//===- VirtualFileSystem.cpp - Virtual File System Layer --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// This file implements the VirtualFileSystem interface.
//===----------------------------------------------------------------------===//
#include "clang/Basic/VirtualFileSystem.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/YAMLParser.h"
#include <atomic>
#include <memory>
using namespace clang;
using namespace clang::vfs;
using namespace llvm;
using llvm::sys::fs::file_status;
using llvm::sys::fs::file_type;
using llvm::sys::fs::perms;
using llvm::sys::fs::UniqueID;
Status::Status(const file_status &Status)
: UID(Status.getUniqueID()), MTime(Status.getLastModificationTime()),
User(Status.getUser()), Group(Status.getGroup()), Size(Status.getSize()),
Type(Status.type()), Perms(Status.permissions()), IsVFSMapped(false) {}
Status::Status(StringRef Name, StringRef ExternalName, UniqueID UID,
sys::TimeValue MTime, uint32_t User, uint32_t Group,
uint64_t Size, file_type Type, perms Perms)
: Name(Name), UID(UID), MTime(MTime), User(User), Group(Group), Size(Size),
Type(Type), Perms(Perms), IsVFSMapped(false) {}
bool Status::equivalent(const Status &Other) const {
return getUniqueID() == Other.getUniqueID();
}
bool Status::isDirectory() const {
return Type == file_type::directory_file;
}
bool Status::isRegularFile() const {
return Type == file_type::regular_file;
}
bool Status::isOther() const {
return exists() && !isRegularFile() && !isDirectory() && !isSymlink();
}
bool Status::isSymlink() const {
return Type == file_type::symlink_file;
}
bool Status::isStatusKnown() const {
return Type != file_type::status_error;
}
bool Status::exists() const {
return isStatusKnown() && Type != file_type::file_not_found;
}
File::~File() {}
FileSystem::~FileSystem() {}
std::error_code FileSystem::getBufferForFile(
const llvm::Twine &Name, std::unique_ptr<MemoryBuffer> &Result,
int64_t FileSize, bool RequiresNullTerminator, bool IsVolatile) {
std::unique_ptr<File> F;
if (std::error_code EC = openFileForRead(Name, F))
return EC;
std::error_code EC =
F->getBuffer(Name, Result, FileSize, RequiresNullTerminator, IsVolatile);
return EC;
}
//===-----------------------------------------------------------------------===/
// RealFileSystem implementation
//===-----------------------------------------------------------------------===/
namespace {
/// \brief Wrapper around a raw file descriptor.
class RealFile : public File {
int FD;
Status S;
friend class RealFileSystem;
RealFile(int FD) : FD(FD) {
assert(FD >= 0 && "Invalid or inactive file descriptor");
}
public:
~RealFile();
ErrorOr<Status> status() override;
std::error_code getBuffer(const Twine &Name,
std::unique_ptr<MemoryBuffer> &Result,
int64_t FileSize = -1,
bool RequiresNullTerminator = true,
bool IsVolatile = false) override;
std::error_code close() override;
void setName(StringRef Name) override;
};
} // end anonymous namespace
RealFile::~RealFile() { close(); }
ErrorOr<Status> RealFile::status() {
assert(FD != -1 && "cannot stat closed file");
if (!S.isStatusKnown()) {
file_status RealStatus;
if (std::error_code EC = sys::fs::status(FD, RealStatus))
return EC;
Status NewS(RealStatus);
NewS.setName(S.getName());
S = std::move(NewS);
}
return S;
}
std::error_code RealFile::getBuffer(const Twine &Name,
std::unique_ptr<MemoryBuffer> &Result,
int64_t FileSize,
bool RequiresNullTerminator,
bool IsVolatile) {
assert(FD != -1 && "cannot get buffer for closed file");
ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
MemoryBuffer::getOpenFile(FD, Name.str().c_str(), FileSize,
RequiresNullTerminator, IsVolatile);
if (std::error_code EC = BufferOrErr.getError())
return EC;
Result = std::move(BufferOrErr.get());
return std::error_code();
}
// FIXME: This is terrible, we need this for ::close.
#if !defined(_MSC_VER) && !defined(__MINGW32__)
#include <unistd.h>
#include <sys/uio.h>
#else
#include <io.h>
#ifndef S_ISFIFO
#define S_ISFIFO(x) (0)
#endif
#endif
std::error_code RealFile::close() {
if (::close(FD))
return std::error_code(errno, std::generic_category());
FD = -1;
return std::error_code();
}
void RealFile::setName(StringRef Name) {
S.setName(Name);
}
namespace {
/// \brief The file system according to your operating system.
class RealFileSystem : public FileSystem {
public:
ErrorOr<Status> status(const Twine &Path) override;
std::error_code openFileForRead(const Twine &Path,
std::unique_ptr<File> &Result) override;
directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
};
} // end anonymous namespace
ErrorOr<Status> RealFileSystem::status(const Twine &Path) {
sys::fs::file_status RealStatus;
if (std::error_code EC = sys::fs::status(Path, RealStatus))
return EC;
Status Result(RealStatus);
Result.setName(Path.str());
return Result;
}
std::error_code RealFileSystem::openFileForRead(const Twine &Name,
std::unique_ptr<File> &Result) {
int FD;
if (std::error_code EC = sys::fs::openFileForRead(Name, FD))
return EC;
Result.reset(new RealFile(FD));
Result->setName(Name.str());
return std::error_code();
}
IntrusiveRefCntPtr<FileSystem> vfs::getRealFileSystem() {
static IntrusiveRefCntPtr<FileSystem> FS = new RealFileSystem();
return FS;
}
namespace {
class RealFSDirIter : public clang::vfs::detail::DirIterImpl {
std::string Path;
llvm::sys::fs::directory_iterator Iter;
public:
RealFSDirIter(const Twine &_Path, std::error_code &EC)
: Path(_Path.str()), Iter(Path, EC) {
if (!EC && Iter != llvm::sys::fs::directory_iterator()) {
llvm::sys::fs::file_status S;
EC = Iter->status(S);
if (!EC) {
CurrentEntry = Status(S);
CurrentEntry.setName(Iter->path());
}
}
}
std::error_code increment() override {
std::error_code EC;
Iter.increment(EC);
if (EC) {
return EC;
} else if (Iter == llvm::sys::fs::directory_iterator()) {
CurrentEntry = Status();
} else {
llvm::sys::fs::file_status S;
EC = Iter->status(S);
CurrentEntry = Status(S);
CurrentEntry.setName(Iter->path());
}
return EC;
}
};
}
directory_iterator RealFileSystem::dir_begin(const Twine &Dir,
std::error_code &EC) {
return directory_iterator(std::make_shared<RealFSDirIter>(Dir, EC));
}
//===-----------------------------------------------------------------------===/
// OverlayFileSystem implementation
//===-----------------------------------------------------------------------===/
OverlayFileSystem::OverlayFileSystem(IntrusiveRefCntPtr<FileSystem> BaseFS) {
pushOverlay(BaseFS);
}
void OverlayFileSystem::pushOverlay(IntrusiveRefCntPtr<FileSystem> FS) {
FSList.push_back(FS);
}
ErrorOr<Status> OverlayFileSystem::status(const Twine &Path) {
// FIXME: handle symlinks that cross file systems
for (iterator I = overlays_begin(), E = overlays_end(); I != E; ++I) {
ErrorOr<Status> Status = (*I)->status(Path);
if (Status || Status.getError() != llvm::errc::no_such_file_or_directory)
return Status;
}
return make_error_code(llvm::errc::no_such_file_or_directory);
}
std::error_code
OverlayFileSystem::openFileForRead(const llvm::Twine &Path,
std::unique_ptr<File> &Result) {
// FIXME: handle symlinks that cross file systems
for (iterator I = overlays_begin(), E = overlays_end(); I != E; ++I) {
std::error_code EC = (*I)->openFileForRead(Path, Result);
if (!EC || EC != llvm::errc::no_such_file_or_directory)
return EC;
}
return make_error_code(llvm::errc::no_such_file_or_directory);
}
clang::vfs::detail::DirIterImpl::~DirIterImpl() { }
namespace {
class OverlayFSDirIterImpl : public clang::vfs::detail::DirIterImpl {
OverlayFileSystem &Overlays;
std::string Path;
OverlayFileSystem::iterator CurrentFS;
directory_iterator CurrentDirIter;
llvm::StringSet<> SeenNames;
std::error_code incrementFS() {
assert(CurrentFS != Overlays.overlays_end() && "incrementing past end");
++CurrentFS;
for (auto E = Overlays.overlays_end(); CurrentFS != E; ++CurrentFS) {
std::error_code EC;
CurrentDirIter = (*CurrentFS)->dir_begin(Path, EC);
if (EC && EC != errc::no_such_file_or_directory)
return EC;
if (CurrentDirIter != directory_iterator())
break; // found
}
return std::error_code();
}
std::error_code incrementDirIter(bool IsFirstTime) {
assert((IsFirstTime || CurrentDirIter != directory_iterator()) &&
"incrementing past end");
std::error_code EC;
if (!IsFirstTime)
CurrentDirIter.increment(EC);
if (!EC && CurrentDirIter == directory_iterator())
EC = incrementFS();
return EC;
}
std::error_code incrementImpl(bool IsFirstTime) {
while (true) {
std::error_code EC = incrementDirIter(IsFirstTime);
if (EC || CurrentDirIter == directory_iterator()) {
CurrentEntry = Status();
return EC;
}
CurrentEntry = *CurrentDirIter;
StringRef Name = llvm::sys::path::filename(CurrentEntry.getName());
if (SeenNames.insert(Name))
return EC; // name not seen before
}
llvm_unreachable("returned above");
}
public:
OverlayFSDirIterImpl(const Twine &Path, OverlayFileSystem &FS,
std::error_code &EC)
: Overlays(FS), Path(Path.str()), CurrentFS(Overlays.overlays_begin()) {
CurrentDirIter = (*CurrentFS)->dir_begin(Path, EC);
EC = incrementImpl(true);
}
std::error_code increment() override { return incrementImpl(false); }
};
} // end anonymous namespace
directory_iterator OverlayFileSystem::dir_begin(const Twine &Dir,
std::error_code &EC) {
return directory_iterator(
std::make_shared<OverlayFSDirIterImpl>(Dir, *this, EC));
}
//===-----------------------------------------------------------------------===/
// VFSFromYAML implementation
//===-----------------------------------------------------------------------===/
// Allow DenseMap<StringRef, ...>. This is useful below because we know all the
// strings are literals and will outlive the map, and there is no reason to
// store them.
namespace llvm {
template<>
struct DenseMapInfo<StringRef> {
// This assumes that "" will never be a valid key.
static inline StringRef getEmptyKey() { return StringRef(""); }
static inline StringRef getTombstoneKey() { return StringRef(); }
static unsigned getHashValue(StringRef Val) { return HashString(Val); }
static bool isEqual(StringRef LHS, StringRef RHS) { return LHS == RHS; }
};
}
namespace {
enum EntryKind {
EK_Directory,
EK_File
};
/// \brief A single file or directory in the VFS.
class Entry {
EntryKind Kind;
std::string Name;
public:
virtual ~Entry();
Entry(EntryKind K, StringRef Name) : Kind(K), Name(Name) {}
StringRef getName() const { return Name; }
EntryKind getKind() const { return Kind; }
};
class DirectoryEntry : public Entry {
std::vector<Entry *> Contents;
Status S;
public:
virtual ~DirectoryEntry();
DirectoryEntry(StringRef Name, std::vector<Entry *> Contents, Status S)
: Entry(EK_Directory, Name), Contents(std::move(Contents)),
S(std::move(S)) {}
Status getStatus() { return S; }
typedef std::vector<Entry *>::iterator iterator;
iterator contents_begin() { return Contents.begin(); }
iterator contents_end() { return Contents.end(); }
static bool classof(const Entry *E) { return E->getKind() == EK_Directory; }
};
class FileEntry : public Entry {
public:
enum NameKind {
NK_NotSet,
NK_External,
NK_Virtual
};
private:
std::string ExternalContentsPath;
NameKind UseName;
public:
FileEntry(StringRef Name, StringRef ExternalContentsPath, NameKind UseName)
: Entry(EK_File, Name), ExternalContentsPath(ExternalContentsPath),
UseName(UseName) {}
StringRef getExternalContentsPath() const { return ExternalContentsPath; }
/// \brief whether to use the external path as the name for this file.
bool useExternalName(bool GlobalUseExternalName) const {
return UseName == NK_NotSet ? GlobalUseExternalName
: (UseName == NK_External);
}
static bool classof(const Entry *E) { return E->getKind() == EK_File; }
};
class VFSFromYAML;
class VFSFromYamlDirIterImpl : public clang::vfs::detail::DirIterImpl {
std::string Dir;
VFSFromYAML &FS;
DirectoryEntry::iterator Current, End;
public:
VFSFromYamlDirIterImpl(const Twine &Path, VFSFromYAML &FS,
DirectoryEntry::iterator Begin,
DirectoryEntry::iterator End, std::error_code &EC);
std::error_code increment() override;
};
/// \brief A virtual file system parsed from a YAML file.
///
/// Currently, this class allows creating virtual directories and mapping
/// virtual file paths to existing external files, available in \c ExternalFS.
///
/// The basic structure of the parsed file is:
/// \verbatim
/// {
/// 'version': <version number>,
/// <optional configuration>
/// 'roots': [
/// <directory entries>
/// ]
/// }
/// \endverbatim
///
/// All configuration options are optional.
/// 'case-sensitive': <boolean, default=true>
/// 'use-external-names': <boolean, default=true>
///
/// Virtual directories are represented as
/// \verbatim
/// {
/// 'type': 'directory',
/// 'name': <string>,
/// 'contents': [ <file or directory entries> ]
/// }
/// \endverbatim
///
/// The default attributes for virtual directories are:
/// \verbatim
/// MTime = now() when created
/// Perms = 0777
/// User = Group = 0
/// Size = 0
/// UniqueID = unspecified unique value
/// \endverbatim
///
/// Re-mapped files are represented as
/// \verbatim
/// {
/// 'type': 'file',
/// 'name': <string>,
/// 'use-external-name': <boolean> # Optional
/// 'external-contents': <path to external file>)
/// }
/// \endverbatim
///
/// and inherit their attributes from the external contents.
///
/// In both cases, the 'name' field may contain multiple path components (e.g.
/// /path/to/file). However, any directory that contains more than one child
/// must be uniquely represented by a directory entry.
class VFSFromYAML : public vfs::FileSystem {
std::vector<Entry *> Roots; ///< The root(s) of the virtual file system.
/// \brief The file system to use for external references.
IntrusiveRefCntPtr<FileSystem> ExternalFS;
/// @name Configuration
/// @{
/// \brief Whether to perform case-sensitive comparisons.
///
/// Currently, case-insensitive matching only works correctly with ASCII.
bool CaseSensitive;
/// \brief 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.
bool UseExternalNames;
/// @}
friend class VFSFromYAMLParser;
private:
VFSFromYAML(IntrusiveRefCntPtr<FileSystem> ExternalFS)
: ExternalFS(ExternalFS), CaseSensitive(true), UseExternalNames(true) {}
/// \brief Looks up \p Path in \c Roots.
ErrorOr<Entry *> lookupPath(const Twine &Path);
/// \brief Looks up the path <tt>[Start, End)</tt> in \p From, possibly
/// recursing into the contents of \p From if it is a directory.
ErrorOr<Entry *> lookupPath(sys::path::const_iterator Start,
sys::path::const_iterator End, Entry *From);
/// \brief Get the status of a given an \c Entry.
ErrorOr<Status> status(const Twine &Path, Entry *E);
public:
~VFSFromYAML();
/// \brief Parses \p Buffer, which is expected to be in YAML format and
/// returns a virtual file system representing its contents.
///
/// Takes ownership of \p Buffer.
static VFSFromYAML *create(MemoryBuffer *Buffer,
SourceMgr::DiagHandlerTy DiagHandler,
void *DiagContext,
IntrusiveRefCntPtr<FileSystem> ExternalFS);
ErrorOr<Status> status(const Twine &Path) override;
std::error_code openFileForRead(const Twine &Path,
std::unique_ptr<File> &Result) override;
directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override{
ErrorOr<Entry *> E = lookupPath(Dir);
if (!E) {
EC = E.getError();
return directory_iterator();
}
ErrorOr<Status> S = status(Dir, *E);
if (!S) {
EC = S.getError();
return directory_iterator();
}
if (!S->isDirectory()) {
EC = std::error_code(static_cast<int>(errc::not_a_directory),
std::system_category());
return directory_iterator();
}
DirectoryEntry *D = cast<DirectoryEntry>(*E);
return directory_iterator(std::make_shared<VFSFromYamlDirIterImpl>(Dir,
*this, D->contents_begin(), D->contents_end(), EC));
}
};
/// \brief A helper class to hold the common YAML parsing state.
class VFSFromYAMLParser {
yaml::Stream &Stream;
void error(yaml::Node *N, const Twine &Msg) {
Stream.printError(N, Msg);
}
// false on error
bool parseScalarString(yaml::Node *N, StringRef &Result,
SmallVectorImpl<char> &Storage) {
yaml::ScalarNode *S = dyn_cast<yaml::ScalarNode>(N);
if (!S) {
error(N, "expected string");
return false;
}
Result = S->getValue(Storage);
return true;
}
// false on error
bool parseScalarBool(yaml::Node *N, bool &Result) {
SmallString<5> Storage;
StringRef Value;
if (!parseScalarString(N, Value, Storage))
return false;
if (Value.equals_lower("true") || Value.equals_lower("on") ||
Value.equals_lower("yes") || Value == "1") {
Result = true;
return true;
} else if (Value.equals_lower("false") || Value.equals_lower("off") ||
Value.equals_lower("no") || Value == "0") {
Result = false;
return true;
}
error(N, "expected boolean value");
return false;
}
struct KeyStatus {
KeyStatus(bool Required=false) : Required(Required), Seen(false) {}
bool Required;
bool Seen;
};
typedef std::pair<StringRef, KeyStatus> KeyStatusPair;
// false on error
bool checkDuplicateOrUnknownKey(yaml::Node *KeyNode, StringRef Key,
DenseMap<StringRef, KeyStatus> &Keys) {
if (!Keys.count(Key)) {
error(KeyNode, "unknown key");
return false;
}
KeyStatus &S = Keys[Key];
if (S.Seen) {
error(KeyNode, Twine("duplicate key '") + Key + "'");
return false;
}
S.Seen = true;
return true;
}
// false on error
bool checkMissingKeys(yaml::Node *Obj, DenseMap<StringRef, KeyStatus> &Keys) {
for (DenseMap<StringRef, KeyStatus>::iterator I = Keys.begin(),
E = Keys.end();
I != E; ++I) {
if (I->second.Required && !I->second.Seen) {
error(Obj, Twine("missing key '") + I->first + "'");
return false;
}
}
return true;
}
Entry *parseEntry(yaml::Node *N) {
yaml::MappingNode *M = dyn_cast<yaml::MappingNode>(N);
if (!M) {
error(N, "expected mapping node for file or directory entry");
return nullptr;
}
KeyStatusPair Fields[] = {
KeyStatusPair("name", true),
KeyStatusPair("type", true),
KeyStatusPair("contents", false),
KeyStatusPair("external-contents", false),
KeyStatusPair("use-external-name", false),
};
DenseMap<StringRef, KeyStatus> Keys(
&Fields[0], Fields + sizeof(Fields)/sizeof(Fields[0]));
bool HasContents = false; // external or otherwise
std::vector<Entry *> EntryArrayContents;
std::string ExternalContentsPath;
std::string Name;
FileEntry::NameKind UseExternalName = FileEntry::NK_NotSet;
EntryKind Kind;
for (yaml::MappingNode::iterator I = M->begin(), E = M->end(); I != E;
++I) {
StringRef Key;
// Reuse the buffer for key and value, since we don't look at key after
// parsing value.
SmallString<256> Buffer;
if (!parseScalarString(I->getKey(), Key, Buffer))
return nullptr;
if (!checkDuplicateOrUnknownKey(I->getKey(), Key, Keys))
return nullptr;
StringRef Value;
if (Key == "name") {
if (!parseScalarString(I->getValue(), Value, Buffer))
return nullptr;
Name = Value;
} else if (Key == "type") {
if (!parseScalarString(I->getValue(), Value, Buffer))
return nullptr;
if (Value == "file")
Kind = EK_File;
else if (Value == "directory")
Kind = EK_Directory;
else {
error(I->getValue(), "unknown value for 'type'");
return nullptr;
}
} else if (Key == "contents") {
if (HasContents) {
error(I->getKey(),
"entry already has 'contents' or 'external-contents'");
return nullptr;
}
HasContents = true;
yaml::SequenceNode *Contents =
dyn_cast<yaml::SequenceNode>(I->getValue());
if (!Contents) {
// FIXME: this is only for directories, what about files?
error(I->getValue(), "expected array");
return nullptr;
}
for (yaml::SequenceNode::iterator I = Contents->begin(),
E = Contents->end();
I != E; ++I) {
if (Entry *E = parseEntry(&*I))
EntryArrayContents.push_back(E);
else
return nullptr;
}
} else if (Key == "external-contents") {
if (HasContents) {
error(I->getKey(),
"entry already has 'contents' or 'external-contents'");
return nullptr;
}
HasContents = true;
if (!parseScalarString(I->getValue(), Value, Buffer))
return nullptr;
ExternalContentsPath = Value;
} else if (Key == "use-external-name") {
bool Val;
if (!parseScalarBool(I->getValue(), Val))
return nullptr;
UseExternalName = Val ? FileEntry::NK_External : FileEntry::NK_Virtual;
} else {
llvm_unreachable("key missing from Keys");
}
}
if (Stream.failed())
return nullptr;
// check for missing keys
if (!HasContents) {
error(N, "missing key 'contents' or 'external-contents'");
return nullptr;
}
if (!checkMissingKeys(N, Keys))
return nullptr;
// check invalid configuration
if (Kind == EK_Directory && UseExternalName != FileEntry::NK_NotSet) {
error(N, "'use-external-name' is not supported for directories");
return nullptr;
}
// Remove trailing slash(es), being careful not to remove the root path
StringRef Trimmed(Name);
size_t RootPathLen = sys::path::root_path(Trimmed).size();
while (Trimmed.size() > RootPathLen &&
sys::path::is_separator(Trimmed.back()))
Trimmed = Trimmed.slice(0, Trimmed.size()-1);
// Get the last component
StringRef LastComponent = sys::path::filename(Trimmed);
Entry *Result = nullptr;
switch (Kind) {
case EK_File:
Result = new FileEntry(LastComponent, std::move(ExternalContentsPath),
UseExternalName);
break;
case EK_Directory:
Result = new DirectoryEntry(LastComponent, std::move(EntryArrayContents),
Status("", "", getNextVirtualUniqueID(), sys::TimeValue::now(), 0, 0,
0, file_type::directory_file, sys::fs::all_all));
break;
}
StringRef Parent = sys::path::parent_path(Trimmed);
if (Parent.empty())
return Result;
// if 'name' contains multiple components, create implicit directory entries
for (sys::path::reverse_iterator I = sys::path::rbegin(Parent),
E = sys::path::rend(Parent);
I != E; ++I) {
Result = new DirectoryEntry(*I, llvm::makeArrayRef(Result),
Status("", "", getNextVirtualUniqueID(), sys::TimeValue::now(), 0, 0,
0, file_type::directory_file, sys::fs::all_all));
}
return Result;
}
public:
VFSFromYAMLParser(yaml::Stream &S) : Stream(S) {}
// false on error
bool parse(yaml::Node *Root, VFSFromYAML *FS) {
yaml::MappingNode *Top = dyn_cast<yaml::MappingNode>(Root);
if (!Top) {
error(Root, "expected mapping node");
return false;
}
KeyStatusPair Fields[] = {
KeyStatusPair("version", true),
KeyStatusPair("case-sensitive", false),
KeyStatusPair("use-external-names", false),
KeyStatusPair("roots", true),
};
DenseMap<StringRef, KeyStatus> Keys(
&Fields[0], Fields + sizeof(Fields)/sizeof(Fields[0]));
// Parse configuration and 'roots'
for (yaml::MappingNode::iterator I = Top->begin(), E = Top->end(); I != E;
++I) {
SmallString<10> KeyBuffer;
StringRef Key;
if (!parseScalarString(I->getKey(), Key, KeyBuffer))
return false;
if (!checkDuplicateOrUnknownKey(I->getKey(), Key, Keys))
return false;
if (Key == "roots") {
yaml::SequenceNode *Roots = dyn_cast<yaml::SequenceNode>(I->getValue());
if (!Roots) {
error(I->getValue(), "expected array");
return false;
}
for (yaml::SequenceNode::iterator I = Roots->begin(), E = Roots->end();
I != E; ++I) {
if (Entry *E = parseEntry(&*I))
FS->Roots.push_back(E);
else
return false;
}
} else if (Key == "version") {
StringRef VersionString;
SmallString<4> Storage;
if (!parseScalarString(I->getValue(), VersionString, Storage))
return false;
int Version;
if (VersionString.getAsInteger<int>(10, Version)) {
error(I->getValue(), "expected integer");
return false;
}
if (Version < 0) {
error(I->getValue(), "invalid version number");
return false;
}
if (Version != 0) {
error(I->getValue(), "version mismatch, expected 0");
return false;
}
} else if (Key == "case-sensitive") {
if (!parseScalarBool(I->getValue(), FS->CaseSensitive))
return false;
} else if (Key == "use-external-names") {
if (!parseScalarBool(I->getValue(), FS->UseExternalNames))
return false;
} else {
llvm_unreachable("key missing from Keys");
}
}
if (Stream.failed())
return false;
if (!checkMissingKeys(Top, Keys))
return false;
return true;
}
};
} // end of anonymous namespace
Entry::~Entry() {}
DirectoryEntry::~DirectoryEntry() { llvm::DeleteContainerPointers(Contents); }
VFSFromYAML::~VFSFromYAML() { llvm::DeleteContainerPointers(Roots); }
VFSFromYAML *VFSFromYAML::create(MemoryBuffer *Buffer,
SourceMgr::DiagHandlerTy DiagHandler,
void *DiagContext,
IntrusiveRefCntPtr<FileSystem> ExternalFS) {
SourceMgr SM;
yaml::Stream Stream(Buffer, SM);
SM.setDiagHandler(DiagHandler, DiagContext);
yaml::document_iterator DI = Stream.begin();
yaml::Node *Root = DI->getRoot();
if (DI == Stream.end() || !Root) {
SM.PrintMessage(SMLoc(), SourceMgr::DK_Error, "expected root node");
return nullptr;
}
VFSFromYAMLParser P(Stream);
std::unique_ptr<VFSFromYAML> FS(new VFSFromYAML(ExternalFS));
if (!P.parse(Root, FS.get()))
return nullptr;
return FS.release();
}
ErrorOr<Entry *> VFSFromYAML::lookupPath(const Twine &Path_) {
SmallString<256> Path;
Path_.toVector(Path);
// Handle relative paths
if (std::error_code EC = sys::fs::make_absolute(Path))
return EC;
if (Path.empty())
return make_error_code(llvm::errc::invalid_argument);
sys::path::const_iterator Start = sys::path::begin(Path);
sys::path::const_iterator End = sys::path::end(Path);
for (std::vector<Entry *>::iterator I = Roots.begin(), E = Roots.end();
I != E; ++I) {
ErrorOr<Entry *> Result = lookupPath(Start, End, *I);
if (Result || Result.getError() != llvm::errc::no_such_file_or_directory)
return Result;
}
return make_error_code(llvm::errc::no_such_file_or_directory);
}
ErrorOr<Entry *> VFSFromYAML::lookupPath(sys::path::const_iterator Start,
sys::path::const_iterator End,
Entry *From) {
if (Start->equals("."))
++Start;
// FIXME: handle ..
if (CaseSensitive ? !Start->equals(From->getName())
: !Start->equals_lower(From->getName()))
// failure to match
return make_error_code(llvm::errc::no_such_file_or_directory);
++Start;
if (Start == End) {
// Match!
return From;
}
DirectoryEntry *DE = dyn_cast<DirectoryEntry>(From);
if (!DE)
return make_error_code(llvm::errc::not_a_directory);
for (DirectoryEntry::iterator I = DE->contents_begin(),
E = DE->contents_end();
I != E; ++I) {
ErrorOr<Entry *> Result = lookupPath(Start, End, *I);
if (Result || Result.getError() != llvm::errc::no_such_file_or_directory)
return Result;
}
return make_error_code(llvm::errc::no_such_file_or_directory);
}
ErrorOr<Status> VFSFromYAML::status(const Twine &Path, Entry *E) {
assert(E != nullptr);
std::string PathStr(Path.str());
if (FileEntry *F = dyn_cast<FileEntry>(E)) {
ErrorOr<Status> S = ExternalFS->status(F->getExternalContentsPath());
assert(!S || S->getName() == F->getExternalContentsPath());
if (S && !F->useExternalName(UseExternalNames))
S->setName(PathStr);
if (S)
S->IsVFSMapped = true;
return S;
} else { // directory
DirectoryEntry *DE = cast<DirectoryEntry>(E);
Status S = DE->getStatus();
S.setName(PathStr);
return S;
}
}
ErrorOr<Status> VFSFromYAML::status(const Twine &Path) {
ErrorOr<Entry *> Result = lookupPath(Path);
if (!Result)
return Result.getError();
return status(Path, *Result);
}
std::error_code
VFSFromYAML::openFileForRead(const Twine &Path,
std::unique_ptr<vfs::File> &Result) {
ErrorOr<Entry *> E = lookupPath(Path);
if (!E)
return E.getError();
FileEntry *F = dyn_cast<FileEntry>(*E);
if (!F) // FIXME: errc::not_a_file?
return make_error_code(llvm::errc::invalid_argument);
if (std::error_code EC =
ExternalFS->openFileForRead(F->getExternalContentsPath(), Result))
return EC;
if (!F->useExternalName(UseExternalNames))
Result->setName(Path.str());
return std::error_code();
}
IntrusiveRefCntPtr<FileSystem>
vfs::getVFSFromYAML(MemoryBuffer *Buffer, SourceMgr::DiagHandlerTy DiagHandler,
void *DiagContext,
IntrusiveRefCntPtr<FileSystem> ExternalFS) {
return VFSFromYAML::create(Buffer, DiagHandler, DiagContext, ExternalFS);
}
UniqueID vfs::getNextVirtualUniqueID() {
static std::atomic<unsigned> UID;
unsigned ID = ++UID;
// The following assumes that uint64_t max will never collide with a real
// dev_t value from the OS.
return UniqueID(std::numeric_limits<uint64_t>::max(), ID);
}
#ifndef NDEBUG
static bool pathHasTraversal(StringRef Path) {
using namespace llvm::sys;
for (StringRef Comp : llvm::make_range(path::begin(Path), path::end(Path)))
if (Comp == "." || Comp == "..")
return true;
return false;
}
#endif
void YAMLVFSWriter::addFileMapping(StringRef VirtualPath, StringRef RealPath) {
assert(sys::path::is_absolute(VirtualPath) && "virtual path not absolute");
assert(sys::path::is_absolute(RealPath) && "real path not absolute");
assert(!pathHasTraversal(VirtualPath) && "path traversal is not supported");
Mappings.emplace_back(VirtualPath, RealPath);
}
namespace {
class JSONWriter {
llvm::raw_ostream &OS;
SmallVector<StringRef, 16> DirStack;
inline unsigned getDirIndent() { return 4 * DirStack.size(); }
inline unsigned getFileIndent() { return 4 * (DirStack.size() + 1); }
bool containedIn(StringRef Parent, StringRef Path);
StringRef containedPart(StringRef Parent, StringRef Path);
void startDirectory(StringRef Path);
void endDirectory();
void writeEntry(StringRef VPath, StringRef RPath);
public:
JSONWriter(llvm::raw_ostream &OS) : OS(OS) {}
void write(ArrayRef<YAMLVFSEntry> Entries, Optional<bool> IsCaseSensitive);
};
}
bool JSONWriter::containedIn(StringRef Parent, StringRef Path) {
using namespace llvm::sys;
// Compare each path component.
auto IParent = path::begin(Parent), EParent = path::end(Parent);
for (auto IChild = path::begin(Path), EChild = path::end(Path);
IParent != EParent && IChild != EChild; ++IParent, ++IChild) {
if (*IParent != *IChild)
return false;
}
// Have we exhausted the parent path?
return IParent == EParent;
}
StringRef JSONWriter::containedPart(StringRef Parent, StringRef Path) {
assert(!Parent.empty());
assert(containedIn(Parent, Path));
return Path.slice(Parent.size() + 1, StringRef::npos);
}
void JSONWriter::startDirectory(StringRef Path) {
StringRef Name =
DirStack.empty() ? Path : containedPart(DirStack.back(), Path);
DirStack.push_back(Path);
unsigned Indent = getDirIndent();
OS.indent(Indent) << "{\n";
OS.indent(Indent + 2) << "'type': 'directory',\n";
OS.indent(Indent + 2) << "'name': \"" << llvm::yaml::escape(Name) << "\",\n";
OS.indent(Indent + 2) << "'contents': [\n";
}
void JSONWriter::endDirectory() {
unsigned Indent = getDirIndent();
OS.indent(Indent + 2) << "]\n";
OS.indent(Indent) << "}";
DirStack.pop_back();
}
void JSONWriter::writeEntry(StringRef VPath, StringRef RPath) {
unsigned Indent = getFileIndent();
OS.indent(Indent) << "{\n";
OS.indent(Indent + 2) << "'type': 'file',\n";
OS.indent(Indent + 2) << "'name': \"" << llvm::yaml::escape(VPath) << "\",\n";
OS.indent(Indent + 2) << "'external-contents': \""
<< llvm::yaml::escape(RPath) << "\"\n";
OS.indent(Indent) << "}";
}
void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
Optional<bool> IsCaseSensitive) {
using namespace llvm::sys;
OS << "{\n"
" 'version': 0,\n";
if (IsCaseSensitive.hasValue())
OS << " 'case-sensitive': '"
<< (IsCaseSensitive.getValue() ? "true" : "false") << "',\n";
OS << " 'roots': [\n";
if (Entries.empty())
return;
const YAMLVFSEntry &Entry = Entries.front();
startDirectory(path::parent_path(Entry.VPath));
writeEntry(path::filename(Entry.VPath), Entry.RPath);
for (const auto &Entry : Entries.slice(1)) {
StringRef Dir = path::parent_path(Entry.VPath);
if (Dir == DirStack.back())
OS << ",\n";
else {
while (!DirStack.empty() && !containedIn(DirStack.back(), Dir)) {
OS << "\n";
endDirectory();
}
OS << ",\n";
startDirectory(Dir);
}
writeEntry(path::filename(Entry.VPath), Entry.RPath);
}
while (!DirStack.empty()) {
OS << "\n";
endDirectory();
}
OS << "\n"
<< " ]\n"
<< "}\n";
}
void YAMLVFSWriter::write(llvm::raw_ostream &OS) {
std::sort(Mappings.begin(), Mappings.end(),
[](const YAMLVFSEntry &LHS, const YAMLVFSEntry &RHS) {
return LHS.VPath < RHS.VPath;
});
JSONWriter(OS).write(Mappings, IsCaseSensitive);
}
VFSFromYamlDirIterImpl::VFSFromYamlDirIterImpl(const Twine &_Path,
VFSFromYAML &FS,
DirectoryEntry::iterator Begin,
DirectoryEntry::iterator End,
std::error_code &EC)
: Dir(_Path.str()), FS(FS), Current(Begin), End(End) {
if (Current != End) {
SmallString<128> PathStr(Dir);
llvm::sys::path::append(PathStr, (*Current)->getName());
llvm::ErrorOr<vfs::Status> S = FS.status(PathStr.str());
if (S)
CurrentEntry = *S;
else
EC = S.getError();
}
}
std::error_code VFSFromYamlDirIterImpl::increment() {
assert(Current != End && "cannot iterate past end");
if (++Current != End) {
SmallString<128> PathStr(Dir);
llvm::sys::path::append(PathStr, (*Current)->getName());
llvm::ErrorOr<vfs::Status> S = FS.status(PathStr.str());
if (!S)
return S.getError();
CurrentEntry = *S;
} else {
CurrentEntry = Status();
}
return std::error_code();
}
vfs::recursive_directory_iterator::recursive_directory_iterator(FileSystem &FS_,
const Twine &Path,
std::error_code &EC)
: FS(&FS_) {
directory_iterator I = FS->dir_begin(Path, EC);
if (!EC && I != directory_iterator()) {
State = std::make_shared<IterState>();
State->push(I);
}
}
vfs::recursive_directory_iterator &
recursive_directory_iterator::increment(std::error_code &EC) {
assert(FS && State && !State->empty() && "incrementing past end");
assert(State->top()->isStatusKnown() && "non-canonical end iterator");
vfs::directory_iterator End;
if (State->top()->isDirectory()) {
vfs::directory_iterator I = FS->dir_begin(State->top()->getName(), EC);
if (EC)
return *this;
if (I != End) {
State->push(I);
return *this;
}
}
while (!State->empty() && State->top().increment(EC) == End)
State->pop();
if (State->empty())
State.reset(); // end iterator
return *this;
}