Add base to the repository.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@8 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 852 insertions, 0 deletions

diff --git a/base/file_util.cc b/base/file_util.cc
new file mode 100644
index 0000000..83cf534
--- /dev/null
+++ b/base/file_util.cc
@@ -0,0 +1,852 @@
+// Copyright 2008, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "base/file_util.h"
+
+#include <windows.h>
+#include <shellapi.h>
+#include <shlobj.h>
+#include <time.h>
+#include <fstream>
+#include <string>
+
+#include "base/logging.h"
+#include "base/scoped_handle.h"
+#include "base/string_util.h"
+#include "base/win_util.h"
+#include "unicode/uniset.h"
+
+using std::wstring;
+
+namespace file_util {
+
+const wchar_t kPathSeparator = L'\\';
+const wchar_t kExtensionSeparator = L'.';
+
+bool EndsWithSeparator(std::wstring* path) {
+  return (!path->empty() && (*path)[path->length() - 1] == kPathSeparator);
+}
+
+void TrimTrailingSeparator(std::wstring* dir) {
+  while (EndsWithSeparator(dir))
+    dir->resize(dir->length() - 1);
+}
+
+void UpOneDirectory(std::wstring* dir) {
+  TrimTrailingSeparator(dir);
+
+  wstring::size_type last_sep = dir->find_last_of(kPathSeparator);
+  if (last_sep != wstring::npos)
+    dir->resize(last_sep);
+}
+
+void UpOneDirectoryOrEmpty(std::wstring* dir) {
+  TrimTrailingSeparator(dir);
+
+  wstring::size_type last_sep = dir->find_last_of(kPathSeparator);
+  if (last_sep != wstring::npos)
+    dir->resize(last_sep);
+  else
+    dir->clear();
+}
+
+void TrimFilename(std::wstring* path) {
+  if (EndsWithSeparator(path)) {
+    TrimTrailingSeparator(path);
+  } else {
+    wstring::size_type last_sep = path->find_last_of(kPathSeparator);
+    if (last_sep != wstring::npos)
+      path->resize(last_sep);
+  }
+}
+
+// TODO(mpcomplete): Make this platform-independent, etc.
+wstring GetFilenameFromPath(const wstring& path) {
+  wstring::size_type pos = path.find_last_of(L"\\/");
+  return wstring(path, pos == wstring::npos ? 0 : pos+1);
+}
+
+wstring GetFileExtensionFromPath(const wstring& path) {
+  wstring file_name = GetFilenameFromPath(path);
+  wstring::size_type last_dot = file_name.rfind(L'.');
+  return wstring(last_dot == wstring::npos? L"" : file_name, last_dot+1);
+}
+
+void AppendToPath(std::wstring* path, const std::wstring& new_ending) {
+  if (!path) {
+    NOTREACHED();
+    return;  // Don't crash in this function in release builds.
+  }
+
+  if (!EndsWithSeparator(path))
+    path->push_back(kPathSeparator);
+  path->append(new_ending);
+}
+
+void InsertBeforeExtension(std::wstring* path, const std::wstring& suffix) {
+  DCHECK(path);
+
+  const wstring::size_type last_dot = path->rfind(kExtensionSeparator);
+  const wstring::size_type last_sep = path->rfind(kPathSeparator);
+
+  if (last_dot == wstring::npos ||
+      (last_sep != wstring::npos && last_dot < last_sep)) {
+    // The path looks something like "C:\pics.old\jojo" or "C:\pics\jojo".
+    // We should just append the suffix to the entire path.
+    path->append(suffix);
+    return;
+  }
+
+  path->insert(last_dot, suffix);
+}
+
+void ReplaceIllegalCharacters(std::wstring* file_name, int replace_char) {
+  DCHECK(file_name);
+
+  // Control characters, formating characters, non-characters, and
+  // some printable ASCII characters regarded as dangerous ('"*/:<>?\\').
+  // See  http://blogs.msdn.com/michkap/archive/2006/11/03/941420.aspx
+  // and http://msdn2.microsoft.com/en-us/library/Aa365247.aspx
+  // TODO(jungshik): Revisit the set. ZWJ and ZWNJ are excluded because they
+  // are legitimate in Arabic and some S/SE Asian scripts. However, when used
+  // elsewhere, they can be confusing/problematic.
+  // Also, consider wrapping the set with our Singleton class to create and
+  // freeze it only once. Note that there's a trade-off between memory and
+  // speed.
+
+  UErrorCode status = U_ZERO_ERROR;
+#ifdef U_WCHAR_IS_UTF16
+  UnicodeSet illegal_characters(UnicodeString(
+      L"[[\"*/:<>?\\\\|][:Cc:][:Cf:] - [\u200c\u200d]]"), status);
+#else
+  UnicodeSet illegal_characters(UNICODE_STRING_SIMPLE(
+      "[[\"*/:<>?\\\\|][:Cc:][:Cf:] - [\\u200c\\u200d]]").unescape(), status);
+#endif
+  DCHECK(U_SUCCESS(status));
+  // Add non-characters. If this becomes a performance bottleneck by
+  // any chance, check |ucs4 & 0xFFFEu == 0xFFFEu|, instead.
+  illegal_characters.add(0xFDD0, 0xFDEF);
+  for (int i = 0; i <= 0x10; ++i) {
+    int plane_base = 0x10000 * i;
+    illegal_characters.add(plane_base + 0xFFFE, plane_base + 0xFFFF);
+  }
+  illegal_characters.freeze();
+  DCHECK(!illegal_characters.contains(replace_char) && replace_char < 0x10000);
+
+  // Remove leading and trailing whitespace.
+  TrimWhitespace(*file_name, TRIM_ALL, file_name);
+
+  std::wstring::size_type i = 0;
+  std::wstring::size_type length = file_name->size();
+#ifdef U_WCHAR_IS_UTF16
+  // Using |span| method of UnicodeSet might speed things up a bit, but
+  // it's not likely to matter here.
+  const wchar_t* wstr = file_name->data();
+  std::wstring temp;
+  temp.reserve(length);
+  while (i < length) {
+    UChar32 ucs4;
+    std::wstring::size_type prev = i;
+    U16_NEXT(wstr, i, length, ucs4);
+    if (illegal_characters.contains(ucs4)) {
+      temp.push_back(replace_char);
+    } else if (ucs4 < 0x10000) {
+      temp.push_back(ucs4);
+    } else {
+      temp.push_back(wstr[prev]);
+      temp.push_back(wstr[prev + 1]);
+    }
+  }
+  file_name->swap(temp);
+#elif defined(U_WCHAR_IS_UTF32)
+  while (i < length) {
+    if (illegal_characters.contains(wstr[i])) {
+      *file_name[i] = replace_char;
+    }
+  }
+#else
+#error wchar_t* should be either UTF-16 or UTF-32
+#endif
+}
+
+void ReplaceExtension(std::wstring* file_name, const std::wstring& extension) {
+  const wstring::size_type last_dot = file_name->rfind(L'.');
+  wstring result = file_name->substr(0, last_dot);
+  if (!extension.empty() && extension != L".") {
+    if (extension.at(0) != L'.')
+      result.append(L".");
+    result.append(extension);
+  }
+  file_name->swap(result);
+}
+
+wstring GetDirectoryFromPath(const std::wstring& path) {
+  wchar_t path_buffer[MAX_PATH];
+  wchar_t* file_ptr = NULL;
+  if (GetFullPathName(path.c_str(), MAX_PATH, path_buffer, &file_ptr) == 0)
+    return L"";
+
+  wstring::size_type nc = file_ptr ? file_ptr - path_buffer : path.length();
+  wstring directory(path, 0, nc);
+  TrimTrailingSeparator(&directory);
+  return directory;
+}
+
+int CountFilesCreatedAfter(const std::wstring& path,
+                           const FILETIME& comparison_time) {
+  int file_count = 0;
+
+  WIN32_FIND_DATA find_file_data;
+  std::wstring filename_spec = path + L"\\*";  // All files in given dir
+  HANDLE find_handle = FindFirstFile(filename_spec.c_str(), &find_file_data);
+  if (find_handle != INVALID_HANDLE_VALUE) {
+    do {
+      // Don't count current or parent directories.
+      if ((wcscmp(find_file_data.cFileName, L"..") == 0) ||
+          (wcscmp(find_file_data.cFileName, L".") == 0))
+        continue;
+
+      long result = CompareFileTime(&find_file_data.ftCreationTime,
+                                    &comparison_time);
+      // File was created after or on comparison time
+      if ((result == 1) || (result == 0))
+        ++file_count;
+    } while (FindNextFile(find_handle,  &find_file_data));
+    FindClose(find_handle);
+  }
+
+  return file_count;
+}
+
+bool Delete(const std::wstring& path, bool recursive) {
+  if (path.length() >= MAX_PATH)
+    return false;
+
+  // If we're not recursing use DeleteFile; it should be faster. DeleteFile
+  // fails if passed a directory though, which is why we fall through on
+  // failure to the SHFileOperation.
+  if (!recursive && DeleteFile(path.c_str()) != 0)
+    return true;
+
+  // SHFILEOPSTRUCT wants the path to be terminated with two NULLs,
+  // so we have to use wcscpy because wcscpy_s writes non-NULLs
+  // into the rest of the buffer.
+  wchar_t double_terminated_path[MAX_PATH + 1] = {0};
+#pragma warning(suppress:4996)  // don't complain about wcscpy deprecation
+  wcscpy(double_terminated_path, path.c_str());
+
+  SHFILEOPSTRUCT file_operation = {0};
+  file_operation.wFunc = FO_DELETE;
+  file_operation.pFrom = double_terminated_path;
+  file_operation.fFlags = FOF_NOERRORUI | FOF_SILENT | FOF_NOCONFIRMATION;
+  if (!recursive)
+    file_operation.fFlags |= FOF_NORECURSION | FOF_FILESONLY;
+  return (SHFileOperation(&file_operation) == 0);
+}
+
+bool Move(const std::wstring& from_path, const std::wstring& to_path) {
+  // NOTE: I suspect we could support longer paths, but that would involve
+  // analyzing all our usage of files.
+  if (from_path.length() >= MAX_PATH || to_path.length() >= MAX_PATH)
+    return false;
+  return (MoveFileEx(from_path.c_str(), to_path.c_str(),
+                     MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING) != 0);
+}
+
+bool CopyFile(const std::wstring& from_path, const std::wstring& to_path) {
+  // NOTE: I suspect we could support longer paths, but that would involve
+  // analyzing all our usage of files.
+  if (from_path.length() >= MAX_PATH || to_path.length() >= MAX_PATH)
+    return false;
+  return (::CopyFile(from_path.c_str(), to_path.c_str(), false) != 0);
+}
+
+bool ShellCopy(const std::wstring& from_path, const std::wstring& to_path,
+               bool recursive) {
+  // NOTE: I suspect we could support longer paths, but that would involve
+  // analyzing all our usage of files.
+  if (from_path.length() >= MAX_PATH || to_path.length() >= MAX_PATH)
+    return false;
+
+  // SHFILEOPSTRUCT wants the path to be terminated with two NULLs,
+  // so we have to use wcscpy because wcscpy_s writes non-NULLs
+  // into the rest of the buffer.
+  wchar_t double_terminated_path_from[MAX_PATH + 1] = {0};
+  wchar_t double_terminated_path_to[MAX_PATH + 1] = {0};
+#pragma warning(suppress:4996)  // don't complain about wcscpy deprecation
+  wcscpy(double_terminated_path_from, from_path.c_str());
+#pragma warning(suppress:4996)  // don't complain about wcscpy deprecation
+  wcscpy(double_terminated_path_to, to_path.c_str());
+
+  SHFILEOPSTRUCT file_operation = {0};
+  file_operation.wFunc = FO_COPY;
+  file_operation.pFrom = double_terminated_path_from;
+  file_operation.pTo = double_terminated_path_to;
+  file_operation.fFlags = FOF_NOERRORUI | FOF_SILENT | FOF_NOCONFIRMATION |
+                          FOF_NOCONFIRMMKDIR;
+  if (!recursive)
+    file_operation.fFlags |= FOF_NORECURSION | FOF_FILESONLY;
+
+  return (SHFileOperation(&file_operation) == 0);
+}
+
+bool CopyDirectory(const std::wstring& from_path, const std::wstring& to_path,
+                   bool recursive) {
+  if (recursive)
+    return ShellCopy(from_path, to_path, true);
+
+  // Instead of creating a new directory, we copy the old one to include the
+  // security information of the folder as part of the copy.
+  if (!PathExists(to_path)) {
+    // Except that Vista fails to do that, and instead do a recursive copy if
+    // the target directory doesn't exist.
+    if (win_util::GetWinVersion() >= win_util::WINVERSION_VISTA)
+      CreateDirectory(to_path);
+    else
+      ShellCopy(from_path, to_path, false);
+  }
+
+  std::wstring directory(from_path);
+  AppendToPath(&directory, L"*.*");
+  return ShellCopy(directory, to_path, false);
+}
+
+bool PathExists(const std::wstring& path) {
+  return (GetFileAttributes(path.c_str()) != INVALID_FILE_ATTRIBUTES);
+}
+
+bool PathIsWritable(const std::wstring& path) {
+  HANDLE dir =
+      CreateFile(path.c_str(), FILE_ADD_FILE,
+                 FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+                 NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+
+  if (dir == INVALID_HANDLE_VALUE)
+    return false;
+
+  CloseHandle(dir);
+  return true;
+}
+
+bool GetFileCreationLocalTimeFromHandle(HANDLE file_handle,
+                                        LPSYSTEMTIME creation_time) {
+  if (!file_handle)
+    return false;
+
+  FILETIME utc_filetime;
+  if (!GetFileTime(file_handle, &utc_filetime, NULL, NULL))
+    return false;
+
+  FILETIME local_filetime;
+  if (!FileTimeToLocalFileTime(&utc_filetime, &local_filetime))
+    return false;
+
+  return !!FileTimeToSystemTime(&local_filetime, creation_time);
+}
+
+bool GetFileCreationLocalTime(const std::wstring& filename,
+                              LPSYSTEMTIME creation_time) {
+  ScopedHandle file_handle(
+      CreateFile(filename.c_str(), GENERIC_READ,
+                 FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+                 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL));
+  return GetFileCreationLocalTimeFromHandle(file_handle.Get(), creation_time);
+}
+
+bool ContentsEqual(const std::wstring& filename1,
+                   const std::wstring& filename2) {
+  // We open the file in binary format even if they are text files because
+  // we are just comparing that bytes are exactly same in both files and not
+  // doing anything smart with text formatting.
+  std::ifstream file1(filename1.c_str(), std::ios::in | std::ios::binary);
+  std::ifstream file2(filename2.c_str(), std::ios::in | std::ios::binary);
+
+  // Even if both files aren't openable (and thus, in some sense, "equal"),
+  // any unusable file yields a result of "false".
+  if (!file1.is_open() || !file2.is_open())
+    return false;
+
+  const int BUFFER_SIZE = 2056;
+  char buffer1[BUFFER_SIZE], buffer2[BUFFER_SIZE];
+  do {
+    file1.read(buffer1, BUFFER_SIZE);
+    file2.read(buffer2, BUFFER_SIZE);
+
+    if ((file1.eof() && !file2.eof()) ||
+        (!file1.eof() && file2.eof()) ||
+        (file1.gcount() != file2.gcount()) ||
+        (memcmp(buffer1, buffer2, file1.gcount()))) {
+      file1.close();
+      file2.close();
+      return false;
+    }
+  } while (!file1.eof() && !file2.eof());
+
+  file1.close();
+  file2.close();
+  return true;
+}
+
+bool ReadFileToString(const std::wstring& path, std::string* contents) {
+  FILE* file;
+  errno_t err = _wfopen_s(&file, path.c_str(), L"rbS");
+  if (err != 0)
+    return false;
+
+  char buf[1 << 16];
+  size_t len;
+  while ((len = fread(buf, 1, sizeof(buf), file)) > 0) {
+    contents->append(buf, len);
+  }
+  fclose(file);
+
+  return true;
+}
+
+bool ResolveShortcut(std::wstring* path) {
+  HRESULT result;
+  IShellLink *shell = NULL;
+  bool is_resolved = false;
+
+  // Get pointer to the IShellLink interface
+  result = CoCreateInstance(CLSID_ShellLink, NULL,
+                            CLSCTX_INPROC_SERVER, IID_IShellLink,
+                            reinterpret_cast<LPVOID*>(&shell));
+  if (SUCCEEDED(result)) {
+    IPersistFile *persist = NULL;
+    // Query IShellLink for the IPersistFile interface
+    result = shell->QueryInterface(IID_IPersistFile,
+                                   reinterpret_cast<LPVOID*>(&persist));
+    if (SUCCEEDED(result)) {
+      WCHAR temp_path[MAX_PATH];
+      // Load the shell link
+      result = persist->Load(path->c_str(), STGM_READ);
+      if (SUCCEEDED(result)) {
+        // Try to find the target of a shortcut
+        result = shell->Resolve(0, SLR_NO_UI);
+        if (SUCCEEDED(result)) {
+          result = shell->GetPath(temp_path, MAX_PATH,
+                                  NULL, SLGP_UNCPRIORITY);
+          *path = temp_path;
+          is_resolved = true;
+        }
+      }
+    }
+    if (persist)
+      persist->Release();
+  }
+  if (shell)
+    shell->Release();
+
+  return is_resolved;
+}
+
+bool CreateShortcutLink(const wchar_t *source, const wchar_t *destination,
+                        const wchar_t *working_dir, const wchar_t *arguments,
+                        const wchar_t *description, const wchar_t *icon,
+                        int icon_index) {
+  IShellLink *i_shell_link = NULL;
+  IPersistFile *i_persist_file = NULL;
+
+  // Get pointer to the IShellLink interface
+  HRESULT result = CoCreateInstance(CLSID_ShellLink, NULL,
+                                    CLSCTX_INPROC_SERVER, IID_IShellLink,
+                                    reinterpret_cast<LPVOID*>(&i_shell_link));
+  if (FAILED(result))
+    return false;
+
+  // Query IShellLink for the IPersistFile interface
+  result = i_shell_link->QueryInterface(IID_IPersistFile,
+      reinterpret_cast<LPVOID*>(&i_persist_file));
+  if (FAILED(result)) {
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (FAILED(i_shell_link->SetPath(source))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (working_dir && FAILED(i_shell_link->SetWorkingDirectory(working_dir))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (arguments && FAILED(i_shell_link->SetArguments(arguments))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (description && FAILED(i_shell_link->SetDescription(description))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (icon && FAILED(i_shell_link->SetIconLocation(icon, icon_index))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  result = i_persist_file->Save(destination, TRUE);
+  i_persist_file->Release();
+  i_shell_link->Release();
+  return SUCCEEDED(result);
+}
+
+
+bool UpdateShortcutLink(const wchar_t *source, const wchar_t *destination,
+                        const wchar_t *working_dir, const wchar_t *arguments,
+                        const wchar_t *description, const wchar_t *icon,
+                        int icon_index) {
+  // Get pointer to the IPersistFile interface and load existing link
+  IShellLink *i_shell_link = NULL;
+  if (FAILED(CoCreateInstance(CLSID_ShellLink, NULL,
+                              CLSCTX_INPROC_SERVER, IID_IShellLink,
+                              reinterpret_cast<LPVOID*>(&i_shell_link))))
+    return false;
+
+  IPersistFile *i_persist_file = NULL;
+  if (FAILED(i_shell_link->QueryInterface(
+      IID_IPersistFile, reinterpret_cast<LPVOID*>(&i_persist_file)))) {
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (FAILED(i_persist_file->Load(destination, 0))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (source && FAILED(i_shell_link->SetPath(source))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (working_dir && FAILED(i_shell_link->SetWorkingDirectory(working_dir))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (arguments && FAILED(i_shell_link->SetArguments(arguments))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (description && FAILED(i_shell_link->SetDescription(description))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  if (icon && FAILED(i_shell_link->SetIconLocation(icon, icon_index))) {
+    i_persist_file->Release();
+    i_shell_link->Release();
+    return false;
+  }
+
+  HRESULT result = i_persist_file->Save(destination, TRUE);
+  i_persist_file->Release();
+  i_shell_link->Release();
+  return SUCCEEDED(result);
+}
+
+bool GetTempDir(std::wstring* path) {
+  wchar_t temp_path[MAX_PATH + 1];
+  DWORD path_len = ::GetTempPath(MAX_PATH, temp_path);
+  if (path_len >= MAX_PATH || path_len <= 0)
+    return false;
+  path->assign(temp_path);
+  TrimTrailingSeparator(path);
+  return true;
+}
+
+bool CreateTemporaryFileName(std::wstring* temp_file) {
+  wchar_t temp_name[MAX_PATH + 1];
+  std::wstring temp_path;
+
+  if (!GetTempDir(&temp_path))
+    return false;
+
+  if (!GetTempFileName(temp_path.c_str(), L"", 0, temp_name))
+    return false;  // fail!
+
+  DWORD path_len = GetLongPathName(temp_name, temp_name, MAX_PATH);
+  if (path_len > MAX_PATH + 1 || path_len == 0)
+    return false;  // fail!
+
+  temp_file->assign(temp_name, path_len);
+  return true;
+}
+
+bool CreateNewTempDirectory(const std::wstring& prefix,
+                            std::wstring* new_temp_path) {
+  std::wstring system_temp_dir;
+  if (!GetTempDir(&system_temp_dir))
+    return false;
+
+  std::wstring path_to_create;
+  srand(static_cast<uint32>(time(NULL)));
+
+  int count = 0;
+  while (count < 50) {
+    // Try create a new temporary directory with random generated name. If
+    // the one exists, keep trying another path name until we reach some limit.
+    path_to_create.assign(system_temp_dir);
+    std::wstring new_dir_name;
+    new_dir_name.assign(prefix);
+    new_dir_name.append(IntToWString(rand() % kint16max));
+    file_util::AppendToPath(&path_to_create, new_dir_name);
+
+    if (::CreateDirectory(path_to_create.c_str(), NULL))
+      break;
+    count++;
+  }
+
+  if (count == 50) {
+    return false;
+  }
+
+  new_temp_path->assign(path_to_create);
+  return true;
+}
+
+bool CreateDirectory(const std::wstring& full_path) {
+  int err = SHCreateDirectoryEx(NULL, full_path.c_str(), NULL);
+  return err == ERROR_SUCCESS;
+}
+
+bool GetFileSize(const std::wstring& file_path, int64* file_size) {
+  ScopedHandle file_handle(
+      CreateFile(file_path.c_str(), GENERIC_READ,
+                 FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL,
+                 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL));
+
+  LARGE_INTEGER win32_file_size = {0};
+  if (!GetFileSizeEx(file_handle, &win32_file_size)) {
+    return false;
+  }
+
+  *file_size = win32_file_size.QuadPart;
+  return true;
+}
+
+int ReadFile(const std::wstring& filename, char* data, int size) {
+  ScopedHandle file(CreateFile(filename.c_str(),
+                               GENERIC_READ,
+                               FILE_SHARE_READ | FILE_SHARE_WRITE,
+                               NULL,
+                               OPEN_EXISTING,
+                               FILE_FLAG_SEQUENTIAL_SCAN,
+                               NULL));
+  if (file == INVALID_HANDLE_VALUE)
+    return -1;
+
+  int ret_value;
+  DWORD read;
+  if (::ReadFile(file, data, size, &read, NULL) && read == size) {
+    ret_value = static_cast<int>(read);
+  } else {
+    ret_value = -1;
+  }
+
+  return ret_value;
+}
+
+int WriteFile(const std::wstring& filename, const char* data, int size) {
+  ScopedHandle file(CreateFile(filename.c_str(),
+                               GENERIC_WRITE,
+                               0,
+                               NULL,
+                               CREATE_ALWAYS,
+                               0,
+                               NULL));
+  if (file == INVALID_HANDLE_VALUE)
+    return -1;
+
+  int ret_value;
+  DWORD written;
+  if (::WriteFile(file, data, size, &written, NULL)  && written == size) {
+    ret_value = static_cast<int>(written);
+  } else {
+    ret_value = -1;
+  }
+
+  return ret_value;
+}
+
+FileEnumerator::FileEnumerator(const std::wstring& root_path,
+                               bool recursive,
+                               FileEnumerator::FILE_TYPE file_type)
+    : recursive_(recursive),
+      file_type_(file_type),
+      is_in_find_op_(false),
+      find_handle_(INVALID_HANDLE_VALUE) {
+  pending_paths_.push(root_path);
+}
+
+FileEnumerator::FileEnumerator(const std::wstring& root_path,
+                               bool recursive,
+                               FileEnumerator::FILE_TYPE file_type,
+                               const std::wstring& pattern)
+    : recursive_(recursive),
+      file_type_(file_type),
+      is_in_find_op_(false),
+      pattern_(pattern),
+      find_handle_(INVALID_HANDLE_VALUE) {
+  pending_paths_.push(root_path);
+}
+
+FileEnumerator::~FileEnumerator() {
+  if (find_handle_ != INVALID_HANDLE_VALUE)
+    FindClose(find_handle_);
+}
+
+std::wstring FileEnumerator::Next() {
+  if (!is_in_find_op_) {
+    if (pending_paths_.empty())
+      return std::wstring();
+
+    // The last find FindFirstFile operation is done, prepare a new one.
+    // root_path_ must have the trailing directory character.
+    root_path_ = pending_paths_.top();
+    file_util::AppendToPath(&root_path_, std::wstring());
+    pending_paths_.pop();
+
+    // Start a new find operation.
+    std::wstring src(root_path_);
+
+    if (pattern_.empty())
+      file_util::AppendToPath(&src, L"*");  // No pattern = match everything.
+    else
+      file_util::AppendToPath(&src, pattern_);
+
+    find_handle_ = FindFirstFile(src.c_str(), &find_data_);
+    is_in_find_op_ = true;
+
+  } else {
+    // Search for the next file/directory.
+    if (!FindNextFile(find_handle_, &find_data_)) {
+      FindClose(find_handle_);
+      find_handle_ = INVALID_HANDLE_VALUE;
+    }
+  }
+
+  if (INVALID_HANDLE_VALUE == find_handle_) {
+    is_in_find_op_ = false;
+
+    // This is reached when we have finished a directory and are advancing to
+    // the next one in the queue. We applied the pattern (if any) to the files
+    // in the root search directory, but for those directories which were
+    // matched, we want to enumerate all files inside them. This will happen
+    // when the handle is empty.
+    pattern_.clear();
+
+    return Next();
+  }
+
+  std::wstring cur_file(find_data_.cFileName);
+  // Skip over . and ..
+  if (L"." == cur_file || L".." == cur_file)
+    return Next();
+
+  // Construct the absolute filename.
+  cur_file.insert(0, root_path_);
+
+  if (find_data_.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
+    if (recursive_) {
+      // If |cur_file| is a directory, and we are doing recursive searching, add
+      // it to pending_paths_ so we scan it after we finish scanning this
+      // directory.
+      pending_paths_.push(cur_file);
+      return (file_type_ & FileEnumerator::DIRECTORIES) ? cur_file : Next();
+    }
+
+    if ((file_type_ & FileEnumerator::DIRECTORIES) == 0)
+      return Next();
+  }
+  return (file_type_ & FileEnumerator::FILES) ? cur_file : Next();
+}
+
+bool RenameFileAndResetSecurityDescriptor(
+    const std::wstring& source_file_path,
+    const std::wstring& target_file_path) {
+  // The MoveFile API does not reset the security descriptor on the target
+  // file. To ensure that the target file gets the correct security descriptor
+  // we create the target file initially in the target path, read its security
+  // descriptor and stamp this descriptor on the target file after the MoveFile
+  // API completes.
+  ScopedHandle temp_file_handle_for_security_desc(
+      CreateFileW(target_file_path.c_str(), GENERIC_READ | GENERIC_WRITE,
+                  FILE_SHARE_READ, NULL, OPEN_ALWAYS,
+                  FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE,
+                  NULL));
+  if (!temp_file_handle_for_security_desc.IsValid())
+    return false;
+
+  // Check how much we should allocate for the security descriptor.
+  unsigned long security_descriptor_size_in_bytes = 0;
+  GetFileSecurity(target_file_path.c_str(), DACL_SECURITY_INFORMATION, NULL, 0,
+                  &security_descriptor_size_in_bytes);
+  if (ERROR_INSUFFICIENT_BUFFER != GetLastError() ||
+      security_descriptor_size_in_bytes == 0)
+    return false;
+
+  scoped_array<char> security_descriptor(
+      new char[security_descriptor_size_in_bytes]);
+
+  if (!GetFileSecurity(target_file_path.c_str(), DACL_SECURITY_INFORMATION,
+                       security_descriptor.get(),
+                       security_descriptor_size_in_bytes,
+                       &security_descriptor_size_in_bytes)) {
+    return false;
+  }
+
+  temp_file_handle_for_security_desc.Set(INVALID_HANDLE_VALUE);
+
+  if (!MoveFileEx(source_file_path.c_str(), target_file_path.c_str(),
+                  MOVEFILE_COPY_ALLOWED)) {
+    return false;
+  }
+
+  return !!SetFileSecurity(target_file_path.c_str(),
+                           DACL_SECURITY_INFORMATION,
+                           security_descriptor.get());
+}
+
+}  // namespace