comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts > Class Template Reference

#include "comms/GenericMessage.h"

Detailed Description

template<typename TMessage, typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>
class comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >

Generic Message.

Generic message is there to substitute definition of actual message when contents of the latter are not important. It defines single data field as variable length sequence of raw bytes (see GenericMessageFields). The GenericMessage can be useful when implementing some kind of "bridge" or "firewall", that requires knowledge only about message ID and doesn't care much about message contents. The comms::protocol::MsgIdLayer support creation of the GenericMessage in case the received message ID is not known (supported by using comms::option::app::SupportGenericMessage option).

Template Parameters

TMessage	Common message interface class, becomes one of the base classes.
TFieldOpts	Extra option(s) (multiple options need to be bundled in std::tuple) to be passed to the definition of the data field (see GenericMessageFields).
TExtraOpts	Extra option(s) (multple options need to be bundled in std::tuple) to be passed to comms::MessageBase which is base to this one.

Precondition

Requires the common message interface (TMessage) to define inner MsgIdType and MsgIdParamType types (expected to use comms::option::def::MsgIdType, see Using Generic Message)

Inheritance diagram for comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >:

Public Types
using	AllFields = FieldsProvidedWithOption
	All field classes provided with comms::option::def::FieldsImpl option.
using	DispatchRetType = typename Handler::RetType
	Return type of the dispatch() member function.
using	Endian = typename BaseImpl::Endian
	Serialisation endian type.
using	Field = BaseImpl::Field
	Type of default base class for all the fields.
using	Handler = TypeProvidedWithOption
	Type of the message handler object.
using	ImplOptions = details::MessageImplOptionsParser< TOptions... >
	All the options provided to this class bundled into struct.
using	InterfaceOptions = details::MessageInterfaceOptionsParser< TOptions... >
	All the options bundled into struct.
using	MsgIdParamType = typename Base::MsgIdParamType
	Type of the message ID passed as parameter.
using	MsgIdType = typename Base::MsgIdType
	Type of the message ID.
using	MsgType = typename ImplOptions::MsgType
	Type of the actual message provided via comms::option::def::MsgType.
using	ReadIterator = TypeProvidedWithOption
	Type of the iterator used for reading message contents from sequence of bytes stored somewhere.
using	TransportFields = FieldsProvidedWithOption
	std::tuple of extra fields from transport layers that may affect the way the message fields get serialized / deserialized.
using	VersionType = typename BaseImpl::VersionType
	Type used for version info.
using	WriteIterator = TypeProvidedWithOption
	Type of the iterator used for writing message contents into sequence of bytes stored somewhere.

Public Member Functions
	GenericMessage ()=delete
	Default constructor is deleted.
	GenericMessage (const GenericMessage &)=default
	Copy constructor.
	GenericMessage (GenericMessage &&)=default
	Move constructor.
	GenericMessage (MsgIdParamType id)
	Constructor.
	~GenericMessage () noexcept=default
	Destructor.
	COMMS_MSG_FIELDS_NAMES (data)
	Allow access to internal fields.
DispatchRetType	dispatch (Handler &handler)
	Dispatch message to the handler for processing.
bool	doFieldsVersionUpdate ()
	Update version information of all the fields.
MsgIdParamType	doGetId () const
	Get message ID information.
std::size_t	doLength () const
	Default implementation of length calculation functionality.
template<std::size_t TFromIdx>
std::size_t	doLengthFrom () const
	Default implementation of partial length calculation functionality.
template<std::size_t TFromIdx, std::size_t TUntilIdx>
std::size_t	doLengthFromUntil () const
	Default implementation of partial length calculation functionality.
template<std::size_t TUntilIdx>
std::size_t	doLengthUntil () const
	Default implementation of partial length calculation functionality.
template<std::size_t TFromIdx, std::size_t TUntilIdx>
std::size_t	doMaxLengthFromUntil () const
	Compile time constant of maximal partial serialisation length.
template<std::size_t TFromIdx, std::size_t TUntilIdx>
std::size_t	doMinLengthFromUntil () const
	Compile time constant of minimal partial serialisation length.
template<typename TIter >
ErrorStatus	doRead (TIter &iter, std::size_t size)
	Default implementation of read functionality.
bool	doRefresh () const
	Default implementation of refreshing functionality.
bool	doValid () const
	Default implementation of validity check functionality.
template<typename TIter >
ErrorStatus	doWrite (TIter &iter, std::size_t size) const
	Default implementation of write functionality.
AllFields &	fields ()
	Get an access to the fields of the message.
const AllFields &	fields () const
	Get an access to the fields of the message.
MsgIdParamType	getId () const
	Retrieve ID of the message.
std::size_t	length () const
	Get number of bytes required to serialise this message.
const char *	name () const
	Get name of the message.
GenericMessage &	operator= (const GenericMessage &)=default
	Copy assignment.
GenericMessage &	operator= (GenericMessage &&)=default
	Move assignment.
ErrorStatus	read (ReadIterator &iter, std::size_t size)
	Read message contents using provided iterator.
bool	refresh ()
	Refresh to contents of the message.
TransportFields &	transportFields ()
	Get access to extra transport fields.
const TransportFields &	transportFields () const
	Const version of transportFields.
bool	valid () const
	Check validity of message contents.
VersionType &	version ()
	Access to version information.
const VersionType &	version () const
	Const access to version information.
ErrorStatus	write (WriteIterator &iter, std::size_t size) const
	Write message contents using provided iterator.

Static Public Member Functions
static constexpr bool	areFieldsVersionDependent ()
	Compile time check of whether the message fields are version dependent.
static constexpr MsgIdParamType	doGetId ()
	Default implementation of ID retrieval functionality.
static constexpr std::size_t	doMaxLength ()
	Compile time constant of maximal serialisation length.
template<std::size_t TFromIdx>
static constexpr std::size_t	doMaxLengthFrom ()
	Compile time constant of maximal partial serialisation length.
template<std::size_t TUntilIdx>
static constexpr std::size_t	doMaxLengthUntil ()
	Compile time constant of maximal partial serialisation length.
static constexpr std::size_t	doMinLength ()
	Compile time constant of minimal serialisation length.
template<std::size_t TFromIdx>
static constexpr std::size_t	doMinLengthFrom ()
	Compile time constant of minimal partial serialisation length.
template<std::size_t TUntilIdx>
static constexpr std::size_t	doMinLengthUntil ()
	Compile time constant of minimal partial serialisation length.
static const char *	doName ()
	Get message name information.
static constexpr bool	hasCustomName ()
	Compile time inquiry of whether comms::MessageBase has notified about custom name retrieval function in the derived class via comms::option::def::HasName.
static constexpr bool	hasCustomRefresh ()
	Compile time inquiry of whether comms::MessageBase has notified about custom refresh functionality in the derived class via comms::option::def::HasCustomRefresh.
static constexpr bool	hasDispatch ()
	Compile type inquiry whether message interface class defines dispatch() and dispatchImpl() member functions as well as Handler and DispatchRetType types.
static constexpr bool	hasEndian ()
	Compile type inquiry whether message interface class defines Endian and Field types.
static constexpr bool	hasFailOnInvalid ()
	Compile time inquiry of whether fail on invalid has been requested comms::option::def::FailOnInvalid option.
static constexpr bool	hasFields ()
	Compile type inquiry whether fields have been provided via comms::option::def::FieldsImpl.
static constexpr bool	hasGetId ()
	Compile type inquiry whether message interface class defines getId() and getIdImpl() member functions.
static constexpr bool	hasLength ()
	Compile type inquiry whether message interface class defines length() and lengthImpl() member functions.
static constexpr bool	hasMsgIdType ()
	Compile type inquiry whether message interface class defines MsgIdType and MsgIdParamType types.
static constexpr bool	hasMsgType ()
	Compile time inquiry of whether the actual message type has been provided via comms::option::def::MsgType.
static constexpr bool	hasName ()
	Compile type inquiry whether message interface class defines name() and nameImpl() member functions.
static constexpr bool	hasPolymorphicDispatch ()
	Compile time inquiry of whether polymoriphic dispatch has been requested via interface options and hasn't been inhibited by the comms::option::app::NoDispatchImpl.
static constexpr bool	hasPolymorphicLength ()
	Compile time inquiry of whether polymoriphic length has been requested via interface options and hasn't been inhibited by the comms::option::app::NoLengthImpl.
static constexpr bool	hasPolymorphicRead ()
	Compile time inquiry of whether polymoriphic read has been requested via interface options and hasn't been inhibited by the comms::option::app::NoReadImpl.
static constexpr bool	hasPolymorphicValid ()
	Compile time inquiry of whether polymoriphic validity check has been requested via interface options and hasn't been inhibited by the comms::option::app::NoValidImpl.
static constexpr bool	hasPolymorphicWrite ()
	Compile time inquiry of whether polymoriphic write has been requested via interface options and hasn't been inhibited by the comms::option::app::NoWriteImpl.
static constexpr bool	hasRead ()
	Compile type inquiry whether message interface class defines read() and readImpl() member functions as well as ReadIterator type.
static constexpr bool	hasRefresh ()
	Compile type inquiry whether message interface class defines refresh() and refreshImpl() member functions.
static constexpr bool	hasStaticMsgId ()
	Compile type inquiry whether static numeric id has been provided via comms::option::def::StaticNumIdImpl.
static constexpr bool	hasTransportFields ()
	Compile type inquiry whether message interface class defines transportFields() member functions as well as TransportFields type.
static constexpr bool	hasValid ()
	Compile type inquiry whether message interface class defines valid() and validImpl() member functions.
static constexpr bool	hasVersionInTransportFields ()
	Compile type inquiry whether there is version information inside transport fields.
static constexpr bool	hasWrite ()
	Compile type inquiry whether message interface class defines write() and writeImpl() member functions as well as WriteIterator type.
static constexpr std::intmax_t	staticMsgId ()
	Compile time retrieval of the message id provided via comms::option::def::StaticNumIdImpl.
static constexpr std::size_t	versionIdxInTransportFields ()
	Compile type inquiry of version field index in transport field.

Protected Member Functions
virtual DispatchRetType	dispatchImpl (Handler &handler) override
	Implementation of dispatch functionality.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doReadFrom (TIter &iter, std::size_t len)
	Helper function that allows to read only limited number of fields.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doReadFromAndUpdateLen (TIter &iter, std::size_t &len)
	Same as doReadFrom(), but modifies length parameter.
template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >
ErrorStatus	doReadFromUntil (TIter &iter, std::size_t len)
	Helper function that allows to read only limited number of fields.
template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >
ErrorStatus	doReadFromUntilAndUpdateLen (TIter &iter, std::size_t &len)
	Same as doReadFromUntil(), but modifies length parameter.
template<std::size_t TIdx, typename TIter >
void	doReadNoStatusFrom (TIter &iter)
	Helper function that allows to read only limited number of fields.
template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >
void	doReadNoStatusFromUntil (TIter &iter)
	Helper function that allows to read only limited number of fields.
template<std::size_t TIdx, typename TIter >
void	doReadNoStatusUntil (TIter &iter)
	Helper function that allows to read only limited number of fields.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doReadUntil (TIter &iter, std::size_t &len)
	Helper function that allows to read only limited number of fields.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doReadUntilAndUpdateLen (TIter &iter, std::size_t &len)
	Same as doReadUntil(), but updating length parameter.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doWriteFrom (TIter &iter, std::size_t len) const
	Helper function that allows to write only limited number of fields.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doWriteFromAndUpdateLen (TIter &iter, std::size_t &len) const
	Same as doWriteFrom(), but modifies length parameter.
template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >
ErrorStatus	doWriteFromUntil (TIter &iter, std::size_t len) const
	Helper function that allows to write only limited number of fields.
template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >
ErrorStatus	doWriteFromUntilAndUpdateLen (TIter &iter, std::size_t &len) const
	Same as doWriteNoStatusFrom(), but updates length information.
template<std::size_t TIdx, typename TIter >
void	doWriteNoStatusFrom (TIter &iter) const
	Helper function that allows to write only limited number of fields.
template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >
void	doWriteNoStatusFromUntil (TIter &iter) const
	Helper function that allows to write only limited number of fields.
template<std::size_t TIdx, typename TIter >
void	doWriteNoStatusUntil (TIter &iter) const
	Helper function that allows to write only limited number of fields.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doWriteUntil (TIter &iter, std::size_t len) const
	Helper function that allows to write only limited number of fields.
template<std::size_t TIdx, typename TIter >
ErrorStatus	doWriteUntilAndUpdateLen (TIter &iter, std::size_t &len) const
	Same as doWriteUntil(), but modifies length parameter.
virtual MsgIdParamType	getIdImpl () const override
	Implementation of ID retrieval functionality.
virtual std::size_t	lengthImpl () const override
	Implementation of polymorphic length calculation functionality.
virtual const char *	nameImpl () const override
	Implementation of polymorphic name retrieval functionality.
virtual ErrorStatus	readImpl (ReadIterator &iter, std::size_t size) override
	Implementation of polymorphic read functionality.
virtual bool	refreshImpl () override
	Implementation of polymorphic refresh functionality.
virtual bool	validImpl () const override
	Implementation of polymorphic validity check functionality.
virtual ErrorStatus	writeImpl (WriteIterator &iter, std::size_t size) const override
	Implementation of polymorphic write functionality.

Static Protected Member Functions
template<typename T , typename TIter >
static T	readData (TIter &iter)
	Read data from input area.
template<typename T , std::size_t TSize, typename TIter >
static T	readData (TIter &iter)
	Read partial data from input area.
template<typename T , typename TIter >
static void	writeData (T value, TIter &iter)
	Write data into the output area.
template<std::size_t TSize, typename T , typename TIter >
static void	writeData (T value, TIter &iter)
	Write partial data into the output area.

Related Symbols
(Note that these are not member symbols.)
#define	COMMS_MSG_FIELD_ALIAS(f_, ...)
	Generate convinience alias types and access member functions for other member fields.
#define	COMMS_MSG_FIELD_ALIAS_ACCESS(f_, ...)   COMMS_DO_ALIAS(field_, f_, __VA_ARGS__)
	Generate convinience alias access member functions for other member fields.
#define	COMMS_MSG_FIELDS_ACCESS(...)
	Add convenience access enum and functions to message fields.
#define	COMMS_MSG_FIELDS_NAMES(...)
	Provide names for message fields.
#define	COMMS_MSG_TRANSPORT_FIELD_ALIAS(f_, ...)
	Generate convinience alias access member functions for extra member transport fields.
#define	COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS(f_, ...)   COMMS_EXPAND(COMMS_DO_ALIAS(transportField_, f_, __VA_ARGS__))
	Generate convinience alias access member functions for extra member transport fields.
#define	COMMS_MSG_TRANSPORT_FIELDS_ACCESS(...)
	Add convenience access enum and functions to extra transport fields.
#define	COMMS_MSG_TRANSPORT_FIELDS_NAMES(...)
	Provide names for extra transport fields.
template<typename TMessage1 , typename TMessage2 , typename... TOptions>
bool	operator!= (const MessageBase< TMessage1, TOptions... > &msg1, const MessageBase< TMessage2, TOptions... > &msg2) noexcept
	Message object inequality comparison operator.
template<typename TMessage1 , typename TMessage2 , typename... TOptions>
bool	operator== (const MessageBase< TMessage1, TOptions... > &msg1, const MessageBase< TMessage2, TOptions... > &msg2) noexcept
	Message object equality comparison operator.

Member Typedef Documentation

AllFields

template<typename TMessage , typename... TOptions>

using comms::MessageBase< TMessage, TOptions >::AllFields = FieldsProvidedWithOption

inherited

All field classes provided with comms::option::def::FieldsImpl option.

The type is not defined if comms::option::def::FieldsImpl option wasn't provided to comms::MessageBase.

DispatchRetType

template<typename... TOptions>

using comms::Message< TOptions >::DispatchRetType = typename Handler::RetType

inherited

Return type of the dispatch() member function.

Equal to Handler::RetType if such exists, void otherwise.

Endian

template<typename... TOptions>

using comms::Message< TOptions >::Endian = typename BaseImpl::Endian

inherited

Serialisation endian type.

The type exists only if comms::option::def::BigEndian or comms::option::def::LittleEndian options were used to specify it.

See also

hasEndian()

Field

template<typename... TOptions>

using comms::Message< TOptions >::Field = BaseImpl::Field

inherited

Type of default base class for all the fields.

Requires definition of the Endian type, i.e. the type exist only if comms::option::def::BigEndian or comms::option::def::LittleEndian options were used.

Handler

template<typename... TOptions>

using comms::Message< TOptions >::Handler = TypeProvidedWithOption

inherited

Type of the message handler object.

The type exists only if comms::option::app::Handler option was provided to comms::Message to specify one.

ImplOptions

template<typename TMessage , typename... TOptions>

using comms::MessageBase< TMessage, TOptions >::ImplOptions = details::MessageImplOptionsParser<TOptions...>

inherited

All the options provided to this class bundled into struct.

For internal use only

InterfaceOptions

template<typename... TOptions>

using comms::Message< TOptions >::InterfaceOptions = details::MessageInterfaceOptionsParser<TOptions...>

inherited

All the options bundled into struct.

For internal use only.

MsgIdParamType

template<typename TMessage , typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>

using comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >::MsgIdParamType = typename Base::MsgIdParamType

Type of the message ID passed as parameter.

The same as comms::Message::MsgIdParamType;

MsgIdType

template<typename TMessage , typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>

using comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >::MsgIdType = typename Base::MsgIdType

Type of the message ID.

The same as comms::Message::MsgIdType;

MsgType

template<typename TMessage , typename... TOptions>

using comms::MessageBase< TMessage, TOptions >::MsgType = typename ImplOptions::MsgType

inherited

Type of the actual message provided via comms::option::def::MsgType.

If comms::option::def::MsgType hasn't been used equals to void.

ReadIterator

template<typename... TOptions>

using comms::Message< TOptions >::ReadIterator = TypeProvidedWithOption

inherited

Type of the iterator used for reading message contents from sequence of bytes stored somewhere.

The type exists only if comms::option::app::ReadIterator option was provided to comms::Message to specify one.

See also

hasRead()

TransportFields

template<typename... TOptions>

using comms::Message< TOptions >::TransportFields = FieldsProvidedWithOption

inherited

std::tuple of extra fields from transport layers that may affect the way the message fields get serialized / deserialized.

The type exists only if comms::option::def::ExtraTransportFields option has been provided to comms::Message class to specify them.

See also

hasTransportFields()

VersionType

template<typename... TOptions>

using comms::Message< TOptions >::VersionType = typename BaseImpl::VersionType

inherited

Type used for version info.

The type exists only if comms::option::def::VersionInExtraTransportFields option has been provided.

WriteIterator

template<typename... TOptions>

using comms::Message< TOptions >::WriteIterator = TypeProvidedWithOption

inherited

Type of the iterator used for writing message contents into sequence of bytes stored somewhere.

The type exists only if comms::option::app::WriteIterator option was provided to comms::Message to specify one.

See also

hasWrite()

Constructor & Destructor Documentation

GenericMessage()

template<typename TMessage , typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>

comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >::GenericMessage ( MsgIdParamType  id )

explicit

Constructor.

Parameters

[in]

id

ID of the message

Member Function Documentation

areFieldsVersionDependent()

template<typename TMessage , typename... TOptions>

static constexpr bool comms::MessageBase< TMessage, TOptions >::areFieldsVersionDependent ( )

staticconstexprinherited

Compile time check of whether the message fields are version dependent.

The function doesn't exist if comms::option::def::FieldsImpl option wasn't provided to comms::MessageBase.

Returns

true if at least one of the fields is version dependent.

COMMS_MSG_FIELDS_NAMES()

template<typename TMessage , typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>

comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >::COMMS_MSG_FIELDS_NAMES

(

data

)

Allow access to internal fields.

See definition of COMMS_MSG_FIELDS_NAMES() macro related to comms::MessageBase class for details.

dispatch()

template<typename... TOptions>

DispatchRetType comms::Message< TOptions >::dispatch ( Handler &  handler )

inherited

Dispatch message to the handler for processing.

The function exists only if comms::option::app::Handler option was provided to comms::Message to specify type of the handler. The function invokes virtual dispatchImpl() function.

Parameters

handler

Handler object to dispatch message to.

dispatchImpl()

template<typename TMessage , typename... TOptions>

virtual DispatchRetType comms::MessageBase< TMessage, TOptions >::dispatchImpl ( Handler &  handler )

overrideprotectedvirtualinherited

Implementation of dispatch functionality.

This function exists only if the following conditions are true:

• comms::option::app::Handler option option was provided to comms::Message.
• comms::option::def::MsgType option was used to specify actual type of the inheriting message class.
• comms::option::app::NoDispatchImpl option was NOT used.

In order to properly implement the dispatch functionality this class imposes several requirements. First of all, the custom message class must provide its own type as an argument to comms::option::def::MsgType option:

class MyMessageBase :  public comms::Message<...> { ...};
 
class Message1 :
    public comms::MessageBase<
        MyMessageBase,
        ...
        comms::option::def::MsgType<Message1>
        ...
    >
{
    ...
};

Second, The Handler type (inherited from comms::Message) must implement "handle()" member function for every message type (specified as Message1, Message2, ...) it is supposed to handle:

class MyHandler {
public:
    DispatchRetType handle(Message1& msg);
    DispatchRetType handle(Message2& msg);
    ...
}

The "handle()" functions may be virtual. If the handler is capable of handling only limited number of messages, there is a need to provide additional "handle()" member function to implement default handling functionality (usually ignore the message by doing nothing) for all other messages that weren't handled explicitly.

class MyHandler {
public:
    ...
    DispatchRetType handle(MessageBase& msg);
}

Where "MessageBase" is a common base class for all the possible messages.

Once the requirements above are properly implemented, the implementation of this message is very simple:

DispatchRetType dispatchImpl(Handler& handler)
{
    typedef <actual-message-type-provided-with-option> Actual;
    return handler.handle(static_cast<Actual&>(*this));
}

The code above forces a compiler to choose appropriate handle() function in the Handler class, based on the actual type of the message. If such function is not found, the compiler will choose to call the one that covers all possible messages "void handle(MessageBase& msg)".

Parameters

handler

Reference to handler object.

Reimplemented from comms::Message< TOptions >.

doFieldsVersionUpdate()

template<typename TMessage , typename... TOptions>

bool comms::MessageBase< TMessage, TOptions >::doFieldsVersionUpdate ( )

inherited

Update version information of all the fields.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase and comms::option::def::VersionInExtraTransportFields was provided to the message interface class (comms::Message).
This function will invoke such setVersion() member function for every field object listed with comms::option::def::FieldsImpl option and will return true if at least one of the invoked functions returned true (similar to doRefresh()).

Returns

true when at least one of the fields has been updated.

doGetId() [1/2]

template<typename TMessage , typename... TOptions>

static constexpr MsgIdParamType comms::MessageBase< TMessage, TOptions >::doGetId ( )

staticconstexprinherited

Default implementation of ID retrieval functionality.

This function exists only if comms::option::def::StaticNumIdImpl option was provided to comms::MessageBase.

Returns

Numeric ID of the message.

doGetId() [2/2]

template<typename TMessage , typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>

MsgIdParamType comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >::doGetId

(

)

const

Get message ID information.

The comms::MessageBase::getIdImpl() will invoke this function.

doLength()

template<typename TMessage , typename... TOptions>

std::size_t comms::MessageBase< TMessage, TOptions >::doLength ( ) const

inherited

Default implementation of length calculation functionality.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. To make this function works, every field class must provide "length()" function with following signature:

std::size_t length() const;

This function will invoke such "length()" member function for every field object listed with comms::option::def::FieldsImpl option. The final result is a summary of the "length" values of all the fields.

Returns

Serialisation length of the message.

doLengthFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx>

std::size_t comms::MessageBase< TMessage, TOptions >::doLengthFrom ( ) const

inherited

Default implementation of partial length calculation functionality.

Similar to length() member function but starts the calculation at the the field specified using TFromIdx template parameter.

Template Parameters

TFromIdx

Index of the field, from which length calculation will start

Returns

Calculated serialisation length

Precondition

TFromIdx < std::tuple_size<AllFields>::value

doLengthFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx>

std::size_t comms::MessageBase< TMessage, TOptions >::doLengthFromUntil ( ) const

inherited

Default implementation of partial length calculation functionality.

Similar to length() member function but starts the calculation at the the field specified using TFromIdx template parameter, and stops the calculation at the the field specified using TUntilIdx template parameter.

Template Parameters

TFromIdx	Index of the field, from which length calculation will start
TUntilIdx	Index of the field, at which the calculation will stop. The length of the filed with index TUntilIdx will NOT be taken into account.

Returns

Calculated serialisation length

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doLengthUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TUntilIdx>

std::size_t comms::MessageBase< TMessage, TOptions >::doLengthUntil ( ) const

inherited

Default implementation of partial length calculation functionality.

Similar to length() member function but stops the calculation at the the field specified using TUntilIdx template parameter.

Template Parameters

TUntilIdx

Index of the field, at which the calculation will stop. The length of the filed with index TUntilIdx will NOT be taken into account.

Returns

Calculated serialisation length

Precondition

TUntilIdx <= std::tuple_size<AllFields>::value

doMaxLength()

template<typename TMessage , typename... TOptions>

static constexpr std::size_t comms::MessageBase< TMessage, TOptions >::doMaxLength ( )

staticconstexprinherited

Compile time constant of maximal serialisation length.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. To make this function works, every field class must provide "maxLength()" function with following signature:

static constexpr std::size_t maxLength();

Returns

Minimal serialisation length of the message.

doMaxLengthFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx>

static constexpr std::size_t comms::MessageBase< TMessage, TOptions >::doMaxLengthFrom ( )

staticconstexprinherited

Compile time constant of maximal partial serialisation length.

Similar to doMaxLength() member function but starts the calculation at the the field specified using TFromIdx template parameter.

Template Parameters

TFromIdx

Index of the field, from which length calculation will start

Returns

Calculated minimal serialisation length

Precondition

TFromIdx < std::tuple_size<AllFields>::value

doMaxLengthFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx>

std::size_t comms::MessageBase< TMessage, TOptions >::doMaxLengthFromUntil ( ) const

inherited

Compile time constant of maximal partial serialisation length.

Similar to doMaxLength() member function but starts the calculation at the the field specified using TFromIdx template parameter, and stops the calculation at the the field specified using TUntilIdx template parameter.

Template Parameters

TFromIdx	Index of the field, from which length calculation will start
TUntilIdx	Index of the field, at which the calculation will stop. The length of the filed with index TUntilIdx will NOT be taken into account.

Returns

Calculated minimal serialisation length

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doMaxLengthUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TUntilIdx>

static constexpr std::size_t comms::MessageBase< TMessage, TOptions >::doMaxLengthUntil ( )

staticconstexprinherited

Compile time constant of maximal partial serialisation length.

Similar to doMaxLength() member function but stops the calculation at the the field specified using TUntilIdx template parameter.

Template Parameters

TUntilIdx

Index of the field, at which the calculation will stop. The length of the filed with index TUntilIdx will NOT be taken into account.

Returns

Calculated minimal serialisation length

Precondition

TUntilIdx <= std::tuple_size<AllFields>::value

doMinLength()

template<typename TMessage , typename... TOptions>

static constexpr std::size_t comms::MessageBase< TMessage, TOptions >::doMinLength ( )

staticconstexprinherited

Compile time constant of minimal serialisation length.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. To make this function works, every field class must provide "minLength()" function with following signature:

static constexpr std::size_t minLength();

Returns

Minimal serialisation length of the message.

doMinLengthFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx>

static constexpr std::size_t comms::MessageBase< TMessage, TOptions >::doMinLengthFrom ( )

staticconstexprinherited

Compile time constant of minimal partial serialisation length.

Similar to doMinLength() member function but starts the calculation at the the field specified using TFromIdx template parameter.

Template Parameters

TFromIdx

Index of the field, from which length calculation will start

Returns

Calculated minimal serialisation length

Precondition

TFromIdx < std::tuple_size<AllFields>::value

doMinLengthFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx>

std::size_t comms::MessageBase< TMessage, TOptions >::doMinLengthFromUntil ( ) const

inherited

Compile time constant of minimal partial serialisation length.

Similar to doMinLength() member function but starts the calculation at the the field specified using TFromIdx template parameter, and stops the calculation at the the field specified using TUntilIdx template parameter.

Template Parameters

TFromIdx	Index of the field, from which length calculation will start
TUntilIdx	Index of the field, at which the calculation will stop. The length of the filed with index TUntilIdx will NOT be taken into account.

Returns

Calculated minimal serialisation length

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doMinLengthUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TUntilIdx>

static constexpr std::size_t comms::MessageBase< TMessage, TOptions >::doMinLengthUntil ( )

staticconstexprinherited

Compile time constant of minimal partial serialisation length.

Similar to doMinLength() member function but stops the calculation at the the field specified using TUntilIdx template parameter.

Template Parameters

TUntilIdx

Index of the field, at which the calculation will stop. The length of the filed with index TUntilIdx will NOT be taken into account.

Returns

Calculated minimal serialisation length

Precondition

TUntilIdx <= std::tuple_size<AllFields>::value

doName()

template<typename TMessage , typename TFieldOpts = comms::option::app::EmptyOption, typename TExtraOpts = comms::option::app::EmptyOption>

static const char * comms::GenericMessage< TMessage, TFieldOpts, TExtraOpts >::doName ( )

static

Get message name information.

The comms::MessageBase::nameImpl() will invoke this function.

doRead()

template<typename TMessage , typename... TOptions>

template<typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doRead ( TIter &  iter, std::size_t  size  )

inherited

Default implementation of read functionality.

This function exists only if comms::option::def::FieldsImpl option was provided to comms::MessageBase.
To make this function works, every field class must provide "read" function with following signature:

template <typename TIter>
ErrorStatus read(TIter& iter, std::size_t size);

This function will invoke such "read()" member function for every field object listed with comms::option::def::FieldsImpl option. If any field doesn't report ErrorStatus::Success, then read operation stops, i.e. the provided iterator is not advanced any more.

Template Parameters

TIter

Type of the iterator used for reading.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in]	size	Maximum number of bytes that can be read.

Returns

Status of the operation.

doReadFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doReadFrom ( TIter &  iter, std::size_t  len  )

protectedinherited

Helper function that allows to read only limited number of fields.

Sometimes the default implementation of doRead() is incorrect. For example, some bit in specific field specifies whether other field exists or must be skipped. In this case the derived class must implement different read functionality. To help in such task doReadUntil() function allows to read fields up to a specified one, while this function provides an ability to resume reading from some other field in the middle. The overriding doRead() function in the custom message definition class may use this function for such task. This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. The requirements from field classes is the same as explained in doRead() documentation.

Template Parameters

TIdx	Zero based index of the field to read from. The function reads all the fields between the one indexed TIdx (included) and the last one (also included).
TIter	Type of the iterator used for reading.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in]	len	Maximum number of bytes that can be read.

Returns

Status of the operation.

Precondition

TIdx < std::tuple_size<AllFields>::value

doReadFromAndUpdateLen()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doReadFromAndUpdateLen ( TIter &  iter, std::size_t &  len  )

protectedinherited

Same as doReadFrom(), but modifies length parameter.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in,out]	len	Maximum number of bytes that can be read.

doReadFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doReadFromUntil ( TIter &  iter, std::size_t  len  )

protectedinherited

Helper function that allows to read only limited number of fields.

Sometimes the default implementation of doRead() is incorrect. For example, some bit in specific field specifies whether other fields exist or must be skipped. In this case the derived class must implement different read functionality. In similar way to doReadFrom() and doReadUntil() this function provides an ability to read any number of fields. This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. The requirements from field classes is the same as explained in doRead() documentation.

Template Parameters

TFromIdx	Zero based index of the field to read from.
TUntilIdx	Zero based index of the field to read until (not included).
TIter	Type of the iterator used for reading.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in]	len	Maximum number of bytes that can be read.

Returns

Status of the operation.

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doReadFromUntilAndUpdateLen()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doReadFromUntilAndUpdateLen ( TIter &  iter, std::size_t &  len  )

protectedinherited

Same as doReadFromUntil(), but modifies length parameter.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in,out]	len	Maximum number of bytes that can be read.

doReadNoStatusFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

void comms::MessageBase< TMessage, TOptions >::doReadNoStatusFrom ( TIter &  iter )

protectedinherited

Helper function that allows to read only limited number of fields.

Similar to doReadFrom(), but doesn't check for errors and doesn't report status. This function can be used instead of doReadFrom() when correction of the read operation was ensured by other means prior to its invocation.

Template Parameters

TIdx	Zero based index of the field to read from. The function reads all the fields between the one indexed TIdx (included) and the last one (also included).
TIter	Type of the iterator used for reading.

Parameters

[in,out]

iter

Iterator used for reading the data.

Precondition

TIdx < std::tuple_size<AllFields>::value

doReadNoStatusFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >

void comms::MessageBase< TMessage, TOptions >::doReadNoStatusFromUntil ( TIter &  iter )

protectedinherited

Helper function that allows to read only limited number of fields.

Similar to doReadFromUntil(), but doesn't check for errors and doesn't report status. This function can be used instead of doReadFromUntil() when correction of the read operation was ensured by other means prior to its invocation.

Template Parameters

TFromIdx	Zero based index of the field to read from.
TUntilIdx	Zero based index of the field to read until (not included).
TIter	Type of the iterator used for reading.

Parameters

[in,out]

iter

Iterator used for reading the data.

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doReadNoStatusUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

void comms::MessageBase< TMessage, TOptions >::doReadNoStatusUntil ( TIter &  iter )

protectedinherited

Helper function that allows to read only limited number of fields.

Similar to doReadUntil(), but doesn't check for errors and doesn't report status. This function can be used instead of doReadUntil() when correction of the read operation was ensured by other means prior to its invocation.

Template Parameters

TIdx	Zero based index of the field to read until. The function returns when field with index "TIdx - 1" (if such exists) has been read, while field with index "TIdx" still hasn't.
TIter	Type of the iterator used for reading.

Parameters

[in,out]

iter

Iterator used for reading the data.

Precondition

TIdx <= std::tuple_size<AllFields>::value

doReadUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doReadUntil ( TIter &  iter, std::size_t &  len  )

protectedinherited

Helper function that allows to read only limited number of fields.

Sometimes the default implementation of doRead() is incorrect. For example, some bit in specific field specifies whether other field exists or must be skipped. In this case the derived class must implement different read functionality. To help in such task this function provides an ability to read all the fields up to (not including) requested field. The overriding doRead() function in the custom message definition class may use this function for such task. This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. The requirements from field classes is the same as explained in doRead() documentation.

Template Parameters

TIdx	Zero based index of the field to read until. The function returns when field with index "TIdx - 1" (if such exists) has been read, while field with index "TIdx" still hasn't.
TIter	Type of the iterator used for reading.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in]	len	Maximum number of bytes that can be read.

Returns

Status of the operation.

Precondition

TIdx <= std::tuple_size<AllFields>::value

doReadUntilAndUpdateLen()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doReadUntilAndUpdateLen ( TIter &  iter, std::size_t &  len  )

protectedinherited

Same as doReadUntil(), but updating length parameter.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in,out]	len	Maximum number of bytes that can be read.

doRefresh()

template<typename TMessage , typename... TOptions>

bool comms::MessageBase< TMessage, TOptions >::doRefresh ( ) const

inherited

Default implementation of refreshing functionality.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. To make this function works, every field class must provide "refresh()" function with following signature:

bool refresh() const;

This function will invoke such "refresh()" member function for every field object listed with comms::option::def::FieldsImpl option and will return true if at least one of the invoked functions returned true.

Returns

true when at least one of the fields has been updated.

doValid()

template<typename TMessage , typename... TOptions>

bool comms::MessageBase< TMessage, TOptions >::doValid ( ) const

inherited

Default implementation of validity check functionality.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. To make this function works, every field class must provide "valid()" function with following signature:

bool valid() const;

This function will invoke such "valid()" member function for every field object listed with comms::option::def::FieldsImpl option.

Returns

true when all fields are valid.

doWrite()

template<typename TMessage , typename... TOptions>

template<typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doWrite ( TIter &  iter, std::size_t  size  ) const

inherited

Default implementation of write functionality.

This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase.
To make this function works, every field class must provide "write" function with following signature:

template <typename TIter>
ErrorStatus write(TIter& iter, std::size_t size) const;

This function will invoke such "write()" member function for every field object listed with comms::option::def::FieldsImpl option. If any field doesn't report ErrorStatus::Success, then write operation stops, i.e. the provided iterator is not advanced any more.

Template Parameters

TIter

Type of the iterator used for writing.

Parameters

[in,out]	iter	Iterator used for writing the data.
[in]	size	Maximum number of bytes that can be written.

Returns

Status of the operation.

doWriteFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doWriteFrom ( TIter &  iter, std::size_t  len  ) const

protectedinherited

Helper function that allows to write only limited number of fields.

In a similar way to doReadFrom(), this function allows writing limited number of fields starting from the requested one until the end. This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. The requirements from field classes is the same as explained in doWrite() documentation.

Template Parameters

TIdx	Zero based index of the field to write from.
TIter	Type of iterator used for writing.

Parameters

[in,out]	iter	Iterator used for writing the data.
[in]	len	Maximum number of bytes that can be written.

Returns

Status of the operation.

Precondition

TIdx < std::tuple_size<AllFields>::value

doWriteFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doWriteFromUntil ( TIter &  iter, std::size_t  len  ) const

protectedinherited

Helper function that allows to write only limited number of fields.

In a similar way to doReadFromUntil(), this function allows writing limited number of fields between the requested indices. This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. The requirements from field classes is the same as explained in doWrite() documentation.

Template Parameters

TFromIdx	Zero based index of the field to write from.
TUntilIdx	Zero based index of the field to write until (not including).
TIter	Type of iterator used for writing.

Parameters

[in,out]	iter	Iterator used for writing the data.
[in]	len	Maximum number of bytes that can be written.

Returns

Status of the operation.

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doWriteNoStatusFrom()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

void comms::MessageBase< TMessage, TOptions >::doWriteNoStatusFrom ( TIter &  iter ) const

protectedinherited

Helper function that allows to write only limited number of fields.

Similar to doWriteFrom(), but doesn't check for errors and doesn't report status. This function can be used instead of doWriteFrom() when correction of the write operation was ensured by other means prior to its invocation.

Template Parameters

TIdx	Zero based index of the field to write from.
TIter	Type of the iterator used for writing.

Parameters

[in,out]

iter

Iterator used for reading the data.

Precondition

TIdx < std::tuple_size<AllFields>::value

doWriteNoStatusFromUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TFromIdx, std::size_t TUntilIdx, typename TIter >

void comms::MessageBase< TMessage, TOptions >::doWriteNoStatusFromUntil ( TIter &  iter ) const

protectedinherited

Helper function that allows to write only limited number of fields.

Similar to doWriteFromUntil(), but doesn't check for errors and doesn't report status. This function can be used instead of doWriteFromUntil() when correction of the write operation was ensured by other means prior to its invocation.

Template Parameters

TFromIdx	Zero based index of the field to write from.
TUntilIdx	Zero based index of the field to write until (not including).
TIter	Type of iterator used for writing.

Parameters

[in,out]

iter

Iterator used for reading the data.

Precondition

TFromIdx < std::tuple_size<AllFields>::value

TUntilIdx <= std::tuple_size<AllFields>::value

TFromIdx < TUntilIdx

doWriteNoStatusUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

void comms::MessageBase< TMessage, TOptions >::doWriteNoStatusUntil ( TIter &  iter ) const

protectedinherited

Helper function that allows to write only limited number of fields.

Similar to doWriteUntil(), but doesn't check for errors and doesn't report status. This function can be used instead of doWriteUntil() when correction of the write operation was ensured by other means prior to its invocation.

Template Parameters

TIdx	Zero based index of the field to write until. The function returns when field with index "TIdx - 1" (if such exists) has been written, while field with index "TIdx" still hasn't.
TIter	Type of the iterator used for writing.

Parameters

[in,out]

iter

Iterator used for reading the data.

Precondition

TIdx <= std::tuple_size<AllFields>::value

doWriteUntil()

template<typename TMessage , typename... TOptions>

template<std::size_t TIdx, typename TIter >

ErrorStatus comms::MessageBase< TMessage, TOptions >::doWriteUntil ( TIter &  iter, std::size_t  len  ) const

protectedinherited

Helper function that allows to write only limited number of fields.

In a similar way to doReadUntil(), this function allows writing limited number of fields starting from the first one. This function exists only if comms::option::def::FieldsImpl or comms::option::def::ZeroFieldsImpl option was provided to comms::MessageBase. The requirements from field classes is the same as explained in doWrite() documentation.

Template Parameters

TIdx	Zero based index of the field to write until. The function returns when field with index "TIdx - 1" (if such exists) has been written, while field with index "TIdx" still hasn't.
TIter	Type of iterator used for writing.

Parameters

[in,out]	iter	Iterator used for writing the data.
[in]	len	Maximum number of bytes that can be written.

Returns

Status of the operation.

Precondition

TIdx <= std::tuple_size<AllFields>::value

fields() [1/2]

template<typename TMessage , typename... TOptions>

AllFields & comms::MessageBase< TMessage, TOptions >::fields ( )

inherited

Get an access to the fields of the message.

The function doesn't exist if comms::option::def::FieldsImpl option wasn't provided to comms::MessageBase.

Returns

Reference to the fields of the message.

fields() [2/2]

template<typename TMessage , typename... TOptions>

const AllFields & comms::MessageBase< TMessage, TOptions >::fields ( ) const

inherited

Get an access to the fields of the message.

The function doesn't exist if comms::option::def::FieldsImpl option wasn't provided to comms::MessageBase.

Returns

Const reference to the fields of the message.

getId()

template<typename... TOptions>

MsgIdParamType comms::Message< TOptions >::getId ( ) const

inherited

Retrieve ID of the message.

Invokes pure virtual getIdImpl(). This function exists only if comms::option::def::MsgIdType option was used to specify type of the ID value and comms::option::app::IdInfoInterface option are used.

Returns

ID of the message.

See also

hasGetId();

getIdImpl()

template<typename TMessage , typename... TOptions>

virtual MsgIdParamType comms::MessageBase< TMessage, TOptions >::getIdImpl ( ) const

overrideprotectedvirtualinherited

Implementation of ID retrieval functionality.

This function may exist only if ID retrieval is possible, i.e. the ID type has been privded to comms::Message using comms::option::def::MsgIdType option and the polymorphic ID retrieval functionality was requested (using comms::option::app::IdInfoInterface). In addition to the conditions listed earlier this function is provided if local doGetId() function was generated. If not, it may still be provided if the derived class is known (comms::option::def::MsgType option was used) and the comms::option::def::HasDoGetId option is used to declare the derived type having doGetId() member function defined.

Returns

ID value passed as template parameter to comms::option::def::StaticNumIdImpl option.

Implements comms::Message< TOptions >.

length()

template<typename... TOptions>

std::size_t comms::Message< TOptions >::length ( ) const

inherited

Get number of bytes required to serialise this message.

The function exists only if comms::option::app::LengthInfoInterface option was provided to comms::Message. The function invokes virtual lengthImpl() function.

Returns

Number of bytes required to serialise this message.

See also

hasLength()

lengthImpl()

template<typename TMessage , typename... TOptions>

virtual std::size_t comms::MessageBase< TMessage, TOptions >::lengthImpl ( ) const

overrideprotectedvirtualinherited

Implementation of polymorphic length calculation functionality.

This function exists if comms::option::app::LengthInfoInterface option was provided to comms::Message class when specifying interface, and comms::option::app::NoLengthImpl option was NOT used to inhibit the implementation.
If comms::option::def::MsgType option was used to specify the actual type of the message, and if it contains custom doLength() function, it will be invoked. Otherwise, the invocation of comms::MessageBase::doLength() will be chosen in case fields were specified using comms::option::def::FieldsImpl option.

Returns

Serialisation length of the message.

Reimplemented from comms::Message< TOptions >.

name()

template<typename... TOptions>

const char * comms::Message< TOptions >::name ( ) const

inherited

Get name of the message.

The function exists only if comms::option::app::NameInterface option was provided to comms::Message. The function invokes virtual nameImpl() function.

See also

hasName()

nameImpl()

template<typename TMessage , typename... TOptions>

virtual const char * comms::MessageBase< TMessage, TOptions >::nameImpl ( ) const

overrideprotectedvirtualinherited

Implementation of polymorphic name retrieval functionality.

This function exists if comms::option::app::NameInterface option was provided to comms::Message class when specifying interface, and comms::option::def::HasName as well as comms::option::def::MsgType options ware used for this class. This function downcasts this pointer to actual message type and invokes doName() member function.

Returns

true in case fields were updated, false if nothing has changed.

Implements comms::Message< TOptions >.

read()

template<typename... TOptions>

ErrorStatus comms::Message< TOptions >::read ( ReadIterator &  iter, std::size_t  size  )

inherited

Read message contents using provided iterator.

The function exists only if comms::option::app::ReadIterator option was provided to comms::Message to specify type of the ReadIterator. The contents of the message are updated with bytes being read. The buffer is external and maintained by the caller. The provided iterator is advanced. The function invokes virtual readImpl() function.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in]	size	Maximum number of bytes that can be read.

Returns

Status of the operation.

See also

hasRead()

readData() [1/2]

template<typename... TOptions>

template<typename T , typename TIter >

static T comms::Message< TOptions >::readData ( TIter &  iter )

staticprotectedinherited

Read data from input area.

Use this function to read data from the input area using provided iterator. This function requires knowledge about serialisation endian. It exists only if endian type was specified using comms::option::def::BigEndian or comms::option::def::LittleEndian options to the class.

Template Parameters

T	Return type
TIter	Type of input iterator

Parameters

[in,out]

iter

Input iterator.

Returns

The integral type value.

Precondition

TSize <= sizeof(T)

The iterator must be valid and can be successfully dereferenced and incremented at least sizeof(T) times.

Postcondition

The iterator is advanced.

Note

Thread safety: Safe for distinct stream buffers, unsafe otherwise.

readData() [2/2]

template<typename... TOptions>

template<typename T , std::size_t TSize, typename TIter >

static T comms::Message< TOptions >::readData ( TIter &  iter )

staticprotectedinherited

Read partial data from input area.

Use this function to read partial data from the input area using provided iterator. This function requires knowledge about serialisation endian. It exists only if endian type was specified using comms::option::def::BigEndian or comms::option::def::LittleEndian options to the class.

Template Parameters

T	Return type
TSize	number of bytes to read
TIter	Type of input iterator

Parameters

[in,out]

iter

Input iterator.

Returns

The integral type value.

Precondition

TSize <= sizeof(T)

The iterator must be valid and can be successfully dereferenced and incremented at least TSize times.

Postcondition

The internal pointer of the stream buffer is advanced.

Note

Thread safety: Safe for distinct stream buffers, unsafe otherwise.

readImpl()

template<typename TMessage , typename... TOptions>

virtual ErrorStatus comms::MessageBase< TMessage, TOptions >::readImpl ( ReadIterator &  iter, std::size_t  size  )

overrideprotectedvirtualinherited

Implementation of polymorphic read functionality.

This function exists if comms::option::app::ReadIterator option was provided to comms::Message class when specifying interface, and comms::option::app::NoReadImpl option was NOT used to inhibit the implementation.
If comms::option::def::MsgType option was used to specify the actual type of the message, and if it contains custom doRead() function, it will be invoked. Otherwise, the invocation of comms::MessageBase::doRead() will be chosen in case fields were specified using comms::option::def::FieldsImpl option.

Parameters

[in,out]	iter	Iterator used for reading the data.
[in]	size	Maximum number of bytes that can be read.

Returns

Status of the operation.

Reimplemented from comms::Message< TOptions >.

refresh()

template<typename... TOptions>

bool comms::Message< TOptions >::refresh ( )

inherited

Refresh to contents of the message.

Many protocols define their messages in a way that the content of some fields may depend on the value of the other field(s). For example, providing in one field the information about number of elements in the list that will follow later. Another example is having bits in a bitmask field specifying whether other optional fields exist. In this case, directly modifying value of some fields may leave a message contents in an inconsistent state. Having refresh() member function allows the developer to bring the message into a consistent state prior to sending it over I/O link .
The function exists only if comms::option::app::RefreshInterface option was provided to comms::Message. The function invokes virtual refreshImpl() function.

Returns

true in case the contents of the message were modified, false if all the fields of the message remained unchanged.

refreshImpl()

template<typename TMessage , typename... TOptions>

virtual bool comms::MessageBase< TMessage, TOptions >::refreshImpl ( )

overrideprotectedvirtualinherited

Implementation of polymorphic refresh functionality.

This function exists if comms::option::app::RefreshInterface option was provided to comms::Message class when specifying interface, and comms::option::def::HasCustomRefresh option was used (either on on of the fields or when defining a message class) to to notify about existence of custom refresh functionality. If comms::option::def::MsgType option was used to specify the actual message class, the this pointer will be downcasted to it to invoke doRefresh() member function defined there. If such is not defined the default doRefresh() member function from this class will be used.

Returns

true in case fields were updated, false if nothing has changed.

Reimplemented from comms::Message< TOptions >.

staticMsgId()

template<typename TMessage , typename... TOptions>

static constexpr std::intmax_t comms::MessageBase< TMessage, TOptions >::staticMsgId ( )

staticconstexprinherited

Compile time retrieval of the message id provided via comms::option::def::StaticNumIdImpl.

If comms::option::def::StaticNumIdImpl hasn't been used, std::numeric_limits<std::intmax_t>::max() is returned.

transportFields() [1/2]

template<typename... TOptions>

TransportFields & comms::Message< TOptions >::transportFields ( )

inherited

Get access to extra transport fields.

The function exists only if comms::option::def::ExtraTransportFields option has been provided to comms::Message class to specify them. Some protocols may use additional values in transport information, such as message version for example. Such values may influence the way message data is being serialized / deserialized. The provided extra transport fields are NOT serialised as part of message payload. Their values are expected to be set by transport layer(s) when such information is read. The transport layers are also responsible to take the updated information from the relevant field and write it when message contents being written.

See also

hasTransportFields()

transportFields() [2/2]

template<typename... TOptions>

const TransportFields & comms::Message< TOptions >::transportFields ( ) const

inherited

Const version of transportFields.

The function exists only if comms::option::def::ExtraTransportFields option has been provided to comms::Message class to specify them.

See also

hasTransportFields()

valid()

template<typename... TOptions>

bool comms::Message< TOptions >::valid ( ) const

inherited

Check validity of message contents.

The function exists only if comms::option::app::ValidCheckInterface option was provided to comms::Message. The function invokes virtual validImpl() function.

Returns

true for valid contents, false otherwise.

See also

hasValid()

validImpl()

template<typename TMessage , typename... TOptions>

virtual bool comms::MessageBase< TMessage, TOptions >::validImpl ( ) const

overrideprotectedvirtualinherited

Implementation of polymorphic validity check functionality.

This function exists if comms::option::app::ValidCheckInterface option was provided to comms::Message class when specifying interface, and comms::option::app::NoValidImpl option was NOT used to inhibit the implementation.
If comms::option::def::MsgType option was used to specify the actual type of the message, and if it contains custom doValid() function, it will be invoked. Otherwise, the invocation of comms::MessageBase::doValid() will be chosen in case fields were specified using comms::option::def::FieldsImpl option.

Reimplemented from comms::Message< TOptions >.

version() [1/2]

template<typename... TOptions>

VersionType & comms::Message< TOptions >::version ( )

inherited

Access to version information.

The function exists only if comms::option::def::VersionInExtraTransportFields option has been provided.

version() [2/2]

template<typename... TOptions>

const VersionType & comms::Message< TOptions >::version ( ) const

inherited

Const access to version information.

The function exists only if comms::option::def::VersionInExtraTransportFields option has been provided.

versionIdxInTransportFields()

template<typename... TOptions>

static constexpr std::size_t comms::Message< TOptions >::versionIdxInTransportFields ( )

staticconstexprinherited

Compile type inquiry of version field index in transport field.

If comms::option::def::VersionInExtraTransportFields option hasn't been used, the std::numeric_limits<std::size_t>::max() is returned.

write()

template<typename... TOptions>

ErrorStatus comms::Message< TOptions >::write ( WriteIterator &  iter, std::size_t  size  ) const

inherited

Write message contents using provided iterator.

The function exists only if comms::option::app::WriteIterator option was provided to comms::Message to specify type of the WriteIterator. The contents of the message are serialised into buffer. The buffer is external and is maintained by the caller. The provided iterator is advanced. The function invokes virtual writeImpl() function.

Parameters

[in,out]	iter	Iterator used for writing the data.
[in]	size	Maximum number of bytes that can be written.

Returns

Status of the operation.

See also

hasWrite()

writeData() [1/2]

template<typename... TOptions>

template<typename T , typename TIter >

static void comms::Message< TOptions >::writeData ( T  value, TIter &  iter  )

staticprotectedinherited

Write data into the output area.

Use this function to write data to the output area using provided iterator. This function requires knowledge about serialisation endian. It exists only if endian type was specified using comms::option::def::BigEndian or comms::option::def::LittleEndian options to the class.

Template Parameters

T	Type of the value to write. Must be integral.
Type	of output iterator

Parameters

[in]	value	Integral type value to be written.
[in,out]	iter	Output iterator.

Precondition

The iterator must be valid and can be successfully dereferenced and incremented at least sizeof(T) times.

Postcondition

The iterator is advanced.

Note

Thread safety: Safe for distinct buffers, unsafe otherwise.

writeData() [2/2]

template<typename... TOptions>

template<std::size_t TSize, typename T , typename TIter >

static void comms::Message< TOptions >::writeData ( T  value, TIter &  iter  )

staticprotectedinherited

Write partial data into the output area.

Use this function to write partial data to the output area using provided iterator. This function requires knowledge about serialisation endian. It exists only if endian type was specified using comms::option::def::BigEndian or comms::option::def::LittleEndian options to the class.

Template Parameters

TSize	Length of the value in bytes known in compile time.
T	Type of the value to write. Must be integral.
TIter	Type of output iterator

Parameters

[in]	value	Integral type value to be written.
[in,out]	iter	Output iterator.

Precondition

TSize <= sizeof(T)

The iterator must be valid and can be successfully dereferenced and incremented at least TSize times.

Postcondition

The iterator is advanced.

Note

Thread safety: Safe for distinct buffers, unsafe otherwise.

writeImpl()

template<typename TMessage , typename... TOptions>

virtual ErrorStatus comms::MessageBase< TMessage, TOptions >::writeImpl ( WriteIterator &  iter, std::size_t  size  ) const

overrideprotectedvirtualinherited

Implementation of polymorphic write functionality.

This function exists if comms::option::app::WriteIterator option was provided to comms::Message class when specifying interface, and comms::option::app::NoWriteImpl option was NOT used to inhibit the implementation.
If comms::option::def::MsgType option was used to specify the actual type of the message, and if it contains custom doWrite() function, it will be invoked. Otherwise, the invocation of comms::MessageBase::doWrite() will be chosen in case fields were specified using comms::option::def::FieldsImpl option.

Parameters

[in,out]	iter	Iterator used for writing the data.
[in]	size	Maximum number of bytes that can be written.

Returns

Status of the operation.

Reimplemented from comms::Message< TOptions >.

Friends And Related Symbol Documentation

COMMS_MSG_FIELD_ALIAS

template<typename TMessage , typename... TOptions>

#define COMMS_MSG_FIELD_ALIAS (   f_,   ...  )

related

Value:

    COMMS_EXPAND(COMMS_MSG_FIELD_ALIAS_ACCESS(f_, __VA_ARGS__)) \
    COMMS_EXPAND(COMMS_DO_ALIAS_TYPEDEF(Field_, f_, __VA_ARGS__))

Generate convinience alias types and access member functions for other member fields.

The COMMS_MSG_FIELDS_NAMES() macro generates inner types and convenience access member functions for member fields. Sometimes the fields may get renamed or moved to be a member of other fields, like comms::field::Bundle or comms::field::Bitfield. In such case the compilation of the existing client code (that already uses published protocol definition) may fail. To avoid such scenarios and make the transition to newer versions of the protocol easier, the COMMS_MSG_FIELD_ALIAS() macro can be used to create alias to other fields. For example, let's assume that some message class was defined: like this.

class Message1 : public comms::MessageBase<...>
{
    using Base = comms::MessageBase<...>;
public:
    COMMS_MSG_FIELDS_NAMES(name1, name2, name3);
};

In the future versions of the protocol "name3" was renamed to "newName3". To keep the existing code (that uses "name3" name) compiling it is possible to create an alias access function(s) with:

class Message1 : public comms::MessageBase<...>
{
    using Base = comms::MessageBase<...>;
public:
    COMMS_MSG_FIELDS_NAMES(name1, name2, newName3);
    COMMS_MSG_FIELD_ALIAS(name3, newName3);
};

The usage of COMMS_MSG_FIELD_ALIAS() in the code above is equivalent to having the following functions as well as type defined:

class Message1 : public comms::MessageBase<...>
{
public:
    ...
 
    using Field_name3 = Field_newName3;
 
    auto field_name3() -> decltype(field_newName3())
    {
        return field_newName3();
    }
 
    auto field_name3() const -> decltype(field_newName3())
    {
        return field_newName3();
    }
};

Another example would be a replacing a comms::field::IntValue with comms::field::Bitfield in the future version of the protocol. It can happen when the developer decides to split the used storage into multiple values (because the range of the used/valid values allows so). In order to keep the old client code compiling, the access to the replaced field needs to be an alias to the first member of the comms::field::Bitfield. In this case the usage of COMMS_MSG_FIELD_ALIAS() will look like this:

class Message1 : public comms::MessageBase<...>
{
    using Base = comms::MessageBase<...>;
public:
    COMMS_MSG_FIELDS_NAMES(name1, name2, newName3);
    COMMS_MSG_FIELD_ALIAS(name3, newName3, member1);
};

The usage of COMMS_MSG_FIELD_ALIAS() in the code above is equivalent to having the following functions defined:

class Message1 : public comms::MessageBase<...>
{
public:
    ...
 
    using Field_name3 = typename Field_newName3::Field_member1;
 
    auto field_name3() -> decltype(field_newName3().field_member1())
    {
        return field_newName3().field_member1();
    }
 
    auto field_name3() const -> decltype(field_newName3().field_member1())
    {
        return field_newName3().field_member1();
    }
};

Parameters

[in]	f_	Alias field name.
[in]	...	List of fields' names.

Precondition

The macro COMMS_MSG_FIELDS_NAMES() needs to be used before COMMS_MSG_FIELD_ALIAS() to define convenience access functions.

See also

COMMS_MSG_FIELD_ALIAS_ACCESS()

Note

Defined in "comms/MessageBase.h"

COMMS_MSG_FIELD_ALIAS_ACCESS

template<typename TMessage , typename... TOptions>

#define COMMS_MSG_FIELD_ALIAS_ACCESS (   f_,   ...  )    COMMS_DO_ALIAS(field_, f_, __VA_ARGS__)

related

Generate convinience alias access member functions for other member fields.

Similar to COMMS_MSG_FIELD_ALIAS() but requires usage of COMMS_MSG_FIELDS_ACCESS() instead of COMMS_MSG_FIELDS_NAMES() and does NOT create alias to the field type, only access functions.

Parameters

[in]	f_	Alias field name.
[in]	...	List of fields' names.

Precondition

The macro COMMS_MSG_FIELDS_ACCESS() needs to be used before COMMS_MSG_FIELD_ALIAS_ACCESS() to define convenience access functions.

Note

Defined in "comms/MessageBase.h"

See also

COMMS_MSG_FIELD_ALIAS()

COMMS_MSG_FIELDS_ACCESS

template<typename TMessage , typename... TOptions>

#define COMMS_MSG_FIELDS_ACCESS (   ... )

related

Value:

    COMMS_EXPAND(COMMS_DEFINE_FIELD_ENUM(__VA_ARGS__)) \
    COMMS_MSG_FIELDS_ACCESS_FUNC { \
        auto& val = comms::toMessageBase(*this).fields(); \
        using AllFieldsTuple = typename std::decay<decltype(val)>::type; \
        static_assert(std::tuple_size<AllFieldsTuple>::value == FieldIdx_numOfValues, \
            "Invalid number of names for fields tuple"); \
        return val; \
    } \
    COMMS_MSG_FIELDS_ACCESS_CONST_FUNC { \
        auto& val = comms::toMessageBase(*this).fields(); \
        using AllFieldsTuple =  typename std::decay<decltype(val)>::type; \
        static_assert(std::tuple_size<AllFieldsTuple>::value == FieldIdx_numOfValues, \
            "Invalid number of names for fields tuple"); \
        return val; \
    } \
    COMMS_EXPAND(COMMS_DO_FIELD_ACC_FUNC(AllFields, fields(), __VA_ARGS__))

Add convenience access enum and functions to message fields.

Very similar to COMMS_MSG_FIELDS_NAMES(), but does NOT require definition of Base inner member type (for some compilers) and does NOT define inner Field_* types for used fields.

Parameters

[in]

...

List of fields' names.

See also

COMMS_MSG_FIELDS_NAMES()

Note

Defined in "comms/MessageBase.h"

COMMS_MSG_FIELDS_NAMES

template<typename TMessage , typename... TOptions>

#define COMMS_MSG_FIELDS_NAMES (   ... )

related

Value:

    COMMS_EXPAND(COMMS_MSG_FIELDS_ACCESS(__VA_ARGS__)) \
    COMMS_EXPAND(COMMS_DO_FIELD_TYPEDEF(typename Base::AllFields, Field_, FieldIdx_, __VA_ARGS__))

Provide names for message fields.

The comms::MessageBase class provides access to its fields via comms::MessageBase::fields() member function(s). The fields are bundled into std::tuple and can be accessed using indices with std::get. For convenience, the fields should be named. The COMMS_MSG_FIELDS_NAMES() macro does exactly that.
As an example, let's assume that custom message uses 3 fields of any types:

using Field1 = ... /* some field definition */;
using Field2 = ... /* some field definition */;
using Field3 = ... /* some field definition */;
 
using Message1Fields = std::tuple<Field1, Field2, Field3>;
 
class Message1 : public
    comms::MessageBase<
        MyInterface,
        comms::option::def::FieldsImpl<Message1Fields>,
        ... /* some other options */>
{
    // Base class (re) definition required by COMMS_MSG_FIELDS_NAMES()
    using Base =
        comms::MessageBase<
            MyInterface,
            comms::option::def::FieldsImpl<Message1Fields>,
            ... /* some other options */>
public:
    // Provide names for message fields
    COMMS_MSG_FIELDS_NAMES(name1, name2, name3);
};

NOTE that there is a required to have Base member type that specifies base class used. It is needed to be able to access comms::MessageBase::AllFields type definition.

The usage of the COMMS_MSG_FIELDS_NAMES() macro with the list of the field's names is equivalent to having the following definitions inside the message class

class Message1 : public comms::MessageBase<...>
{
    using Base = comms::MessageBase<...>;
public:
    // Indices of the fields
    enum FieldIdx {
        FieldIdx_name1,
        FieldIdx_name2,
        FieldIdx_name3,
        FieldIdx_nameOfValues
    };
 
    static_assert(std::tuple_size<Base::AllFields>::value == FieldIdx_nameOfValues,
        "Number of expected fields is incorrect");
 
    // Accessor to "name1" field.
    auto field_name1() -> decltype(std::get<FieldIdx_name1>(Base::fields()))
    {
        return std::get<FieldIdx_name1>(Base::fields());
    }
 
    // Accessor to "name1" field.
    auto field_name1() const -> decltype(std::get<FieldIdx_name1>(Base::fields()))
    {
        return std::get<FieldIdx_name1>(Base::fields());
    }
 
    // Accessor to "name2" field.
    auto field_name2() -> decltype(std::get<FieldIdx_name2>(Base::fields()))
    {
        return std::get<FieldIdx_name2>(Base::fields());
    }
 
    // Accessor to "name2" field.
    auto field_name2() const -> decltype(std::get<FieldIdx_name2>(Base::fields()))
    {
        return std::get<FieldIdx_name2>(Base::fields());
    }
 
    // Accessor to "name3" field.
    auto field_name3() -> decltype(std::get<FieldIdx_name3>(Base::fields()))
    {
        return std::get<FieldIdx_name3>(Base::fields());
    }
 
    // Accessor to "name3" field.
    auto field_name3() const -> decltype(std::get<FieldIdx_name3>(Base::fields()))
    {
        return std::get<FieldIdx_name3>(Base::fields());
    }
 
    // Redefinition of the field types:
    using Field_name1 = Field1;
    using Field_name2 = Field2;
    using Field_name3 = Field3;
};

NOTE, that provided names name1, name2, and name3 have found their way to the following definitions:

• FieldIdx enum. The names are prefixed with FieldIdx_. The FieldIdx_nameOfValues value is automatically added at the end.
• Accessor functions prefixed with field_*
• Types of fields prefixed with Field_*

As the result, the fields can be accessed using FieldIdx enum

void handle(Message1& msg)
{
    auto& allFields = msg.fields();
    auto& field1 = std::get<Message1::FieldIdx_name1>(allFields);
    auto& field2 = std::get<Message1::FieldIdx_name2>(allFields);
    auto& field3 = std::get<Message1::FieldIdx_name3>(allFields);
 
    auto value1 = field1.value();
    auto value2 = field2.value();
    auto value3 = field3.value();
}

or using accessor functions:

void handle(Message1& msg)
{
    auto value1 = field_name1().value();
    auto value2 = field_name2().value();
    auto value3 = field_name3().value();
}

Parameters

[in]

...

List of fields' names.

Precondition

Requires (re)definition of the message base class as inner Base member type.

See also

COMMS_MSG_FIELDS_ACCESS()

Note

Defined in "comms/MessageBase.h"

COMMS_MSG_TRANSPORT_FIELD_ALIAS

template<typename... TOptions>

#define COMMS_MSG_TRANSPORT_FIELD_ALIAS (   f_,   ...  )

related

Value:

    COMMS_EXPAND(COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS(f_, __VA_ARGS__)) \
    COMMS_EXPAND(COMMS_DO_ALIAS_TYPEDEF(TransportField_, f_, __VA_ARGS__))

Generate convinience alias access member functions for extra member transport fields.

The COMMS_MSG_TRANSPORT_FIELDS_NAMES() macro generates alias type as well as convenience access member functions for extra transport fields. Sometimes the fields may get renamed or moved to be a member of other fields, like comms::field::Bundle or comms::field::Bitfield. In such case the compilation of the existing client code (that already uses published protocol definition) may fail. To avoid such scenarios and make the transition to newer versions of the protocol easier, the COMMS_MSG_TRANSPORT_FIELD_ALIAS() macro can be used to create alias to other fields. For example, let's assume that some common interface class was defined: like this.

class MyInterface : public comms::Message<...>
{
    // (Re)definition of the base class as inner Base type.
    using Base = comms::Message<...>;
public:
    COMMS_MSG_TRANSPORT_FIELDS_NAMES(name1, name2, name3);
};

In the future versions of the protocol "name3" was renamed to "newName3". To keep the existing code (that uses "name3" name) compiling it is possible to create an alias access function(s) with:

class MyInterface : public public comms::Message<...>
{
    using Base = comms::Message<...>;
public:
    COMMS_MSG_TRANSPORT_FIELDS_NAMES(name1, name2, newName3);
    COMMS_MSG_TRANSPORT_FIELD_ALIAS(name3, newName3);
};

The usage of COMMS_MSG_TRANSPORT_FIELD_ALIAS() in the code above is equivalent to having the following type and functions defined:

class MyInterface : public public comms::Message<...>
{
public:
    ...
    using TransportField_name3 = TransportField_newName3;
 
    auto transportField_name3() -> decltype(transportField_newName3())
    {
        return transportField_newName3();
    }
 
    auto transportField_name3() const -> decltype(transportField_newName3())
    {
        return transportField_newName3();
    }
};

Another example would be a replacing a comms::field::IntValue with comms::field::Bitfield in the future version of the protocol. It can happen when the developer decides to split the used storage into multiple values (because the range of the used/valid values allows so). In order to keep the old client code compiling, the access to the replaced field needs to be an alias to the first member of the comms::field::Bitfield. In this case the usage of COMMS_MSG_TRANSPORT_FIELD_ALIAS() will look like this:

class MyInterface : public public comms::Message<...>
{
    using Base = comms::Message<...>;
public:
    COMMS_MSG_TRANSPORT_FIELDS_NAMES(name1, name2, newName3);
    COMMS_MSG_TRANSPORT_FIELD_ALIAS(name3, newName3, member1);
};

The usage of COMMS_MSG_TRANSPORT_FIELD_ALIAS() in the code above is equivalent to having the following functions defined:

class MyInterface : public public comms::Message<...>
{
public:
    ...
    using TransportField_name3 = TransportField_newName3::Field_Member1;
 
    auto transportField_name3() -> decltype(transportField_newName3().field_member1())
    {
        return field_newName3().field_member1();
    }
 
    auto transportField_name3() const -> decltype(transportField_newName3().field_member1())
    {
        return transportField_newName3().field_member1();
    }
};

Parameters

[in]	f_	Alias field name.
[in]	...	List of fields' names.

Precondition

The macro COMMS_MSG_TRANSPORT_FIELDS_NAMES() needs to be used before COMMS_MSG_TRANSPORT_FIELD_ALIAS() to define convenience access functions.

See also

COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS_NOTEMPLATE()

COMMS_MSG_TRANSPORT_FIELD_ALIAS_NOTEMPLATE()

Note

Defined in "comms/Message.h"

COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS

template<typename... TOptions>

#define COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS (   f_,   ...  )    COMMS_EXPAND(COMMS_DO_ALIAS(transportField_, f_, __VA_ARGS__))

related

Generate convinience alias access member functions for extra member transport fields.

Similar to COMMS_MSG_TRANSPORT_FIELD_ALIAS() but requires usage of COMMS_MSG_TRANSPORT_FIELDS_ACCESS() instead of COMMS_MSG_TRANSPORT_FIELDS_NAMES() and does NOT create alias to the field type, only access functions.

Parameters

[in]	f_	Alias field name.
[in]	...	List of fields' names.

Precondition

The macro COMMS_MSG_TRANSPORT_FIELDS_ACCESS() needs to be used before COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS() to define convenience access functions.

See also

COMMS_MSG_TRANSPORT_FIELD_ALIAS_ACCESS_NOTEMPLATE()

COMMS_MSG_TRANSPORT_FIELD_ALIAS()

Note

Defined in "comms/Message.h"

COMMS_MSG_TRANSPORT_FIELDS_ACCESS

template<typename... TOptions>

#define COMMS_MSG_TRANSPORT_FIELDS_ACCESS (   ... )

related

Value:

    COMMS_EXPAND(COMMS_DEFINE_TRANSPORT_FIELD_ENUM(__VA_ARGS__)) \
    COMMS_MSG_TRANSPORT_FIELDS_ACCESS_FUNC { \
        auto& msgBase = comms::toMessage(*this); \
        using MsgBase = typename std::decay<decltype(msgBase)>::type; \
        static_assert(MsgBase::hasTransportFields(), \
            "Message interface class doesn't define extra transport fields."); \
        using TransportFieldsTuple = typename MsgBase::TransportFields; \
        static_assert(std::tuple_size<TransportFieldsTuple>::value == TransportFieldIdx_numOfValues, \
            "Invalid number of names for transport fields tuple"); \
        return msgBase.transportFields(); \
    } \
    COMMS_MSG_TRANSPORT_FIELDS_ACCESS_CONST_FUNC { \
        return comms::toMessage(*this).transportFields(); \
    } \
    COMMS_EXPAND(COMMS_DO_TRANSPORT_FIELD_ACC_FUNC(TransportFields, transportFields(), __VA_ARGS__))

Add convenience access enum and functions to extra transport fields.

Very similar to COMMS_MSG_TRANSPORT_FIELDS_NAMES(), but does NOT require definition of Base inner member type (for some compilers) and does NOT define inner TransportField_* types for used fields.

Parameters

[in]

...

List of fields' names.

See also

COMMS_MSG_TRANSPORT_FIELDS_NAMES()

Note

Defined in "comms/Message.h"

COMMS_MSG_TRANSPORT_FIELDS_NAMES

template<typename... TOptions>

#define COMMS_MSG_TRANSPORT_FIELDS_NAMES (   ... )

related

Value:

    COMMS_EXPAND(COMMS_MSG_TRANSPORT_FIELDS_ACCESS(__VA_ARGS__)) \
    COMMS_EXPAND(COMMS_DO_FIELD_TYPEDEF(typename Base::TransportFields, TransportField_, TransportFieldIdx_, __VA_ARGS__))

Provide names for extra transport fields.

The comms::Message class provides access to its extra transport fields via comms::MessageBase::transportFields() member function(s). The fields are bundled into std::tuple and can be accessed using indices with std::get. For convenience, the fields should be named. The COMMS_MSG_TRANSPORT_FIELDS_NAMES() macro does exactly that.
As an example, let's assume that custom message uses 3 fields of any types:

using TransportField1 = ...;
using TransportField2 = ...;
using TransportField3 = ...;
 
typedef std::tuple<TransportField1, TransportField2, TransportField3> MyExtraTransportFields
 
class MyInterface : public
    comms::Message<
        ...
        comms::option::def::ExtraTransportFields<MyExtraTransportFields> >
{
    // (Re)definition of the base class as inner Base type is
    // required by the COMMS_MSG_TRANSPORT_FIELDS_NAMES() macro.
    using Base = comms::Message<...>;
public:
    COMMS_MSG_TRANSPORT_FIELDS_NAMES(name1, name2, name3);
};

The usage of the COMMS_MSG_TRANSPORT_FIELDS_NAMES() macro with the list of the extra transport field's names is equivalent to having the following definitions inside the message class

class MyInterface : public comms::Message<...>
{
    using Base = comms::Message<...>;
public:
    enum TransportFieldIdx {
        TransportFieldIdx_name1,
        TransportFieldIdx_name2,
        TransportFieldIdx_name3,
        TransportFieldIdx_nameOfValues
    };
 
    static_assert(std::tuple_size<Base::TransportFields>::value == TransportFieldIdx_nameOfValues,
        "Number of expected transport fields is incorrect");
 
    // Accessor to "name1" transport field.
    auto transportField_name1() -> decltype(std::get<TransportFieldIdx_name1>(Base::transportFields()))
    {
        return std::get<TransportFieldIdx_name1>(Base::transportFields());
    }
 
    // Accessor to "name1" field.
    auto transportField_name1() const -> decltype(std::get<TransportFieldIdx_name1>(Base::transportFields()))
    {
        return std::get<TransportFieldIdx_name1>(Base::transportFields());
    }
 
    // Accessor to "name2" field.
    auto transportField_name2() -> decltype(std::get<TransportFieldIdx_name2>(Base::transportFields()))
    {
        return std::get<TransportFieldIdx_name2>(Base::transportFields());
    }
 
    // Accessor to "name2" field.
    auto transportField_name2() const -> decltype(std::get<TransportFieldIdx_name2>(Base::transportFields()))
    {
        return std::get<TransportFieldIdx_name2>(Base::transportFields());
    }
 
    // Accessor to "name3" field.
    auto transportField_name3() -> decltype(std::get<TransportFieldIdx_name3>(Base::transportFields()))
    {
        return std::get<TransportFieldIdx_name3>(Base::transportFields());
    }
 
    // Accessor to "name3" field.
    auto transportField_name3() const -> decltype(std::get<FieldIdx_name3>(Base::transportFields()))
    {
        return std::get<FieldIdx_name3>(Base::transportFields());
    }
 
    // Redefinition of the transport field types:
    using TransportField_name1 = TransportField1;
    using TransportField_name2 = TransportField2;
    using TransportField_name3 = TransportField3;
};

NOTE, that provided names name1, name2, and name3 have found their way to the following definitions:

• TransportFieldIdx enum. The names are prefixed with TransportFieldIdx_. The TransportFieldIdx_nameOfValues value is automatically added at the end.
• Accessor functions prefixed with transportField_*
• Types of fields prefixed with TransportField_*

As the result, the fields can be accessed using TransportFieldIdx enum

void handle(Message1& msg)
{
    auto& transportFields = msg.transportFields();
    auto& field1 = std::get<Message1::TransportFieldIdx_name1>(transportFields);
    auto& field2 = std::get<Message1::TransportFieldIdx_name2>(transportFields);
    auto& field3 = std::get<Message1::TransportFieldIdx_name3>(transportFields);
 
    auto value1 = field1.value();
    auto value2 = field2.value();
    auto value3 = field3.value();
}

or using accessor functions:

void handle(Message1& msg)
{
    auto value1 = transportField_name1().value();
    auto value2 = transportField_name2().value();
    auto value3 = transportField_name3().value();
}

Parameters

[in]

...

List of fields' names.

Precondition

Requires (re)definition of the message base class as inner Base member type.

See also

COMMS_MSG_TRANSPORT_FIELDS_ACCESS()

Note

Defined in "comms/Message.h"

operator!=()

template<typename TMessage1 , typename TMessage2 , typename... TOptions>

bool operator!= ( const MessageBase< TMessage1, TOptions... > &  msg1, const MessageBase< TMessage2, TOptions... > &  msg2  )

related

Message object inequality comparison operator.

Messages are considered not equal if any their fields are considered inequal.

operator==()

template<typename TMessage1 , typename TMessage2 , typename... TOptions>

bool operator== ( const MessageBase< TMessage1, TOptions... > &  msg1, const MessageBase< TMessage2, TOptions... > &  msg2  )

related

Message object equality comparison operator.

Messages are considered equal if all their fields are considered equal

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

• include/comms/GenericMessage.h