1//===- llvm/Support/Windows/Path.inc - Windows Path Impl --------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the Windows specific implementation of the Path API.
11//
12//===----------------------------------------------------------------------===//
13
14//===----------------------------------------------------------------------===//
15//=== WARNING: Implementation here must contain only generic Windows code that
16//===          is guaranteed to work on *all* Windows variants.
17//===----------------------------------------------------------------------===//
18
19#include "llvm/ADT/STLExtras.h"
20#include "llvm/Support/WindowsError.h"
21#include <fcntl.h>
22#include <io.h>
23#include <sys/stat.h>
24#include <sys/types.h>
25
26// These two headers must be included last, and make sure shlobj is required
27// after Windows.h to make sure it picks up our definition of _WIN32_WINNT
28#include "WindowsSupport.h"
29#include <shlobj.h>
30
31#undef max
32
33// MinGW doesn't define this.
34#ifndef _ERRNO_T_DEFINED
35#define _ERRNO_T_DEFINED
36typedef int errno_t;
37#endif
38
39#ifdef _MSC_VER
40# pragma comment(lib, "advapi32.lib")  // This provides CryptAcquireContextW.
41# pragma comment(lib, "ole32.lib")     // This provides CoTaskMemFree
42#endif
43
44using namespace llvm;
45
46using llvm::sys::windows::UTF8ToUTF16;
47using llvm::sys::windows::UTF16ToUTF8;
48using llvm::sys::path::widenPath;
49
50static bool is_separator(const wchar_t value) {
51  switch (value) {
52  case L'\\':
53  case L'/':
54    return true;
55  default:
56    return false;
57  }
58}
59
60namespace llvm {
61namespace sys  {
62namespace path {
63
64// Convert a UTF-8 path to UTF-16.  Also, if the absolute equivalent of the
65// path is longer than CreateDirectory can tolerate, make it absolute and
66// prefixed by '\\?\'.
67std::error_code widenPath(const Twine &Path8,
68                          SmallVectorImpl<wchar_t> &Path16) {
69  const size_t MaxDirLen = MAX_PATH - 12; // Must leave room for 8.3 filename.
70
71  // Several operations would convert Path8 to SmallString; more efficient to
72  // do it once up front.
73  SmallString<128> Path8Str;
74  Path8.toVector(Path8Str);
75
76  // If we made this path absolute, how much longer would it get?
77  size_t CurPathLen;
78  if (llvm::sys::path::is_absolute(Twine(Path8Str)))
79    CurPathLen = 0; // No contribution from current_path needed.
80  else {
81    CurPathLen = ::GetCurrentDirectoryW(0, NULL);
82    if (CurPathLen == 0)
83      return mapWindowsError(::GetLastError());
84  }
85
86  // Would the absolute path be longer than our limit?
87  if ((Path8Str.size() + CurPathLen) >= MaxDirLen &&
88      !Path8Str.startswith("\\\\?\\")) {
89    SmallString<2*MAX_PATH> FullPath("\\\\?\\");
90    if (CurPathLen) {
91      SmallString<80> CurPath;
92      if (std::error_code EC = llvm::sys::fs::current_path(CurPath))
93        return EC;
94      FullPath.append(CurPath);
95    }
96    // Traverse the requested path, canonicalizing . and .. as we go (because
97    // the \\?\ prefix is documented to treat them as real components).
98    // The iterators don't report separators and append() always attaches
99    // preferred_separator so we don't need to call native() on the result.
100    for (llvm::sys::path::const_iterator I = llvm::sys::path::begin(Path8Str),
101                                         E = llvm::sys::path::end(Path8Str);
102                                         I != E; ++I) {
103      if (I->size() == 1 && *I == ".")
104        continue;
105      if (I->size() == 2 && *I == "..")
106        llvm::sys::path::remove_filename(FullPath);
107      else
108        llvm::sys::path::append(FullPath, *I);
109    }
110    return UTF8ToUTF16(FullPath, Path16);
111  }
112
113  // Just use the caller's original path.
114  return UTF8ToUTF16(Path8Str, Path16);
115}
116} // end namespace path
117
118namespace fs {
119
120std::string getMainExecutable(const char *argv0, void *MainExecAddr) {
121  SmallVector<wchar_t, MAX_PATH> PathName;
122  DWORD Size = ::GetModuleFileNameW(NULL, PathName.data(), PathName.capacity());
123
124  // A zero return value indicates a failure other than insufficient space.
125  if (Size == 0)
126    return "";
127
128  // Insufficient space is determined by a return value equal to the size of
129  // the buffer passed in.
130  if (Size == PathName.capacity())
131    return "";
132
133  // On success, GetModuleFileNameW returns the number of characters written to
134  // the buffer not including the NULL terminator.
135  PathName.set_size(Size);
136
137  // Convert the result from UTF-16 to UTF-8.
138  SmallVector<char, MAX_PATH> PathNameUTF8;
139  if (UTF16ToUTF8(PathName.data(), PathName.size(), PathNameUTF8))
140    return "";
141
142  return std::string(PathNameUTF8.data());
143}
144
145UniqueID file_status::getUniqueID() const {
146  // The file is uniquely identified by the volume serial number along
147  // with the 64-bit file identifier.
148  uint64_t FileID = (static_cast<uint64_t>(FileIndexHigh) << 32ULL) |
149                    static_cast<uint64_t>(FileIndexLow);
150
151  return UniqueID(VolumeSerialNumber, FileID);
152}
153
154ErrorOr<space_info> disk_space(const Twine &Path) {
155  ULARGE_INTEGER Avail, Total, Free;
156  if (!::GetDiskFreeSpaceExA(Path.str().c_str(), &Avail, &Total, &Free))
157    return mapWindowsError(::GetLastError());
158  space_info SpaceInfo;
159  SpaceInfo.capacity =
160      (static_cast<uint64_t>(Total.HighPart) << 32) + Total.LowPart;
161  SpaceInfo.free = (static_cast<uint64_t>(Free.HighPart) << 32) + Free.LowPart;
162  SpaceInfo.available =
163      (static_cast<uint64_t>(Avail.HighPart) << 32) + Avail.LowPart;
164  return SpaceInfo;
165}
166
167TimePoint<> file_status::getLastAccessedTime() const {
168  FILETIME Time;
169  Time.dwLowDateTime = LastAccessedTimeLow;
170  Time.dwHighDateTime = LastAccessedTimeHigh;
171  return toTimePoint(Time);
172}
173
174TimePoint<> file_status::getLastModificationTime() const {
175  FILETIME Time;
176  Time.dwLowDateTime = LastWriteTimeLow;
177  Time.dwHighDateTime = LastWriteTimeHigh;
178  return toTimePoint(Time);
179}
180
181std::error_code current_path(SmallVectorImpl<char> &result) {
182  SmallVector<wchar_t, MAX_PATH> cur_path;
183  DWORD len = MAX_PATH;
184
185  do {
186    cur_path.reserve(len);
187    len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
188
189    // A zero return value indicates a failure other than insufficient space.
190    if (len == 0)
191      return mapWindowsError(::GetLastError());
192
193    // If there's insufficient space, the len returned is larger than the len
194    // given.
195  } while (len > cur_path.capacity());
196
197  // On success, GetCurrentDirectoryW returns the number of characters not
198  // including the null-terminator.
199  cur_path.set_size(len);
200  return UTF16ToUTF8(cur_path.begin(), cur_path.size(), result);
201}
202
203std::error_code create_directory(const Twine &path, bool IgnoreExisting,
204                                 perms Perms) {
205  SmallVector<wchar_t, 128> path_utf16;
206
207  if (std::error_code ec = widenPath(path, path_utf16))
208    return ec;
209
210  if (!::CreateDirectoryW(path_utf16.begin(), NULL)) {
211    DWORD LastError = ::GetLastError();
212    if (LastError != ERROR_ALREADY_EXISTS || !IgnoreExisting)
213      return mapWindowsError(LastError);
214  }
215
216  return std::error_code();
217}
218
219// We can't use symbolic links for windows.
220std::error_code create_link(const Twine &to, const Twine &from) {
221  // Convert to utf-16.
222  SmallVector<wchar_t, 128> wide_from;
223  SmallVector<wchar_t, 128> wide_to;
224  if (std::error_code ec = widenPath(from, wide_from))
225    return ec;
226  if (std::error_code ec = widenPath(to, wide_to))
227    return ec;
228
229  if (!::CreateHardLinkW(wide_from.begin(), wide_to.begin(), NULL))
230    return mapWindowsError(::GetLastError());
231
232  return std::error_code();
233}
234
235std::error_code create_hard_link(const Twine &to, const Twine &from) {
236	return create_link(to, from);
237}
238
239std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
240  SmallVector<wchar_t, 128> path_utf16;
241
242  file_status ST;
243  if (std::error_code EC = status(path, ST)) {
244    if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
245      return EC;
246    return std::error_code();
247  }
248
249  if (std::error_code ec = widenPath(path, path_utf16))
250    return ec;
251
252  if (ST.type() == file_type::directory_file) {
253    if (!::RemoveDirectoryW(c_str(path_utf16))) {
254      std::error_code EC = mapWindowsError(::GetLastError());
255      if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
256        return EC;
257    }
258    return std::error_code();
259  }
260  if (!::DeleteFileW(c_str(path_utf16))) {
261    std::error_code EC = mapWindowsError(::GetLastError());
262    if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
263      return EC;
264  }
265  return std::error_code();
266}
267
268std::error_code rename(const Twine &from, const Twine &to) {
269  // Convert to utf-16.
270  SmallVector<wchar_t, 128> wide_from;
271  SmallVector<wchar_t, 128> wide_to;
272  if (std::error_code ec = widenPath(from, wide_from))
273    return ec;
274  if (std::error_code ec = widenPath(to, wide_to))
275    return ec;
276
277  std::error_code ec = std::error_code();
278
279  // Retry while we see recoverable errors.
280  // System scanners (eg. indexer) might open the source file when it is written
281  // and closed.
282
283  bool TryReplace = true;
284
285  for (int i = 0; i < 2000; i++) {
286    if (i > 0)
287      ::Sleep(1);
288
289    if (TryReplace) {
290      // Try ReplaceFile first, as it is able to associate a new data stream
291      // with the destination even if the destination file is currently open.
292      if (::ReplaceFileW(wide_to.data(), wide_from.data(), NULL, 0, NULL, NULL))
293        return std::error_code();
294
295      DWORD ReplaceError = ::GetLastError();
296      ec = mapWindowsError(ReplaceError);
297
298      // If ReplaceFileW returned ERROR_UNABLE_TO_MOVE_REPLACEMENT or
299      // ERROR_UNABLE_TO_MOVE_REPLACEMENT_2, retry but only use MoveFileExW().
300      if (ReplaceError == ERROR_UNABLE_TO_MOVE_REPLACEMENT ||
301          ReplaceError == ERROR_UNABLE_TO_MOVE_REPLACEMENT_2) {
302        TryReplace = false;
303        continue;
304      }
305      // If ReplaceFileW returned ERROR_UNABLE_TO_REMOVE_REPLACED, retry
306      // using ReplaceFileW().
307      if (ReplaceError == ERROR_UNABLE_TO_REMOVE_REPLACED)
308        continue;
309      // We get ERROR_FILE_NOT_FOUND if the destination file is missing.
310      // MoveFileEx can handle this case.
311      if (ReplaceError != ERROR_ACCESS_DENIED &&
312          ReplaceError != ERROR_FILE_NOT_FOUND &&
313          ReplaceError != ERROR_SHARING_VIOLATION)
314        break;
315    }
316
317    if (::MoveFileExW(wide_from.begin(), wide_to.begin(),
318                      MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING))
319      return std::error_code();
320
321    DWORD MoveError = ::GetLastError();
322    ec = mapWindowsError(MoveError);
323    if (MoveError != ERROR_ACCESS_DENIED) break;
324  }
325
326  return ec;
327}
328
329std::error_code resize_file(int FD, uint64_t Size) {
330#ifdef HAVE__CHSIZE_S
331  errno_t error = ::_chsize_s(FD, Size);
332#else
333  errno_t error = ::_chsize(FD, Size);
334#endif
335  return std::error_code(error, std::generic_category());
336}
337
338std::error_code access(const Twine &Path, AccessMode Mode) {
339  SmallVector<wchar_t, 128> PathUtf16;
340
341  if (std::error_code EC = widenPath(Path, PathUtf16))
342    return EC;
343
344  DWORD Attributes = ::GetFileAttributesW(PathUtf16.begin());
345
346  if (Attributes == INVALID_FILE_ATTRIBUTES) {
347    // See if the file didn't actually exist.
348    DWORD LastError = ::GetLastError();
349    if (LastError != ERROR_FILE_NOT_FOUND &&
350        LastError != ERROR_PATH_NOT_FOUND)
351      return mapWindowsError(LastError);
352    return errc::no_such_file_or_directory;
353  }
354
355  if (Mode == AccessMode::Write && (Attributes & FILE_ATTRIBUTE_READONLY))
356    return errc::permission_denied;
357
358  return std::error_code();
359}
360
361bool can_execute(const Twine &Path) {
362  return !access(Path, AccessMode::Execute) ||
363         !access(Path + ".exe", AccessMode::Execute);
364}
365
366bool equivalent(file_status A, file_status B) {
367  assert(status_known(A) && status_known(B));
368  return A.FileIndexHigh         == B.FileIndexHigh &&
369         A.FileIndexLow          == B.FileIndexLow &&
370         A.FileSizeHigh          == B.FileSizeHigh &&
371         A.FileSizeLow           == B.FileSizeLow &&
372         A.LastAccessedTimeHigh  == B.LastAccessedTimeHigh &&
373         A.LastAccessedTimeLow   == B.LastAccessedTimeLow &&
374         A.LastWriteTimeHigh     == B.LastWriteTimeHigh &&
375         A.LastWriteTimeLow      == B.LastWriteTimeLow &&
376         A.VolumeSerialNumber    == B.VolumeSerialNumber;
377}
378
379std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
380  file_status fsA, fsB;
381  if (std::error_code ec = status(A, fsA))
382    return ec;
383  if (std::error_code ec = status(B, fsB))
384    return ec;
385  result = equivalent(fsA, fsB);
386  return std::error_code();
387}
388
389static bool isReservedName(StringRef path) {
390  // This list of reserved names comes from MSDN, at:
391  // http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx
392  static const char *const sReservedNames[] = { "nul", "con", "prn", "aux",
393                                                "com1", "com2", "com3", "com4",
394                                                "com5", "com6", "com7", "com8",
395                                                "com9", "lpt1", "lpt2", "lpt3",
396                                                "lpt4", "lpt5", "lpt6", "lpt7",
397                                                "lpt8", "lpt9" };
398
399  // First, check to see if this is a device namespace, which always
400  // starts with \\.\, since device namespaces are not legal file paths.
401  if (path.startswith("\\\\.\\"))
402    return true;
403
404  // Then compare against the list of ancient reserved names.
405  for (size_t i = 0; i < array_lengthof(sReservedNames); ++i) {
406    if (path.equals_lower(sReservedNames[i]))
407      return true;
408  }
409
410  // The path isn't what we consider reserved.
411  return false;
412}
413
414static std::error_code getStatus(HANDLE FileHandle, file_status &Result) {
415  if (FileHandle == INVALID_HANDLE_VALUE)
416    goto handle_status_error;
417
418  switch (::GetFileType(FileHandle)) {
419  default:
420    llvm_unreachable("Don't know anything about this file type");
421  case FILE_TYPE_UNKNOWN: {
422    DWORD Err = ::GetLastError();
423    if (Err != NO_ERROR)
424      return mapWindowsError(Err);
425    Result = file_status(file_type::type_unknown);
426    return std::error_code();
427  }
428  case FILE_TYPE_DISK:
429    break;
430  case FILE_TYPE_CHAR:
431    Result = file_status(file_type::character_file);
432    return std::error_code();
433  case FILE_TYPE_PIPE:
434    Result = file_status(file_type::fifo_file);
435    return std::error_code();
436  }
437
438  BY_HANDLE_FILE_INFORMATION Info;
439  if (!::GetFileInformationByHandle(FileHandle, &Info))
440    goto handle_status_error;
441
442  {
443    file_type Type = (Info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
444                         ? file_type::directory_file
445                         : file_type::regular_file;
446    Result =
447        file_status(Type, Info.ftLastAccessTime.dwHighDateTime,
448                    Info.ftLastAccessTime.dwLowDateTime,
449                    Info.ftLastWriteTime.dwHighDateTime,
450                    Info.ftLastWriteTime.dwLowDateTime,
451                    Info.dwVolumeSerialNumber, Info.nFileSizeHigh,
452                    Info.nFileSizeLow, Info.nFileIndexHigh, Info.nFileIndexLow);
453    return std::error_code();
454  }
455
456handle_status_error:
457  DWORD LastError = ::GetLastError();
458  if (LastError == ERROR_FILE_NOT_FOUND ||
459      LastError == ERROR_PATH_NOT_FOUND)
460    Result = file_status(file_type::file_not_found);
461  else if (LastError == ERROR_SHARING_VIOLATION)
462    Result = file_status(file_type::type_unknown);
463  else
464    Result = file_status(file_type::status_error);
465  return mapWindowsError(LastError);
466}
467
468std::error_code status(const Twine &path, file_status &result) {
469  SmallString<128> path_storage;
470  SmallVector<wchar_t, 128> path_utf16;
471
472  StringRef path8 = path.toStringRef(path_storage);
473  if (isReservedName(path8)) {
474    result = file_status(file_type::character_file);
475    return std::error_code();
476  }
477
478  if (std::error_code ec = widenPath(path8, path_utf16))
479    return ec;
480
481  DWORD attr = ::GetFileAttributesW(path_utf16.begin());
482  if (attr == INVALID_FILE_ATTRIBUTES)
483    return getStatus(INVALID_HANDLE_VALUE, result);
484
485  // Handle reparse points.
486  if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
487    ScopedFileHandle h(
488      ::CreateFileW(path_utf16.begin(),
489                    0, // Attributes only.
490                    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
491                    NULL,
492                    OPEN_EXISTING,
493                    FILE_FLAG_BACKUP_SEMANTICS,
494                    0));
495    if (!h)
496      return getStatus(INVALID_HANDLE_VALUE, result);
497  }
498
499  ScopedFileHandle h(
500      ::CreateFileW(path_utf16.begin(), 0, // Attributes only.
501                    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
502                    NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0));
503    if (!h)
504      return getStatus(INVALID_HANDLE_VALUE, result);
505
506    return getStatus(h, result);
507}
508
509std::error_code status(int FD, file_status &Result) {
510  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
511  return getStatus(FileHandle, Result);
512}
513
514std::error_code setLastModificationAndAccessTime(int FD, TimePoint<> Time) {
515  FILETIME FT = toFILETIME(Time);
516  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
517  if (!SetFileTime(FileHandle, NULL, &FT, &FT))
518    return mapWindowsError(::GetLastError());
519  return std::error_code();
520}
521
522std::error_code mapped_file_region::init(int FD, uint64_t Offset,
523                                         mapmode Mode) {
524  // Make sure that the requested size fits within SIZE_T.
525  if (Size > std::numeric_limits<SIZE_T>::max())
526    return make_error_code(errc::invalid_argument);
527
528  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
529  if (FileHandle == INVALID_HANDLE_VALUE)
530    return make_error_code(errc::bad_file_descriptor);
531
532  DWORD flprotect;
533  switch (Mode) {
534  case readonly:  flprotect = PAGE_READONLY; break;
535  case readwrite: flprotect = PAGE_READWRITE; break;
536  case priv:      flprotect = PAGE_WRITECOPY; break;
537  }
538
539  HANDLE FileMappingHandle =
540      ::CreateFileMappingW(FileHandle, 0, flprotect,
541                           (Offset + Size) >> 32,
542                           (Offset + Size) & 0xffffffff,
543                           0);
544  if (FileMappingHandle == NULL) {
545    std::error_code ec = mapWindowsError(GetLastError());
546    return ec;
547  }
548
549  DWORD dwDesiredAccess;
550  switch (Mode) {
551  case readonly:  dwDesiredAccess = FILE_MAP_READ; break;
552  case readwrite: dwDesiredAccess = FILE_MAP_WRITE; break;
553  case priv:      dwDesiredAccess = FILE_MAP_COPY; break;
554  }
555  Mapping = ::MapViewOfFile(FileMappingHandle,
556                            dwDesiredAccess,
557                            Offset >> 32,
558                            Offset & 0xffffffff,
559                            Size);
560  if (Mapping == NULL) {
561    std::error_code ec = mapWindowsError(GetLastError());
562    ::CloseHandle(FileMappingHandle);
563    return ec;
564  }
565
566  if (Size == 0) {
567    MEMORY_BASIC_INFORMATION mbi;
568    SIZE_T Result = VirtualQuery(Mapping, &mbi, sizeof(mbi));
569    if (Result == 0) {
570      std::error_code ec = mapWindowsError(GetLastError());
571      ::UnmapViewOfFile(Mapping);
572      ::CloseHandle(FileMappingHandle);
573      return ec;
574    }
575    Size = mbi.RegionSize;
576  }
577
578  // Close all the handles except for the view. It will keep the other handles
579  // alive.
580  ::CloseHandle(FileMappingHandle);
581  return std::error_code();
582}
583
584mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length,
585                                       uint64_t offset, std::error_code &ec)
586    : Size(length), Mapping() {
587  ec = init(fd, offset, mode);
588  if (ec)
589    Mapping = 0;
590}
591
592mapped_file_region::~mapped_file_region() {
593  if (Mapping)
594    ::UnmapViewOfFile(Mapping);
595}
596
597uint64_t mapped_file_region::size() const {
598  assert(Mapping && "Mapping failed but used anyway!");
599  return Size;
600}
601
602char *mapped_file_region::data() const {
603  assert(Mapping && "Mapping failed but used anyway!");
604  return reinterpret_cast<char*>(Mapping);
605}
606
607const char *mapped_file_region::const_data() const {
608  assert(Mapping && "Mapping failed but used anyway!");
609  return reinterpret_cast<const char*>(Mapping);
610}
611
612int mapped_file_region::alignment() {
613  SYSTEM_INFO SysInfo;
614  ::GetSystemInfo(&SysInfo);
615  return SysInfo.dwAllocationGranularity;
616}
617
618std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
619                                                StringRef path){
620  SmallVector<wchar_t, 128> path_utf16;
621
622  if (std::error_code ec = widenPath(path, path_utf16))
623    return ec;
624
625  // Convert path to the format that Windows is happy with.
626  if (path_utf16.size() > 0 &&
627      !is_separator(path_utf16[path.size() - 1]) &&
628      path_utf16[path.size() - 1] != L':') {
629    path_utf16.push_back(L'\\');
630    path_utf16.push_back(L'*');
631  } else {
632    path_utf16.push_back(L'*');
633  }
634
635  //  Get the first directory entry.
636  WIN32_FIND_DATAW FirstFind;
637  ScopedFindHandle FindHandle(::FindFirstFileW(c_str(path_utf16), &FirstFind));
638  if (!FindHandle)
639    return mapWindowsError(::GetLastError());
640
641  size_t FilenameLen = ::wcslen(FirstFind.cFileName);
642  while ((FilenameLen == 1 && FirstFind.cFileName[0] == L'.') ||
643         (FilenameLen == 2 && FirstFind.cFileName[0] == L'.' &&
644                              FirstFind.cFileName[1] == L'.'))
645    if (!::FindNextFileW(FindHandle, &FirstFind)) {
646      DWORD LastError = ::GetLastError();
647      // Check for end.
648      if (LastError == ERROR_NO_MORE_FILES)
649        return detail::directory_iterator_destruct(it);
650      return mapWindowsError(LastError);
651    } else
652      FilenameLen = ::wcslen(FirstFind.cFileName);
653
654  // Construct the current directory entry.
655  SmallString<128> directory_entry_name_utf8;
656  if (std::error_code ec =
657          UTF16ToUTF8(FirstFind.cFileName, ::wcslen(FirstFind.cFileName),
658                      directory_entry_name_utf8))
659    return ec;
660
661  it.IterationHandle = intptr_t(FindHandle.take());
662  SmallString<128> directory_entry_path(path);
663  path::append(directory_entry_path, directory_entry_name_utf8);
664  it.CurrentEntry = directory_entry(directory_entry_path);
665
666  return std::error_code();
667}
668
669std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
670  if (it.IterationHandle != 0)
671    // Closes the handle if it's valid.
672    ScopedFindHandle close(HANDLE(it.IterationHandle));
673  it.IterationHandle = 0;
674  it.CurrentEntry = directory_entry();
675  return std::error_code();
676}
677
678std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
679  WIN32_FIND_DATAW FindData;
680  if (!::FindNextFileW(HANDLE(it.IterationHandle), &FindData)) {
681    DWORD LastError = ::GetLastError();
682    // Check for end.
683    if (LastError == ERROR_NO_MORE_FILES)
684      return detail::directory_iterator_destruct(it);
685    return mapWindowsError(LastError);
686  }
687
688  size_t FilenameLen = ::wcslen(FindData.cFileName);
689  if ((FilenameLen == 1 && FindData.cFileName[0] == L'.') ||
690      (FilenameLen == 2 && FindData.cFileName[0] == L'.' &&
691                           FindData.cFileName[1] == L'.'))
692    return directory_iterator_increment(it);
693
694  SmallString<128> directory_entry_path_utf8;
695  if (std::error_code ec =
696          UTF16ToUTF8(FindData.cFileName, ::wcslen(FindData.cFileName),
697                      directory_entry_path_utf8))
698    return ec;
699
700  it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8));
701  return std::error_code();
702}
703
704std::error_code openFileForRead(const Twine &Name, int &ResultFD,
705                                SmallVectorImpl<char> *RealPath) {
706  SmallVector<wchar_t, 128> PathUTF16;
707
708  if (std::error_code EC = widenPath(Name, PathUTF16))
709    return EC;
710
711  HANDLE H =
712      ::CreateFileW(PathUTF16.begin(), GENERIC_READ,
713                    FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
714                    NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
715  if (H == INVALID_HANDLE_VALUE) {
716    DWORD LastError = ::GetLastError();
717    std::error_code EC = mapWindowsError(LastError);
718    // Provide a better error message when trying to open directories.
719    // This only runs if we failed to open the file, so there is probably
720    // no performances issues.
721    if (LastError != ERROR_ACCESS_DENIED)
722      return EC;
723    if (is_directory(Name))
724      return make_error_code(errc::is_a_directory);
725    return EC;
726  }
727
728  int FD = ::_open_osfhandle(intptr_t(H), 0);
729  if (FD == -1) {
730    ::CloseHandle(H);
731    return mapWindowsError(ERROR_INVALID_HANDLE);
732  }
733
734  // Fetch the real name of the file, if the user asked
735  if (RealPath) {
736    RealPath->clear();
737    wchar_t RealPathUTF16[MAX_PATH];
738    DWORD CountChars =
739      ::GetFinalPathNameByHandleW(H, RealPathUTF16, MAX_PATH,
740                                  FILE_NAME_NORMALIZED);
741    if (CountChars > 0 && CountChars < MAX_PATH) {
742      // Convert the result from UTF-16 to UTF-8.
743      SmallString<MAX_PATH> RealPathUTF8;
744      if (!UTF16ToUTF8(RealPathUTF16, CountChars, RealPathUTF8))
745        RealPath->append(RealPathUTF8.data(),
746                         RealPathUTF8.data() + strlen(RealPathUTF8.data()));
747    }
748  }
749
750  ResultFD = FD;
751  return std::error_code();
752}
753
754std::error_code openFileForWrite(const Twine &Name, int &ResultFD,
755                            sys::fs::OpenFlags Flags, unsigned Mode) {
756  // Verify that we don't have both "append" and "excl".
757  assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
758         "Cannot specify both 'excl' and 'append' file creation flags!");
759
760  SmallVector<wchar_t, 128> PathUTF16;
761
762  if (std::error_code EC = widenPath(Name, PathUTF16))
763    return EC;
764
765  DWORD CreationDisposition;
766  if (Flags & F_Excl)
767    CreationDisposition = CREATE_NEW;
768  else if (Flags & F_Append)
769    CreationDisposition = OPEN_ALWAYS;
770  else
771    CreationDisposition = CREATE_ALWAYS;
772
773  DWORD Access = GENERIC_WRITE;
774  if (Flags & F_RW)
775    Access |= GENERIC_READ;
776
777  HANDLE H = ::CreateFileW(PathUTF16.begin(), Access,
778                           FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
779                           CreationDisposition, FILE_ATTRIBUTE_NORMAL, NULL);
780
781  if (H == INVALID_HANDLE_VALUE) {
782    DWORD LastError = ::GetLastError();
783    std::error_code EC = mapWindowsError(LastError);
784    // Provide a better error message when trying to open directories.
785    // This only runs if we failed to open the file, so there is probably
786    // no performances issues.
787    if (LastError != ERROR_ACCESS_DENIED)
788      return EC;
789    if (is_directory(Name))
790      return make_error_code(errc::is_a_directory);
791    return EC;
792  }
793
794  int OpenFlags = 0;
795  if (Flags & F_Append)
796    OpenFlags |= _O_APPEND;
797
798  if (Flags & F_Text)
799    OpenFlags |= _O_TEXT;
800
801  int FD = ::_open_osfhandle(intptr_t(H), OpenFlags);
802  if (FD == -1) {
803    ::CloseHandle(H);
804    return mapWindowsError(ERROR_INVALID_HANDLE);
805  }
806
807  ResultFD = FD;
808  return std::error_code();
809}
810
811std::error_code getPathFromOpenFD(int FD, SmallVectorImpl<char> &ResultPath) {
812  HANDLE FileHandle = reinterpret_cast<HANDLE>(::_get_osfhandle(FD));
813  if (FileHandle == INVALID_HANDLE_VALUE)
814    return make_error_code(errc::bad_file_descriptor);
815
816  DWORD CharCount;
817  SmallVector<wchar_t, 1024> TempPath;
818  do {
819    CharCount = ::GetFinalPathNameByHandleW(FileHandle, TempPath.begin(),
820                                            TempPath.capacity(),
821                                            FILE_NAME_NORMALIZED);
822    if (CharCount < TempPath.capacity())
823      break;
824
825    // Reserve sufficient space for the path as well as the null character. Even
826    // though the API does not document that it is required, if we reserve just
827    // CharCount space, the function call will not store the resulting path and
828    // still report success.
829    TempPath.reserve(CharCount + 1);
830  } while (true);
831
832  if (CharCount == 0)
833    return mapWindowsError(::GetLastError());
834
835  TempPath.set_size(CharCount);
836
837  // On earlier Windows releases, the character count includes the terminating
838  // null.
839  if (TempPath.back() == L'\0') {
840    --CharCount;
841    TempPath.pop_back();
842  }
843
844  return windows::UTF16ToUTF8(TempPath.data(), CharCount, ResultPath);
845}
846} // end namespace fs
847
848namespace path {
849static bool getKnownFolderPath(KNOWNFOLDERID folderId,
850                               SmallVectorImpl<char> &result) {
851  wchar_t *path = nullptr;
852  if (::SHGetKnownFolderPath(folderId, KF_FLAG_CREATE, nullptr, &path) != S_OK)
853    return false;
854
855  bool ok = !UTF16ToUTF8(path, ::wcslen(path), result);
856  ::CoTaskMemFree(path);
857  return ok;
858}
859
860bool getUserCacheDir(SmallVectorImpl<char> &Result) {
861  return getKnownFolderPath(FOLDERID_LocalAppData, Result);
862}
863
864bool home_directory(SmallVectorImpl<char> &result) {
865  return getKnownFolderPath(FOLDERID_Profile, result);
866}
867
868static bool getTempDirEnvVar(const wchar_t *Var, SmallVectorImpl<char> &Res) {
869  SmallVector<wchar_t, 1024> Buf;
870  size_t Size = 1024;
871  do {
872    Buf.reserve(Size);
873    Size = GetEnvironmentVariableW(Var, Buf.data(), Buf.capacity());
874    if (Size == 0)
875      return false;
876
877    // Try again with larger buffer.
878  } while (Size > Buf.capacity());
879  Buf.set_size(Size);
880
881  return !windows::UTF16ToUTF8(Buf.data(), Size, Res);
882}
883
884static bool getTempDirEnvVar(SmallVectorImpl<char> &Res) {
885  const wchar_t *EnvironmentVariables[] = {L"TMP", L"TEMP", L"USERPROFILE"};
886  for (auto *Env : EnvironmentVariables) {
887    if (getTempDirEnvVar(Env, Res))
888      return true;
889  }
890  return false;
891}
892
893void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
894  (void)ErasedOnReboot;
895  Result.clear();
896
897  // Check whether the temporary directory is specified by an environment var.
898  // This matches GetTempPath logic to some degree. GetTempPath is not used
899  // directly as it cannot handle evn var longer than 130 chars on Windows 7
900  // (fixed on Windows 8).
901  if (getTempDirEnvVar(Result)) {
902    assert(!Result.empty() && "Unexpected empty path");
903    native(Result); // Some Unix-like shells use Unix path separator in $TMP.
904    fs::make_absolute(Result); // Make it absolute if not already.
905    return;
906  }
907
908  // Fall back to a system default.
909  const char *DefaultResult = "C:\\Temp";
910  Result.append(DefaultResult, DefaultResult + strlen(DefaultResult));
911}
912} // end namespace path
913
914namespace windows {
915std::error_code UTF8ToUTF16(llvm::StringRef utf8,
916                            llvm::SmallVectorImpl<wchar_t> &utf16) {
917  if (!utf8.empty()) {
918    int len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, utf8.begin(),
919                                    utf8.size(), utf16.begin(), 0);
920
921    if (len == 0)
922      return mapWindowsError(::GetLastError());
923
924    utf16.reserve(len + 1);
925    utf16.set_size(len);
926
927    len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, utf8.begin(),
928                                utf8.size(), utf16.begin(), utf16.size());
929
930    if (len == 0)
931      return mapWindowsError(::GetLastError());
932  }
933
934  // Make utf16 null terminated.
935  utf16.push_back(0);
936  utf16.pop_back();
937
938  return std::error_code();
939}
940
941static
942std::error_code UTF16ToCodePage(unsigned codepage, const wchar_t *utf16,
943                                size_t utf16_len,
944                                llvm::SmallVectorImpl<char> &utf8) {
945  if (utf16_len) {
946    // Get length.
947    int len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, utf8.begin(),
948                                    0, NULL, NULL);
949
950    if (len == 0)
951      return mapWindowsError(::GetLastError());
952
953    utf8.reserve(len);
954    utf8.set_size(len);
955
956    // Now do the actual conversion.
957    len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, utf8.data(),
958                                utf8.size(), NULL, NULL);
959
960    if (len == 0)
961      return mapWindowsError(::GetLastError());
962  }
963
964  // Make utf8 null terminated.
965  utf8.push_back(0);
966  utf8.pop_back();
967
968  return std::error_code();
969}
970
971std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
972                            llvm::SmallVectorImpl<char> &utf8) {
973  return UTF16ToCodePage(CP_UTF8, utf16, utf16_len, utf8);
974}
975
976std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len,
977                             llvm::SmallVectorImpl<char> &utf8) {
978  return UTF16ToCodePage(CP_ACP, utf16, utf16_len, utf8);
979}
980
981} // end namespace windows
982} // end namespace sys
983} // end namespace llvm
984