This abstract base class provides the common functionality of an IFD directory entry and defines an extended interface for derived concrete entries, which allows access to the attributes of the entry. More...

#include <tiffcomposite_int.hpp>

Inheritance diagram for Exiv2::Internal::TiffEntryBase:

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Public Member Functions
Creators
constexpr	TiffEntryBase (uint16_t tag, IfdId group, TiffType tiffType=ttUndefined)
	Default constructor.

	~TiffEntryBase () override=default
	Virtual destructor.

NOT implemented
TiffEntryBase &	operator= (const TiffEntryBase &)=delete
	Assignment operator.

Manipulators
void	encode (TiffEncoder &encoder, const Exifdatum *datum)
	Encode a TIFF component from the metadatum provided and information from the encoder as needed.

void	setOffset (size_t offset)
	Set the offset.

void	setData (byte *pData, size_t size, std::shared_ptr< DataBuf > storage)
	Set pointer and size of the entry's data (not taking ownership of the data).

void	setData (std::shared_ptr< DataBuf > buf)
	Set the entry's data buffer. A shared_ptr is used to manage the DataBuf because TiffEntryBase has a clone method so it is possible (in theory) for the DataBuf to have multiple owners.

void	updateValue (Value::UniquePtr value, ByteOrder byteOrder)
	Update the value. Takes ownership of the pointer passed in.

void	setValue (Value::UniquePtr value)
	Set tag value. Takes ownership of the pointer passed in.

Accessors
TiffType	tiffType () const
	Return the TIFF type.

size_t	offset () const
	Return the offset to the data area relative to the base for the component (usually the start of the TIFF header)

int	idx () const override
	Return the unique id of the entry in the image.

const byte *	pData () const
	Return a pointer to the binary representation of the value of this component.

const Value *	pValue () const
	Return a const pointer to the converted value of this component.

Public Member Functions inherited from Exiv2::Internal::TiffComponent
constexpr	TiffComponent (uint16_t tag, IfdId group)
	Constructor.

virtual	~TiffComponent ()=default
	Virtual destructor.

	TiffComponent (const TiffComponent &)=default

TiffComponent &	operator= (const TiffComponent &)=default

TiffComponent *	addPath (uint16_t tag, TiffPath &tiffPath, TiffComponent *pRoot, UniquePtr object=nullptr)
	Add a TIFF entry tag to the component. Components on the path to the entry are added if they don't exist yet.

TiffComponent *	addChild (UniquePtr tiffComponent)
	Add a child to the component. Default is to do nothing.

TiffComponent *	addNext (UniquePtr tiffComponent)
	Add a "next" component to the component. Default is to do nothing.

void	accept (TiffVisitor &visitor)
	Interface to accept visitors (Visitor pattern). Visitors can perform operations on all components of the composite.

void	setStart (const byte *pStart)
	Set a pointer to the start of the binary representation of the component in a memory buffer. The buffer must be allocated and freed outside of this class.

size_t	write (IoWrapper &ioWrapper, ByteOrder byteOrder, size_t offset, size_t valueIdx, size_t dataIdx, size_t &imageIdx)
	Write a TiffComponent to a binary image.

uint16_t	tag () const
	Return the tag of this entry.

IfdId	group () const
	Return the group id of this component.

byte *	start () const
	Return a pointer to the start of the binary representation of the component.

UniquePtr	clone () const
	Return an auto-pointer to a copy of itself (deep copy, but without any children). The caller owns this copy and the auto-pointer ensures that it will be deleted.

size_t	writeData (IoWrapper &ioWrapper, ByteOrder byteOrder, size_t offset, size_t dataIdx, size_t &imageIdx) const
	Write the IFD data of this component to a binary image. Return the number of bytes written. Components derived from TiffEntryBase implement this method if needed.

size_t	writeImage (IoWrapper &ioWrapper, ByteOrder byteOrder) const
	Write the image data of this component to a binary image. Return the number of bytes written. TIFF components implement this method if needed.

size_t	size () const
	Return the size in bytes of the IFD value of this component when written to a binary image.

size_t	count () const
	Return the number of components in this component.

size_t	sizeData () const
	Return the size in bytes of the IFD data of this component when written to a binary image. This is a support function for write(). Components derived from TiffEntryBase implement this method corresponding to their implementation of writeData().

size_t	sizeImage () const
	Return the size in bytes of the image data of this component when written to a binary image. This is a support function for write(). TIFF components implement this method corresponding to their implementation of writeImage().

Protected Member Functions
Protected Creators
	TiffEntryBase (const TiffEntryBase &rhs)
	Copy constructor (used to implement clone()).

Protected Manipulators
virtual void	doEncode (TiffEncoder &encoder, const Exifdatum *datum)=0
	Implements encode().

void	setCount (size_t count)
	Set the number of components in this entry.

void	setIdx (int idx)
	Set the unique id of the entry in the image.

size_t	doWrite (IoWrapper &ioWrapper, ByteOrder byteOrder, size_t offset, size_t valueIdx, size_t dataIdx, size_t &imageIdx) override
	Implements write(). Write the value of a standard TIFF entry to the ioWrapper, return the number of bytes written. Only the ioWrapper and byteOrder arguments are used.

Protected Member Functions inherited from Exiv2::Internal::TiffComponent
virtual TiffComponent *	doAddPath (uint16_t tag, TiffPath &tiffPath, TiffComponent *pRoot, TiffComponent::UniquePtr object)
	Implements addPath(). The default implementation does nothing.

virtual TiffComponent *	doAddChild (UniquePtr tiffComponent)
	Implements addChild(). The default implementation does nothing.

virtual TiffComponent *	doAddNext (UniquePtr tiffComponent)
	Implements addNext(). The default implementation does nothing.

virtual void	doAccept (TiffVisitor &visitor)=0
	Implements accept().

virtual TiffComponent *	doClone () const =0
	Internal virtual copy constructor, implements clone().

Friends
class	TiffReader

class	TiffEncoder

Protected Accessors
size_t	doCount () const override
	Implements count().

size_t	doWriteData (IoWrapper &ioWrapper, ByteOrder byteOrder, size_t offset, size_t dataIdx, size_t &imageIdx) const override
	Implements writeData(). Standard TIFF entries have no data: write nothing and return 0.

size_t	doWriteImage (IoWrapper &ioWrapper, ByteOrder byteOrder) const override
	Implements writeImage(). Standard TIFF entries have no image data: write nothing and return 0.

size_t	doSize () const override
	Implements size(). Return the size of a standard TIFF entry.

size_t	doSizeData () const override
	Implements sizeData(). Return 0.

size_t	doSizeImage () const override
	Implements sizeImage(). Return 0.

std::shared_ptr< DataBuf >	storage () const
	Used (internally) to create another reference to the DataBuf reference by storage_.

static size_t	writeOffset (byte *buf, size_t offset, TiffType tiffType, ByteOrder byteOrder)
	Helper function to write an offset to a preallocated binary buffer.

Additional Inherited Members
Public Types inherited from Exiv2::Internal::TiffComponent
using	UniquePtr = std::unique_ptr< TiffComponent >
	TiffComponent auto_ptr type.

using	Components = std::vector< UniquePtr >
	Container type to hold all metadata.

Detailed Description

This abstract base class provides the common functionality of an IFD directory entry and defines an extended interface for derived concrete entries, which allows access to the attributes of the entry.

Member Function Documentation

◆ doCount()

size_t Exiv2::Internal::TiffEntryBase::doCount ( ) const

overrideprotectedvirtual

Implements count().

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffMnEntry.

Referenced by Exiv2::Internal::TiffMnEntry::doCount(), and Exiv2::Internal::TiffBinaryArray::doCount().

◆ doEncode()

virtual void Exiv2::Internal::TiffEntryBase::doEncode	(	TiffEncoder &	encoder,
		const Exifdatum *	datum
	)

protectedpure virtual

Implements encode().

Implemented in Exiv2::Internal::TiffEntry, Exiv2::Internal::TiffDataEntry, Exiv2::Internal::TiffImageEntry, Exiv2::Internal::TiffSizeEntry, Exiv2::Internal::TiffSubIfd, Exiv2::Internal::TiffMnEntry, Exiv2::Internal::TiffBinaryArray, and Exiv2::Internal::TiffBinaryElement.

Referenced by encode().

◆ doSize()

size_t Exiv2::Internal::TiffEntryBase::doSize ( ) const

overrideprotectedvirtual

Implements size(). Return the size of a standard TIFF entry.

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffImageEntry, Exiv2::Internal::TiffSubIfd, and Exiv2::Internal::TiffMnEntry.

Referenced by Exiv2::Internal::TiffBinaryArray::addElement(), Exiv2::Internal::TiffMnEntry::doSize(), Exiv2::Internal::TiffBinaryArray::doSize(), Exiv2::Internal::TiffBinaryArray::iniOrigDataBuf(), and Exiv2::Internal::TiffBinaryArray::initialize().

◆ doSizeData()

size_t Exiv2::Internal::TiffEntryBase::doSizeData ( ) const

overrideprotectedvirtual

Implements sizeData(). Return 0.

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffImageEntry, and Exiv2::Internal::TiffSubIfd.

◆ doSizeImage()

size_t Exiv2::Internal::TiffEntryBase::doSizeImage ( ) const

overrideprotectedvirtual

Implements sizeImage(). Return 0.

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffImageEntry, and Exiv2::Internal::TiffSubIfd.

◆ doWrite()

size_t Exiv2::Internal::TiffEntryBase::doWrite	(	IoWrapper &	ioWrapper,
		ByteOrder	byteOrder,
		size_t	offset,
		size_t	valueIdx,
		size_t	dataIdx,
		size_t &	imageIdx
	)

overrideprotectedvirtual

Implements write(). Write the value of a standard TIFF entry to the ioWrapper, return the number of bytes written. Only the ioWrapper and byteOrder arguments are used.

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffImageEntry, Exiv2::Internal::TiffSubIfd, and Exiv2::Internal::TiffMnEntry.

References Exiv2::DataBuf::c_data(), Exiv2::DataBuf::data(), and Exiv2::Internal::IoWrapper::write().

Referenced by Exiv2::Internal::TiffMnEntry::doWrite(), and Exiv2::Internal::TiffBinaryArray::doWrite().

◆ doWriteData()

size_t Exiv2::Internal::TiffEntryBase::doWriteData	(	IoWrapper &	ioWrapper,
		ByteOrder	byteOrder,
		size_t	offset,
		size_t	dataIdx,
		size_t &	imageIdx
	)		const

overrideprotectedvirtual

Implements writeData(). Standard TIFF entries have no data: write nothing and return 0.

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffImageEntry, and Exiv2::Internal::TiffSubIfd.

◆ doWriteImage()

size_t Exiv2::Internal::TiffEntryBase::doWriteImage	(	IoWrapper &	ioWrapper,
		ByteOrder	byteOrder
	)		const

overrideprotectedvirtual

Implements writeImage(). Standard TIFF entries have no image data: write nothing and return 0.

Implements Exiv2::Internal::TiffComponent.

Reimplemented in Exiv2::Internal::TiffImageEntry, and Exiv2::Internal::TiffSubIfd.

◆ encode()

void Exiv2::Internal::TiffEntryBase::encode	(	TiffEncoder &	encoder,
		const Exifdatum *	datum
	)

Encode a TIFF component from the metadatum provided and information from the encoder as needed.

Implemented as double-dispatch calls back to one of the specific encoding functions at the encoder.

References doEncode().

◆ idx()

int Exiv2::Internal::TiffEntryBase::idx ( ) const

overridevirtual

Return the unique id of the entry in the image.

Reimplemented from Exiv2::Internal::TiffComponent.

◆ setData()

void Exiv2::Internal::TiffEntryBase::setData	(	byte *	pData,
		size_t	size,
		std::shared_ptr< DataBuf >	storage
	)

Set pointer and size of the entry's data (not taking ownership of the data).

Parameters

storage Usually, pData is a pointer into a copy of the image file, which means that it points to memory which is guaranteed to live longer than this class. However, sometimes pData is pointer into a DataBuf that was allocated by another node in the component tree. If so, we need to make sure that the DataBuf doesn't get freed too early. We use a std::shared_ptr to hold a reference to the DataBuf to ensure that it will be kept alive. The storage parameter is assigned to the storage_ field. In the more common scenario where pData points to a copy of the image, rather than a DataBuf, then you should pass std::shared_ptr<DataBuf>(), which is essentially a nullptr.

References pData(), Exiv2::Internal::TiffComponent::size(), and storage().

Referenced by updateValue().

◆ setValue()

void Exiv2::Internal::TiffEntryBase::setValue ( Value::UniquePtr value )

Set tag value. Takes ownership of the pointer passed in.

Update type, count and the pointer to the value.

References Exiv2::Internal::toTiffType().

Referenced by updateValue().

◆ updateValue()

void Exiv2::Internal::TiffEntryBase::updateValue	(	Value::UniquePtr	value,
		ByteOrder	byteOrder
	)

Update the value. Takes ownership of the pointer passed in.

Update binary value data and call setValue().

References setData(), and setValue().

The documentation for this class was generated from the following files:

tiffcomposite_int.hpp
tiffcomposite_int.cpp

Public Member Functions

Protected Member Functions

Friends

Protected Accessors

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ doCount()

◆ doEncode()

◆ doSize()

◆ doSizeData()

◆ doSizeImage()

◆ doWrite()

◆ doWriteData()

◆ doWriteImage()

◆ encode()

◆ idx()

◆ setData()

◆ setValue()

◆ updateValue()