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      1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include "base/file_util.h"
      6 
      7 #include <windows.h>
      8 #include <propvarutil.h>
      9 #include <psapi.h>
     10 #include <shellapi.h>
     11 #include <shlobj.h>
     12 #include <time.h>
     13 #include <string>
     14 
     15 #include "base/file_path.h"
     16 #include "base/logging.h"
     17 #include "base/metrics/histogram.h"
     18 #include "base/win/pe_image.h"
     19 #include "base/win/scoped_handle.h"
     20 #include "base/string_number_conversions.h"
     21 #include "base/string_util.h"
     22 #include "base/threading/thread_restrictions.h"
     23 #include "base/time.h"
     24 #include "base/utf_string_conversions.h"
     25 #include "base/win/scoped_comptr.h"
     26 #include "base/win/win_util.h"
     27 #include "base/win/windows_version.h"
     28 
     29 namespace file_util {
     30 
     31 namespace {
     32 
     33 const DWORD kFileShareAll =
     34     FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
     35 
     36 // Helper for NormalizeFilePath(), defined below.
     37 bool DevicePathToDriveLetterPath(const FilePath& device_path,
     38                                  FilePath* drive_letter_path) {
     39   base::ThreadRestrictions::AssertIOAllowed();
     40 
     41   // Get the mapping of drive letters to device paths.
     42   const int kDriveMappingSize = 1024;
     43   wchar_t drive_mapping[kDriveMappingSize] = {'\0'};
     44   if (!::GetLogicalDriveStrings(kDriveMappingSize - 1, drive_mapping)) {
     45     LOG(ERROR) << "Failed to get drive mapping.";
     46     return false;
     47   }
     48 
     49   // The drive mapping is a sequence of null terminated strings.
     50   // The last string is empty.
     51   wchar_t* drive_map_ptr = drive_mapping;
     52   wchar_t device_name[MAX_PATH];
     53   wchar_t drive[] = L" :";
     54 
     55   // For each string in the drive mapping, get the junction that links
     56   // to it.  If that junction is a prefix of |device_path|, then we
     57   // know that |drive| is the real path prefix.
     58   while (*drive_map_ptr) {
     59     drive[0] = drive_map_ptr[0];  // Copy the drive letter.
     60 
     61     if (QueryDosDevice(drive, device_name, MAX_PATH) &&
     62         StartsWith(device_path.value(), device_name, true)) {
     63       *drive_letter_path = FilePath(drive +
     64           device_path.value().substr(wcslen(device_name)));
     65       return true;
     66     }
     67     // Move to the next drive letter string, which starts one
     68     // increment after the '\0' that terminates the current string.
     69     while (*drive_map_ptr++);
     70   }
     71 
     72   // No drive matched.  The path does not start with a device junction
     73   // that is mounted as a drive letter.  This means there is no drive
     74   // letter path to the volume that holds |device_path|, so fail.
     75   return false;
     76 }
     77 
     78 }  // namespace
     79 
     80 bool AbsolutePath(FilePath* path) {
     81   base::ThreadRestrictions::AssertIOAllowed();
     82   wchar_t file_path_buf[MAX_PATH];
     83   if (!_wfullpath(file_path_buf, path->value().c_str(), MAX_PATH))
     84     return false;
     85   *path = FilePath(file_path_buf);
     86   return true;
     87 }
     88 
     89 int CountFilesCreatedAfter(const FilePath& path,
     90                            const base::Time& comparison_time) {
     91   base::ThreadRestrictions::AssertIOAllowed();
     92 
     93   int file_count = 0;
     94   FILETIME comparison_filetime(comparison_time.ToFileTime());
     95 
     96   WIN32_FIND_DATA find_file_data;
     97   // All files in given dir
     98   std::wstring filename_spec = path.Append(L"*").value();
     99   HANDLE find_handle = FindFirstFile(filename_spec.c_str(), &find_file_data);
    100   if (find_handle != INVALID_HANDLE_VALUE) {
    101     do {
    102       // Don't count current or parent directories.
    103       if ((wcscmp(find_file_data.cFileName, L"..") == 0) ||
    104           (wcscmp(find_file_data.cFileName, L".") == 0))
    105         continue;
    106 
    107       long result = CompareFileTime(&find_file_data.ftCreationTime,  // NOLINT
    108                                     &comparison_filetime);
    109       // File was created after or on comparison time
    110       if ((result == 1) || (result == 0))
    111         ++file_count;
    112     } while (FindNextFile(find_handle,  &find_file_data));
    113     FindClose(find_handle);
    114   }
    115 
    116   return file_count;
    117 }
    118 
    119 bool Delete(const FilePath& path, bool recursive) {
    120   base::ThreadRestrictions::AssertIOAllowed();
    121 
    122   if (path.value().length() >= MAX_PATH)
    123     return false;
    124 
    125   if (!recursive) {
    126     // If not recursing, then first check to see if |path| is a directory.
    127     // If it is, then remove it with RemoveDirectory.
    128     base::PlatformFileInfo file_info;
    129     if (GetFileInfo(path, &file_info) && file_info.is_directory)
    130       return RemoveDirectory(path.value().c_str()) != 0;
    131 
    132     // Otherwise, it's a file, wildcard or non-existant. Try DeleteFile first
    133     // because it should be faster. If DeleteFile fails, then we fall through
    134     // to SHFileOperation, which will do the right thing.
    135     if (DeleteFile(path.value().c_str()) != 0)
    136       return true;
    137   }
    138 
    139   // SHFILEOPSTRUCT wants the path to be terminated with two NULLs,
    140   // so we have to use wcscpy because wcscpy_s writes non-NULLs
    141   // into the rest of the buffer.
    142   wchar_t double_terminated_path[MAX_PATH + 1] = {0};
    143 #pragma warning(suppress:4996)  // don't complain about wcscpy deprecation
    144   wcscpy(double_terminated_path, path.value().c_str());
    145 
    146   SHFILEOPSTRUCT file_operation = {0};
    147   file_operation.wFunc = FO_DELETE;
    148   file_operation.pFrom = double_terminated_path;
    149   file_operation.fFlags = FOF_NOERRORUI | FOF_SILENT | FOF_NOCONFIRMATION;
    150   if (!recursive)
    151     file_operation.fFlags |= FOF_NORECURSION | FOF_FILESONLY;
    152   int err = SHFileOperation(&file_operation);
    153 
    154   // Since we're passing flags to the operation telling it to be silent,
    155   // it's possible for the operation to be aborted/cancelled without err
    156   // being set (although MSDN doesn't give any scenarios for how this can
    157   // happen).  See MSDN for SHFileOperation and SHFILEOPTSTRUCT.
    158   if (file_operation.fAnyOperationsAborted)
    159     return false;
    160 
    161   // Some versions of Windows return ERROR_FILE_NOT_FOUND (0x2) when deleting
    162   // an empty directory and some return 0x402 when they should be returning
    163   // ERROR_FILE_NOT_FOUND. MSDN says Vista and up won't return 0x402.
    164   return (err == 0 || err == ERROR_FILE_NOT_FOUND || err == 0x402);
    165 }
    166 
    167 bool DeleteAfterReboot(const FilePath& path) {
    168   base::ThreadRestrictions::AssertIOAllowed();
    169 
    170   if (path.value().length() >= MAX_PATH)
    171     return false;
    172 
    173   return MoveFileEx(path.value().c_str(), NULL,
    174                     MOVEFILE_DELAY_UNTIL_REBOOT |
    175                         MOVEFILE_REPLACE_EXISTING) != FALSE;
    176 }
    177 
    178 bool Move(const FilePath& from_path, const FilePath& to_path) {
    179   base::ThreadRestrictions::AssertIOAllowed();
    180 
    181   // NOTE: I suspect we could support longer paths, but that would involve
    182   // analyzing all our usage of files.
    183   if (from_path.value().length() >= MAX_PATH ||
    184       to_path.value().length() >= MAX_PATH) {
    185     return false;
    186   }
    187   if (MoveFileEx(from_path.value().c_str(), to_path.value().c_str(),
    188                  MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING) != 0)
    189     return true;
    190 
    191   // Keep the last error value from MoveFileEx around in case the below
    192   // fails.
    193   bool ret = false;
    194   DWORD last_error = ::GetLastError();
    195 
    196   if (DirectoryExists(from_path)) {
    197     // MoveFileEx fails if moving directory across volumes. We will simulate
    198     // the move by using Copy and Delete. Ideally we could check whether
    199     // from_path and to_path are indeed in different volumes.
    200     ret = CopyAndDeleteDirectory(from_path, to_path);
    201   }
    202 
    203   if (!ret) {
    204     // Leave a clue about what went wrong so that it can be (at least) picked
    205     // up by a PLOG entry.
    206     ::SetLastError(last_error);
    207   }
    208 
    209   return ret;
    210 }
    211 
    212 bool ReplaceFile(const FilePath& from_path, const FilePath& to_path) {
    213   base::ThreadRestrictions::AssertIOAllowed();
    214 
    215   // Make sure that the target file exists.
    216   HANDLE target_file = ::CreateFile(
    217       to_path.value().c_str(),
    218       0,
    219       FILE_SHARE_READ | FILE_SHARE_WRITE,
    220       NULL,
    221       CREATE_NEW,
    222       FILE_ATTRIBUTE_NORMAL,
    223       NULL);
    224   if (target_file != INVALID_HANDLE_VALUE)
    225     ::CloseHandle(target_file);
    226   // When writing to a network share, we may not be able to change the ACLs.
    227   // Ignore ACL errors then (REPLACEFILE_IGNORE_MERGE_ERRORS).
    228   return ::ReplaceFile(to_path.value().c_str(),
    229       from_path.value().c_str(), NULL,
    230       REPLACEFILE_IGNORE_MERGE_ERRORS, NULL, NULL) ? true : false;
    231 }
    232 
    233 bool CopyFile(const FilePath& from_path, const FilePath& to_path) {
    234   base::ThreadRestrictions::AssertIOAllowed();
    235 
    236   // NOTE: I suspect we could support longer paths, but that would involve
    237   // analyzing all our usage of files.
    238   if (from_path.value().length() >= MAX_PATH ||
    239       to_path.value().length() >= MAX_PATH) {
    240     return false;
    241   }
    242   return (::CopyFile(from_path.value().c_str(), to_path.value().c_str(),
    243                      false) != 0);
    244 }
    245 
    246 bool ShellCopy(const FilePath& from_path, const FilePath& to_path,
    247                bool recursive) {
    248   base::ThreadRestrictions::AssertIOAllowed();
    249 
    250   // NOTE: I suspect we could support longer paths, but that would involve
    251   // analyzing all our usage of files.
    252   if (from_path.value().length() >= MAX_PATH ||
    253       to_path.value().length() >= MAX_PATH) {
    254     return false;
    255   }
    256 
    257   // SHFILEOPSTRUCT wants the path to be terminated with two NULLs,
    258   // so we have to use wcscpy because wcscpy_s writes non-NULLs
    259   // into the rest of the buffer.
    260   wchar_t double_terminated_path_from[MAX_PATH + 1] = {0};
    261   wchar_t double_terminated_path_to[MAX_PATH + 1] = {0};
    262 #pragma warning(suppress:4996)  // don't complain about wcscpy deprecation
    263   wcscpy(double_terminated_path_from, from_path.value().c_str());
    264 #pragma warning(suppress:4996)  // don't complain about wcscpy deprecation
    265   wcscpy(double_terminated_path_to, to_path.value().c_str());
    266 
    267   SHFILEOPSTRUCT file_operation = {0};
    268   file_operation.wFunc = FO_COPY;
    269   file_operation.pFrom = double_terminated_path_from;
    270   file_operation.pTo = double_terminated_path_to;
    271   file_operation.fFlags = FOF_NOERRORUI | FOF_SILENT | FOF_NOCONFIRMATION |
    272                           FOF_NOCONFIRMMKDIR;
    273   if (!recursive)
    274     file_operation.fFlags |= FOF_NORECURSION | FOF_FILESONLY;
    275 
    276   return (SHFileOperation(&file_operation) == 0);
    277 }
    278 
    279 bool CopyDirectory(const FilePath& from_path, const FilePath& to_path,
    280                    bool recursive) {
    281   base::ThreadRestrictions::AssertIOAllowed();
    282 
    283   if (recursive)
    284     return ShellCopy(from_path, to_path, true);
    285 
    286   // The following code assumes that from path is a directory.
    287   DCHECK(DirectoryExists(from_path));
    288 
    289   // Instead of creating a new directory, we copy the old one to include the
    290   // security information of the folder as part of the copy.
    291   if (!PathExists(to_path)) {
    292     // Except that Vista fails to do that, and instead do a recursive copy if
    293     // the target directory doesn't exist.
    294     if (base::win::GetVersion() >= base::win::VERSION_VISTA)
    295       CreateDirectory(to_path);
    296     else
    297       ShellCopy(from_path, to_path, false);
    298   }
    299 
    300   FilePath directory = from_path.Append(L"*.*");
    301   return ShellCopy(directory, to_path, false);
    302 }
    303 
    304 bool CopyAndDeleteDirectory(const FilePath& from_path,
    305                             const FilePath& to_path) {
    306   base::ThreadRestrictions::AssertIOAllowed();
    307   if (CopyDirectory(from_path, to_path, true)) {
    308     if (Delete(from_path, true)) {
    309       return true;
    310     }
    311     // Like Move, this function is not transactional, so we just
    312     // leave the copied bits behind if deleting from_path fails.
    313     // If to_path exists previously then we have already overwritten
    314     // it by now, we don't get better off by deleting the new bits.
    315   }
    316   return false;
    317 }
    318 
    319 
    320 bool PathExists(const FilePath& path) {
    321   base::ThreadRestrictions::AssertIOAllowed();
    322   return (GetFileAttributes(path.value().c_str()) != INVALID_FILE_ATTRIBUTES);
    323 }
    324 
    325 bool PathIsWritable(const FilePath& path) {
    326   base::ThreadRestrictions::AssertIOAllowed();
    327   HANDLE dir =
    328       CreateFile(path.value().c_str(), FILE_ADD_FILE, kFileShareAll,
    329                  NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
    330 
    331   if (dir == INVALID_HANDLE_VALUE)
    332     return false;
    333 
    334   CloseHandle(dir);
    335   return true;
    336 }
    337 
    338 bool DirectoryExists(const FilePath& path) {
    339   base::ThreadRestrictions::AssertIOAllowed();
    340   DWORD fileattr = GetFileAttributes(path.value().c_str());
    341   if (fileattr != INVALID_FILE_ATTRIBUTES)
    342     return (fileattr & FILE_ATTRIBUTE_DIRECTORY) != 0;
    343   return false;
    344 }
    345 
    346 bool GetFileCreationLocalTimeFromHandle(HANDLE file_handle,
    347                                         LPSYSTEMTIME creation_time) {
    348   base::ThreadRestrictions::AssertIOAllowed();
    349   if (!file_handle)
    350     return false;
    351 
    352   FILETIME utc_filetime;
    353   if (!GetFileTime(file_handle, &utc_filetime, NULL, NULL))
    354     return false;
    355 
    356   FILETIME local_filetime;
    357   if (!FileTimeToLocalFileTime(&utc_filetime, &local_filetime))
    358     return false;
    359 
    360   return !!FileTimeToSystemTime(&local_filetime, creation_time);
    361 }
    362 
    363 bool GetFileCreationLocalTime(const std::wstring& filename,
    364                               LPSYSTEMTIME creation_time) {
    365   base::ThreadRestrictions::AssertIOAllowed();
    366   base::win::ScopedHandle file_handle(
    367       CreateFile(filename.c_str(), GENERIC_READ, kFileShareAll, NULL,
    368                  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL));
    369   return GetFileCreationLocalTimeFromHandle(file_handle.Get(), creation_time);
    370 }
    371 
    372 bool ResolveShortcut(FilePath* path) {
    373   base::ThreadRestrictions::AssertIOAllowed();
    374 
    375   HRESULT result;
    376   base::win::ScopedComPtr<IShellLink> i_shell_link;
    377   bool is_resolved = false;
    378 
    379   // Get pointer to the IShellLink interface
    380   result = i_shell_link.CreateInstance(CLSID_ShellLink, NULL,
    381                                        CLSCTX_INPROC_SERVER);
    382   if (SUCCEEDED(result)) {
    383     base::win::ScopedComPtr<IPersistFile> persist;
    384     // Query IShellLink for the IPersistFile interface
    385     result = persist.QueryFrom(i_shell_link);
    386     if (SUCCEEDED(result)) {
    387       WCHAR temp_path[MAX_PATH];
    388       // Load the shell link
    389       result = persist->Load(path->value().c_str(), STGM_READ);
    390       if (SUCCEEDED(result)) {
    391         // Try to find the target of a shortcut
    392         result = i_shell_link->Resolve(0, SLR_NO_UI);
    393         if (SUCCEEDED(result)) {
    394           result = i_shell_link->GetPath(temp_path, MAX_PATH,
    395                                   NULL, SLGP_UNCPRIORITY);
    396           *path = FilePath(temp_path);
    397           is_resolved = true;
    398         }
    399       }
    400     }
    401   }
    402 
    403   return is_resolved;
    404 }
    405 
    406 bool CreateShortcutLink(const wchar_t *source, const wchar_t *destination,
    407                         const wchar_t *working_dir, const wchar_t *arguments,
    408                         const wchar_t *description, const wchar_t *icon,
    409                         int icon_index, const wchar_t* app_id) {
    410   base::ThreadRestrictions::AssertIOAllowed();
    411 
    412   // Length of arguments and description must be less than MAX_PATH.
    413   DCHECK(lstrlen(arguments) < MAX_PATH);
    414   DCHECK(lstrlen(description) < MAX_PATH);
    415 
    416   base::win::ScopedComPtr<IShellLink> i_shell_link;
    417   base::win::ScopedComPtr<IPersistFile> i_persist_file;
    418 
    419   // Get pointer to the IShellLink interface
    420   HRESULT result = i_shell_link.CreateInstance(CLSID_ShellLink, NULL,
    421                                                CLSCTX_INPROC_SERVER);
    422   if (FAILED(result))
    423     return false;
    424 
    425   // Query IShellLink for the IPersistFile interface
    426   result = i_persist_file.QueryFrom(i_shell_link);
    427   if (FAILED(result))
    428     return false;
    429 
    430   if (FAILED(i_shell_link->SetPath(source)))
    431     return false;
    432 
    433   if (working_dir && FAILED(i_shell_link->SetWorkingDirectory(working_dir)))
    434     return false;
    435 
    436   if (arguments && FAILED(i_shell_link->SetArguments(arguments)))
    437     return false;
    438 
    439   if (description && FAILED(i_shell_link->SetDescription(description)))
    440     return false;
    441 
    442   if (icon && FAILED(i_shell_link->SetIconLocation(icon, icon_index)))
    443     return false;
    444 
    445   if (app_id && (base::win::GetVersion() >= base::win::VERSION_WIN7)) {
    446     base::win::ScopedComPtr<IPropertyStore> property_store;
    447     if (FAILED(property_store.QueryFrom(i_shell_link)))
    448       return false;
    449 
    450     if (!base::win::SetAppIdForPropertyStore(property_store, app_id))
    451       return false;
    452   }
    453 
    454   result = i_persist_file->Save(destination, TRUE);
    455   return SUCCEEDED(result);
    456 }
    457 
    458 bool UpdateShortcutLink(const wchar_t *source, const wchar_t *destination,
    459                         const wchar_t *working_dir, const wchar_t *arguments,
    460                         const wchar_t *description, const wchar_t *icon,
    461                         int icon_index, const wchar_t* app_id) {
    462   base::ThreadRestrictions::AssertIOAllowed();
    463 
    464   // Length of arguments and description must be less than MAX_PATH.
    465   DCHECK(lstrlen(arguments) < MAX_PATH);
    466   DCHECK(lstrlen(description) < MAX_PATH);
    467 
    468   // Get pointer to the IPersistFile interface and load existing link
    469   base::win::ScopedComPtr<IShellLink> i_shell_link;
    470   if (FAILED(i_shell_link.CreateInstance(CLSID_ShellLink, NULL,
    471                                          CLSCTX_INPROC_SERVER)))
    472     return false;
    473 
    474   base::win::ScopedComPtr<IPersistFile> i_persist_file;
    475   if (FAILED(i_persist_file.QueryFrom(i_shell_link)))
    476     return false;
    477 
    478   if (FAILED(i_persist_file->Load(destination, STGM_READWRITE)))
    479     return false;
    480 
    481   if (source && FAILED(i_shell_link->SetPath(source)))
    482     return false;
    483 
    484   if (working_dir && FAILED(i_shell_link->SetWorkingDirectory(working_dir)))
    485     return false;
    486 
    487   if (arguments && FAILED(i_shell_link->SetArguments(arguments)))
    488     return false;
    489 
    490   if (description && FAILED(i_shell_link->SetDescription(description)))
    491     return false;
    492 
    493   if (icon && FAILED(i_shell_link->SetIconLocation(icon, icon_index)))
    494     return false;
    495 
    496   if (app_id && base::win::GetVersion() >= base::win::VERSION_WIN7) {
    497     base::win::ScopedComPtr<IPropertyStore> property_store;
    498     if (FAILED(property_store.QueryFrom(i_shell_link)))
    499       return false;
    500 
    501     if (!base::win::SetAppIdForPropertyStore(property_store, app_id))
    502       return false;
    503   }
    504 
    505   HRESULT result = i_persist_file->Save(destination, TRUE);
    506 
    507   i_persist_file.Release();
    508   i_shell_link.Release();
    509 
    510   // If we successfully updated the icon, notify the shell that we have done so.
    511   if (SUCCEEDED(result)) {
    512     SHChangeNotify(SHCNE_ASSOCCHANGED, SHCNF_IDLIST | SHCNF_FLUSHNOWAIT,
    513                    NULL, NULL);
    514   }
    515 
    516   return SUCCEEDED(result);
    517 }
    518 
    519 bool TaskbarPinShortcutLink(const wchar_t* shortcut) {
    520   base::ThreadRestrictions::AssertIOAllowed();
    521 
    522   // "Pin to taskbar" is only supported after Win7.
    523   if (base::win::GetVersion() < base::win::VERSION_WIN7)
    524     return false;
    525 
    526   int result = reinterpret_cast<int>(ShellExecute(NULL, L"taskbarpin", shortcut,
    527       NULL, NULL, 0));
    528   return result > 32;
    529 }
    530 
    531 bool TaskbarUnpinShortcutLink(const wchar_t* shortcut) {
    532   base::ThreadRestrictions::AssertIOAllowed();
    533 
    534   // "Unpin from taskbar" is only supported after Win7.
    535   if (base::win::GetVersion() < base::win::VERSION_WIN7)
    536     return false;
    537 
    538   int result = reinterpret_cast<int>(ShellExecute(NULL, L"taskbarunpin",
    539       shortcut, NULL, NULL, 0));
    540   return result > 32;
    541 }
    542 
    543 bool GetTempDir(FilePath* path) {
    544   base::ThreadRestrictions::AssertIOAllowed();
    545 
    546   wchar_t temp_path[MAX_PATH + 1];
    547   DWORD path_len = ::GetTempPath(MAX_PATH, temp_path);
    548   if (path_len >= MAX_PATH || path_len <= 0)
    549     return false;
    550   // TODO(evanm): the old behavior of this function was to always strip the
    551   // trailing slash.  We duplicate this here, but it shouldn't be necessary
    552   // when everyone is using the appropriate FilePath APIs.
    553   *path = FilePath(temp_path).StripTrailingSeparators();
    554   return true;
    555 }
    556 
    557 bool GetShmemTempDir(FilePath* path) {
    558   return GetTempDir(path);
    559 }
    560 
    561 bool CreateTemporaryFile(FilePath* path) {
    562   base::ThreadRestrictions::AssertIOAllowed();
    563 
    564   FilePath temp_file;
    565 
    566   if (!GetTempDir(path))
    567     return false;
    568 
    569   if (CreateTemporaryFileInDir(*path, &temp_file)) {
    570     *path = temp_file;
    571     return true;
    572   }
    573 
    574   return false;
    575 }
    576 
    577 FILE* CreateAndOpenTemporaryShmemFile(FilePath* path) {
    578   base::ThreadRestrictions::AssertIOAllowed();
    579   return CreateAndOpenTemporaryFile(path);
    580 }
    581 
    582 // On POSIX we have semantics to create and open a temporary file
    583 // atomically.
    584 // TODO(jrg): is there equivalent call to use on Windows instead of
    585 // going 2-step?
    586 FILE* CreateAndOpenTemporaryFileInDir(const FilePath& dir, FilePath* path) {
    587   base::ThreadRestrictions::AssertIOAllowed();
    588   if (!CreateTemporaryFileInDir(dir, path)) {
    589     return NULL;
    590   }
    591   // Open file in binary mode, to avoid problems with fwrite. On Windows
    592   // it replaces \n's with \r\n's, which may surprise you.
    593   // Reference: http://msdn.microsoft.com/en-us/library/h9t88zwz(VS.71).aspx
    594   return OpenFile(*path, "wb+");
    595 }
    596 
    597 bool CreateTemporaryFileInDir(const FilePath& dir,
    598                               FilePath* temp_file) {
    599   base::ThreadRestrictions::AssertIOAllowed();
    600 
    601   wchar_t temp_name[MAX_PATH + 1];
    602 
    603   if (!GetTempFileName(dir.value().c_str(), L"", 0, temp_name)) {
    604     PLOG(WARNING) << "Failed to get temporary file name in " << dir.value();
    605     return false;
    606   }
    607 
    608   DWORD path_len = GetLongPathName(temp_name, temp_name, MAX_PATH);
    609   if (path_len > MAX_PATH + 1 || path_len == 0) {
    610     PLOG(WARNING) << "Failed to get long path name for " << temp_name;
    611     return false;
    612   }
    613 
    614   std::wstring temp_file_str;
    615   temp_file_str.assign(temp_name, path_len);
    616   *temp_file = FilePath(temp_file_str);
    617   return true;
    618 }
    619 
    620 bool CreateTemporaryDirInDir(const FilePath& base_dir,
    621                              const FilePath::StringType& prefix,
    622                              FilePath* new_dir) {
    623   base::ThreadRestrictions::AssertIOAllowed();
    624 
    625   FilePath path_to_create;
    626   srand(static_cast<uint32>(time(NULL)));
    627 
    628   for (int count = 0; count < 50; ++count) {
    629     // Try create a new temporary directory with random generated name. If
    630     // the one exists, keep trying another path name until we reach some limit.
    631     string16 new_dir_name;
    632     new_dir_name.assign(prefix);
    633     new_dir_name.append(base::IntToString16(rand() % kint16max));
    634 
    635     path_to_create = base_dir.Append(new_dir_name);
    636     if (::CreateDirectory(path_to_create.value().c_str(), NULL)) {
    637       *new_dir = path_to_create;
    638       return true;
    639     }
    640   }
    641 
    642   return false;
    643 }
    644 
    645 bool CreateNewTempDirectory(const FilePath::StringType& prefix,
    646                             FilePath* new_temp_path) {
    647   base::ThreadRestrictions::AssertIOAllowed();
    648 
    649   FilePath system_temp_dir;
    650   if (!GetTempDir(&system_temp_dir))
    651     return false;
    652 
    653   return CreateTemporaryDirInDir(system_temp_dir, prefix, new_temp_path);
    654 }
    655 
    656 bool CreateDirectory(const FilePath& full_path) {
    657   base::ThreadRestrictions::AssertIOAllowed();
    658 
    659   // If the path exists, we've succeeded if it's a directory, failed otherwise.
    660   const wchar_t* full_path_str = full_path.value().c_str();
    661   DWORD fileattr = ::GetFileAttributes(full_path_str);
    662   if (fileattr != INVALID_FILE_ATTRIBUTES) {
    663     if ((fileattr & FILE_ATTRIBUTE_DIRECTORY) != 0) {
    664       DVLOG(1) << "CreateDirectory(" << full_path_str << "), "
    665                << "directory already exists.";
    666       return true;
    667     }
    668     LOG(WARNING) << "CreateDirectory(" << full_path_str << "), "
    669                  << "conflicts with existing file.";
    670     return false;
    671   }
    672 
    673   // Invariant:  Path does not exist as file or directory.
    674 
    675   // Attempt to create the parent recursively.  This will immediately return
    676   // true if it already exists, otherwise will create all required parent
    677   // directories starting with the highest-level missing parent.
    678   FilePath parent_path(full_path.DirName());
    679   if (parent_path.value() == full_path.value()) {
    680     return false;
    681   }
    682   if (!CreateDirectory(parent_path)) {
    683     DLOG(WARNING) << "Failed to create one of the parent directories.";
    684     return false;
    685   }
    686 
    687   if (!::CreateDirectory(full_path_str, NULL)) {
    688     DWORD error_code = ::GetLastError();
    689     if (error_code == ERROR_ALREADY_EXISTS && DirectoryExists(full_path)) {
    690       // This error code ERROR_ALREADY_EXISTS doesn't indicate whether we
    691       // were racing with someone creating the same directory, or a file
    692       // with the same path.  If DirectoryExists() returns true, we lost the
    693       // race to create the same directory.
    694       return true;
    695     } else {
    696       LOG(WARNING) << "Failed to create directory " << full_path_str
    697                    << ", last error is " << error_code << ".";
    698       return false;
    699     }
    700   } else {
    701     return true;
    702   }
    703 }
    704 
    705 bool GetFileInfo(const FilePath& file_path, base::PlatformFileInfo* results) {
    706   base::ThreadRestrictions::AssertIOAllowed();
    707 
    708   WIN32_FILE_ATTRIBUTE_DATA attr;
    709   if (!GetFileAttributesEx(file_path.value().c_str(),
    710                            GetFileExInfoStandard, &attr)) {
    711     return false;
    712   }
    713 
    714   ULARGE_INTEGER size;
    715   size.HighPart = attr.nFileSizeHigh;
    716   size.LowPart = attr.nFileSizeLow;
    717   results->size = size.QuadPart;
    718 
    719   results->is_directory =
    720       (attr.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
    721   results->last_modified = base::Time::FromFileTime(attr.ftLastWriteTime);
    722   results->last_accessed = base::Time::FromFileTime(attr.ftLastAccessTime);
    723   results->creation_time = base::Time::FromFileTime(attr.ftCreationTime);
    724 
    725   return true;
    726 }
    727 
    728 FILE* OpenFile(const FilePath& filename, const char* mode) {
    729   base::ThreadRestrictions::AssertIOAllowed();
    730   std::wstring w_mode = ASCIIToWide(std::string(mode));
    731   return _wfsopen(filename.value().c_str(), w_mode.c_str(), _SH_DENYNO);
    732 }
    733 
    734 FILE* OpenFile(const std::string& filename, const char* mode) {
    735   base::ThreadRestrictions::AssertIOAllowed();
    736   return _fsopen(filename.c_str(), mode, _SH_DENYNO);
    737 }
    738 
    739 int ReadFile(const FilePath& filename, char* data, int size) {
    740   base::ThreadRestrictions::AssertIOAllowed();
    741   base::win::ScopedHandle file(CreateFile(filename.value().c_str(),
    742                                           GENERIC_READ,
    743                                           FILE_SHARE_READ | FILE_SHARE_WRITE,
    744                                           NULL,
    745                                           OPEN_EXISTING,
    746                                           FILE_FLAG_SEQUENTIAL_SCAN,
    747                                           NULL));
    748   if (!file)
    749     return -1;
    750 
    751   DWORD read;
    752   if (::ReadFile(file, data, size, &read, NULL) &&
    753       static_cast<int>(read) == size)
    754     return read;
    755   return -1;
    756 }
    757 
    758 int WriteFile(const FilePath& filename, const char* data, int size) {
    759   base::ThreadRestrictions::AssertIOAllowed();
    760   base::win::ScopedHandle file(CreateFile(filename.value().c_str(),
    761                                           GENERIC_WRITE,
    762                                           0,
    763                                           NULL,
    764                                           CREATE_ALWAYS,
    765                                           0,
    766                                           NULL));
    767   if (!file) {
    768     LOG(WARNING) << "CreateFile failed for path " << filename.value()
    769                  << " error code=" << GetLastError();
    770     return -1;
    771   }
    772 
    773   DWORD written;
    774   BOOL result = ::WriteFile(file, data, size, &written, NULL);
    775   if (result && static_cast<int>(written) == size)
    776     return written;
    777 
    778   if (!result) {
    779     // WriteFile failed.
    780     LOG(WARNING) << "writing file " << filename.value()
    781                  << " failed, error code=" << GetLastError();
    782   } else {
    783     // Didn't write all the bytes.
    784     LOG(WARNING) << "wrote" << written << " bytes to " <<
    785         filename.value() << " expected " << size;
    786   }
    787   return -1;
    788 }
    789 
    790 bool RenameFileAndResetSecurityDescriptor(const FilePath& source_file_path,
    791                                           const FilePath& target_file_path) {
    792   base::ThreadRestrictions::AssertIOAllowed();
    793 
    794   // The parameters to SHFileOperation must be terminated with 2 NULL chars.
    795   std::wstring source = source_file_path.value();
    796   std::wstring target = target_file_path.value();
    797 
    798   source.append(1, L'\0');
    799   target.append(1, L'\0');
    800 
    801   SHFILEOPSTRUCT move_info = {0};
    802   move_info.wFunc = FO_MOVE;
    803   move_info.pFrom = source.c_str();
    804   move_info.pTo = target.c_str();
    805   move_info.fFlags = FOF_SILENT | FOF_NOCONFIRMATION | FOF_NOERRORUI |
    806                      FOF_NOCONFIRMMKDIR | FOF_NOCOPYSECURITYATTRIBS;
    807 
    808   if (0 != SHFileOperation(&move_info))
    809     return false;
    810 
    811   return true;
    812 }
    813 
    814 // Gets the current working directory for the process.
    815 bool GetCurrentDirectory(FilePath* dir) {
    816   base::ThreadRestrictions::AssertIOAllowed();
    817 
    818   wchar_t system_buffer[MAX_PATH];
    819   system_buffer[0] = 0;
    820   DWORD len = ::GetCurrentDirectory(MAX_PATH, system_buffer);
    821   if (len == 0 || len > MAX_PATH)
    822     return false;
    823   // TODO(evanm): the old behavior of this function was to always strip the
    824   // trailing slash.  We duplicate this here, but it shouldn't be necessary
    825   // when everyone is using the appropriate FilePath APIs.
    826   std::wstring dir_str(system_buffer);
    827   *dir = FilePath(dir_str).StripTrailingSeparators();
    828   return true;
    829 }
    830 
    831 // Sets the current working directory for the process.
    832 bool SetCurrentDirectory(const FilePath& directory) {
    833   base::ThreadRestrictions::AssertIOAllowed();
    834   BOOL ret = ::SetCurrentDirectory(directory.value().c_str());
    835   return ret != 0;
    836 }
    837 
    838 ///////////////////////////////////////////////
    839 // FileEnumerator
    840 
    841 FileEnumerator::FileEnumerator(const FilePath& root_path,
    842                                bool recursive,
    843                                FileEnumerator::FILE_TYPE file_type)
    844     : recursive_(recursive),
    845       file_type_(file_type),
    846       has_find_data_(false),
    847       find_handle_(INVALID_HANDLE_VALUE) {
    848   // INCLUDE_DOT_DOT must not be specified if recursive.
    849   DCHECK(!(recursive && (INCLUDE_DOT_DOT & file_type_)));
    850   pending_paths_.push(root_path);
    851 }
    852 
    853 FileEnumerator::FileEnumerator(const FilePath& root_path,
    854                                bool recursive,
    855                                FileEnumerator::FILE_TYPE file_type,
    856                                const FilePath::StringType& pattern)
    857     : recursive_(recursive),
    858       file_type_(file_type),
    859       has_find_data_(false),
    860       pattern_(pattern),
    861       find_handle_(INVALID_HANDLE_VALUE) {
    862   // INCLUDE_DOT_DOT must not be specified if recursive.
    863   DCHECK(!(recursive && (INCLUDE_DOT_DOT & file_type_)));
    864   pending_paths_.push(root_path);
    865 }
    866 
    867 FileEnumerator::~FileEnumerator() {
    868   if (find_handle_ != INVALID_HANDLE_VALUE)
    869     FindClose(find_handle_);
    870 }
    871 
    872 void FileEnumerator::GetFindInfo(FindInfo* info) {
    873   DCHECK(info);
    874 
    875   if (!has_find_data_)
    876     return;
    877 
    878   memcpy(info, &find_data_, sizeof(*info));
    879 }
    880 
    881 bool FileEnumerator::IsDirectory(const FindInfo& info) {
    882   return (info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
    883 }
    884 
    885 // static
    886 FilePath FileEnumerator::GetFilename(const FindInfo& find_info) {
    887   return FilePath(find_info.cFileName);
    888 }
    889 
    890 FilePath FileEnumerator::Next() {
    891   base::ThreadRestrictions::AssertIOAllowed();
    892 
    893   while (has_find_data_ || !pending_paths_.empty()) {
    894     if (!has_find_data_) {
    895       // The last find FindFirstFile operation is done, prepare a new one.
    896       root_path_ = pending_paths_.top();
    897       pending_paths_.pop();
    898 
    899       // Start a new find operation.
    900       FilePath src = root_path_;
    901 
    902       if (pattern_.empty())
    903         src = src.Append(L"*");  // No pattern = match everything.
    904       else
    905         src = src.Append(pattern_);
    906 
    907       find_handle_ = FindFirstFile(src.value().c_str(), &find_data_);
    908       has_find_data_ = true;
    909     } else {
    910       // Search for the next file/directory.
    911       if (!FindNextFile(find_handle_, &find_data_)) {
    912         FindClose(find_handle_);
    913         find_handle_ = INVALID_HANDLE_VALUE;
    914       }
    915     }
    916 
    917     if (INVALID_HANDLE_VALUE == find_handle_) {
    918       has_find_data_ = false;
    919 
    920       // This is reached when we have finished a directory and are advancing to
    921       // the next one in the queue. We applied the pattern (if any) to the files
    922       // in the root search directory, but for those directories which were
    923       // matched, we want to enumerate all files inside them. This will happen
    924       // when the handle is empty.
    925       pattern_ = FilePath::StringType();
    926 
    927       continue;
    928     }
    929 
    930     FilePath cur_file(find_data_.cFileName);
    931     if (ShouldSkip(cur_file))
    932       continue;
    933 
    934     // Construct the absolute filename.
    935     cur_file = root_path_.Append(find_data_.cFileName);
    936 
    937     if (find_data_.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
    938       if (recursive_) {
    939         // If |cur_file| is a directory, and we are doing recursive searching,
    940         // add it to pending_paths_ so we scan it after we finish scanning this
    941         // directory.
    942         pending_paths_.push(cur_file);
    943       }
    944       if (file_type_ & FileEnumerator::DIRECTORIES)
    945         return cur_file;
    946     } else if (file_type_ & FileEnumerator::FILES) {
    947       return cur_file;
    948     }
    949   }
    950 
    951   return FilePath();
    952 }
    953 
    954 ///////////////////////////////////////////////
    955 // MemoryMappedFile
    956 
    957 MemoryMappedFile::MemoryMappedFile()
    958     : file_(INVALID_HANDLE_VALUE),
    959       file_mapping_(INVALID_HANDLE_VALUE),
    960       data_(NULL),
    961       length_(INVALID_FILE_SIZE) {
    962 }
    963 
    964 bool MemoryMappedFile::InitializeAsImageSection(const FilePath& file_name) {
    965   if (IsValid())
    966     return false;
    967   file_ = base::CreatePlatformFile(
    968       file_name, base::PLATFORM_FILE_OPEN | base::PLATFORM_FILE_READ,
    969       NULL, NULL);
    970 
    971   if (file_ == base::kInvalidPlatformFileValue) {
    972     LOG(ERROR) << "Couldn't open " << file_name.value();
    973     return false;
    974   }
    975 
    976   if (!MapFileToMemoryInternalEx(SEC_IMAGE)) {
    977     CloseHandles();
    978     return false;
    979   }
    980 
    981   return true;
    982 }
    983 
    984 bool MemoryMappedFile::MapFileToMemoryInternal() {
    985   return MapFileToMemoryInternalEx(0);
    986 }
    987 
    988 bool MemoryMappedFile::MapFileToMemoryInternalEx(int flags) {
    989   base::ThreadRestrictions::AssertIOAllowed();
    990 
    991   if (file_ == INVALID_HANDLE_VALUE)
    992     return false;
    993 
    994   length_ = ::GetFileSize(file_, NULL);
    995   if (length_ == INVALID_FILE_SIZE)
    996     return false;
    997 
    998   file_mapping_ = ::CreateFileMapping(file_, NULL, PAGE_READONLY | flags,
    999                                       0, 0, NULL);
   1000   if (!file_mapping_) {
   1001     // According to msdn, system error codes are only reserved up to 15999.
   1002     // http://msdn.microsoft.com/en-us/library/ms681381(v=VS.85).aspx.
   1003     UMA_HISTOGRAM_ENUMERATION("MemoryMappedFile.CreateFileMapping",
   1004                               logging::GetLastSystemErrorCode(), 16000);
   1005     return false;
   1006   }
   1007 
   1008   data_ = static_cast<uint8*>(
   1009       ::MapViewOfFile(file_mapping_, FILE_MAP_READ, 0, 0, 0));
   1010   if (!data_) {
   1011     UMA_HISTOGRAM_ENUMERATION("MemoryMappedFile.MapViewOfFile",
   1012                               logging::GetLastSystemErrorCode(), 16000);
   1013   }
   1014   return data_ != NULL;
   1015 }
   1016 
   1017 void MemoryMappedFile::CloseHandles() {
   1018   if (data_)
   1019     ::UnmapViewOfFile(data_);
   1020   if (file_mapping_ != INVALID_HANDLE_VALUE)
   1021     ::CloseHandle(file_mapping_);
   1022   if (file_ != INVALID_HANDLE_VALUE)
   1023     ::CloseHandle(file_);
   1024 
   1025   data_ = NULL;
   1026   file_mapping_ = file_ = INVALID_HANDLE_VALUE;
   1027   length_ = INVALID_FILE_SIZE;
   1028 }
   1029 
   1030 bool HasFileBeenModifiedSince(const FileEnumerator::FindInfo& find_info,
   1031                               const base::Time& cutoff_time) {
   1032   base::ThreadRestrictions::AssertIOAllowed();
   1033   long result = CompareFileTime(&find_info.ftLastWriteTime,  // NOLINT
   1034                                 &cutoff_time.ToFileTime());
   1035   return result == 1 || result == 0;
   1036 }
   1037 
   1038 bool NormalizeFilePath(const FilePath& path, FilePath* real_path) {
   1039   base::ThreadRestrictions::AssertIOAllowed();
   1040   FilePath mapped_file;
   1041   if (!NormalizeToNativeFilePath(path, &mapped_file))
   1042     return false;
   1043   // NormalizeToNativeFilePath() will return a path that starts with
   1044   // "\Device\Harddisk...".  Helper DevicePathToDriveLetterPath()
   1045   // will find a drive letter which maps to the path's device, so
   1046   // that we return a path starting with a drive letter.
   1047   return DevicePathToDriveLetterPath(mapped_file, real_path);
   1048 }
   1049 
   1050 bool NormalizeToNativeFilePath(const FilePath& path, FilePath* nt_path) {
   1051   base::ThreadRestrictions::AssertIOAllowed();
   1052   // In Vista, GetFinalPathNameByHandle() would give us the real path
   1053   // from a file handle.  If we ever deprecate XP, consider changing the
   1054   // code below to a call to GetFinalPathNameByHandle().  The method this
   1055   // function uses is explained in the following msdn article:
   1056   // http://msdn.microsoft.com/en-us/library/aa366789(VS.85).aspx
   1057   base::win::ScopedHandle file_handle(
   1058       ::CreateFile(path.value().c_str(),
   1059                    GENERIC_READ,
   1060                    kFileShareAll,
   1061                    NULL,
   1062                    OPEN_EXISTING,
   1063                    FILE_ATTRIBUTE_NORMAL,
   1064                    NULL));
   1065   if (!file_handle)
   1066     return false;
   1067 
   1068   // Create a file mapping object.  Can't easily use MemoryMappedFile, because
   1069   // we only map the first byte, and need direct access to the handle. You can
   1070   // not map an empty file, this call fails in that case.
   1071   base::win::ScopedHandle file_map_handle(
   1072       ::CreateFileMapping(file_handle.Get(),
   1073                           NULL,
   1074                           PAGE_READONLY,
   1075                           0,
   1076                           1,  // Just one byte.  No need to look at the data.
   1077                           NULL));
   1078   if (!file_map_handle)
   1079     return false;
   1080 
   1081   // Use a view of the file to get the path to the file.
   1082   void* file_view = MapViewOfFile(file_map_handle.Get(),
   1083                                   FILE_MAP_READ, 0, 0, 1);
   1084   if (!file_view)
   1085     return false;
   1086 
   1087   // The expansion of |path| into a full path may make it longer.
   1088   // GetMappedFileName() will fail if the result is longer than MAX_PATH.
   1089   // Pad a bit to be safe.  If kMaxPathLength is ever changed to be less
   1090   // than MAX_PATH, it would be nessisary to test that GetMappedFileName()
   1091   // not return kMaxPathLength.  This would mean that only part of the
   1092   // path fit in |mapped_file_path|.
   1093   const int kMaxPathLength = MAX_PATH + 10;
   1094   wchar_t mapped_file_path[kMaxPathLength];
   1095   bool success = false;
   1096   HANDLE cp = GetCurrentProcess();
   1097   if (::GetMappedFileNameW(cp, file_view, mapped_file_path, kMaxPathLength)) {
   1098     *nt_path = FilePath(mapped_file_path);
   1099     success = true;
   1100   }
   1101   ::UnmapViewOfFile(file_view);
   1102   return success;
   1103 }
   1104 
   1105 bool PreReadImage(const wchar_t* file_path, size_t size_to_read,
   1106                   size_t step_size) {
   1107   base::ThreadRestrictions::AssertIOAllowed();
   1108   if (base::win::GetVersion() > base::win::VERSION_XP) {
   1109     // Vista+ branch. On these OSes, the forced reads through the DLL actually
   1110     // slows warm starts. The solution is to sequentially read file contents
   1111     // with an optional cap on total amount to read.
   1112     base::win::ScopedHandle file(
   1113         CreateFile(file_path,
   1114                    GENERIC_READ,
   1115                    FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
   1116                    NULL,
   1117                    OPEN_EXISTING,
   1118                    FILE_FLAG_SEQUENTIAL_SCAN,
   1119                    NULL));
   1120 
   1121     if (!file.IsValid())
   1122       return false;
   1123 
   1124     // Default to 1MB sequential reads.
   1125     const DWORD actual_step_size = std::max(static_cast<DWORD>(step_size),
   1126                                             static_cast<DWORD>(1024*1024));
   1127     LPVOID buffer = ::VirtualAlloc(NULL,
   1128                                    actual_step_size,
   1129                                    MEM_COMMIT,
   1130                                    PAGE_READWRITE);
   1131 
   1132     if (buffer == NULL)
   1133       return false;
   1134 
   1135     DWORD len;
   1136     size_t total_read = 0;
   1137     while (::ReadFile(file, buffer, actual_step_size, &len, NULL) &&
   1138            len > 0 &&
   1139            (size_to_read ? total_read < size_to_read : true)) {
   1140       total_read += static_cast<size_t>(len);
   1141     }
   1142     ::VirtualFree(buffer, 0, MEM_RELEASE);
   1143   } else {
   1144     // WinXP branch. Here, reading the DLL from disk doesn't do
   1145     // what we want so instead we pull the pages into memory by loading
   1146     // the DLL and touching pages at a stride.
   1147     HMODULE dll_module = ::LoadLibraryExW(
   1148         file_path,
   1149         NULL,
   1150         LOAD_WITH_ALTERED_SEARCH_PATH | DONT_RESOLVE_DLL_REFERENCES);
   1151 
   1152     if (!dll_module)
   1153       return false;
   1154 
   1155     base::win::PEImage pe_image(dll_module);
   1156     PIMAGE_NT_HEADERS nt_headers = pe_image.GetNTHeaders();
   1157     size_t actual_size_to_read = size_to_read ? size_to_read :
   1158                                  nt_headers->OptionalHeader.SizeOfImage;
   1159     volatile uint8* touch = reinterpret_cast<uint8*>(dll_module);
   1160     size_t offset = 0;
   1161     while (offset < actual_size_to_read) {
   1162       uint8 unused = *(touch + offset);
   1163       offset += step_size;
   1164     }
   1165     FreeLibrary(dll_module);
   1166   }
   1167 
   1168   return true;
   1169 }
   1170 
   1171 }  // namespace file_util
   1172