PathV2.inc revision 5029159fbe7c267c9322fc6c38064e9ab2ce91bc 
1//===- llvm/Support/Win32/PathV2.cpp - 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 PathV2 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 "Windows.h"
20#include <WinCrypt.h>
21#include <fcntl.h>
22#include <io.h>
23#include <sys/stat.h>
24#include <sys/types.h>
25
26// MinGW doesn't define this.
27#ifndef _ERRNO_T_DEFINED
28#define _ERRNO_T_DEFINED
29typedef int errno_t;
30#endif
31
32using namespace llvm;
33
34namespace {
35  typedef BOOLEAN (WINAPI *PtrCreateSymbolicLinkW)(
36    /*__in*/ LPCWSTR lpSymlinkFileName,
37    /*__in*/ LPCWSTR lpTargetFileName,
38    /*__in*/ DWORD dwFlags);
39
40  PtrCreateSymbolicLinkW create_symbolic_link_api = PtrCreateSymbolicLinkW(
41    ::GetProcAddress(::GetModuleHandleA("kernel32.dll"),
42                     "CreateSymbolicLinkW"));
43
44  error_code UTF8ToUTF16(const StringRef &utf8,
45                               SmallVectorImpl<wchar_t> &utf16) {
46    int len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
47                                    utf8.begin(), utf8.size(),
48                                    utf16.begin(), 0);
49
50    if (len == 0)
51      return windows_error(::GetLastError());
52
53    utf16.reserve(len + 1);
54    utf16.set_size(len);
55
56    len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
57                                    utf8.begin(), utf8.size(),
58                                    utf16.begin(), utf16.size());
59
60    if (len == 0)
61      return windows_error(::GetLastError());
62
63    // Make utf16 null terminated.
64    utf16.push_back(0);
65    utf16.pop_back();
66
67    return success;
68  }
69
70  error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
71                               SmallVectorImpl<char> &utf8) {
72    // Get length.
73    int len = ::WideCharToMultiByte(CP_UTF8, 0,
74                                    utf16, utf16_len,
75                                    utf8.begin(), 0,
76                                    NULL, NULL);
77
78    if (len == 0)
79      return windows_error(::GetLastError());
80
81    utf8.reserve(len);
82    utf8.set_size(len);
83
84    // Now do the actual conversion.
85    len = ::WideCharToMultiByte(CP_UTF8, 0,
86                                utf16, utf16_len,
87                                utf8.data(), utf8.size(),
88                                NULL, NULL);
89
90    if (len == 0)
91      return windows_error(::GetLastError());
92
93    // Make utf8 null terminated.
94    utf8.push_back(0);
95    utf8.pop_back();
96
97    return success;
98  }
99
100  error_code TempDir(SmallVectorImpl<wchar_t> &result) {
101  retry_temp_dir:
102    DWORD len = ::GetTempPathW(result.capacity(), result.begin());
103
104    if (len == 0)
105      return windows_error(::GetLastError());
106
107    if (len > result.capacity()) {
108      result.reserve(len);
109      goto retry_temp_dir;
110    }
111
112    result.set_size(len);
113    return success;
114  }
115
116  // Forwarder for ScopedHandle.
117  BOOL WINAPI CryptReleaseContext(HCRYPTPROV Provider) {
118    return ::CryptReleaseContext(Provider, 0);
119  }
120
121  typedef ScopedHandle<HCRYPTPROV, uintptr_t(-1),
122                       BOOL (WINAPI*)(HCRYPTPROV), CryptReleaseContext>
123    ScopedCryptContext;
124  bool is_separator(const wchar_t value) {
125    switch (value) {
126    case L'\\':
127    case L'/':
128      return true;
129    default:
130      return false;
131    }
132  }
133}
134
135namespace llvm {
136namespace sys  {
137namespace fs {
138
139error_code current_path(SmallVectorImpl<char> &result) {
140  SmallVector<wchar_t, 128> cur_path;
141  cur_path.reserve(128);
142retry_cur_dir:
143  DWORD len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
144
145  // A zero return value indicates a failure other than insufficient space.
146  if (len == 0)
147    return windows_error(::GetLastError());
148
149  // If there's insufficient space, the len returned is larger than the len
150  // given.
151  if (len > cur_path.capacity()) {
152    cur_path.reserve(len);
153    goto retry_cur_dir;
154  }
155
156  cur_path.set_size(len);
157  // cur_path now holds the current directory in utf-16. Convert to utf-8.
158
159  // Find out how much space we need. Sadly, this function doesn't return the
160  // size needed unless you tell it the result size is 0, which means you
161  // _always_ have to call it twice.
162  len = ::WideCharToMultiByte(CP_UTF8, 0,
163                              cur_path.data(), cur_path.size(),
164                              result.data(), 0,
165                              NULL, NULL);
166
167  if (len == 0)
168    return make_error_code(windows_error(::GetLastError()));
169
170  result.reserve(len);
171  result.set_size(len);
172  // Now do the actual conversion.
173  len = ::WideCharToMultiByte(CP_UTF8, 0,
174                              cur_path.data(), cur_path.size(),
175                              result.data(), result.size(),
176                              NULL, NULL);
177  if (len == 0)
178    return windows_error(::GetLastError());
179
180  return success;
181}
182
183error_code copy_file(const Twine &from, const Twine &to, copy_option copt) {
184  // Get arguments.
185  SmallString<128> from_storage;
186  SmallString<128> to_storage;
187  StringRef f = from.toStringRef(from_storage);
188  StringRef t = to.toStringRef(to_storage);
189
190  // Convert to utf-16.
191  SmallVector<wchar_t, 128> wide_from;
192  SmallVector<wchar_t, 128> wide_to;
193  if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
194  if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
195
196  // Copy the file.
197  BOOL res = ::CopyFileW(wide_from.begin(), wide_to.begin(),
198                         copt != copy_option::overwrite_if_exists);
199
200  if (res == 0)
201    return windows_error(::GetLastError());
202
203  return success;
204}
205
206error_code create_directory(const Twine &path, bool &existed) {
207  SmallString<128> path_storage;
208  SmallVector<wchar_t, 128> path_utf16;
209
210  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
211                                  path_utf16))
212    return ec;
213
214  if (!::CreateDirectoryW(path_utf16.begin(), NULL)) {
215    error_code ec = windows_error(::GetLastError());
216    if (ec == windows_error::already_exists)
217      existed = true;
218    else
219      return ec;
220  } else
221    existed = false;
222
223  return success;
224}
225
226error_code create_hard_link(const Twine &to, const Twine &from) {
227  // Get arguments.
228  SmallString<128> from_storage;
229  SmallString<128> to_storage;
230  StringRef f = from.toStringRef(from_storage);
231  StringRef t = to.toStringRef(to_storage);
232
233  // Convert to utf-16.
234  SmallVector<wchar_t, 128> wide_from;
235  SmallVector<wchar_t, 128> wide_to;
236  if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
237  if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
238
239  if (!::CreateHardLinkW(wide_from.begin(), wide_to.begin(), NULL))
240    return windows_error(::GetLastError());
241
242  return success;
243}
244
245error_code create_symlink(const Twine &to, const Twine &from) {
246  // Only do it if the function is available at runtime.
247  if (!create_symbolic_link_api)
248    return make_error_code(errc::function_not_supported);
249
250  // Get arguments.
251  SmallString<128> from_storage;
252  SmallString<128> to_storage;
253  StringRef f = from.toStringRef(from_storage);
254  StringRef t = to.toStringRef(to_storage);
255
256  // Convert to utf-16.
257  SmallVector<wchar_t, 128> wide_from;
258  SmallVector<wchar_t, 128> wide_to;
259  if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
260  if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
261
262  if (!create_symbolic_link_api(wide_from.begin(), wide_to.begin(), 0))
263    return windows_error(::GetLastError());
264
265  return success;
266}
267
268error_code remove(const Twine &path, bool &existed) {
269  SmallString<128> path_storage;
270  SmallVector<wchar_t, 128> path_utf16;
271
272  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
273                                  path_utf16))
274    return ec;
275
276  if (!::DeleteFileW(path_utf16.begin())) {
277    error_code ec = windows_error(::GetLastError());
278    if (ec != windows_error::file_not_found)
279      return ec;
280    existed = false;
281  } else
282    existed = true;
283
284  return success;
285}
286
287error_code rename(const Twine &from, const Twine &to) {
288  // Get arguments.
289  SmallString<128> from_storage;
290  SmallString<128> to_storage;
291  StringRef f = from.toStringRef(from_storage);
292  StringRef t = to.toStringRef(to_storage);
293
294  // Convert to utf-16.
295  SmallVector<wchar_t, 128> wide_from;
296  SmallVector<wchar_t, 128> wide_to;
297  if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
298  if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
299
300  if (!::MoveFileW(wide_from.begin(), wide_to.begin()))
301    return windows_error(::GetLastError());
302
303  return success;
304}
305
306error_code resize_file(const Twine &path, uint64_t size) {
307  SmallString<128> path_storage;
308  SmallVector<wchar_t, 128> path_utf16;
309
310  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
311                                  path_utf16))
312    return ec;
313
314  int fd = ::_wopen(path_utf16.begin(), O_BINARY, S_IREAD | S_IWRITE);
315  if (fd == -1)
316    return error_code(errno, generic_category());
317#ifdef HAVE__CHSIZE_S
318  errno_t error = ::_chsize_s(fd, size);
319#else
320  errno_t error = ::_chsize(fd, size);
321#endif
322  ::close(fd);
323  return error_code(error, generic_category());
324}
325
326error_code exists(const Twine &path, bool &result) {
327  SmallString<128> path_storage;
328  SmallVector<wchar_t, 128> path_utf16;
329
330  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
331                                  path_utf16))
332    return ec;
333
334  DWORD attributes = ::GetFileAttributesW(path_utf16.begin());
335
336  if (attributes == INVALID_FILE_ATTRIBUTES) {
337    // See if the file didn't actually exist.
338    error_code ec = make_error_code(windows_error(::GetLastError()));
339    if (ec != windows_error::file_not_found &&
340        ec != windows_error::path_not_found)
341      return ec;
342    result = false;
343  } else
344    result = true;
345  return success;
346}
347
348error_code equivalent(const Twine &A, const Twine &B, bool &result) {
349  // Get arguments.
350  SmallString<128> a_storage;
351  SmallString<128> b_storage;
352  StringRef a = A.toStringRef(a_storage);
353  StringRef b = B.toStringRef(b_storage);
354
355  // Convert to utf-16.
356  SmallVector<wchar_t, 128> wide_a;
357  SmallVector<wchar_t, 128> wide_b;
358  if (error_code ec = UTF8ToUTF16(a, wide_a)) return ec;
359  if (error_code ec = UTF8ToUTF16(b, wide_b)) return ec;
360
361  AutoHandle HandleB(
362    ::CreateFileW(wide_b.begin(),
363                  0,
364                  FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
365                  0,
366                  OPEN_EXISTING,
367                  FILE_FLAG_BACKUP_SEMANTICS,
368                  0));
369
370  AutoHandle HandleA(
371    ::CreateFileW(wide_a.begin(),
372                  0,
373                  FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
374                  0,
375                  OPEN_EXISTING,
376                  FILE_FLAG_BACKUP_SEMANTICS,
377                  0));
378
379  // If both handles are invalid, it's an error.
380  if (HandleA == INVALID_HANDLE_VALUE &&
381      HandleB == INVALID_HANDLE_VALUE)
382    return windows_error(::GetLastError());
383
384  // If only one is invalid, it's false.
385  if (HandleA == INVALID_HANDLE_VALUE &&
386      HandleB == INVALID_HANDLE_VALUE) {
387    result = false;
388    return success;
389  }
390
391  // Get file information.
392  BY_HANDLE_FILE_INFORMATION InfoA, InfoB;
393  if (!::GetFileInformationByHandle(HandleA, &InfoA))
394    return windows_error(::GetLastError());
395  if (!::GetFileInformationByHandle(HandleB, &InfoB))
396    return windows_error(::GetLastError());
397
398  // See if it's all the same.
399  result =
400    InfoA.dwVolumeSerialNumber           == InfoB.dwVolumeSerialNumber &&
401    InfoA.nFileIndexHigh                 == InfoB.nFileIndexHigh &&
402    InfoA.nFileIndexLow                  == InfoB.nFileIndexLow &&
403    InfoA.nFileSizeHigh                  == InfoB.nFileSizeHigh &&
404    InfoA.nFileSizeLow                   == InfoB.nFileSizeLow &&
405    InfoA.ftLastWriteTime.dwLowDateTime  ==
406      InfoB.ftLastWriteTime.dwLowDateTime &&
407    InfoA.ftLastWriteTime.dwHighDateTime ==
408      InfoB.ftLastWriteTime.dwHighDateTime;
409
410  return success;
411}
412
413error_code file_size(const Twine &path, uint64_t &result) {
414  SmallString<128> path_storage;
415  SmallVector<wchar_t, 128> path_utf16;
416
417  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
418                                  path_utf16))
419    return ec;
420
421  WIN32_FILE_ATTRIBUTE_DATA FileData;
422  if (!::GetFileAttributesExW(path_utf16.begin(),
423                              ::GetFileExInfoStandard,
424                              &FileData))
425    return windows_error(::GetLastError());
426
427  result =
428    (uint64_t(FileData.nFileSizeHigh) << (sizeof(FileData.nFileSizeLow) * 8))
429    + FileData.nFileSizeLow;
430
431  return success;
432}
433
434error_code status(const Twine &path, file_status &result) {
435  SmallString<128> path_storage;
436  SmallVector<wchar_t, 128> path_utf16;
437
438  if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
439                                  path_utf16))
440    return ec;
441
442  DWORD attr = ::GetFileAttributesW(path_utf16.begin());
443  if (attr == INVALID_FILE_ATTRIBUTES)
444    goto handle_status_error;
445
446  // Handle reparse points.
447  if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
448    AutoHandle h(
449      ::CreateFileW(path_utf16.begin(),
450                    0, // Attributes only.
451                    FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
452                    NULL,
453                    OPEN_EXISTING,
454                    FILE_FLAG_BACKUP_SEMANTICS,
455                    0));
456    if (h == INVALID_HANDLE_VALUE)
457      goto handle_status_error;
458  }
459
460  if (attr & FILE_ATTRIBUTE_DIRECTORY)
461    result = file_status(file_type::directory_file);
462  else
463    result = file_status(file_type::regular_file);
464
465  return success;
466
467handle_status_error:
468  error_code ec = windows_error(::GetLastError());
469  if (ec == windows_error::file_not_found ||
470      ec == windows_error::path_not_found)
471    result = file_status(file_type::file_not_found);
472  else if (ec == windows_error::sharing_violation)
473    result = file_status(file_type::type_unknown);
474  else {
475    result = file_status(file_type::status_error);
476    return ec;
477  }
478
479  return success;
480}
481
482error_code unique_file(const Twine &model, int &result_fd,
483                             SmallVectorImpl<char> &result_path) {
484  // Use result_path as temp storage.
485  result_path.set_size(0);
486  StringRef m = model.toStringRef(result_path);
487
488  SmallVector<wchar_t, 128> model_utf16;
489  if (error_code ec = UTF8ToUTF16(m, model_utf16)) return ec;
490
491  // Make model absolute by prepending a temp directory if it's not already.
492  bool absolute = path::is_absolute(m);
493
494  if (!absolute) {
495    SmallVector<wchar_t, 64> temp_dir;
496    if (error_code ec = TempDir(temp_dir)) return ec;
497    // Handle c: by removing it.
498    if (model_utf16.size() > 2 && model_utf16[1] == L':') {
499      model_utf16.erase(model_utf16.begin(), model_utf16.begin() + 2);
500    }
501    model_utf16.insert(model_utf16.begin(), temp_dir.begin(), temp_dir.end());
502  }
503
504  // Replace '%' with random chars. From here on, DO NOT modify model. It may be
505  // needed if the randomly chosen path already exists.
506  SmallVector<wchar_t, 128> random_path_utf16;
507
508  // Get a Crypto Provider for CryptGenRandom.
509  HCRYPTPROV HCPC;
510  if (!::CryptAcquireContextW(&HCPC,
511                              NULL,
512                              NULL,
513                              PROV_RSA_FULL,
514                              0))
515    return windows_error(::GetLastError());
516  ScopedCryptContext CryptoProvider(HCPC);
517
518retry_random_path:
519  random_path_utf16.set_size(0);
520  for (SmallVectorImpl<wchar_t>::const_iterator i = model_utf16.begin(),
521                                                e = model_utf16.end();
522                                                i != e; ++i) {
523    if (*i == L'%') {
524      BYTE val = 0;
525      if (!::CryptGenRandom(CryptoProvider, 1, &val))
526          return windows_error(::GetLastError());
527      random_path_utf16.push_back("0123456789abcdef"[val & 15]);
528    }
529    else
530      random_path_utf16.push_back(*i);
531  }
532  // Make random_path_utf16 null terminated.
533  random_path_utf16.push_back(0);
534  random_path_utf16.pop_back();
535
536  // Try to create + open the path.
537retry_create_file:
538  HANDLE TempFileHandle = ::CreateFileW(random_path_utf16.begin(),
539                                        GENERIC_READ | GENERIC_WRITE,
540                                        FILE_SHARE_READ,
541                                        NULL,
542                                        // Return ERROR_FILE_EXISTS if the file
543                                        // already exists.
544                                        CREATE_NEW,
545                                        FILE_ATTRIBUTE_TEMPORARY,
546                                        NULL);
547  if (TempFileHandle == INVALID_HANDLE_VALUE) {
548    // If the file existed, try again, otherwise, error.
549    error_code ec = windows_error(::GetLastError());
550    if (ec == windows_error::file_exists)
551      goto retry_random_path;
552    // Check for non-existing parent directories.
553    if (ec == windows_error::path_not_found) {
554      // Create the directories using result_path as temp storage.
555      if (error_code ec = UTF16ToUTF8(random_path_utf16.begin(),
556                                      random_path_utf16.size(), result_path))
557        return ec;
558      StringRef p(result_path.begin(), result_path.size());
559      SmallString<64> dir_to_create;
560      for (path::const_iterator i = path::begin(p),
561                                e = --path::end(p); i != e; ++i) {
562        path::append(dir_to_create, *i);
563        bool Exists;
564        if (error_code ec = exists(Twine(dir_to_create), Exists)) return ec;
565        if (!Exists) {
566          // If c: doesn't exist, bail.
567          if (i->endswith(":"))
568            return ec;
569
570          SmallVector<wchar_t, 64> dir_to_create_utf16;
571          if (error_code ec = UTF8ToUTF16(dir_to_create, dir_to_create_utf16))
572            return ec;
573
574          // Create the directory.
575          if (!::CreateDirectoryW(dir_to_create_utf16.begin(), NULL))
576            return windows_error(::GetLastError());
577        }
578      }
579      goto retry_create_file;
580    }
581    return ec;
582  }
583
584  // Set result_path to the utf-8 representation of the path.
585  if (error_code ec = UTF16ToUTF8(random_path_utf16.begin(),
586                                  random_path_utf16.size(), result_path)) {
587    ::CloseHandle(TempFileHandle);
588    ::DeleteFileW(random_path_utf16.begin());
589    return ec;
590  }
591
592  // Convert the Windows API file handle into a C-runtime handle.
593  int fd = ::_open_osfhandle(intptr_t(TempFileHandle), 0);
594  if (fd == -1) {
595    ::CloseHandle(TempFileHandle);
596    ::DeleteFileW(random_path_utf16.begin());
597    // MSDN doesn't say anything about _open_osfhandle setting errno or
598    // GetLastError(), so just return invalid_handle.
599    return windows_error::invalid_handle;
600  }
601
602  result_fd = fd;
603  return success;
604}
605
606error_code directory_iterator_construct(directory_iterator& it,
607                                        const StringRef &path) {
608  SmallVector<wchar_t, 128> path_utf16;
609
610  if (error_code ec = UTF8ToUTF16(path,
611                                  path_utf16))
612    return ec;
613
614  // Convert path to the format that Windows is happy with.
615  if (path_utf16.size() > 0 &&
616      !is_separator(path_utf16[path.size() - 1]) &&
617      path_utf16[path.size() - 1] != L':') {
618    path_utf16.push_back(L'\\');
619    path_utf16.push_back(L'*');
620  } else {
621    path_utf16.push_back(L'*');
622  }
623
624  //  Get the first directory entry.
625  WIN32_FIND_DATAW FirstFind;
626  ScopedFindHandle FindHandle(::FindFirstFileW(path_utf16.c_str(), &FirstFind));
627  if (!FindHandle)
628    return windows_error(::GetLastError());
629
630  // Construct the current directory entry.
631  SmallString<128> directory_entry_path_utf8;
632  if (error_code ec = UTF16ToUTF8(FirstFind.cFileName,
633                                  ::wcslen(FirstFind.cFileName),
634                                  directory_entry_path_utf8))
635    return ec;
636
637  it.IterationHandle = intptr_t(FindHandle.take());
638  it.CurrentEntry = directory_entry(path);
639  it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8));
640
641  return success;
642}
643
644error_code directory_iterator_destruct(directory_iterator& it) {
645  if (it.IterationHandle != 0)
646    // Closes the handle if it's valid.
647    ScopedFindHandle close(HANDLE(it.IterationHandle));
648  it.IterationHandle = 0;
649  it.CurrentEntry = directory_entry();
650  return success;
651}
652
653error_code directory_iterator_increment(directory_iterator& it) {
654  WIN32_FIND_DATAW FindData;
655  if (!::FindNextFileW(HANDLE(it.IterationHandle), &FindData)) {
656    error_code ec = windows_error(::GetLastError());
657    // Check for end.
658    if (ec == windows_error::no_more_files)
659      return directory_iterator_destruct(it);
660    return ec;
661  }
662
663  SmallString<128> directory_entry_path_utf8;
664  if (error_code ec = UTF16ToUTF8(FindData.cFileName,
665                                  ::wcslen(FindData.cFileName),
666                                  directory_entry_path_utf8))
667    return ec;
668
669  it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8));
670  return success;
671}
672
673} // end namespace fs
674} // end namespace sys
675} // end namespace llvm
676