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      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 "Windows.h"
     21 #include <fcntl.h>
     22 #include <io.h>
     23 #include <sys/stat.h>
     24 #include <sys/types.h>
     25 
     26 #undef max
     27 
     28 // MinGW doesn't define this.
     29 #ifndef _ERRNO_T_DEFINED
     30 #define _ERRNO_T_DEFINED
     31 typedef int errno_t;
     32 #endif
     33 
     34 #ifdef _MSC_VER
     35 # pragma comment(lib, "advapi32.lib")  // This provides CryptAcquireContextW.
     36 #endif
     37 
     38 using namespace llvm;
     39 
     40 namespace {
     41   typedef BOOLEAN (WINAPI *PtrCreateSymbolicLinkW)(
     42     /*__in*/ LPCWSTR lpSymlinkFileName,
     43     /*__in*/ LPCWSTR lpTargetFileName,
     44     /*__in*/ DWORD dwFlags);
     45 
     46   PtrCreateSymbolicLinkW create_symbolic_link_api = PtrCreateSymbolicLinkW(
     47     ::GetProcAddress(::GetModuleHandleA("kernel32.dll"),
     48                      "CreateSymbolicLinkW"));
     49 
     50   error_code UTF8ToUTF16(StringRef utf8, SmallVectorImpl<wchar_t> &utf16) {
     51     int len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
     52                                     utf8.begin(), utf8.size(),
     53                                     utf16.begin(), 0);
     54 
     55     if (len == 0)
     56       return windows_error(::GetLastError());
     57 
     58     utf16.reserve(len + 1);
     59     utf16.set_size(len);
     60 
     61     len = ::MultiByteToWideChar(CP_UTF8, MB_ERR_INVALID_CHARS,
     62                                     utf8.begin(), utf8.size(),
     63                                     utf16.begin(), utf16.size());
     64 
     65     if (len == 0)
     66       return windows_error(::GetLastError());
     67 
     68     // Make utf16 null terminated.
     69     utf16.push_back(0);
     70     utf16.pop_back();
     71 
     72     return error_code::success();
     73   }
     74 
     75   error_code UTF16ToUTF8(const wchar_t *utf16, size_t utf16_len,
     76                                SmallVectorImpl<char> &utf8) {
     77     // Get length.
     78     int len = ::WideCharToMultiByte(CP_UTF8, 0,
     79                                     utf16, utf16_len,
     80                                     utf8.begin(), 0,
     81                                     NULL, NULL);
     82 
     83     if (len == 0)
     84       return windows_error(::GetLastError());
     85 
     86     utf8.reserve(len);
     87     utf8.set_size(len);
     88 
     89     // Now do the actual conversion.
     90     len = ::WideCharToMultiByte(CP_UTF8, 0,
     91                                 utf16, utf16_len,
     92                                 utf8.data(), utf8.size(),
     93                                 NULL, NULL);
     94 
     95     if (len == 0)
     96       return windows_error(::GetLastError());
     97 
     98     // Make utf8 null terminated.
     99     utf8.push_back(0);
    100     utf8.pop_back();
    101 
    102     return error_code::success();
    103   }
    104 
    105   error_code TempDir(SmallVectorImpl<wchar_t> &result) {
    106   retry_temp_dir:
    107     DWORD len = ::GetTempPathW(result.capacity(), result.begin());
    108 
    109     if (len == 0)
    110       return windows_error(::GetLastError());
    111 
    112     if (len > result.capacity()) {
    113       result.reserve(len);
    114       goto retry_temp_dir;
    115     }
    116 
    117     result.set_size(len);
    118     return error_code::success();
    119   }
    120 
    121   bool is_separator(const wchar_t value) {
    122     switch (value) {
    123     case L'\\':
    124     case L'/':
    125       return true;
    126     default:
    127       return false;
    128     }
    129   }
    130 }
    131 
    132 // FIXME: mode should be used here and default to user r/w only,
    133 // it currently comes in as a UNIX mode.
    134 static error_code createUniqueEntity(const Twine &model, int &result_fd,
    135                                      SmallVectorImpl<char> &result_path,
    136                                      bool makeAbsolute, unsigned mode,
    137                                      FSEntity Type) {
    138   // Use result_path as temp storage.
    139   result_path.set_size(0);
    140   StringRef m = model.toStringRef(result_path);
    141 
    142   SmallVector<wchar_t, 128> model_utf16;
    143   if (error_code ec = UTF8ToUTF16(m, model_utf16)) return ec;
    144 
    145   if (makeAbsolute) {
    146     // Make model absolute by prepending a temp directory if it's not already.
    147     bool absolute = sys::path::is_absolute(m);
    148 
    149     if (!absolute) {
    150       SmallVector<wchar_t, 64> temp_dir;
    151       if (error_code ec = TempDir(temp_dir)) return ec;
    152       // Handle c: by removing it.
    153       if (model_utf16.size() > 2 && model_utf16[1] == L':') {
    154         model_utf16.erase(model_utf16.begin(), model_utf16.begin() + 2);
    155       }
    156       model_utf16.insert(model_utf16.begin(), temp_dir.begin(), temp_dir.end());
    157     }
    158   }
    159 
    160   // Replace '%' with random chars. From here on, DO NOT modify model. It may be
    161   // needed if the randomly chosen path already exists.
    162   SmallVector<wchar_t, 128> random_path_utf16;
    163 
    164   // Get a Crypto Provider for CryptGenRandom.
    165   HCRYPTPROV HCPC;
    166   if (!::CryptAcquireContextW(&HCPC,
    167                               NULL,
    168                               NULL,
    169                               PROV_RSA_FULL,
    170                               CRYPT_VERIFYCONTEXT))
    171     return windows_error(::GetLastError());
    172   ScopedCryptContext CryptoProvider(HCPC);
    173 
    174 retry_random_path:
    175   random_path_utf16.set_size(0);
    176   for (SmallVectorImpl<wchar_t>::const_iterator i = model_utf16.begin(),
    177                                                 e = model_utf16.end();
    178                                                 i != e; ++i) {
    179     if (*i == L'%') {
    180       BYTE val = 0;
    181       if (!::CryptGenRandom(CryptoProvider, 1, &val))
    182           return windows_error(::GetLastError());
    183       random_path_utf16.push_back("0123456789abcdef"[val & 15]);
    184     }
    185     else
    186       random_path_utf16.push_back(*i);
    187   }
    188   // Make random_path_utf16 null terminated.
    189   random_path_utf16.push_back(0);
    190   random_path_utf16.pop_back();
    191 
    192   HANDLE TempFileHandle = INVALID_HANDLE_VALUE;
    193 
    194   switch (Type) {
    195   case FS_File: {
    196     // Try to create + open the path.
    197     TempFileHandle =
    198         ::CreateFileW(random_path_utf16.begin(), GENERIC_READ | GENERIC_WRITE,
    199                       FILE_SHARE_READ, NULL,
    200                       // Return ERROR_FILE_EXISTS if the file
    201                       // already exists.
    202                       CREATE_NEW, FILE_ATTRIBUTE_TEMPORARY, NULL);
    203     if (TempFileHandle == INVALID_HANDLE_VALUE) {
    204       // If the file existed, try again, otherwise, error.
    205       error_code ec = windows_error(::GetLastError());
    206       if (ec == windows_error::file_exists)
    207         goto retry_random_path;
    208 
    209       return ec;
    210     }
    211 
    212     // Convert the Windows API file handle into a C-runtime handle.
    213     int fd = ::_open_osfhandle(intptr_t(TempFileHandle), 0);
    214     if (fd == -1) {
    215       ::CloseHandle(TempFileHandle);
    216       ::DeleteFileW(random_path_utf16.begin());
    217       // MSDN doesn't say anything about _open_osfhandle setting errno or
    218       // GetLastError(), so just return invalid_handle.
    219       return windows_error::invalid_handle;
    220     }
    221 
    222     result_fd = fd;
    223     break;
    224   }
    225 
    226   case FS_Name: {
    227     DWORD attributes = ::GetFileAttributesW(random_path_utf16.begin());
    228     if (attributes != INVALID_FILE_ATTRIBUTES)
    229       goto retry_random_path;
    230     error_code EC = make_error_code(windows_error(::GetLastError()));
    231     if (EC != windows_error::file_not_found &&
    232         EC != windows_error::path_not_found)
    233       return EC;
    234     break;
    235   }
    236 
    237   case FS_Dir:
    238     if (!::CreateDirectoryW(random_path_utf16.begin(), NULL)) {
    239       error_code EC = windows_error(::GetLastError());
    240       if (EC != windows_error::already_exists)
    241         return EC;
    242       goto retry_random_path;
    243     }
    244     break;
    245   }
    246 
    247   // Set result_path to the utf-8 representation of the path.
    248   if (error_code ec = UTF16ToUTF8(random_path_utf16.begin(),
    249                                   random_path_utf16.size(), result_path)) {
    250     switch (Type) {
    251     case FS_File:
    252       ::CloseHandle(TempFileHandle);
    253       ::DeleteFileW(random_path_utf16.begin());
    254     case FS_Name:
    255       break;
    256     case FS_Dir:
    257       ::RemoveDirectoryW(random_path_utf16.begin());
    258       break;
    259     }
    260     return ec;
    261   }
    262 
    263   return error_code::success();
    264 }
    265 
    266 namespace llvm {
    267 namespace sys  {
    268 namespace fs {
    269 
    270 std::string getMainExecutable(const char *argv0, void *MainExecAddr) {
    271   char pathname[MAX_PATH];
    272   DWORD ret = ::GetModuleFileNameA(NULL, pathname, MAX_PATH);
    273   return ret != MAX_PATH ? pathname : "";
    274 }
    275 
    276 UniqueID file_status::getUniqueID() const {
    277   // The file is uniquely identified by the volume serial number along
    278   // with the 64-bit file identifier.
    279   uint64_t FileID = (static_cast<uint64_t>(FileIndexHigh) << 32ULL) |
    280                     static_cast<uint64_t>(FileIndexLow);
    281 
    282   return UniqueID(VolumeSerialNumber, FileID);
    283 }
    284 
    285 TimeValue file_status::getLastModificationTime() const {
    286   ULARGE_INTEGER UI;
    287   UI.LowPart = LastWriteTimeLow;
    288   UI.HighPart = LastWriteTimeHigh;
    289 
    290   TimeValue Ret;
    291   Ret.fromWin32Time(UI.QuadPart);
    292   return Ret;
    293 }
    294 
    295 error_code current_path(SmallVectorImpl<char> &result) {
    296   SmallVector<wchar_t, 128> cur_path;
    297   cur_path.reserve(128);
    298 retry_cur_dir:
    299   DWORD len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
    300 
    301   // A zero return value indicates a failure other than insufficient space.
    302   if (len == 0)
    303     return windows_error(::GetLastError());
    304 
    305   // If there's insufficient space, the len returned is larger than the len
    306   // given.
    307   if (len > cur_path.capacity()) {
    308     cur_path.reserve(len);
    309     goto retry_cur_dir;
    310   }
    311 
    312   cur_path.set_size(len);
    313   // cur_path now holds the current directory in utf-16. Convert to utf-8.
    314 
    315   // Find out how much space we need. Sadly, this function doesn't return the
    316   // size needed unless you tell it the result size is 0, which means you
    317   // _always_ have to call it twice.
    318   len = ::WideCharToMultiByte(CP_UTF8, 0,
    319                               cur_path.data(), cur_path.size(),
    320                               result.data(), 0,
    321                               NULL, NULL);
    322 
    323   if (len == 0)
    324     return make_error_code(windows_error(::GetLastError()));
    325 
    326   result.reserve(len);
    327   result.set_size(len);
    328   // Now do the actual conversion.
    329   len = ::WideCharToMultiByte(CP_UTF8, 0,
    330                               cur_path.data(), cur_path.size(),
    331                               result.data(), result.size(),
    332                               NULL, NULL);
    333   if (len == 0)
    334     return windows_error(::GetLastError());
    335 
    336   return error_code::success();
    337 }
    338 
    339 error_code create_directory(const Twine &path, bool &existed) {
    340   SmallString<128> path_storage;
    341   SmallVector<wchar_t, 128> path_utf16;
    342 
    343   if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
    344                                   path_utf16))
    345     return ec;
    346 
    347   if (!::CreateDirectoryW(path_utf16.begin(), NULL)) {
    348     error_code ec = windows_error(::GetLastError());
    349     if (ec == windows_error::already_exists)
    350       existed = true;
    351     else
    352       return ec;
    353   } else
    354     existed = false;
    355 
    356   return error_code::success();
    357 }
    358 
    359 error_code create_hard_link(const Twine &to, const Twine &from) {
    360   // Get arguments.
    361   SmallString<128> from_storage;
    362   SmallString<128> to_storage;
    363   StringRef f = from.toStringRef(from_storage);
    364   StringRef t = to.toStringRef(to_storage);
    365 
    366   // Convert to utf-16.
    367   SmallVector<wchar_t, 128> wide_from;
    368   SmallVector<wchar_t, 128> wide_to;
    369   if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
    370   if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
    371 
    372   if (!::CreateHardLinkW(wide_from.begin(), wide_to.begin(), NULL))
    373     return windows_error(::GetLastError());
    374 
    375   return error_code::success();
    376 }
    377 
    378 error_code create_symlink(const Twine &to, const Twine &from) {
    379   // Only do it if the function is available at runtime.
    380   if (!create_symbolic_link_api)
    381     return make_error_code(errc::function_not_supported);
    382 
    383   // Get arguments.
    384   SmallString<128> from_storage;
    385   SmallString<128> to_storage;
    386   StringRef f = from.toStringRef(from_storage);
    387   StringRef t = to.toStringRef(to_storage);
    388 
    389   // Convert to utf-16.
    390   SmallVector<wchar_t, 128> wide_from;
    391   SmallVector<wchar_t, 128> wide_to;
    392   if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
    393   if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
    394 
    395   if (!create_symbolic_link_api(wide_from.begin(), wide_to.begin(), 0))
    396     return windows_error(::GetLastError());
    397 
    398   return error_code::success();
    399 }
    400 
    401 error_code remove(const Twine &path, bool &existed) {
    402   SmallString<128> path_storage;
    403   SmallVector<wchar_t, 128> path_utf16;
    404 
    405   file_status st;
    406   error_code EC = status(path, st);
    407   if (EC) {
    408     if (EC == windows_error::file_not_found ||
    409         EC == windows_error::path_not_found) {
    410       existed = false;
    411       return error_code::success();
    412     }
    413     return EC;
    414   }
    415 
    416   if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
    417                                   path_utf16))
    418     return ec;
    419 
    420   if (st.type() == file_type::directory_file) {
    421     if (!::RemoveDirectoryW(c_str(path_utf16))) {
    422       error_code ec = windows_error(::GetLastError());
    423       if (ec != windows_error::file_not_found)
    424         return ec;
    425       existed = false;
    426     } else
    427       existed = true;
    428   } else {
    429     if (!::DeleteFileW(c_str(path_utf16))) {
    430       error_code ec = windows_error(::GetLastError());
    431       if (ec != windows_error::file_not_found)
    432         return ec;
    433       existed = false;
    434     } else
    435       existed = true;
    436   }
    437 
    438   return error_code::success();
    439 }
    440 
    441 error_code rename(const Twine &from, const Twine &to) {
    442   // Get arguments.
    443   SmallString<128> from_storage;
    444   SmallString<128> to_storage;
    445   StringRef f = from.toStringRef(from_storage);
    446   StringRef t = to.toStringRef(to_storage);
    447 
    448   // Convert to utf-16.
    449   SmallVector<wchar_t, 128> wide_from;
    450   SmallVector<wchar_t, 128> wide_to;
    451   if (error_code ec = UTF8ToUTF16(f, wide_from)) return ec;
    452   if (error_code ec = UTF8ToUTF16(t, wide_to)) return ec;
    453 
    454   error_code ec = error_code::success();
    455   for (int i = 0; i < 2000; i++) {
    456     if (::MoveFileExW(wide_from.begin(), wide_to.begin(),
    457                       MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING))
    458       return error_code::success();
    459     ec = windows_error(::GetLastError());
    460     if (ec != windows_error::access_denied)
    461       break;
    462     // Retry MoveFile() at ACCESS_DENIED.
    463     // System scanners (eg. indexer) might open the source file when
    464     // It is written and closed.
    465     ::Sleep(1);
    466   }
    467 
    468   return ec;
    469 }
    470 
    471 error_code resize_file(const Twine &path, uint64_t size) {
    472   SmallString<128> path_storage;
    473   SmallVector<wchar_t, 128> path_utf16;
    474 
    475   if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
    476                                   path_utf16))
    477     return ec;
    478 
    479   int fd = ::_wopen(path_utf16.begin(), O_BINARY | _O_RDWR, S_IWRITE);
    480   if (fd == -1)
    481     return error_code(errno, generic_category());
    482 #ifdef HAVE__CHSIZE_S
    483   errno_t error = ::_chsize_s(fd, size);
    484 #else
    485   errno_t error = ::_chsize(fd, size);
    486 #endif
    487   ::close(fd);
    488   return error_code(error, generic_category());
    489 }
    490 
    491 error_code exists(const Twine &path, bool &result) {
    492   SmallString<128> path_storage;
    493   SmallVector<wchar_t, 128> path_utf16;
    494 
    495   if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
    496                                   path_utf16))
    497     return ec;
    498 
    499   DWORD attributes = ::GetFileAttributesW(path_utf16.begin());
    500 
    501   if (attributes == INVALID_FILE_ATTRIBUTES) {
    502     // See if the file didn't actually exist.
    503     error_code ec = make_error_code(windows_error(::GetLastError()));
    504     if (ec != windows_error::file_not_found &&
    505         ec != windows_error::path_not_found)
    506       return ec;
    507     result = false;
    508   } else
    509     result = true;
    510   return error_code::success();
    511 }
    512 
    513 bool can_write(const Twine &Path) {
    514   // FIXME: take security attributes into account.
    515   SmallString<128> PathStorage;
    516   SmallVector<wchar_t, 128> PathUtf16;
    517 
    518   if (UTF8ToUTF16(Path.toStringRef(PathStorage), PathUtf16))
    519     return false;
    520 
    521   DWORD Attr = ::GetFileAttributesW(PathUtf16.begin());
    522   return (Attr != INVALID_FILE_ATTRIBUTES) && !(Attr & FILE_ATTRIBUTE_READONLY);
    523 }
    524 
    525 bool can_execute(const Twine &Path) {
    526   SmallString<128> PathStorage;
    527   SmallVector<wchar_t, 128> PathUtf16;
    528 
    529   if (UTF8ToUTF16(Path.toStringRef(PathStorage), PathUtf16))
    530     return false;
    531 
    532   DWORD Attr = ::GetFileAttributesW(PathUtf16.begin());
    533   return Attr != INVALID_FILE_ATTRIBUTES;
    534 }
    535 
    536 bool equivalent(file_status A, file_status B) {
    537   assert(status_known(A) && status_known(B));
    538   return A.FileIndexHigh      == B.FileIndexHigh &&
    539          A.FileIndexLow       == B.FileIndexLow &&
    540          A.FileSizeHigh       == B.FileSizeHigh &&
    541          A.FileSizeLow        == B.FileSizeLow &&
    542          A.LastWriteTimeHigh  == B.LastWriteTimeHigh &&
    543          A.LastWriteTimeLow   == B.LastWriteTimeLow &&
    544          A.VolumeSerialNumber == B.VolumeSerialNumber;
    545 }
    546 
    547 error_code equivalent(const Twine &A, const Twine &B, bool &result) {
    548   file_status fsA, fsB;
    549   if (error_code ec = status(A, fsA)) return ec;
    550   if (error_code ec = status(B, fsB)) return ec;
    551   result = equivalent(fsA, fsB);
    552   return error_code::success();
    553 }
    554 
    555 static bool isReservedName(StringRef path) {
    556   // This list of reserved names comes from MSDN, at:
    557   // http://msdn.microsoft.com/en-us/library/aa365247%28v=vs.85%29.aspx
    558   static const char *sReservedNames[] = { "nul", "con", "prn", "aux",
    559                               "com1", "com2", "com3", "com4", "com5", "com6",
    560                               "com7", "com8", "com9", "lpt1", "lpt2", "lpt3",
    561                               "lpt4", "lpt5", "lpt6", "lpt7", "lpt8", "lpt9" };
    562 
    563   // First, check to see if this is a device namespace, which always
    564   // starts with \\.\, since device namespaces are not legal file paths.
    565   if (path.startswith("\\\\.\\"))
    566     return true;
    567 
    568   // Then compare against the list of ancient reserved names
    569   for (size_t i = 0; i < array_lengthof(sReservedNames); ++i) {
    570     if (path.equals_lower(sReservedNames[i]))
    571       return true;
    572   }
    573 
    574   // The path isn't what we consider reserved.
    575   return false;
    576 }
    577 
    578 static error_code getStatus(HANDLE FileHandle, file_status &Result) {
    579   if (FileHandle == INVALID_HANDLE_VALUE)
    580     goto handle_status_error;
    581 
    582   switch (::GetFileType(FileHandle)) {
    583   default:
    584     llvm_unreachable("Don't know anything about this file type");
    585   case FILE_TYPE_UNKNOWN: {
    586     DWORD Err = ::GetLastError();
    587     if (Err != NO_ERROR)
    588       return windows_error(Err);
    589     Result = file_status(file_type::type_unknown);
    590     return error_code::success();
    591   }
    592   case FILE_TYPE_DISK:
    593     break;
    594   case FILE_TYPE_CHAR:
    595     Result = file_status(file_type::character_file);
    596     return error_code::success();
    597   case FILE_TYPE_PIPE:
    598     Result = file_status(file_type::fifo_file);
    599     return error_code::success();
    600   }
    601 
    602   BY_HANDLE_FILE_INFORMATION Info;
    603   if (!::GetFileInformationByHandle(FileHandle, &Info))
    604     goto handle_status_error;
    605 
    606   {
    607     file_type Type = (Info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
    608                          ? file_type::directory_file
    609                          : file_type::regular_file;
    610     Result =
    611         file_status(Type, Info.ftLastWriteTime.dwHighDateTime,
    612                     Info.ftLastWriteTime.dwLowDateTime,
    613                     Info.dwVolumeSerialNumber, Info.nFileSizeHigh,
    614                     Info.nFileSizeLow, Info.nFileIndexHigh, Info.nFileIndexLow);
    615     return error_code::success();
    616   }
    617 
    618 handle_status_error:
    619   error_code EC = windows_error(::GetLastError());
    620   if (EC == windows_error::file_not_found ||
    621       EC == windows_error::path_not_found)
    622     Result = file_status(file_type::file_not_found);
    623   else if (EC == windows_error::sharing_violation)
    624     Result = file_status(file_type::type_unknown);
    625   else
    626     Result = file_status(file_type::status_error);
    627   return EC;
    628 }
    629 
    630 error_code status(const Twine &path, file_status &result) {
    631   SmallString<128> path_storage;
    632   SmallVector<wchar_t, 128> path_utf16;
    633 
    634   StringRef path8 = path.toStringRef(path_storage);
    635   if (isReservedName(path8)) {
    636     result = file_status(file_type::character_file);
    637     return error_code::success();
    638   }
    639 
    640   if (error_code ec = UTF8ToUTF16(path8, path_utf16))
    641     return ec;
    642 
    643   DWORD attr = ::GetFileAttributesW(path_utf16.begin());
    644   if (attr == INVALID_FILE_ATTRIBUTES)
    645     return getStatus(INVALID_HANDLE_VALUE, result);
    646 
    647   // Handle reparse points.
    648   if (attr & FILE_ATTRIBUTE_REPARSE_POINT) {
    649     ScopedFileHandle h(
    650       ::CreateFileW(path_utf16.begin(),
    651                     0, // Attributes only.
    652                     FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
    653                     NULL,
    654                     OPEN_EXISTING,
    655                     FILE_FLAG_BACKUP_SEMANTICS,
    656                     0));
    657     if (!h)
    658       return getStatus(INVALID_HANDLE_VALUE, result);
    659   }
    660 
    661   ScopedFileHandle h(
    662       ::CreateFileW(path_utf16.begin(), 0, // Attributes only.
    663                     FILE_SHARE_DELETE | FILE_SHARE_READ | FILE_SHARE_WRITE,
    664                     NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, 0));
    665     if (!h)
    666       return getStatus(INVALID_HANDLE_VALUE, result);
    667 
    668     return getStatus(h, result);
    669 }
    670 
    671 error_code status(int FD, file_status &Result) {
    672   HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
    673   return getStatus(FileHandle, Result);
    674 }
    675 
    676 error_code setLastModificationAndAccessTime(int FD, TimeValue Time) {
    677   ULARGE_INTEGER UI;
    678   UI.QuadPart = Time.toWin32Time();
    679   FILETIME FT;
    680   FT.dwLowDateTime = UI.LowPart;
    681   FT.dwHighDateTime = UI.HighPart;
    682   HANDLE FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
    683   if (!SetFileTime(FileHandle, NULL, &FT, &FT))
    684     return windows_error(::GetLastError());
    685   return error_code::success();
    686 }
    687 
    688 error_code get_magic(const Twine &path, uint32_t len,
    689                      SmallVectorImpl<char> &result) {
    690   SmallString<128> path_storage;
    691   SmallVector<wchar_t, 128> path_utf16;
    692   result.set_size(0);
    693 
    694   // Convert path to UTF-16.
    695   if (error_code ec = UTF8ToUTF16(path.toStringRef(path_storage),
    696                                   path_utf16))
    697     return ec;
    698 
    699   // Open file.
    700   HANDLE file = ::CreateFileW(c_str(path_utf16),
    701                               GENERIC_READ,
    702                               FILE_SHARE_READ,
    703                               NULL,
    704                               OPEN_EXISTING,
    705                               FILE_ATTRIBUTE_READONLY,
    706                               NULL);
    707   if (file == INVALID_HANDLE_VALUE)
    708     return windows_error(::GetLastError());
    709 
    710   // Allocate buffer.
    711   result.reserve(len);
    712 
    713   // Get magic!
    714   DWORD bytes_read = 0;
    715   BOOL read_success = ::ReadFile(file, result.data(), len, &bytes_read, NULL);
    716   error_code ec = windows_error(::GetLastError());
    717   ::CloseHandle(file);
    718   if (!read_success || (bytes_read != len)) {
    719     // Set result size to the number of bytes read if it's valid.
    720     if (bytes_read <= len)
    721       result.set_size(bytes_read);
    722     // ERROR_HANDLE_EOF is mapped to errc::value_too_large.
    723     return ec;
    724   }
    725 
    726   result.set_size(len);
    727   return error_code::success();
    728 }
    729 
    730 error_code mapped_file_region::init(int FD, bool CloseFD, uint64_t Offset) {
    731   FileDescriptor = FD;
    732   // Make sure that the requested size fits within SIZE_T.
    733   if (Size > std::numeric_limits<SIZE_T>::max()) {
    734     if (FileDescriptor) {
    735       if (CloseFD)
    736         _close(FileDescriptor);
    737     } else
    738       ::CloseHandle(FileHandle);
    739     return make_error_code(errc::invalid_argument);
    740   }
    741 
    742   DWORD flprotect;
    743   switch (Mode) {
    744   case readonly:  flprotect = PAGE_READONLY; break;
    745   case readwrite: flprotect = PAGE_READWRITE; break;
    746   case priv:      flprotect = PAGE_WRITECOPY; break;
    747   }
    748 
    749   FileMappingHandle = ::CreateFileMapping(FileHandle,
    750                                           0,
    751                                           flprotect,
    752                                           Size >> 32,
    753                                           Size & 0xffffffff,
    754                                           0);
    755   if (FileMappingHandle == NULL) {
    756     error_code ec = windows_error(GetLastError());
    757     if (FileDescriptor) {
    758       if (CloseFD)
    759         _close(FileDescriptor);
    760     } else
    761       ::CloseHandle(FileHandle);
    762     return ec;
    763   }
    764 
    765   DWORD dwDesiredAccess;
    766   switch (Mode) {
    767   case readonly:  dwDesiredAccess = FILE_MAP_READ; break;
    768   case readwrite: dwDesiredAccess = FILE_MAP_WRITE; break;
    769   case priv:      dwDesiredAccess = FILE_MAP_COPY; break;
    770   }
    771   Mapping = ::MapViewOfFile(FileMappingHandle,
    772                             dwDesiredAccess,
    773                             Offset >> 32,
    774                             Offset & 0xffffffff,
    775                             Size);
    776   if (Mapping == NULL) {
    777     error_code ec = windows_error(GetLastError());
    778     ::CloseHandle(FileMappingHandle);
    779     if (FileDescriptor) {
    780       if (CloseFD)
    781         _close(FileDescriptor);
    782     } else
    783       ::CloseHandle(FileHandle);
    784     return ec;
    785   }
    786 
    787   if (Size == 0) {
    788     MEMORY_BASIC_INFORMATION mbi;
    789     SIZE_T Result = VirtualQuery(Mapping, &mbi, sizeof(mbi));
    790     if (Result == 0) {
    791       error_code ec = windows_error(GetLastError());
    792       ::UnmapViewOfFile(Mapping);
    793       ::CloseHandle(FileMappingHandle);
    794       if (FileDescriptor) {
    795         if (CloseFD)
    796           _close(FileDescriptor);
    797       } else
    798         ::CloseHandle(FileHandle);
    799       return ec;
    800     }
    801     Size = mbi.RegionSize;
    802   }
    803 
    804   // Close all the handles except for the view. It will keep the other handles
    805   // alive.
    806   ::CloseHandle(FileMappingHandle);
    807   if (FileDescriptor) {
    808     if (CloseFD)
    809       _close(FileDescriptor); // Also closes FileHandle.
    810   } else
    811     ::CloseHandle(FileHandle);
    812   return error_code::success();
    813 }
    814 
    815 mapped_file_region::mapped_file_region(const Twine &path,
    816                                        mapmode mode,
    817                                        uint64_t length,
    818                                        uint64_t offset,
    819                                        error_code &ec) 
    820   : Mode(mode)
    821   , Size(length)
    822   , Mapping()
    823   , FileDescriptor()
    824   , FileHandle(INVALID_HANDLE_VALUE)
    825   , FileMappingHandle() {
    826   SmallString<128> path_storage;
    827   SmallVector<wchar_t, 128> path_utf16;
    828 
    829   // Convert path to UTF-16.
    830   if ((ec = UTF8ToUTF16(path.toStringRef(path_storage), path_utf16)))
    831     return;
    832 
    833   // Get file handle for creating a file mapping.
    834   FileHandle = ::CreateFileW(c_str(path_utf16),
    835                              Mode == readonly ? GENERIC_READ
    836                                               : GENERIC_READ | GENERIC_WRITE,
    837                              Mode == readonly ? FILE_SHARE_READ
    838                                               : 0,
    839                              0,
    840                              Mode == readonly ? OPEN_EXISTING
    841                                               : OPEN_ALWAYS,
    842                              Mode == readonly ? FILE_ATTRIBUTE_READONLY
    843                                               : FILE_ATTRIBUTE_NORMAL,
    844                              0);
    845   if (FileHandle == INVALID_HANDLE_VALUE) {
    846     ec = windows_error(::GetLastError());
    847     return;
    848   }
    849 
    850   FileDescriptor = 0;
    851   ec = init(FileDescriptor, true, offset);
    852   if (ec) {
    853     Mapping = FileMappingHandle = 0;
    854     FileHandle = INVALID_HANDLE_VALUE;
    855     FileDescriptor = 0;
    856   }
    857 }
    858 
    859 mapped_file_region::mapped_file_region(int fd,
    860                                        bool closefd,
    861                                        mapmode mode,
    862                                        uint64_t length,
    863                                        uint64_t offset,
    864                                        error_code &ec)
    865   : Mode(mode)
    866   , Size(length)
    867   , Mapping()
    868   , FileDescriptor(fd)
    869   , FileHandle(INVALID_HANDLE_VALUE)
    870   , FileMappingHandle() {
    871   FileHandle = reinterpret_cast<HANDLE>(_get_osfhandle(fd));
    872   if (FileHandle == INVALID_HANDLE_VALUE) {
    873     if (closefd)
    874       _close(FileDescriptor);
    875     FileDescriptor = 0;
    876     ec = make_error_code(errc::bad_file_descriptor);
    877     return;
    878   }
    879 
    880   ec = init(FileDescriptor, closefd, offset);
    881   if (ec) {
    882     Mapping = FileMappingHandle = 0;
    883     FileHandle = INVALID_HANDLE_VALUE;
    884     FileDescriptor = 0;
    885   }
    886 }
    887 
    888 mapped_file_region::~mapped_file_region() {
    889   if (Mapping)
    890     ::UnmapViewOfFile(Mapping);
    891 }
    892 
    893 #if LLVM_HAS_RVALUE_REFERENCES
    894 mapped_file_region::mapped_file_region(mapped_file_region &&other)
    895   : Mode(other.Mode)
    896   , Size(other.Size)
    897   , Mapping(other.Mapping)
    898   , FileDescriptor(other.FileDescriptor)
    899   , FileHandle(other.FileHandle)
    900   , FileMappingHandle(other.FileMappingHandle) {
    901   other.Mapping = other.FileMappingHandle = 0;
    902   other.FileHandle = INVALID_HANDLE_VALUE;
    903   other.FileDescriptor = 0;
    904 }
    905 #endif
    906 
    907 mapped_file_region::mapmode mapped_file_region::flags() const {
    908   assert(Mapping && "Mapping failed but used anyway!");
    909   return Mode;
    910 }
    911 
    912 uint64_t mapped_file_region::size() const {
    913   assert(Mapping && "Mapping failed but used anyway!");
    914   return Size;
    915 }
    916 
    917 char *mapped_file_region::data() const {
    918   assert(Mode != readonly && "Cannot get non const data for readonly mapping!");
    919   assert(Mapping && "Mapping failed but used anyway!");
    920   return reinterpret_cast<char*>(Mapping);
    921 }
    922 
    923 const char *mapped_file_region::const_data() const {
    924   assert(Mapping && "Mapping failed but used anyway!");
    925   return reinterpret_cast<const char*>(Mapping);
    926 }
    927 
    928 int mapped_file_region::alignment() {
    929   SYSTEM_INFO SysInfo;
    930   ::GetSystemInfo(&SysInfo);
    931   return SysInfo.dwAllocationGranularity;
    932 }
    933 
    934 error_code detail::directory_iterator_construct(detail::DirIterState &it,
    935                                                 StringRef path){
    936   SmallVector<wchar_t, 128> path_utf16;
    937 
    938   if (error_code ec = UTF8ToUTF16(path,
    939                                   path_utf16))
    940     return ec;
    941 
    942   // Convert path to the format that Windows is happy with.
    943   if (path_utf16.size() > 0 &&
    944       !is_separator(path_utf16[path.size() - 1]) &&
    945       path_utf16[path.size() - 1] != L':') {
    946     path_utf16.push_back(L'\\');
    947     path_utf16.push_back(L'*');
    948   } else {
    949     path_utf16.push_back(L'*');
    950   }
    951 
    952   //  Get the first directory entry.
    953   WIN32_FIND_DATAW FirstFind;
    954   ScopedFindHandle FindHandle(::FindFirstFileW(c_str(path_utf16), &FirstFind));
    955   if (!FindHandle)
    956     return windows_error(::GetLastError());
    957 
    958   size_t FilenameLen = ::wcslen(FirstFind.cFileName);
    959   while ((FilenameLen == 1 && FirstFind.cFileName[0] == L'.') ||
    960          (FilenameLen == 2 && FirstFind.cFileName[0] == L'.' &&
    961                               FirstFind.cFileName[1] == L'.'))
    962     if (!::FindNextFileW(FindHandle, &FirstFind)) {
    963       error_code ec = windows_error(::GetLastError());
    964       // Check for end.
    965       if (ec == windows_error::no_more_files)
    966         return detail::directory_iterator_destruct(it);
    967       return ec;
    968     } else
    969       FilenameLen = ::wcslen(FirstFind.cFileName);
    970 
    971   // Construct the current directory entry.
    972   SmallString<128> directory_entry_name_utf8;
    973   if (error_code ec = UTF16ToUTF8(FirstFind.cFileName,
    974                                   ::wcslen(FirstFind.cFileName),
    975                                   directory_entry_name_utf8))
    976     return ec;
    977 
    978   it.IterationHandle = intptr_t(FindHandle.take());
    979   SmallString<128> directory_entry_path(path);
    980   path::append(directory_entry_path, directory_entry_name_utf8.str());
    981   it.CurrentEntry = directory_entry(directory_entry_path.str());
    982 
    983   return error_code::success();
    984 }
    985 
    986 error_code detail::directory_iterator_destruct(detail::DirIterState &it) {
    987   if (it.IterationHandle != 0)
    988     // Closes the handle if it's valid.
    989     ScopedFindHandle close(HANDLE(it.IterationHandle));
    990   it.IterationHandle = 0;
    991   it.CurrentEntry = directory_entry();
    992   return error_code::success();
    993 }
    994 
    995 error_code detail::directory_iterator_increment(detail::DirIterState &it) {
    996   WIN32_FIND_DATAW FindData;
    997   if (!::FindNextFileW(HANDLE(it.IterationHandle), &FindData)) {
    998     error_code ec = windows_error(::GetLastError());
    999     // Check for end.
   1000     if (ec == windows_error::no_more_files)
   1001       return detail::directory_iterator_destruct(it);
   1002     return ec;
   1003   }
   1004 
   1005   size_t FilenameLen = ::wcslen(FindData.cFileName);
   1006   if ((FilenameLen == 1 && FindData.cFileName[0] == L'.') ||
   1007       (FilenameLen == 2 && FindData.cFileName[0] == L'.' &&
   1008                            FindData.cFileName[1] == L'.'))
   1009     return directory_iterator_increment(it);
   1010 
   1011   SmallString<128> directory_entry_path_utf8;
   1012   if (error_code ec = UTF16ToUTF8(FindData.cFileName,
   1013                                   ::wcslen(FindData.cFileName),
   1014                                   directory_entry_path_utf8))
   1015     return ec;
   1016 
   1017   it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8));
   1018   return error_code::success();
   1019 }
   1020 
   1021 error_code map_file_pages(const Twine &path, off_t file_offset, size_t size,  
   1022                                             bool map_writable, void *&result) {
   1023   assert(0 && "NOT IMPLEMENTED");
   1024   return windows_error::invalid_function;
   1025 }
   1026 
   1027 error_code unmap_file_pages(void *base, size_t size) {
   1028   assert(0 && "NOT IMPLEMENTED");
   1029   return windows_error::invalid_function;
   1030 }
   1031 
   1032 error_code openFileForRead(const Twine &Name, int &ResultFD) {
   1033   SmallString<128> PathStorage;
   1034   SmallVector<wchar_t, 128> PathUTF16;
   1035 
   1036   if (error_code EC = UTF8ToUTF16(Name.toStringRef(PathStorage),
   1037                                   PathUTF16))
   1038     return EC;
   1039 
   1040   HANDLE H = ::CreateFileW(PathUTF16.begin(), GENERIC_READ,
   1041                            FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
   1042                            OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
   1043   if (H == INVALID_HANDLE_VALUE) {
   1044     error_code EC = windows_error(::GetLastError());
   1045     // Provide a better error message when trying to open directories.
   1046     // This only runs if we failed to open the file, so there is probably
   1047     // no performances issues.
   1048     if (EC != windows_error::access_denied)
   1049       return EC;
   1050     if (is_directory(Name))
   1051       return error_code(errc::is_a_directory, posix_category());
   1052     return EC;
   1053   }
   1054 
   1055   int FD = ::_open_osfhandle(intptr_t(H), 0);
   1056   if (FD == -1) {
   1057     ::CloseHandle(H);
   1058     return windows_error::invalid_handle;
   1059   }
   1060 
   1061   ResultFD = FD;
   1062   return error_code::success();
   1063 }
   1064 
   1065 error_code openFileForWrite(const Twine &Name, int &ResultFD,
   1066                             sys::fs::OpenFlags Flags, unsigned Mode) {
   1067   // Verify that we don't have both "append" and "excl".
   1068   assert((!(Flags & sys::fs::F_Excl) || !(Flags & sys::fs::F_Append)) &&
   1069          "Cannot specify both 'excl' and 'append' file creation flags!");
   1070 
   1071   SmallString<128> PathStorage;
   1072   SmallVector<wchar_t, 128> PathUTF16;
   1073 
   1074   if (error_code EC = UTF8ToUTF16(Name.toStringRef(PathStorage),
   1075                                   PathUTF16))
   1076     return EC;
   1077 
   1078   DWORD CreationDisposition;
   1079   if (Flags & F_Excl)
   1080     CreationDisposition = CREATE_NEW;
   1081   else if (Flags & F_Append) 
   1082     CreationDisposition = OPEN_ALWAYS;
   1083   else
   1084     CreationDisposition = CREATE_ALWAYS;
   1085 
   1086   HANDLE H = ::CreateFileW(PathUTF16.begin(), GENERIC_WRITE,
   1087                            FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
   1088                            CreationDisposition, FILE_ATTRIBUTE_NORMAL, NULL);
   1089 
   1090   if (H == INVALID_HANDLE_VALUE) {
   1091     error_code EC = windows_error(::GetLastError());
   1092     // Provide a better error message when trying to open directories.
   1093     // This only runs if we failed to open the file, so there is probably
   1094     // no performances issues.
   1095     if (EC != windows_error::access_denied)
   1096       return EC;
   1097     if (is_directory(Name))
   1098       return error_code(errc::is_a_directory, posix_category());
   1099     return EC;
   1100   }
   1101 
   1102   int OpenFlags = 0;
   1103   if (Flags & F_Append)
   1104     OpenFlags |= _O_APPEND;
   1105 
   1106   if (!(Flags & F_Binary))
   1107     OpenFlags |= _O_TEXT;
   1108 
   1109   int FD = ::_open_osfhandle(intptr_t(H), OpenFlags);
   1110   if (FD == -1) {
   1111     ::CloseHandle(H);
   1112     return windows_error::invalid_handle;
   1113   }
   1114 
   1115   ResultFD = FD;
   1116   return error_code::success();
   1117 }
   1118 
   1119 } // end namespace fs
   1120 } // end namespace sys
   1121 } // end namespace llvm
   1122