File system keeping last stream created by linked file system (OSD_FileSystem::DefaultFileSystem() by default) to be reused for opening a stream with the same URL. Note that as file is kept in opened state, application will need destroying this object to ensure all files being closed. This interface could be handy in context of reading numerous objects pointing to the same file (at different offset). Make sure to create a dedicated OSD_CachedFileSystem for each working thread to avoid data races. More...

#include <OSD_CachedFileSystem.hxx>

Inheritance diagram for OSD_CachedFileSystem:

[legend]

Data Structures
struct	OSD_CachedStream

Public Member Functions
	OSD_CachedFileSystem (const occ::handle< OSD_FileSystem > &theLinkedFileSystem=occ::handle< OSD_FileSystem >())
	Constructor.
const occ::handle< OSD_FileSystem > &	LinkedFileSystem () const
	Return linked file system; initialized with OSD_FileSystem::DefaultFileSystem() by default.
void	SetLinkedFileSystem (const occ::handle< OSD_FileSystem > &theLinkedFileSystem)
	Sets linked file system.
bool	IsSupportedPath (const TCollection_AsciiString &theUrl) const override
	Returns TRUE if URL defines a supported protocol.
bool	IsOpenIStream (const std::shared_ptr< std::istream > &theStream) const override
	Returns TRUE if current input stream is opened for reading operations.
bool	IsOpenOStream (const std::shared_ptr< std::ostream > &theStream) const override
	Returns TRUE if current output stream is opened for writing operations.
std::shared_ptr< std::istream >	OpenIStream (const TCollection_AsciiString &theUrl, const std::ios_base::openmode theParams, const int64_t theOffset, const std::shared_ptr< std::istream > &theOldStream) override
	Opens stream for specified file URL for reading operations or returns previously created stream pointing to the same URL.
std::shared_ptr< std::ostream >	OpenOStream (const TCollection_AsciiString &theUrl, const std::ios_base::openmode theMode) override
	Opens stream for specified file URL for writing operations (std::ostream) by calling parent's method.
std::shared_ptr< std::streambuf >	OpenStreamBuffer (const TCollection_AsciiString &theUrl, const std::ios_base::openmode theMode, const int64_t theOffset=0, int64_t *theOutBufSize=nullptr) override
	Opens stream buffer for specified file URL.
Public Member Functions inherited from OSD_FileSystem
	OSD_FileSystem ()
	Constructor.
	~OSD_FileSystem () override
	Destructor.
Public Member Functions inherited from Standard_Transient
	Standard_Transient ()
	Empty constructor.
	Standard_Transient (const Standard_Transient &)
	Copy constructor – does nothing.
Standard_Transient &	operator= (const Standard_Transient &)
	Assignment operator, needed to avoid copying reference counter.
virtual	~Standard_Transient ()=default
	Destructor must be virtual.
virtual const opencascade::handle< Standard_Type > &	DynamicType () const
	Returns a type descriptor about this object.
bool	IsInstance (const opencascade::handle< Standard_Type > &theType) const
	Returns a true value if this is an instance of Type.
bool	IsInstance (const char *const theTypeName) const
	Returns a true value if this is an instance of TypeName.
bool	IsKind (const opencascade::handle< Standard_Type > &theType) const
	Returns true if this is an instance of Type or an instance of any class that inherits from Type. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
bool	IsKind (const char *const theTypeName) const
	Returns true if this is an instance of TypeName or an instance of any class that inherits from TypeName. Note that multiple inheritance is not supported by OCCT RTTI mechanism.
Standard_Transient *	This () const
	Returns non-const pointer to this object (like const_cast). For protection against creating handle to objects allocated in stack or call from constructor, it will raise exception Standard_ProgramError if reference counter is zero.
int	GetRefCount () const noexcept
	Get the reference counter of this object.
void	IncrementRefCounter () noexcept
	Increments the reference counter of this object. Uses relaxed memory ordering since incrementing only requires atomicity, not synchronization with other memory operations.
int	DecrementRefCounter () noexcept
	Decrements the reference counter of this object; returns the decremented value. Uses release ordering for the decrement to ensure all writes to the object are visible before the count reaches zero. An acquire fence is added only when the count reaches zero, ensuring proper synchronization before deletion. This is more efficient than using acq_rel for every decrement.
virtual void	Delete () const
	Memory deallocator for transient classes.

Protected Attributes
OSD_CachedStream	myStream
	active cached stream
occ::handle< OSD_FileSystem >	myLinkedFS
	linked file system to open files

Additional Inherited Members
typedef void	base_type
	Returns a type descriptor about this object.
Static Public Member Functions inherited from OSD_FileSystem
static const occ::handle< OSD_FileSystem > &	DefaultFileSystem ()
	Returns a global file system, which a selector between registered file systems (OSD_FileSystemSelector).
static void	AddDefaultProtocol (const occ::handle< OSD_FileSystem > &theFileSystem, bool theIsPreferred=false)
	Registers file system within the global file system selector returned by OSD_FileSystem::DefaultFileSystem(). Note that registering protocols is not thread-safe operation and expected to be done once at application startup.
static void	RemoveDefaultProtocol (const occ::handle< OSD_FileSystem > &theFileSystem)
	Unregisters file system within the global file system selector returned by OSD_FileSystem::DefaultFileSystem().
static constexpr const char *	get_type_name ()
	Returns a type descriptor about this object.
static const opencascade::handle< Standard_Type > &	get_type_descriptor ()
	Returns type descriptor of Standard_Transient class.

Detailed Description

File system keeping last stream created by linked file system (OSD_FileSystem::DefaultFileSystem() by default) to be reused for opening a stream with the same URL. Note that as file is kept in opened state, application will need destroying this object to ensure all files being closed. This interface could be handy in context of reading numerous objects pointing to the same file (at different offset). Make sure to create a dedicated OSD_CachedFileSystem for each working thread to avoid data races.

Constructor & Destructor Documentation

◆ OSD_CachedFileSystem()

OSD_CachedFileSystem::OSD_CachedFileSystem ( const occ::handle< OSD_FileSystem > & theLinkedFileSystem = occ::handle< OSD_FileSystem >() )

Constructor.

Member Function Documentation

◆ IsOpenIStream()

bool OSD_CachedFileSystem::IsOpenIStream ( const std::shared_ptr< std::istream > & theStream ) const

overridevirtual

Returns TRUE if current input stream is opened for reading operations.

Implements OSD_FileSystem.

◆ IsOpenOStream()

bool OSD_CachedFileSystem::IsOpenOStream ( const std::shared_ptr< std::ostream > & theStream ) const

overridevirtual

Returns TRUE if current output stream is opened for writing operations.

Implements OSD_FileSystem.

◆ IsSupportedPath()

bool OSD_CachedFileSystem::IsSupportedPath ( const TCollection_AsciiString & theUrl ) const

overridevirtual

Returns TRUE if URL defines a supported protocol.

Implements OSD_FileSystem.

◆ LinkedFileSystem()

const occ::handle< OSD_FileSystem > & OSD_CachedFileSystem::LinkedFileSystem ( ) const

inline

Return linked file system; initialized with OSD_FileSystem::DefaultFileSystem() by default.

◆ OpenIStream()

std::shared_ptr< std::istream > OSD_CachedFileSystem::OpenIStream	(	const TCollection_AsciiString &	theUrl,
		const std::ios_base::openmode	theParams,
		const int64_t	theOffset,
		const std::shared_ptr< std::istream > &	theOldStream )

overridevirtual

Opens stream for specified file URL for reading operations or returns previously created stream pointing to the same URL.

Reimplemented from OSD_FileSystem.

◆ OpenOStream()

std::shared_ptr< std::ostream > OSD_CachedFileSystem::OpenOStream	(	const TCollection_AsciiString &	theUrl,
		const std::ios_base::openmode	theMode )

overridevirtual

Opens stream for specified file URL for writing operations (std::ostream) by calling parent's method.

Reimplemented from OSD_FileSystem.

◆ OpenStreamBuffer()

std::shared_ptr< std::streambuf > OSD_CachedFileSystem::OpenStreamBuffer	(	const TCollection_AsciiString &	theUrl,
		const std::ios_base::openmode	theMode,
		const int64_t	theOffset = 0,
		int64_t *	theOutBufSize = nullptr )

overridevirtual

Opens stream buffer for specified file URL.

Implements OSD_FileSystem.

◆ SetLinkedFileSystem()

void OSD_CachedFileSystem::SetLinkedFileSystem ( const occ::handle< OSD_FileSystem > & theLinkedFileSystem )

inline

Sets linked file system.

Field Documentation

◆ myLinkedFS

occ::handle<OSD_FileSystem> OSD_CachedFileSystem::myLinkedFS

protected

linked file system to open files

◆ myStream

OSD_CachedStream OSD_CachedFileSystem::myStream

protected

active cached stream

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

OSD_CachedFileSystem.hxx

Data Structures

Public Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ OSD_CachedFileSystem()

Member Function Documentation

◆ IsOpenIStream()

◆ IsOpenOStream()

◆ IsSupportedPath()

◆ LinkedFileSystem()

◆ OpenIStream()

◆ OpenOStream()

◆ OpenStreamBuffer()

◆ SetLinkedFileSystem()

Field Documentation

◆ myLinkedFS

◆ myStream