A file system that allows overlaying one AbstractFileSystem on top of another. More...

#include "llvm/Support/VirtualFileSystem.h"

Inheritance diagram for llvm::vfs::OverlayFileSystem:

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Collaboration diagram for llvm::vfs::OverlayFileSystem:

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Public Types
using	iterator = FileSystemList::reverse_iterator

using	const_iterator = FileSystemList::const_reverse_iterator

using	reverse_iterator = FileSystemList::iterator

using	const_reverse_iterator = FileSystemList::const_iterator

Public Member Functions
	OverlayFileSystem (IntrusiveRefCntPtr< FileSystem > Base)

void	pushOverlay (IntrusiveRefCntPtr< FileSystem > FS)
	Pushes a file system on top of the stack. More...

llvm::ErrorOr< Status >	status (const Twine &Path) override
	Get the status of the entry at `Path`, if one exists. More...

llvm::ErrorOr< std::unique_ptr< File > >	openFileForRead (const Twine &Path) override
	Get a `File` object for the file at `Path`, if one exists. More...

directory_iterator	dir_begin (const Twine &Dir, std::error_code &EC) override
	Get a directory_iterator for `Dir`. More...

llvm::ErrorOr< std::string >	getCurrentWorkingDirectory () const override
	Get the working directory of this file system. More...

std::error_code	setCurrentWorkingDirectory (const Twine &Path) override
	Set the working directory. More...

std::error_code	isLocal (const Twine &Path, bool &Result) override
	Is the file mounted on a local filesystem? More...

std::error_code	getRealPath (const Twine &Path, SmallVectorImpl< char > &Output) const override
	Gets real path of `Path` e.g. More...

iterator	overlays_begin ()
	Get an iterator pointing to the most recently added file system. More...

const_iterator	overlays_begin () const

iterator	overlays_end ()
	Get an iterator pointing one-past the least recently added file system. More...

const_iterator	overlays_end () const

reverse_iterator	overlays_rbegin ()
	Get an iterator pointing to the least recently added file system. More...

const_reverse_iterator	overlays_rbegin () const

reverse_iterator	overlays_rend ()
	Get an iterator pointing one-past the most recently added file system. More...

const_reverse_iterator	overlays_rend () const

Public Member Functions inherited from llvm::vfs::FileSystem
virtual	~FileSystem ()

llvm::ErrorOr< std::unique_ptr< llvm::MemoryBuffer > >	getBufferForFile (const Twine &Name, int64_t FileSize=-1, bool RequiresNullTerminator=true, bool IsVolatile=false)
	This is a convenience method that opens a file, gets its content and then closes the file. More...

bool	exists (const Twine &Path)
	Check whether a file exists. Provided for convenience. More...

virtual std::error_code	makeAbsolute (SmallVectorImpl< char > &Path) const
	Make Path an absolute path. More...

Public Member Functions inherited from llvm::ThreadSafeRefCountedBase< FileSystem >
void	Retain () const

void	Release () const

Additional Inherited Members
Protected Member Functions inherited from llvm::ThreadSafeRefCountedBase< FileSystem >
	ThreadSafeRefCountedBase ()=default

	ThreadSafeRefCountedBase (const ThreadSafeRefCountedBase &)

ThreadSafeRefCountedBase &	operator= (const ThreadSafeRefCountedBase &)=delete

	~ThreadSafeRefCountedBase ()

Detailed Description

A file system that allows overlaying one AbstractFileSystem on top of another.

Consists of a stack of >=1 FileSystem objects, which are treated as being one merged file system. When there is a directory that exists in more than one file system, the OverlayFileSystem contains a directory containing the union of their contents. The attributes (permissions, etc.) of the top-most (most recently added) directory are used. When there is a file that exists in more than one file system, the file in the top-most file system overrides the other(s).

Definition at line 322 of file VirtualFileSystem.h.

Member Typedef Documentation

◆ const_iterator

using llvm::vfs::OverlayFileSystem::const_iterator = FileSystemList::const_reverse_iterator

Definition at line 346 of file VirtualFileSystem.h.

◆ const_reverse_iterator

using llvm::vfs::OverlayFileSystem::const_reverse_iterator = FileSystemList::const_iterator

Definition at line 348 of file VirtualFileSystem.h.

◆ iterator

using llvm::vfs::OverlayFileSystem::iterator = FileSystemList::reverse_iterator

Definition at line 345 of file VirtualFileSystem.h.

◆ reverse_iterator

using llvm::vfs::OverlayFileSystem::reverse_iterator = FileSystemList::iterator

Definition at line 347 of file VirtualFileSystem.h.

Constructor & Destructor Documentation

◆ OverlayFileSystem()

OverlayFileSystem::OverlayFileSystem ( IntrusiveRefCntPtr< FileSystem > Base )

Definition at line 389 of file VirtualFileSystem.cpp.

References move.

Member Function Documentation

◆ dir_begin()

directory_iterator OverlayFileSystem::dir_begin	(	const Twine &	Dir,
		std::error_code &	EC
	)

overridevirtual

Get a directory_iterator for Dir.

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

Implements llvm::vfs::FileSystem.

Definition at line 536 of file VirtualFileSystem.cpp.

References llvm::Twine::str().

◆ getCurrentWorkingDirectory()

llvm::ErrorOr< std::string > OverlayFileSystem::getCurrentWorkingDirectory ( ) const

overridevirtual

Get the working directory of this file system.

Implements llvm::vfs::FileSystem.

Definition at line 422 of file VirtualFileSystem.cpp.

Referenced by pushOverlay().

◆ getRealPath()

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

overridevirtual

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 from llvm::vfs::FileSystem.

Definition at line 443 of file VirtualFileSystem.cpp.

References llvm::X86AS::FS, and llvm::no_such_file_or_directory.

◆ isLocal()

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

overridevirtual

Is the file mounted on a local filesystem?

Reimplemented from llvm::vfs::FileSystem.

Definition at line 435 of file VirtualFileSystem.cpp.

References llvm::X86AS::FS, and llvm::no_such_file_or_directory.

◆ openFileForRead()

ErrorOr< std::unique_ptr< File > > OverlayFileSystem::openFileForRead ( const Twine & Path )

overridevirtual

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

Implements llvm::vfs::FileSystem.

Definition at line 411 of file VirtualFileSystem.cpp.

References E, I, llvm::make_error_code(), llvm::no_such_file_or_directory, overlays_begin(), and overlays_end().

◆ overlays_begin() [1/2]

iterator llvm::vfs::OverlayFileSystem::overlays_begin ( )

inline

Get an iterator pointing to the most recently added file system.

Definition at line 351 of file VirtualFileSystem.h.

Referenced by openFileForRead(), and status().

◆ overlays_begin() [2/2]

const_iterator llvm::vfs::OverlayFileSystem::overlays_begin ( ) const

inline

Definition at line 352 of file VirtualFileSystem.h.

◆ overlays_end() [1/2]

iterator llvm::vfs::OverlayFileSystem::overlays_end ( )

inline

Get an iterator pointing one-past the least recently added file system.

Definition at line 355 of file VirtualFileSystem.h.

Referenced by openFileForRead(), and status().

◆ overlays_end() [2/2]

const_iterator llvm::vfs::OverlayFileSystem::overlays_end ( ) const

inline

Definition at line 356 of file VirtualFileSystem.h.

◆ overlays_rbegin() [1/2]

reverse_iterator llvm::vfs::OverlayFileSystem::overlays_rbegin ( )

inline

Get an iterator pointing to the least recently added file system.

Definition at line 359 of file VirtualFileSystem.h.

◆ overlays_rbegin() [2/2]

const_reverse_iterator llvm::vfs::OverlayFileSystem::overlays_rbegin ( ) const

inline

Definition at line 360 of file VirtualFileSystem.h.

◆ overlays_rend() [1/2]

reverse_iterator llvm::vfs::OverlayFileSystem::overlays_rend ( )

inline

Get an iterator pointing one-past the most recently added file system.

Definition at line 363 of file VirtualFileSystem.h.

◆ overlays_rend() [2/2]

const_reverse_iterator llvm::vfs::OverlayFileSystem::overlays_rend ( ) const

inline

Definition at line 364 of file VirtualFileSystem.h.

◆ pushOverlay()

void OverlayFileSystem::pushOverlay ( IntrusiveRefCntPtr< FileSystem > FS )

Pushes a file system on top of the stack.

Definition at line 393 of file VirtualFileSystem.cpp.

References llvm::X86AS::FS, get, and getCurrentWorkingDirectory().

◆ setCurrentWorkingDirectory()

std::error_code OverlayFileSystem::setCurrentWorkingDirectory ( const Twine & Path )

overridevirtual

Set the working directory.

This will affect all following operations on this file system and may propagate down for nested file systems.

Implements llvm::vfs::FileSystem.

Definition at line 428 of file VirtualFileSystem.cpp.

References llvm::X86AS::FS.

◆ status()

ErrorOr< Status > OverlayFileSystem::status ( const Twine & Path )

overridevirtual

Get the status of the entry at Path, if one exists.

Implements llvm::vfs::FileSystem.

Definition at line 400 of file VirtualFileSystem.cpp.

References E, I, llvm::make_error_code(), llvm::no_such_file_or_directory, overlays_begin(), and overlays_end().

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

include/llvm/Support/VirtualFileSystem.h
lib/Support/VirtualFileSystem.cpp

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ const_iterator

◆ const_reverse_iterator

◆ iterator

◆ reverse_iterator

Constructor & Destructor Documentation

◆ OverlayFileSystem()

Member Function Documentation

◆ dir_begin()

◆ getCurrentWorkingDirectory()

◆ getRealPath()

◆ isLocal()

◆ openFileForRead()

◆ overlays_begin() [1/2]

◆ overlays_begin() [2/2]

◆ overlays_end() [1/2]

◆ overlays_end() [2/2]

◆ overlays_rbegin() [1/2]

◆ overlays_rbegin() [2/2]

◆ overlays_rend() [1/2]

◆ overlays_rend() [2/2]

◆ pushOverlay()

◆ setCurrentWorkingDirectory()

◆ status()