ArBasePacket Class Reference

#include <ArBasePacket.h>

Inheritance diagram for ArBasePacket:

List of all members.

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Detailed Description

Base packet class.

This class is a base class for all packets... most software will never need to use this class, it is there mostly to help people do more advanced client and server communications.

All of the functions are virtual so it can be completely overridden if desired... but the few most likely ones to be overridden are empty and makeFinal...

The theory of the packet works like this, the packet has a buffer, headerLength, footer length, readLength, length, and a maxLength. When the packet is initialized it is given a buffer and its maxLength. All of the functions that are somethingToBuf put data in at the current length of the packet, and advance the length. All of the functions that do bufToSomething get the data from where readLength points, and advance read length. If bufToSomething would go beyond the data length of the packet it returns a 0 (note that this includes if it goes into the footer length). resetRead sets readLength back to the header (since no one outside of the person who writes the class should touch the header). empty likewise sets the length back to the header since the header will be calculated in the finalizePacket method.

The base class and most classes of this kind will have an integer before the string, denoting the strings length... this is hidden by the function calls, but something someone may want to be aware of... it should not matter much as this same packet class should be used on both sides.

Uses of this class that don't get newed and deleted a lot can just go ahead and use the constructor with buf = NULL, as this will have the packet manage its own memory, making life easier.

Public Member Functions
	ArBasePacket (const ArBasePacket &other)
	Copy constructor.
	ArBasePacket (ArTypes::UByte2 bufferSize=0, ArTypes::UByte2 headerLength=0, char *buf=NULL, ArTypes::UByte2 footerLength=0)
	Constructor.
virtual ArTypes::Byte	bufToByte (void)
	Gets a ArTypes::Byte from the buffer.
virtual ArTypes::Byte2	bufToByte2 (void)
	Gets a ArTypes::Byte2 from the buffer.
virtual ArTypes::Byte4	bufToByte4 (void)
	Gets a ArTypes::Byte4 from the buffer.
virtual void	bufToData (unsigned char *data, int length)
	Gets length bytes from buffer and puts them into data.
virtual void	bufToData (char *data, int length)
	Gets length bytes from buffer and puts them into data.
virtual void	bufToStr (char *buf, int len)
	Gets a string from the buffer.
virtual ArTypes::UByte	bufToUByte (void)
	Gets a ArTypes::UByte from the buffer.
virtual ArTypes::UByte2	bufToUByte2 (void)
	Gets a ArTypes::UByte2 from the buffer.
virtual ArTypes::UByte4	bufToUByte4 (void)
	Gets a ArTypes::UByte4 from the buffer.
virtual void	byte2ToBuf (ArTypes::Byte2 val)
	Puts ArTypes::Byte2 into packets buffer.
virtual void	byte4ToBuf (ArTypes::Byte4 val)
	Puts ArTypes::Byte4 into packets buffer.
virtual void	byteToBuf (ArTypes::Byte val)
	Puts ArTypes::Byte into packets buffer.
virtual void	dataToBuf (const unsigned char *data, int length)
	Copies length bytes from data into packet buffer.
virtual void	dataToBuf (const char *data, int length)
	Copies length bytes from data into packet buffer.
virtual void	duplicatePacket (ArBasePacket *packet)
	Makes this packet a duplicate of another packet.
virtual void	empty (void)
	resets the length for more data to be added
virtual void	finalizePacket (void)
	MakeFinals the packet in preparation for sending, must be done.
virtual const char *	getBuf (void)
	Gets a pointer to the buffer the packet uses.
virtual ArTypes::UByte2	getDataLength (void)
	Gets the length of the data in the packet.
virtual ArTypes::UByte2	getDataReadLength (void)
	Gets how far into the data of the packet that has been read.
virtual ArTypes::UByte2	getFooterLength (void)
	Gets the length of the header.
virtual ArTypes::UByte2	getHeaderLength (void)
	Gets the length of the header.
virtual ArTypes::UByte2	getLength (void)
	Gets the total length of the packet.
virtual ArTypes::UByte2	getMaxLength (void)
	Gets the maximum length packet.
virtual ArTypes::UByte2	getReadLength (void)
	Gets how far into the packet that has been read.
virtual bool	isValid (void)
	Returns whether the packet is valid, i.e. no error has occurred when reading/writing.
virtual void	log (void)
	ArLogs the hex and decimal values of each byte of the packet, and possibly extra metadata as well.
ArBasePacket &	operator= (const ArBasePacket &other)
	Assignment operator.
virtual void	printHex (void)
	ArLogs the hex value of each byte in the packet.
virtual void	resetRead (void)
	Restart the reading process.
virtual void	resetValid ()
	Resets the valid state of the packet.
virtual void	setBuf (char *buf, ArTypes::UByte2 bufferSize)
	Sets the buffer the packet is using.
virtual bool	setHeaderLength (ArTypes::UByte2 length)
	Sets the length of the header.
virtual bool	setLength (ArTypes::UByte2 length)
	Sets the length of the packet.
virtual void	setMaxLength (ArTypes::UByte2 bufferSize)
	Sets the maximum buffer size (if new size is <= current does nothing).
virtual void	setReadLength (ArTypes::UByte2 readLength)
	Sets the read length.
virtual void	strNToBuf (const char *str, int length)
	Copies the given number of bytes from str into packet buffer.
virtual void	strToBuf (const char *str)
	Puts a NULL-terminated string into packet buffer.
virtual void	strToBufPadded (const char *str, int length)
	Copies length bytes from str, if str ends before length, pads data with 0s.
virtual void	uByte2ToBuf (ArTypes::UByte2 val)
	Puts ArTypes::UByte2 into packet buffer.
virtual void	uByte4ToBuf (ArTypes::UByte4 val)
	Puts ArTypes::UByte 4 into packet buffer.
virtual void	uByteToBuf (ArTypes::UByte val)
	Puts ArTypes::UByte into packets buffer.
virtual	~ArBasePacket ()
	Destructor.
Protected Member Functions
bool	hasWriteCapacity (int bytes)
	Returns true if there is enough room in the packet to add the specified number of bytes.
bool	isNextGood (int bytes)
Protected Attributes
char *	myBuf
ArTypes::UByte2	myFooterLength
ArTypes::UByte2	myHeaderLength
bool	myIsValid
ArTypes::UByte2	myLength
ArTypes::UByte2	myMaxLength
bool	myOwnMyBuf
ArTypes::UByte2	myReadLength

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Constructor & Destructor Documentation

ArBasePacket::ArBasePacket (  ArTypes::UByte2  bufferSize = 0, ArTypes::UByte2  headerLength = 0, char *  buf = NULL, ArTypes::UByte2  footerLength = 0 )

Constructor. Parameters: bufferSize  size of the buffer headerLength  length of the header buf  buffer packet uses, if NULL, instance will allocate memory footerLength  length of the footer following the data

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Member Function Documentation

void ArBasePacket::bufToData (  unsigned char *  data, int  length )  [virtual]

Gets length bytes from buffer and puts them into data. This was added to get around having to cast data you put in, since the data shouldn't really matter if its signed or unsigned. copies length bytes from the buffer into data, length is passed in, not read from packet Parameters: data  character array to copy the data into length  number of bytes to copy into data

void ArBasePacket::bufToData (  char *  data, int  length )  [virtual]

Gets length bytes from buffer and puts them into data. copies length bytes from the buffer into data, length is passed in, not read from packet Parameters: data  character array to copy the data into length  number of bytes to copy into data

void ArBasePacket::bufToStr (  char *  buf, int  len )  [virtual]

Gets a string from the buffer. Copy a string from the packet buffer into the given buffer, stopping when the end of the packet buffer is reached, the given length is reached, or a NUL character ('\0') is reached. If the given length is not large enough, then the remainder of the string is flushed from the packet. A NUL character ('\0') is appended to buf if there is sufficient room after copying the sting from the packet, otherwise no NUL is added (i.e. if len bytes are copied). Parameters: buf  Destination buffer len  Maximum number of characters to copy into the destination buffer

void ArBasePacket::dataToBuf (  const unsigned char *  data, int  length )  [virtual]

Copies length bytes from data into packet buffer. This was added to get around having to cast data you put in, since the data shouldn't really matter if its signed or unsigned. Parameters: data  chacter array to copy into buffer length  how many bytes to copy from data into packet

void ArBasePacket::dataToBuf (  const char *  data, int  length )  [virtual]

Copies length bytes from data into packet buffer. Parameters: data  chacter array to copy into buffer length  how many bytes to copy from data into packet

void ArBasePacket::duplicatePacket (  ArBasePacket *  packet  )  [virtual]

Makes this packet a duplicate of another packet. Copies the given packets buffer into the buffer of this packet, also sets this length and readlength to what the given packet has Parameters: packet  the packet to duplicate

void ArBasePacket::empty (  void   )  [virtual]

resets the length for more data to be added Sets the packet length back to be the packets header length again

bool ArBasePacket::isValid (  void   )  [virtual]

Returns whether the packet is valid, i.e. no error has occurred when reading/writing. A packet is considered "invalid" if an attempt is made to write too much data into the packet, or to read too much data from the packet. Calls to empty() and resetRead() will restore the valid state.

void ArBasePacket::resetRead (  void   )  [virtual]

Restart the reading process. Sets the length read back to the header length so the packet can be reread using the other methods

void ArBasePacket::resetValid (   )  [virtual]

Resets the valid state of the packet. Resets the packet to the "valid" state. This method should generally only be called externally when the application has taken some recovery action. For example, if an attempt to write a long string to the packet fails (and isValid() returns false), then a smaller string may be written instead.

void ArBasePacket::strNToBuf (  const char *  str, int  length )  [virtual]

Copies the given number of bytes from str into packet buffer. Deprecated: use strToBufPadded(), strToBuf(), or dataToBuf() instead

void ArBasePacket::strToBuf (  const char *  str  )  [virtual]

Puts a NULL-terminated string into packet buffer. Parameters: str  string to copy into buffer

void ArBasePacket::strToBufPadded (  const char *  str, int  length )  [virtual]

Copies length bytes from str, if str ends before length, pads data with 0s. If string ends before length it pads the string with NUL ('\0') characters. Parameters: str  character array to copy into buffer length  how many bytes to copy from the str into packet

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

• ArBasePacket.h
• ArBasePacket.cpp

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