Path.inc revision ebe69fe11e48d322045d5949c83283927a0d790b 
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#endif
42
43using namespace llvm;
44
45using llvm::sys::windows::UTF8ToUTF16;
46using llvm::sys::windows::UTF16ToUTF8;
47using llvm::sys::path::widenPath;
48
49static std::error_code windows_error(DWORD E) {
50  return mapWindowsError(E);
51}
52
53static bool is_separator(const wchar_t value) {
54  switch (value) {
55  case L'\\':
56  case L'/':
57    return true;
58  default:
59    return false;
60  }
61}
62
63namespace llvm {
64namespace sys  {
65namespace path {
66
67// Convert a UTF-8 path to UTF-16.  Also, if the absolute equivalent of the
68// path is longer than CreateDirectory can tolerate, make it absolute and
69// prefixed by '\\?\'.
70std::error_code widenPath(const Twine &Path8,
71                          SmallVectorImpl<wchar_t> &Path16) {
72  const size_t MaxDirLen = MAX_PATH - 12; // Must leave room for 8.3 filename.
73
74  // Several operations would convert Path8 to SmallString; more efficient to
75  // do it once up front.
76  SmallString<128> Path8Str;
77  Path8.toVector(Path8Str);
78
79  // If we made this path absolute, how much longer would it get?
80  size_t CurPathLen;
81  if (llvm::sys::path::is_absolute(Twine(Path8Str)))
82    CurPathLen = 0; // No contribution from current_path needed.
83  else {
84    CurPathLen = ::GetCurrentDirectoryW(0, NULL);
85    if (CurPathLen == 0)
86      return windows_error(::GetLastError());
87  }
88
89  // Would the absolute path be longer than our limit?
90  if ((Path8Str.size() + CurPathLen) >= MaxDirLen &&
91      !Path8Str.startswith("\\\\?\\")) {
92    SmallString<2*MAX_PATH> FullPath("\\\\?\\");
93    if (CurPathLen) {
94      SmallString<80> CurPath;
95      if (std::error_code EC = llvm::sys::fs::current_path(CurPath))
96        return EC;
97      FullPath.append(CurPath);
98    }
99    // Traverse the requested path, canonicalizing . and .. as we go (because
100    // the \\?\ prefix is documented to treat them as real components).
101    // The iterators don't report separators and append() always attaches
102    // preferred_separator so we don't need to call native() on the result.
103    for (llvm::sys::path::const_iterator I = llvm::sys::path::begin(Path8Str),
104                                         E = llvm::sys::path::end(Path8Str);
105                                         I != E; ++I) {
106      if (I->size() == 1 && *I == ".")
107        continue;
108      if (I->size() == 2 && *I == "..")
109        llvm::sys::path::remove_filename(FullPath);
110      else
111        llvm::sys::path::append(FullPath, *I);
112    }
113    return UTF8ToUTF16(FullPath, Path16);
114  }
115
116  // Just use the caller's original path.
117  return UTF8ToUTF16(Path8Str, Path16);
118}
119} // end namespace path
120
121namespace fs {
122
123std::string getMainExecutable(const char *argv0, void *MainExecAddr) {
124  SmallVector<wchar_t, MAX_PATH> PathName;
125  DWORD Size = ::GetModuleFileNameW(NULL, PathName.data(), PathName.capacity());
126
127  // A zero return value indicates a failure other than insufficient space.
128  if (Size == 0)
129    return "";
130
131  // Insufficient space is determined by a return value equal to the size of
132  // the buffer passed in.
133  if (Size == PathName.capacity())
134    return "";
135
136  // On success, GetModuleFileNameW returns the number of characters written to
137  // the buffer not including the NULL terminator.
138  PathName.set_size(Size);
139
140  // Convert the result from UTF-16 to UTF-8.
141  SmallVector<char, MAX_PATH> PathNameUTF8;
142  if (UTF16ToUTF8(PathName.data(), PathName.size(), PathNameUTF8))
143    return "";
144
145  return std::string(PathNameUTF8.data());
146}
147
148UniqueID file_status::getUniqueID() const {
149  // The file is uniquely identified by the volume serial number along
150  // with the 64-bit file identifier.
151  uint64_t FileID = (static_cast<uint64_t>(FileIndexHigh) << 32ULL) |
152                    static_cast<uint64_t>(FileIndexLow);
153
154  return UniqueID(VolumeSerialNumber, FileID);
155}
156
157TimeValue file_status::getLastModificationTime() const {
158  ULARGE_INTEGER UI;
159  UI.LowPart = LastWriteTimeLow;
160  UI.HighPart = LastWriteTimeHigh;
161
162  TimeValue Ret;
163  Ret.fromWin32Time(UI.QuadPart);
164  return Ret;
165}
166
167std::error_code current_path(SmallVectorImpl<char> &result) {
168  SmallVector<wchar_t, MAX_PATH> cur_path;
169  DWORD len = MAX_PATH;
170
171  do {
172    cur_path.reserve(len);
173    len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
174
175    // A zero return value indicates a failure other than insufficient space.
176    if (len == 0)
177      return windows_error(::GetLastError());
178
179    // If there's insufficient space, the len returned is larger than the len
180    // given.
181  } while (len > cur_path.capacity());
182
183  // On success, GetCurrentDirectoryW returns the number of characters not
184  // including the null-terminator.
185  cur_path.set_size(len);
186  return UTF16ToUTF8(cur_path.begin(), cur_path.size(), result);
187}
188
189std::error_code create_directory(const Twine &path, bool IgnoreExisting) {
190  SmallVector<wchar_t, 128> path_utf16;
191
192  if (std::error_code ec = widenPath(path, path_utf16))
193    return ec;
194
195  if (!::CreateDirectoryW(path_utf16.begin(), NULL)) {
196    DWORD LastError = ::GetLastError();
197    if (LastError != ERROR_ALREADY_EXISTS || !IgnoreExisting)
198      return windows_error(LastError);
199  }
200
201  return std::error_code();
202}
203
204// We can't use symbolic links for windows.
205std::error_code create_link(const Twine &to, const Twine &from) {
206  // Convert to utf-16.
207  SmallVector<wchar_t, 128> wide_from;
208  SmallVector<wchar_t, 128> wide_to;
209  if (std::error_code ec = widenPath(from, wide_from))
210    return ec;
211  if (std::error_code ec = widenPath(to, wide_to))
212    return ec;
213
214  if (!::CreateHardLinkW(wide_from.begin(), wide_to.begin(), NULL))
215    return windows_error(::GetLastError());
216
217  return std::error_code();
218}
219
220std::error_code remove(const Twine &path, bool IgnoreNonExisting) {
221  SmallVector<wchar_t, 128> path_utf16;
222
223  file_status ST;
224  if (std::error_code EC = status(path, ST)) {
225    if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
226      return EC;
227    return std::error_code();
228  }
229
230  if (std::error_code ec = widenPath(path, path_utf16))
231    return ec;
232
233  if (ST.type() == file_type::directory_file) {
234    if (!::RemoveDirectoryW(c_str(path_utf16))) {
235      std::error_code EC = windows_error(::GetLastError());
236      if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
237        return EC;
238    }
239    return std::error_code();
240  }
241  if (!::DeleteFileW(c_str(path_utf16))) {
242    std::error_code EC = windows_error(::GetLastError());
243    if (EC != errc::no_such_file_or_directory || !IgnoreNonExisting)
244      return EC;
245  }
246  return std::error_code();
247}
248
249std::error_code rename(const Twine &from, const Twine &to) {
250  // Convert to utf-16.
251  SmallVector<wchar_t, 128> wide_from;
252  SmallVector<wchar_t, 128> wide_to;
253  if (std::error_code ec = widenPath(from, wide_from))
254    return ec;
255  if (std::error_code ec = widenPath(to, wide_to))
256    return ec;
257
258  std::error_code ec = std::error_code();
259  for (int i = 0; i < 2000; i++) {
260    if (::MoveFileExW(wide_from.begin(), wide_to.begin(),
261                      MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING))
262      return std::error_code();
263    DWORD LastError = ::GetLastError();
264    if (LastError != ERROR_ACCESS_DENIED)
265      break;
266    // Retry MoveFile() at ACCESS_DENIED.
267    // System scanners (eg. indexer) might open the source file when
268    // It is written and closed.
269    ::Sleep(1);
270  }
271
272  return ec;
273}
274
275std::error_code resize_file(int FD, uint64_t Size) {
276#ifdef HAVE__CHSIZE_S
277  errno_t error = ::_chsize_s(FD, Size);
278#else
279  errno_t error = ::_chsize(FD, Size);
280#endif
281  return std::error_code(error, std::generic_category());
282}
283
284std::error_code access(const Twine &Path, AccessMode Mode) {
285  SmallVector<wchar_t, 128> PathUtf16;
286
287  if (std::error_code EC = widenPath(Path, PathUtf16))
288    return EC;
289
290  DWORD Attributes = ::GetFileAttributesW(PathUtf16.begin());
291
292  if (Attributes == INVALID_FILE_ATTRIBUTES) {
293    // See if the file didn't actually exist.
294    DWORD LastError = ::GetLastError();
295    if (LastError != ERROR_FILE_NOT_FOUND &&
296        LastError != ERROR_PATH_NOT_FOUND)
297      return windows_error(LastError);
298    return errc::no_such_file_or_directory;
299  }
300
301  if (Mode == AccessMode::Write && (Attributes & FILE_ATTRIBUTE_READONLY))
302    return errc::permission_denied;
303
304  return std::error_code();
305}
306
307bool equivalent(file_status A, file_status B) {
308  assert(status_known(A) && status_known(B));
309  return A.FileIndexHigh      == B.FileIndexHigh &&
310         A.FileIndexLow       == B.FileIndexLow &&
311         A.FileSizeHigh       == B.FileSizeHigh &&
312         A.FileSizeLow        == B.FileSizeLow &&
313         A.LastWriteTimeHigh  == B.LastWriteTimeHigh &&
314         A.LastWriteTimeLow   == B.LastWriteTimeLow &&
315         A.VolumeSerialNumber == B.VolumeSerialNumber;
316}
317
318std::error_code equivalent(const Twine &A, const Twine &B, bool &result) {
319  file_status fsA, fsB;
320  if (std::error_code ec = status(A, fsA))
321    return ec;
322  if (std::error_code ec = status(B, fsB))
323    return ec;
324  result = equivalent(fsA, fsB);
325  return std::error_code();
326}
327
328static bool isReservedName(StringRef path) {
329  // This list of reserved names comes from MSDN, at:
330  // http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx
331  static const char *sReservedNames[] = { "nul", "con", "prn", "aux",
332                              "com1", "com2", "com3", "com4", "com5", "com6",
333                              "com7", "com8", "com9", "lpt1", "lpt2", "lpt3",
334                              "lpt4", "lpt5", "lpt6", "lpt7", "lpt8", "lpt9" };
335
336  // First, check to see if this is a device namespace, which always
337  // starts with \\.\, since device namespaces are not legal file paths.
338  if (path.startswith("\\\\.\\"))
339    return true;
340
341  // Then compare against the list of ancient reserved names
342  for (size_t i = 0; i < array_lengthof(sReservedNames); ++i) {
343    if (path.equals_lower(sReservedNames[i]))
344      return true;
345  }
346
347  // The path isn't what we consider reserved.
348  return false;
349}
350
351static std::error_code getStatus(HANDLE FileHandle, file_status &Result) {
352  if (FileHandle == INVALID_HANDLE_VALUE)
353    goto handle_status_error;
354
355  switch (::GetFileType(FileHandle)) {
356  default:
357    llvm_unreachable("Don't know anything about this file type");
358  case FILE_TYPE_UNKNOWN: {
359    DWORD Err = ::GetLastError();
360    if (Err != NO_ERROR)
361      return windows_error(Err);
362    Result = file_status(file_type::type_unknown);
363    return std::error_code();
364  }
365  case FILE_TYPE_DISK:
366    break;
367  case FILE_TYPE_CHAR:
368    Result = file_status(file_type::character_file);
369    return std::error_code();
370  case FILE_TYPE_PIPE:
371    Result = file_status(file_type::fifo_file);
372    return std::error_code();
373  }
374
375  BY_HANDLE_FILE_INFORMATION Info;
376  if (!::GetFileInformationByHandle(FileHandle, &Info))
377    goto handle_status_error;
378
379  {
380    file_type Type = (Info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
381                         ? file_type::directory_file
382                         : file_type::regular_file;
383    Result =
384        file_status(Type, Info.ftLastWriteTime.dwHighDateTime,
385                    Info.ftLastWriteTime.dwLowDateTime,
386                    Info.dwVolumeSerialNumber, Info.nFileSizeHigh,
387                    Info.nFileSizeLow, Info.nFileIndexHigh, Info.nFileIndexLow);
388    return std::error_code();
389  }
390
391handle_status_error:
392  DWORD LastError = ::GetLastError();
393  if (LastError == ERROR_FILE_NOT_FOUND ||
394      LastError == ERROR_PATH_NOT_FOUND)
395    Result = file_status(file_type::file_not_found);
396  else if (LastError == ERROR_SHARING_VIOLATION)
397    Result = file_status(file_type::type_unknown);
398  else
399    Result = file_status(file_type::status_error);
400  return windows_error(LastError);
401}
402
403std::error_code status(const Twine &path, file_status &result) {
404  SmallString<128> path_storage;
405  SmallVector<wchar_t, 128> path_utf16;
406
407  StringRef path8 = path.toStringRef(path_storage);
408  if (isReservedName(path8)) {
409    result = file_status(file_type::character_file);
410    return std::error_code();
411  }
412
413  if (std::error_code ec = widenPath(path8, path_utf16))
414    return ec;
415
416  DWORD attr = ::GetFileAttributesW(path_utf16.begin());
417  if (attr == INVALID_FILE_ATTRIBUTES)
418    return getStatus(INVALID_HANDLE_VALUE, result);
419
420  // Handle reparse points.
421  if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
422    ScopedFileHandle h(
423      ::CreateFileW(path_utf16.begin(),
424                    0, // Attributes only.
425                    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
426                    NULL,
427                    OPEN_EXISTING,
428                    FILE_FLAG_BACKUP_SEMANTICS,
429                    0));
430    if (!h)
431      return getStatus(INVALID_HANDLE_VALUE, result);
432  }
433
434  ScopedFileHandle h(
435      ::CreateFileW(path_utf16.begin(), 0, // Attributes only.
436                    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
437                    NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0));
438    if (!h)
439      return getStatus(INVALID_HANDLE_VALUE, result);
440
441    return getStatus(h, result);
442}
443
444std::error_code status(int FD, file_status &Result) {
445  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
446  return getStatus(FileHandle, Result);
447}
448
449std::error_code setLastModificationAndAccessTime(int FD, TimeValue Time) {
450  ULARGE_INTEGER UI;
451  UI.QuadPart = Time.toWin32Time();
452  FILETIME FT;
453  FT.dwLowDateTime = UI.LowPart;
454  FT.dwHighDateTime = UI.HighPart;
455  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
456  if (!SetFileTime(FileHandle, NULL, &FT, &FT))
457    return windows_error(::GetLastError());
458  return std::error_code();
459}
460
461std::error_code mapped_file_region::init(int FD, uint64_t Offset,
462                                         mapmode Mode) {
463  // Make sure that the requested size fits within SIZE_T.
464  if (Size > std::numeric_limits<SIZE_T>::max())
465    return make_error_code(errc::invalid_argument);
466
467  HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
468  if (FileHandle == INVALID_HANDLE_VALUE)
469    return make_error_code(errc::bad_file_descriptor);
470
471  DWORD flprotect;
472  switch (Mode) {
473  case readonly:  flprotect = PAGE_READONLY; break;
474  case readwrite: flprotect = PAGE_READWRITE; break;
475  case priv:      flprotect = PAGE_WRITECOPY; break;
476  }
477
478  HANDLE FileMappingHandle =
479      ::CreateFileMappingW(FileHandle, 0, flprotect,
480                           (Offset + Size) >> 32,
481                           (Offset + Size) & 0xffffffff,
482                           0);
483  if (FileMappingHandle == NULL) {
484    std::error_code ec = windows_error(GetLastError());
485    return ec;
486  }
487
488  DWORD dwDesiredAccess;
489  switch (Mode) {
490  case readonly:  dwDesiredAccess = FILE_MAP_READ; break;
491  case readwrite: dwDesiredAccess = FILE_MAP_WRITE; break;
492  case priv:      dwDesiredAccess = FILE_MAP_COPY; break;
493  }
494  Mapping = ::MapViewOfFile(FileMappingHandle,
495                            dwDesiredAccess,
496                            Offset >> 32,
497                            Offset & 0xffffffff,
498                            Size);
499  if (Mapping == NULL) {
500    std::error_code ec = windows_error(GetLastError());
501    ::CloseHandle(FileMappingHandle);
502    return ec;
503  }
504
505  if (Size == 0) {
506    MEMORY_BASIC_INFORMATION mbi;
507    SIZE_T Result = VirtualQuery(Mapping, &mbi, sizeof(mbi));
508    if (Result == 0) {
509      std::error_code ec = windows_error(GetLastError());
510      ::UnmapViewOfFile(Mapping);
511      ::CloseHandle(FileMappingHandle);
512      return ec;
513    }
514    Size = mbi.RegionSize;
515  }
516
517  // Close all the handles except for the view. It will keep the other handles
518  // alive.
519  ::CloseHandle(FileMappingHandle);
520  return std::error_code();
521}
522
523mapped_file_region::mapped_file_region(int fd, mapmode mode, uint64_t length,
524                                       uint64_t offset, std::error_code &ec)
525    : Size(length), Mapping() {
526  ec = init(fd, offset, mode);
527  if (ec)
528    Mapping = 0;
529}
530
531mapped_file_region::~mapped_file_region() {
532  if (Mapping)
533    ::UnmapViewOfFile(Mapping);
534}
535
536uint64_t mapped_file_region::size() const {
537  assert(Mapping && "Mapping failed but used anyway!");
538  return Size;
539}
540
541char *mapped_file_region::data() const {
542  assert(Mapping && "Mapping failed but used anyway!");
543  return reinterpret_cast<char*>(Mapping);
544}
545
546const char *mapped_file_region::const_data() const {
547  assert(Mapping && "Mapping failed but used anyway!");
548  return reinterpret_cast<const char*>(Mapping);
549}
550
551int mapped_file_region::alignment() {
552  SYSTEM_INFO SysInfo;
553  ::GetSystemInfo(&SysInfo);
554  return SysInfo.dwAllocationGranularity;
555}
556
557std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
558                                                StringRef path){
559  SmallVector<wchar_t, 128> path_utf16;
560
561  if (std::error_code ec = widenPath(path, path_utf16))
562    return ec;
563
564  // Convert path to the format that Windows is happy with.
565  if (path_utf16.size() > 0 &&
566      !is_separator(path_utf16[path.size() - 1]) &&
567      path_utf16[path.size() - 1] != L':') {
568    path_utf16.push_back(L'\\');
569    path_utf16.push_back(L'*');
570  } else {
571    path_utf16.push_back(L'*');
572  }
573
574  //  Get the first directory entry.
575  WIN32_FIND_DATAW FirstFind;
576  ScopedFindHandle FindHandle(::FindFirstFileW(c_str(path_utf16), &FirstFind));
577  if (!FindHandle)
578    return windows_error(::GetLastError());
579
580  size_t FilenameLen = ::wcslen(FirstFind.cFileName);
581  while ((FilenameLen == 1 && FirstFind.cFileName[0] == L'.') ||
582         (FilenameLen == 2 && FirstFind.cFileName[0] == L'.' &&
583                              FirstFind.cFileName[1] == L'.'))
584    if (!::FindNextFileW(FindHandle, &FirstFind)) {
585      DWORD LastError = ::GetLastError();
586      // Check for end.
587      if (LastError == ERROR_NO_MORE_FILES)
588        return detail::directory_iterator_destruct(it);
589      return windows_error(LastError);
590    } else
591      FilenameLen = ::wcslen(FirstFind.cFileName);
592
593  // Construct the current directory entry.
594  SmallString<128> directory_entry_name_utf8;
595  if (std::error_code ec =
596          UTF16ToUTF8(FirstFind.cFileName, ::wcslen(FirstFind.cFileName),
597                      directory_entry_name_utf8))
598    return ec;
599
600  it.IterationHandle = intptr_t(FindHandle.take());
601  SmallString<128> directory_entry_path(path);
602  path::append(directory_entry_path, directory_entry_name_utf8.str());
603  it.CurrentEntry = directory_entry(directory_entry_path.str());
604
605  return std::error_code();
606}
607
608std::error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
609  if (it.IterationHandle != 0)
610    // Closes the handle if it's valid.
611    ScopedFindHandle close(HANDLE(it.IterationHandle));
612  it.IterationHandle = 0;
613  it.CurrentEntry = directory_entry();
614  return std::error_code();
615}
616
617std::error_code detail::directory_iterator_increment(detail::DirIterState &it) {
618  WIN32_FIND_DATAW FindData;
619  if (!::FindNextFileW(HANDLE(it.IterationHandle), &FindData)) {
620    DWORD LastError = ::GetLastError();
621    // Check for end.
622    if (LastError == ERROR_NO_MORE_FILES)
623      return detail::directory_iterator_destruct(it);
624    return windows_error(LastError);
625  }
626
627  size_t FilenameLen = ::wcslen(FindData.cFileName);
628  if ((FilenameLen == 1 && FindData.cFileName[0] == L'.') ||
629      (FilenameLen == 2 && FindData.cFileName[0] == L'.' &&
630                           FindData.cFileName[1] == L'.'))
631    return directory_iterator_increment(it);
632
633  SmallString<128> directory_entry_path_utf8;
634  if (std::error_code ec =
635          UTF16ToUTF8(FindData.cFileName, ::wcslen(FindData.cFileName),
636                      directory_entry_path_utf8))
637    return ec;
638
639  it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8));
640  return std::error_code();
641}
642
643std::error_code openFileForRead(const Twine &Name, int &ResultFD) {
644  SmallVector<wchar_t, 128> PathUTF16;
645
646  if (std::error_code EC = widenPath(Name, PathUTF16))
647    return EC;
648
649  HANDLE H = ::CreateFileW(PathUTF16.begin(), GENERIC_READ,
650                           FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
651                           OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
652  if (H == INVALID_HANDLE_VALUE) {
653    DWORD LastError = ::GetLastError();
654    std::error_code EC = windows_error(LastError);
655    // Provide a better error message when trying to open directories.
656    // This only runs if we failed to open the file, so there is probably
657    // no performances issues.
658    if (LastError != ERROR_ACCESS_DENIED)
659      return EC;
660    if (is_directory(Name))
661      return make_error_code(errc::is_a_directory);
662    return EC;
663  }
664
665  int FD = ::_open_osfhandle(intptr_t(H), 0);
666  if (FD == -1) {
667    ::CloseHandle(H);
668    return windows_error(ERROR_INVALID_HANDLE);
669  }
670
671  ResultFD = FD;
672  return std::error_code();
673}
674
675std::error_code openFileForWrite(const Twine &Name, int &ResultFD,
676                            sys::fs::OpenFlags Flags, unsigned Mode) {
677  // Verify that we don't have both "append" and "excl".
678  assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
679         "Cannot specify both 'excl' and 'append' file creation flags!");
680
681  SmallVector<wchar_t, 128> PathUTF16;
682
683  if (std::error_code EC = widenPath(Name, PathUTF16))
684    return EC;
685
686  DWORD CreationDisposition;
687  if (Flags & F_Excl)
688    CreationDisposition = CREATE_NEW;
689  else if (Flags & F_Append)
690    CreationDisposition = OPEN_ALWAYS;
691  else
692    CreationDisposition = CREATE_ALWAYS;
693
694  DWORD Access = GENERIC_WRITE;
695  if (Flags & F_RW)
696    Access |= GENERIC_READ;
697
698  HANDLE H = ::CreateFileW(PathUTF16.begin(), Access,
699                           FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
700                           CreationDisposition, FILE_ATTRIBUTE_NORMAL, NULL);
701
702  if (H == INVALID_HANDLE_VALUE) {
703    DWORD LastError = ::GetLastError();
704    std::error_code EC = windows_error(LastError);
705    // Provide a better error message when trying to open directories.
706    // This only runs if we failed to open the file, so there is probably
707    // no performances issues.
708    if (LastError != ERROR_ACCESS_DENIED)
709      return EC;
710    if (is_directory(Name))
711      return make_error_code(errc::is_a_directory);
712    return EC;
713  }
714
715  int OpenFlags = 0;
716  if (Flags & F_Append)
717    OpenFlags |= _O_APPEND;
718
719  if (Flags & F_Text)
720    OpenFlags |= _O_TEXT;
721
722  int FD = ::_open_osfhandle(intptr_t(H), OpenFlags);
723  if (FD == -1) {
724    ::CloseHandle(H);
725    return windows_error(ERROR_INVALID_HANDLE);
726  }
727
728  ResultFD = FD;
729  return std::error_code();
730}
731} // end namespace fs
732
733namespace path {
734
735bool home_directory(SmallVectorImpl<char> &result) {
736  wchar_t Path[MAX_PATH];
737  if (::SHGetFolderPathW(0, CSIDL_APPDATA | CSIDL_FLAG_CREATE, 0,
738                         /*SHGFP_TYPE_CURRENT*/0, Path) != S_OK)
739    return false;
740
741  if (UTF16ToUTF8(Path, ::wcslen(Path), result))
742    return false;
743
744  return true;
745}
746
747static bool getTempDirEnvVar(const char *Var, SmallVectorImpl<char> &Res) {
748  SmallVector<wchar_t, 128> NameUTF16;
749  if (windows::UTF8ToUTF16(Var, NameUTF16))
750    return false;
751
752  SmallVector<wchar_t, 1024> Buf;
753  size_t Size = 1024;
754  do {
755    Buf.reserve(Size);
756    Size =
757        GetEnvironmentVariableW(NameUTF16.data(), Buf.data(), Buf.capacity());
758    if (Size == 0)
759      return false;
760
761    // Try again with larger buffer.
762  } while (Size > Buf.capacity());
763  Buf.set_size(Size);
764
765  if (windows::UTF16ToUTF8(Buf.data(), Size, Res))
766    return false;
767  return true;
768}
769
770static bool getTempDirEnvVar(SmallVectorImpl<char> &Res) {
771  const char *EnvironmentVariables[] = {"TMP", "TEMP", "USERPROFILE"};
772  for (const char *Env : EnvironmentVariables) {
773    if (getTempDirEnvVar(Env, Res))
774      return true;
775  }
776  return false;
777}
778
779void system_temp_directory(bool ErasedOnReboot, SmallVectorImpl<char> &Result) {
780  (void)ErasedOnReboot;
781  Result.clear();
782
783  // Check whether the temporary directory is specified by an environment
784  // variable.
785  if (getTempDirEnvVar(Result))
786    return;
787
788  // Fall back to a system default.
789  const char *DefaultResult = "C:\\TEMP";
790  Result.append(DefaultResult, DefaultResult + strlen(DefaultResult));
791}
792} // end namespace path
793
794namespace windows {
795std::error_code UTF8ToUTF16(llvm::StringRef utf8,
796                            llvm::SmallVectorImpl<wchar_t> &utf16) {
797  if (!utf8.empty()) {
798    int len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, utf8.begin(),
799                                    utf8.size(), utf16.begin(), 0);
800
801    if (len == 0)
802      return windows_error(::GetLastError());
803
804    utf16.reserve(len + 1);
805    utf16.set_size(len);
806
807    len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS, utf8.begin(),
808                                utf8.size(), utf16.begin(), utf16.size());
809
810    if (len == 0)
811      return windows_error(::GetLastError());
812  }
813
814  // Make utf16 null terminated.
815  utf16.push_back(0);
816  utf16.pop_back();
817
818  return std::error_code();
819}
820
821static
822std::error_code UTF16ToCodePage(unsigned codepage, const wchar_t *utf16,
823                                size_t utf16_len,
824                                llvm::SmallVectorImpl<char> &utf8) {
825  if (utf16_len) {
826    // Get length.
827    int len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, utf8.begin(),
828                                    0, NULL, NULL);
829
830    if (len == 0)
831      return windows_error(::GetLastError());
832
833    utf8.reserve(len);
834    utf8.set_size(len);
835
836    // Now do the actual conversion.
837    len = ::WideCharToMultiByte(codepage, 0, utf16, utf16_len, utf8.data(),
838                                utf8.size(), NULL, NULL);
839
840    if (len == 0)
841      return windows_error(::GetLastError());
842  }
843
844  // Make utf8 null terminated.
845  utf8.push_back(0);
846  utf8.pop_back();
847
848  return std::error_code();
849}
850
851std::error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
852                            llvm::SmallVectorImpl<char> &utf8) {
853  return UTF16ToCodePage(CP_UTF8, utf16, utf16_len, utf8);
854}
855
856std::error_code UTF16ToCurCP(const wchar_t *utf16, size_t utf16_len,
857                             llvm::SmallVectorImpl<char> &utf8) {
858  return UTF16ToCodePage(CP_ACP, utf16, utf16_len, utf8);
859}
860} // end namespace windows
861} // end namespace sys
862} // end namespace llvm
863