A Telnet connection manager, wrapping libtelnet. More...

#include <telnetConn.hpp>

Collaboration diagram for MagAOX::tty::telnetConn:

Public Member Functions
	~telnetConn ()
	D'tor, conducts connection cleanup. More...

int	connect (const std::string &host, const std::string &port)
	Connect to the device. More...

int	login (const std::string &username, const std::string &password)
	Manage the login process on this device. More...

int	noLogin ()
	Set flags as if we're logged in, used when device doesn't require it. More...

int	write (const std::string &buffWrite, int timeoutWrite)
	Write to a telnet connection. More...

int	read (const std::string &eot, int timeoutRead, bool clear=true)
	Read from a telnet connection, until end-of-transmission string is read. More...

int	read (int timeoutRead, bool clear=true)
	Read from a telnet connection, until m_prompt is read. More...

int	writeRead (const std::string &strWrite, bool swallowEcho, int timeoutWrite, int timeoutRead)
	Write to a telnet connection, then get the reply. More...

Static Public Member Functions
static int	send (int sock, const char *buffer, size_t size)
	Internal send for use by event_handler. More...

static void	event_handler (telnet_t telnet, telnet_event_t ev, void *user_data)
	Event handler callback for libtelnet processing. More...

Public Attributes
int	m_sock {0}
	The socket file descriptor. More...

telnet_t *	m_telnet {nullptr}
	libtelnet telnet_t structure More...

std::string	m_usernamePrompt {"Username:"}
	The device's username entry prompt, used for managing login. More...

std::string	m_passwordPrompt {"Password:"}
	The device's password entry prompt, used for managing login. More...

std::string	m_prompt {"$> "}
	The device's prompt, used for detecting end of transmission. More...

int	m_loggedin {0}
	Flag denoting the login state. More...

int	m_EHError {0}
	Used to indicate an error occurred in the event handler callback. More...

std::string	m_strRead
	The accumulated string read from the device. More...

Detailed Description

A Telnet connection manager, wrapping libtelnet.

Establishes the connection to the server, and initializes the libtelnet structure, including registering the event handler callback.

Errors encountered during telnet event handling are indicated by an internal flag, which must be checked each time a libtelnet function is called. If it is nonzero an error has occurred.

Responses from the server are accumulated in the m_strRead member. It is typically cleared before reading, but this can be suppressed when desired.

Because of the way event handling is managed, and the class-global error and response accumulation this is not thread-safe. Any calls to this class methods should be mutex-ed.

Definition at line 80 of file telnetConn.hpp.

Constructor & Destructor Documentation

◆ ~telnetConn()

MagAOX::tty::telnetConn::~telnetConn ( )

D'tor, conducts connection cleanup.

Definition at line 24 of file telnetConn.cpp.

Member Function Documentation

◆ connect()

int MagAOX::tty::telnetConn::connect	(	const std::string &	host,
		const std::string &	port
	)

Connect to the device.

Parameters

[in]	host	The host specification (i.p. address)
[in]	port	the port on the host.

Definition at line 31 of file telnetConn.cpp.

Referenced by MagAOX::app::picoMotorCtrl::appLogic(), MagAOX::app::siglentSDG::appLogic(), and MagAOX::app::trippLitePDU::devConnect().

◆ event_handler()

void MagAOX::tty::telnetConn::event_handler	(	telnet_t *	telnet,
		telnet_event_t *	ev,
		void *	user_data
	)

static

Event handler callback for libtelnet processing.

Resets the internal m_EHError value to TTY_E_NOERROR on entry. Will set it to an error flag if an error is encountered, so this flag should be checked after any call to a libtelnet function.

Warning: this makes telnetConn not thread safe

Definition at line 378 of file telnetConn.cpp.

Referenced by connect().

◆ login()

int MagAOX::tty::telnetConn::login	(	const std::string &	username,
		const std::string &	password
	)

Manage the login process on this device.

Parameters

[in] password The username [in] The password.

Definition at line 90 of file telnetConn.cpp.

Referenced by MagAOX::app::trippLitePDU::devLogin().

◆ noLogin()

int MagAOX::tty::telnetConn::noLogin ( )

Set flags as if we're logged in, used when device doesn't require it.

Definition at line 176 of file telnetConn.cpp.

Referenced by MagAOX::app::picoMotorCtrl::appLogic(), and MagAOX::app::siglentSDG::appLogic().

◆ read() [1/2]

int MagAOX::tty::telnetConn::read	(	const std::string &	eot,
		int	timeoutRead,
		bool	clear = `true`
	)

Read from a telnet connection, until end-of-transmission string is read.

Returns: TTY_E_NOERROR on success; TTY_E_TIMEOUTONREADPOLL if the poll times out.; TTY_E_ERRORONREADPOLL if an error is returned by poll.; TTY_E_TIMEOUTONREAD if a timeout occurs during the read.; TTY_E_ERRORONREAD if an error occurs reading from the file.

Parameters

[in]	eot	the end-of-transmission indicator
[in]	timeoutRead	The timeout in milliseconds.
[in]	clear	[optional] whether or not to clear the strRead buffer

Definition at line 223 of file telnetConn.cpp.

Referenced by MagAOX::app::picoMotorCtrl::appLogic(), MagAOX::app::siglentSDG::appLogic(), MagAOX::app::trippLitePDU::devStatus(), read(), MagAOX::app::siglentSDG::writeCommand(), writeRead(), and MagAOX::app::siglentSDG::writeRead().

◆ read() [2/2]

int MagAOX::tty::telnetConn::read	(	int	timeoutRead,
		bool	clear = `true`
	)

Read from a telnet connection, until m_prompt is read.

Returns: TTY_E_NOERROR on success; TTY_E_TIMEOUTONREADPOLL if the poll times out.; TTY_E_ERRORONREADPOLL if an error is returned by poll.; TTY_E_TIMEOUTONREAD if a timeout occurs during the read.; TTY_E_ERRORONREAD if an error occurs reading from the file.

Parameters

[in]	timeoutRead	The timeout in milliseconds.
[in]	clear	[optional] whether or not to clear the strRead buffer

Definition at line 287 of file telnetConn.cpp.

◆ send()

int MagAOX::tty::telnetConn::send	(	int	sock,
		const char *	buffer,
		size_t	size
	)

static

Internal send for use by event_handler.

Definition at line 353 of file telnetConn.cpp.

Referenced by event_handler().

◆ write()

int MagAOX::tty::telnetConn::write	(	const std::string &	buffWrite,
		int	timeoutWrite
	)

Write to a telnet connection.

Returns: TTY_E_NOERROR on success; TTY_E_TIMEOUTONWRITEPOLL if the poll times out.; TTY_E_ERRORONWRITEPOLL if an error is returned by poll.; TTY_E_TIMEOUTONWRITE if a timeout occurs during the write.; TTY_E_ERRORONWRITE if an error occurs writing to the file.

Parameters

[in]	buffWrite	The characters to write to the telnet.
[in]	timeoutWrite	The timeout in milliseconds.

Definition at line 182 of file telnetConn.cpp.

Referenced by MagAOX::app::picoMotorCtrl::appLogic(), MagAOX::app::siglentSDG::appLogic(), MagAOX::app::picoMotorCtrl::channelThreadExec(), login(), MagAOX::app::siglentSDG::writeCommand(), writeRead(), and MagAOX::app::siglentSDG::writeRead().

◆ writeRead()

int MagAOX::tty::telnetConn::writeRead	(	const std::string &	strWrite,
		bool	swallowEcho,
		int	timeoutWrite,
		int	timeoutRead
	)

Write to a telnet connection, then get the reply.

The read is conducted until the m_prompt string is received. Echo characters are swallowed if desired.

Returns: TTY_E_NOERROR on success; TTY_E_TIMEOUTONWRITEPOLL if the poll times out.; TTY_E_ERRORONWRITEPOLL if an error is returned by poll.; TTY_E_TIMEOUTONWRITE if a timeout occurs during the write.; TTY_E_ERRORONWRITE if an error occurs writing to the file.; TTY_E_TIMEOUTONREADPOLL if the poll times out.; TTY_E_ERRORONREADPOLL if an error is returned by poll.; TTY_E_TIMEOUTONREAD if a timeout occurs during the read.; TTY_E_ERRORONREAD if an error occurs reading from the file.

Parameters

[in]	strWrite	The characters to write to the telnet.
[in]	swallowEcho	If true, strWrite.size() characters are read after the write
[in]	timeoutWrite	The write timeout in milliseconds.
[in]	timeoutRead	The read timeout in milliseconds.

Definition at line 294 of file telnetConn.cpp.

Referenced by MagAOX::app::trippLitePDU::devPostLogin(), MagAOX::app::trippLitePDU::devStatus(), MagAOX::app::trippLitePDU::turnOutletOff(), MagAOX::app::trippLitePDU::turnOutletOn(), and MagAOX::app::siglentSDG::writeRead().

Member Data Documentation

◆ m_EHError

int MagAOX::tty::telnetConn::m_EHError {0}

Used to indicate an error occurred in the event handler callback.

Definition at line 107 of file telnetConn.hpp.

Referenced by event_handler(), login(), read(), and writeRead().

◆ m_loggedin

int MagAOX::tty::telnetConn::m_loggedin {0}

Flag denoting the login state.

Used to manage different behaviors in the libtelnet event handler.

TELNET_WAITING_USER: waiting on m_usernamePrompt
TELNET_GOT_USER: got m_usernamePrompt
TELNET_WAITING_PASS: waiting on m_passwordPrompt
TELNET_GOT_PASS: got m_passwordPrompt
TELNET_WAITING_PROMPT: waiting on m_prompt
TELNET_LOGGED_IN: logged in

Definition at line 104 of file telnetConn.hpp.

Referenced by connect(), event_handler(), login(), and noLogin().

◆ m_passwordPrompt

std::string MagAOX::tty::telnetConn::m_passwordPrompt {"Password:"}

The device's password entry prompt, used for managing login.

Definition at line 90 of file telnetConn.hpp.

Referenced by event_handler().

◆ m_prompt

std::string MagAOX::tty::telnetConn::m_prompt {"$> "}

The device's prompt, used for detecting end of transmission.

Definition at line 92 of file telnetConn.hpp.

Referenced by MagAOX::app::picoMotorCtrl::picoMotorCtrl(), MagAOX::app::siglentSDG::siglentSDG(), MagAOX::app::trippLitePDU::devLogin(), MagAOX::app::trippLitePDU::devPostLogin(), event_handler(), read(), and writeRead().

◆ m_sock

int MagAOX::tty::telnetConn::m_sock {0}

The socket file descriptor.

Definition at line 82 of file telnetConn.hpp.

Referenced by ~telnetConn(), connect(), event_handler(), login(), read(), write(), and writeRead().

◆ m_strRead

std::string MagAOX::tty::telnetConn::m_strRead

The accumulated string read from the device.

This needs to be clear()-ed when expecting a new response to start.

Warning: This makes telnetConn NOT threadsafe.

Definition at line 113 of file telnetConn.hpp.

Referenced by MagAOX::app::picoMotorCtrl::appLogic(), MagAOX::app::siglentSDG::appLogic(), MagAOX::app::trippLitePDU::devStatus(), event_handler(), read(), writeRead(), and MagAOX::app::siglentSDG::writeRead().

◆ m_telnet

telnet_t* MagAOX::tty::telnetConn::m_telnet {nullptr}

libtelnet telnet_t structure

Definition at line 84 of file telnetConn.hpp.

Referenced by ~telnetConn(), connect(), login(), read(), write(), and writeRead().

◆ m_usernamePrompt

std::string MagAOX::tty::telnetConn::m_usernamePrompt {"Username:"}

The device's username entry prompt, used for managing login.

Definition at line 87 of file telnetConn.hpp.

Referenced by MagAOX::app::trippLitePDU::devLogin(), and event_handler().

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

libMagAOX/tty/telnetConn.hpp
libMagAOX/tty/telnetConn.cpp

Public Member Functions

Static Public Member Functions

Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ ~telnetConn()

Member Function Documentation

◆ connect()

◆ event_handler()

◆ login()

◆ noLogin()

◆ read() [1/2]

◆ read() [2/2]

◆ send()

◆ write()

◆ writeRead()

Member Data Documentation

◆ m_EHError

◆ m_loggedin

◆ m_passwordPrompt

◆ m_prompt

◆ m_sock

◆ m_strRead

◆ m_telnet

◆ m_usernamePrompt