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- // Copyright (c) 2012 The Chromium Authors. All rights reserved.
- // Use of this source code is governed by a BSD-style license that can be
- // found in the LICENSE file.
- #include "base/files/file_util.h"
- #include <windows.h>
- #include <io.h>
- #include <psapi.h>
- #include <shellapi.h>
- #include <shlobj.h>
- #include <stddef.h>
- #include <stdint.h>
- #include <time.h>
- #include <winsock2.h>
- #include <algorithm>
- #include <limits>
- #include <string>
- #include <utility>
- #include "base/bind.h"
- #include "base/callback.h"
- #include "base/debug/alias.h"
- #include "base/files/file_enumerator.h"
- #include "base/files/file_path.h"
- #include "base/files/memory_mapped_file.h"
- #include "base/guid.h"
- #include "base/location.h"
- #include "base/logging.h"
- #include "base/metrics/histogram_functions.h"
- #include "base/numerics/safe_conversions.h"
- #include "base/process/process_handle.h"
- #include "base/rand_util.h"
- #include "base/strings/strcat.h"
- #include "base/strings/string_number_conversions.h"
- #include "base/strings/string_piece.h"
- #include "base/strings/string_util.h"
- #include "base/strings/string_util_win.h"
- #include "base/strings/utf_string_conversions.h"
- #include "base/task/bind_post_task.h"
- #include "base/task/sequenced_task_runner.h"
- #include "base/task/thread_pool.h"
- #include "base/threading/scoped_blocking_call.h"
- #include "base/threading/scoped_thread_priority.h"
- #include "base/threading/sequenced_task_runner_handle.h"
- #include "base/time/time.h"
- #include "base/win/scoped_handle.h"
- #include "base/win/windows_types.h"
- #include "base/win/windows_version.h"
- namespace base {
- namespace {
- const DWORD kFileShareAll =
- FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
- // Returns the Win32 last error code or ERROR_SUCCESS if the last error code is
- // ERROR_FILE_NOT_FOUND or ERROR_PATH_NOT_FOUND. This is useful in cases where
- // the absence of a file or path is a success condition (e.g., when attempting
- // to delete an item in the filesystem).
- DWORD ReturnLastErrorOrSuccessOnNotFound() {
- const DWORD error_code = ::GetLastError();
- return (error_code == ERROR_FILE_NOT_FOUND ||
- error_code == ERROR_PATH_NOT_FOUND)
- ? ERROR_SUCCESS
- : error_code;
- }
- // Deletes all files and directories in a path.
- // Returns ERROR_SUCCESS on success or the Windows error code corresponding to
- // the first error encountered. ERROR_FILE_NOT_FOUND and ERROR_PATH_NOT_FOUND
- // are considered success conditions, and are therefore never returned.
- DWORD DeleteFileRecursive(const FilePath& path,
- const FilePath::StringType& pattern,
- bool recursive) {
- FileEnumerator traversal(path, false,
- FileEnumerator::FILES | FileEnumerator::DIRECTORIES,
- pattern);
- DWORD result = ERROR_SUCCESS;
- for (FilePath current = traversal.Next(); !current.empty();
- current = traversal.Next()) {
- // Try to clear the read-only bit if we find it.
- FileEnumerator::FileInfo info = traversal.GetInfo();
- if ((info.find_data().dwFileAttributes & FILE_ATTRIBUTE_READONLY) &&
- (recursive || !info.IsDirectory())) {
- ::SetFileAttributes(
- current.value().c_str(),
- info.find_data().dwFileAttributes & ~DWORD{FILE_ATTRIBUTE_READONLY});
- }
- DWORD this_result = ERROR_SUCCESS;
- if (info.IsDirectory()) {
- if (recursive) {
- this_result = DeleteFileRecursive(current, pattern, true);
- DCHECK_NE(static_cast<LONG>(this_result), ERROR_FILE_NOT_FOUND);
- DCHECK_NE(static_cast<LONG>(this_result), ERROR_PATH_NOT_FOUND);
- if (this_result == ERROR_SUCCESS &&
- !::RemoveDirectory(current.value().c_str())) {
- this_result = ReturnLastErrorOrSuccessOnNotFound();
- }
- }
- } else if (!::DeleteFile(current.value().c_str())) {
- this_result = ReturnLastErrorOrSuccessOnNotFound();
- }
- if (result == ERROR_SUCCESS)
- result = this_result;
- }
- return result;
- }
- // Appends |mode_char| to |mode| before the optional character set encoding; see
- // https://msdn.microsoft.com/library/yeby3zcb.aspx for details.
- void AppendModeCharacter(wchar_t mode_char, std::wstring* mode) {
- size_t comma_pos = mode->find(L',');
- mode->insert(comma_pos == std::wstring::npos ? mode->length() : comma_pos, 1,
- mode_char);
- }
- bool DoCopyFile(const FilePath& from_path,
- const FilePath& to_path,
- bool fail_if_exists) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- if (from_path.ReferencesParent() || to_path.ReferencesParent())
- return false;
- // NOTE: I suspect we could support longer paths, but that would involve
- // analyzing all our usage of files.
- if (from_path.value().length() >= MAX_PATH ||
- to_path.value().length() >= MAX_PATH) {
- return false;
- }
- // Mitigate the issues caused by loading DLLs on a background thread
- // (http://crbug/973868).
- SCOPED_MAY_LOAD_LIBRARY_AT_BACKGROUND_PRIORITY();
- // Unlike the posix implementation that copies the file manually and discards
- // the ACL bits, CopyFile() copies the complete SECURITY_DESCRIPTOR and access
- // bits, which is usually not what we want. We can't do much about the
- // SECURITY_DESCRIPTOR but at least remove the read only bit.
- const wchar_t* dest = to_path.value().c_str();
- if (!::CopyFile(from_path.value().c_str(), dest, fail_if_exists)) {
- // Copy failed.
- return false;
- }
- DWORD attrs = GetFileAttributes(dest);
- if (attrs == INVALID_FILE_ATTRIBUTES) {
- return false;
- }
- if (attrs & FILE_ATTRIBUTE_READONLY) {
- SetFileAttributes(dest, attrs & ~DWORD{FILE_ATTRIBUTE_READONLY});
- }
- return true;
- }
- bool DoCopyDirectory(const FilePath& from_path,
- const FilePath& to_path,
- bool recursive,
- bool fail_if_exists) {
- // NOTE(maruel): Previous version of this function used to call
- // SHFileOperation(). This used to copy the file attributes and extended
- // attributes, OLE structured storage, NTFS file system alternate data
- // streams, SECURITY_DESCRIPTOR. In practice, this is not what we want, we
- // want the containing directory to propagate its SECURITY_DESCRIPTOR.
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- // NOTE: I suspect we could support longer paths, but that would involve
- // analyzing all our usage of files.
- if (from_path.value().length() >= MAX_PATH ||
- to_path.value().length() >= MAX_PATH) {
- return false;
- }
- // This function does not properly handle destinations within the source.
- FilePath real_to_path = to_path;
- if (PathExists(real_to_path)) {
- real_to_path = MakeAbsoluteFilePath(real_to_path);
- if (real_to_path.empty())
- return false;
- } else {
- real_to_path = MakeAbsoluteFilePath(real_to_path.DirName());
- if (real_to_path.empty())
- return false;
- }
- FilePath real_from_path = MakeAbsoluteFilePath(from_path);
- if (real_from_path.empty())
- return false;
- if (real_to_path == real_from_path || real_from_path.IsParent(real_to_path))
- return false;
- int traverse_type = FileEnumerator::FILES;
- if (recursive)
- traverse_type |= FileEnumerator::DIRECTORIES;
- FileEnumerator traversal(from_path, recursive, traverse_type);
- if (!PathExists(from_path)) {
- DLOG(ERROR) << "CopyDirectory() couldn't stat source directory: "
- << from_path.value().c_str();
- return false;
- }
- // TODO(maruel): This is not necessary anymore.
- DCHECK(recursive || DirectoryExists(from_path));
- FilePath current = from_path;
- bool from_is_dir = DirectoryExists(from_path);
- bool success = true;
- FilePath from_path_base = from_path;
- if (recursive && DirectoryExists(to_path)) {
- // If the destination already exists and is a directory, then the
- // top level of source needs to be copied.
- from_path_base = from_path.DirName();
- }
- while (success && !current.empty()) {
- // current is the source path, including from_path, so append
- // the suffix after from_path to to_path to create the target_path.
- FilePath target_path(to_path);
- if (from_path_base != current) {
- if (!from_path_base.AppendRelativePath(current, &target_path)) {
- success = false;
- break;
- }
- }
- if (from_is_dir) {
- if (!DirectoryExists(target_path) &&
- !::CreateDirectory(target_path.value().c_str(), NULL)) {
- DLOG(ERROR) << "CopyDirectory() couldn't create directory: "
- << target_path.value().c_str();
- success = false;
- }
- } else if (!DoCopyFile(current, target_path, fail_if_exists)) {
- DLOG(ERROR) << "CopyDirectory() couldn't create file: "
- << target_path.value().c_str();
- success = false;
- }
- current = traversal.Next();
- if (!current.empty())
- from_is_dir = traversal.GetInfo().IsDirectory();
- }
- return success;
- }
- // Returns ERROR_SUCCESS on success, or a Windows error code on failure.
- DWORD DoDeleteFile(const FilePath& path, bool recursive) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- if (path.empty())
- return ERROR_SUCCESS;
- if (path.value().length() >= MAX_PATH)
- return ERROR_BAD_PATHNAME;
- // Handle any path with wildcards.
- if (path.BaseName().value().find_first_of(FILE_PATH_LITERAL("*?")) !=
- FilePath::StringType::npos) {
- const DWORD error_code =
- DeleteFileRecursive(path.DirName(), path.BaseName().value(), recursive);
- DCHECK_NE(static_cast<LONG>(error_code), ERROR_FILE_NOT_FOUND);
- DCHECK_NE(static_cast<LONG>(error_code), ERROR_PATH_NOT_FOUND);
- return error_code;
- }
- // Report success if the file or path does not exist.
- const DWORD attr = ::GetFileAttributes(path.value().c_str());
- if (attr == INVALID_FILE_ATTRIBUTES)
- return ReturnLastErrorOrSuccessOnNotFound();
- // Clear the read-only bit if it is set.
- if ((attr & FILE_ATTRIBUTE_READONLY) &&
- !::SetFileAttributes(path.value().c_str(),
- attr & ~DWORD{FILE_ATTRIBUTE_READONLY})) {
- // It's possible for |path| to be gone now under a race with other deleters.
- return ReturnLastErrorOrSuccessOnNotFound();
- }
- // Perform a simple delete on anything that isn't a directory.
- if (!(attr & FILE_ATTRIBUTE_DIRECTORY)) {
- return ::DeleteFile(path.value().c_str())
- ? ERROR_SUCCESS
- : ReturnLastErrorOrSuccessOnNotFound();
- }
- if (recursive) {
- const DWORD error_code =
- DeleteFileRecursive(path, FILE_PATH_LITERAL("*"), true);
- DCHECK_NE(static_cast<LONG>(error_code), ERROR_FILE_NOT_FOUND);
- DCHECK_NE(static_cast<LONG>(error_code), ERROR_PATH_NOT_FOUND);
- if (error_code != ERROR_SUCCESS)
- return error_code;
- }
- return ::RemoveDirectory(path.value().c_str())
- ? ERROR_SUCCESS
- : ReturnLastErrorOrSuccessOnNotFound();
- }
- // Deletes the file/directory at |path| (recursively if |recursive| and |path|
- // names a directory), returning true on success. Sets the Windows last-error
- // code and returns false on failure.
- bool DeleteFileOrSetLastError(const FilePath& path, bool recursive) {
- const DWORD error = DoDeleteFile(path, recursive);
- if (error == ERROR_SUCCESS)
- return true;
- ::SetLastError(error);
- return false;
- }
- constexpr int kMaxDeleteAttempts = 9;
- void LogFileDeleteRetryCount(bool recursive, int attempt) {
- UmaHistogramExactLinear(recursive ? "Windows.PathRecursivelyDeleteRetryCount"
- : "Windows.FileDeleteRetryCount",
- attempt, kMaxDeleteAttempts);
- }
- void DeleteFileWithRetry(const FilePath& path,
- bool recursive,
- int attempt,
- OnceCallback<void(bool)> reply_callback) {
- // Retry every 250ms for up to two seconds. These values were pulled out of
- // thin air, and may be adjusted in the future based on the metrics collected.
- static constexpr TimeDelta kDeleteFileRetryDelay = Milliseconds(250);
- if (DeleteFileOrSetLastError(path, recursive)) {
- // Log how many times we had to retry the RetryDeleteFile operation before
- // it succeeded. This will be from 0 to kMaxDeleteAttempts - 1.
- LogFileDeleteRetryCount(recursive, attempt);
- // Consider introducing further retries until the item has been removed from
- // the filesystem and its name is ready for reuse; see the comments in
- // chrome/installer/mini_installer/delete_with_retry.cc for details.
- if (!reply_callback.is_null())
- std::move(reply_callback).Run(true);
- return;
- }
- ++attempt;
- DCHECK_LE(attempt, kMaxDeleteAttempts);
- if (attempt == kMaxDeleteAttempts) {
- // Log kMaxDeleteAttempts to indicate failure after exhausting all attempts.
- LogFileDeleteRetryCount(recursive, attempt);
- if (!reply_callback.is_null())
- std::move(reply_callback).Run(false);
- return;
- }
- ThreadPool::PostDelayedTask(FROM_HERE,
- {TaskPriority::BEST_EFFORT, MayBlock()},
- BindOnce(&DeleteFileWithRetry, path, recursive,
- attempt, std::move(reply_callback)),
- kDeleteFileRetryDelay);
- }
- OnceClosure GetDeleteFileCallbackInternal(
- const FilePath& path,
- bool recursive,
- OnceCallback<void(bool)> reply_callback) {
- OnceCallback<void(bool)> bound_callback;
- if (!reply_callback.is_null()) {
- bound_callback = BindPostTask(SequencedTaskRunnerHandle::Get(),
- std::move(reply_callback));
- }
- return BindOnce(&DeleteFileWithRetry, path, recursive, /*attempt=*/0,
- std::move(bound_callback));
- }
- } // namespace
- OnceClosure GetDeleteFileCallback(const FilePath& path,
- OnceCallback<void(bool)> reply_callback) {
- return GetDeleteFileCallbackInternal(path, /*recursive=*/false,
- std::move(reply_callback));
- }
- OnceClosure GetDeletePathRecursivelyCallback(
- const FilePath& path,
- OnceCallback<void(bool)> reply_callback) {
- return GetDeleteFileCallbackInternal(path, /*recursive=*/true,
- std::move(reply_callback));
- }
- FilePath MakeAbsoluteFilePath(const FilePath& input) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- wchar_t file_path[MAX_PATH];
- if (!_wfullpath(file_path, input.value().c_str(), MAX_PATH))
- return FilePath();
- return FilePath(file_path);
- }
- bool DeleteFile(const FilePath& path) {
- return DeleteFileOrSetLastError(path, /*recursive=*/false);
- }
- bool DeletePathRecursively(const FilePath& path) {
- return DeleteFileOrSetLastError(path, /*recursive=*/true);
- }
- bool DeleteFileAfterReboot(const FilePath& path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- if (path.value().length() >= MAX_PATH)
- return false;
- return ::MoveFileEx(path.value().c_str(), nullptr,
- MOVEFILE_DELAY_UNTIL_REBOOT);
- }
- bool ReplaceFile(const FilePath& from_path,
- const FilePath& to_path,
- File::Error* error) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- // Alias paths for investigation of shutdown hangs. crbug.com/1054164
- FilePath::CharType from_path_str[MAX_PATH];
- base::wcslcpy(from_path_str, from_path.value().c_str(),
- std::size(from_path_str));
- base::debug::Alias(from_path_str);
- FilePath::CharType to_path_str[MAX_PATH];
- base::wcslcpy(to_path_str, to_path.value().c_str(), std::size(to_path_str));
- base::debug::Alias(to_path_str);
- // Assume that |to_path| already exists and try the normal replace. This will
- // fail with ERROR_FILE_NOT_FOUND if |to_path| does not exist. When writing to
- // a network share, we may not be able to change the ACLs. Ignore ACL errors
- // then (REPLACEFILE_IGNORE_MERGE_ERRORS).
- if (::ReplaceFile(to_path.value().c_str(), from_path.value().c_str(), NULL,
- REPLACEFILE_IGNORE_MERGE_ERRORS, NULL, NULL)) {
- return true;
- }
- File::Error replace_error = File::OSErrorToFileError(GetLastError());
- // Try a simple move next. It will only succeed when |to_path| doesn't already
- // exist.
- if (::MoveFile(from_path.value().c_str(), to_path.value().c_str()))
- return true;
- // In the case of FILE_ERROR_NOT_FOUND from ReplaceFile, it is likely that
- // |to_path| does not exist. In this case, the more relevant error comes
- // from the call to MoveFile.
- if (error) {
- *error = replace_error == File::FILE_ERROR_NOT_FOUND
- ? File::GetLastFileError()
- : replace_error;
- }
- return false;
- }
- bool CopyDirectory(const FilePath& from_path,
- const FilePath& to_path,
- bool recursive) {
- return DoCopyDirectory(from_path, to_path, recursive, false);
- }
- bool CopyDirectoryExcl(const FilePath& from_path,
- const FilePath& to_path,
- bool recursive) {
- return DoCopyDirectory(from_path, to_path, recursive, true);
- }
- bool PathExists(const FilePath& path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- return (GetFileAttributes(path.value().c_str()) != INVALID_FILE_ATTRIBUTES);
- }
- namespace {
- bool PathHasAccess(const FilePath& path,
- DWORD dir_desired_access,
- DWORD file_desired_access) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- const wchar_t* const path_str = path.value().c_str();
- DWORD fileattr = GetFileAttributes(path_str);
- if (fileattr == INVALID_FILE_ATTRIBUTES)
- return false;
- bool is_directory = fileattr & FILE_ATTRIBUTE_DIRECTORY;
- DWORD desired_access =
- is_directory ? dir_desired_access : file_desired_access;
- DWORD flags_and_attrs =
- is_directory ? FILE_FLAG_BACKUP_SEMANTICS : FILE_ATTRIBUTE_NORMAL;
- win::ScopedHandle file(CreateFile(path_str, desired_access, kFileShareAll,
- nullptr, OPEN_EXISTING, flags_and_attrs,
- nullptr));
- return file.is_valid();
- }
- } // namespace
- bool PathIsReadable(const FilePath& path) {
- return PathHasAccess(path, FILE_LIST_DIRECTORY, GENERIC_READ);
- }
- bool PathIsWritable(const FilePath& path) {
- return PathHasAccess(path, FILE_ADD_FILE, GENERIC_WRITE);
- }
- bool DirectoryExists(const FilePath& path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- DWORD fileattr = GetFileAttributes(path.value().c_str());
- if (fileattr != INVALID_FILE_ATTRIBUTES)
- return (fileattr & FILE_ATTRIBUTE_DIRECTORY) != 0;
- return false;
- }
- bool GetTempDir(FilePath* 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;
- // TODO(evanm): the old behavior of this function was to always strip the
- // trailing slash. We duplicate this here, but it shouldn't be necessary
- // when everyone is using the appropriate FilePath APIs.
- *path = FilePath(temp_path).StripTrailingSeparators();
- return true;
- }
- FilePath GetHomeDir() {
- wchar_t result[MAX_PATH];
- if (SUCCEEDED(SHGetFolderPath(NULL, CSIDL_PROFILE, NULL, SHGFP_TYPE_CURRENT,
- result)) &&
- result[0]) {
- return FilePath(result);
- }
- // Fall back to the temporary directory on failure.
- FilePath temp;
- if (GetTempDir(&temp))
- return temp;
- // Last resort.
- return FilePath(FILE_PATH_LITERAL("C:\\"));
- }
- File CreateAndOpenTemporaryFileInDir(const FilePath& dir, FilePath* temp_file) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- // Open the file with exclusive r/w/d access, and allow the caller to decide
- // to mark it for deletion upon close after the fact.
- constexpr uint32_t kFlags = File::FLAG_CREATE | File::FLAG_READ |
- File::FLAG_WRITE | File::FLAG_WIN_EXCLUSIVE_READ |
- File::FLAG_WIN_EXCLUSIVE_WRITE |
- File::FLAG_CAN_DELETE_ON_CLOSE;
- // Use GUID instead of ::GetTempFileName() to generate unique file names.
- // "Due to the algorithm used to generate file names, GetTempFileName can
- // perform poorly when creating a large number of files with the same prefix.
- // In such cases, it is recommended that you construct unique file names based
- // on GUIDs."
- // https://msdn.microsoft.com/library/windows/desktop/aa364991.aspx
- FilePath temp_name;
- File file;
- // Although it is nearly impossible to get a duplicate name with GUID, we
- // still use a loop here in case it happens.
- for (int i = 0; i < 100; ++i) {
- temp_name = dir.Append(FormatTemporaryFileName(UTF8ToWide(GenerateGUID())));
- file.Initialize(temp_name, kFlags);
- if (file.IsValid())
- break;
- }
- if (!file.IsValid()) {
- DPLOG(WARNING) << "Failed to get temporary file name in " << dir.value();
- return file;
- }
- wchar_t long_temp_name[MAX_PATH + 1];
- const DWORD long_name_len =
- GetLongPathName(temp_name.value().c_str(), long_temp_name, MAX_PATH);
- if (long_name_len != 0 && long_name_len <= MAX_PATH) {
- *temp_file =
- FilePath(FilePath::StringPieceType(long_temp_name, long_name_len));
- } else {
- // GetLongPathName() failed, but we still have a temporary file.
- *temp_file = std::move(temp_name);
- }
- return file;
- }
- bool CreateTemporaryFileInDir(const FilePath& dir, FilePath* temp_file) {
- return CreateAndOpenTemporaryFileInDir(dir, temp_file).IsValid();
- }
- FilePath FormatTemporaryFileName(FilePath::StringPieceType identifier) {
- return FilePath(StrCat({identifier, FILE_PATH_LITERAL(".tmp")}));
- }
- ScopedFILE CreateAndOpenTemporaryStreamInDir(const FilePath& dir,
- FilePath* path) {
- // Open file in binary mode, to avoid problems with fwrite. On Windows
- // it replaces \n's with \r\n's, which may surprise you.
- // Reference: http://msdn.microsoft.com/en-us/library/h9t88zwz(VS.71).aspx
- return ScopedFILE(
- FileToFILE(CreateAndOpenTemporaryFileInDir(dir, path), "wb+"));
- }
- bool CreateTemporaryDirInDir(const FilePath& base_dir,
- const FilePath::StringType& prefix,
- FilePath* new_dir) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- FilePath path_to_create;
- for (int count = 0; count < 50; ++count) {
- // Try create a new temporary directory with random generated name. If
- // the one exists, keep trying another path name until we reach some limit.
- std::wstring new_dir_name;
- new_dir_name.assign(prefix);
- new_dir_name.append(AsWString(NumberToString16(GetCurrentProcId())));
- new_dir_name.push_back('_');
- new_dir_name.append(AsWString(
- NumberToString16(RandInt(0, std::numeric_limits<int32_t>::max()))));
- path_to_create = base_dir.Append(new_dir_name);
- if (::CreateDirectory(path_to_create.value().c_str(), NULL)) {
- *new_dir = path_to_create;
- return true;
- }
- }
- return false;
- }
- bool CreateNewTempDirectory(const FilePath::StringType& prefix,
- FilePath* new_temp_path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- FilePath system_temp_dir;
- if (!GetTempDir(&system_temp_dir))
- return false;
- return CreateTemporaryDirInDir(system_temp_dir, prefix, new_temp_path);
- }
- bool CreateDirectoryAndGetError(const FilePath& full_path,
- File::Error* error) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- // If the path exists, we've succeeded if it's a directory, failed otherwise.
- const wchar_t* const full_path_str = full_path.value().c_str();
- const DWORD fileattr = ::GetFileAttributes(full_path_str);
- if (fileattr != INVALID_FILE_ATTRIBUTES) {
- if ((fileattr & FILE_ATTRIBUTE_DIRECTORY) != 0) {
- return true;
- }
- DLOG(WARNING) << "CreateDirectory(" << full_path_str << "), "
- << "conflicts with existing file.";
- if (error)
- *error = File::FILE_ERROR_NOT_A_DIRECTORY;
- ::SetLastError(ERROR_FILE_EXISTS);
- return false;
- }
- // Invariant: Path does not exist as file or directory.
- // Attempt to create the parent recursively. This will immediately return
- // true if it already exists, otherwise will create all required parent
- // directories starting with the highest-level missing parent.
- FilePath parent_path(full_path.DirName());
- if (parent_path.value() == full_path.value()) {
- if (error)
- *error = File::FILE_ERROR_NOT_FOUND;
- ::SetLastError(ERROR_FILE_NOT_FOUND);
- return false;
- }
- if (!CreateDirectoryAndGetError(parent_path, error)) {
- DLOG(WARNING) << "Failed to create one of the parent directories.";
- DCHECK(!error || *error != File::FILE_OK);
- return false;
- }
- if (::CreateDirectory(full_path_str, NULL))
- return true;
- const DWORD error_code = ::GetLastError();
- if (error_code == ERROR_ALREADY_EXISTS && DirectoryExists(full_path)) {
- // This error code ERROR_ALREADY_EXISTS doesn't indicate whether we were
- // racing with someone creating the same directory, or a file with the same
- // path. If DirectoryExists() returns true, we lost the race to create the
- // same directory.
- return true;
- }
- if (error)
- *error = File::OSErrorToFileError(error_code);
- ::SetLastError(error_code);
- DPLOG(WARNING) << "Failed to create directory " << full_path_str;
- return false;
- }
- bool NormalizeFilePath(const FilePath& path, FilePath* real_path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- File file(path,
- File::FLAG_OPEN | File::FLAG_READ | File::FLAG_WIN_SHARE_DELETE);
- if (!file.IsValid())
- return false;
- // The expansion of |path| into a full path may make it longer.
- constexpr int kMaxPathLength = MAX_PATH + 10;
- wchar_t native_file_path[kMaxPathLength];
- // kMaxPathLength includes space for trailing '\0' so we subtract 1.
- // Returned length, used_wchars, does not include trailing '\0'.
- // Failure is indicated by returning 0 or >= kMaxPathLength.
- DWORD used_wchars = ::GetFinalPathNameByHandle(
- file.GetPlatformFile(), native_file_path, kMaxPathLength - 1,
- FILE_NAME_NORMALIZED | VOLUME_NAME_NT);
- if (used_wchars >= kMaxPathLength || used_wchars == 0)
- return false;
- // GetFinalPathNameByHandle() returns the \\?\ syntax for file names and
- // existing code expects we return a path starting 'X:\' so we call
- // DevicePathToDriveLetterPath rather than using VOLUME_NAME_DOS above.
- return DevicePathToDriveLetterPath(
- FilePath(FilePath::StringPieceType(native_file_path, used_wchars)),
- real_path);
- }
- bool DevicePathToDriveLetterPath(const FilePath& nt_device_path,
- FilePath* out_drive_letter_path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- // Get the mapping of drive letters to device paths.
- const int kDriveMappingSize = 1024;
- wchar_t drive_mapping[kDriveMappingSize] = {'\0'};
- if (!::GetLogicalDriveStrings(kDriveMappingSize - 1, drive_mapping)) {
- DLOG(ERROR) << "Failed to get drive mapping.";
- return false;
- }
- // The drive mapping is a sequence of null terminated strings.
- // The last string is empty.
- wchar_t* drive_map_ptr = drive_mapping;
- wchar_t device_path_as_string[MAX_PATH];
- wchar_t drive[] = FILE_PATH_LITERAL(" :");
- // For each string in the drive mapping, get the junction that links
- // to it. If that junction is a prefix of |device_path|, then we
- // know that |drive| is the real path prefix.
- while (*drive_map_ptr) {
- drive[0] = drive_map_ptr[0]; // Copy the drive letter.
- if (QueryDosDevice(drive, device_path_as_string, MAX_PATH)) {
- FilePath device_path(device_path_as_string);
- if (device_path == nt_device_path ||
- device_path.IsParent(nt_device_path)) {
- *out_drive_letter_path =
- FilePath(drive + nt_device_path.value().substr(
- wcslen(device_path_as_string)));
- return true;
- }
- }
- // Move to the next drive letter string, which starts one
- // increment after the '\0' that terminates the current string.
- while (*drive_map_ptr++) {}
- }
- // No drive matched. The path does not start with a device junction
- // that is mounted as a drive letter. This means there is no drive
- // letter path to the volume that holds |device_path|, so fail.
- return false;
- }
- FilePath MakeLongFilePath(const FilePath& input) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- DWORD path_long_len = ::GetLongPathName(input.value().c_str(), nullptr, 0);
- if (path_long_len == 0UL)
- return FilePath();
- std::wstring path_long_str;
- path_long_len = ::GetLongPathName(input.value().c_str(),
- WriteInto(&path_long_str, path_long_len),
- path_long_len);
- if (path_long_len == 0UL)
- return FilePath();
- return FilePath(path_long_str);
- }
- bool CreateWinHardLink(const FilePath& to_file, const FilePath& from_file) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- return ::CreateHardLink(to_file.value().c_str(), from_file.value().c_str(),
- nullptr);
- }
- // TODO(rkc): Work out if we want to handle NTFS junctions here or not, handle
- // them if we do decide to.
- bool IsLink(const FilePath& file_path) {
- return false;
- }
- bool GetFileInfo(const FilePath& file_path, File::Info* results) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- WIN32_FILE_ATTRIBUTE_DATA attr;
- if (!GetFileAttributesEx(file_path.value().c_str(), GetFileExInfoStandard,
- &attr)) {
- return false;
- }
- ULARGE_INTEGER size;
- size.HighPart = attr.nFileSizeHigh;
- size.LowPart = attr.nFileSizeLow;
- // TODO(crbug.com/1333521): Change Info::size to uint64_t and eliminate this
- // cast.
- results->size = checked_cast<int64_t>(size.QuadPart);
- results->is_directory =
- (attr.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
- results->last_modified = Time::FromFileTime(attr.ftLastWriteTime);
- results->last_accessed = Time::FromFileTime(attr.ftLastAccessTime);
- results->creation_time = Time::FromFileTime(attr.ftCreationTime);
- return true;
- }
- FILE* OpenFile(const FilePath& filename, const char* mode) {
- // 'N' is unconditionally added below, so be sure there is not one already
- // present before a comma in |mode|.
- DCHECK(
- strchr(mode, 'N') == nullptr ||
- (strchr(mode, ',') != nullptr && strchr(mode, 'N') > strchr(mode, ',')));
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- std::wstring w_mode = UTF8ToWide(mode);
- AppendModeCharacter(L'N', &w_mode);
- return _wfsopen(filename.value().c_str(), w_mode.c_str(), _SH_DENYNO);
- }
- FILE* FileToFILE(File file, const char* mode) {
- DCHECK(!file.async());
- if (!file.IsValid())
- return NULL;
- int fd =
- _open_osfhandle(reinterpret_cast<intptr_t>(file.GetPlatformFile()), 0);
- if (fd < 0)
- return NULL;
- file.TakePlatformFile();
- FILE* stream = _fdopen(fd, mode);
- if (!stream)
- _close(fd);
- return stream;
- }
- File FILEToFile(FILE* file_stream) {
- if (!file_stream)
- return File();
- int fd = _fileno(file_stream);
- DCHECK_GE(fd, 0);
- intptr_t file_handle = _get_osfhandle(fd);
- DCHECK_NE(file_handle, reinterpret_cast<intptr_t>(INVALID_HANDLE_VALUE));
- HANDLE other_handle = nullptr;
- if (!::DuplicateHandle(
- /*hSourceProcessHandle=*/GetCurrentProcess(),
- reinterpret_cast<HANDLE>(file_handle),
- /*hTargetProcessHandle=*/GetCurrentProcess(), &other_handle,
- /*dwDesiredAccess=*/0,
- /*bInheritHandle=*/FALSE,
- /*dwOptions=*/DUPLICATE_SAME_ACCESS)) {
- return File(File::GetLastFileError());
- }
- return File(ScopedPlatformFile(other_handle));
- }
- int ReadFile(const FilePath& filename, char* data, int max_size) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- win::ScopedHandle file(CreateFile(filename.value().c_str(), GENERIC_READ,
- FILE_SHARE_READ | FILE_SHARE_WRITE, NULL,
- OPEN_EXISTING, FILE_FLAG_SEQUENTIAL_SCAN,
- NULL));
- if (!file.is_valid() || max_size < 0)
- return -1;
- DWORD read;
- if (::ReadFile(file.get(), data, static_cast<DWORD>(max_size), &read, NULL)) {
- // TODO(crbug.com/1333521): Change to return some type with a uint64_t size
- // and eliminate this cast.
- return checked_cast<int>(read);
- }
- return -1;
- }
- int WriteFile(const FilePath& filename, const char* data, int size) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- win::ScopedHandle file(CreateFile(filename.value().c_str(), GENERIC_WRITE, 0,
- NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL,
- NULL));
- if (!file.is_valid() || size < 0) {
- DPLOG(WARNING) << "WriteFile failed for path " << filename.value();
- return -1;
- }
- DWORD written;
- BOOL result =
- ::WriteFile(file.get(), data, static_cast<DWORD>(size), &written, NULL);
- if (result && static_cast<int>(written) == size)
- return static_cast<int>(written);
- if (!result) {
- // WriteFile failed.
- DPLOG(WARNING) << "writing file " << filename.value() << " failed";
- } else {
- // Didn't write all the bytes.
- DLOG(WARNING) << "wrote" << written << " bytes to " << filename.value()
- << " expected " << size;
- }
- return -1;
- }
- bool AppendToFile(const FilePath& filename, span<const uint8_t> data) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- win::ScopedHandle file(CreateFile(filename.value().c_str(), FILE_APPEND_DATA,
- 0, nullptr, OPEN_EXISTING, 0, nullptr));
- if (!file.is_valid()) {
- VPLOG(1) << "CreateFile failed for path " << filename.value();
- return false;
- }
- DWORD written;
- DWORD size = checked_cast<DWORD>(data.size());
- BOOL result = ::WriteFile(file.get(), data.data(), size, &written, nullptr);
- if (result && written == size)
- return true;
- if (!result) {
- // WriteFile failed.
- VPLOG(1) << "Writing file " << filename.value() << " failed";
- } else {
- // Didn't write all the bytes.
- VPLOG(1) << "Only wrote " << written << " out of " << size << " byte(s) to "
- << filename.value();
- }
- return false;
- }
- bool AppendToFile(const FilePath& filename, StringPiece data) {
- return AppendToFile(filename, as_bytes(make_span(data)));
- }
- bool GetCurrentDirectory(FilePath* dir) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- wchar_t system_buffer[MAX_PATH];
- system_buffer[0] = 0;
- DWORD len = ::GetCurrentDirectory(MAX_PATH, system_buffer);
- if (len == 0 || len > MAX_PATH)
- return false;
- // TODO(evanm): the old behavior of this function was to always strip the
- // trailing slash. We duplicate this here, but it shouldn't be necessary
- // when everyone is using the appropriate FilePath APIs.
- *dir = FilePath(FilePath::StringPieceType(system_buffer))
- .StripTrailingSeparators();
- return true;
- }
- bool SetCurrentDirectory(const FilePath& directory) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- return ::SetCurrentDirectory(directory.value().c_str()) != 0;
- }
- int GetMaximumPathComponentLength(const FilePath& path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- wchar_t volume_path[MAX_PATH];
- if (!GetVolumePathNameW(path.NormalizePathSeparators().value().c_str(),
- volume_path, std::size(volume_path))) {
- return -1;
- }
- DWORD max_length = 0;
- if (!GetVolumeInformationW(volume_path, NULL, 0, NULL, &max_length, NULL,
- NULL, 0)) {
- return -1;
- }
- // Length of |path| with path separator appended.
- size_t prefix = path.StripTrailingSeparators().value().size() + 1;
- // The whole path string must be shorter than MAX_PATH. That is, it must be
- // prefix + component_length < MAX_PATH (or equivalently, <= MAX_PATH - 1).
- int whole_path_limit = std::max(0, MAX_PATH - 1 - static_cast<int>(prefix));
- return std::min(whole_path_limit, static_cast<int>(max_length));
- }
- bool CopyFile(const FilePath& from_path, const FilePath& to_path) {
- return DoCopyFile(from_path, to_path, false);
- }
- bool SetNonBlocking(int fd) {
- unsigned long nonblocking = 1;
- if (ioctlsocket(static_cast<SOCKET>(fd), static_cast<long>(FIONBIO),
- &nonblocking) == 0)
- return true;
- return false;
- }
- namespace {
- // ::PrefetchVirtualMemory() is only available on Windows 8 and above. Chrome
- // supports Windows 7, so we need to check for the function's presence
- // dynamically.
- using PrefetchVirtualMemoryPtr = decltype(&::PrefetchVirtualMemory);
- // Returns null if ::PrefetchVirtualMemory() is not available.
- PrefetchVirtualMemoryPtr GetPrefetchVirtualMemoryPtr() {
- HMODULE kernel32_dll = ::GetModuleHandleA("kernel32.dll");
- return reinterpret_cast<PrefetchVirtualMemoryPtr>(
- GetProcAddress(kernel32_dll, "PrefetchVirtualMemory"));
- }
- } // namespace
- bool PreReadFile(const FilePath& file_path,
- bool is_executable,
- int64_t max_bytes) {
- DCHECK_GE(max_bytes, 0);
- // On Win8 and higher use ::PrefetchVirtualMemory(). This is better than a
- // simple data file read, more from a RAM perspective than CPU. This is
- // because reading the file as data results in double mapping to
- // Image/executable pages for all pages of code executed.
- static PrefetchVirtualMemoryPtr prefetch_virtual_memory =
- GetPrefetchVirtualMemoryPtr();
- if (prefetch_virtual_memory == nullptr)
- return internal::PreReadFileSlow(file_path, max_bytes);
- if (max_bytes == 0) {
- // PrefetchVirtualMemory() fails when asked to read zero bytes.
- // base::MemoryMappedFile::Initialize() fails on an empty file.
- return true;
- }
- // PrefetchVirtualMemory() fails if the file is opened with write access.
- MemoryMappedFile::Access access = is_executable
- ? MemoryMappedFile::READ_CODE_IMAGE
- : MemoryMappedFile::READ_ONLY;
- MemoryMappedFile mapped_file;
- if (!mapped_file.Initialize(file_path, access))
- return internal::PreReadFileSlow(file_path, max_bytes);
- const ::SIZE_T length =
- std::min(base::saturated_cast<::SIZE_T>(max_bytes),
- base::saturated_cast<::SIZE_T>(mapped_file.length()));
- ::_WIN32_MEMORY_RANGE_ENTRY address_range = {mapped_file.data(), length};
- if (!prefetch_virtual_memory(::GetCurrentProcess(),
- /*NumberOfEntries=*/1, &address_range,
- /*Flags=*/0)) {
- return internal::PreReadFileSlow(file_path, max_bytes);
- }
- return true;
- }
- // -----------------------------------------------------------------------------
- namespace internal {
- bool MoveUnsafe(const FilePath& from_path, const FilePath& to_path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- // NOTE: I suspect we could support longer paths, but that would involve
- // analyzing all our usage of files.
- if (from_path.value().length() >= MAX_PATH ||
- to_path.value().length() >= MAX_PATH) {
- return false;
- }
- if (MoveFileEx(from_path.value().c_str(), to_path.value().c_str(),
- MOVEFILE_COPY_ALLOWED | MOVEFILE_REPLACE_EXISTING) != 0)
- return true;
- // Keep the last error value from MoveFileEx around in case the below
- // fails.
- bool ret = false;
- DWORD last_error = ::GetLastError();
- if (DirectoryExists(from_path)) {
- // MoveFileEx fails if moving directory across volumes. We will simulate
- // the move by using Copy and Delete. Ideally we could check whether
- // from_path and to_path are indeed in different volumes.
- ret = internal::CopyAndDeleteDirectory(from_path, to_path);
- }
- if (!ret) {
- // Leave a clue about what went wrong so that it can be (at least) picked
- // up by a PLOG entry.
- ::SetLastError(last_error);
- }
- return ret;
- }
- bool CopyAndDeleteDirectory(const FilePath& from_path,
- const FilePath& to_path) {
- ScopedBlockingCall scoped_blocking_call(FROM_HERE, BlockingType::MAY_BLOCK);
- if (CopyDirectory(from_path, to_path, true)) {
- if (DeletePathRecursively(from_path))
- return true;
- // Like Move, this function is not transactional, so we just
- // leave the copied bits behind if deleting from_path fails.
- // If to_path exists previously then we have already overwritten
- // it by now, we don't get better off by deleting the new bits.
- }
- return false;
- }
- } // namespace internal
- } // namespace base
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