iox::posix::UnixDomainSocket

Wrapper class for unix domain socket.

#include <unix_domain_socket.hpp>

Inherits from DesignPattern::Creation< UnixDomainSocket, IpcChannelError >

Public Classes

	Name
struct	NoPathPrefix_t

Public Types

	Name
using cxx::string< LONGEST_VALID_NAME >	UdsName_t

Public Functions

	Name
	UnixDomainSocket() default constructor. The result is an invalid UnixDomainSocket object which can be reassigned later by using the move constructor.
	UnixDomainSocket(const UnixDomainSocket & other)
	UnixDomainSocket(UnixDomainSocket && other)
UnixDomainSocket &	operator=(const UnixDomainSocket & other)
UnixDomainSocket &	operator=(UnixDomainSocket && other)
	~UnixDomainSocket()
cxx::expected< IpcChannelError >	destroy() close the unix domain socket.
cxx::expected< IpcChannelError >	send(const std::string & msg) const send a message using std::string.
cxx::expected< IpcChannelError >	timedSend(const std::string & msg, const units::Duration & timeout) const try to send a message for a given timeout duration using std::string
cxx::expected< std::string, IpcChannelError >	receive() const receive message using std::string.
cxx::expected< std::string, IpcChannelError >	timedReceive(const units::Duration & timeout) const try to receive message for a given timeout duration using std::string.
cxx::expected< bool, IpcChannelError >	isOutdated() checks whether the unix domain socket is outdated
cxx::expected< bool, IpcChannelError >	unlinkIfExists(const UdsName_t & name) unlink the provided unix domain socket
cxx::expected< bool, IpcChannelError >	unlinkIfExists(const NoPathPrefix_t, const UdsName_t & name) unlink the provided unix domain socket

Public Attributes

	Name
constexpr NoPathPrefix_t	NoPathPrefix
constexpr char	PATH_PREFIX
constexpr size_t	MAX_MESSAGE_SIZE Max message size is on linux = 4096 and on mac os = 2048. To have the same behavior on every platform we use 2048.
constexpr size_t	SHORTEST_VALID_NAME
constexpr size_t	NULL_TERMINATOR_SIZE
constexpr size_t	LONGEST_VALID_NAME The name length is limited by the size of the sockaddr_un::sun_path buffer and the path prefix.
constexpr int32_t	ERROR_CODE
constexpr int32_t	INVALID_FD

Friends

	Name
class	DesignPattern::Creation< UnixDomainSocket, IpcChannelError > for calling private constructor in create method

Additional inherited members

Public Types inherited from DesignPattern::Creation< UnixDomainSocket, IpcChannelError >

	Name
using Creation< DerivedClass, ErrorType >	CreationPattern_t
using iox::cxx::expected< DerivedClass, ErrorType >	result_t
using ErrorType	errorType_t

Public Functions inherited from DesignPattern::Creation< UnixDomainSocket, IpcChannelError >

	Name
template \<typename... Targs> result_t	create(Targs &&... args) factory method which guarantees that either a working object is produced or an error value describing the error during construction
result_t	verify(DerivedClass && newObject) verifies if a class was created successfully
template \<typename... Targs> iox::cxx::expected< ErrorType >	placementCreate(void *const memory, Targs &&... args) factory method which guarantees that either a working object is produced or an error value describing the error during construction
	Creation() =default
	Creation(Creation && rhs)
	Creation(const Creation & rhs) =default
bool	isInitialized() const returns true if the object was constructed successfully, otherwise false

Protected Attributes inherited from DesignPattern::Creation< UnixDomainSocket, IpcChannelError >

	Name
bool	m_isInitialized
ErrorType	m_errorValue

Public Types Documentation

using UdsName_t

using iox::posix::UnixDomainSocket::UdsName_t =  cxx::string<LONGEST_VALID_NAME>;

Public Functions Documentation

function UnixDomainSocket

UnixDomainSocket()

default constructor. The result is an invalid UnixDomainSocket object which can be reassigned later by using the move constructor.

function UnixDomainSocket

UnixDomainSocket(
    const UnixDomainSocket & other
)

function UnixDomainSocket

UnixDomainSocket(
    UnixDomainSocket && other
)

function operator=

UnixDomainSocket & operator=(
    const UnixDomainSocket & other
)

function operator=

UnixDomainSocket & operator=(
    UnixDomainSocket && other
)

function ~UnixDomainSocket

~UnixDomainSocket()

function destroy

cxx::expected< IpcChannelError > destroy()

close the unix domain socket.

function send

cxx::expected< IpcChannelError > send(
    const std::string & msg
) const

send a message using std::string.

Parameters:

• msg to send

Return: IpcChannelError if error occured

function timedSend

cxx::expected< IpcChannelError > timedSend(
    const std::string & msg,
    const units::Duration & timeout
) const

try to send a message for a given timeout duration using std::string

Parameters:

• msg to send
• timout for the send operation

Return: IpcChannelError if error occured

function receive

cxx::expected< std::string, IpcChannelError > receive() const

receive message using std::string.

Return: received message. In case of an error, IpcChannelError is returned and msg is empty.

function timedReceive

cxx::expected< std::string, IpcChannelError > timedReceive(
    const units::Duration & timeout
) const

try to receive message for a given timeout duration using std::string.

Parameters:

• timout for the receive operation

Return: received message. In case of an error, IpcChannelError is returned and msg is empty.

function isOutdated

cxx::expected< bool, IpcChannelError > isOutdated()

checks whether the unix domain socket is outdated

Return: true if the unix domain socket is outdated, false otherwise, IpcChannelError if error occured

function unlinkIfExists

static cxx::expected< bool, IpcChannelError > unlinkIfExists(
    const UdsName_t & name
)

unlink the provided unix domain socket

Parameters:

• name of the unix domain socket to unlink

Return: true if the unix domain socket could be unlinked, false otherwise, IpcChannelError if error occured

function unlinkIfExists

static cxx::expected< bool, IpcChannelError > unlinkIfExists(
    const NoPathPrefix_t,
    const UdsName_t & name
)

unlink the provided unix domain socket

Parameters:

• NoPathPrefix signalling that this method does not add a path prefix
• name of the unix domain socket to unlink

Return: true if the unix domain socket could be unlinked, false otherwise, IpcChannelError if error occured

Public Attributes Documentation

variable NoPathPrefix

static constexpr NoPathPrefix_t NoPathPrefix {};

variable PATH_PREFIX

static constexpr char PATH_PREFIX = "/tmp/";

variable MAX_MESSAGE_SIZE

static constexpr size_t MAX_MESSAGE_SIZE = 2048U;

Max message size is on linux = 4096 and on mac os = 2048. To have the same behavior on every platform we use 2048.

variable SHORTEST_VALID_NAME

static constexpr size_t SHORTEST_VALID_NAME = 2U;

variable NULL_TERMINATOR_SIZE

static constexpr size_t NULL_TERMINATOR_SIZE = 1;

variable LONGEST_VALID_NAME

static constexpr size_t LONGEST_VALID_NAME = sizeof(sockaddr_un::sun_path) - 1;

The name length is limited by the size of the sockaddr_un::sun_path buffer and the path prefix.

variable ERROR_CODE

static constexpr int32_t ERROR_CODE = -1;

variable INVALID_FD

static constexpr int32_t INVALID_FD = -1;

Friends

friend DesignPattern::Creation< UnixDomainSocket, IpcChannelError >

friend class DesignPattern::Creation< UnixDomainSocket, IpcChannelError >;

for calling private constructor in create method

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Updated on 31 May 2022 at 15:29:15 CEST