Coverage Report

Created: 2019-07-24 05:18

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/include/llvm/Support/VirtualFileSystem.h
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//===- VirtualFileSystem.h - Virtual File System Layer ----------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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/// \file
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/// Defines the virtual file system interface vfs::FileSystem.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_SUPPORT_VIRTUALFILESYSTEM_H
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#define LLVM_SUPPORT_VIRTUALFILESYSTEM_H
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#include "llvm/ADT/IntrusiveRefCntPtr.h"
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#include "llvm/ADT/None.h"
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#include "llvm/ADT/Optional.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/ADT/Twine.h"
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#include "llvm/Support/Chrono.h"
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#include "llvm/Support/ErrorOr.h"
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#include "llvm/Support/FileSystem.h"
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#include "llvm/Support/Path.h"
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#include "llvm/Support/SourceMgr.h"
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#include <cassert>
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#include <cstdint>
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#include <ctime>
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#include <memory>
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#include <stack>
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#include <string>
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#include <system_error>
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#include <utility>
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#include <vector>
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namespace llvm {
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class MemoryBuffer;
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namespace vfs {
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/// The result of a \p status operation.
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class Status {
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  std::string Name;
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  llvm::sys::fs::UniqueID UID;
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  llvm::sys::TimePoint<> MTime;
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  uint32_t User;
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  uint32_t Group;
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  uint64_t Size;
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  llvm::sys::fs::file_type Type = llvm::sys::fs::file_type::status_error;
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  llvm::sys::fs::perms Perms;
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public:
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  // FIXME: remove when files support multiple names
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  bool IsVFSMapped = false;
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1.18M
  Status() = default;
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  Status(const llvm::sys::fs::file_status &Status);
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  Status(const Twine &Name, llvm::sys::fs::UniqueID UID,
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         llvm::sys::TimePoint<> MTime, uint32_t User, uint32_t Group,
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         uint64_t Size, llvm::sys::fs::file_type Type,
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         llvm::sys::fs::perms Perms);
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  /// Get a copy of a Status with a different name.
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  static Status copyWithNewName(const Status &In, const Twine &NewName);
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  static Status copyWithNewName(const llvm::sys::fs::file_status &In,
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                                const Twine &NewName);
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  /// Returns the name that should be used for this file or directory.
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1.31M
  StringRef getName() const { return Name; }
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  /// @name Status interface from llvm::sys::fs
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  /// @{
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731k
  llvm::sys::fs::file_type getType() const { return Type; }
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118k
  llvm::sys::fs::perms getPermissions() const { return Perms; }
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731k
  llvm::sys::TimePoint<> getLastModificationTime() const { return MTime; }
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1.57M
  llvm::sys::fs::UniqueID getUniqueID() const { return UID; }
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118k
  uint32_t getUser() const { return User; }
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118k
  uint32_t getGroup() const { return Group; }
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731k
  uint64_t getSize() const { return Size; }
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  /// @}
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  /// @name Status queries
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  /// These are static queries in llvm::sys::fs.
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  /// @{
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  bool equivalent(const Status &Other) const;
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  bool isDirectory() const;
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  bool isRegularFile() const;
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  bool isOther() const;
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  bool isSymlink() const;
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  bool isStatusKnown() const;
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  bool exists() const;
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  /// @}
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};
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/// Represents an open file.
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class File {
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public:
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  /// Destroy the file after closing it (if open).
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  /// Sub-classes should generally call close() inside their destructors.  We
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  /// cannot do that from the base class, since close is virtual.
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  virtual ~File();
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  /// Get the status of the file.
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  virtual llvm::ErrorOr<Status> status() = 0;
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  /// Get the name of the file
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7.39k
  virtual llvm::ErrorOr<std::string> getName() {
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7.39k
    if (auto Status = status())
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7.39k
      return Status->getName().str();
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0
    else
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0
      return Status.getError();
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7.39k
  }
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  /// Get the contents of the file as a \p MemoryBuffer.
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  virtual llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
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  getBuffer(const Twine &Name, int64_t FileSize = -1,
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            bool RequiresNullTerminator = true, bool IsVolatile = false) = 0;
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  /// Closes the file.
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  virtual std::error_code close() = 0;
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};
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/// A member of a directory, yielded by a directory_iterator.
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/// Only information available on most platforms is included.
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class directory_entry {
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  std::string Path;
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  llvm::sys::fs::file_type Type;
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public:
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417k
  directory_entry() = default;
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  directory_entry(std::string Path, llvm::sys::fs::file_type Type)
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9.46k
      : Path(std::move(Path)), Type(Type) {}
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  llvm::StringRef path() const { return Path; }
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3.83k
  llvm::sys::fs::file_type type() const { return Type; }
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};
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namespace detail {
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/// An interface for virtual file systems to provide an iterator over the
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/// (non-recursive) contents of a directory.
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struct DirIterImpl {
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  virtual ~DirIterImpl();
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  /// Sets \c CurrentEntry to the next entry in the directory on success,
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  /// to directory_entry() at end,  or returns a system-defined \c error_code.
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  virtual std::error_code increment() = 0;
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  directory_entry CurrentEntry;
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};
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} // namespace detail
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/// An input iterator over the entries in a virtual path, similar to
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/// llvm::sys::fs::directory_iterator.
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class directory_iterator {
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  std::shared_ptr<detail::DirIterImpl> Impl; // Input iterator semantics on copy
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public:
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  directory_iterator(std::shared_ptr<detail::DirIterImpl> I)
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415k
      : Impl(std::move(I)) {
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415k
    assert(Impl.get() != nullptr && "requires non-null implementation");
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415k
    if (Impl->CurrentEntry.path().empty())
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      Impl.reset(); // Normalize the end iterator to Impl == nullptr.
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415k
  }
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  /// Construct an 'end' iterator.
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419k
  directory_iterator() = default;
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  /// Equivalent to operator++, with an error code.
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9.51k
  directory_iterator &increment(std::error_code &EC) {
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9.51k
    assert(Impl && "attempting to increment past end");
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9.51k
    EC = Impl->increment();
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9.51k
    if (Impl->CurrentEntry.path().empty())
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1.82k
      Impl.reset(); // Normalize the end iterator to Impl == nullptr.
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    return *this;
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  }
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  const directory_entry &operator*() const { return Impl->CurrentEntry; }
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  const directory_entry *operator->() const { return &Impl->CurrentEntry; }
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  bool operator==(const directory_iterator &RHS) const {
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11.6k
    if (Impl && 
RHS.Impl9.57k
)
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0
      return Impl->CurrentEntry.path() == RHS.Impl->CurrentEntry.path();
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11.6k
    return !Impl && 
!RHS.Impl2.11k
;
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11.6k
  }
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10.3k
  bool operator!=(const directory_iterator &RHS) const {
190
10.3k
    return !(*this == RHS);
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10.3k
  }
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};
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class FileSystem;
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namespace detail {
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/// Keeps state for the recursive_directory_iterator.
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struct RecDirIterState {
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  std::stack<directory_iterator, std::vector<directory_iterator>> Stack;
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  bool HasNoPushRequest = false;
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};
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} // end namespace detail
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/// An input iterator over the recursive contents of a virtual path,
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/// similar to llvm::sys::fs::recursive_directory_iterator.
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class recursive_directory_iterator {
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  FileSystem *FS;
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  std::shared_ptr<detail::RecDirIterState>
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      State; // Input iterator semantics on copy.
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public:
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  recursive_directory_iterator(FileSystem &FS, const Twine &Path,
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                               std::error_code &EC);
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  /// Construct an 'end' iterator.
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  recursive_directory_iterator() = default;
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  /// Equivalent to operator++, with an error code.
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  recursive_directory_iterator &increment(std::error_code &EC);
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0
  const directory_entry &operator*() const { return *State->Stack.top(); }
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2.22k
  const directory_entry *operator->() const { return &*State->Stack.top(); }
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1.44k
  bool operator==(const recursive_directory_iterator &Other) const {
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1.44k
    return State == Other.State; // identity
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1.44k
  }
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1.44k
  bool operator!=(const recursive_directory_iterator &RHS) const {
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1.44k
    return !(*this == RHS);
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1.44k
  }
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  /// Gets the current level. Starting path is at level 0.
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  int level() const {
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    assert(!State->Stack.empty() &&
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           "Cannot get level without any iteration state");
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    return State->Stack.size() - 1;
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  }
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  void no_push() { State->HasNoPushRequest = true; }
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};
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/// The virtual file system interface.
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class FileSystem : public llvm::ThreadSafeRefCountedBase<FileSystem> {
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public:
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  virtual ~FileSystem();
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  /// Get the status of the entry at \p Path, if one exists.
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  virtual llvm::ErrorOr<Status> status(const Twine &Path) = 0;
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  /// Get a \p File object for the file at \p Path, if one exists.
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  virtual llvm::ErrorOr<std::unique_ptr<File>>
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  openFileForRead(const Twine &Path) = 0;
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  /// This is a convenience method that opens a file, gets its content and then
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  /// closes the file.
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  llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
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  getBufferForFile(const Twine &Name, int64_t FileSize = -1,
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                   bool RequiresNullTerminator = true, bool IsVolatile = false);
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  /// Get a directory_iterator for \p Dir.
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  /// \note The 'end' iterator is directory_iterator().
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  virtual directory_iterator dir_begin(const Twine &Dir,
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                                       std::error_code &EC) = 0;
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  /// Set the working directory. This will affect all following operations on
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  /// this file system and may propagate down for nested file systems.
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  virtual std::error_code setCurrentWorkingDirectory(const Twine &Path) = 0;
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  /// Get the working directory of this file system.
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  virtual llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const = 0;
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  /// Gets real path of \p Path e.g. collapse all . and .. patterns, resolve
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  /// symlinks. For real file system, this uses `llvm::sys::fs::real_path`.
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  /// This returns errc::operation_not_permitted if not implemented by subclass.
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  virtual std::error_code getRealPath(const Twine &Path,
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                                      SmallVectorImpl<char> &Output) const;
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  /// Check whether a file exists. Provided for convenience.
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  bool exists(const Twine &Path);
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  /// Is the file mounted on a local filesystem?
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  virtual std::error_code isLocal(const Twine &Path, bool &Result);
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  /// Make \a Path an absolute path.
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  ///
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  /// Makes \a Path absolute using the current directory if it is not already.
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  /// An empty \a Path will result in the current directory.
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  ///
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  /// /absolute/path   => /absolute/path
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  /// relative/../path => <current-directory>/relative/../path
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  ///
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  /// \param Path A path that is modified to be an absolute path.
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  /// \returns success if \a path has been made absolute, otherwise a
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  ///          platform-specific error_code.
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  std::error_code makeAbsolute(SmallVectorImpl<char> &Path) const;
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};
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/// Gets an \p vfs::FileSystem for the 'real' file system, as seen by
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/// the operating system.
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/// The working directory is linked to the process's working directory.
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/// (This is usually thread-hostile).
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IntrusiveRefCntPtr<FileSystem> getRealFileSystem();
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/// Create an \p vfs::FileSystem for the 'real' file system, as seen by
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/// the operating system.
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/// It has its own working directory, independent of (but initially equal to)
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/// that of the process.
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std::unique_ptr<FileSystem> createPhysicalFileSystem();
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/// A file system that allows overlaying one \p AbstractFileSystem on top
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/// of another.
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///
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/// Consists of a stack of >=1 \p FileSystem objects, which are treated as being
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/// one merged file system. When there is a directory that exists in more than
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/// one file system, the \p OverlayFileSystem contains a directory containing
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/// the union of their contents.  The attributes (permissions, etc.) of the
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/// top-most (most recently added) directory are used.  When there is a file
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/// that exists in more than one file system, the file in the top-most file
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/// system overrides the other(s).
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class OverlayFileSystem : public FileSystem {
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  using FileSystemList = SmallVector<IntrusiveRefCntPtr<FileSystem>, 1>;
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  /// The stack of file systems, implemented as a list in order of
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  /// their addition.
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  FileSystemList FSList;
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public:
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  OverlayFileSystem(IntrusiveRefCntPtr<FileSystem> Base);
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  /// Pushes a file system on top of the stack.
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  void pushOverlay(IntrusiveRefCntPtr<FileSystem> FS);
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  llvm::ErrorOr<Status> status(const Twine &Path) override;
335
  llvm::ErrorOr<std::unique_ptr<File>>
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  openFileForRead(const Twine &Path) override;
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  directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
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  llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override;
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  std::error_code setCurrentWorkingDirectory(const Twine &Path) override;
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  std::error_code isLocal(const Twine &Path, bool &Result) override;
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  std::error_code getRealPath(const Twine &Path,
342
                              SmallVectorImpl<char> &Output) const override;
343
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  using iterator = FileSystemList::reverse_iterator;
345
  using const_iterator = FileSystemList::const_reverse_iterator;
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  using reverse_iterator = FileSystemList::iterator;
347
  using const_reverse_iterator = FileSystemList::const_iterator;
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  /// Get an iterator pointing to the most recently added file system.
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273k
  iterator overlays_begin() { return FSList.rbegin(); }
351
0
  const_iterator overlays_begin() const { return FSList.rbegin(); }
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  /// Get an iterator pointing one-past the least recently added file system.
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271k
  iterator overlays_end() { return FSList.rend(); }
355
0
  const_iterator overlays_end() const { return FSList.rend(); }
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  /// Get an iterator pointing to the least recently added file system.
358
  reverse_iterator overlays_rbegin() { return FSList.begin(); }
359
0
  const_reverse_iterator overlays_rbegin() const { return FSList.begin(); }
360
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  /// Get an iterator pointing one-past the most recently added file system.
362
  reverse_iterator overlays_rend() { return FSList.end(); }
363
0
  const_reverse_iterator overlays_rend() const { return FSList.end(); }
364
};
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/// By default, this delegates all calls to the underlying file system. This
367
/// is useful when derived file systems want to override some calls and still
368
/// proxy other calls.
369
class ProxyFileSystem : public FileSystem {
370
public:
371
  explicit ProxyFileSystem(IntrusiveRefCntPtr<FileSystem> FS)
372
      : FS(std::move(FS)) {}
373
374
251
  llvm::ErrorOr<Status> status(const Twine &Path) override {
375
251
    return FS->status(Path);
376
251
  }
377
  llvm::ErrorOr<std::unique_ptr<File>>
378
108
  openFileForRead(const Twine &Path) override {
379
108
    return FS->openFileForRead(Path);
380
108
  }
381
1
  directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override {
382
1
    return FS->dir_begin(Dir, EC);
383
1
  }
384
1
  llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override {
385
1
    return FS->getCurrentWorkingDirectory();
386
1
  }
387
1
  std::error_code setCurrentWorkingDirectory(const Twine &Path) override {
388
1
    return FS->setCurrentWorkingDirectory(Path);
389
1
  }
390
  std::error_code getRealPath(const Twine &Path,
391
1
                              SmallVectorImpl<char> &Output) const override {
392
1
    return FS->getRealPath(Path, Output);
393
1
  }
394
1
  std::error_code isLocal(const Twine &Path, bool &Result) override {
395
1
    return FS->isLocal(Path, Result);
396
1
  }
397
398
protected:
399
0
  FileSystem &getUnderlyingFS() { return *FS; }
400
401
private:
402
  IntrusiveRefCntPtr<FileSystem> FS;
403
404
  virtual void anchor();
405
};
406
407
namespace detail {
408
409
class InMemoryDirectory;
410
class InMemoryFile;
411
412
} // namespace detail
413
414
/// An in-memory file system.
415
class InMemoryFileSystem : public FileSystem {
416
  std::unique_ptr<detail::InMemoryDirectory> Root;
417
  std::string WorkingDirectory;
418
  bool UseNormalizedPaths = true;
419
420
  /// If HardLinkTarget is non-null, a hardlink is created to the To path which
421
  /// must be a file. If it is null then it adds the file as the public addFile.
422
  bool addFile(const Twine &Path, time_t ModificationTime,
423
               std::unique_ptr<llvm::MemoryBuffer> Buffer,
424
               Optional<uint32_t> User, Optional<uint32_t> Group,
425
               Optional<llvm::sys::fs::file_type> Type,
426
               Optional<llvm::sys::fs::perms> Perms,
427
               const detail::InMemoryFile *HardLinkTarget);
428
429
public:
430
  explicit InMemoryFileSystem(bool UseNormalizedPaths = true);
431
  ~InMemoryFileSystem() override;
432
433
  /// Add a file containing a buffer or a directory to the VFS with a
434
  /// path. The VFS owns the buffer.  If present, User, Group, Type
435
  /// and Perms apply to the newly-created file or directory.
436
  /// \return true if the file or directory was successfully added,
437
  /// false if the file or directory already exists in the file system with
438
  /// different contents.
439
  bool addFile(const Twine &Path, time_t ModificationTime,
440
               std::unique_ptr<llvm::MemoryBuffer> Buffer,
441
               Optional<uint32_t> User = None, Optional<uint32_t> Group = None,
442
               Optional<llvm::sys::fs::file_type> Type = None,
443
               Optional<llvm::sys::fs::perms> Perms = None);
444
445
  /// Add a hard link to a file.
446
  /// Here hard links are not intended to be fully equivalent to the classical
447
  /// filesystem. Both the hard link and the file share the same buffer and
448
  /// status (and thus have the same UniqueID). Because of this there is no way
449
  /// to distinguish between the link and the file after the link has been
450
  /// added.
451
  ///
452
  /// The To path must be an existing file or a hardlink. The From file must not
453
  /// have been added before. The To Path must not be a directory. The From Node
454
  /// is added as a hard link which points to the resolved file of To Node.
455
  /// \return true if the above condition is satisfied and hardlink was
456
  /// successfully created, false otherwise.
457
  bool addHardLink(const Twine &From, const Twine &To);
458
459
  /// Add a buffer to the VFS with a path. The VFS does not own the buffer.
460
  /// If present, User, Group, Type and Perms apply to the newly-created file
461
  /// or directory.
462
  /// \return true if the file or directory was successfully added,
463
  /// false if the file or directory already exists in the file system with
464
  /// different contents.
465
  bool addFileNoOwn(const Twine &Path, time_t ModificationTime,
466
                    llvm::MemoryBuffer *Buffer, Optional<uint32_t> User = None,
467
                    Optional<uint32_t> Group = None,
468
                    Optional<llvm::sys::fs::file_type> Type = None,
469
                    Optional<llvm::sys::fs::perms> Perms = None);
470
471
  std::string toString() const;
472
473
  /// Return true if this file system normalizes . and .. in paths.
474
474k
  bool useNormalizedPaths() const { return UseNormalizedPaths; }
475
476
  llvm::ErrorOr<Status> status(const Twine &Path) override;
477
  llvm::ErrorOr<std::unique_ptr<File>>
478
  openFileForRead(const Twine &Path) override;
479
  directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
480
481
301k
  llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override {
482
301k
    return WorkingDirectory;
483
301k
  }
484
  /// Canonicalizes \p Path by combining with the current working
485
  /// directory and normalizing the path (e.g. remove dots). If the current
486
  /// working directory is not set, this returns errc::operation_not_permitted.
487
  ///
488
  /// This doesn't resolve symlinks as they are not supported in in-memory file
489
  /// system.
490
  std::error_code getRealPath(const Twine &Path,
491
                              SmallVectorImpl<char> &Output) const override;
492
  std::error_code isLocal(const Twine &Path, bool &Result) override;
493
  std::error_code setCurrentWorkingDirectory(const Twine &Path) override;
494
};
495
496
/// Get a globally unique ID for a virtual file or directory.
497
llvm::sys::fs::UniqueID getNextVirtualUniqueID();
498
499
/// Gets a \p FileSystem for a virtual file system described in YAML
500
/// format.
501
IntrusiveRefCntPtr<FileSystem>
502
getVFSFromYAML(std::unique_ptr<llvm::MemoryBuffer> Buffer,
503
               llvm::SourceMgr::DiagHandlerTy DiagHandler,
504
               StringRef YAMLFilePath, void *DiagContext = nullptr,
505
               IntrusiveRefCntPtr<FileSystem> ExternalFS = getRealFileSystem());
506
507
struct YAMLVFSEntry {
508
  template <typename T1, typename T2>
509
  YAMLVFSEntry(T1 &&VPath, T2 &&RPath)
510
540
      : VPath(std::forward<T1>(VPath)), RPath(std::forward<T2>(RPath)) {}
llvm::vfs::YAMLVFSEntry::YAMLVFSEntry<char const*, llvm::StringRef>(char const*&&, llvm::StringRef&&)
Line
Count
Source
510
2
      : VPath(std::forward<T1>(VPath)), RPath(std::forward<T2>(RPath)) {}
llvm::vfs::YAMLVFSEntry::YAMLVFSEntry<llvm::StringRef&, llvm::StringRef&>(llvm::StringRef&&&, llvm::StringRef&&&)
Line
Count
Source
510
538
      : VPath(std::forward<T1>(VPath)), RPath(std::forward<T2>(RPath)) {}
511
  std::string VPath;
512
  std::string RPath;
513
};
514
515
class VFSFromYamlDirIterImpl;
516
class RedirectingFileSystemParser;
517
518
/// A virtual file system parsed from a YAML file.
519
///
520
/// Currently, this class allows creating virtual directories and mapping
521
/// virtual file paths to existing external files, available in \c ExternalFS.
522
///
523
/// The basic structure of the parsed file is:
524
/// \verbatim
525
/// {
526
///   'version': <version number>,
527
///   <optional configuration>
528
///   'roots': [
529
///              <directory entries>
530
///            ]
531
/// }
532
/// \endverbatim
533
///
534
/// All configuration options are optional.
535
///   'case-sensitive': <boolean, default=true>
536
///   'use-external-names': <boolean, default=true>
537
///   'overlay-relative': <boolean, default=false>
538
///   'fallthrough': <boolean, default=true>
539
///
540
/// Virtual directories are represented as
541
/// \verbatim
542
/// {
543
///   'type': 'directory',
544
///   'name': <string>,
545
///   'contents': [ <file or directory entries> ]
546
/// }
547
/// \endverbatim
548
///
549
/// The default attributes for virtual directories are:
550
/// \verbatim
551
/// MTime = now() when created
552
/// Perms = 0777
553
/// User = Group = 0
554
/// Size = 0
555
/// UniqueID = unspecified unique value
556
/// \endverbatim
557
///
558
/// Re-mapped files are represented as
559
/// \verbatim
560
/// {
561
///   'type': 'file',
562
///   'name': <string>,
563
///   'use-external-name': <boolean> # Optional
564
///   'external-contents': <path to external file>
565
/// }
566
/// \endverbatim
567
///
568
/// and inherit their attributes from the external contents.
569
///
570
/// In both cases, the 'name' field may contain multiple path components (e.g.
571
/// /path/to/file). However, any directory that contains more than one child
572
/// must be uniquely represented by a directory entry.
573
class RedirectingFileSystem : public vfs::FileSystem {
574
public:
575
  enum EntryKind { EK_Directory, EK_File };
576
577
  /// A single file or directory in the VFS.
578
  class Entry {
579
    EntryKind Kind;
580
    std::string Name;
581
582
  public:
583
3.17k
    Entry(EntryKind K, StringRef Name) : Kind(K), Name(Name) {}
584
2.99k
    virtual ~Entry() = default;
585
586
26.9k
    StringRef getName() const { return Name; }
587
28.1k
    EntryKind getKind() const { return Kind; }
588
  };
589
590
  class RedirectingDirectoryEntry : public Entry {
591
    std::vector<std::unique_ptr<Entry>> Contents;
592
    Status S;
593
594
  public:
595
    RedirectingDirectoryEntry(StringRef Name,
596
                              std::vector<std::unique_ptr<Entry>> Contents,
597
                              Status S)
598
        : Entry(EK_Directory, Name), Contents(std::move(Contents)),
599
1.31k
          S(std::move(S)) {}
600
    RedirectingDirectoryEntry(StringRef Name, Status S)
601
1.06k
        : Entry(EK_Directory, Name), S(std::move(S)) {}
602
603
382
    Status getStatus() { return S; }
604
605
1.38k
    void addContent(std::unique_ptr<Entry> Content) {
606
1.38k
      Contents.push_back(std::move(Content));
607
1.38k
    }
608
609
989
    Entry *getLastContent() const { return Contents.back().get(); }
610
611
    using iterator = decltype(Contents)::iterator;
612
613
23.2k
    iterator contents_begin() { return Contents.begin(); }
614
23.2k
    iterator contents_end() { return Contents.end(); }
615
616
25.3k
    static bool classof(const Entry *E) { return E->getKind() == EK_Directory; }
617
  };
618
619
  class RedirectingFileEntry : public Entry {
620
  public:
621
    enum NameKind { NK_NotSet, NK_External, NK_Virtual };
622
623
  private:
624
    std::string ExternalContentsPath;
625
    NameKind UseName;
626
627
  public:
628
    RedirectingFileEntry(StringRef Name, StringRef ExternalContentsPath,
629
                         NameKind UseName)
630
        : Entry(EK_File, Name), ExternalContentsPath(ExternalContentsPath),
631
794
          UseName(UseName) {}
632
633
591
    StringRef getExternalContentsPath() const { return ExternalContentsPath; }
634
635
    /// whether to use the external path as the name for this file.
636
188
    bool useExternalName(bool GlobalUseExternalName) const {
637
188
      return UseName == NK_NotSet ? 
GlobalUseExternalName184
638
188
                                  : 
(UseName == NK_External)4
;
639
188
    }
640
641
397
    NameKind getUseName() const { return UseName; }
642
643
1.02k
    static bool classof(const Entry *E) { return E->getKind() == EK_File; }
644
  };
645
646
private:
647
  friend class VFSFromYamlDirIterImpl;
648
  friend class RedirectingFileSystemParser;
649
650
  /// The root(s) of the virtual file system.
651
  std::vector<std::unique_ptr<Entry>> Roots;
652
653
  /// The file system to use for external references.
654
  IntrusiveRefCntPtr<FileSystem> ExternalFS;
655
656
  /// If IsRelativeOverlay is set, this represents the directory
657
  /// path that should be prefixed to each 'external-contents' entry
658
  /// when reading from YAML files.
659
  std::string ExternalContentsPrefixDir;
660
661
  /// @name Configuration
662
  /// @{
663
664
  /// Whether to perform case-sensitive comparisons.
665
  ///
666
  /// Currently, case-insensitive matching only works correctly with ASCII.
667
  bool CaseSensitive = true;
668
669
  /// IsRelativeOverlay marks whether a ExternalContentsPrefixDir path must
670
  /// be prefixed in every 'external-contents' when reading from YAML files.
671
  bool IsRelativeOverlay = false;
672
673
  /// Whether to use to use the value of 'external-contents' for the
674
  /// names of files.  This global value is overridable on a per-file basis.
675
  bool UseExternalNames = true;
676
677
  /// Whether to attempt a file lookup in external file system after it wasn't
678
  /// found in VFS.
679
  bool IsFallthrough = true;
680
  /// @}
681
682
  /// Virtual file paths and external files could be canonicalized without "..",
683
  /// "." and "./" in their paths. FIXME: some unittests currently fail on
684
  /// win32 when using remove_dots and remove_leading_dotslash on paths.
685
  bool UseCanonicalizedPaths =
686
#ifdef _WIN32
687
      false;
688
#else
689
      true;
690
#endif
691
692
  RedirectingFileSystem(IntrusiveRefCntPtr<FileSystem> ExternalFS)
693
109
      : ExternalFS(std::move(ExternalFS)) {}
694
695
  /// Looks up the path <tt>[Start, End)</tt> in \p From, possibly
696
  /// recursing into the contents of \p From if it is a directory.
697
  ErrorOr<Entry *> lookupPath(llvm::sys::path::const_iterator Start,
698
                              llvm::sys::path::const_iterator End,
699
                              Entry *From) const;
700
701
  /// Get the status of a given an \c Entry.
702
  ErrorOr<Status> status(const Twine &Path, Entry *E);
703
704
public:
705
  /// Looks up \p Path in \c Roots.
706
  ErrorOr<Entry *> lookupPath(const Twine &Path) const;
707
708
  /// Parses \p Buffer, which is expected to be in YAML format and
709
  /// returns a virtual file system representing its contents.
710
  static RedirectingFileSystem *
711
  create(std::unique_ptr<MemoryBuffer> Buffer,
712
         SourceMgr::DiagHandlerTy DiagHandler, StringRef YAMLFilePath,
713
         void *DiagContext, IntrusiveRefCntPtr<FileSystem> ExternalFS);
714
715
  ErrorOr<Status> status(const Twine &Path) override;
716
  ErrorOr<std::unique_ptr<File>> openFileForRead(const Twine &Path) override;
717
718
  std::error_code getRealPath(const Twine &Path,
719
                              SmallVectorImpl<char> &Output) const override;
720
721
  llvm::ErrorOr<std::string> getCurrentWorkingDirectory() const override;
722
723
  std::error_code setCurrentWorkingDirectory(const Twine &Path) override;
724
725
  std::error_code isLocal(const Twine &Path, bool &Result) override;
726
727
  directory_iterator dir_begin(const Twine &Dir, std::error_code &EC) override;
728
729
  void setExternalContentsPrefixDir(StringRef PrefixDir);
730
731
  StringRef getExternalContentsPrefixDir() const;
732
733
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
734
  LLVM_DUMP_METHOD void dump() const;
735
  LLVM_DUMP_METHOD void dumpEntry(Entry *E, int NumSpaces = 0) const;
736
#endif
737
};
738
739
/// Collect all pairs of <virtual path, real path> entries from the
740
/// \p YAMLFilePath. This is used by the module dependency collector to forward
741
/// the entries into the reproducer output VFS YAML file.
742
void collectVFSFromYAML(
743
    std::unique_ptr<llvm::MemoryBuffer> Buffer,
744
    llvm::SourceMgr::DiagHandlerTy DiagHandler, StringRef YAMLFilePath,
745
    SmallVectorImpl<YAMLVFSEntry> &CollectedEntries,
746
    void *DiagContext = nullptr,
747
    IntrusiveRefCntPtr<FileSystem> ExternalFS = getRealFileSystem());
748
749
class YAMLVFSWriter {
750
  std::vector<YAMLVFSEntry> Mappings;
751
  Optional<bool> IsCaseSensitive;
752
  Optional<bool> IsOverlayRelative;
753
  Optional<bool> UseExternalNames;
754
  std::string OverlayDir;
755
756
public:
757
25
  YAMLVFSWriter() = default;
758
759
  void addFileMapping(StringRef VirtualPath, StringRef RealPath);
760
761
17
  void setCaseSensitivity(bool CaseSensitive) {
762
17
    IsCaseSensitive = CaseSensitive;
763
17
  }
764
765
16
  void setUseExternalNames(bool UseExtNames) { UseExternalNames = UseExtNames; }
766
767
16
  void setOverlayDir(StringRef OverlayDirectory) {
768
16
    IsOverlayRelative = true;
769
16
    OverlayDir.assign(OverlayDirectory.str());
770
16
  }
771
772
0
  const std::vector<YAMLVFSEntry> &getMappings() const { return Mappings; }
773
774
  void write(llvm::raw_ostream &OS);
775
};
776
777
} // namespace vfs
778
} // namespace llvm
779
780
#endif // LLVM_SUPPORT_VIRTUALFILESYSTEM_H