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1//===- llvm/Support/Windows/Path.inc - Windows Path Impl --------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements the Windows specific implementation of the Path API.10//11//===----------------------------------------------------------------------===//12 13//===----------------------------------------------------------------------===//14//=== WARNING: Implementation here must contain only generic Windows code that15//===          is guaranteed to work on *all* Windows variants.16//===----------------------------------------------------------------------===//17 18#include "llvm/ADT/STLExtras.h"19#include "llvm/Support/ConvertUTF.h"20#include "llvm/Support/WindowsError.h"21#include <fcntl.h>22#include <sys/stat.h>23#include <sys/types.h>24 25// These two headers must be included last, and make sure shlobj is required26// after Windows.h to make sure it picks up our definition of _WIN32_WINNT27#include "llvm/Support/Windows/WindowsSupport.h"28#include <shellapi.h>29#include <shlobj.h>30#include <winioctl.h>31 32#undef max33 34// MinGW doesn't define this.35#ifndef _ERRNO_T_DEFINED36#define _ERRNO_T_DEFINED37typedef int errno_t;38#endif39 40#ifdef _MSC_VER41#pragma comment(lib, "advapi32.lib") // This provides CryptAcquireContextW.42#pragma comment(lib, "ole32.lib")    // This provides CoTaskMemFree43#endif44 45using namespace llvm;46 47using llvm::sys::windows::CurCPToUTF16;48using llvm::sys::windows::UTF16ToUTF8;49using llvm::sys::windows::UTF8ToUTF16;50using llvm::sys::windows::widenPath;51 52static bool is_separator(const wchar_t value) {53  switch (value) {54  case L'\\':55  case L'/':56    return true;57  default:58    return false;59  }60}61 62namespace llvm {63namespace sys {64namespace windows {65 66// Convert a UTF-8 path to UTF-16. Also, if the absolute equivalent of the path67// is longer than the limit that the Win32 Unicode File API can tolerate, make68// it an absolute normalized path prefixed by '\\?\'.69std::error_code widenPath(const Twine &Path8, SmallVectorImpl<wchar_t> &Path16,70                          size_t MaxPathLen) {71  assert(MaxPathLen <= MAX_PATH);72 73  // Several operations would convert Path8 to SmallString; more efficient to do74  // it once up front.75  SmallString<MAX_PATH> Path8Str;76  Path8.toVector(Path8Str);77 78  // If the path is a long path, mangled into forward slashes, normalize79  // back to backslashes here.80  if (Path8Str.starts_with("//?/"))81    llvm::sys::path::native(Path8Str, path::Style::windows_backslash);82 83  if (std::error_code EC = UTF8ToUTF16(Path8Str, Path16))84    return EC;85 86  const bool IsAbsolute = llvm::sys::path::is_absolute(Path8);87  size_t CurPathLen;88  if (IsAbsolute)89    CurPathLen = 0; // No contribution from current_path needed.90  else {91    CurPathLen = ::GetCurrentDirectoryW(92        0, NULL); // Returns the size including the null terminator.93    if (CurPathLen == 0)94      return mapWindowsError(::GetLastError());95  }96 97  const char *const LongPathPrefix = "\\\\?\\";98 99  if ((Path16.size() + CurPathLen) < MaxPathLen ||100      Path8Str.starts_with(LongPathPrefix))101    return std::error_code();102 103  if (!IsAbsolute) {104    if (std::error_code EC = llvm::sys::fs::make_absolute(Path8Str))105      return EC;106  }107 108  // Remove '.' and '..' because long paths treat these as real path components.109  // Explicitly use the backslash form here, as we're prepending the \\?\110  // prefix.111  llvm::sys::path::native(Path8Str, path::Style::windows);112  llvm::sys::path::remove_dots(Path8Str, true, path::Style::windows);113 114  const StringRef RootName = llvm::sys::path::root_name(Path8Str);115  assert(!RootName.empty() &&116         "Root name cannot be empty for an absolute path!");117 118  SmallString<2 * MAX_PATH> FullPath(LongPathPrefix);119  if (RootName[1] != ':') { // Check if UNC.120    FullPath.append("UNC\\");121    FullPath.append(Path8Str.begin() + 2, Path8Str.end());122  } else {123    FullPath.append(Path8Str);124  }125 126  return UTF8ToUTF16(FullPath, Path16);127}128 129} // end namespace windows130 131namespace fs {132 133const file_t kInvalidFile = INVALID_HANDLE_VALUE;134 135std::string getMainExecutable(const char *argv0, void *MainExecAddr) {136  SmallVector<wchar_t, MAX_PATH> PathName;137  PathName.resize_for_overwrite(PathName.capacity());138  DWORD Size = ::GetModuleFileNameW(NULL, PathName.data(), PathName.size());139 140  // A zero return value indicates a failure other than insufficient space.141  if (Size == 0)142    return "";143 144  // Insufficient space is determined by a return value equal to the size of145  // the buffer passed in.146  if (Size == PathName.capacity())147    return "";148 149  // On success, GetModuleFileNameW returns the number of characters written to150  // the buffer not including the NULL terminator.151  PathName.truncate(Size);152 153  // Convert the result from UTF-16 to UTF-8.154  SmallVector<char, MAX_PATH> PathNameUTF8;155  if (UTF16ToUTF8(PathName.data(), PathName.size(), PathNameUTF8))156    return "";157 158  llvm::sys::path::make_preferred(PathNameUTF8);159 160  SmallString<256> RealPath;161  sys::fs::real_path(PathNameUTF8, RealPath);162  if (RealPath.size())163    return std::string(RealPath);164  return std::string(PathNameUTF8.data());165}166 167UniqueID file_status::getUniqueID() const {168  return UniqueID(VolumeSerialNumber, PathHash);169}170 171ErrorOr<space_info> disk_space(const Twine &Path) {172  ULARGE_INTEGER Avail, Total, Free;173  if (!::GetDiskFreeSpaceExA(Path.str().c_str(), &Avail, &Total, &Free))174    return mapWindowsError(::GetLastError());175  space_info SpaceInfo;176  SpaceInfo.capacity =177      (static_cast<uint64_t>(Total.HighPart) << 32) + Total.LowPart;178  SpaceInfo.free = (static_cast<uint64_t>(Free.HighPart) << 32) + Free.LowPart;179  SpaceInfo.available =180      (static_cast<uint64_t>(Avail.HighPart) << 32) + Avail.LowPart;181  return SpaceInfo;182}183 184TimePoint<> basic_file_status::getLastAccessedTime() const {185  FILETIME Time;186  Time.dwLowDateTime = LastAccessedTimeLow;187  Time.dwHighDateTime = LastAccessedTimeHigh;188  return toTimePoint(Time);189}190 191TimePoint<> basic_file_status::getLastModificationTime() const {192  FILETIME Time;193  Time.dwLowDateTime = LastWriteTimeLow;194  Time.dwHighDateTime = LastWriteTimeHigh;195  return toTimePoint(Time);196}197 198uint32_t file_status::getLinkCount() const { return NumLinks; }199 200std::error_code current_path(SmallVectorImpl<char> &result) {201  SmallVector<wchar_t, MAX_PATH> cur_path;202  DWORD len = MAX_PATH;203 204  do {205    cur_path.resize_for_overwrite(len);206    len = ::GetCurrentDirectoryW(cur_path.size(), cur_path.data());207 208    // A zero return value indicates a failure other than insufficient space.209    if (len == 0)210      return mapWindowsError(::GetLastError());211 212    // If there's insufficient space, the len returned is larger than the len213    // given.214  } while (len > cur_path.size());215 216  // On success, GetCurrentDirectoryW returns the number of characters not217  // including the null-terminator.218  cur_path.truncate(len);219 220  if (std::error_code EC =221          UTF16ToUTF8(cur_path.begin(), cur_path.size(), result))222    return EC;223 224  llvm::sys::path::make_preferred(result);225  return std::error_code();226}227 228std::error_code set_current_path(const Twine &path) {229  // Convert to utf-16.230  SmallVector<wchar_t, 128> wide_path;231  if (std::error_code ec = widenPath(path, wide_path))232    return ec;233 234  if (!::SetCurrentDirectoryW(wide_path.begin()))235    return mapWindowsError(::GetLastError());236 237  return std::error_code();238}239 240std::error_code create_directory(const Twine &path, bool IgnoreExisting,241                                 perms Perms) {242  SmallVector<wchar_t, 128> path_utf16;243 244  // CreateDirectoryW has a lower maximum path length as it must leave room for245  // an 8.3 filename.246  if (std::error_code ec = widenPath(path, path_utf16, MAX_PATH - 12))247    return ec;248 249  if (!::CreateDirectoryW(path_utf16.begin(), NULL)) {250    DWORD LastError = ::GetLastError();251    if (LastError != ERROR_ALREADY_EXISTS || !IgnoreExisting)252      return mapWindowsError(LastError);253  }254 255  return std::error_code();256}257 258// We can't use symbolic links for windows.259std::error_code create_link(const Twine &to, const Twine &from) {260  // Convert to utf-16.261  SmallVector<wchar_t, 128> wide_from;262  SmallVector<wchar_t, 128> wide_to;263  if (std::error_code ec = widenPath(from, wide_from))264    return ec;265  if (std::error_code ec = widenPath(to, wide_to))266    return ec;267 268  if (!::CreateHardLinkW(wide_from.begin(), wide_to.begin(), NULL))269    return mapWindowsError(::GetLastError());270 271  return std::error_code();272}273 274std::error_code create_hard_link(const Twine &to, const Twine &from) {275  return create_link(to, from);276}277 278std::error_code remove(const Twine &path, bool IgnoreNonExisting) {279  SmallVector<wchar_t, 128> path_utf16;280 281  if (std::error_code ec = widenPath(path, path_utf16))282    return ec;283 284  // We don't know whether this is a file or a directory, and remove() can285  // accept both. The usual way to delete a file or directory is to use one of286  // the DeleteFile or RemoveDirectory functions, but that requires you to know287  // which one it is. We could stat() the file to determine that, but that would288  // cost us additional system calls, which can be slow in a directory289  // containing a large number of files. So instead we call CreateFile directly.290  // The important part is the FILE_FLAG_DELETE_ON_CLOSE flag, which causes the291  // file to be deleted once it is closed. We also use the flags292  // FILE_FLAG_BACKUP_SEMANTICS (which allows us to open directories), and293  // FILE_FLAG_OPEN_REPARSE_POINT (don't follow symlinks).294  ScopedFileHandle h(::CreateFileW(295      c_str(path_utf16), DELETE,296      FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,297      OPEN_EXISTING,298      FILE_ATTRIBUTE_NORMAL | FILE_FLAG_BACKUP_SEMANTICS |299          FILE_FLAG_OPEN_REPARSE_POINT | FILE_FLAG_DELETE_ON_CLOSE,300      NULL));301  if (!h) {302    std::error_code EC = mapWindowsError(::GetLastError());303    if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)304      return EC;305  }306 307  return std::error_code();308}309 310static std::error_code is_local_internal(SmallVectorImpl<wchar_t> &Path,311                                         bool &Result) {312  SmallVector<wchar_t, 128> VolumePath;313  size_t Len = 128;314  while (true) {315    VolumePath.resize(Len);316    BOOL Success =317        ::GetVolumePathNameW(Path.data(), VolumePath.data(), VolumePath.size());318 319    if (Success)320      break;321 322    DWORD Err = ::GetLastError();323    if (Err != ERROR_INSUFFICIENT_BUFFER)324      return mapWindowsError(Err);325 326    Len *= 2;327  }328  // If the output buffer has exactly enough space for the path name, but not329  // the null terminator, it will leave the output unterminated.  Push a null330  // terminator onto the end to ensure that this never happens.331  VolumePath.push_back(L'\0');332  VolumePath.truncate(wcslen(VolumePath.data()));333  const wchar_t *P = VolumePath.data();334 335  UINT Type = ::GetDriveTypeW(P);336  switch (Type) {337  case DRIVE_FIXED:338    Result = true;339    return std::error_code();340  case DRIVE_REMOTE:341  case DRIVE_CDROM:342  case DRIVE_RAMDISK:343  case DRIVE_REMOVABLE:344    Result = false;345    return std::error_code();346  default:347    return make_error_code(errc::no_such_file_or_directory);348  }349  llvm_unreachable("Unreachable!");350}351 352std::error_code is_local(const Twine &path, bool &result) {353  if (!llvm::sys::fs::exists(path) || !llvm::sys::path::has_root_path(path))354    return make_error_code(errc::no_such_file_or_directory);355 356  SmallString<128> Storage;357  StringRef P = path.toStringRef(Storage);358 359  // Convert to utf-16.360  SmallVector<wchar_t, 128> WidePath;361  if (std::error_code ec = widenPath(P, WidePath))362    return ec;363  return is_local_internal(WidePath, result);364}365 366static std::error_code realPathFromHandle(HANDLE H,367                                          SmallVectorImpl<wchar_t> &Buffer,368                                          DWORD flags = VOLUME_NAME_DOS) {369  Buffer.resize_for_overwrite(Buffer.capacity());370  DWORD CountChars = ::GetFinalPathNameByHandleW(371      H, Buffer.begin(), Buffer.capacity(), FILE_NAME_NORMALIZED | flags);372  if (CountChars && CountChars >= Buffer.capacity()) {373    // The buffer wasn't big enough, try again.  In this case the return value374    // *does* indicate the size of the null terminator.375    Buffer.resize_for_overwrite(CountChars);376    CountChars = ::GetFinalPathNameByHandleW(H, Buffer.begin(), Buffer.size(),377                                             FILE_NAME_NORMALIZED | flags);378  }379  Buffer.truncate(CountChars);380  if (CountChars == 0)381    return mapWindowsError(GetLastError());382  return std::error_code();383}384 385static std::error_code realPathFromHandle(HANDLE H,386                                          SmallVectorImpl<char> &RealPath) {387  RealPath.clear();388  SmallVector<wchar_t, MAX_PATH> Buffer;389  if (std::error_code EC = realPathFromHandle(H, Buffer))390    return EC;391 392  // Strip the \\?\ prefix. We don't want it ending up in output, and such393  // paths don't get canonicalized by file APIs.394  wchar_t *Data = Buffer.data();395  DWORD CountChars = Buffer.size();396  if (CountChars >= 8 && ::memcmp(Data, L"\\\\?\\UNC\\", 16) == 0) {397    // Convert \\?\UNC\foo\bar to \\foo\bar398    CountChars -= 6;399    Data += 6;400    Data[0] = '\\';401  } else if (CountChars >= 4 && ::memcmp(Data, L"\\\\?\\", 8) == 0) {402    // Convert \\?\c:\foo to c:\foo403    CountChars -= 4;404    Data += 4;405  }406 407  // Convert the result from UTF-16 to UTF-8.408  if (std::error_code EC = UTF16ToUTF8(Data, CountChars, RealPath))409    return EC;410 411  llvm::sys::path::make_preferred(RealPath);412  return std::error_code();413}414 415std::error_code is_local(int FD, bool &Result) {416  SmallVector<wchar_t, 128> FinalPath;417  HANDLE Handle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));418 419  if (std::error_code EC = realPathFromHandle(Handle, FinalPath))420    return EC;421 422  return is_local_internal(FinalPath, Result);423}424 425static std::error_code setDeleteDisposition(HANDLE Handle, bool Delete) {426  // Clear the FILE_DISPOSITION_INFO flag first, before checking if it's a427  // network file. On Windows 7 the function realPathFromHandle() below fails428  // if the FILE_DISPOSITION_INFO flag was already set to 'DeleteFile = true' by429  // a prior call.430  FILE_DISPOSITION_INFO Disposition;431  Disposition.DeleteFile = false;432  if (!SetFileInformationByHandle(Handle, FileDispositionInfo, &Disposition,433                                  sizeof(Disposition)))434    return mapWindowsError(::GetLastError());435  if (!Delete)436    return std::error_code();437 438  // Check if the file is on a network (non-local) drive. If so, don't439  // continue when DeleteFile is true, since it prevents opening the file for440  // writes.441  SmallVector<wchar_t, 128> FinalPath;442  if (std::error_code EC = realPathFromHandle(Handle, FinalPath))443    return EC;444 445  bool IsLocal;446  if (std::error_code EC = is_local_internal(FinalPath, IsLocal))447    return EC;448 449  if (!IsLocal)450    return errc::not_supported;451 452  // The file is on a local drive, we can safely set FILE_DISPOSITION_INFO's453  // flag.454  Disposition.DeleteFile = true;455  if (!SetFileInformationByHandle(Handle, FileDispositionInfo, &Disposition,456                                  sizeof(Disposition)))457    return mapWindowsError(::GetLastError());458  return std::error_code();459}460 461static std::error_code rename_internal(HANDLE FromHandle, const Twine &To,462                                       bool ReplaceIfExists) {463  SmallVector<wchar_t, 0> ToWide;464  if (auto EC = widenPath(To, ToWide))465    return EC;466 467  std::vector<char> RenameInfoBuf(sizeof(FILE_RENAME_INFO) - sizeof(wchar_t) +468                                  (ToWide.size() * sizeof(wchar_t)));469  FILE_RENAME_INFO &RenameInfo =470      *reinterpret_cast<FILE_RENAME_INFO *>(RenameInfoBuf.data());471  RenameInfo.ReplaceIfExists = ReplaceIfExists;472  RenameInfo.RootDirectory = 0;473  RenameInfo.FileNameLength = ToWide.size() * sizeof(wchar_t);474  std::copy(ToWide.begin(), ToWide.end(), &RenameInfo.FileName[0]);475 476  SetLastError(ERROR_SUCCESS);477  if (!SetFileInformationByHandle(FromHandle, FileRenameInfo, &RenameInfo,478                                  RenameInfoBuf.size())) {479    unsigned Error = GetLastError();480    if (Error == ERROR_SUCCESS)481      Error = ERROR_CALL_NOT_IMPLEMENTED; // Wine doesn't always set error code.482    return mapWindowsError(Error);483  }484 485  return std::error_code();486}487 488static std::error_code rename_handle(HANDLE FromHandle, const Twine &To) {489  SmallVector<wchar_t, 128> WideTo;490  if (std::error_code EC = widenPath(To, WideTo))491    return EC;492 493  // We normally expect this loop to succeed after a few iterations. If it494  // requires more than 200 tries, it's more likely that the failures are due to495  // a true error, so stop trying.496  for (unsigned Retry = 0; Retry != 200; ++Retry) {497    auto EC = rename_internal(FromHandle, To, true);498 499    if (EC ==500        std::error_code(ERROR_CALL_NOT_IMPLEMENTED, std::system_category())) {501      // Wine doesn't support SetFileInformationByHandle in rename_internal.502      // Fall back to MoveFileEx.503      SmallVector<wchar_t, MAX_PATH> WideFrom;504      if (std::error_code EC2 = realPathFromHandle(FromHandle, WideFrom))505        return EC2;506      if (::MoveFileExW(WideFrom.begin(), WideTo.begin(),507                        MOVEFILE_REPLACE_EXISTING))508        return std::error_code();509      return mapWindowsError(GetLastError());510    }511 512    if (!EC || EC != errc::permission_denied)513      return EC;514 515    // The destination file probably exists and is currently open in another516    // process, either because the file was opened without FILE_SHARE_DELETE or517    // it is mapped into memory (e.g. using MemoryBuffer). Rename it in order to518    // move it out of the way of the source file. Use FILE_FLAG_DELETE_ON_CLOSE519    // to arrange for the destination file to be deleted when the other process520    // closes it.521    ScopedFileHandle ToHandle(522        ::CreateFileW(WideTo.begin(), GENERIC_READ | DELETE,523                      FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,524                      NULL, OPEN_EXISTING,525                      FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE, NULL));526    if (!ToHandle) {527      auto EC = mapWindowsError(GetLastError());528      // Another process might have raced with us and moved the existing file529      // out of the way before we had a chance to open it. If that happens, try530      // to rename the source file again.531      if (EC == errc::no_such_file_or_directory)532        continue;533      return EC;534    }535 536    BY_HANDLE_FILE_INFORMATION FI;537    if (!GetFileInformationByHandle(ToHandle, &FI))538      return mapWindowsError(GetLastError());539 540    // Try to find a unique new name for the destination file.541    for (unsigned UniqueId = 0; UniqueId != 200; ++UniqueId) {542      std::string TmpFilename = (To + ".tmp" + utostr(UniqueId)).str();543      if (auto EC = rename_internal(ToHandle, TmpFilename, false)) {544        if (EC == errc::file_exists || EC == errc::permission_denied) {545          // Again, another process might have raced with us and moved the file546          // before we could move it. Check whether this is the case, as it547          // might have caused the permission denied error. If that was the548          // case, we don't need to move it ourselves.549          ScopedFileHandle ToHandle2(::CreateFileW(550              WideTo.begin(), 0,551              FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,552              OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL));553          if (!ToHandle2) {554            auto EC = mapWindowsError(GetLastError());555            if (EC == errc::no_such_file_or_directory)556              break;557            return EC;558          }559          BY_HANDLE_FILE_INFORMATION FI2;560          if (!GetFileInformationByHandle(ToHandle2, &FI2))561            return mapWindowsError(GetLastError());562          if (FI.nFileIndexHigh != FI2.nFileIndexHigh ||563              FI.nFileIndexLow != FI2.nFileIndexLow ||564              FI.dwVolumeSerialNumber != FI2.dwVolumeSerialNumber)565            break;566          continue;567        }568        return EC;569      }570      break;571    }572 573    // Okay, the old destination file has probably been moved out of the way at574    // this point, so try to rename the source file again. Still, another575    // process might have raced with us to create and open the destination576    // file, so we need to keep doing this until we succeed.577  }578 579  // The most likely root cause.580  return errc::permission_denied;581}582 583std::error_code rename(const Twine &From, const Twine &To) {584  // Convert to utf-16.585  SmallVector<wchar_t, 128> WideFrom;586  if (std::error_code EC = widenPath(From, WideFrom))587    return EC;588 589  ScopedFileHandle FromHandle;590  // Retry this a few times to defeat badly behaved file system scanners.591  for (unsigned Retry = 0; Retry != 200; ++Retry) {592    if (Retry != 0)593      ::Sleep(10);594    FromHandle =595        ::CreateFileW(WideFrom.begin(), GENERIC_READ | DELETE,596                      FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,597                      NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);598    if (FromHandle)599      break;600 601    // We don't want to loop if the file doesn't exist.602    auto EC = mapWindowsError(GetLastError());603    if (EC == errc::no_such_file_or_directory)604      return EC;605  }606  if (!FromHandle)607    return mapWindowsError(GetLastError());608 609  return rename_handle(FromHandle, To);610}611 612std::error_code resize_file(int FD, uint64_t Size) {613#ifdef HAVE__CHSIZE_S614  errno_t error = ::_chsize_s(FD, Size);615#else616  errno_t error = ::_chsize(FD, Size);617#endif618  return std::error_code(error, std::generic_category());619}620 621std::error_code resize_file_sparse(int FD, uint64_t Size) {622  HANDLE hFile = reinterpret_cast<HANDLE>(::_get_osfhandle(FD));623  DWORD temp;624  if (!DeviceIoControl(hFile, FSCTL_SET_SPARSE, NULL, 0, NULL, 0, &temp,625                       NULL)) {626    return mapWindowsError(GetLastError());627  }628  LARGE_INTEGER liSize;629  liSize.QuadPart = Size;630  if (!SetFilePointerEx(hFile, liSize, NULL, FILE_BEGIN) ||631      !SetEndOfFile(hFile)) {632    return mapWindowsError(GetLastError());633  }634  return std::error_code();635}636 637std::error_code access(const Twine &Path, AccessMode Mode) {638  SmallVector<wchar_t, 128> PathUtf16;639 640  if (std::error_code EC = widenPath(Path, PathUtf16))641    return EC;642 643  DWORD Attributes = ::GetFileAttributesW(PathUtf16.begin());644 645  if (Attributes == INVALID_FILE_ATTRIBUTES) {646    // Avoid returning unexpected error codes when querying for existence.647    if (Mode == AccessMode::Exist)648      return errc::no_such_file_or_directory;649 650    // See if the file didn't actually exist.651    DWORD LastError = ::GetLastError();652    if (LastError != ERROR_FILE_NOT_FOUND && LastError != ERROR_PATH_NOT_FOUND)653      return mapWindowsError(LastError);654    return errc::no_such_file_or_directory;655  }656 657  if (Mode == AccessMode::Write && (Attributes & FILE_ATTRIBUTE_READONLY))658    return errc::permission_denied;659 660  if (Mode == AccessMode::Execute && (Attributes & FILE_ATTRIBUTE_DIRECTORY))661    return errc::permission_denied;662 663  return std::error_code();664}665 666bool can_execute(const Twine &Path) {667  return !access(Path, AccessMode::Execute) ||668         !access(Path + ".exe", AccessMode::Execute);669}670 671bool equivalent(file_status A, file_status B) {672  assert(status_known(A) && status_known(B));673  return A.getUniqueID() == B.getUniqueID();674}675 676std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {677  file_status fsA, fsB;678  if (std::error_code ec = status(A, fsA))679    return ec;680  if (std::error_code ec = status(B, fsB))681    return ec;682  result = equivalent(fsA, fsB);683  return std::error_code();684}685 686static bool isReservedName(StringRef path) {687  // This list of reserved names comes from MSDN, at:688  // http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx689  static const char *const sReservedNames[] = {690      "nul",  "con",  "prn",  "aux",  "com1", "com2", "com3", "com4",691      "com5", "com6", "com7", "com8", "com9", "lpt1", "lpt2", "lpt3",692      "lpt4", "lpt5", "lpt6", "lpt7", "lpt8", "lpt9"};693 694  // First, check to see if this is a device namespace, which always695  // starts with \\.\, since device namespaces are not legal file paths.696  if (path.starts_with("\\\\.\\"))697    return true;698 699  // Then compare against the list of ancient reserved names.700  for (size_t i = 0; i < std::size(sReservedNames); ++i) {701    if (path.equals_insensitive(sReservedNames[i]))702      return true;703  }704 705  // The path isn't what we consider reserved.706  return false;707}708 709static file_type file_type_from_attrs(DWORD Attrs) {710  return (Attrs & FILE_ATTRIBUTE_DIRECTORY) ? file_type::directory_file711                                            : file_type::regular_file;712}713 714static perms perms_from_attrs(DWORD Attrs) {715  return (Attrs & FILE_ATTRIBUTE_READONLY) ? (all_read | all_exe) : all_all;716}717 718static std::error_code getStatus(HANDLE FileHandle, file_status &Result) {719  SmallVector<wchar_t, MAX_PATH> ntPath;720  if (FileHandle == INVALID_HANDLE_VALUE)721    goto handle_status_error;722 723  switch (::GetFileType(FileHandle)) {724  default:725    llvm_unreachable("Don't know anything about this file type");726  case FILE_TYPE_UNKNOWN: {727    DWORD Err = ::GetLastError();728    if (Err != NO_ERROR)729      return mapWindowsError(Err);730    Result = file_status(file_type::type_unknown);731    return std::error_code();732  }733  case FILE_TYPE_DISK:734    break;735  case FILE_TYPE_CHAR:736    Result = file_status(file_type::character_file);737    return std::error_code();738  case FILE_TYPE_PIPE:739    Result = file_status(file_type::fifo_file);740    return std::error_code();741  }742 743  BY_HANDLE_FILE_INFORMATION Info;744  if (!::GetFileInformationByHandle(FileHandle, &Info))745    goto handle_status_error;746 747  // File indices aren't necessarily stable after closing the file handle;748  // instead hash a canonicalized path.749  //750  // For getting a canonical path to the file, call GetFinalPathNameByHandleW751  // with VOLUME_NAME_NT. We don't really care exactly what the path looks752  // like here, as long as it is canonical (e.g. doesn't differentiate between753  // whether a file was referred to with upper/lower case names originally).754  // The default format with VOLUME_NAME_DOS doesn't work with all file system755  // drivers, such as ImDisk. (See756  // https://github.com/rust-lang/rust/pull/86447.)757  uint64_t PathHash;758  if (std::error_code EC =759          realPathFromHandle(FileHandle, ntPath, VOLUME_NAME_NT)) {760    // If realPathFromHandle failed, fall back on the fields761    // nFileIndex{High,Low} instead. They're not necessarily stable on all file762    // systems as they're only documented as being unique/stable as long as the763    // file handle is open - but they're a decent fallback if we couldn't get764    // the canonical path.765    PathHash = (static_cast<uint64_t>(Info.nFileIndexHigh) << 32ULL) |766               static_cast<uint64_t>(Info.nFileIndexLow);767  } else {768    PathHash = hash_combine_range(ntPath);769  }770 771  Result = file_status(772      file_type_from_attrs(Info.dwFileAttributes),773      perms_from_attrs(Info.dwFileAttributes), Info.nNumberOfLinks,774      Info.ftLastAccessTime.dwHighDateTime, Info.ftLastAccessTime.dwLowDateTime,775      Info.ftLastWriteTime.dwHighDateTime, Info.ftLastWriteTime.dwLowDateTime,776      Info.dwVolumeSerialNumber, Info.nFileSizeHigh, Info.nFileSizeLow,777      PathHash);778  return std::error_code();779 780handle_status_error:781  std::error_code Err = mapLastWindowsError();782  if (Err == std::errc::no_such_file_or_directory)783    Result = file_status(file_type::file_not_found);784  else if (Err == std::errc::permission_denied)785    Result = file_status(file_type::type_unknown);786  else787    Result = file_status(file_type::status_error);788  return Err;789}790 791std::error_code status(const Twine &path, file_status &result, bool Follow) {792  SmallString<128> path_storage;793  SmallVector<wchar_t, 128> path_utf16;794 795  StringRef path8 = path.toStringRef(path_storage);796  if (isReservedName(path8)) {797    result = file_status(file_type::character_file);798    return std::error_code();799  }800 801  if (std::error_code ec = widenPath(path8, path_utf16))802    return ec;803 804  DWORD Flags = FILE_FLAG_BACKUP_SEMANTICS;805  if (!Follow) {806    DWORD attr = ::GetFileAttributesW(path_utf16.begin());807    if (attr == INVALID_FILE_ATTRIBUTES)808      return getStatus(INVALID_HANDLE_VALUE, result);809 810    // Handle reparse points.811    if (attr & FILE_ATTRIBUTE_REPARSE_POINT)812      Flags |= FILE_FLAG_OPEN_REPARSE_POINT;813  }814 815  ScopedFileHandle h(816      ::CreateFileW(path_utf16.begin(), 0, // Attributes only.817                    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,818                    NULL, OPEN_EXISTING, Flags, 0));819  if (!h)820    return getStatus(INVALID_HANDLE_VALUE, result);821 822  return getStatus(h, result);823}824 825std::error_code status(int FD, file_status &Result) {826  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));827  return getStatus(FileHandle, Result);828}829 830std::error_code status(file_t FileHandle, file_status &Result) {831  return getStatus(FileHandle, Result);832}833 834unsigned getUmask() { return 0; }835 836std::error_code setPermissions(const Twine &Path, perms Permissions) {837  SmallVector<wchar_t, 128> PathUTF16;838  if (std::error_code EC = widenPath(Path, PathUTF16))839    return EC;840 841  DWORD Attributes = ::GetFileAttributesW(PathUTF16.begin());842  if (Attributes == INVALID_FILE_ATTRIBUTES)843    return mapWindowsError(GetLastError());844 845  // There are many Windows file attributes that are not to do with the file846  // permissions (e.g. FILE_ATTRIBUTE_HIDDEN). We need to be careful to preserve847  // them.848  if (Permissions & all_write) {849    Attributes &= ~FILE_ATTRIBUTE_READONLY;850    if (Attributes == 0)851      // FILE_ATTRIBUTE_NORMAL indicates no other attributes are set.852      Attributes |= FILE_ATTRIBUTE_NORMAL;853  } else {854    Attributes |= FILE_ATTRIBUTE_READONLY;855    // FILE_ATTRIBUTE_NORMAL is not compatible with any other attributes, so856    // remove it, if it is present.857    Attributes &= ~FILE_ATTRIBUTE_NORMAL;858  }859 860  if (!::SetFileAttributesW(PathUTF16.begin(), Attributes))861    return mapWindowsError(GetLastError());862 863  return std::error_code();864}865 866std::error_code setPermissions(int FD, perms Permissions) {867  // FIXME Not implemented.868  return std::make_error_code(std::errc::not_supported);869}870 871std::error_code setLastAccessAndModificationTime(int FD, TimePoint<> AccessTime,872                                                 TimePoint<> ModificationTime) {873  FILETIME AccessFT = toFILETIME(AccessTime);874  FILETIME ModifyFT = toFILETIME(ModificationTime);875  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));876  if (!SetFileTime(FileHandle, NULL, &AccessFT, &ModifyFT))877    return mapWindowsError(::GetLastError());878  return std::error_code();879}880 881std::error_code mapped_file_region::init(sys::fs::file_t OrigFileHandle,882                                         uint64_t Offset, mapmode Mode) {883  this->Mode = Mode;884  if (OrigFileHandle == INVALID_HANDLE_VALUE)885    return make_error_code(errc::bad_file_descriptor);886 887  DWORD flprotect;888  switch (Mode) {889  case readonly:890    flprotect = PAGE_READONLY;891    break;892  case readwrite:893    flprotect = PAGE_READWRITE;894    break;895  case priv:896    flprotect = PAGE_WRITECOPY;897    break;898  }899 900  HANDLE FileMappingHandle = ::CreateFileMappingW(OrigFileHandle, 0, flprotect,901                                                  Hi_32(Size), Lo_32(Size), 0);902  if (FileMappingHandle == NULL) {903    std::error_code ec = mapWindowsError(GetLastError());904    return ec;905  }906 907  DWORD dwDesiredAccess;908  switch (Mode) {909  case readonly:910    dwDesiredAccess = FILE_MAP_READ;911    break;912  case readwrite:913    dwDesiredAccess = FILE_MAP_WRITE;914    break;915  case priv:916    dwDesiredAccess = FILE_MAP_COPY;917    break;918  }919  Mapping = ::MapViewOfFile(FileMappingHandle, dwDesiredAccess, Offset >> 32,920                            Offset & 0xffffffff, Size);921  if (Mapping == NULL) {922    std::error_code ec = mapWindowsError(GetLastError());923    ::CloseHandle(FileMappingHandle);924    return ec;925  }926 927  if (Size == 0) {928    MEMORY_BASIC_INFORMATION mbi;929    SIZE_T Result = VirtualQuery(Mapping, &mbi, sizeof(mbi));930    if (Result == 0) {931      std::error_code ec = mapWindowsError(GetLastError());932      ::UnmapViewOfFile(Mapping);933      ::CloseHandle(FileMappingHandle);934      return ec;935    }936    Size = mbi.RegionSize;937  }938 939  // Close the file mapping handle, as it's kept alive by the file mapping. But940  // neither the file mapping nor the file mapping handle keep the file handle941  // alive, so we need to keep a reference to the file in case all other handles942  // are closed and the file is deleted, which may cause invalid data to be read943  // from the file.944  ::CloseHandle(FileMappingHandle);945  if (!::DuplicateHandle(::GetCurrentProcess(), OrigFileHandle,946                         ::GetCurrentProcess(), &FileHandle, 0, 0,947                         DUPLICATE_SAME_ACCESS)) {948    std::error_code ec = mapWindowsError(GetLastError());949    ::UnmapViewOfFile(Mapping);950    return ec;951  }952 953  return std::error_code();954}955 956mapped_file_region::mapped_file_region(sys::fs::file_t fd, mapmode mode,957                                       size_t length, uint64_t offset,958                                       std::error_code &ec)959    : Size(length) {960  ec = init(fd, offset, mode);961  if (ec)962    copyFrom(mapped_file_region());963}964 965static bool hasFlushBufferKernelBug() {966  static bool Ret{GetWindowsOSVersion() < llvm::VersionTuple(10, 0, 0, 17763)};967  return Ret;968}969 970static bool isEXE(StringRef Magic) {971  static const char PEMagic[] = {'P', 'E', '\0', '\0'};972  if (Magic.starts_with(StringRef("MZ")) && Magic.size() >= 0x3c + 4) {973    uint32_t off = read32le(Magic.data() + 0x3c);974    // PE/COFF file, either EXE or DLL.975    if (Magic.substr(off).starts_with(StringRef(PEMagic, sizeof(PEMagic))))976      return true;977  }978  return false;979}980 981void mapped_file_region::unmapImpl() {982  if (Mapping) {983 984    bool Exe = isEXE(StringRef((char *)Mapping, Size));985 986    ::UnmapViewOfFile(Mapping);987 988    if (Mode == mapmode::readwrite) {989      bool DoFlush = Exe && hasFlushBufferKernelBug();990      // There is a Windows kernel bug, the exact trigger conditions of which991      // are not well understood.  When triggered, dirty pages are not properly992      // flushed and subsequent process's attempts to read a file can return993      // invalid data.  Calling FlushFileBuffers on the write handle is994      // sufficient to ensure that this bug is not triggered.995      // The bug only occurs when writing an executable and executing it right996      // after, under high I/O pressure.997      if (!DoFlush) {998        // Separately, on VirtualBox Shared Folder mounts, writes via memory999        // maps always end up unflushed (regardless of version of Windows),1000        // unless flushed with this explicit call, if they are renamed with1001        // SetFileInformationByHandle(FileRenameInfo) before closing the output1002        // handle.1003        //1004        // As the flushing is quite expensive, use a heuristic to limit the1005        // cases where we do the flushing. Only do the flushing if we aren't1006        // sure we are on a local file system.1007        bool IsLocal = false;1008        SmallVector<wchar_t, 128> FinalPath;1009        if (!realPathFromHandle(FileHandle, FinalPath)) {1010          // Not checking the return value here - if the check fails, assume the1011          // file isn't local.1012          is_local_internal(FinalPath, IsLocal);1013        }1014        DoFlush = !IsLocal;1015      }1016      if (DoFlush)1017        ::FlushFileBuffers(FileHandle);1018    }1019 1020    ::CloseHandle(FileHandle);1021  }1022}1023 1024void mapped_file_region::dontNeedImpl() {}1025 1026std::error_code mapped_file_region::sync() const {1027  if (!::FlushViewOfFile(Mapping, Size))1028    return mapWindowsError(GetLastError());1029  if (!::FlushFileBuffers(FileHandle))1030    return mapWindowsError(GetLastError());1031  return std::error_code();1032}1033 1034int mapped_file_region::alignment() {1035  SYSTEM_INFO SysInfo;1036  ::GetSystemInfo(&SysInfo);1037  return SysInfo.dwAllocationGranularity;1038}1039 1040static basic_file_status status_from_find_data(WIN32_FIND_DATAW *FindData) {1041  return basic_file_status(file_type_from_attrs(FindData->dwFileAttributes),1042                           perms_from_attrs(FindData->dwFileAttributes),1043                           FindData->ftLastAccessTime.dwHighDateTime,1044                           FindData->ftLastAccessTime.dwLowDateTime,1045                           FindData->ftLastWriteTime.dwHighDateTime,1046                           FindData->ftLastWriteTime.dwLowDateTime,1047                           FindData->nFileSizeHigh, FindData->nFileSizeLow);1048}1049 1050std::error_code detail::directory_iterator_construct(detail::DirIterState &IT,1051                                                     StringRef Path,1052                                                     bool FollowSymlinks) {1053  SmallVector<wchar_t, 128> PathUTF16;1054 1055  if (std::error_code EC = widenPath(Path, PathUTF16))1056    return EC;1057 1058  // Convert path to the format that Windows is happy with.1059  size_t PathUTF16Len = PathUTF16.size();1060  if (PathUTF16Len > 0 && !is_separator(PathUTF16[PathUTF16Len - 1]) &&1061      PathUTF16[PathUTF16Len - 1] != L':') {1062    PathUTF16.push_back(L'\\');1063    PathUTF16.push_back(L'*');1064  } else {1065    PathUTF16.push_back(L'*');1066  }1067 1068  //  Get the first directory entry.1069  WIN32_FIND_DATAW FirstFind;1070  ScopedFindHandle FindHandle(::FindFirstFileExW(1071      c_str(PathUTF16), FindExInfoBasic, &FirstFind, FindExSearchNameMatch,1072      NULL, FIND_FIRST_EX_LARGE_FETCH));1073  if (!FindHandle)1074    return mapWindowsError(::GetLastError());1075 1076  size_t FilenameLen = ::wcslen(FirstFind.cFileName);1077  while ((FilenameLen == 1 && FirstFind.cFileName[0] == L'.') ||1078         (FilenameLen == 2 && FirstFind.cFileName[0] == L'.' &&1079          FirstFind.cFileName[1] == L'.'))1080    if (!::FindNextFileW(FindHandle, &FirstFind)) {1081      DWORD LastError = ::GetLastError();1082      // Check for end.1083      if (LastError == ERROR_NO_MORE_FILES)1084        return detail::directory_iterator_destruct(IT);1085      return mapWindowsError(LastError);1086    } else {1087      FilenameLen = ::wcslen(FirstFind.cFileName);1088    }1089 1090  // Construct the current directory entry.1091  SmallString<128> DirectoryEntryNameUTF8;1092  if (std::error_code EC =1093          UTF16ToUTF8(FirstFind.cFileName, ::wcslen(FirstFind.cFileName),1094                      DirectoryEntryNameUTF8))1095    return EC;1096 1097  IT.IterationHandle = intptr_t(FindHandle.take());1098  SmallString<128> DirectoryEntryPath(Path);1099  path::append(DirectoryEntryPath, DirectoryEntryNameUTF8);1100  IT.CurrentEntry =1101      directory_entry(DirectoryEntryPath, FollowSymlinks,1102                      file_type_from_attrs(FirstFind.dwFileAttributes),1103                      status_from_find_data(&FirstFind));1104 1105  return std::error_code();1106}1107 1108std::error_code detail::directory_iterator_destruct(detail::DirIterState &IT) {1109  if (IT.IterationHandle != 0)1110    // Closes the handle if it's valid.1111    ScopedFindHandle close(HANDLE(IT.IterationHandle));1112  IT.IterationHandle = 0;1113  IT.CurrentEntry = directory_entry();1114  return std::error_code();1115}1116 1117std::error_code detail::directory_iterator_increment(detail::DirIterState &IT) {1118  WIN32_FIND_DATAW FindData;1119  if (!::FindNextFileW(HANDLE(IT.IterationHandle), &FindData)) {1120    DWORD LastError = ::GetLastError();1121    // Check for end.1122    if (LastError == ERROR_NO_MORE_FILES)1123      return detail::directory_iterator_destruct(IT);1124    return mapWindowsError(LastError);1125  }1126 1127  size_t FilenameLen = ::wcslen(FindData.cFileName);1128  if ((FilenameLen == 1 && FindData.cFileName[0] == L'.') ||1129      (FilenameLen == 2 && FindData.cFileName[0] == L'.' &&1130       FindData.cFileName[1] == L'.'))1131    return directory_iterator_increment(IT);1132 1133  SmallString<128> DirectoryEntryPathUTF8;1134  if (std::error_code EC =1135          UTF16ToUTF8(FindData.cFileName, ::wcslen(FindData.cFileName),1136                      DirectoryEntryPathUTF8))1137    return EC;1138 1139  IT.CurrentEntry.replace_filename(1140      Twine(DirectoryEntryPathUTF8),1141      file_type_from_attrs(FindData.dwFileAttributes),1142      status_from_find_data(&FindData));1143  return std::error_code();1144}1145 1146ErrorOr<basic_file_status> directory_entry::status() const { return Status; }1147 1148static std::error_code nativeFileToFd(Expected<HANDLE> H, int &ResultFD,1149                                      OpenFlags Flags) {1150  int CrtOpenFlags = 0;1151  if (Flags & OF_Append)1152    CrtOpenFlags |= _O_APPEND;1153 1154  if (Flags & OF_CRLF) {1155    assert(Flags & OF_Text && "Flags set OF_CRLF without OF_Text");1156    CrtOpenFlags |= _O_TEXT;1157  }1158 1159  ResultFD = -1;1160  if (!H)1161    return errorToErrorCode(H.takeError());1162 1163  ResultFD = ::_open_osfhandle(intptr_t(*H), CrtOpenFlags);1164  if (ResultFD == -1) {1165    ::CloseHandle(*H);1166    return mapWindowsError(ERROR_INVALID_HANDLE);1167  }1168  return std::error_code();1169}1170 1171static DWORD nativeDisposition(CreationDisposition Disp, OpenFlags Flags) {1172  // This is a compatibility hack.  Really we should respect the creation1173  // disposition, but a lot of old code relied on the implicit assumption that1174  // OF_Append implied it would open an existing file.  Since the disposition is1175  // now explicit and defaults to CD_CreateAlways, this assumption would cause1176  // any usage of OF_Append to append to a new file, even if the file already1177  // existed.  A better solution might have two new creation dispositions:1178  // CD_AppendAlways and CD_AppendNew.  This would also address the problem of1179  // OF_Append being used on a read-only descriptor, which doesn't make sense.1180  if (Flags & OF_Append)1181    return OPEN_ALWAYS;1182 1183  switch (Disp) {1184  case CD_CreateAlways:1185    return CREATE_ALWAYS;1186  case CD_CreateNew:1187    return CREATE_NEW;1188  case CD_OpenAlways:1189    return OPEN_ALWAYS;1190  case CD_OpenExisting:1191    return OPEN_EXISTING;1192  }1193  llvm_unreachable("unreachable!");1194}1195 1196static DWORD nativeAccess(FileAccess Access, OpenFlags Flags) {1197  DWORD Result = 0;1198  if (Access & FA_Read)1199    Result |= GENERIC_READ;1200  if (Access & FA_Write)1201    Result |= GENERIC_WRITE;1202  if (Flags & OF_Delete)1203    Result |= DELETE;1204  if (Flags & OF_UpdateAtime)1205    Result |= FILE_WRITE_ATTRIBUTES;1206  return Result;1207}1208 1209static std::error_code openNativeFileInternal(const Twine &Name,1210                                              file_t &ResultFile, DWORD Disp,1211                                              DWORD Access, DWORD Flags,1212                                              bool Inherit = false) {1213  SmallVector<wchar_t, 128> PathUTF16;1214  if (std::error_code EC = widenPath(Name, PathUTF16))1215    return EC;1216 1217  SECURITY_ATTRIBUTES SA;1218  SA.nLength = sizeof(SA);1219  SA.lpSecurityDescriptor = nullptr;1220  SA.bInheritHandle = Inherit;1221 1222  HANDLE H =1223      ::CreateFileW(PathUTF16.begin(), Access,1224                    FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, &SA,1225                    Disp, Flags, NULL);1226  if (H == INVALID_HANDLE_VALUE) {1227    DWORD LastError = ::GetLastError();1228    std::error_code EC = mapWindowsError(LastError);1229    // Provide a better error message when trying to open directories.1230    // This only runs if we failed to open the file, so there is probably1231    // no performances issues.1232    if (LastError != ERROR_ACCESS_DENIED)1233      return EC;1234    if (is_directory(Name))1235      return make_error_code(errc::is_a_directory);1236    return EC;1237  }1238  ResultFile = H;1239  return std::error_code();1240}1241 1242Expected<file_t> openNativeFile(const Twine &Name, CreationDisposition Disp,1243                                FileAccess Access, OpenFlags Flags,1244                                unsigned Mode) {1245  // Verify that we don't have both "append" and "excl".1246  assert((!(Disp == CD_CreateNew) || !(Flags & OF_Append)) &&1247         "Cannot specify both 'CreateNew' and 'Append' file creation flags!");1248 1249  DWORD NativeDisp = nativeDisposition(Disp, Flags);1250  DWORD NativeAccess = nativeAccess(Access, Flags);1251 1252  bool Inherit = false;1253  if (Flags & OF_ChildInherit)1254    Inherit = true;1255 1256  file_t Result;1257  std::error_code EC = openNativeFileInternal(1258      Name, Result, NativeDisp, NativeAccess, FILE_ATTRIBUTE_NORMAL, Inherit);1259  if (EC)1260    return errorCodeToError(EC);1261 1262  if (Flags & OF_UpdateAtime) {1263    FILETIME FileTime;1264    SYSTEMTIME SystemTime;1265    GetSystemTime(&SystemTime);1266    if (SystemTimeToFileTime(&SystemTime, &FileTime) == 0 ||1267        SetFileTime(Result, NULL, &FileTime, NULL) == 0) {1268      DWORD LastError = ::GetLastError();1269      ::CloseHandle(Result);1270      return errorCodeToError(mapWindowsError(LastError));1271    }1272  }1273 1274  return Result;1275}1276 1277std::error_code openFile(const Twine &Name, int &ResultFD,1278                         CreationDisposition Disp, FileAccess Access,1279                         OpenFlags Flags, unsigned int Mode) {1280  Expected<file_t> Result = openNativeFile(Name, Disp, Access, Flags);1281  if (!Result)1282    return errorToErrorCode(Result.takeError());1283 1284  return nativeFileToFd(*Result, ResultFD, Flags);1285}1286 1287static std::error_code directoryRealPath(const Twine &Name,1288                                         SmallVectorImpl<char> &RealPath) {1289  file_t File;1290  std::error_code EC = openNativeFileInternal(1291      Name, File, OPEN_EXISTING, GENERIC_READ, FILE_FLAG_BACKUP_SEMANTICS);1292  if (EC)1293    return EC;1294 1295  EC = realPathFromHandle(File, RealPath);1296  ::CloseHandle(File);1297  return EC;1298}1299 1300std::error_code openFileForRead(const Twine &Name, int &ResultFD,1301                                OpenFlags Flags,1302                                SmallVectorImpl<char> *RealPath) {1303  Expected<HANDLE> NativeFile = openNativeFileForRead(Name, Flags, RealPath);1304  return nativeFileToFd(std::move(NativeFile), ResultFD, OF_None);1305}1306 1307Expected<file_t> openNativeFileForRead(const Twine &Name, OpenFlags Flags,1308                                       SmallVectorImpl<char> *RealPath) {1309  Expected<file_t> Result =1310      openNativeFile(Name, CD_OpenExisting, FA_Read, Flags);1311 1312  // Fetch the real name of the file, if the user asked1313  if (Result && RealPath)1314    realPathFromHandle(*Result, *RealPath);1315 1316  return Result;1317}1318 1319file_t convertFDToNativeFile(int FD) {1320  return reinterpret_cast<HANDLE>(::_get_osfhandle(FD));1321}1322 1323file_t getStdinHandle() { return ::GetStdHandle(STD_INPUT_HANDLE); }1324file_t getStdoutHandle() { return ::GetStdHandle(STD_OUTPUT_HANDLE); }1325file_t getStderrHandle() { return ::GetStdHandle(STD_ERROR_HANDLE); }1326 1327Expected<size_t> readNativeFileImpl(file_t FileHandle,1328                                    MutableArrayRef<char> Buf,1329                                    OVERLAPPED *Overlap) {1330  // ReadFile can only read 2GB at a time. The caller should check the number of1331  // bytes and read in a loop until termination.1332  DWORD BytesToRead =1333      std::min(size_t(std::numeric_limits<DWORD>::max()), Buf.size());1334  DWORD BytesRead = 0;1335  if (::ReadFile(FileHandle, Buf.data(), BytesToRead, &BytesRead, Overlap))1336    return BytesRead;1337  DWORD Err = ::GetLastError();1338  // EOF is not an error.1339  if (Err == ERROR_BROKEN_PIPE || Err == ERROR_HANDLE_EOF)1340    return BytesRead;1341  return errorCodeToError(mapWindowsError(Err));1342}1343 1344Expected<size_t> readNativeFile(file_t FileHandle, MutableArrayRef<char> Buf) {1345  return readNativeFileImpl(FileHandle, Buf, /*Overlap=*/nullptr);1346}1347 1348Expected<size_t> readNativeFileSlice(file_t FileHandle,1349                                     MutableArrayRef<char> Buf,1350                                     uint64_t Offset) {1351  OVERLAPPED Overlapped = {};1352  Overlapped.Offset = uint32_t(Offset);1353  Overlapped.OffsetHigh = uint32_t(Offset >> 32);1354  return readNativeFileImpl(FileHandle, Buf, &Overlapped);1355}1356 1357std::error_code tryLockFile(int FD, std::chrono::milliseconds Timeout,1358                            LockKind Kind) {1359  DWORD Flags = Kind == LockKind::Exclusive ? LOCKFILE_EXCLUSIVE_LOCK : 0;1360  Flags |= LOCKFILE_FAIL_IMMEDIATELY;1361  OVERLAPPED OV = {};1362  file_t File = convertFDToNativeFile(FD);1363  auto Start = std::chrono::steady_clock::now();1364  auto End = Start + Timeout;1365  do {1366    if (::LockFileEx(File, Flags, 0, MAXDWORD, MAXDWORD, &OV))1367      return std::error_code();1368    DWORD Error = ::GetLastError();1369    if (Error == ERROR_LOCK_VIOLATION) {1370      if (Timeout.count() == 0)1371        break;1372      ::Sleep(1);1373      continue;1374    }1375    return mapWindowsError(Error);1376  } while (std::chrono::steady_clock::now() < End);1377  return mapWindowsError(ERROR_LOCK_VIOLATION);1378}1379 1380std::error_code lockFile(int FD, LockKind Kind) {1381  DWORD Flags = Kind == LockKind::Exclusive ? LOCKFILE_EXCLUSIVE_LOCK : 0;1382  OVERLAPPED OV = {};1383  file_t File = convertFDToNativeFile(FD);1384  if (::LockFileEx(File, Flags, 0, MAXDWORD, MAXDWORD, &OV))1385    return std::error_code();1386  DWORD Error = ::GetLastError();1387  return mapWindowsError(Error);1388}1389 1390std::error_code unlockFile(int FD) {1391  OVERLAPPED OV = {};1392  file_t File = convertFDToNativeFile(FD);1393  if (::UnlockFileEx(File, 0, MAXDWORD, MAXDWORD, &OV))1394    return std::error_code();1395  return mapWindowsError(::GetLastError());1396}1397 1398std::error_code closeFile(file_t &F) {1399  file_t TmpF = F;1400  F = kInvalidFile;1401  if (!::CloseHandle(TmpF))1402    return mapWindowsError(::GetLastError());1403  return std::error_code();1404}1405 1406std::error_code remove_directories(const Twine &path, bool IgnoreErrors) {1407  SmallString<128> NativePath;1408  llvm::sys::path::native(path, NativePath, path::Style::windows_backslash);1409  // Convert to utf-16.1410  SmallVector<wchar_t, 128> Path16;1411  std::error_code EC = widenPath(NativePath, Path16);1412  if (EC && !IgnoreErrors)1413    return EC;1414 1415  // SHFileOperation() accepts a list of paths, and so must be double null-1416  // terminated to indicate the end of the list.  The buffer is already null1417  // terminated, but since that null character is not considered part of the1418  // vector's size, pushing another one will just consume that byte.  So we1419  // need to push 2 null terminators.1420  Path16.push_back(0);1421  Path16.push_back(0);1422 1423  HRESULT HR;1424  do {1425    HR =1426        CoInitializeEx(NULL, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE);1427    if (FAILED(HR))1428      break;1429    auto Uninitialize = make_scope_exit([] { CoUninitialize(); });1430    IFileOperation *FileOp = NULL;1431    HR = CoCreateInstance(CLSID_FileOperation, NULL, CLSCTX_ALL,1432                          IID_PPV_ARGS(&FileOp));1433    if (FAILED(HR))1434      break;1435    auto FileOpRelease = make_scope_exit([&FileOp] { FileOp->Release(); });1436    HR = FileOp->SetOperationFlags(FOF_NO_UI | FOFX_NOCOPYHOOKS);1437    if (FAILED(HR))1438      break;1439    PIDLIST_ABSOLUTE PIDL = ILCreateFromPathW(Path16.data());1440    auto FreePIDL = make_scope_exit([&PIDL] { ILFree(PIDL); });1441    IShellItem *ShItem = NULL;1442    HR = SHCreateItemFromIDList(PIDL, IID_PPV_ARGS(&ShItem));1443    if (FAILED(HR))1444      break;1445    auto ShItemRelease = make_scope_exit([&ShItem] { ShItem->Release(); });1446    HR = FileOp->DeleteItem(ShItem, NULL);1447    if (FAILED(HR))1448      break;1449    HR = FileOp->PerformOperations();1450  } while (false);1451  if (FAILED(HR) && !IgnoreErrors)1452    return mapWindowsError(HRESULT_CODE(HR));1453  return std::error_code();1454}1455 1456static void expandTildeExpr(SmallVectorImpl<char> &Path) {1457  // Path does not begin with a tilde expression.1458  if (Path.empty() || Path[0] != '~')1459    return;1460 1461  StringRef PathStr(Path.begin(), Path.size());1462  PathStr = PathStr.drop_front();1463  StringRef Expr =1464      PathStr.take_until([](char c) { return path::is_separator(c); });1465 1466  if (!Expr.empty()) {1467    // This is probably a ~username/ expression.  Don't support this on Windows.1468    return;1469  }1470 1471  SmallString<128> HomeDir;1472  if (!path::home_directory(HomeDir)) {1473    // For some reason we couldn't get the home directory.  Just exit.1474    return;1475  }1476 1477  // Overwrite the first character and insert the rest.1478  Path[0] = HomeDir[0];1479  Path.insert(Path.begin() + 1, HomeDir.begin() + 1, HomeDir.end());1480}1481 1482void expand_tilde(const Twine &path, SmallVectorImpl<char> &dest) {1483  dest.clear();1484  if (path.isTriviallyEmpty())1485    return;1486 1487  path.toVector(dest);1488  expandTildeExpr(dest);1489 1490  return;1491}1492 1493std::error_code real_path(const Twine &path, SmallVectorImpl<char> &dest,1494                          bool expand_tilde) {1495  dest.clear();1496  if (path.isTriviallyEmpty())1497    return std::error_code();1498 1499  if (expand_tilde) {1500    SmallString<128> Storage;1501    path.toVector(Storage);1502    expandTildeExpr(Storage);1503    return real_path(Storage, dest, false);1504  }1505 1506  if (is_directory(path))1507    return directoryRealPath(path, dest);1508 1509  int fd;1510  if (std::error_code EC =1511          llvm::sys::fs::openFileForRead(path, fd, OF_None, &dest))1512    return EC;1513  ::close(fd);1514  return std::error_code();1515}1516 1517} // end namespace fs1518 1519namespace path {1520static bool getKnownFolderPath(KNOWNFOLDERID folderId,1521                               SmallVectorImpl<char> &result) {1522  wchar_t *path = nullptr;1523  if (::SHGetKnownFolderPath(folderId, KF_FLAG_CREATE, nullptr, &path) != S_OK)1524    return false;1525 1526  bool ok = !UTF16ToUTF8(path, ::wcslen(path), result);1527  ::CoTaskMemFree(path);1528  if (ok)1529    llvm::sys::path::make_preferred(result);1530  return ok;1531}1532 1533bool home_directory(SmallVectorImpl<char> &result) {1534  return getKnownFolderPath(FOLDERID_Profile, result);1535}1536 1537bool user_config_directory(SmallVectorImpl<char> &result) {1538  // Either local or roaming appdata may be suitable in some cases, depending1539  // on the data. Local is more conservative, Roaming may not always be correct.1540  return getKnownFolderPath(FOLDERID_LocalAppData, result);1541}1542 1543bool cache_directory(SmallVectorImpl<char> &result) {1544  return getKnownFolderPath(FOLDERID_LocalAppData, result);1545}1546 1547static bool getTempDirEnvVar(const wchar_t *Var, SmallVectorImpl<char> &Res) {1548  SmallVector<wchar_t, 1024> Buf;1549  size_t Size = 1024;1550  do {1551    Buf.resize_for_overwrite(Size);1552    Size = GetEnvironmentVariableW(Var, Buf.data(), Buf.size());1553    if (Size == 0)1554      return false;1555 1556    // Try again with larger buffer.1557  } while (Size > Buf.size());1558  Buf.truncate(Size);1559 1560  return !windows::UTF16ToUTF8(Buf.data(), Size, Res);1561}1562 1563static bool getTempDirEnvVar(SmallVectorImpl<char> &Res) {1564  const wchar_t *EnvironmentVariables[] = {L"TMP", L"TEMP", L"USERPROFILE"};1565  for (auto *Env : EnvironmentVariables) {1566    if (getTempDirEnvVar(Env, Res))1567      return true;1568  }1569  return false;1570}1571 1572void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {1573  (void)ErasedOnReboot;1574  Result.clear();1575 1576  // Check whether the temporary directory is specified by an environment var.1577  // This matches GetTempPath logic to some degree. GetTempPath is not used1578  // directly as it cannot handle evn var longer than 130 chars on Windows 71579  // (fixed on Windows 8).1580  if (getTempDirEnvVar(Result)) {1581    assert(!Result.empty() && "Unexpected empty path");1582    native(Result); // Some Unix-like shells use Unix path separator in $TMP.1583    fs::make_absolute(Result); // Make it absolute if not already.1584    return;1585  }1586 1587  // Fall back to a system default.1588  const char *DefaultResult = "C:\\Temp";1589  Result.append(DefaultResult, DefaultResult + strlen(DefaultResult));1590  llvm::sys::path::make_preferred(Result);1591}1592} // end namespace path1593 1594namespace windows {1595std::error_code CodePageToUTF16(unsigned codepage, llvm::StringRef original,1596                                llvm::SmallVectorImpl<wchar_t> &utf16) {1597  if (!original.empty()) {1598    int len =1599        ::MultiByteToWideChar(codepage, MB_ERR_INVALID_CHARS, original.begin(),1600                              original.size(), utf16.begin(), 0);1601 1602    if (len == 0) {1603      return mapWindowsError(::GetLastError());1604    }1605 1606    utf16.reserve(len + 1);1607    utf16.resize_for_overwrite(len);1608 1609    len =1610        ::MultiByteToWideChar(codepage, MB_ERR_INVALID_CHARS, original.begin(),1611                              original.size(), utf16.begin(), utf16.size());1612 1613    if (len == 0) {1614      return mapWindowsError(::GetLastError());1615    }1616  }1617 1618  // Make utf16 null terminated.1619  utf16.push_back(0);1620  utf16.pop_back();1621 1622  return std::error_code();1623}1624 1625std::error_code UTF8ToUTF16(llvm::StringRef utf8,1626                            llvm::SmallVectorImpl<wchar_t> &utf16) {1627  return CodePageToUTF16(CP_UTF8, utf8, utf16);1628}1629 1630std::error_code CurCPToUTF16(llvm::StringRef curcp,1631                             llvm::SmallVectorImpl<wchar_t> &utf16) {1632  return CodePageToUTF16(CP_ACP, curcp, utf16);1633}1634 1635static std::error_code UTF16ToCodePage(unsigned codepage, const wchar_t *utf16,1636                                       size_t utf16_len,1637                                       llvm::SmallVectorImpl<char> &converted) {1638  if (utf16_len) {1639    // Get length.1640    int len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len,1641                                    converted.begin(), 0, NULL, NULL);1642 1643    if (len == 0) {1644      return mapWindowsError(::GetLastError());1645    }1646 1647    converted.reserve(len + 1);1648    converted.resize_for_overwrite(len);1649 1650    // Now do the actual conversion.1651    len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, converted.data(),1652                                converted.size(), NULL, NULL);1653 1654    if (len == 0) {1655      return mapWindowsError(::GetLastError());1656    }1657  }1658 1659  // Make the new string null terminated.1660  converted.push_back(0);1661  converted.pop_back();1662 1663  return std::error_code();1664}1665 1666std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,1667                            llvm::SmallVectorImpl<char> &utf8) {1668  return UTF16ToCodePage(CP_UTF8, utf16, utf16_len, utf8);1669}1670 1671std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len,1672                             llvm::SmallVectorImpl<char> &curcp) {1673  return UTF16ToCodePage(CP_ACP, utf16, utf16_len, curcp);1674}1675 1676} // end namespace windows1677} // end namespace sys1678} // end namespace llvm1679