The virtual file system interface. More...

#include "llvm/Support/VirtualFileSystem.h"

Inheritance diagram for llvm::vfs::FileSystem:

Public Types
enum class	PrintType { Summary , Contents , RecursiveContents }
using	VisitCallbackTy = llvm::function_ref<void(FileSystem &)>

Public Member Functions
virtual	~FileSystem ()
virtual llvm::ErrorOr< Status >	status (const Twine &Path)=0
	Get the status of the entry at `Path`, if one exists.
virtual llvm::ErrorOr< std::unique_ptr< File > >	openFileForRead (const Twine &Path)=0
	Get a `File` object for the text file at `Path`, if one exists.
virtual llvm::ErrorOr< std::unique_ptr< File > >	openFileForReadBinary (const Twine &Path)
	Get a `File` object for the binary file at `Path`, if one exists.
llvm::ErrorOr< std::unique_ptr< llvm::MemoryBuffer > >	getBufferForFile (const Twine &Name, int64_t FileSize=-1, bool RequiresNullTerminator=true, bool IsVolatile=false, bool IsText=true)
	This is a convenience method that opens a file, gets its content and then closes the file.
virtual directory_iterator	dir_begin (const Twine &Dir, std::error_code &EC)=0
	Get a directory_iterator for `Dir`.
virtual std::error_code	setCurrentWorkingDirectory (const Twine &Path)=0
	Set the working directory.
virtual llvm::ErrorOr< std::string >	getCurrentWorkingDirectory () const =0
	Get the working directory of this file system.
virtual std::error_code	getRealPath (const Twine &Path, SmallVectorImpl< char > &Output)
	Gets real path of `Path` e.g.
virtual bool	exists (const Twine &Path)
	Check whether `Path` exists.
virtual std::error_code	isLocal (const Twine &Path, bool &Result)
	Is the file mounted on a local filesystem?
virtual std::error_code	makeAbsolute (SmallVectorImpl< char > &Path) const
	Make Path an absolute path.
llvm::ErrorOr< bool >	equivalent (const Twine &A, const Twine &B)
void	print (raw_ostream &OS, PrintType Type=PrintType::Contents, unsigned IndentLevel=0) const
virtual void	visitChildFileSystems (VisitCallbackTy Callback)
void	visit (VisitCallbackTy Callback)
LLVM_DUMP_METHOD void	dump () const
Public Member Functions inherited from llvm::ThreadSafeRefCountedBase< FileSystem >
unsigned	UseCount () const
void	Retain () const
void	Release () const
Public Member Functions inherited from llvm::RTTIExtends< FileSystem, RTTIRoot >
const void *	dynamicClassID () const override
bool	isA () const
	Check whether this instance is a subclass of QueryT.
Public Member Functions inherited from llvm::RTTIRoot
virtual	~RTTIRoot ()=default
virtual bool	isA (const void *const ClassID) const
	Returns true if this class's ID matches the given class ID.

Static Public Attributes
static const char	ID = 0

Protected Member Functions
virtual void	printImpl (raw_ostream &OS, PrintType Type, unsigned IndentLevel) const
void	printIndent (raw_ostream &OS, unsigned IndentLevel) const
Protected Member Functions inherited from llvm::ThreadSafeRefCountedBase< FileSystem >
	ThreadSafeRefCountedBase ()=default
ThreadSafeRefCountedBase &	operator= (const ThreadSafeRefCountedBase &)=delete
	~ThreadSafeRefCountedBase ()

Additional Inherited Members
Static Public Member Functions inherited from llvm::RTTIExtends< FileSystem, RTTIRoot >
static const void *	classID ()
static bool	classof (const T *R)
Static Public Member Functions inherited from llvm::RTTIRoot
static const void *	classID ()
	Returns the class ID for this type.

Detailed Description

The virtual file system interface.

Definition at line 267 of file VirtualFileSystem.h.

Member Typedef Documentation

◆ VisitCallbackTy

using llvm::vfs::FileSystem::VisitCallbackTy = llvm::function_ref<void(FileSystem &)>

Definition at line 347 of file VirtualFileSystem.h.

Member Enumeration Documentation

◆ PrintType

enum class llvm::vfs::FileSystem::PrintType

strong

Enumerator
Summary
Contents
RecursiveContents

Definition at line 341 of file VirtualFileSystem.h.

Constructor & Destructor Documentation

◆ ~FileSystem()

FileSystem::~FileSystem ( )

virtualdefault

Member Function Documentation

◆ dir_begin()

virtual directory_iterator llvm::vfs::FileSystem::dir_begin	(	const Twine &	Dir,
		std::error_code &	EC )

pure virtual

Get a directory_iterator for Dir.

Note: The 'end' iterator is directory_iterator().

Implemented in llvm::FileCollectorFileSystem, and llvm::vfs::RedirectingFileSystem.

Referenced by getHighestNumericTupleInDirectory().

◆ dump()

void FileSystem::dump ( ) const

Definition at line 165 of file VirtualFileSystem.cpp.

References llvm::dbgs(), print(), and RecursiveContents.

◆ equivalent()

llvm::ErrorOr< bool > FileSystem::equivalent	(	const Twine &	A,
		const Twine &	B )

Returns: true if A and B represent the same file, or an error or false if they do not.

Definition at line 154 of file VirtualFileSystem.cpp.

References A(), B(), and status().

Referenced by getCurrentWorkingDirectory().

◆ exists()

bool FileSystem::exists ( const Twine & Path )

virtual

Check whether Path exists.

By default this uses status(), but filesystems may provide a more efficient implementation if available.

Reimplemented in llvm::vfs::RedirectingFileSystem.

Definition at line 149 of file VirtualFileSystem.cpp.

References llvm::vfs::Status::exists(), and status().

Referenced by llvm::findVCToolChainViaEnvironment(), getCurrentWorkingDirectory(), llvm::getWindowsSDKDir(), and llvm::useUniversalCRT().

◆ getBufferForFile()

ErrorOr< std::unique_ptr< MemoryBuffer > > FileSystem::getBufferForFile	(	const Twine &	Name,
		int64_t	FileSize = -1,
		bool	RequiresNullTerminator = true,
		bool	IsVolatile = false,
		bool	IsText = true )

This is a convenience method that opens a file, gets its content and then closes the file.

The IsText parameter is used to distinguish whether the file should be opened as a binary or text file.

Definition at line 118 of file VirtualFileSystem.cpp.

References F, openFileForRead(), and openFileForReadBinary().

Referenced by llvm::SpecialCaseList::createInternal().

◆ getCurrentWorkingDirectory()

virtual llvm::ErrorOr< std::string > llvm::vfs::FileSystem::getCurrentWorkingDirectory ( ) const

pure virtual

Get the working directory of this file system.

Implemented in llvm::FileCollectorFileSystem, and llvm::vfs::RedirectingFileSystem.

References A(), B(), equivalent(), exists(), getRealPath(), and isLocal().

Referenced by makeAbsolute().

◆ getRealPath()

std::error_code FileSystem::getRealPath	(	const Twine &	Path,
		SmallVectorImpl< char > &	Output )

virtual

Gets real path of Path e.g.

collapse all . and .. patterns, resolve symlinks. For real file system, this uses llvm::sys::fs::real_path. This returns errc::operation_not_permitted if not implemented by subclass.

Reimplemented in llvm::FileCollectorFileSystem, and llvm::vfs::RedirectingFileSystem.

Definition at line 140 of file VirtualFileSystem.cpp.

References llvm::operation_not_permitted.

Referenced by getCurrentWorkingDirectory().

◆ isLocal()

std::error_code FileSystem::isLocal	(	const Twine &	Path,
		bool &	Result )

virtual

Is the file mounted on a local filesystem?

Reimplemented in llvm::FileCollectorFileSystem, and llvm::vfs::RedirectingFileSystem.

Definition at line 145 of file VirtualFileSystem.cpp.

References llvm::operation_not_permitted.

Referenced by getCurrentWorkingDirectory().

◆ makeAbsolute()

std::error_code FileSystem::makeAbsolute ( SmallVectorImpl< char > & Path ) const

virtual

Make Path an absolute path.

Makes Path absolute using the current directory if it is not already. An empty Path will result in the current directory.

/absolute/path => /absolute/path relative/../path => <current-directory>/relative/../path

Parameters

Path	A path that is modified to be an absolute path.

Returns: success if path has been made absolute, otherwise a platform-specific error_code.

Reimplemented in llvm::vfs::RedirectingFileSystem.

Definition at line 128 of file VirtualFileSystem.cpp.

References getCurrentWorkingDirectory(), llvm::sys::path::is_absolute(), and llvm::sys::fs::make_absolute().

◆ openFileForRead()

virtual llvm::ErrorOr< std::unique_ptr< File > > llvm::vfs::FileSystem::openFileForRead ( const Twine & Path )

pure virtual

Get a File object for the text file at Path, if one exists.

Implemented in llvm::FileCollectorFileSystem, and llvm::vfs::RedirectingFileSystem.

Referenced by getBufferForFile(), and openFileForReadBinary().

◆ openFileForReadBinary()

virtual llvm::ErrorOr< std::unique_ptr< File > > llvm::vfs::FileSystem::openFileForReadBinary ( const Twine & Path )

inlinevirtual

Get a File object for the binary file at Path, if one exists.

Some non-ascii based file systems perform encoding conversions when reading as a text file, and this function should be used if a file's bytes should be read as-is. On most filesystems, this is the same behaviour as openFileForRead.

Definition at line 286 of file VirtualFileSystem.h.

References openFileForRead().

Referenced by getBufferForFile().