DataBlock Class Reference

A class that holds just a block of raw data. More...

#include <yateclass.h>

Inheritance diagram for DataBlock:

Public Member Functions
	DataBlock (unsigned int overAlloc=0)
	DataBlock (const DataBlock &value)
	DataBlock (const DataBlock &value, unsigned int overAlloc)
	DataBlock (void *value, unsigned int len, bool copyData=true, unsigned int overAlloc=0)
virtual	~DataBlock ()
virtual void *	getObject (const String &name) const
void *	data () const
unsigned char *	data (unsigned int offs, unsigned int len=1) const
int	at (unsigned int offs, int defvalue=-1) const
bool	null () const
unsigned int	length () const
unsigned int	overAlloc () const
void	overAlloc (unsigned int bytes)
void	clear (bool deleteData=true)
DataBlock &	assign (void *value, unsigned int len, bool copyData=true, unsigned int allocated=0)
void	append (void *value, unsigned int len)
void	append (const DataBlock &value)
void	append (const String &value)
void	insert (const DataBlock &value)
void	resize (unsigned int len)
void	truncate (unsigned int len)
void	cut (int len)
int	operator[] (signed int index) const
int	operator[] (unsigned int index) const
DataBlock &	operator= (const DataBlock &value)
DataBlock &	operator+= (const DataBlock &value)
DataBlock &	operator+= (const String &value)
bool	convert (const DataBlock &src, const String &sFormat, const String &dFormat, unsigned maxlen=0)
bool	unHexify (const char *data, unsigned int len, char sep)
bool	unHexify (const char *data, unsigned int len)
bool	unHexify (const String &data)
String	sqlEscape (char extraEsc) const
Public Member Functions inherited from GenObject
	GenObject ()
virtual	~GenObject ()
virtual bool	alive () const
virtual void	destruct ()
virtual const String &	toString () const
NamedCounter *	getObjCounter () const
NamedCounter *	setObjCounter (NamedCounter *counter)

Static Public Member Functions
static const DataBlock &	empty ()
Static Public Member Functions inherited from GenObject
static void *	getObject (const String &name, const GenObject *obj)
static bool	getObjCounting ()
static void	setObjCounting (bool enable)
static NamedCounter *	getObjCounter (const String &name, bool create=true)
static ObjList &	getObjCounters ()

Detailed Description

A class that holds just a block of raw data.

The DataBlock holds a data buffer with no specific formatting.

Constructor & Destructor Documentation

DataBlock

(

unsigned int

overAlloc = 0

)

Constructs an empty data block

Parameters

overAlloc

How many bytes of memory to overallocate

DataBlock

(

const DataBlock &

value

)

Copy constructor

Parameters

value

Data block to copy from

DataBlock	(	const DataBlock &	value,
		unsigned int	overAlloc
	)

Copy constructor with overallocation

Parameters

value	Data block to copy from
overAlloc	How many bytes of memory to overallocate

DataBlock	(	void *	value,
		unsigned int	len,
		bool	copyData = true,
		unsigned int	overAlloc = 0
	)

Constructs an initialized data block

Parameters

value	Data to assign, may be NULL to fill with zeros
len	Length of data, may be zero (then value is ignored)
copyData	True to make a copy of the data, false to just insert the pointer
overAlloc	How many bytes of memory to overallocate

virtual ~DataBlock ( )

virtual

Destroys the data, disposes the memory.

Member Function Documentation

void append ( void *  value, unsigned int  len  )

inline

Append data to the current block

Parameters

value	Data to append
len	Length of data

References DataBlock::clear().

Referenced by DataBlock::operator+=(), and Base64::operator<<().

void append

(

const DataBlock &

value

)

Append data to the current block

Parameters

value

Data to append

void append

(

const String &

value

)

Append a String to the current block

Parameters

value

String to append

DataBlock& assign	(	void *	value,
		unsigned int	len,
		bool	copyData = true,
		unsigned int	allocated = 0
	)

Assign data to the object

Parameters

value	Data to assign, may be NULL to fill with zeros
len	Length of data, may be zero (then value is ignored)
copyData	True to make a copy of the data, false to just insert the pointer
allocated	Real allocated data length in case it should not be copied

Referenced by DataBlock::resize().

int at ( unsigned int  offs, int  defvalue = -1  ) const

inline

Get the value of a single byte inside the stored data

Parameters

offs	Byte offset inside the stored data
defvalue	Default value to return if offset is outside data

Returns

Byte value at offset (0-255) or defvalue if offset outside data

Referenced by DataBlock::operator[]().

void clear

(

bool

deleteData = true

)

Clear the data and optionally free the memory

Parameters

deleteData

True to free the deta block, false to just forget it

Referenced by DataBlock::append().

bool convert	(	const DataBlock &	src,
		const String &	sFormat,
		const String &	dFormat,
		unsigned	maxlen = 0
	)

Convert data from a different format

Parameters

src	Source data block
sFormat	Name of the source format
dFormat	Name of the destination format
maxlen	Maximum amount to convert, 0 to use source

Returns

True if converted successfully, false on failure

void cut

(

int

len

)

Cut off a number of bytes from the data block

Parameters

len	Amount to cut, positive to cut from end, negative to cut from start of block

void* data ( ) const

inline

Get a pointer to the stored data.

Returns

A pointer to the data or NULL.

Referenced by RefStorage::data(), Cipher::decrypt(), Cipher::encrypt(), Hasher::hmac(), Hasher::hmacStart(), Cipher::initVector(), Cipher::setKey(), SliceVector< Obj >::unHexify(), Hasher::update(), Compressor::writeComp(), Stream::writeData(), and Compressor::writeDecomp().

unsigned char* data ( unsigned int  offs, unsigned int  len = 1  ) const

inline

Get a pointer to a byte range inside the stored data.

Parameters

offs	Byte offset inside the stored data
len	Number of bytes that must be valid starting at offset

Returns

A pointer to the data or NULL if the range is not available.

static const DataBlock& empty ( )

static

A static empty data block

virtual void* getObject ( const String &  name ) const

virtual

Get a pointer to a derived class given that class name

Parameters

name	Name of the class we are asking for

Returns

Pointer to the requested class or NULL if this object doesn't implement it

Reimplemented from GenObject.

void insert

(

const DataBlock &

value

)

Insert data before the current block

Parameters

value

Data to insert

unsigned int length ( ) const

inline

Get the length of the stored data.

Returns

The length of the stored data, zero for NULL.

Referenced by Cipher::decrypt(), Cipher::encrypt(), Hasher::hmac(), Hasher::hmacStart(), Cipher::initVector(), RefStorage::length(), MemoryStream::length(), DataBlock::resize(), Cipher::setKey(), SliceVector< Obj >::unHexify(), Hasher::update(), Compressor::writeComp(), Stream::writeData(), and Compressor::writeDecomp().

bool null ( ) const

inline

Checks if the block holds a NULL pointer.

Returns

True if the block holds NULL, false otherwise.

DataBlock& operator+= ( const DataBlock &  value )

inline

Appending operator.

References DataBlock::append().

DataBlock& operator+= ( const String &  value )

inline

Appending operator for Strings.

References DataBlock::append().

DataBlock& operator=

(

const DataBlock &

value

)

Assignment operator.

int operator[] ( signed int  index ) const

inline

Byte indexing operator with signed parameter

Parameters

index

Index of the byte to retrieve

Returns

Byte value at offset (0-255) or -1 if index outside data

References DataBlock::at().

int operator[] ( unsigned int  index ) const

inline

Byte indexing operator with unsigned parameter

Parameters

index

Index of the byte to retrieve

Returns

Byte value at offset (0-255) or -1 if index outside data

References DataBlock::at().

unsigned int overAlloc ( ) const

inline

Get the memory overallocation setting.

Returns

Amount of memory that will be overallocated.

void overAlloc ( unsigned int  bytes )

inline

Set the memory overallocation.

Parameters

bytes

How many bytes of memory to overallocate

void resize ( unsigned int  len )

inline

Resize (re-alloc or free) this block if required size is not the same as the current one

Parameters

len	Required block size

References DataBlock::assign(), and DataBlock::length().

String sqlEscape

(

char

extraEsc

)

const

Create an escaped string suitable for use in SQL queries

Parameters

extraEsc

Character to escape other than the default ones

Returns

A string with binary zeros and other special characters escaped

void truncate

(

unsigned int

len

)

Truncate the data block

Parameters

len	The maximum length to keep

bool unHexify	(	const char *	data,
		unsigned int	len,
		char	sep
	)

Build this data block from a hexadecimal string representation. Each octet must be represented in the input string with 2 hexadecimal characters. If a separator is specified, the octets in input string must be separated using exactly 1 separator. Only 1 leading or 1 trailing separators are allowed.

Parameters

data	Input character string
len	Length of the input string
sep	Separator character used between octets. 0 if no separator is expected

Returns

True if the input string was succesfully parsed, false otherwise

Referenced by SliceVector< Obj >::unHexify(), and DataBlock::unHexify().

bool unHexify	(	const char *	data,
		unsigned int	len
	)

Build this data block from a hexadecimal string representation. Each octet must be represented in the input string with 2 hexadecimal characters. This method guesses if separators are used. If so the octets in input string must be separated using exactly 1 separator. Only 1 leading or 1 trailing separators are allowed.

Parameters

data	Input character string
len	Length of the input string

Returns

True if the input string was succesfully parsed, false otherwise

bool unHexify ( const String &  data )

inline

Build this data block from a hexadecimal string representation. This version parses a String and guesses separators presence.

Parameters

data	Input character string

Returns

True if the input string was succesfully parsed, false otherwise

References String::c_str(), String::length(), and DataBlock::unHexify().

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

• yateclass.h