Provides stream like read access to a memory buffer. More...

#include <CzDataIO.h>

Public Member Functions
	CzDataInput (bool managed)
	CzDataInput ()
virtual	~CzDataInput ()
bool	Init (int length)
	Initialises the stream object.
virtual void	Release ()
	Releases the stream object.
char *	getData ()
void	setData (char *data)
	Sets the stream data.
void	setData (char *data, int length)
	Sets the stream data and its length.
void	setManaged (bool managed)
bool	isManaged () const
int	Skip (int num_bytes)
	Moves the stream pointer back and forth.
int	setPos (int pos)
	Sets the stream position.
int	getPos () const
int	getLength () const
bool	isEOF () const
int	Remaining () const
char	getByte ()
	Gets the next byte from the stream.
float	getByteAsFloat ()
	Gets the next byte from the stream as a float.
unsigned char	getUByte ()
	Gets the next byte from the stream as an unsigned byte.
int	getUByteAsInt ()
	Gets the next byte from the stream as an integer.
float	getUByteAsFloat ()
	Gets the next byte from the stream as an unsigned float.
int	getBytes (char *data, int count)
	Gets count bytes from the stream.
int	getBytes (short *data, int count)
	Gets count bytes from the stream and writes them into a short buffer.
int	getBytes (int *data, int count)
	Gets count bytes from the stream and writes them into an int buffer.
int	getBytes (float *data, int count)
	Gets count bytes from the stream and writes them into a float buffer.
int	getUBytes (unsigned char *data, int count)
int	getUBytes (int *data, int count)
	Gets count unsigned bytes from the stream and writes them into an int buffer.
int	getUBytes (float *data, int count)
	Gets count unsigned bytes from the stream and writes them into a float buffer.
int	getChars (char *data, int count)
	Gets count chars from the stream and writes them into a char buffer.
short	getShort ()
	Gets the next short from the stream.
short	getShortSwab ()
float	getShortAsFloat ()
	Gets the next short from the buffer as a float.
int	getUShort ()
	Gets the next unsigned short from the stream.
float	getUShortAsFloat ()
	Gets the next unsigned short as a float.
int	getShorts (short *data, int count)
	Gets count shorts from the stream and writes them into a short buffer.
int	getShorts (int *data, int count)
	Gets count shorts from the stream and writes them into an int buffer.
int	getShorts (float *data, int count)
	Gets count shorts from the stream and writes them into a float buffer.
int	getUShorts (unsigned short *data, int count)
	Gets count unsigned shorts from the stream and writes them into an unsigned short buffer.
int	getUShorts (int *data, int count)
	Gets count unsigned shorts from the stream and writes them into an int buffer.
int	getUShorts (float *data, int count)
	Gets count unsigned shorts from the stream and writes them into a float buffer.
int	getInt ()
	Gets the next int from the stream.
int	getIntSwab ()
	Gets the next int from the stream, swapping the byte order.
int	getInts (int *data, int count)
	Gets count ints from the stream and writes them into an int buffer.
int	getInts (float *data, int count)
	Gets count ints from the stream and writes them into a float buffer.
float	getFloat ()
	Gets the next float from the stream.
bool	getNextString (CzString *pString)
	Gets the next string.
bool	getNextString (char *pString, int max_len)
	Gets the next string, searching max_len chars forward in the stream.
bool	getNextQuotedStringAsint (int *pNum)
	Gets the the next quoted string as an integer.
bool	getNextQuotedString (CzString *pString)
	Gets the next quoted string.
bool	getNextQuotedString (char *pString, int max_len)
	Gets the next quoted string, searching max_len chars forward in the stream.
bool	getNextOccuranceOf (char chr)
	Skips teh stream to the next occurance of the specified character.
int	getNextTag (char tag_start_char, char tag_end_char, int range, int &start_pos)
	Gets the next tag marked by tag_start_char and tag_end_char tag chars.
int	getNextTagOrValue (char tag_start_char, char tag_end_char, int range, int &start_pos)
	Gets the next tag marked by tag_start_char and tag_end_char tag chars or value.
int	FindString (const char *pString, int str_len) const
	Searches forward for a string.
int	SkipToWhitespaceInTag ()
	Skips stream to next available whitespace character in an XML tag.
int	SkipToNoneWhitespaceInTag ()
	Skip stream to next none whitespace character in an XML tag.
int	SkipToCharInTag (char chr)
	Skip to character in tag.
int	getLineNumber (int pos) const
	Gets line number of the specified stream position (assumes the stream is text).
int	CalculateCheckSum ()
	Calculates the check sum of teh strean.
bool	StripXMLComments ()
	Strip XML comments from the stream.
bool	CountXmlEntities (int &tags, int &attributes)
	Count the number of XML tags an attributes entities present in the stream.
Protected Attributes
char *	Data
	Streams data.
int	Position
	Current position in stream.
int	Length
	Length of stream (actual allocated memory sie is aligned to 32 bytes)
bool	EndOfFile
	true if end of stream reached
bool	Managed
	If true data buffer will not be released when object deleted.

Detailed Description

Provides stream like read access to a memory buffer.

From the perspective of AppEasy a stream is data that can be read from or written to. When data is read from a stream, the position at which we read the next lot of data moves to the end of the previously read data. Streams have a stream pointer / position which marks the place where new data will be read or written.

AppEasy provides two simple classes that allow you to treat memory as though it was a stream. This can come in very useful when serialising binary data or parsing data located in a memory buffer.

Two classes are provided which provide support for input and output:

CzDataInput - Input stream access to a a memory buffer
CzDataOutput - Output stream access to a a memory buffer

Lets take a look at an example showing how to use :

// Create and initialise an input stream of 1024 bytes
CzDataInput *stream  = new CzDataInput();
stream->Init(1024);

// Read some data into the stream
if (!file->Read(stream->getData(), size))
    return -1;

// Do something with the data
while (!in->isEOF())
{
    char b = getByte();
}

Constructor & Destructor Documentation

CzDataInput::CzDataInput ( bool managed ) [inline]

CzDataInput::CzDataInput ( ) [inline]

virtual CzDataInput::~CzDataInput ( ) [inline, virtual]

Member Function Documentation

int CzDataInput::CalculateCheckSum ( )

Calculates the check sum of teh strean.

Returns:: The calculated check sum.

bool CzDataInput::CountXmlEntities	(	int &	tags,
		int &	attributes
	)

Count the number of XML tags an attributes entities present in the stream.

Parameters:

[out]	tags	The number of tags found.
[out]	attributes	The number of attributes found.

Returns:: The total number of XML entities.

int CzDataInput::FindString	(	const char *	pString,
		int	str_len
	)		const

Searches forward for a string.

Parameters:

pString	The string to find.
str_len	The length of the string.

Returns:: The length of the found string or < 0 for not found.

char CzDataInput::getByte ( )

Gets the next byte from the stream.

Returns:: The byte.

float CzDataInput::getByteAsFloat ( )

Gets the next byte from the stream as a float.

Returns:: The byte as float.

int CzDataInput::getBytes	(	char *	data,
		int	count
	)

Gets count bytes from the stream.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number of bytes read or 0 for EOF.

int CzDataInput::getBytes	(	short *	data,
		int	count
	)

Gets count bytes from the stream and writes them into a short buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number of bytes read or 0 for EOF.

int CzDataInput::getBytes	(	int *	data,
		int	count
	)

Gets count bytes from the stream and writes them into an int buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number of bytes read or 0 for EOF.

int CzDataInput::getBytes	(	float *	data,
		int	count
	)

Gets count bytes from the stream and writes them into a float buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number of bytes read or 0 for EOF.

int CzDataInput::getChars	(	char *	data,
		int	count
	)

Gets count chars from the stream and writes them into a char buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number chars read or 0 for EOF.

char* CzDataInput::getData ( ) [inline]

float CzDataInput::getFloat ( )

Gets the next float from the stream.

Returns:: The float.

int CzDataInput::getInt ( )

Gets the next int from the stream.

Returns:: The int.

int CzDataInput::getInts	(	int *	data,
		int	count
	)

Gets count ints from the stream and writes them into an int buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of ints to read.

Returns:: The number of ints read or 0 for EOF.

int CzDataInput::getInts	(	float *	data,
		int	count
	)

Gets count ints from the stream and writes them into a float buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of ints to read.

Returns:: The number of ints read or 0 for EOF.

int CzDataInput::getIntSwab ( )

Gets the next int from the stream, swapping the byte order.

Returns:: The int.

int CzDataInput::getLength ( ) const [inline]

int CzDataInput::getLineNumber ( int pos ) const

Gets line number of the specified stream position (assumes the stream is text).

Parameters:

pos	The position.

Returns:: The line number.

bool CzDataInput::getNextOccuranceOf ( char chr )

Skips teh stream to the next occurance of the specified character.

Parameters:

chr	The character to find.

Returns:: true if it succeeds, false if it fails.

bool CzDataInput::getNextQuotedString ( CzString * pString )

Gets the next quoted string.

Parameters:

[in,out] pString If non-null, the string.

Returns:: true if it succeeds, false if it fails.

bool CzDataInput::getNextQuotedString	(	char *	pString,
		int	max_len
	)

Gets the next quoted string, searching max_len chars forward in the stream.

Parameters:

[out]	pString	If non-null, the string.
	max_len	Maximum chars to search forwards.

Returns:: true if it succeeds, false if it fails.

bool CzDataInput::getNextQuotedStringAsint ( int * pNum )

Gets the the next quoted string as an integer.

Parameters:

[out] pNum If non-null, address of integer variable.

Returns:: true if it succeeds, false if it fails.

bool CzDataInput::getNextString ( CzString * pString )

Gets the next string.

Parameters:

[out] pString If non-null, the string.

Returns:: true if it succeeds, false if it fails.

bool CzDataInput::getNextString	(	char *	pString,
		int	max_len
	)

Gets the next string, searching max_len chars forward in the stream.

Parameters:

[out]	pString	If non-null, the string.
	max_len	Maximum chars to search forwards.

Returns:: true if it succeeds, false if it fails.

int CzDataInput::getNextTag	(	char	tag_start_char,
		char	tag_end_char,
		int	range,
		int &	start_pos
	)

Gets the next tag marked by tag_start_char and tag_end_char tag chars.

For example, if tag_start_char = "<" and tag_end_char = ">" then the next XML tag will be found.

Parameters:

	tag_start_char	The tag start character.
	tag_end_char	The tag end character.
	range	Number of characters to search forwards.
[in,out]	start_pos	Stream position where tag starts.

Returns:: Length of tag or < 0 for not found.

int CzDataInput::getNextTagOrValue	(	char	tag_start_char,
		char	tag_end_char,
		int	range,
		int &	start_pos
	)

Gets the next tag marked by tag_start_char and tag_end_char tag chars or value.

For example, if tag_start_char = "<" and tag_end_char = ">" then the next XML tag will be found.

Parameters:

	tag_start_char	The tag start character.
	tag_end_char	The tag end character.
	range	Number of characters to search forwards.
[in,out]	start_pos	Stream position where tag starts.

Returns:: Length of tag or < 0 for not found.

int CzDataInput::getPos ( ) const [inline]

short CzDataInput::getShort ( )

Gets the next short from the stream.

Gets the next short from the stream, swapping the byte order.

Returns:: The short.

float CzDataInput::getShortAsFloat ( )

Gets the next short from the buffer as a float.

Returns:: The short as a float.

int CzDataInput::getShorts	(	short *	data,
		int	count
	)

Gets count shorts from the stream and writes them into a short buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of shorts to read.

Returns:: The number of shorts read or 0 for EOF.

int CzDataInput::getShorts	(	int *	data,
		int	count
	)

Gets count shorts from the stream and writes them into an int buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of shorts to read.

Returns:: The number of shorts read or 0 for EOF.

int CzDataInput::getShorts	(	float *	data,
		int	count
	)

Gets count shorts from the stream and writes them into a float buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of shorts to read.

Returns:: The number of shorts read or 0 for EOF.

short CzDataInput::getShortSwab ( )

unsigned char CzDataInput::getUByte ( )

Gets the next byte from the stream as an unsigned byte.

Returns:: The unsigned byte.

float CzDataInput::getUByteAsFloat ( )

Gets the next byte from the stream as an unsigned float.

Returns:: The byte as an unsigned float.

int CzDataInput::getUByteAsInt ( )

Gets the next byte from the stream as an integer.

Returns:: The byte as an int.

int CzDataInput::getUBytes	(	unsigned char *	data,
		int	count
	)

int CzDataInput::getUBytes	(	int *	data,
		int	count
	)

Gets count unsigned bytes from the stream and writes them into an int buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number of bytes read or 0 for EOF.

int CzDataInput::getUBytes	(	float *	data,
		int	count
	)

Gets count unsigned bytes from the stream and writes them into a float buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of bytes to read.

Returns:: The number of bytes read or 0 for EOF.

int CzDataInput::getUShort ( )

Gets the next unsigned short from the stream.

Returns:: The unsigned short.

float CzDataInput::getUShortAsFloat ( )

Gets the next unsigned short as a float.

Returns:: The unsigned short as a float.

int CzDataInput::getUShorts	(	unsigned short *	data,
		int	count
	)

Gets count unsigned shorts from the stream and writes them into an unsigned short buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of shorts to read.

Returns:: The number of shorts read or 0 for EOF.

int CzDataInput::getUShorts	(	int *	data,
		int	count
	)

Gets count unsigned shorts from the stream and writes them into an int buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of shorts to read.

Returns:: The number of shorts read or 0 for EOF.

int CzDataInput::getUShorts	(	float *	data,
		int	count
	)

Gets count unsigned shorts from the stream and writes them into a float buffer.

Parameters:

[out]	data	If non-null, destination data.
	count	Number of shorts to read.

Returns:: The number of shorts read or 0 for EOF.

bool CzDataInput::Init ( int length )

Initialises the stream object.

Allocates a memory buffer of the specified length and sets the stream market to the start

Parameters:

length The stream length.

Returns:: true if it succeeds, false if it fails.

bool CzDataInput::isEOF ( ) const [inline]

bool CzDataInput::isManaged ( ) const [inline]

void CzDataInput::Release ( ) [virtual]

Releases the stream object.

Deletes the memory associated with the stream

int CzDataInput::Remaining ( ) const [inline]

void CzDataInput::setData ( char * data )

Sets the stream data.

Sets the data stream, taking ownership of the supplied data. If the stream already has data assigned then it will be deleted.

Parameters:

[in] data If non-null, the data stream.

void CzDataInput::setData	(	char *	data,
		int	length
	)

Sets the stream data and its length.

Sets the data stream, taking ownership of the supplied data. The length of the stream is also set to the supplied length. If the stream already has data assigned then it will be deleted.

Parameters:

[in]	data	If non-null, the data.
	length	The length of the data.

void CzDataInput::setManaged ( bool managed ) [inline]

int CzDataInput::setPos ( int pos )

Sets the stream position.

Parameters:

pos	The stream position.

Returns:: Stream position.

int CzDataInput::Skip ( int num_bytes )

Moves the stream pointer back and forth.

Skips te supplied number of bytes in the stream, num_bytes can be negative. Attempted to skip past the start or end of teh stream will cause EOF.

Parameters:

num_bytes Number of bytes.

Returns:: Stream position.

int CzDataInput::SkipToCharInTag ( char chr )

Skip to character in tag.

Parameters:

chr	The character.

Returns:: Stream position of character or < 0 not found.

int CzDataInput::SkipToNoneWhitespaceInTag ( )

Skip stream to next none whitespace character in an XML tag.

Returns:: Stream position of none whitespace or < 0 not found.

int CzDataInput::SkipToWhitespaceInTag ( )

Skips stream to next available whitespace character in an XML tag.

Returns:: Stream position of whitespace or < 0 not found.

bool CzDataInput::StripXMLComments ( )

Strip XML comments from the stream.

Returns:: true if it succeeds, false if it fails.

Member Data Documentation

char* CzDataInput::Data [protected]

Streams data.

bool CzDataInput::EndOfFile [protected]

true if end of stream reached

int CzDataInput::Length [protected]

Length of stream (actual allocated memory sie is aligned to 32 bytes)

bool CzDataInput::Managed [protected]

If true data buffer will not be released when object deleted.

int CzDataInput::Position [protected]

Current position in stream.

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

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation