Detailed Description

This base class is used to provide a unified interface to files,memory buffers,..Please see the derived classes.

This class is largely inspired by Borland VCL "TStream" class.

Apart of the "VCL like" methods, operators ">>" and "<<" have been defined so that simple types (int,bool,char,float,char *,std::string,...) can be directly written and read to and from any CStream easily. Please, it is recomendable to read CSerializable documentation also.

See also: CFileStream, CMemoryStream,CSerializable

Definition at line 36 of file CStream.h.

#include <mrpt/utils/CStream.h>

Inheritance diagram for mrpt::utils::CStream:

[legend]

Public Types
enum	TSeekOrigin { sFromBeginning = 0, sFromCurrent = 1, sFromEnd = 2 }
	Used in CStream::Seek. More...

Public Member Functions
	CStream ()

virtual	~CStream ()

size_t	ReadBuffer (void *Buffer, size_t Count)
	Reads a block of bytes from the stream into Buffer. More...

template<typename T >
size_t	ReadBufferFixEndianness (T *ptr, size_t ElementCount)
	Reads a sequence of elemental datatypes, taking care of reordering their bytes from the MRPT stream standard (little endianness) to the format of the running architecture. More...

virtual size_t	ReadBufferImmediate (void *Buffer, size_t Count)
	Reads a block of bytes from the stream into Buffer, and returns the amound of bytes actually read, without waiting for more extra bytes to arrive (just those already enqued in the stream). More...

void	WriteBuffer (const void *Buffer, size_t Count)
	Writes a block of bytes to the stream from Buffer. More...

template<typename T >
void	WriteBufferFixEndianness (const T *ptr, size_t ElementCount)
	Writes a sequence of elemental datatypes, taking care of reordering their bytes from the running architecture to MRPT stream standard (little endianness). More...

size_t	CopyFrom (CStream *Source, size_t Count)
	Copies a specified number of bytes from one stream to another. More...

virtual uint64_t	Seek (uint64_t Offset, CStream::TSeekOrigin Origin=sFromBeginning)=0
	Introduces a pure virtual method for moving to a specified position in the streamed resource. More...

virtual uint64_t	getTotalBytesCount ()=0
	Returns the total amount of bytes in the stream. More...

virtual uint64_t	getPosition ()=0
	Method for getting the current cursor position, where 0 is the first byte and TotalBytesCount-1 the last one. More...

void	WriteObject (const CSerializable *o)
	Writes an object to the stream. More...

CSerializablePtr	ReadObject ()
	Reads an object from stream, its class determined at runtime, and returns a smart pointer to the object. More...

void	ReadObject (CSerializable *existingObj)
	Reads an object from stream, where its class must be the same as the supplied object, where the loaded object will be stored in. More...

CStream &	operator<< (const CSerializablePtr &pObj)
	Write an object to a stream in the binary MRPT format. More...

CStream &	operator<< (const CSerializable &obj)
	Write an object to a stream in the binary MRPT format. More...

CStream &	operator>> (CSerializablePtr &pObj)

CStream &	operator>> (CSerializable &obj)

virtual int	printf (const char *fmt,...) MRPT_printf_format_check(2
	Writes a string to the stream in a textual form. More...

template<typename T >
virtual int void	printf_vector (const char *fmt, const std::vector< T > &V)
	Prints a vector in the format [A,B,C,...] using CStream::printf, and the fmt string for each vector element. More...

void	sendMessage (const utils::CMessage &msg)
	Send a message to the device. More...

bool	receiveMessage (utils::CMessage &msg)
	Tries to receive a message from the device. More...

bool	getline (std::string &out_str)
	Reads from the stream until a ' ' character is found ('' characters are ignored). More...

Protected Member Functions
virtual size_t	Read (void *Buffer, size_t Count)=0
	Introduces a pure virtual method responsible for reading from the stream. More...

virtual size_t	Write (const void *Buffer, size_t Count)=0
	Introduces a pure virtual method responsible for writing to the stream. More...

Member Enumeration Documentation

◆ TSeekOrigin

enum mrpt::utils::CStream::TSeekOrigin

Used in CStream::Seek.

Enumerator
sFromBeginning
sFromCurrent
sFromEnd

Definition at line 41 of file CStream.h.

Constructor & Destructor Documentation

◆ CStream()

mrpt::utils::CStream::CStream ( )

inline

Definition at line 60 of file CStream.h.

◆ ~CStream()

virtual mrpt::utils::CStream::~CStream ( )

virtual

Member Function Documentation

◆ CopyFrom()

size_t mrpt::utils::CStream::CopyFrom	(	CStream *	Source,
		size_t	Count
	)

Copies a specified number of bytes from one stream to another.

◆ getline()

bool mrpt::utils::CStream::getline ( std::string & out_str )

Reads from the stream until a '
' character is found ('' characters are ignored).

Returns: false on EOF or any other read error.

◆ getPosition()

virtual uint64_t mrpt::utils::CStream::getPosition ( )

pure virtual

Method for getting the current cursor position, where 0 is the first byte and TotalBytesCount-1 the last one.

Implemented in mrpt::hwdrivers::CSerialPort, mrpt::hwdrivers::CInterfaceFTDI, mrpt::utils::CClientTCPSocket, mrpt::utils::CFileStream, mrpt::synch::CPipeBaseEndPoint, mrpt::utils::CMemoryStream, mrpt::utils::CFileOutputStream, mrpt::utils::CFileInputStream, mrpt::utils::CFileGZInputStream, and mrpt::utils::CStdOutStream.

◆ getTotalBytesCount()

virtual uint64_t mrpt::utils::CStream::getTotalBytesCount ( )

pure virtual

Returns the total amount of bytes in the stream.

Implemented in mrpt::hwdrivers::CSerialPort, mrpt::hwdrivers::CInterfaceFTDI, mrpt::utils::CClientTCPSocket, mrpt::utils::CFileStream, mrpt::synch::CPipeBaseEndPoint, mrpt::utils::CMemoryStream, mrpt::utils::CFileOutputStream, mrpt::utils::CFileInputStream, mrpt::utils::CFileGZInputStream, and mrpt::utils::CStdOutStream.

◆ operator<<() [1/2]

CStream& mrpt::utils::CStream::operator<< ( const CSerializablePtr & pObj )

Write an object to a stream in the binary MRPT format.

◆ operator<<() [2/2]

CStream& mrpt::utils::CStream::operator<< ( const CSerializable & obj )

Write an object to a stream in the binary MRPT format.

◆ operator>>() [1/2]

CStream& mrpt::utils::CStream::operator>> ( CSerializablePtr & pObj )

◆ operator>>() [2/2]

CStream& mrpt::utils::CStream::operator>> ( CSerializable & obj )

◆ printf()

virtual int mrpt::utils::CStream::printf	(	const char *	fmt,
			...
	)

virtual

Writes a string to the stream in a textual form.

See also: CStdOutStream

Referenced by mrpt::bayes::TKF_options::dumpToTextStream(), mrpt::slam::COctoMapBase< OCTREE, OCTREE_NODE >::TInsertionOptions::dumpToTextStream(), and mrpt::slam::COctoMapBase< OCTREE, OCTREE_NODE >::TLikelihoodOptions::dumpToTextStream().

◆ printf_vector()

template<typename T >

virtual int void mrpt::utils::CStream::printf_vector	(	const char *	fmt,
		const std::vector< T > &	V
	)

inline

Prints a vector in the format [A,B,C,...] using CStream::printf, and the fmt string for each vector element.

Definition at line 200 of file CStream.h.

◆ Read()

virtual size_t mrpt::utils::CStream::Read	(	void *	Buffer,
		size_t	Count
	)

protectedpure virtual

Introduces a pure virtual method responsible for reading from the stream.

Implemented in mrpt::hwdrivers::CInterfaceFTDI, mrpt::hwdrivers::CSerialPort, mrpt::synch::CPipeBaseEndPoint, mrpt::utils::CClientTCPSocket, mrpt::utils::CFileStream, mrpt::utils::CFileGZInputStream, mrpt::utils::CStdOutStream, mrpt::utils::CMemoryStream, mrpt::utils::CFileInputStream, and mrpt::utils::CFileOutputStream.

◆ ReadBuffer()

size_t mrpt::utils::CStream::ReadBuffer	(	void *	Buffer,
		size_t	Count
	)

Reads a block of bytes from the stream into Buffer.

Exceptions

std::exception On any error, or if ZERO bytes are read.

Returns: The amound of bytes actually read.

Note: This method is endianness-dependent.

See also: ReadBufferImmediate ; Important, see: ReadBufferFixEndianness,

◆ ReadBufferFixEndianness()

template<typename T >

size_t mrpt::utils::CStream::ReadBufferFixEndianness	(	T *	ptr,
		size_t	ElementCount
	)

inline

Reads a sequence of elemental datatypes, taking care of reordering their bytes from the MRPT stream standard (little endianness) to the format of the running architecture.

Parameters

ElementCount	The number of elements (not bytes) to read.
ptr	A pointer to the first output element in an array (or std::vector<>, etc...).

Returns: The amound of bytes (not elements) actually read (under error situations, the last element may be invalid if the data stream abruptly ends). Example of usage:
uint32_t N;
s >> N;
vector<float> vec(N);
if (N)
s.ReadBufferFixEndianness<float>(&vec[0],N);

Exceptions

std::exception On any error, or if ZERO bytes are read.

See also: ReadBufferFixEndianness, ReadBuffer

Definition at line 90 of file CStream.h.

References mrpt::mrpt::utils::reverseBytesInPlace().

Referenced by mrpt::math::operator>>().

◆ ReadBufferImmediate()

virtual size_t mrpt::utils::CStream::ReadBufferImmediate	(	void *	Buffer,
		size_t	Count
	)

inlinevirtual

Reads a block of bytes from the stream into Buffer, and returns the amound of bytes actually read, without waiting for more extra bytes to arrive (just those already enqued in the stream).

Note that this method will fallback to ReadBuffer() in most CStream classes but in some hardware-related classes.

Exceptions

std::exception On any error, or if ZERO bytes are read.

Reimplemented in mrpt::hwdrivers::CInterfaceFTDI.

Definition at line 108 of file CStream.h.

◆ ReadObject() [1/2]

CSerializablePtr mrpt::utils::CStream::ReadObject ( )

Reads an object from stream, its class determined at runtime, and returns a smart pointer to the object.

Exceptions

std::exception	On I/O error or undefined class.
mrpt::utils::CExceptionEOF	On an End-Of-File condition found at a correct place: an EOF that abruptly finishes in the middle of one object raises a plain std::exception instead.

Referenced by mrpt::math::operator>>().

◆ ReadObject() [2/2]

void mrpt::utils::CStream::ReadObject ( CSerializable * existingObj )

Reads an object from stream, where its class must be the same as the supplied object, where the loaded object will be stored in.

Exceptions

std::exception	On I/O error or different class found.
mrpt::utils::CExceptionEOF	On an End-Of-File condition found at a correct place: an EOF that abruptly finishes in the middle of one object raises a plain std::exception instead.

◆ receiveMessage()

bool mrpt::utils::CStream::receiveMessage ( utils::CMessage & msg )

Tries to receive a message from the device.

Exceptions

std::exception On communication errors

Returns: True if successful, false if there is no new data from the device (but communications seem to work fine)

See also: The frame format is described in sendMessage()

◆ Seek()

virtual uint64_t mrpt::utils::CStream::Seek	(	uint64_t	Offset,
		CStream::TSeekOrigin	Origin = `sFromBeginning`
	)

pure virtual

Introduces a pure virtual method for moving to a specified position in the streamed resource.

he Origin parameter indicates how to interpret the Offset parameter. Origin should be one of the following values:

sFromBeginning (Default) Offset is from the beginning of the resource. Seek moves to the position Offset. Offset must be >= 0.
sFromCurrent Offset is from the current position in the resource. Seek moves to Position + Offset.
sFromEnd Offset is from the end of the resource. Offset must be <= 0 to indicate a number of bytes before the end of the file.
Returns
Seek returns the new value of the Position property.

Implemented in mrpt::utils::CClientTCPSocket, mrpt::utils::CFileStream, mrpt::utils::CFileGZInputStream, mrpt::utils::CMemoryStream, mrpt::utils::CFileOutputStream, mrpt::utils::CFileInputStream, and mrpt::utils::CStdOutStream.

◆ sendMessage()

void mrpt::utils::CStream::sendMessage ( const utils::CMessage & msg )

Send a message to the device.

Note that only the low byte from the "type" field will be used.

For frames of size < 255 the frame format is an array of bytes in this order:

<START_FLAG> <HEADER> <LENGTH> <BODY> <END_FLAG>
       <START_FLAG>    = 0x69
       <HEADER>                = A header byte
       <LENGHT>                = Number of bytes of BODY
       <BODY>                  = N x bytes
       <END_FLAG>              = 0X96
Total length   =       <LENGTH> + 4

For frames of size > 255 the frame format is an array of bytes in this order:

<START_FLAG> <HEADER> <HIBYTE(LENGTH)> <LOBYTE(LENGTH)> <BODY> <END_FLAG>
       <START_FLAG>    = 0x79
       <HEADER>                = A header byte
       <LENGHT>                = Number of bytes of BODY
       <BODY>                  = N x bytes
       <END_FLAG>              = 0X96
Total length   =       <LENGTH> + 5

Exceptions

std::exception On communication errors

◆ Write()

virtual size_t mrpt::utils::CStream::Write	(	const void *	Buffer,
		size_t	Count
	)

protectedpure virtual

Introduces a pure virtual method responsible for writing to the stream.

Write attempts to write up to Count bytes to Buffer, and returns the number of bytes actually written.

Implemented in mrpt::hwdrivers::CInterfaceFTDI, mrpt::hwdrivers::CSerialPort, mrpt::synch::CPipeBaseEndPoint, mrpt::utils::CClientTCPSocket, mrpt::utils::CFileStream, mrpt::utils::CFileGZInputStream, mrpt::utils::CStdOutStream, mrpt::utils::CMemoryStream, mrpt::utils::CFileInputStream, and mrpt::utils::CFileOutputStream.

◆ WriteBuffer()

void mrpt::utils::CStream::WriteBuffer	(	const void *	Buffer,
		size_t	Count
	)

Writes a block of bytes to the stream from Buffer.

Exceptions

std::exception On any error

See also: Important, see: WriteBufferFixEndianness

Note: This method is endianness-dependent.

◆ WriteBufferFixEndianness()

template<typename T >

void mrpt::utils::CStream::WriteBufferFixEndianness	(	const T *	ptr,
		size_t	ElementCount
	)

inline

Writes a sequence of elemental datatypes, taking care of reordering their bytes from the running architecture to MRPT stream standard (little endianness).

Parameters

ElementCount	The number of elements (not bytes) to write.
ptr	A pointer to the first input element in an array (or std::vector<>, etc...). Example of usage: vector<float> vec = ... uint32_t N = vec.size(); s << N if (N) s.WriteBufferFixEndianness<float>(&vec[0],N);

Exceptions

std::exception On any error

See also: WriteBuffer

Definition at line 134 of file CStream.h.

◆ WriteObject()

void mrpt::utils::CStream::WriteObject ( const CSerializable * o )

Writes an object to the stream.

Detailed Description

Public Types

Public Member Functions

Protected Member Functions

Member Enumeration Documentation

◆ TSeekOrigin

Constructor & Destructor Documentation

◆ CStream()

◆ ~CStream()

Member Function Documentation

◆ CopyFrom()

◆ getline()

◆ getPosition()

◆ getTotalBytesCount()

◆ operator<<() [1/2]

◆ operator<<() [2/2]

◆ operator>>() [1/2]

◆ operator>>() [2/2]

◆ printf()

◆ printf_vector()

◆ Read()

◆ ReadBuffer()

◆ ReadBufferFixEndianness()

◆ ReadBufferImmediate()

◆ ReadObject() [1/2]

◆ ReadObject() [2/2]

◆ receiveMessage()

◆ Seek()

◆ sendMessage()

◆ Write()

◆ WriteBuffer()

◆ WriteBufferFixEndianness()

◆ WriteObject()