TcpSocket::CircularBuffer Class Reference
[Internal utility]

Buffer class containing one read/write circular buffer. More...

#include <TcpSocket.h>


Public Member Functions
	CircularBuffer (size_t size)
	~CircularBuffer ()
bool	Write (const char *p, size_t l)
	append l bytes from p to buffer
bool	Read (char *dest, size_t l)
	copy l bytes from buffer to dest
bool	Remove (size_t l)
	skip l bytes from buffer
std::string	ReadString (size_t l)
	read l bytes from buffer, returns as string.
size_t	GetLength ()
	total buffer length
const char *	GetStart ()
	pointer to circular buffer beginning
size_t	GetL ()
	return number of bytes from circular buffer beginning to buffer physical end
size_t	Space ()
	return free space in buffer, number of bytes until buffer overrun
unsigned long	ByteCounter (bool clear=false)
	return total number of bytes written to this buffer, ever
Private Member Functions
	CircularBuffer (const CircularBuffer &s)
CircularBuffer &	operator= (const CircularBuffer &)
Private Attributes
char *	buf
size_t	m_max
size_t	m_q
size_t	m_b
size_t	m_t
unsigned long	m_count

Detailed Description

Buffer class containing one read/write circular buffer.

Definition at line 66 of file TcpSocket.h.

Constructor & Destructor Documentation

TcpSocket::CircularBuffer::CircularBuffer ( size_t size )

Definition at line 1524 of file TcpSocket.cpp.

01525 :buf(new char[2 * size])
01526 ,m_max(size)
01527 ,m_q(0)
01528 ,m_b(0)
01529 ,m_t(0)
01530 ,m_count(0)
01531 {
01532 }

TcpSocket::CircularBuffer::~CircularBuffer ( )

Definition at line 1535 of file TcpSocket.cpp.

01536 {
01537         delete[] buf;
01538 }

TcpSocket::CircularBuffer::CircularBuffer ( const CircularBuffer & s ) [inline, private]

Definition at line 94 of file TcpSocket.h.

00094 {}

Member Function Documentation

bool TcpSocket::CircularBuffer::Write	(	const char *	p,
		size_t	l
	)

append l bytes from p to buffer

Definition at line 1541 of file TcpSocket.cpp.

References m_count, m_max, m_q, and m_t.

Referenced by TcpSocket::OnRead().

01542 {
01543         if (m_q + l > m_max)
01544         {
01545                 return false; // overflow
01546         }
01547         m_count += (unsigned long)l;
01548         if (m_t + l > m_max) // block crosses circular border
01549         {
01550                 size_t l1 = m_max - m_t; // size left until circular border crossing
01551                 // always copy full block to buffer(buf) + top pointer(m_t)
01552                 // because we have doubled the buffer size for performance reasons
01553                 memcpy(buf + m_t, s, l);
01554                 memcpy(buf, s + l1, l - l1);
01555                 m_t = l - l1;
01556                 m_q += l;
01557         }
01558         else
01559         {
01560                 memcpy(buf + m_t, s, l);
01561                 memcpy(buf + m_max + m_t, s, l);
01562                 m_t += l;
01563                 if (m_t >= m_max)
01564                         m_t -= m_max;
01565                 m_q += l;
01566         }
01567         return true;
01568 }

bool TcpSocket::CircularBuffer::Read	(	char *	dest,
		size_t	l
	)

copy l bytes from buffer to dest

Definition at line 1571 of file TcpSocket.cpp.

References m_b, m_max, m_q, and m_t.

Referenced by TcpSocket::OnSocks4Read(), TcpSocket::ReadInput(), ReadString(), and Remove().

01572 {
01573         if (l > m_q)
01574         {
01575                 return false; // not enough chars
01576         }
01577         if (m_b + l > m_max) // block crosses circular border
01578         {
01579                 size_t l1 = m_max - m_b;
01580                 if (s)
01581                 {
01582                         memcpy(s, buf + m_b, l1);
01583                         memcpy(s + l1, buf, l - l1);
01584                 }
01585                 m_b = l - l1;
01586                 m_q -= l;
01587         }
01588         else
01589         {
01590                 if (s)
01591                 {
01592                         memcpy(s, buf + m_b, l);
01593                 }
01594                 m_b += l;
01595                 if (m_b >= m_max)
01596                         m_b -= m_max;
01597                 m_q -= l;
01598         }
01599         if (!m_q)
01600         {
01601                 m_b = m_t = 0;
01602         }
01603         return true;
01604 }

bool TcpSocket::CircularBuffer::Remove ( size_t l )

skip l bytes from buffer

Definition at line 1607 of file TcpSocket.cpp.

References Read().

01608 {
01609         return Read(NULL, l);
01610 }

std::string TcpSocket::CircularBuffer::ReadString ( size_t l )

read l bytes from buffer, returns as string.

Definition at line 1649 of file TcpSocket.cpp.

References Read().

01650 {
01651         char *sz = new char[l + 1];
01652         if (!Read(sz, l)) // failed, debug printout in Read() method
01653         {
01654                 delete[] sz;
01655                 return "";
01656         }
01657         sz[l] = 0;
01658         std::string tmp = sz;
01659         delete[] sz;
01660         return tmp;
01661 }

size_t TcpSocket::CircularBuffer::GetLength ( )

total buffer length

Definition at line 1613 of file TcpSocket.cpp.

References m_q.

Referenced by TcpSocket::GetInputLength().

01614 {
01615         return m_q;
01616 }

const char * TcpSocket::CircularBuffer::GetStart ( )

pointer to circular buffer beginning

Definition at line 1619 of file TcpSocket.cpp.

References m_b.

01620 {
01621         return buf + m_b;
01622 }

size_t TcpSocket::CircularBuffer::GetL ( )

return number of bytes from circular buffer beginning to buffer physical end

Definition at line 1625 of file TcpSocket.cpp.

References m_b, m_max, and m_q.

01626 {
01627         return (m_b + m_q > m_max) ? m_max - m_b : m_q;
01628 }

size_t TcpSocket::CircularBuffer::Space ( )

return free space in buffer, number of bytes until buffer overrun

Definition at line 1631 of file TcpSocket.cpp.

References m_max, and m_q.

01632 {
01633         return m_max - m_q;
01634 }

unsigned long TcpSocket::CircularBuffer::ByteCounter ( bool clear = false )

return total number of bytes written to this buffer, ever

Definition at line 1637 of file TcpSocket.cpp.

References m_count.

01638 {
01639         if (clear)
01640         {
01641                 unsigned long x = m_count;
01642                 m_count = 0;
01643                 return x;
01644         }
01645         return m_count;
01646 }