Support: Have directory_iterator::status() return FindFirstFileEx/FindNextFile results on Windows.
This allows clients to avoid an unnecessary fs::status() call on each
directory entry. Because the information returned by FindFirstFileEx
is a subset of the information returned by a regular status() call,
I needed to extract a base class from file_status that contains only
that information.
On my machine, this reduces the time required to enumerate a ThinLTO
cache directory containing 520k files from almost 4 minutes to less
than 2 seconds.
Differential Revision: https://reviews.llvm.org/D38716
llvm-svn: 315378
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index a81cd58..1ab354b 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -168,14 +168,14 @@
return SpaceInfo;
}
-TimePoint<> file_status::getLastAccessedTime() const {
+TimePoint<> basic_file_status::getLastAccessedTime() const {
FILETIME Time;
Time.dwLowDateTime = LastAccessedTimeLow;
Time.dwHighDateTime = LastAccessedTimeHigh;
return toTimePoint(Time);
}
-TimePoint<> file_status::getLastModificationTime() const {
+TimePoint<> basic_file_status::getLastModificationTime() const {
FILETIME Time;
Time.dwLowDateTime = LastWriteTimeLow;
Time.dwHighDateTime = LastWriteTimeHigh;
@@ -569,6 +569,15 @@
return false;
}
+static file_type file_type_from_attrs(DWORD Attrs) {
+ return (Attrs & FILE_ATTRIBUTE_DIRECTORY) ? file_type::directory_file
+ : file_type::regular_file;
+}
+
+static perms perms_from_attrs(DWORD Attrs) {
+ return (Attrs & FILE_ATTRIBUTE_READONLY) ? (all_read | all_exe) : all_all;
+}
+
static std::error_code getStatus(HANDLE FileHandle, file_status &Result) {
if (FileHandle == INVALID_HANDLE_VALUE)
goto handle_status_error;
@@ -597,22 +606,14 @@
if (!::GetFileInformationByHandle(FileHandle, &Info))
goto handle_status_error;
- {
- file_type Type = (Info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
- ? file_type::directory_file
- : file_type::regular_file;
- perms Permissions = (Info.dwFileAttributes & FILE_ATTRIBUTE_READONLY)
- ? (all_read | all_exe)
- : all_all;
- Result = file_status(
- Type, Permissions, Info.nNumberOfLinks,
- Info.ftLastAccessTime.dwHighDateTime,
- Info.ftLastAccessTime.dwLowDateTime,
- Info.ftLastWriteTime.dwHighDateTime, Info.ftLastWriteTime.dwLowDateTime,
- Info.dwVolumeSerialNumber, Info.nFileSizeHigh, Info.nFileSizeLow,
- Info.nFileIndexHigh, Info.nFileIndexLow);
- return std::error_code();
- }
+ Result = file_status(
+ file_type_from_attrs(Info.dwFileAttributes),
+ perms_from_attrs(Info.dwFileAttributes), Info.nNumberOfLinks,
+ Info.ftLastAccessTime.dwHighDateTime, Info.ftLastAccessTime.dwLowDateTime,
+ Info.ftLastWriteTime.dwHighDateTime, Info.ftLastWriteTime.dwLowDateTime,
+ Info.dwVolumeSerialNumber, Info.nFileSizeHigh, Info.nFileSizeLow,
+ Info.nFileIndexHigh, Info.nFileIndexLow);
+ return std::error_code();
handle_status_error:
DWORD LastError = ::GetLastError();
@@ -798,6 +799,16 @@
return SysInfo.dwAllocationGranularity;
}
+static basic_file_status status_from_find_data(WIN32_FIND_DATA *FindData) {
+ return basic_file_status(file_type_from_attrs(FindData->dwFileAttributes),
+ perms_from_attrs(FindData->dwFileAttributes),
+ FindData->ftLastAccessTime.dwHighDateTime,
+ FindData->ftLastAccessTime.dwLowDateTime,
+ FindData->ftLastWriteTime.dwHighDateTime,
+ FindData->ftLastWriteTime.dwLowDateTime,
+ FindData->nFileSizeHigh, FindData->nFileSizeLow);
+}
+
std::error_code detail::directory_iterator_construct(detail::DirIterState &it,
StringRef path,
bool follow_symlinks) {
@@ -818,7 +829,9 @@
// Get the first directory entry.
WIN32_FIND_DATAW FirstFind;
- ScopedFindHandle FindHandle(::FindFirstFileW(c_str(path_utf16), &FirstFind));
+ ScopedFindHandle FindHandle(::FindFirstFileExW(
+ c_str(path_utf16), FindExInfoBasic, &FirstFind, FindExSearchNameMatch,
+ NULL, FIND_FIRST_EX_LARGE_FETCH));
if (!FindHandle)
return mapWindowsError(::GetLastError());
@@ -845,7 +858,8 @@
it.IterationHandle = intptr_t(FindHandle.take());
SmallString<128> directory_entry_path(path);
path::append(directory_entry_path, directory_entry_name_utf8);
- it.CurrentEntry = directory_entry(directory_entry_path, follow_symlinks);
+ it.CurrentEntry = directory_entry(directory_entry_path, follow_symlinks,
+ status_from_find_data(&FirstFind));
return std::error_code();
}
@@ -881,10 +895,15 @@
directory_entry_path_utf8))
return ec;
- it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8));
+ it.CurrentEntry.replace_filename(Twine(directory_entry_path_utf8),
+ status_from_find_data(&FindData));
return std::error_code();
}
+ErrorOr<basic_file_status> directory_entry::status() const {
+ return Status;
+}
+
static std::error_code realPathFromHandle(HANDLE H,
SmallVectorImpl<char> &RealPath) {
RealPath.clear();