class RedirectingFileSystem
Declaration
class RedirectingFileSystem : public FileSystem { /* full declaration omitted */ };
Description
A virtual file system parsed from a YAML file. Currently, this class allows creating virtual files and directories. Virtual files map to existing external files in \c ExternalFS, and virtual directories may either map to existing directories in \c ExternalFS or list their contents in the form of other virtual directories and/or files. The basic structure of the parsed file is: The roots may be absolute or relative. If relative they will be made absolute against the current working directory. All configuration options are optional. 'case-sensitive': <boolean , default=(true for Posix, false for Windows)> 'use-external-names': <boolean , default=true> 'overlay-relative': <boolean , default=false> 'fallthrough': <boolean , default=true, deprecated - use 'redirecting-with' instead> 'redirecting-with': <string , one of 'fallthrough', 'fallback', or 'redirect-only', default='fallthrough'> Virtual directories that list their contents are represented as The default attributes for such virtual directories are: When a path prefix matches such a directory, the next component in the path is matched against the entries in the 'contents' array. Re-mapped directories, on the other hand, are represented as /// and inherit their attributes from the external directory. When a path prefix matches such an entry, the unmatched components are appended to the 'external-contents' path, and the resulting path is looked up in the external file system instead. Re-mapped files are represented as Their attributes and file contents are determined by looking up the file at their 'external-contents' path in the external file system. For 'file', 'directory' and 'directory-remap' entries the 'name' field may contain multiple path components (e.g. /path/to/file). However, any directory in such a path that contains more than one child must be uniquely represented by a 'directory' entry. When the 'use-external-name' field is set, calls to \a vfs::File::status() give the external (remapped) filesystem name instead of the name the file was accessed by. This is an intentional leak through the \a RedirectingFileSystem abstraction layer. It enables clients to discover (and use) the external file location when communicating with users or tools that don't use the same VFS overlay. FIXME: 'use-external-name' causes behaviour that's inconsistent with how "real" filesystems behave. Maybe there should be a separate channel for this information.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:729
Inherits from: FileSystem
Member Variables
- private std::vector<std::unique_ptr<Entry>> Roots
- The root(s) of the virtual file system.
- private std::string WorkingDirectory
- The current working directory of the file system.
- private IntrusiveRefCntPtr<llvm::vfs::FileSystem> ExternalFS
- The file system to use for external references.
- private std::string ExternalContentsPrefixDir
- If IsRelativeOverlay is set, this represents the directory path that should be prefixed to each 'external-contents' entry when reading from YAML files.
- private bool CaseSensitive = is_style_posix(sys::path::Style::native)
- Currently, case-insensitive matching only works correctly with ASCII.
- private bool IsRelativeOverlay = false
- IsRelativeOverlay marks whether a ExternalContentsPrefixDir path must be prefixed in every 'external-contents' when reading from YAML files.
- private bool UseExternalNames = true
- Whether to use to use the value of 'external-contents' for the names of files. This global value is overridable on a per-file basis.
- private llvm::vfs::RedirectingFileSystem::RedirectKind Redirection = RedirectKind::Fallthrough
- Determines the lookups to perform, as well as their order. See\c RedirectKind for details.
Method Overview
- private RedirectingFileSystem(IntrusiveRefCntPtr<llvm::vfs::FileSystem> ExternalFS)
- public static std::unique_ptr<RedirectingFileSystem> create(ArrayRef<std::pair<std::string, std::string>> RemappedFiles, bool UseExternalNames, llvm::vfs::FileSystem & ExternalFS)
- public static std::unique_ptr<RedirectingFileSystem> create(std::unique_ptr<MemoryBuffer> Buffer, SourceMgr::DiagHandlerTy DiagHandler, llvm::StringRef YAMLFilePath, void * DiagContext, IntrusiveRefCntPtr<llvm::vfs::FileSystem> ExternalFS)
- public llvm::vfs::directory_iterator dir_begin(const llvm::Twine & Dir, std::error_code & EC)
- public llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const
- public llvm::StringRef getExternalContentsPrefixDir() const
- private ErrorOr<llvm::vfs::Status> getExternalStatus(const llvm::Twine & CanonicalPath, const llvm::Twine & OriginalPath) const
- public std::error_code getRealPath(const llvm::Twine & Path, SmallVectorImpl<char> & Output) const
- public std::vector<llvm::StringRef> getRoots() const
- public std::error_code isLocal(const llvm::Twine & Path, bool & Result)
- public ErrorOr<llvm::vfs::RedirectingFileSystem::LookupResult> lookupPath(llvm::StringRef Path) const
- private ErrorOr<llvm::vfs::RedirectingFileSystem::LookupResult> lookupPathImpl(llvm::sys::path::const_iterator Start, llvm::sys::path::const_iterator End, llvm::vfs::RedirectingFileSystem::Entry * From) const
- public std::error_code makeAbsolute(SmallVectorImpl<char> & Path) const
- private std::error_code makeCanonical(SmallVectorImpl<char> & Path) const
- public ErrorOr<std::unique_ptr<File>> openFileForRead(const llvm::Twine & Path)
- private bool pathComponentMatches(llvm::StringRef lhs, llvm::StringRef rhs) const
- public void printEntry(llvm::raw_ostream & OS, llvm::vfs::RedirectingFileSystem::Entry * E, unsigned int IndentLevel = 0) const
- protected void printImpl(llvm::raw_ostream & OS, llvm::vfs::FileSystem::PrintType Type, unsigned int IndentLevel) const
- public std::error_code setCurrentWorkingDirectory(const llvm::Twine & Path)
- public void setExternalContentsPrefixDir(llvm::StringRef PrefixDir)
- public void setFallthrough(bool Fallthrough)
- public void setRedirection(RedirectingFileSystem::RedirectKind Kind)
- public ErrorOr<llvm::vfs::Status> status(const llvm::Twine & Path)
- private ErrorOr<llvm::vfs::Status> status(const llvm::Twine & CanonicalPath, const llvm::Twine & OriginalPath, const llvm::vfs::RedirectingFileSystem::LookupResult & Result)
Inherited from FileSystem:
- public dir_begin
- public dump
- public exists
- public getBufferForFile
- public getCurrentWorkingDirectory
- public getRealPath
- public isLocal
- public makeAbsolute
- public openFileForRead
- public print
- protected printImpl
- protected printIndent
- public setCurrentWorkingDirectory
- public status
Methods
¶RedirectingFileSystem(
IntrusiveRefCntPtr<llvm::vfs::FileSystem>
ExternalFS)
RedirectingFileSystem(
IntrusiveRefCntPtr<llvm::vfs::FileSystem>
ExternalFS)
Description
@ }
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:939
Parameters
- IntrusiveRefCntPtr<llvm::vfs::FileSystem> ExternalFS
¶static std::unique_ptr<RedirectingFileSystem>
create(
ArrayRef<std::pair<std::string, std::string>>
RemappedFiles,
bool UseExternalNames,
llvm::vfs::FileSystem& ExternalFS)
static std::unique_ptr<RedirectingFileSystem>
create(
ArrayRef<std::pair<std::string, std::string>>
RemappedFiles,
bool UseExternalNames,
llvm::vfs::FileSystem& ExternalFS)
Description
Redirect each of the remapped files from first to second.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:968
Parameters
- ArrayRef<std::pair<std::string, std::string>> RemappedFiles
- bool UseExternalNames
- llvm::vfs::FileSystem& ExternalFS
¶static std::unique_ptr<RedirectingFileSystem>
create(std::unique_ptr<MemoryBuffer> Buffer,
SourceMgr::DiagHandlerTy DiagHandler,
llvm::StringRef YAMLFilePath,
void* DiagContext,
IntrusiveRefCntPtr<llvm::vfs::FileSystem>
ExternalFS)
static std::unique_ptr<RedirectingFileSystem>
create(std::unique_ptr<MemoryBuffer> Buffer,
SourceMgr::DiagHandlerTy DiagHandler,
llvm::StringRef YAMLFilePath,
void* DiagContext,
IntrusiveRefCntPtr<llvm::vfs::FileSystem>
ExternalFS)
Description
Parses \p Buffer, which is expected to be in YAML format and returns a virtual file system representing its contents.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:962
Parameters
- std::unique_ptr<MemoryBuffer> Buffer
- SourceMgr::DiagHandlerTy DiagHandler
- llvm::StringRef YAMLFilePath
- void* DiagContext
- IntrusiveRefCntPtr<llvm::vfs::FileSystem> ExternalFS
¶llvm::vfs::directory_iterator dir_begin(
const llvm::Twine& Dir,
std::error_code& EC)
llvm::vfs::directory_iterator dir_begin(
const llvm::Twine& Dir,
std::error_code& EC)
Description
Get a directory_iterator for \p Dir.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:985
Parameters
- const llvm::Twine& Dir
- std::error_code& EC
¶llvm::ErrorOr<std::string>
getCurrentWorkingDirectory() const
llvm::ErrorOr<std::string>
getCurrentWorkingDirectory() const
Description
Get the working directory of this file system.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:977
¶llvm::StringRef getExternalContentsPrefixDir()
const
llvm::StringRef getExternalContentsPrefixDir()
const
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:989
¶ErrorOr<llvm::vfs::Status> getExternalStatus(
const llvm::Twine& CanonicalPath,
const llvm::Twine& OriginalPath) const
ErrorOr<llvm::vfs::Status> getExternalStatus(
const llvm::Twine& CanonicalPath,
const llvm::Twine& OriginalPath) const
Description
Get the File status, or error, from the underlying external file system. This returns the status with the originally requested name, while looking up the entry using the canonical path.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:890
Parameters
- const llvm::Twine& CanonicalPath
- const llvm::Twine& OriginalPath
¶std::error_code getRealPath(
const llvm::Twine& Path,
SmallVectorImpl<char>& Output) const
std::error_code getRealPath(
const llvm::Twine& Path,
SmallVectorImpl<char>& Output) const
Description
Gets real path of \p 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.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:974
Parameters
- const llvm::Twine& Path
- SmallVectorImpl<char>& Output
¶std::vector<llvm::StringRef> getRoots() const
std::vector<llvm::StringRef> getRoots() const
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:997
¶std::error_code isLocal(const llvm::Twine& Path,
bool& Result)
std::error_code isLocal(const llvm::Twine& Path,
bool& Result)
Description
Is the file mounted on a local filesystem?
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:981
Parameters
- const llvm::Twine& Path
- bool& Result
¶ErrorOr<llvm::vfs::RedirectingFileSystem::
LookupResult>
lookupPath(llvm::StringRef Path) const
ErrorOr<llvm::vfs::RedirectingFileSystem::
LookupResult>
lookupPath(llvm::StringRef Path) const
Description
Looks up \p Path in \c Roots and returns a LookupResult giving the matched entry and, if the entry was a FileEntry or DirectoryRemapEntry, the path it redirects to in the external file system.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:957
Parameters
- llvm::StringRef Path
¶ErrorOr<llvm::vfs::RedirectingFileSystem::
LookupResult>
lookupPathImpl(
llvm::sys::path::const_iterator Start,
llvm::sys::path::const_iterator End,
llvm::vfs::RedirectingFileSystem::Entry* From)
const
ErrorOr<llvm::vfs::RedirectingFileSystem::
LookupResult>
lookupPathImpl(
llvm::sys::path::const_iterator Start,
llvm::sys::path::const_iterator End,
llvm::vfs::RedirectingFileSystem::Entry* From)
const
Description
Looks up the path [Start, End) in \p From, possibly recursing into the contents of \p From if it is a directory. Returns a LookupResult giving the matched entry and, if that entry is a FileEntry or DirectoryRemapEntry, the path it redirects to in the external file system.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:945
Parameters
- llvm::sys::path::const_iterator Start
- llvm::sys::path::const_iterator End
- llvm::vfs::RedirectingFileSystem::Entry* From
¶std::error_code makeAbsolute(
SmallVectorImpl<char>& Path) const
std::error_code makeAbsolute(
SmallVectorImpl<char>& Path) const
Description
Make \a Path an absolute path. Makes \a Path absolute using the current directory if it is not already. An empty \a Path will result in the current directory. /absolute/path => /absolute/path relative/../path => <current -directory>/relative/../path
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:983
Parameters
- SmallVectorImpl<char>& Path
- A path that is modified to be an absolute path.
Returns
success if \a path has been made absolute, otherwise a platform-specific error_code.
¶std::error_code makeCanonical(
SmallVectorImpl<char>& Path) const
std::error_code makeCanonical(
SmallVectorImpl<char>& Path) const
Description
Canonicalize path by removing ".", "..", "./", components. This is a VFS request, do not bother about symlinks in the path components but canonicalize in order to perform the correct entry search.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:885
Parameters
- SmallVectorImpl<char>& Path
¶ErrorOr<std::unique_ptr<File>> openFileForRead(
const llvm::Twine& Path)
ErrorOr<std::unique_ptr<File>> openFileForRead(
const llvm::Twine& Path)
Description
Get a \p File object for the file at \p Path, if one exists.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:972
Parameters
- const llvm::Twine& Path
¶bool pathComponentMatches(
llvm::StringRef lhs,
llvm::StringRef rhs) const
bool pathComponentMatches(
llvm::StringRef lhs,
llvm::StringRef rhs) const
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:898
Parameters
- llvm::StringRef lhs
- llvm::StringRef rhs
¶void printEntry(
llvm::raw_ostream& OS,
llvm::vfs::RedirectingFileSystem::Entry* E,
unsigned int IndentLevel = 0) const
void printEntry(
llvm::raw_ostream& OS,
llvm::vfs::RedirectingFileSystem::Entry* E,
unsigned int IndentLevel = 0) const
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:999
Parameters
- llvm::raw_ostream& OS
- llvm::vfs::RedirectingFileSystem::Entry* E
- unsigned int IndentLevel = 0
¶void printImpl(
llvm::raw_ostream& OS,
llvm::vfs::FileSystem::PrintType Type,
unsigned int IndentLevel) const
void printImpl(
llvm::raw_ostream& OS,
llvm::vfs::FileSystem::PrintType Type,
unsigned int IndentLevel) const
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:1002
Parameters
- llvm::raw_ostream& OS
- llvm::vfs::FileSystem::PrintType Type
- unsigned int IndentLevel
¶std::error_code setCurrentWorkingDirectory(
const llvm::Twine& Path)
std::error_code setCurrentWorkingDirectory(
const llvm::Twine& Path)
Description
Set the working directory. This will affect all following operations on this file system and may propagate down for nested file systems.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:979
Parameters
- const llvm::Twine& Path
¶void setExternalContentsPrefixDir(
llvm::StringRef PrefixDir)
void setExternalContentsPrefixDir(
llvm::StringRef PrefixDir)
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:987
Parameters
- llvm::StringRef PrefixDir
¶void setFallthrough(bool Fallthrough)
void setFallthrough(bool Fallthrough)
Description
Sets the redirection kind to \c Fallthrough if true or \c RedirectOnly otherwise. Will removed in the future, use \c setRedirection instead.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:993
Parameters
- bool Fallthrough
¶void setRedirection(
RedirectingFileSystem::RedirectKind Kind)
void setRedirection(
RedirectingFileSystem::RedirectKind Kind)
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:995
Parameters
- RedirectingFileSystem::RedirectKind Kind
¶ErrorOr<llvm::vfs::Status> status(
const llvm::Twine& Path)
ErrorOr<llvm::vfs::Status> status(
const llvm::Twine& Path)
Description
Get the status of the entry at \p Path, if one exists.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:971
Parameters
- const llvm::Twine& Path
¶ErrorOr<llvm::vfs::Status> status(
const llvm::Twine& CanonicalPath,
const llvm::Twine& OriginalPath,
const llvm::vfs::RedirectingFileSystem::
LookupResult& Result)
ErrorOr<llvm::vfs::Status> status(
const llvm::Twine& CanonicalPath,
const llvm::Twine& OriginalPath,
const llvm::vfs::RedirectingFileSystem::
LookupResult& Result)
Description
Get the status for a path with the provided \c LookupResult.
Declared at: llvm/include/llvm/Support/VirtualFileSystem.h:950
Parameters
- const llvm::Twine& CanonicalPath
- const llvm::Twine& OriginalPath
- const llvm::vfs::RedirectingFileSystem:: LookupResult& Result