#include <memorystream.h>

Detailed Description

Implements a stream class which writes to and reads from system RAM.

Memory streams provide memory mapping for fast direct read/write access.

Copyright: (C) 2006 Radon Labs GmbH (C) 2013-2020 Individual contributors, see AUTHORS file

Inherited by Http::HttpNzStream, Http::HttpStream, and IO::EmbeddedMemoryStream.

Public Member Functions
	MemoryStream ()
	constructor

virtual	~MemoryStream ()
	destructor

virtual bool	CanRead () const
	memory streams support reading

virtual bool	CanWrite () const
	memory streams support writing

virtual bool	CanSeek () const
	memory streams support seeking

virtual bool	CanBeMapped () const
	memory streams are mappable

virtual void	SetSize (Size s)
	set new size of the stream in bytes

virtual Size	GetSize () const
	get the size of the stream in bytes

virtual Position	GetPosition () const
	get the current position of the read/write cursor

virtual bool	Open ()
	open the stream

virtual void	Close ()
	close the stream

virtual void	Write (const void *ptr, Size numBytes)
	directly write to the stream

virtual Size	Read (void *ptr, Size numBytes)
	directly read from the stream

virtual void	Seek (Offset offset, SeekOrigin origin)
	seek in stream

virtual bool	Eof () const
	return true if end-of-stream reached

virtual void *	Map ()
	map for direct memory-access

virtual void *	MemoryMap ()
	map for direct memory-access

virtual void	Unmap ()
	unmap a mapped stream

void *	GetRawPointer () const
	get a direct "raw" pointer to the data

Public Member Functions inherited from IO::Stream
	Stream ()
	constructor

virtual	~Stream ()
	destructor

void	SetURI (const URI &u)
	set stream location as URI

const URI &	GetURI () const
	get stream URI

void	SetAccessMode (AccessMode m)
	set the access mode of the stream (default is ReadAccess)

AccessMode	GetAccessMode () const
	get the access mode of the stream

void	SetAccessPattern (AccessPattern p)
	set the prefered access pattern (default is Sequential)

AccessPattern	GetAccessPattern () const
	get the prefered access pattern

void	SetMediaType (const MediaType &t)
	set optional media type of stream content

const MediaType &	GetMediaType () const
	get optional media type

bool	IsOpen () const
	return true if currently open

virtual void	Flush ()
	flush unsaved data

virtual void	MemoryUnmap ()
	unmap memory stream

bool	IsMapped () const
	return true if stream is currently mapped to memory

Public Member Functions inherited from Core::RefCounted
	RefCounted ()
	constructor

int	GetRefCount () const
	get the current refcount

void	AddRef ()
	increment refcount by one

void	Release ()
	decrement refcount and destroy object if refcount is zero

bool	IsInstanceOf (const Rtti &rtti) const
	return true if this object is instance of given class

bool	IsInstanceOf (const Util::String &className) const
	return true if this object is instance of given class by string

bool	IsInstanceOf (const Util::FourCC &classFourCC) const
	return true if this object is instance of given class by fourcc

bool	IsA (const Rtti &rtti) const
	return true if this object is instance of given class, or a derived class

bool	IsA (const Util::String &rttiName) const
	return true if this object is instance of given class, or a derived class, by string

bool	IsA (const Util::FourCC &rttiFourCC) const
	return true if this object is instance of given class, or a derived class, by fourcc

const Util::String &	GetClassName () const
	get the class name

Util::FourCC	GetClassFourCC () const
	get the class FourCC code

Protected Member Functions
void	Realloc (Size s)
	re-allocate the memory buffer

bool	HasRoom (Size numBytes) const
	return true if there's enough space for n more bytes

void	MakeRoom (Size numBytes)
	make room for at least n more bytes

Protected Member Functions inherited from Core::RefCounted
virtual	~RefCounted ()
	destructor (called when refcount reaches zero)

Protected Attributes
Size	capacity

Size	size

Position	position

unsigned char *	buffer

Protected Attributes inherited from IO::Stream
URI	uri

AccessMode	accessMode

AccessPattern	accessPattern

bool	isOpen

bool	isMapped

MediaType	mediaType

Static Protected Attributes
static const Size	InitialSize = 256

Private Member Functions
	__DeclareClass (MemoryStream)

Additional Inherited Members
Public Types inherited from IO::Stream
enum	AccessMode { ReadAccess , WriteAccess , AppendAccess , ReadWriteAccess }
	access modes More...

enum	AccessPattern { Random , Sequential }
	access prefered pattern More...

enum	SeekOrigin { Begin , Current , End }
	seek origins More...

typedef int64_t	Position
	typedefs

typedef int64_t	Offset

typedef int64_t	Size

Static Public Member Functions inherited from Core::RefCounted
static void	DumpRefCountingLeaks ()
	dump refcounting leaks, call at end of application (NEBULA_DEBUG builds only!)

Constructor & Destructor Documentation

◆ MemoryStream()

IO::MemoryStream::MemoryStream ( )

constructor

◆ ~MemoryStream()

IO::MemoryStream::~MemoryStream ( )

virtual

destructor

Member Function Documentation

◆ __DeclareClass()

IO::MemoryStream::__DeclareClass ( MemoryStream )

private

◆ CanBeMapped()

bool IO::MemoryStream::CanBeMapped ( ) const

virtual

memory streams are mappable

Reimplemented from IO::Stream.

◆ CanRead()

bool IO::MemoryStream::CanRead ( ) const

virtual

memory streams support reading

Reimplemented from IO::Stream.

◆ CanSeek()

bool IO::MemoryStream::CanSeek ( ) const

virtual

memory streams support seeking

Reimplemented from IO::Stream.

◆ CanWrite()

bool IO::MemoryStream::CanWrite ( ) const

virtual

memory streams support writing

Reimplemented from IO::Stream.

Reimplemented in IO::EmbeddedMemoryStream.

◆ Close()

void IO::MemoryStream::Close ( )

virtual

close the stream

Close the stream.

The contents of the stream will remain intact until destruction of the object, so that the same data may be accessed or modified during a later session.

Reimplemented from IO::Stream.

◆ Eof()

bool IO::MemoryStream::Eof ( ) const

virtual

return true if end-of-stream reached

Reimplemented from IO::Stream.

◆ GetPosition()

Stream::Position IO::MemoryStream::GetPosition ( ) const

virtual

get the current position of the read/write cursor

Reimplemented from IO::Stream.

◆ GetRawPointer()

void * IO::MemoryStream::GetRawPointer ( ) const

get a direct "raw" pointer to the data

Get a direct pointer to the raw data.

This is a convenience method and only works for memory streams. NOTE: writing new data to the stream may/will result in an invalid pointer, don't keep the returned pointer around between writes!

◆ GetSize()

Stream::Size IO::MemoryStream::GetSize ( ) const

virtual

get the size of the stream in bytes

Reimplemented from IO::Stream.

◆ HasRoom()

bool IO::MemoryStream::HasRoom ( Size numBytes ) const

protected

return true if there's enough space for n more bytes

◆ MakeRoom()

void IO::MemoryStream::MakeRoom ( Size numBytes )

protected

make room for at least n more bytes

This method makes room for at least N more bytes.

The actually allocated memory buffer will be greater then that. This operation involves a copy of existing data.

◆ Map()

void * IO::MemoryStream::Map ( )

virtual

map for direct memory-access

Map the stream for direct memory access.

This is much faster then reading/writing, but less flexible. A mapped stream cannot grow, instead the allowed memory range is determined by GetSize(). The read/writer must take special care to not read or write past the memory buffer boundaries!

Reimplemented from IO::Stream.

◆ MemoryMap()

void * IO::MemoryStream::MemoryMap ( )

virtual

map for direct memory-access

Reimplemented from IO::Stream.

◆ Open()

bool IO::MemoryStream::Open ( )

virtual

open the stream

Open the stream for reading or writing.

The stream may already contain data if it has been opened/closed before.

Reimplemented from IO::Stream.

Reimplemented in Http::HttpNzStream, Http::HttpStream, and IO::EmbeddedMemoryStream.

◆ Read()

Stream::Size IO::MemoryStream::Read	(	void *	ptr,
		Size	numBytes )

virtual

directly read from the stream

Reimplemented from IO::Stream.

◆ Realloc()

void IO::MemoryStream::Realloc ( Size newCapacity )

protected

re-allocate the memory buffer

This (re-)allocates the memory buffer to a new size.

If the new size is smaller then the existing size, the buffer contents will be clipped.

◆ Seek()

void IO::MemoryStream::Seek	(	Offset	offset,
		SeekOrigin	origin )

virtual

seek in stream

Reimplemented from IO::Stream.

◆ SetSize()

void IO::MemoryStream::SetSize ( Size s )

virtual

set new size of the stream in bytes

Reimplemented from IO::Stream.

◆ Unmap()

void IO::MemoryStream::Unmap ( )

virtual

unmap a mapped stream

Unmap a memory-mapped stream.

Reimplemented from IO::Stream.

◆ Write()

void IO::MemoryStream::Write	(	const void *	ptr,
		Size	numBytes )

virtual

directly write to the stream

Reimplemented from IO::Stream.

Member Data Documentation

◆ buffer

unsigned char* IO::MemoryStream::buffer

protected

◆ capacity

Size IO::MemoryStream::capacity

protected

◆ InitialSize

const Size IO::MemoryStream::InitialSize = 256

staticprotected

◆ position

Position IO::MemoryStream::position

protected

◆ size

Size IO::MemoryStream::size

protected

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

/github/workspace/code/foundation/io/memorystream.h
/github/workspace/code/foundation/io/memorystream.cc

Detailed Description

Public Member Functions

Protected Member Functions

Protected Attributes

Static Protected Attributes

Private Member Functions

Additional Inherited Members

Constructor & Destructor Documentation

◆ MemoryStream()

◆ ~MemoryStream()

Member Function Documentation

◆ __DeclareClass()

◆ CanBeMapped()

◆ CanRead()

◆ CanSeek()

◆ CanWrite()

◆ Close()

◆ Eof()

◆ GetPosition()

◆ GetRawPointer()

◆ GetSize()

◆ HasRoom()

◆ MakeRoom()

◆ Map()

◆ MemoryMap()

◆ Open()

◆ Read()

◆ Realloc()

◆ Seek()

◆ SetSize()

◆ Unmap()

◆ Write()

Member Data Documentation

◆ buffer

◆ capacity

◆ InitialSize

◆ position

◆ size