count(og)) {
@ -1741,7 +1741,7 @@ QPDF::resolve(QPDFObjGen og)
QTC::TC("qpdf", "QPDF recursion loop in resolve");
warn(damagedPDF("", "loop detected resolving object " + og.unparse(' ')));
updateCache(og, QPDF_Null::create(), -1, -1);
return;
return m->obj_cache[og].object.get();
}
ResolveRecorder rr(this, og);
@ -1782,6 +1782,7 @@ QPDF::resolve(QPDFObjGen og)
auto result(m->obj_cache[og].object);
result->setDefaultDescription(this, og);
return result.get();
}
void

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@ -3,13 +3,6 @@
#include <qpdf/QPDF.hh>
#include <qpdf/QPDF_Destroyed.hh>
void
QPDFObject::doResolve()
{
auto og = value->og;
QPDF::Resolver::resolve(value->qpdf, og);
}
void
QPDFObject::destroy()
{

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@ -240,79 +240,79 @@ QPDFObjectHandle::disconnect()
qpdf_object_type_e
QPDFObjectHandle::getTypeCode()
{
return dereference() ? this->obj->getTypeCode() : ::ot_uninitialized;
return obj ? obj->getResolvedTypeCode() : ::ot_uninitialized;
}
char const*
QPDFObjectHandle::getTypeName()
{
return dereference() ? this->obj->getTypeName() : "uninitialized";
return obj ? obj->getTypeName() : "uninitialized";
}
QPDF_Array*
QPDFObjectHandle::asArray()
QPDFObjectHandle::asArray() const
{
return dereference() ? obj->as<QPDF_Array>() : nullptr;
return obj ? obj->as<QPDF_Array>() : nullptr;
}
QPDF_Bool*
QPDFObjectHandle::asBool()
QPDFObjectHandle::asBool() const
{
return dereference() ? obj->as<QPDF_Bool>() : nullptr;
return obj ? obj->as<QPDF_Bool>() : nullptr;
}
QPDF_Dictionary*
QPDFObjectHandle::asDictionary()
QPDFObjectHandle::asDictionary() const
{
return dereference() ? obj->as<QPDF_Dictionary>() : nullptr;
return obj ? obj->as<QPDF_Dictionary>() : nullptr;
}
QPDF_InlineImage*
QPDFObjectHandle::asInlineImage()
QPDFObjectHandle::asInlineImage() const
{
return dereference() ? obj->as<QPDF_InlineImage>() : nullptr;
return obj ? obj->as<QPDF_InlineImage>() : nullptr;
}
QPDF_Integer*
QPDFObjectHandle::asInteger()
QPDFObjectHandle::asInteger() const
{
return dereference() ? obj->as<QPDF_Integer>() : nullptr;
return obj ? obj->as<QPDF_Integer>() : nullptr;
}
QPDF_Name*
QPDFObjectHandle::asName()
QPDFObjectHandle::asName() const
{
return dereference() ? obj->as<QPDF_Name>() : nullptr;
return obj ? obj->as<QPDF_Name>() : nullptr;
}
QPDF_Null*
QPDFObjectHandle::asNull()
QPDFObjectHandle::asNull() const
{
return dereference() ? obj->as<QPDF_Null>() : nullptr;
return obj ? obj->as<QPDF_Null>() : nullptr;
}
QPDF_Operator*
QPDFObjectHandle::asOperator()
QPDFObjectHandle::asOperator() const
{
return dereference() ? obj->as<QPDF_Operator>() : nullptr;
return obj ? obj->as<QPDF_Operator>() : nullptr;
}
QPDF_Real*
QPDFObjectHandle::asReal()
QPDFObjectHandle::asReal() const
{
return dereference() ? obj->as<QPDF_Real>() : nullptr;
return obj ? obj->as<QPDF_Real>() : nullptr;
}
QPDF_Reserved*
QPDFObjectHandle::asReserved()
QPDFObjectHandle::asReserved() const
{
return dereference() ? obj->as<QPDF_Reserved>() : nullptr;
return obj ? obj->as<QPDF_Reserved>() : nullptr;
}
QPDF_Stream*
QPDFObjectHandle::asStream()
QPDFObjectHandle::asStream() const
{
return dereference() ? obj->as<QPDF_Stream>() : nullptr;
return obj ? obj->as<QPDF_Stream>() : nullptr;
}
QPDF_Stream*
@ -324,21 +324,21 @@ QPDFObjectHandle::asStreamWithAssert()
}
QPDF_String*
QPDFObjectHandle::asString()
QPDFObjectHandle::asString() const
{
return dereference() ? obj->as<QPDF_String>() : nullptr;
return obj ? obj->as<QPDF_String>() : nullptr;
}
bool
QPDFObjectHandle::isDestroyed()
{
return dereference() && (obj->getTypeCode() == ::ot_destroyed);
return obj && obj->getResolvedTypeCode() == ::ot_destroyed;
}
bool
QPDFObjectHandle::isBool()
{
return dereference() && (obj->getTypeCode() == ::ot_boolean);
return obj && obj->getResolvedTypeCode() == ::ot_boolean;
}
bool
@ -346,25 +346,25 @@ QPDFObjectHandle::isDirectNull() const
{
// Don't call dereference() -- this is a const method, and we know
// objid == 0, so there's nothing to resolve.
return (isInitialized() && (getObjectID() == 0) && (obj->getTypeCode() == ::ot_null));
return (obj && getObjectID() == 0 && obj->getTypeCode() == ::ot_null);
}
bool
QPDFObjectHandle::isNull()
{
return dereference() && (obj->getTypeCode() == ::ot_null);
return obj && obj->getResolvedTypeCode() == ::ot_null;
}
bool
QPDFObjectHandle::isInteger()
{
return dereference() && (obj->getTypeCode() == ::ot_integer);
return obj && obj->getResolvedTypeCode() == ::ot_integer;
}
bool
QPDFObjectHandle::isReal()
{
return dereference() && (obj->getTypeCode() == ::ot_real);
return obj && obj->getResolvedTypeCode() == ::ot_real;
}
bool
@ -401,49 +401,49 @@ QPDFObjectHandle::getValueAsNumber(double& value)
bool
QPDFObjectHandle::isName()
{
return dereference() && (obj->getTypeCode() == ::ot_name);
return obj && obj->getResolvedTypeCode() == ::ot_name;
}
bool
QPDFObjectHandle::isString()
{
return dereference() && (obj->getTypeCode() == ::ot_string);
return obj && obj->getResolvedTypeCode() == ::ot_string;
}
bool
QPDFObjectHandle::isOperator()
{
return dereference() && (obj->getTypeCode() == ::ot_operator);
return obj && obj->getResolvedTypeCode() == ::ot_operator;
}
bool
QPDFObjectHandle::isInlineImage()
{
return dereference() && (obj->getTypeCode() == ::ot_inlineimage);
return obj && obj->getResolvedTypeCode() == ::ot_inlineimage;
}
bool
QPDFObjectHandle::isArray()
{
return dereference() && (obj->getTypeCode() == ::ot_array);
return obj && obj->getResolvedTypeCode() == ::ot_array;
}
bool
QPDFObjectHandle::isDictionary()
{
return dereference() && (obj->getTypeCode() == ::ot_dictionary);
return obj && obj->getResolvedTypeCode() == ::ot_dictionary;
}
bool
QPDFObjectHandle::isStream()
{
return dereference() && (obj->getTypeCode() == ::ot_stream);
return obj && obj->getResolvedTypeCode() == ::ot_stream;
}
bool
QPDFObjectHandle::isReserved()
{
return dereference() && (obj->getTypeCode() == ::ot_reserved);
return obj && obj->getResolvedTypeCode() == ::ot_reserved;
}
bool
@ -1586,7 +1586,7 @@ QPDFObjectHandle::unparse()
std::string
QPDFObjectHandle::unparseResolved()
{
if (!dereference()) {
if (!obj) {
throw std::logic_error("attempted to dereference an uninitialized QPDFObjectHandle");
}
return obj->unparse();
@ -1615,7 +1615,7 @@ QPDFObjectHandle::getJSON(int json_version, bool dereference_indirect)
{
if ((!dereference_indirect) && isIndirect()) {
return JSON::makeString(unparse());
} else if (!dereference()) {
} else if (!obj) {
throw std::logic_error("attempted to dereference an uninitialized QPDFObjectHandle");
} else {
Pl_Buffer p{"json"};
@ -1631,7 +1631,7 @@ QPDFObjectHandle::writeJSON(int json_version, JSON::Writer& p, bool dereference_
{
if (!dereference_indirect && isIndirect()) {
p << "\"" << getObjGen().unparse(' ') << " R\"";
} else if (!dereference()) {
} else if (!obj) {
throw std::logic_error("attempted to dereference an uninitialized QPDFObjectHandle");
} else {
obj->writeJSON(json_version, p);
@ -1874,11 +1874,7 @@ QPDFObjectHandle::parse(
qpdf_offset_t
QPDFObjectHandle::getParsedOffset()
{
if (dereference()) {
return this->obj->getParsedOffset();
} else {
return -1;
}
return obj ? obj->getParsedOffset() : -1;
}
QPDFObjectHandle
@ -2055,9 +2051,7 @@ QPDFObjectHandle::newReserved(QPDF* qpdf)
void
QPDFObjectHandle::setObjectDescription(QPDF* owning_qpdf, std::string const& object_description)
{
// This is called during parsing on newly created direct objects, so we can't call dereference()
// here.
if (isInitialized() && obj.get()) {
if (obj) {
auto descr = std::make_shared<QPDFValue::Description>(object_description);
obj->setDescription(owning_qpdf, descr);
}
@ -2066,13 +2060,13 @@ QPDFObjectHandle::setObjectDescription(QPDF* owning_qpdf, std::string const& obj
bool
QPDFObjectHandle::hasObjectDescription()
{
return dereference() && obj.get() && obj->hasDescription();
return obj && obj->hasDescription();
}
QPDFObjectHandle
QPDFObjectHandle::shallowCopy()
{
if (!dereference()) {
if (!obj) {
throw std::logic_error("operation attempted on uninitialized QPDFObjectHandle");
}
return {obj->copy()};
@ -2081,7 +2075,7 @@ QPDFObjectHandle::shallowCopy()
QPDFObjectHandle
QPDFObjectHandle::unsafeShallowCopy()
{
if (!dereference()) {
if (!obj) {
throw std::logic_error("operation attempted on uninitialized QPDFObjectHandle");
}
return {obj->copy(true)};
@ -2172,10 +2166,10 @@ QPDFObjectHandle::typeWarning(char const* expected_type, std::string const& warn
std::string description;
// Type checks above guarantee that the object has been dereferenced. Nevertheless, dereference
// throws exceptions in the test suite
if (!dereference()) {
if (!obj) {
throw std::logic_error("attempted to dereference an uninitialized QPDFObjectHandle");
}
this->obj->getDescription(context, description);
obj->getDescription(context, description);
// Null context handled by warn
warn(
context,
@ -2193,7 +2187,7 @@ QPDFObjectHandle::warnIfPossible(std::string const& warning)
{
QPDF* context = nullptr;
std::string description;
if (dereference() && obj->getDescription(context, description)) {
if (obj && obj->getDescription(context, description)) {
warn(context, QPDFExc(qpdf_e_damaged_pdf, "", description, 0, warning));
} else {
*QPDFLogger::defaultLogger()->getError() << warning << "\n";
@ -2205,8 +2199,8 @@ QPDFObjectHandle::objectWarning(std::string const& warning)
{
QPDF* context = nullptr;
std::string description;
// Type checks above guarantee that the object has been dereferenced.
this->obj->getDescription(context, description);
// Type checks above guarantee that the object is initialized.
obj->getDescription(context, description);
// Null context handled by warn
warn(context, QPDFExc(qpdf_e_object, "", description, 0, warning));
}
@ -2372,16 +2366,6 @@ QPDFObjectHandle::assertPageObject()
}
}
inline bool
QPDFObjectHandle::dereference()
{
if (!isInitialized()) {
return false;
}
this->obj->resolve();
return true;
}
void
QPDFObjectHandle::warn(QPDF* qpdf, QPDFExc const& e)
{

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@ -130,8 +130,7 @@ QPDF_Array::unparse()
for (int j = next; j < key; ++j) {
result += "null ";
}
item.second->resolve();
auto og = item.second->getObjGen();
auto og = item.second->resolved_object()->getObjGen();
result += og.isIndirect() ? og.unparse(' ') + " R " : item.second->unparse() + " ";
next = ++key;
}
@ -140,8 +139,7 @@ QPDF_Array::unparse()
}
} else {
for (auto const& item: elements) {
item->resolve();
auto og = item->getObjGen();
auto og = item->resolved_object()->getObjGen();
result += og.isIndirect() ? og.unparse(' ') + " R " : item->unparse() + " ";
}
}

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@ -1,6 +1,7 @@
#include <qpdf/QPDF_Unresolved.hh>
#include <stdexcept>
#include <qpdf/QPDF.hh>
#include <qpdf/QPDFObject_private.hh>
QPDF_Unresolved::QPDF_Unresolved(QPDF* qpdf, QPDFObjGen const& og) :
QPDFValue(::ot_unresolved, "unresolved", qpdf, og)
@ -16,19 +17,23 @@ QPDF_Unresolved::create(QPDF* qpdf, QPDFObjGen const& og)
std::shared_ptr<QPDFObject>
QPDF_Unresolved::copy(bool shallow)
{
throw std::logic_error("attempted to shallow copy an unresolved QPDFObjectHandle");
return nullptr;
return QPDF::Resolver::resolved(qpdf, og)->copy(shallow);
}
std::string
QPDF_Unresolved::unparse()
{
throw std::logic_error("attempted to unparse an unresolved QPDFObjectHandle");
return "";
return QPDF::Resolver::resolved(qpdf, og)->unparse();
}
void
QPDF_Unresolved::writeJSON(int json_version, JSON::Writer& p)
{
throw std::logic_error("attempted to get JSON from an unresolved QPDFObjectHandle");
QPDF::Resolver::resolved(qpdf, og)->writeJSON(json_version, p);
}
std::string
QPDF_Unresolved::getStringValue() const
{
return QPDF::Resolver::resolved(qpdf, og)->getStringValue();
}

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@ -5,8 +5,8 @@
// include/qpdf/QPDFObject.hh. See comments there for an explanation.
#include <qpdf/Constants.h>
#include <qpdf/DLL.h>
#include <qpdf/JSON.hh>
#include <qpdf/QPDF.hh>
#include <qpdf/QPDFValue.hh>
#include <qpdf/Types.h>
@ -43,18 +43,26 @@ class QPDFObject
{
return value->getStringValue();
}
// Return a unique type code for the resolved object
qpdf_object_type_e
getResolvedTypeCode() const
{
auto tc = value->type_code;
return tc == ::ot_unresolved
? QPDF::Resolver::resolved(value->qpdf, value->og)->value->type_code
: tc;
}
// Return a unique type code for the object
qpdf_object_type_e
getTypeCode() const
getTypeCode() const noexcept
{
return value->type_code;
}
// Return a string literal that describes the type, useful for debugging and testing
char const*
getTypeName() const
{
return value->type_name;
return resolved_object()->value->type_name;
}
QPDF*
@ -157,20 +165,23 @@ class QPDFObject
{
return value->type_code == ::ot_unresolved;
}
void
resolve()
const QPDFObject*
resolved_object() const
{
if (isUnresolved()) {
doResolve();
}
return isUnresolved() ? QPDF::Resolver::resolved(value->qpdf, value->og) : this;
}
void doResolve();
template <typename T>
T*
as()
as() const
{
return dynamic_cast<T*>(value.get());
if (auto result = dynamic_cast<T*>(value.get())) {
return result;
} else {
return isUnresolved()
? dynamic_cast<T*>(QPDF::Resolver::resolved(value->qpdf, value->og)->value.get())
: nullptr;
}
}
private:

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@ -11,6 +11,7 @@ class QPDF_Unresolved: public QPDFValue
std::shared_ptr<QPDFObject> copy(bool shallow = false) override;
std::string unparse() override;
void writeJSON(int json_version, JSON::Writer& p) override;
std::string getStringValue() const override;
private:
QPDF_Unresolved(QPDF* qpdf, QPDFObjGen const& og);