Manage TCP sockets. More...

#include <mcs.hh>

Inheritance diagram for mcs::Socket:

Public Member Functions
void	Close ()
	Close the socket. More...

string	getline ()
	Reads from a socket until a newline is encountered. More...

Socket &	operator= (const Socket &)
	Declared to avoid using of default assignment operator. More...

void	print (string s)
	Writes a string in the socket adding a newline. More...

unsigned int	read (void *buf, unsigned int count)
	Reads data from the socket and write in a buffer. More...

unsigned int	recvData (char **buffer, unsigned int maxsize)
	Receive data and store in a buffer. More...

unsigned int	recvData (string filename)
	Receive data and write to a file. More...

unsigned int	recvData (int filedes)
	Receive data and write to a file descriptor. More...

unsigned int	recvData (ofstream &stream)
	Receive data and write to a ofstream object. More...

void	sendData (Serializable *from)
	Send a block of data through the socket. More...

	Socket (const Socket &)
	Declared to avoid using of default copy constructor. More...

	Socket (string host, unsigned short int port=0, unsigned int readTimeout=1000, unsigned int writeTimeout=1000, bool ssl=false)
	Constructor, to create a new connection. More...

	Socket (int sockfd, unsigned int readTimeout=1000, unsigned int writeTimeout=1000, void *ssl_ctx=NULL)
	Constructor based on an already existent socket. More...

unsigned int	write (void *buf, unsigned int count)
	Reads data from a buffer and write in the socket. More...

	~Socket ()
	Destructor. More...

Public Member Functions inherited from mcs::HostInfo
	HostInfo (const HostInfo &)
	Declared to avoid using of default copy constructor. More...

	HostInfo (string host)
	Constructor. More...

	HostInfo (int sockfd)
	Constructor, to obtain information from an already connected socket. More...

string	hostname ()
	Return the host name. More...

string	ipaddress ()
	Return the host IP address. More...

HostInfo &	operator= (const HostInfo &)
	Declared to avoid using of default assignment operator. More...

	~HostInfo ()
	Destructor. More...

Static Public Member Functions
static void	set_struct_timeval (unsigned int millisec, struct timeval *time)
	Fill a "struct timeval" with the given interval. More...

Protected Member Functions
bool	chkRecv (bool chkDataAvailable=false, enum ThrowExceptions throwexc=THROW)
	Check if you can read data from this socket. More...

bool	chkSend (enum ThrowExceptions throwexc=THROW)
	Check if you can send data through this socket. More...

Protected Member Functions inherited from mcs::HostInfo
void	populate_sockaddr_in ()

Private Member Functions
unsigned int	recvChunk (void *buf, unsigned int size)
	Receive a chunk of binary data from the socket. More...

unsigned int	recvChunk (Buffer *buf)
	Same as recvChunk(void*, unsigned int) but stores data in the AccumBuffer object passed as parameter. More...

void	sendChunk (void *buf, unsigned int size)
	Send a chunk of binary data through the socket. More...

int	socketToHost (unsigned short port)
	Connect to the host. More...

Private Attributes
fd_set	fds
	Set of socket file descriptors, used with select(). More...

	MCS_DEBUG_ALLOC

unsigned short int	port
	Port on which this socket will connect. More...

struct timeval	readto
	Timeout interval for read operations. More...

int	sockfd
	C socket file descriptor. More...

bool	use_ssl
	True if the connection should be encrypted. More...

struct timeval	writeto
	Timeout interval fro write operations. More...

Additional Inherited Members
Protected Attributes inherited from mcs::HostInfo
string	host

string	ipaddr

struct sockaddr_in	sin

Detailed Description

Manage TCP sockets.

This class implements a TCP socket. It has a timeout facility, as well as a mechanism to check that a connection is still open and ready to send/receive data. It is strongly recommended that the program ignores all SIGPIPE signals for this to work correctly, this can be done in the main program with:

#include <signal.h>
...
signal(SIGPIPE, SIG_IGN);

Definition at line 1662 of file mcs.hh.

Constructor & Destructor Documentation

◆ Socket() [1/3]

mcs::Socket::Socket ( const Socket & )

Declared to avoid using of default copy constructor.

This constructor is declared but not implemented. If you try to use it you will get a compilation error.

◆ Socket() [2/3]

mcs::Socket::Socket	(	string	host,
		unsigned short int	port = `0`,
		unsigned int	readTimeout = `1000`,
		unsigned int	writeTimeout = `1000`,
		bool	ssl = `false`
	)

Constructor, to create a new connection.

This creates a new socket connecting to a specified host and port. It is possible to specify read and write timeout for the newly created socket. This can throw Event exceptions if the connection cannot be made.

Parameters

host	Host name to connect to;
port	Port to connect to;
readTimeout	Timeout for reading operations, in millisecond;
writeTimeout	Timeout for writing operations, in millisecond;
ssl	If the socket should use a secure connection.

Definition at line 242 of file Socket.cc.

◆ Socket() [3/3]

mcs::Socket::Socket	(	int	sockfd,
		unsigned int	readTimeout = `1000`,
		unsigned int	writeTimeout = `1000`,
		void *	ssl_ctx = `NULL`
	)

Constructor based on an already existent socket.

This creates a new Socket object based on an already existent socket, provided, for example, from a ServerSocket object. It is possible to specify read and write timeout for the newly created socket.

Parameters

sockfd	The C socket file descriptor;
readTimeout	Timeout for reading operations, in millisecond;
writeTimeout	Timeout for writing operations, in millisecond.
ssl_ctx	The SSL context object, if the socket should use a secure connection.

Definition at line 297 of file Socket.cc.

◆ ~Socket()

mcs::Socket::~Socket ( )

Destructor.

This flushes the socket with a write timeout, then close the socket.

Definition at line 362 of file Socket.cc.

Member Function Documentation

◆ chkRecv()

bool mcs::Socket::chkRecv	(	bool	chkDataAvailable = `false`,
		enum ThrowExceptions	throwexc = `THROW`
	)

protected

Check if you can read data from this socket.

This is just a check that should be made just before any read from the socket. Depending on the throwexc it will throw a FATAL exception or return false if the remote socket has been closed or timed out.

Parameters

chkDataAvailable	Will set timeout to zero, so that it will only check for data availability without waiting.
throwexc	If DONT_THROW will return false instead of throwing an exception.

Returns: True if its possible to read from the socket, false otherwise.

Exceptions

FATAL	MSG_CALLING_SELECT;
FATAL	MSG_TIME_OUT;
FATAL	MSG_CALLING_RECV;
FATAL	MSG_CLOSED_BY_PEER;
FATAL	MSG_UNEXPECTED.

Definition at line 419 of file Socket.cc.

◆ chkSend()

bool mcs::Socket::chkSend ( enum ThrowExceptions throwexc = THROW )

protected

Check if you can send data through this socket.

This is just a check that should be made just before any write to the socket.

Parameters

throwexc If DONT_THROW will return false instead of throwing an exception.

Returns: True if its possible to write in the socket, false otherwise.

Exceptions

FATAL	MSG_CALLING_SELECT;
FATAL	MSG_TIME_OUT;
FATAL	MSG_UNEXPECTED.

Definition at line 387 of file Socket.cc.

◆ Close()

void mcs::Socket::Close ( )

Close the socket.

Definition at line 368 of file Socket.cc.

◆ getline()

string mcs::Socket::getline ( )

Reads from a socket until a newline is encountered.

Internally calls chkRecv, so this can throw exceptions if the socket has been closed or the operation had timed out.

Returns: a A string containing the data read without the newline.

Warning: Don't use this if you want to receive binary data.

Definition at line 615 of file Socket.cc.

◆ operator=()

Socket& mcs::Socket::operator= ( const Socket & )

Declared to avoid using of default assignment operator.

Warning: This operator is declared but not implemented. If you try to use

◆ print()

void mcs::Socket::print ( string s )

Writes a string in the socket adding a newline.

Internally calls chkSend, so this can throw exceptions if the socket has been closed.

Parameters

s	The string containing the data to be send.

Warning: Don't use this if you want to send binary data.

Definition at line 630 of file Socket.cc.

◆ read()

unsigned int mcs::Socket::read	(	void *	buf,
		unsigned int	count
	)

Reads data from the socket and write in a buffer.

This will read count bytes from the socket and write in the memory buffer pointed by buf. It checks socket availability with chkRecv().

Parameters

buf	Buffer to store data;
count	Number of bytes to read from the socket.

Returns: Number of bytes actually read.

Exceptions

FATAL MSG_CLOSED_BY_PEER.

Definition at line 546 of file Socket.cc.

◆ recvChunk() [1/2]

unsigned int mcs::Socket::recvChunk	(	void *	buf,
		unsigned int	size
	)

private

Receive a chunk of binary data from the socket.

This method receives a chunk of binary data from another mcs::Socket object attached to the other side of the socket, using the MCS protocol. On the other side the Socket object should send data with the Socket.sendChunk() method.

Parameters

buf	Pointer to a buffer where store data, this buffer must be big at least "size" bytes;
size	Size of data received.

Exceptions

MCS_FATAL	MSG_PROTOCOL;
MCS_FATAL	MSG_NOT_ENOUGH_SPACE.

Definition at line 496 of file Socket.cc.

◆ recvChunk() [2/2]

unsigned int mcs::Socket::recvChunk ( Buffer * buf )

private

Same as recvChunk(void*, unsigned int) but stores data in the AccumBuffer object passed as parameter.

Definition at line 520 of file Socket.cc.

◆ recvData() [1/4]

unsigned int mcs::Socket::recvData	(	char **	buffer,
		unsigned int	maxsize
	)

Receive data and store in a buffer.

If the buffer is not yet created it will be automatically allocated. In this case it is the user responsibility to free the buffer after use. Note that this buffer will contain all data, not just a chunk. The method will consider the buffer allocated if buffer is not NULL, and will write in that buffer. The second parameter tells the size of the buffer, and must be large enough to store all data otherwise an exception will be thrown.

Parameters

buffer	Address of a pointer to the buffer;
maxsize	Size of the buffer, if already allocated.

Returns: Size of the data written in the buffer.

Exceptions

MCS_FATAL	MSG_PROTOCOL;
MCS_FATAL	MSG_NOT_ENOUGH_SPACE.

Definition at line 662 of file Socket.cc.

◆ recvData() [2/4]

unsigned int mcs::Socket::recvData ( string filename )

Receive data and write to a file.

Parameters

filename File to be written.

Returns: Size of the data written in the file.

Exceptions

MCS_FATAL	MSG_PROTOCOL;
MCS_FATAL	MSG_CANT_OPEN_FILE.

Definition at line 723 of file Socket.cc.

◆ recvData() [3/4]

unsigned int mcs::Socket::recvData ( int filedes )

Receive data and write to a file descriptor.

Parameters

filedes libc's file descriptor.

Returns: Size of the data written in the file.

Exceptions

MCS_FATAL MSG_PROTOCOL;

Definition at line 757 of file Socket.cc.

◆ recvData() [4/4]

unsigned int mcs::Socket::recvData ( ofstream & stream )

Receive data and write to a ofstream object.

Parameters

stream C++ ofstream object.

Returns: Size of the data written in the file.

Exceptions

MCS_FATAL MSG_PROTOCOL;

Definition at line 733 of file Socket.cc.

◆ sendChunk()

void mcs::Socket::sendChunk	(	void *	buf,
		unsigned int	size
	)

private

Send a chunk of binary data through the socket.

This method send a chunk of binary data to another mcs::Socket object attached to the other side of the socket, using the MCS protocol. On the other side the Socket object should be waiting for data in the Socket.recvChunk() method.

Parameters

buf	Pointer to data to send;
size	Size of the buffer.

Exceptions

WARN	MSG_SEND_ABORT_BY_RECEIVER.

Definition at line 478 of file Socket.cc.

◆ sendData()

void mcs::Socket::sendData ( Serializable * from )

Send a block of data through the socket.

The data must be handled through a Serializable object or a derived class.

Parameters

from	Addrees of a Serializable object used to send data.

Definition at line 637 of file Socket.cc.

◆ set_struct_timeval()

void mcs::Socket::set_struct_timeval	(	unsigned int	millisec,
		struct timeval *	time
	)

static

Fill a "struct timeval" with the given interval.

Parameters

millisec	Interval in milliseconds.
time	Address of a "struct timeval".

Definition at line 782 of file Socket.cc.

◆ socketToHost()

int mcs::Socket::socketToHost ( unsigned short port )

private

Connect to the host.

This method tries to connect to the host specified in the constructor, to the port specified as parameter.

Note: The timeout interval to connect to a remote host is not the one you specified in the constructor, but is set by the operating system.

Parameters

port	Port to connect to.

Returns: C socket file descriptor.

Exceptions

FATAL MSG_CANT_CONNECT_TO_HOST.

Definition at line 332 of file Socket.cc.

◆ write()

unsigned int mcs::Socket::write	(	void *	buf,
		unsigned int	count
	)

Reads data from a buffer and write in the socket.

This will read count bytes from the buffer pointed by buf and write in the socket. It checks socket availability with chkSend().

Parameters

buf	Buffer from which read data to send;
count	Number of bytes to read from the buffer.

Returns: Number of bytes actually written in the socket.

Exceptions

FATAL MSG_CALLING_SEND

Definition at line 588 of file Socket.cc.

Member Data Documentation

◆ fds

fd_set mcs::Socket::fds

private

Set of socket file descriptors, used with select().

Definition at line 1671 of file mcs.hh.

◆ port

unsigned short int mcs::Socket::port

private

Port on which this socket will connect.

Definition at line 1687 of file mcs.hh.

◆ readto

struct timeval mcs::Socket::readto

private

Timeout interval for read operations.

Definition at line 1693 of file mcs.hh.

◆ sockfd

int mcs::Socket::sockfd

private

C socket file descriptor.

Definition at line 1668 of file mcs.hh.

◆ use_ssl

bool mcs::Socket::use_ssl

private

True if the connection should be encrypted.

Definition at line 1690 of file mcs.hh.

◆ writeto

struct timeval mcs::Socket::writeto

private

Timeout interval fro write operations.

Definition at line 1696 of file mcs.hh.

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

Public Member Functions

Static Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Socket() [1/3]

◆ Socket() [2/3]

◆ Socket() [3/3]

◆ ~Socket()

Member Function Documentation

◆ chkRecv()

◆ chkSend()

◆ Close()

◆ getline()

◆ operator=()

◆ print()

◆ read()

◆ recvChunk() [1/2]

◆ recvChunk() [2/2]

◆ recvData() [1/4]

◆ recvData() [2/4]

◆ recvData() [3/4]

◆ recvData() [4/4]

◆ sendChunk()

◆ sendData()

◆ set_struct_timeval()

◆ socketToHost()

◆ write()

Member Data Documentation

◆ fds

◆ port

◆ readto

◆ sockfd

◆ use_ssl

◆ writeto