#include <Symlink.h>

Inheritance diagram for Symlink:

Collaboration diagram for Symlink:

Public Member Functions
	Symlink ()

	Symlink (const Symlink &file)

	Symlink (const String &name, Time::Timestamp accessedTime, Time::Timestamp modifiedTime, Time::Timestamp creationTime, uintptr_t inode, class Filesystem pFs, size_t size, File pParent)

virtual	~Symlink ()

virtual bool	isSymlink ()

virtual int	followLink (char *pBuffer, size_t bufLen)

virtual File *	followLinkRetained (Directory::ChildLease &result)

virtual bool	isPathLink () const

virtual bool	followPath (FilesystemPathRef &)

Public Member Functions inherited from File
	File ()

	File (const String &name, Time::Timestamp accessedTime, Time::Timestamp modifiedTime, Time::Timestamp creationTime, uintptr_t inode, class Filesystem pFs, size_t size, File pParent)

virtual	~File ()

virtual uint64_t	read (uint64_t location, uint64_t size, uintptr_t buffer, bool bCanBlock=true) final

size_t	readCached (uint64_t location, size_t size, uintptr_t buffer, bool(*prepare)(uintptr_t, size_t)=nullptr)

virtual uint64_t	write (uint64_t location, uint64_t size, uintptr_t buffer, bool bCanBlock=true) final

uint64_t	append (uint64_t size, uintptr_t buffer, uint64_t &location, bool bCanBlock=true)

WriteGuard	lockWrites ()

virtual physical_uintptr_t	getPhysicalPage (size_t offset)

virtual bool	isDirectPhysicalMapping () const

size_t	physicalMappingFlags () const

virtual void	returnPhysicalPage (size_t offset)

virtual bool	tryBeginMappingRelease ()

void	endMappingRelease ()

bool	syncAndReturnPhysicalPage (size_t offset, bool async)

virtual bool	sync ()

bool	syncRange (size_t offset, size_t length)

virtual bool	sync (size_t offset, bool async)

virtual bool	syncPages (const uint64_t *offsets, size_t count)

Time::Timestamp	getCreationTime ()

void	setCreationTime (Time::Timestamp t)

Time::Timestamp	getAccessedTime ()

void	setAccessedTime (Time::Timestamp t)

Time::Timestamp	getModifiedTime ()

void	setModifiedTime (Time::Timestamp t)

void	setTimes (Time::Timestamp accessed, Time::Timestamp modified, bool changeAccessed, bool changeModified)

virtual Attributes	getAttributes () const

virtual XattrStatus	getExtendedAttribute (const StringView &name, void *buffer, size_t capacity, size_t &required)

virtual XattrStatus	listExtendedAttributes (void *buffer, size_t capacity, size_t &required)

virtual XattrStatus	setExtendedAttribute (const StringView &name, const void *value, size_t length, unsigned flags)

virtual XattrStatus	removeExtendedAttribute (const StringView &name)

virtual bool	prepareSharedMapping (size_t offset, size_t length)

String	getName () const

void	getName (String &s) const

virtual void	getFullPath (String &result, bool bWithMount=true)

virtual String	getFullPath (bool bWithMount=true)

virtual void	truncate ()

bool	resize (size_t size)

virtual size_t	getSize ()

void	setSize (size_t sz)

virtual bool	isDirectory ()

virtual bool	isBlockDevice () const

virtual uint64_t	deviceNumber () const

virtual bool	isPipe () const

virtual bool	isFifo () const

virtual bool	isSocket () const

virtual bool	isSeekable () const

bool	supportsRegularFileOperations ()

virtual bool	isCharacterDevice () const

virtual bool	isConsole () const

virtual uint64_t	maximumFileSize () const

virtual bool	allowMapping (bool shared, bool writeRequested, bool &mayWrite)

bool	acquireMappingUse (bool executable, bool sharedWrite)

void	releaseMappingUse (bool executable, bool sharedWrite)

uintptr_t	getInode () const

virtual void	setInode (uintptr_t inode)

virtual uintptr_t	futexIdentity ()

Filesystem *	getFilesystem () const

void	setFilesystem (Filesystem *pFs)

virtual void	fileAttributeChanged ()

void	publishEvent (FileEventMask mask, const StringView &name=StringView(), bool targetIsDirectory=false)

virtual FileHandleStatus	subscribeInodeEvents (FileEventMask mask, const SharedPointer< FileEventObserver > &observer, FileEventSubscription &subscription)

virtual void	finishInodeRetirement ()

virtual void	increaseRefCount (bool bIsWriter)

virtual void	decreaseRefCount (bool bIsWriter)

virtual bool	retainVfsReference ()

virtual void	releaseVfsReference ()

virtual bool	isStableVfsRoot () const

void	setPermissions (uint32_t perms)

uint32_t	getPermissions () const

bool	setOwnership (size_t uid, size_t gid, bool changeUid, bool changeGid)

void	setUid (size_t uid)

size_t	getUid () const

void	setGid (size_t gid)

size_t	getGid () const

File *	getParent () const

void	getNamespace (ParentLease &parent, String &name) const

virtual int	select (bool bWriting=false, int timeout=0)

virtual ReadyMask	queryReady (bool reading, bool writing)

virtual bool	supportsReadinessNotifications () const

void	monitor (Thread pThread, Event pEvent)

void	cullMonitorTargets (Thread *pThread)

void	cullMonitorTargets (Event *pEvent)

virtual bool	supports (const size_t command) const

virtual int	command (const size_t command, void *buffer)

virtual size_t	getBlockSize () const

void	markPageExternallyWritable (size_t offset)

size_t	populateRange (size_t offset, size_t length)

void	enableDirect ()

void	disableDirect ()

virtual void	preallocate (size_t expectedSize, bool zero=true)

bool	allocateRange (size_t offset, size_t length, bool keepSize=false)

virtual File *	open ()

virtual File *	openForDescriptor (RetainedFile &owner)

Public Member Functions inherited from ReadinessSource
MUST_USE_RESULT bool	subscribeReadiness (ReadyMask interest, const SharedPointer< ReadinessObserver > &observer, ReadinessSubscription &subscription)

virtual ReadinessGenerations	readinessGenerations ()

Public Member Functions inherited from FileEventSource
MUST_USE_RESULT bool	subscribeFileEvents (FileEventMask interest, const SharedPointer< FileEventObserver > &observer, FileEventSubscription &subscription)

Static Public Member Functions
static Symlink *	fromFile (File *pF)

Protected Member Functions
void	initialise (bool bForce=false)

virtual bool	isBytewise () const

Protected Member Functions inherited from File
bool	tryAcquireFilesystemOperation (OperationBarrier::Lease &operation) const

virtual void	updateAttributes (const Attributes &attributes, uint32_t mask)

virtual bool	changeOwnership (size_t uid, size_t gid, bool changeUid, bool changeGid)

virtual bool	allowPhysicalPage () const

virtual bool	prepareWrite (uint64_t location, uint64_t size)

virtual bool	allowResize (size_t oldSize, size_t newSize)

virtual bool	prepareShrink (const ShrinkContext &context, UniquePointer< PreparedShrink > &prepared)

virtual bool	resizeFile (size_t size)

virtual bool	allocateFileRange (size_t offset, size_t length)

virtual Mutex &	writeSerializationLock ()

virtual Mutex &	dataMutationLock ()

virtual size_t &	physicalPageLoans ()

bool	clearDataCache ()

virtual uint64_t	readBytewise (uint64_t location, uint64_t size, uintptr_t buffer, bool bCanBlock=true)

virtual uint64_t	writeBytewise (uint64_t location, uint64_t size, uintptr_t buffer, bool bCanBlock=true)

virtual uintptr_t	readBlock (uint64_t location)

virtual bool	readPage (uint64_t location, uintptr_t destination)

virtual bool	readPages (ReadPage *pages, size_t count)

virtual void	writeBlock (uint64_t location, uintptr_t addr)

virtual void	writeBlocks (uint64_t location, uintptr_t addr, size_t length)

virtual void	extend (size_t newSize)

virtual void	extend (size_t newSize, uint64_t location, uint64_t size)

virtual void	publishInodeEvent (const FileEvent &event)

void	dataChanged ()

void	getFilesystemLabel (HugeStaticString &s)

void	enableFillCacheWriteback ()

void	shutdownFillCacheWriteback ()

bool	syncFillCache (size_t offset, bool async, bool &present)

virtual bool	useFillCache () const

virtual MUST_USE_RESULT bool	pinBlock (uint64_t location)

virtual MUST_USE_RESULT uintptr_t	acquireCachedBlock (uint64_t location, bool retryChanged)

virtual void	unpinBlock (uint64_t location)

void	evict (uint64_t location)

void	setPermissionsOnly (uint32_t perms)

void	setUidOnly (size_t uid)

void	setGidOnly (size_t gid)

void	retainDetachedParent ()

void	moveNamespace (const String &name, File *parent)

bool	snapshotNamespace (ParentLease &parent, String &name, FileEventMask interest) const

virtual CacheState &	cacheState ()

void	setPhysicalMappingFlags (size_t flags)

Protected Member Functions inherited from ReadinessSource
void	notifyReadiness (ReadyMask mask)

void	closeReadiness (ReadyMask mask=ReadyInvalid\|ReadyHangup)

Protected Member Functions inherited from FileEventSource
bool	hasFileEventObservers (FileEventMask mask) const

void	notifyFileEvent (const FileEvent &event)

void	notifyFinalFileEvent (const FileEvent &event)

void	beginFinalFileEvent (const FileEvent &event)

void	drainFileEvents ()

void	closeFileEvents ()

Static Protected Member Functions
static File *	retainTarget (File *target, Directory::ChildLease &result)

Static Protected Member Functions inherited from File
static bool	writeCallback (CacheConstants::CallbackCause cause, uintptr_t loc, uintptr_t page, void *meta)

static bool	fillCacheCallback (CacheConstants::CallbackCause cause, uintptr_t loc, uintptr_t page, void *meta)

Static Protected Member Functions inherited from FileEventSource
static bool	anyFileEventObservers ()

Protected Attributes
String	m_sTarget

Mutex	m_TargetLock

Protected Attributes inherited from File
String	m_Name

Time::Timestamp	m_AccessedTime

Time::Timestamp	m_ModifiedTime

Time::Timestamp	m_CreationTime

uintptr_t	m_Inode

uintptr_t	m_FutexIdentity = 0

class Filesystem *	m_pFilesystem

size_t	m_Size

File *	m_pParent

Mutex	m_MetadataLock

File *	m_pDetachedParent

bool	m_bDetachedParentHandled

size_t	m_nWriters

size_t	m_nReaders

size_t	m_Uid

size_t	m_Gid

uint32_t	m_Permissions

CacheState	m_CacheState

bool	m_bDirect

Mutex	m_WriteLock

Mutex	m_DataMutationLock

size_t	m_PhysicalPageLoans = 0

size_t	m_PhysicalMappingFlags = 0

Mutex	m_Lock

List< MonitorTarget * >	m_MonitorTargets

Private Member Functions
Symlink &	operator= (const Symlink &)

Friends
class	Filesystem

Additional Inherited Members
Public Types inherited from File
enum	AttributeMask : uint32_t { AccessTime = 1U << 0 , ModifyTime = 1U << 1 , ChangeTime = 1U << 2 , Owner = 1U << 3 , Group = 1U << 4 , Permissions = 1U << 5 }

Static Public Attributes inherited from File
static constexpr size_t	MaxReadPages = 32

Detailed Description

A symbolic link node.

Definition at line 33 of file Symlink.h.

Constructor & Destructor Documentation

◆ Symlink() [1/3]

Symlink::Symlink ( )

Constructor, creates an invalid file.

Definition at line 27 of file Symlink.cc.

◆ Symlink() [2/3]

Symlink::Symlink ( const Symlink & file )

Copy constructors are hidden - unused!

◆ Symlink() [3/3]

Symlink::Symlink	(	const String &	name,
		Time::Timestamp	accessedTime,
		Time::Timestamp	modifiedTime,
		Time::Timestamp	creationTime,
		uintptr_t	inode,
		class Filesystem *	pFs,
		size_t	size,
		File *	pParent
	)

Constructor, should be called only by a Filesystem.

Definition at line 29 of file Symlink.cc.

◆ ~Symlink()

Symlink::~Symlink ( )

virtual

Destructor - doesn't do anything.

Definition at line 36 of file Symlink.cc.

Member Function Documentation

◆ followLink()

int Symlink::followLink	(	char *	pBuffer,
		size_t	bufLen
	)

virtual

Reads the contents of the file as a symbolic link and returns the contents in the given buffer.

Returns: Number of bytes copied.

Definition at line 90 of file Symlink.cc.

References initialise(), and m_TargetLock.

◆ followLinkRetained()

File * Symlink::followLinkRetained ( Directory::ChildLease & result )

virtual

Follow the link while retaining the resolved target's VFS lifetime.

Definition at line 73 of file Symlink.cc.

References VFS::findRetained(), Filesystem::findRetained(), File::getNamespace(), initialise(), VFS::instance(), m_TargetLock, and String::view().

Referenced by Filesystem::findNode(), DynamicLinker::loadObject(), and DynamicLinker::loadProgram().

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◆ followPath()

virtual bool Symlink::followPath ( FilesystemPathRef & )

inlinevirtual

Definition at line 77 of file Symlink.h.

◆ fromFile()

static Symlink * Symlink::fromFile ( File * pF )

inlinestatic

Eases the pain of casting, and performs a sanity check.

Definition at line 38 of file Symlink.h.

References File::isSymlink().

Referenced by Filesystem::findNode(), DynamicLinker::loadObject(), and DynamicLinker::loadProgram().

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◆ initialise()

void Symlink::initialise ( bool bForce = false )

protected

Read the symlink target. Allows this to be done lazily.

Definition at line 47 of file Symlink.cc.

References File::read(), and String::rstrip().

Referenced by followLink(), followLinkRetained(), and FatSymlink::writeBytewise().

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◆ isBytewise()

bool Symlink::isBytewise ( ) const

protectedvirtual

Most Symlink objects will be bytewise, but for those that aren't they can override this

Reimplemented from File.

Definition at line 102 of file Symlink.cc.

◆ isPathLink()

virtual bool Symlink::isPathLink ( ) const

inlinevirtual

Descriptor links retain the OFD opening path; ordinary links return false.

Definition at line 74 of file Symlink.h.

◆ isSymlink()

virtual bool Symlink::isSymlink ( )

inlinevirtual

Returns true if the File is actually a symlink.

Reimplemented from File.

Definition at line 62 of file Symlink.h.

◆ retainTarget()

File * Symlink::retainTarget	(	File *	target,
		Directory::ChildLease &	result
	)

staticprotected

Retain an already tracked dynamic target without caching its identity.

Definition at line 38 of file Symlink.cc.

References VFS::instance().

Friends And Related Symbol Documentation

◆ Filesystem

friend class Filesystem

friend

Definition at line 34 of file Symlink.h.

Member Data Documentation

◆ m_sTarget

String Symlink::m_sTarget

protected

Definition at line 85 of file Symlink.h.

◆ m_TargetLock

Mutex Symlink::m_TargetLock

protected

Serialises lazy target loading.

Definition at line 88 of file Symlink.h.

Referenced by followLink(), followLinkRetained(), and FatSymlink::writeBytewise().

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

Public Member Functions

Static Public Member Functions

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Private Member Functions

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ Symlink() [1/3]

◆ Symlink() [2/3]

◆ Symlink() [3/3]

◆ ~Symlink()

Member Function Documentation

◆ followLink()

◆ followLinkRetained()

◆ followPath()

◆ fromFile()

◆ initialise()

◆ isBytewise()

◆ isPathLink()

◆ isSymlink()

◆ retainTarget()

Friends And Related Symbol Documentation

◆ Filesystem

Member Data Documentation

◆ m_sTarget

◆ m_TargetLock